Golf club head with low hosel bore

Abstract

Iron-type golf club heads have a shortened hosel and lengthened hosel bore. The iron-type golf club head allows for a range of loft and lie adjustability post-manufacture with maintained or reduced visible surface deformation and durability loss, and also creates discretionary mass that can be placed strategically for performance benefits. Additionally, an insert having weight members is coupled to a rear of the club head to facilitate swing weighting.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation in part of U.S. patent application Ser. No. 18 / 476,266 filed on Sep. 27, 2023, which claims the benefit of U.S. Provisional Application No. 63 / 377,324, filed Sep. 27, 2022. This application also claims the benefit of U.S. Provisional Patent Application No. 63 / 669,183, filed on Jul. 9, 2024, U.S. Provisional Patent Application No. 63 / 783,392, filed on Apr. 4, 2025, and U.S. Provisional Patent Application No. 63 / 837,742, filed on Jul. 2, 2025. The contents of all of the above described disclosures are fully incorporated by reference herein in their entirety.FIELD OF THE INVENTION

[0002] The present disclosure relates to a golf club, and more specifically to a hosel and weighting designs for golf club heads.BACKGROUND

[0003] Golfers will often customize a club or set of clubs to best suit their personal swing style, height, or combination of physical factors. Clubs are often customized by adjusting loft and lie angle to ensure the player's club face is lined up correctly at address. Typically, a golf club head is ordered with the specifications of a player's custom adjustments ahead of time, and that club is then manufactured according to those specifications. This can cause long lead times and can limit the ability to later adjust the club head specifications. It is advantageous, therefore, to facilitate bending of the face angle during assembly processes, post-manufacture, or post-fabrication. Such bending, however, increases the risk of deformation at the bend site, creating unsightly marks or negatively impacting durability of certain finishes such as chrome.

[0004] During manufacture, the face of a golf club is typically oriented relative to the hosel to obtain initial loft and lie angles. The golf club may be further manipulated, for example, by bending, post-fabrication, to obtain final loft and lie angles. As the hosel is bent further, the club will develop cosmetic flaws, such as stress marks, and / or will structurally fail. For example, conventional club heads are typically limited to approximately ±2 degrees of post-fabrication bending before developing stress marks or structurally failing. Thus, it would be advantageous to provide a golf club head that can withstand post-fabrication bending without substantial stress marks or failure.BRIEF DESCRIPTION OF THE DRAWINGS

[0005] The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.

[0006] FIG. 1A illustrates a front perspective view of an exemplary embodiment of a golf club head according to the present disclosure.

[0007] FIG. 1B illustrates 1 a front view of the exemplary golf club head of FIG. 1A.

[0008] FIG. 2 illustrates a top view of the exemplary golf club head of FIG. 1A.

[0009] FIG. 3 illustrates a rear perspective view of the exemplary golf club head of FIG. 1A.

[0010] FIG. 4 illustrates a toe side view of the exemplary golf club of FIG. 1A.

[0011] FIG. 5A illustrates a cross-sectional view of the exemplary golf club head of FIG. 1A, along the line 5A-5A of FIG. 2.

[0012] FIG. 5B illustrates stress concentration of a first section of the exemplary golf club of FIG. 1 during a first set of conditions.

[0013] FIG. 5C illustrates stress concentration of a second section of the exemplary golf club of FIG. 1 during a first set of conditions.

[0014] FIG. 5D illustrates stress concentration of a third section of the exemplary golf club of FIG. 1 during a first set of conditions.

[0015] FIG. 6A illustrates a cross-sectional view of a conventional golf club head, along the same line as that shown in FIG. 5A.

[0016] FIG. 6B illustrates stress concentration of a first section of the golf club of FIG. 6A during the first set of conditions.

[0017] FIG. 6C illustrates stress concentration of a second section of the golf club of FIG. 6A during the first set of conditions.

[0018] FIG. 6D illustrates stress concentration of a third section of the golf club of FIG. 6A during the first set of conditions.

[0019] FIG. 7 illustrates a front cross-sectional view of a standard golf club head, along the line 5A-5A of FIG. 2.

[0020] FIG. 8 illustrates a front, cross-sectional view of the exemplary golf club head of FIG. 1A, along the line 5A-5A of FIG. 2.

[0021] FIG. 9 illustrates a cross-sectional view of an example of an embodiment of a golf club head, along the line 5A-5A of FIG. 2.

[0022] FIG. 10 illustrates a cross-sectional view of the exemplary golf club head of FIG. 1A, along the line 10-10 of FIG. 1B.

[0023] FIG. 11 illustrates a cross-sectional view of the exemplary golf club head of FIG. 1A, along the line 11-11 of FIG. 1B.

[0024] FIG. 12 illustrates a cross-sectional view of the exemplary golf club head of FIG. 1A, along the line 12-12 of FIG. 1B.

[0025] FIG. 13 illustrates a perspective view with low opacity of a conventional golf club head, where the opacity has been lowered to display internal features.

[0026] FIG. 14 illustrates a perspective view with low opacity of an exemplary embodiment of a golf club head according to the present disclosure.

[0027] FIG. 15 illustrates a perspective view with low opacity of an exemplary embodiment of a golf club head according to the present disclosure.

[0028] FIG. 16 illustrates a top-down view of one embodiment of a golf club head having a weighted insert of the present invention.

[0029] FIG. 17 illustrates a bottom view of the golf club head of FIG. 16.

[0030] FIG. 18 illustrates a toe-side view of the golf club head of FIG. 16.

[0031] FIG. 19 illustrates a heel-side view of the golf club head of FIG. 16.

[0032] FIG. 20 illustrates a rear view of the golf club head of FIG. 16.

[0033] FIG. 21 illustrates a front view of the golf club head of FIG. 16.

[0034] FIG. 22 illustrates a perspective view of the golf club head of FIG. 16.

[0035] FIG. 23 illustrates a cross-sectional toe-side view of the golf club head of FIG. 16.

[0036] FIG. 24 illustrates a cross-sectional front-side view of the golf club of FIG. 16.

[0037] FIG. 25 illustrates a cross-sectional front-side view of traditional golf club head.

[0038] FIG. 26 illustrates another front view of the golf club head of FIG. 16.

[0039] FIG. 27 illustrates another toe-side view of the golf club head of FIG. 16.

[0040] FIG. 28 illustrates a top-down view of another embodiment of a golf club head having a weighted insert of the present invention.

[0041] FIG. 29 illustrates a bottom view of the golf club head of FIG. 28.

[0042] FIG. 30 illustrates a toe-side view of the golf club head of FIG. 28.

[0043] FIG. 31 illustrates a heel-side view of the golf club head of FIG. 28.

[0044] FIG. 32 illustrates a rear view of the golf club head of FIG. 28.

[0045] FIG. 33 illustrates a front view of the golf club head of FIG. 28.

[0046] FIG. 34 illustrates a perspective view of the golf club head of FIG. 28.

[0047] FIG. 35 illustrates a cross-sectional toe-side view of the golf club head of FIG. 28.

[0048] FIG. 36A illustrates an alternative rear view of the golf club head of FIG. 28.

[0049] FIG. 36B illustrates a detailed view of Section AA of FIG. 36A.

[0050] FIG. 37 illustrates a rear view of the golf club head of FIG. 28 with the insert and first weight member removed.

[0051] FIG. 38 illustrates a toe-side view of one embodiment of a weighted insert of the present invention.

[0052] FIG. 39 illustrates a heel-side view of the weighted insert of FIG. 38.

[0053] FIG. 40 illustrates a rear perspective exploded view of the insert of FIG. 38.

[0054] FIG. 41 illustrates a toe-side cross-sectional view of the weighted insert of FIG. 38.

[0055] FIG. 42 illustrates a perspective view of the weighted insert of FIG. 38.

[0056] FIG. 43 illustrates another perspective view of the weighted insert of FIG. 38.

[0057] FIG. 44 illustrates a rear view of the weighted insert of FIG. 38.

[0058] FIG. 45 illustrates a front view of the weighted insert of FIG. 38.

[0059] FIG. 46 illustrates a set of exemplary graphs comparing frequency and hosel length.

[0060] FIG. 47 illustrates a rear view of a golf club head with a weighted insert and shortened hosel bore of the present invention.

[0061] FIG. 48 illustrates a rear perspective view of the golf club head of FIG. 47, without the weighted insert.

[0062] FIG. 49 illustrates an elevation view of the golf club head with a weighted insert of FIG. 47 in cross-section.

[0063] FIG. 50 illustrates a rear perspective view of a golf club head that can receive a weighted insert of the present invention.

[0064] FIG. 51 illustrates a rear perspective view of a golf club head and a weighted insert of the present invention in cross-section.DEFINITIONS

[0065] For simplicity and clarity of illustration, the drawing figures illustrate the general manner of construction, and descriptions and details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the invention. Additionally, elements in the drawing figures are not necessarily drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of embodiments of the present invention. The same reference numerals in different figures denote the same elements.

[0066] The terms “first,”“second,”“third,”“fourth,”“fifth,” and the like in the description and in the claims, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms “include,” and “have,” and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, device, or apparatus that comprises a list of elements is not necessarily limited to those elements, but may include other elements not expressly listed or inherent to such process, method, system, article, device, or apparatus.

[0067] The terms “left,”“right,”“front,”“back,”“top,”“bottom,”“over,”“under,” as used herein, are for descriptive purposes and not necessarily for describing permanent relative positions. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the apparatus, methods, and / or articles of manufacture described herein are, for example, capable of operation in other orientations than those illustrated or otherwise described herein.

[0068] The terms “couple,”“coupled,”“couples,”“coupling,” as used herein refers to connecting two or more elements, mechanically or otherwise. Coupling (whether mechanical or otherwise) may be for any length of time, e.g., permanent or semi-permanent or only for an instant.

[0069] The term “strike face,” or “strike surface,” as used herein, refers to a club head front surface that is configured to strike a golf ball. The term strike face can be used interchangeably with the term “face.”

[0070] The term “hosel,” as used herein, refers to a heel-side member of the club head configured to connect the club body with the club shaft.

[0071] The term “geometric centerpoint,” or “face center” of the strike face, as used herein, can refer to a geometric centerpoint of the strike face perimeter 105, and at a midpoint of the face height of the strike face. In the same or other examples, the geometric centerpoint also can be centered with respect to an engineered impact zone, which can be defined by a region of grooves on the strike face. As another approach, the geometric centerpoint of the strike face can be located in accordance with the definition of a golf governing body such as the United States Golf Association (USGA).

[0072] The term “ground plane,” as used herein, can refer to a reference plane associated with the surface on which a golf ball is placed. The ground plane can be a horizontal plane tangent to the sole at an address position. The ground plane 160 is illustrated throughout the drawings including FIGS. 1B and 4.

[0073] The term “lie angle,” as used herein, can refer to an angle between a hosel axis, extending through the hosel, and the ground plane. The lie angle is measured from a front view.

[0074] The term “loft,” or “loft angle,” as used herein, can refer to an angle measured between the loft plane and the XY plane (defined below). The loft plane 1022 is illustrated in FIGS. 4 and 27.

[0075] An “XYZ” coordinate system of the golf club head, as used herein, is based upon the geometric center of the strike face. The golf club head dimensions as described herein can be measured based on a coordinate system as defined below. The geometric center of the strike face defines a coordinate system having an origin located at the geometric center of the strike face. The coordinate system defines an X axis, a Y axis, and a Z axis. The X axis extends through the geometric center of the strike face in a direction from the heel to the toe of the fairway-type club head. The Y axis extends through the geometric center of the strike face in a direction from the top rail to the sole of golf club head. The Y axis is perpendicular to the X axis. The Z axis extends through the geometric center of the strike face in a direction from the front end to the rear end of the golf club head. The Z axis is perpendicular to both the X axis and the Y axis.

[0076] The term or phrase “center of gravity position” or “CG location” as used herein refers to the location of the club head center of gravity (CG) with respect to the XYZ coordinate system, wherein the CG position is characterized by locations along the X-axis, the Y-axis, and the Z-axis. The term “CGx” can refer to the CG location along the X-axis, measured from the origin point. The term “CGy” can refer to the CG location along the Y-axis, measured from the origin point. The term “CGz” can refer to the CG location along the Z-axis, measured from the origin point.

[0077] The term or phrase “moment of inertia” (hereafter “MOI”) as used herein is a value derived using the center of gravity (CG) location. The MOI can be calculated by assuming the club head includes the body and the hosel structure. The term “MOIxx” or “Ixx” can refer to the MOI measured about the X′-axis. The term “MOIyy” or “Iyy” can refer to the MOI measured about the Y′-axis. The term “MOIzz” or “Izz” can refer to the MOI measured about the Z′-axis. The MOI values MOIxx, MOIyy, and MOIzz determine how forgiving the club head is for off-center impacts with a golf ball.

[0078] Other features and aspects will become apparent by consideration of the following detailed description and accompanying drawings. Before any embodiments of the disclosure are explained in detail, it should be understood that the disclosure is not limited in its application to the details or construction and the arrangement of components as set forth in the following description or as illustrated in the drawings. The disclosure is capable of supporting other embodiments and of being practiced or of being carried out in various ways. It should be understood that the description of specific embodiments is not intended to limit the disclosure from covering all modifications, equivalents and alternatives falling within the spirit and scope of the disclosure. It is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.

[0079] For ease of discussion and understanding, and for purposes of description only, the following detailed description illustrates a club head 100 as an (or an iron-type club head). It should be appreciated that the iron is provided for purposes of illustration, and one or more of the attributes disclosed herein are not limited to an iron. The attributes can be used on any desired golf club, including an iron, wedge, putter, or other golf club where a resting face angle, hosel tilt, center of gravity (CG), or other attribute is desired to provide an improved performance and aesthetic for a player. For example, the club head 100 can include, but is not limited to, a one-iron, a two-iron, a three-iron, a four-iron, a five-iron, a six-iron, a seven-iron, an eight-iron, a nine-iron, a pitching wedge, a gap wedge, a utility wedge, a sand wedge, a lob wedge, and / or a putter. In addition, the club head 100 can have a loft that can range from approximately 3 degrees to approximately 65 degrees (including, but not limited to, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12, 12.5, 13, 13.5, 14, 14.5, 15, 15.5, 16, 16.5, 17, 17.5, 18, 18.5, 19, 19.5, 20, 20.5, 21, 21.5, 22, 22.5, 23, 23.5, 24, 24.5, 25, 25.5, 26, 26.5, 27, 27.5, 28, 28.5, 29, 29.5, 30, 30.5, 31, 31.5, 32, 32.5, 33, 33.5, 34, 34.5, 35, 35.5, 36, 36.5, 37, 37.5, 38, 38.5, 39, 39.5, 40, 40.5, 41, 41.5, 42, 42.5, 43, 43.5, 44, 44.5, 45, 45.5, 46, 46.5, 47, 47.5, 48, 48.5, 49, 49.5, 50, 50.5, 51, 51.5, 52, 52.5, 53, 53.5, 54, 54.5, 55, 55.5, 56, 56.5, 57, 57.5, 58, 58.5, 59, 59.5, 60, 60.5, 61. 61.5, 62, 62.5, 63, 63.5, 64, 64.5, and / or 65 degrees).

[0080] The term “iron,” as used herein, can, in some embodiments, refer to an iron-type golf club head having a loft angle that is less than approximately 50 degrees, less than approximately 49 degrees, less than approximately 48 degrees, less than approximately 47 degrees, less than approximately 46 degrees, less than approximately 45 degrees, less than approximately 44 degrees, less than approximately 43 degrees, less than approximately 42 degrees, less than approximately 41 degrees, or less than approximately 40 degrees. Further, in many embodiments, the loft angle of the club head is greater than approximately 16 degrees, greater than approximately 17 degrees, greater than approximately 18 degrees, greater than approximately 19 degrees, greater than approximately 20 degrees, greater than approximately 21 degrees, greater than approximately 22 degrees, greater than approximately 23 degrees, greater than approximately 24 degrees, or greater than approximately 25 degrees.

[0081] In many embodiments, the golf club head can be an “iron-type” club head. Iron-type club heads as used herein includes a plurality of iron-type club head subsets, such as, but not limited to, high lofted wedges constructed for short-game shots and low lofted irons constructed for driving long-range shots, otherwise known as “crossovers.”

[0082] In many embodiments, the loft angle of the iron or wedge-type golf club head is less than approximately 50 degrees, less than approximately 49 degrees, less than approximately 48 degrees, less than approximately 47 degrees, less than approximately 46 degrees, less than approximately 45 degrees, less than approximately 44 degrees, less than approximately 43 degrees, less than approximately 42 degrees, less than approximately 41 degrees, or less than approximately 40 degrees. Further, in many embodiments, the loft angle of the golf club head is greater than approximately 16 degrees, greater than approximately 17 degrees, greater than approximately 18 degrees, greater than approximately 19 degrees, greater than approximately 20 degrees, greater than approximately 21 degrees, greater than approximately 22 degrees, greater than approximately 23 degrees, greater than approximately 24 degrees, or greater than approximately 25 degrees.

[0083] In many embodiments, the iron or wedge-type golf club head can comprise a total volume of between 1.9 cubic inches and 2.7 cubic inches. In some embodiments, the total volume of the golf club head can be between 1.9 cubic inches and 2.4 cubic inches, 2.0 cubic inches and 2.5 cubic inches, 2.1 cubic inches and 2.6 cubic inches, 2.2 cubic inches and 2.7 cubic inches, 2.3 cubic inches and 2.7 cubic inches, or 2.4 cubic inches and 2.7 cubic inches. In other embodiments, the total volume of the club head 100 can be 1.9 cubic inches, 2.0 cubic inches, 2.1 cubic inches, 2.2 cubic inches, 2.3 cubic inches, 2.4 cubic inches, 2.5 cubic inches, 2.6 cubic inches, or 2.7 cubic inches.

[0084] In many embodiments, the golf club head can comprise a total mass of between 200 grams and 300 grams. In some embodiments, the golf club head can comprise a total mass of between 200 grams and 210 grams, 210 grams and 220 grams, 220 grams and 230 grams, 230 grams and 240 grams, 240 grams and 250 grams, 250 grams and 260 grams, 255 grams and 260 grams, 260 grams to 270 grams, 265 grams to 275 grams, 270 grams and 280 grams, 275 grams and 280 grams, or 250 grams and 270 grams. In other embodiments, the total mass can be 200 grams, 205 grams, 210 grams, 220 grams, 225 grams, 230 grams, 235 grams, 240 grams, 245 grams, 250 grams, 255 grams, 260 grams, 265 grams, 270 grams, 275 grams, 280 grams, 285 grams, 290 grams, 295 grams, or 300 grams.DETAILED DESCRIPTION

[0085] Described herein is a golf club having a shortened hosel which reduces mass in the high heel area and creates discretionary mass. The golf club head described herein allows for a range of loft and lie adjustability post-manufacture with maintained or reduced surface deformation and durability loss and also creates discretionary mass that can be placed strategically for performance benefits. In some embodiments, an iron-type golf club head comprises a top rail opposite a sole, a toe end opposite a heel end, a face opposite a rear end, and a hosel. The hosel comprises a hosel bore configured to receive a shaft. The hosel bore is defined within the hosel and extends the entire length of the hosel and into the club body. By extending into the club head body, the hosel bore length remains sufficient to receive a shaft despite the shortened hosel length. The shortened hosel and lengthened hosel bore described below allow the golf club head loft and lie angles to be highly adjustable post-manufacture ±4°. Further, this design disperses stress over a greater surface area and reduces stress concentration at the site of highest bend. The improved bending capacity reduces risk of failure and mitigates the occurrence of undesirable stress marks. Furthermore, the lengthened hosel bore enables a shortened hosel length, freeing up discretionary mass. Alternative means of swing weighting, disclosed below, can eliminate the need for a “tip weight.” Eliminating the “tip weight” enables a further reduction in hosel length, removing mass from the heel end and allowing mass to be redistributed to locations more advantageous for increasing club head moment of inertia (MOI) such as a weighted badge or sole mass pads in the heel end and / or toe end of the club head.

[0086] Referring now to FIGS. 1-15, the club head 100 includes a club head body 104 having a toe 108 (or a toe end 108) opposite a heel 112 (or a heel end 112). The club head body 104 also includes a top rail 114 (or a crown 114) opposite a sole 115. A front 123 (or front side 123) of the club head body 104 carries a strike face 120 (or a face plate 120 or a club face 120 or a strike face 120) that defines a strike face front surface 122. The strike face 120 is opposite a rear 118 (or a back 118 or a rear side 118). The strike face 120 can also include a plurality of grooves 125.

[0087] With specific reference toFIG. 3, the club head body 104 also defines an upper portion 126 and a lower portion 128. An interior cavity opening perimeter 129 (for embodiments with an open interior cavity 175 as shown in FIGS. 16-37) or ledge 129 (for embodiments with a closed interior cavity 175 as shown in FIG. 3) is positioned on the rear 118 and extends generally from the toe 108 to the heel 112. The upper portion 126 is bounded by the top rail 114 and the ledge 129. The lower portion 128 is bounded by the sole 115 and the ledge 129.

[0088] With reference specifically to FIGS. 1B, 2 and 4, the strike face front surface 122 of the club head 100 includes the face center (FC). The face center (FC) can be located at a geometric center point of a strike face perimeter 105, and at a midpoint of a height of the strike face front surface 122. In some examples, the face center (FC) can be centered with respect to an engineered impact zone. The engineered impact zone can be defined by a region of grooves 125 on the strike face front surface 122. Alternatively, the face center (FC) can be located in accordance with a definition established by a golf governing body, such as the United States Golf Association (USGA).I. Hosel and Hosel Bore

[0089] With reference to FIGS. 1A, 1B, and 5A, and as stated above, the club head 100 also includes a hosel 110 positioned at the heel 112 for connecting the club head 100 to a shaft. Club heads constructed according to the present invention have a lengthened hosel bore 150, as described in further detail below. This lengthened hosel bore increases the surface area of the hosel 110. Distributing bending stresses over the increased surface area of the hosel 110 facilitates a greater degree of post-manufacture bendability (lie angle adjustability) without reduced risk of failure and mitigated occurrence of undesirable stress marks. Further, the lengthened hosel bore 150 facilitates a greater degree of post-manufacture bendability without the need for an aesthetically displeasing notch such as those found in conventional club heads.

[0090] The hosel 110 defines a hosel axis 1055 (FIGS. 1B, 5A, 9) that extends through a center of the hosel 110. The hosel 110 extends between a hosel bore proximal end 152 (or a proximal end 152) and a hosel bore distal end 154 (or a distal end 154) to the golf club head) from the club head body 104. The proximal end 152 of the hosel 110 is defined by a hosel outer transition plane 1038 (or transition plane 1038) at a location where an outer surface of the hosel 110 transitions to the club head body 104 (e.g., the heel 112), as shown in FIG. 5A. The hosel outer transition plane 1038 is perpendicular to the hosel axis 1055.

[0091] The hosel 110 includes a hosel bore 150. The hosel bore 150 extends along the hosel axis 1055 and is configured to receive the golf club shaft that carries a grip. As illustrated, the hosel bore 150 defines a proximal end 152 (or hosel bore proximal end 152) that is that is positioned within the club head body 104 (and specifically, the heel 112), and a distal end 154 (or a hosel bore distal end 154) that is positioned at the distal end of the hosel 110. The hosel bore distal end 154 is an open end and the hosel bore proximal end 152 is a closed end. The hosel bore proximal end 152 defines the lower boundary of the hosel 110 within the club head body 104 at the hosel bore proximal end 152. As noted above, and in contrast to typical golf club heads, the hosel bore 150 of the club head described herein extends beyond the proximal end 152 of the hosel 110 and into the club head body 104. To be specific, the hosel bore 150 extends beyond the hosel 110 (whose end can be identified by the hosel outer transition plane 1038 shown in FIG. 5A), and into the heel 112 of the club head body. Extending the hosel bore 150 beyond the hosel 110 is important for facilitating bending of the hosel 110 post manufacture, as discussed in further detail below.1. Hosel Bore Extension into Club Body

[0092] The hosel bore 150 extends the entire length of the hosel 110 and into the club head body 104 to allow for bending of the hosel 110 along a greater surface area. Therefore, the hosel bore 150 comprises a length that is greater than the length of the hosel 110. Referring to FIG. 5A, the hosel 110 defines a hosel length (HL) measured from the distal end 154 (or hosel bore distal end 154) to the transition plane 1038 along the hosel axis 1055. Depending on the club head loft and makeup, the hosel length (HL) ranges inclusively between 0.75 inches and 2.25 inches. In some embodiments, the hosel length (HL) ranges inclusively between 1.0 inches and 1.75 inches. In some embodiments, the hosel length (HL) can range between 0.75 inch and 1.0 inch, 1.0 inch and 1.25 inches, 1.25 inches and 1.50 inches, 1.50 inches and 1.75 inches, 1.75 inches and 2.0 inches, or 2.0 inches and 2.25 inches.

[0093] The hosel bore 150 defines a hosel bore height (HBH) measured from the hosel bore proximal end 152 (or hosel bore proximal end 152) to the hosel bore distal end 154 (or hosel bore distal end 154), which aligns with the hosel bore distal end 154, along the hosel axis 1055. In some embodiments, the hosel bore height (HBH) ranges inclusively between 1.0 inches and 2.5 inches. In some embodiments, the hosel bore height (HBH) ranges inclusively between 1.3 inches and 2.2 inches. In some embodiments, the hosel bore height (HBH) can range between 1.0 inch and 1.1 inches, 1.1 inches, and 1.2 inches, 1.2 inches and 1.3 inches, 1.3 inches and 1.4 inches, 1.4 inches and 1.5 inches, 1.5 inches and 1.6 inches, 1.6 inches and 1.7 inches, 1.7 inches and 1.8 inches, 1.8 inches and 1.9 inches, 1.9 inches and 2.0 inches, 2.0 inches and 2.1 inches, 2.1 inches and 2.2 inches, 2.2 inches and 2.3 inches, 2.3 inches and 2.4 inches, or 2.4 inches and 2.5 inches.

[0094] According to the present disclosure, the hosel length (HL) is less than the hosel bore height (HBH), resulting in the hosel bore 150 extending past the hosel 110 and into the club head body 104. Extending the hosel bore 150 into the club head body 104 by a distance defined by the difference between the hosel bore height (HBH) and (HL) removes material and mass from the heel 112, thereby increasing discretionary mass and facilitating post-production bending of the club head 100 by allowing for bending over a greater surface area. In many embodiments, the hosel bore height (HBH) is at least 100% the hosel length (HL). In some embodiments, the hosel bore height (HBH) may be approximately 100% to 160% greater than the hosel length (HL). For example, the hosel bore height (HBH) can be approximately 100% to 110%, 110% to 120%, 120% to 130%, 130% to 140%, 140% to 150%, or 150% to 160% greater than the hosel length (HL). In some embodiments, the hosel bore height (HBH) is at least 100%, at least 110%, at least 120%, at least 130%, at least 140%, or at least 150% greater than the hosel length (HL).

[0095] The position and configuration of the hosel 110 and the hosel bore 150 contrast with conventional iron-type golf club heads, one of which is shown in FIG. 6A. First, the hosel length (HL) ranges from between 0.200 and 0.600 inches less than the hosel length (HL) of conventional iron-type golf club heads. Moreover, the smaller hosel length (HL), together with the tapered first zone 186, which can receive a tip weight 156, reduces the overall mass of the club head 100 by between 3 grams and 8 grams. These differences lead to a lower center of gravity (CG). That is, as noted above, the center of gravity (CG) along the y-axis 1050 is approximately 0.020 inch to 0.060 inch lower than conventional iron-type golf club heads.2. Hosel Bore Internal Geometries

[0096] The geometry of the club head 100 may influence the shape of the hosel bore 150. More specifically, a heel-to-toe transition 124 of the club head 100 may have an arcuate shape. As the hosel bore 150 extends further into the club head 100, the hosel axis 1055 and the heel-to-toe transition 124 converge, reducing the amount of club head material therebetween and creating an area of stress concentration. To maintain structural integrity, the hosel bore proximal end 152 can be shaped to maintain sufficient club head material between the hosel bore 150 and the heel-to-toe transition 124. In some embodiments, the hosel bore 150 includes a hosel bore tip 155 that generally tapers toward the hosel bore proximal end 152. For example, as best shown in FIG. 9, the hosel bore tip 155 has a frustoconical shape with a larger diameter at the hosel bore distal end 154 and a smaller diameter at the hosel bore proximal end 152 configured to maintain structural integrity at the heel-to-toe transition 124. Specifically, because of the external geometry of the club head, wherein the heel end 112 below the hosel curves in toward the body, space for the hosel bore 150 in that region is limited, constraining the bore to be narrower. The tapered hosel bore tip 155 allows for a longer hosel bore 150, whose thinner walls allow for bending to occur further into the club head body and, therefore, over a greater surface area. The tapered hosel bore tip 155 also removes additional mass from the heel of the club head 100, thereby further increasing discretionary mass.

[0097] The hosel bore 150 can define multiple hosel bore walls 158 characterized by locations relative to the club head body 104. For example, the hosel bore walls 158 can be characterized by proximity to the toe 108 or heel 112 sides, respectively, as a toe-side internal wall 198 and a heel-side internal wall 194. In many embodiments, the toe-side internal wall 198 and the heel-side internal wall 194 can be formed and rounded continuously.

[0098] The toe-side internal wall 198 can define a toe-side hosel angle 196 relative to the hosel axis 1055. The heel-side internal wall 194 can define a heel-side hosel angle 192 relative to the hosel axis 1055. The angled configuration of the internal walls 198, 194 creates the tapered effect of the hosel bore proximal end 152. The toe-side hosel angle 196 can range inclusively between 2.5° and 20°. In some embodiments, the toe-side hosel angle 196 can range inclusively between 2.5° to 5.0°, 5.0° to 7.5°, 7.5° to 10.0°, 10.0° to 12.5°, 12.5° to 15°, 15° to 17.5°, or 17.5° to 20°. The heel-side hosel angle 192 can also range inclusively between 2.5° and 20°. In some embodiments, the heel-side hosel angle 192 can range inclusively between 2.5° to 5.0°, 5.0° to 7.5°, 7.5° to 10.0°, 10.0° to 12.5°, 12.5° to 15°, 15° to 17.5°, or 17.5° to 20°.

[0099] In many embodiments, the toe-side hosel angle 196 and the heel-side hosel angle 192 are the same. In alternative embodiments, the toe-side hosel angle 196 and the heel-side hosel angle 192 differ. In particular, the heel-side hosel angle 192 can be larger than the toe-side hosel angle 196. Internal walls with differing angles will create an asymmetrical shape. In all embodiments, the toe-side hosel angle 196 and the heel-side hosel angle 192 are likely to change, and become asymmetrical, as a result of hosel bending. Therefore, toe-side and heel-side hosel angles 196, 192 refer only to these angles post-manufacturing and before bending.3. Other Considerations of Hosel Bore Extension

[0100] Extending the hosel bore 150 into the club head body 104 increases discretionary mass that can be used elsewhere on the club head 100 to move a center of gravity (CG) of the club head 100 to a desired location. With reference to FIGS. 1B, 2, and 4, the location of the center of gravity (CG) can be defined relative to a coordinate system establishing the x-axis 1040, a y-axis 1050, and a z-axis 1060. The face center (FC) defines an origin of the coordinate system including the axes 1040, 1050, 1060. The x-axis 1040 (shown in FIGS. 1B and 2) extends through the club head face center (FC) from toe 108 to the heel 112. The x-axis 1040 is positive towards the toe 108. The y-axis 1050 (shown in FIGS. 1B and 4) extends through the club head face center (FC) from the top rail 114 (or crown 114) to the sole 115. The y-axis 1050 is positive towards the top rail 114 (or crown 114). The y-axis 1050 is perpendicular to the x-axis 1040 when viewed from the front view (or from the strike face 120). The y-axis 1050 is oriented at an oblique angle to the hosel axis 1055. The z-axis 1060 (shown in FIGS. 2 and 4) extends through the face center (FC) from the strike face 120 to the rear 118 of the club head 100. The z-axis 1060 is positive towards the strike face 120. The z-axis 1060 is perpendicular to the x-axis 1040 and the y-axis 1050.

[0101] In the illustrated embodiment, the location of the center of gravity (CG) can be measured from the face center (FC). The center of gravity (CG) can be measured along the x-axis 1040 relative to the face center (FC) and is represented by CGx. The center of gravity (CG) can also be measured along the y-axis 1050 relative to the face center (FC) and is represented by CGy. The center of gravity (CG) can be measured along the z-axis 1060 face center (FC) and is represented by CGz. Moving the center of gravity (CG) towards the toe 108 or the heel 112 can be achieved by increasing or decreasing the distance along the x-axis 1040. Lowering the center of gravity (CG) can be achieved by decreasing the distance along the y-axis 1050. Moving the center of gravity (CG) rearward can be achieved by increasing the distance along the z-axis 1060. In other examples of embodiments, the center of gravity (CG) location can be measured from the leading edge 133 of the club head 100 (or from a furthest forward position of the club head 100).

[0102] In some embodiments, the center of gravity (CG) may be approximately aligned with the face center (FC) along the x-axis 1040 (i.e., CGx is approximately zero). In other embodiments, CGx may be located approximately-0.10 inches to approximately 0.10 inches from the face center (FC), as measured along the x-axis 1040. The club head 100 also has a CGy of approximately 0.10 inches to approximately 0.75 inches from the face center (FC), as measured along the y-axis 1050. In the illustrated embodiment, the CGy is between the face center (FC) and the sole 115. As a result of the hosel 110 position and configuration, the CGy is between 0.020 inch and 0.060 inch lower than conventional iron-type golf club heads (shown in FIG. 9A). As illustrated in Example 1 below, the CGy can be approximately 0.040 inches lower than in conventional iron-type golf club heads.

[0103] The hosel bore further can be characterized by a total bore volume. The total bore volume can be categorized into an upper bore volume and a lower bore volume with respect to other elements of the club head. For example, the bore volume can be categorized by an upper bore volume above the hosel outer transition plane 1038 and a lower volume below the hosel outer transition plane 1038. In some embodiments, the upper bore volume above the hosel outer transition plane 1038 is 60-95% of the total bore volume and the lower bore volume below the hosel outer transition plane 1038 is 5-40% of the total bore volume. For example, the upper bore volume above the hosel outer transition plane 1038 can be 60-65%. 65-70%, 70-75%, 75-80%, 80-85%, 85-90%, or 90-95% of the total bore volume. The lower bore volume below the hosel outer transition plane 1038 can be 5-10%, 10-15%, 15-20%, 20-25%, 25-30%, 30-35%, or 35-40% of the total bore volume. As illustrated in Example 1 below, the upper bore volume above the hosel outer transition plane 1038 can be 90% of the total bore volume and the lower bore volume below the hosel outer transition plane 1038 can be 10% of the total bore volume.

[0104] The hosel bore 150 can be measured with reference to a plurality of axes formed across the club head 100 and parallel to the ground plane 160, as illustrated in FIGS. 7 & 8. It is beneficial for the hosel bore 150 to extend into the club head body 104 below particular reference planes in order to reduce overall club mass, create discretionary mass for performance benefits, and ensure the hosel 110 is able to withstand bending up to ±6° without substantial surface deformation or wrinkling. In some examples, the hosel 110 is able to withstand bending up to ±2°, ±3°, ±4°, ±5°, or ±6°.

[0105] The upper bore volume and lower bore volume can be quantified by referencing the plurality of axes. In the address position, a first axis 1010 (hereafter referred to as “top-hosel axis”1010) is formed parallel to the ground plane 160 across the top-most edge of the hosel 110. A hosel height (HH) can be defined as the distance from the ground plane 160 to the top-hosel axis 1010. In some embodiments, the hosel height (HH) ranges inclusively between 1.5 inches and 2.75 inches. In many embodiments, the hosel height (HH) can range inclusively between 1.75 inches and 2.25 inches. For example, the hosel height (HH) can range inclusively between 1.75 inches and 1.85 inches, 1.85 inches and 1.95 inches, 1.95 inches and 2.05 inches, 2.05 inches and 2.15 inches, or between 2.15 inches and 2.25 inches. The hosel height (HH) can be approximately 5% to approximately 25% lower than the hosel height of conventional club heads. In some embodiments, the hosel height (HH) is 5-10%, 10-15%, 15-20%, or 20-25% lower than a hosel height of conventional club heads. As detailed in Example 1 below, the hosel height (HH) can be 8.6% lower than the hosel height (HH) of conventional club heads. In another embodiment of an exemplary club head, the hosel height (HH) can be 8.8% lower than the hosel height of conventional club heads.

[0106] In the address position, a second axis 1012 (hereafter referred to as “hosel-body axis”1012) is formed parallel to the ground plane 160 across the location at which the hosel 110 and club head body 104 meet. A hosel-body bore height 1017 can be defined between the ground plane 160 and the hosel-body axis 1012. The hosel bore volume can be characterized further by the percent of total volume that resides above or below the hosel-body axis 1012. In particular, a percentage of the hosel bore volume can be located below the hosel-body axis 1012. In some embodiments, the percentage of the hosel bore volume below the hosel-body axis 1012 can range inclusively between 5% and 40% of the hosel bore volume. In many embodiments, the percentage of the hosel bore volume below the hosel-body axis 1012 can range inclusively between 5% and 30% of the hosel bore volume. In some embodiments, the percentage of the hosel bore volume below the hosel-body axis 1012 is 5%-10%, 10%-15%, 15%-20%, or 20%-25% of the hosel bore volume.

[0107] A hosel-body ratio can be defined as the ratio between the percentage of the hosel bore volume above the hosel-body axis 1012 and the percentage of the hosel bore volume below the hosel-body axis 1012. In some embodiments, the hosel-body ratio, H1:H2, is approximately 1.5:0.025 to 1.5:0.250. In some embodiments, the hosel-body ratio H1:H2 can be between 1.5:0.025 and 1.5:0.050, 1.5:0.050 and 1.5:0.075, 1.5:0.075 and 1.5:0.100, 1.5:0.100 and 1.5:0.125, 1.5:0.125 and 1.5:0.150, 1.5:0.150 and 1.5:0.175, 1.5:0.175 and 1.5:0.200, 1.5:0.200 and 1.5:0.225, or 1.5:0.225 and 1.5:0.250.

[0108] In the address position, a third axis 1014 (hereafter referred to as “midline axis”1014) is formed parallel to the ground plane 160 across the geometric middle of the club head body 104. A midline hosel bore height 1015 of the hosel bore can be defined between the ground plane 160 and the midline axis 1014. A percentage of the hosel bore volume can be located below the midline axis 1014. In some embodiments, the percentage of the hosel bore volume below the midline axis 1014 can range inclusively between 1% and 20% of the hosel bore volume. In many embodiments, the percentage of the hosel bore volume below the midline axis 1014 can range inclusively between 1% and 15% of the hosel bore volume. In some embodiments, percentage of the hosel bore volume below the midline axis 1014 is 1%-5%, 5%-10%, or 10%-15% of the hosel bore volume.

[0109] The extension of the hosel bore 150 into the club head body 104 lowers the center of gravity (CG), reduces mass of the club head to create discretionary weight, and allows for the design to comprise a shortened hosel 110, which further reduces mass. Further, positioning the hosel bore 150 low within the club head body 104 ensures the bend point of the hosel 110 occurs where the wall thickness can withstand an increased amount of stress and allows bending to occur over a greater surface area, reducing the occurrence of highly concentrated stress. Therefore, the low position of the hosel bore 150 allows the club head 100 to be bent to a relatively high degree during loft and lie adjustments without the formation of visible stress marks or surface deformation.

[0110] In the address position, a fourth axis 1016 (hereafter referred to as “bottom-hosel axis”1016) is formed parallel to the ground plane 160 across the bottom-most edge of the hosel bore 150. A lower hosel bore height 1013 can be defined as the distance from the ground plane 160 to the bottom-hosel axis 1016. In some embodiments, the lower hosel bore height 1013 ranges inclusively between 0.25 inches and 1.0 inches. In many embodiments, the lower hosel bore height 1013 ranges inclusively between 0.25 inches and 0.75 inches. In some embodiments, the lower hosel bore height 1013 ranges between 0.25 inches and 0.35 inches, 0.35 inches and 0.45 inches, 0.45 inches and 0.55 inches, 0.55 inches and 0.65 inches, or between 0.65 inches and 0.75 inches. The lower hosel bore height 1013 can be approximately 40% to approximately 80% lower than a hosel bore of conventional club heads. In some embodiments, the lower hosel bore height 1013 is 40-50%, 50-60%, 60-70%, or 70-80% lower than a lower hosel bore height of conventional club heads. As discussed in Example I below, the lower hosel bore height 1013 can be 57.1% lower than a lower hosel bore height of a conventional club head. As discussed in Example I below, the lower hosel bore height 1013 can be 65.1% lower than a lower hosel bore height of another conventional club head.

[0111] A hosel-bore ratio can be defined as the ratio of hosel height (HH) to lower hosel bore height 1013. As discussed above, it is desirous for bending purposes to have a hosel bore 150 which extends into the club head body 104 while maintaining a shortened hosel height (HH). A large hosel-bore ratio is indicative of a hosel which has both a high surface area and shortened hosel height and is therefore an indication that a club head will be suitable for post-manufacture bending. In some embodiments disclosed herein, the hosel-bore ratio is 1.2:1.1 to 1.9:1.0. In many embodiments, the hosel-bore ratio is 1.25:1.15 to 1:75:1.1. The hosel bore 150 is longer than the hosel 110 and extends into the club head body 104. This hosel bore configuration removes mass in the upper portion 126 of the club head body 104 and lowers the overall center of gravity (CG), creating discretionary mass to further be applied for weight benefits. The extended hosel bore 150 allows for bending to occur further into the club head body, allowing for increased distribution of stress over a greater surface area. By extending the hosel bore 150 lower into the club head body 104, the walls at the hosel-body connection point and heel 112 are thinned, thus allowing for hosel 110 bending without displaying high stress marks. The lowered bore design maintains the ability to post-manufacture adjustments to loft and lie, while mitigating or completely avoiding the generation of visible stress marks and creates discretionary mass for club head performance benefits.4. Hosel Configurations

[0112] The thickness of the hosel walls affects the ability of the hosel to undergo post-manufacture bending and withstand accompanying stresses. With reference to FIGS. 5A and 9-12, the hosel bore 150 defines a hosel bore wall 158. Different regions of the hosel bore wall 158 located sequentially along its hosel bore height (HBH) have associated thicknesses T1, T2, T3 that are measured from an inner surface of the hosel bore 150 to an outer surface of the hosel 110 and / or to the heel 112. The thicknesses of the hosel bore wall 158 generally decrease from the proximal end 152 of the hosel bore 150 to the distal end 154 of the hosel bore 150. That is, the hosel bore wall 158 at the proximal end 152 has the first wall thickness T1 that is the greatest thickness, the hosel bore wall 158 at the distal end 154 has second thickness T2 that is the smallest thickness, and the hosel bore wall 158 between the proximal end 152 and the distal end 154 has a third thickness T3 that is smaller than the first thickness T1 and greater than the second thickness T2. In other words, the hosel bore wall 158 has a first zone 186, a second zone 188, and a third zone 190.

[0113] In FIG. 5A, the different zones 186, 188, 190 are indicated using dash-dot lines. These zones are merely exemplary and may be delineated in other ways. The first zone 186 is configured to at least partially receive the tip weight 156. In the illustrated embodiment, the entire tip weight 156 is positioned within the first zone 186. In some embodiments, the tip weight 156 may be positioned in both the first zone 186 and the third zone 190. The first zone 186 has the first wall thickness T1. The second zone 188 has the second wall thickness T2. The third zone 190 has the third wall thickness T3.

[0114] The thickness T1 of the hosel bore wall 158 is not uniform in the first zone 186 for two reasons. First, in some embodiments, at least a portion of the hosel bore wall 158 can be tapered relative to the hosel axis 1055, and second, a portion of the hosel bore wall 158 is made up of the heel 112, which has a curved exterior profile, and another portion of the hosel bore wall 158 nears the top rail 114, requiring additional material for structural stability. The first wall thickness T1 is larger on a top side of the hosel bore wall 158 than in the remainder of the hosel bore wall 158.

[0115] With reference to FIG. 10, to relate the thicknesses T1, T2, T3 of the hosel 110, the hosel bore 150 and hosel bore wall 158 can be compared to an analog clock in which a xh-axis 1045 extends between 12 o'clock and 6 o'clock, and a zh-axis 1065 extends between 3 o'clock and 9 o'clock. As shown, the xh-axis 1045 of the clock is parallel to and offset relative to an x-axis 1040 extending through a face center (FC) of the club head 100. In the illustrated embodiment, in the first zone 186, the thickness T1 of the hosel bore wall 158 is greatest between 12 o'clock and 3 o'clock because this is where the club head body 104 defines the hosel bore wall 158. Moreover, although not illustrated in FIGS. 10-12, the thickness T1 of the hosel bore wall 158 may generally decrease from the location between the first zone 186 and the third zone 190 in a direction toward the proximal end 152 of the hosel bore 150 and the club head body 104 in a region between 4 o'clock and 7 o'clock because this is where the exterior surface that transitions from the hosel 110 to the heel 112 is generally located. As shown, in FIGS. 11 and 12, the thicknesses T2 and T3 are generally uniform around the clock, with the thickness T3 being smaller than the thickness T2.

[0116] By maintaining a consistent wall thickness T2, T3 in the second zone 188 and third zone 190 and placing the proximal end 152 of the hosel bore 150 in the club head body 104, stress is distributed more evenly along the hosel length (HL), which leads to less localized stress and better bending results.

[0117] For additional guidance in describing the innovation herein, the x-axis 1040 and the z-axis 1060 are arranged to coincide with numbers on an analog clock in FIGS. 10-12. The z-axis 1060 extends between 12 o'clock (“12” through the strike face 120) and 6 o'clock (“6” through the rear 118), and the x-axis 1040 extends between 3 o'clock (“3” through the toe end 108) and 9 o'clock (“9” through the heel end 112), as also described above.

[0118] The first wall thickness T1 may range from approximately 0.05 inches to approximately 0.50 inches. The second wall thickness T2 may range from approximately 0.03 inches to approximately 0.3 inches. The third wall thickness T3 may range from approximately 0.02 inches to approximately 0.25 inches. The bore wall thicknesses T1, T2, T3 of each zone 186, 188, 190 may correspond to the type of the material of the club head body 104.

[0119] The respective thicknesses T1, T2, T3 of the hosel bore wall 158 in the different zones 186, 188, 190 are shown in greater detail in FIGS. 5A and 9-12. First, as shown in FIG. 5A, the thickness T1 of the hosel bore wall 158 in the first zone 186 on the heel end 112 corresponds to an exterior surface that transitions from the hosel 110 to the heel 112. Accordingly, as the exterior surface on the heel side transitions from the hosel 110 to the heel 112, the thickness T1 of the hosel bore wall 158 in the first zone 186 narrows. In other words, the thickness T1 of the hosel bore wall 158 is lowest on the heel end 112 at a location between the first zone 186 and the third zone 190 and smallest at the proximal end 152 of the hosel bore 150. Additionally, on the heel end 112, the thickness T1 of the hosel bore wall 158 narrows in a direction from the location between the first zone 186 and the third zone 190 in a direction toward the proximal end 152 of the hosel bore 150. Moreover, as shown, the hosel bore wall 158 of the first zone 186 is tapered relative to the hosel axis 1055 in some embodiments. The heel-side hosel angle 192 of taper between the hosel bore wall 158 and the hosel axis 1055 may range from approximately 2.5° to 5.0°, 5.0° to 7.5°, 7.5° to 10.0°, 10.0° to 12.5°, 12.5° to 15°, 15° to 17.5°, or 17.5° to 20°.

[0120] Further, with respect to FIGS. 10-12, different internal zones 186, 188, 190 of the hosel bore 150 define a first bore diameter 1030, second bore diameter 1032, and third bore diameter 1034 (e.g., diameters 1030, 1032, 1034) and the outer surface of the hosel 110 and the heel 112 defines a second dimension 1036. The bore diameters 1030, 1032, 1034 of the hosel bore 150 generally decrease from the proximal end 152 of the hosel bore 150 to the distal end of the hosel bore 150. That is, the hosel bore 150 at the proximal end 152 has a first bore diameter 1030 that is the largest diameter, the hosel bore 150 at the distal end 154 has a second bore diameter 1032 that is the smallest diameter, and the hosel bore 150 between the distal end 154 and proximal end 152 has a third bore diameter 1034 that is smaller than the first bore diameter 1030 and greater than the second bore diameter 1032. Also, correspondingly, the first bore diameter 1030 of the first zone 186 generally increases from the hosel bore proximal end 152 in a direction toward the hosel bore distal end 154. The second bore diameter 1032 is generally constant in the second zone 188 and third zone 190 (and around the clock defined by hosel axes 1045, 1065), but the second bore diameter 1032 is not constant in the first zone 186 because the first zone 186 has an oblong shape (as a result of the various thicknesses discussed above relative to the clock defined by hosel axes 1045, 1065). In other words, the first zone 186 has the first bore diameter 1030 and the variable second dimension 1036, the second zone 188 has the second bore diameter 1032 and a constant second dimension 1036, and the third zone 190 has the third bore diameter 1034 and a constant second dimension 1036, which is the same as the constant second dimension 1036 of the second zone 188.

[0121] The first bore diameter 1030 may range from approximately 0.05 inches to approximately 0.50 inches. The second bore diameter 1032 may range from approximately 0.25 inches to approximately 0.75 inches. The third bore diameter 1034 may range from approximately 0.10 inches to approximately 0.60 inches. The second dimension 1036 may range from approximately 0.50 inches to approximately 1.0 inches in the first zone 186, and the second dimension 1036 may range from approximately 0.25 inches to approximately 0.85 inches in the second zone 188 and third zone 190. Accordingly, the first bore diameter 1030 may be approximately 5% to approximately 50% of the largest second dimension 1036 of the first zone 186 and from approximately 20% to approximately 90% of the smallest second dimension 1036 of the first zone 186. The second bore diameter 1032 may be approximately 25% to approximately 90% of the second dimension 1036. The third bore diameter 1034 may be approximately 25% to approximately 90% of the second dimension 1036. The bore diameters 1030, 1032, 1034 and the second dimension 1036 are determined at least in part according to the type of the material of the club head body 104.

[0122] As shown in FIGS. 10-12, in illustrated embodiments, both the hosel 110 and the hosel bore 150 have circular cross-sections. That is, the second zone 188 and third zone 190 and the hosel bore 150 have circular cross-sections. In other embodiments, the hosel 110 may have a cross-section with a different shape and therefore the first zone 186 and second zone 188 may have cross-sections with a different shape. For example, the hosel 110 (and the second zone 188 and third zone 190 thereof) may have an ovular or elliptical cross-section. This modification would change the relative bore wall thicknesses T1, T2, T3 and the second dimension 1036 of the second zone 188 and third zone 190.

[0123] In alternative embodiments, as illustrated in FIGS. 14 and 15, the hosel bore can be formed continuously with an enclosed cavity within the body of the club head. As shown in the embodiment of FIG. 14, the cavity can extend partially into the club head and can be formed as part of a cavity back or muscle back iron-type club head, or could be used within a wedge, crossover, or putter. As shown in the embodiment of FIG. 15, the cavity can extend throughout the entirety of the club head body, forming a hollow-body iron-type club head. In these embodiments, the hosel bore can be open to the cavity, such that the hosel bore and cavity together form a single void. In other embodiments, the hosel bore and the cavity can be sectioned off with a partial or complete wall.

[0124] The partial cavity of the club head shown in FIG. 14 extends to align with a heel-most edge of the strike face in the illustrated embodiment. In other embodiments, the partial cavity can extend to a point heelward or toeward of the strike face edge. The shape and size of the cavity can be formed to best distribute stresses during hosel bending and during impact with a golf ball.

[0125] A thickness of the walls surrounding both the hosel bore and the enclosed cavity are illustrated to be consistent throughout. In other embodiments, however, the walls may comprise varying thickness which may taper or include thickened regions to provide necessary structural strength and rigidity, to improve manufacturability, or to encourage bending only in desired regions.

[0126] In some embodiments, the strike face 120 can comprise a first material of a first density. The club head body 104 can comprise a second material of a second density. In the illustrated embodiment, the strike face 120 can be the same material as the club head body 104 (and thereby the same densities).

[0127] The club head body 104 may comprise a material, such as steel, a steel alloy, or any other suitable material. In some embodiments, the club head body 104 can comprise a material of a density that is different over the strike face 120. The density of the club head body 104 material can range between 7.70 and 8.10 grams per cubic centimeter (hereafter “g / cc”). In some embodiments, the density of the body material can be 7.70 g / cc, 7.75 g / cc, 7.80 g / cc, 7.85 g / cc, 7.90 g / cc, 7.95 g / cc, 8.05 g / cc, or 8.10 g / cc.

[0128] The material of the club head body 104 can comprise a hardness measured on the Rockwell Scale (HRC). In many embodiments, the material hardness is related to the wall thicknesses T1, T2, T3 and bore diameters 1030, 1032, 1034 of the hosel 110. A club head comprising a material with a lower hardness will require a thicker area to reduce the appearances of stress bending. In order to maintain a similar degree of force required to bend the hosel, a golf club head made of a material with a greater hardness will require thinner hosel walls than a golf club head made of a material with a lower hardness. This is because a harder material will require greater force to incur deformation. It is preferable to establish a uniform assembly process by requiring a nearly constant amount of force to bend the hosel by modifying the wall thickness as needed based on material properties. Example V below details further the relationship between material hardness and hosel wall thickness.

[0129] In addition to the relational position of the hosel bore 150, other features of the club head 100 dictate performance characteristics such as the moments of inertia Ixx, Iyy and center of gravity (CG). The materials that form the club head body 104, the strike face 120, the toe weight 157, and the tip weight 156 can affect the mass distribution of the club head 100. Consequently, the moments of inertia Ixx, Iyy and center of gravity center of gravity (CG) of the club head 100 are also affected by the densities of the materials. Furthermore, the materials provide the strength and flexibility necessary for the club head 100. The club head 100 comprises one or more, two or more, three or more, or four or more materials. In some embodiments, the materials may be a first density, second density, third density, fourth density, fifth density or sixth density.

[0130] Moreover, because a portion of the hosel bore 150 extends into the club head body 104 (or heel 112), a portion of the tip weight 156 can reside partially or entirely within the club head body 104, when only a portion of the tip weight 156 resides in the club head body 104, a remainder of the tip weight 156 can reside in the hosel 110. The weight of the tip weight 156 can range between 0 grams and 18 grams. In some embodiments, the weight of the tip weight 156 can be 0 grams (in the embodiment where there is no tip weight), 1 grams, 2 grams, 3 grams, 4 grams, 5 grams, 6 grams, 7 grams, 8 grams, 9 grams, 10 grams, 11 grams, 12 grams, 13 grams, 14 grams, 15 grams, 16 grams, 17 grams, or 18 grams. In some embodiments, the tip weight 156 ranges between 0 grams and 9 grams. The tip weight 156 can comprise a material that is different over the material of the club head body 104. The tip weight 156 may be formed from the same or different material as the toe weight 157 and therefore comprises a high-density material, such as tungsten or any other suitable metal or metal alloy material.

[0131] In some embodiments, the density of the material(s) of the toe weight 157 and the tip weight 156, if present, can range between 1.1 g / cc and 19.6 g / cc. In some embodiments, the density of the tip weight 156 material can be 1.1 g / cc, 1.5 g / cc, 2.0 g / cc, 2.5 g / cc, 3.0 g / cc, 3.5 g / cc, 4.0 g / cc, 4.5 g / cc, 5.0 g / cc, 5.5 g / cc, 6.0 g / cc, 6.5 g / cc, 7.0 g / cc, 7.5 g / cc, 8.0 g / cc, 8.5 g / cc, 9.0 g / cc, 9.5 g / cc, 10.0 g / cc, 10.5 g / cc, 11.0 g / cc, 11.5 g / cc, 12.0 g / cc, 12.5 g / cc, 13.0 g / cc, 13.5 g / cc, 14.0 g / cc, 14.5 g / cc, 15.0 g / cc, 15.5 g / cc, 15.8 g / cc, 16.0 g / cc, 16.2 g / cc, 16.4 g / cc, 16.6 g / cc, 16.8 g / cc, 17.0 g / cc, 17.2 g / cc, 17.4 g / cc, 17.6 g / cc, 17.8 g / cc, 18.0 g / cc, 18.2 g / cc, 18.4 g / cc, 18.6 g / cc, 18.8 g / cc, 19.0 g / cc, 19.2 g / cc, 19.4 g / cc, or 19.6 g / cc.

[0132] With specific reference to FIG. 4, a vertical plane 1020 is illustrated to show hosel tilt relative to the club head body. The vertical plane 1020 is an imaginary plane that is generally perpendicular to a ground surface in response to the club head body 104 being at an address position. The vertical plane 1020 is tangent to a leading edge 133 (or forwardmost edge 133) of the club head 100 and perpendicular to a ground plane 160. The hosel axis 1055 is oriented at an angle relative to the vertical plane 1020. Stated another way, the hosel axis 1055 is oriented oblique to the vertical plane 1020. The hosel axis 1055 and the vertical plane 1020 define a first angle 1018. The first angle 1018 is representative of the hosel tilt. In the illustrated embodiment, the hosel tilt (or first angle 1018) is approximately 0.25 degrees to approximately 20 degrees, and more specifically approximately at least 5.0 degrees. The hosel tilt is oriented such that the hosel axis 1055 extends away from the vertical plane 1020. The hosel axis 1055 is configured to intersect the vertical plane 1020 at an imaginary position below the ground surface. This hosel tilt, or negative hosel tilt relative to the vertical plane 1020 allows the player to position their hands behind the ball (or towards a trailing or rear foot of the player) at the address position. It should be appreciated that at the address position, the club head body 104 is in contact with the ground. More specifically, the sole 115 (or a portion of the sole 115) is in contact with the ground.

[0133] With continued reference to FIG. 4, the club head 100 includes an impact force line 1035. The impact force line 1035 can be a force line that extends through a center of a golf ball when impacted by the strike face front surface 122. The impact force line 1035 can be perpendicular to the strike face 120, and more specifically perpendicular to the strike face front surface 122. In some embodiments, the impact force line 1035 can extend through the face center (FC) of the strike face front surface 122.

[0134] As noted above, bending the hosel 110 relative to the club head body 104 (via hammering and the like) adjusts the loft angle and the lie angle. The position and configuration of the hosel 110 and the hosel bore 150 spread the stress of the bending process over a longer length of the hosel 110, while also reducing the stress on other areas of the club head body 104. During bending, stress concentrates at the corners of the hosel bore proximal end 152. The hosel bore proximal end 152, as shown in FIGS. 1A & 5A, defines the lowest location of the hosel bore 150 on the hosel 110. By lowering the location of the hosel bore proximal end 152, the stress is spread over a broader wall and thereby reduces the maximum stress at any given location. However, the club head 100 maintains the ability to be adjusted for loft and lie up to ±4 degrees, ±2 degrees more than a traditional golf club head.II. Cavity-Back Golf Club Heads with Open Interior Cavity

[0135] As discussed above, extending the hosel bore into the club head body by a distance defined by the difference between the hosel bore height (HBH) and (HL) removes material and mass from the heel, thereby increasing discretionary mass. In some embodiments, discretionary mass can be further increased by eliminating the tip weight enabling a shorter hosel bore height (HBH). For embodiments that omit a tip weight, swing weighting can be accomplished by incorporating weight members into the rear of the club head. “Cavity-back” golf club heads, such as the golf club heads illustrated in FIGS. 16-37, can incorporate an insert that harbors a plurality of weight members for swing weighting, as discussed in further detail below.

[0136] A cavity-back golf club head, having an open interior cavity, is illustrated in FIGS. 16-27. The club head body 204 comprises a strike face 220, a top rail 214, a sole 215 opposite the top rail 214, a toe end 208, and a heel end 212 opposite the toe end 208. The strike face 220 further comprises a strike face rear surface 223 and a strike face front surface 222 opposite the strike face rear surface 223. The strike face 220 further comprises a strike face perimeter 205 which defines an outer boundary of the strike face 220.

[0137] The top rail 214, sole 215, toe end 208, and heel end 212 each extend rearwardly from the strike face perimeter 205. The sole 215 comprises a sole inner surface 217 which extends from the strike face perimeter 205 on the strike face rear surface 223 to the interior cavity opening perimeter 229. The interior cavity opening perimeter 229 is defined as the junction between the exterior surface 280 of the club head body 204 and the interior surface 281 of the club head body 204. The sole inner surface 217 defines an interior cavity base 276, and an interior surface of the top rail 214 defines an interior cavity top 277. The sole 215 further comprises a sole exterior surface 219, which extends from the leading edge 233 to the interior cavity opening perimeter 229. The club head body 204 further comprises a hosel 210 located proximate the heel end 212 and configured to receive a shaft.

[0138] As illustrated in FIGS. 26-27, the golf club head further comprises a coordinate system centered about the face center (FC). The coordinate system comprises an X-axis 2040, a Y-axis 2050, and a Z-axis 2060. The X-axis 2040 extends in a heel-to-toe direction. The X-axis 2040 is positive towards the heel end 212 and negative towards the toe end 208. The Y-axis 2050 extends in a sole-to-top rail direction and is orthogonal to the X-axis 2040. The Y-axis 2050 is positive towards the top rail and negative towards the sole. The Z-axis 2060 extends in a direction from a front end to a rear end of the golf club head. The Z axis 2060 is perpendicular to both the X-axis 2040 and the Y-axis 2050.

[0139] As illustrated in FIGS. 26-27, the golf club head comprises a coordinate system centered about the center of gravity (CG). The coordinate system comprises an X′-axis 2070, a Y′-axis 2080, and a Z′-axis 2090. The X′-axis 1070 extends in a heel-to-toe direction. The X′-axis 2070 is positive towards the heel end 212 and negative towards the toe end 208. The Y′-axis 2080 extends in a sole-to-top rail direction and is orthogonal to the X′-axis 2070. The Y′-axis 2080 is positive towards the top rail and negative towards the sole. The Z′-axis 2090 extends in a direction from a front end to a rear end of the golf club head. The Z′ axis 2090 is perpendicular to both the X′-axis 2070 and the Y′-axis 2080.1. Strike Face Geometry

[0140] The strike face geometry can be designed to improve ball speed and accommodate the insert, as discussed in further detail below. The strike face 220 can have a strike face thickness 240, measured from the strike face rear surface 223 to the strike face front surface 222 in a direction perpendicular to the loft plane 2022. In some embodiments, the strike face thickness 240 can vary in a top rail 214 to sole 215 direction and / or a heel end 212 to toe end 208 direction. For embodiments where the strike face thickness is variable, the strike face thickness 240 can include a maximum value (maximum strike face thickness) and a minimum value (minimum strike face thickness).

[0141] In some embodiments, the strike face 220 can comprise a strike face thickness between 0.050 and 0.150 inch. In some embodiments, the strike face thickness can be 0.050 and 0.058 inch, between 0.058 and 0.066 inch, between 0.066 and 0.074 inch, between 0.074 and 0.082 inch, between 0.082 and 0.090 inch, between 0.090 and 0.098 inch, between 0.098 and 0.106 inch, between 0.106 and 0.114 inch, between 0.114 and 0.122 inch, between 0.122 and 0.130 inch, between 0.130 and 0.138 inch, between 0.138 and 0.150 inch. The strike face thicknesses disclosed herein can apply to a maximum strike face thickness, a minimum strike face thickness, or any thickness located within the strike face perimeter.

[0142] In some embodiments, the strike face 220 can comprise a difference between the maximum strike face thickness and the minimum strike face thickness. In some embodiments the minimum strike face thickness can be between 80% and 95% of the maximum strike face thickness. In other embodiments the minimum strike face thickness can be between 25% and 30%, 30% and 35%, 35% and 40%, 40% and 45%, 45% and 50%, 50% and 55%, 55% and 60%, 60% and 65%, 65% and 70%, 70% and 75%, 75% and 80%, 80% and 85%, 85% and 90%, or 90% and 95% of the maximum strike face thickness.

[0143] The strike face 220 defines a face center (FC), which is the geometric centerpoint of the strike face perimeter, as illustrated in FIGS. 26 and 27. The face center (FC) has a face center height (HFC) defined as the distance between the face center (FC) and the ground plane 260 measured along the Y-axis 2050. The strike face 220 further comprises a plurality of grooves 225 extending in a heel end 212 to toe end 208 direction parallel to the ground plane 260. The strike face 220 can have a strike face perimeter 205. The strike face perimeter 205 is defined where the strike face front surface 222 deviates from the loft plane 2022 proximate the heel end 212, toe end 208, top rail 214, and sole 215. The strike face perimeter 205 includes at least an upper edge 241 and a leading edge 233. The upper edge 241 is the portion of the strike face perimeter 205 proximate the top rail and defines a transition from the strike face 220 to the top rail 214. The upper edge 241 defines a face apex (FA), located at the point along the upper edge 241, which is furthest from the face center along the Y-axis 2050. The leading edge 233 is the most soleward portion of the strike face perimeter and delineates a boundary between the strike face 220 and the sole 215. The leading edge 233 defines a face nadir (FN), located at the point along the leading edge 233 which is furthest from the face center along the Y-axis 2050. The strike face 220 defines a face height (HSF) defined as the distance between the face apex (FA) and the face nadir (FN) measured along the Y-axis 2050. The strike face 220 defines a face center width (WFC), defined as the distance between a heel end 212 of the strike face perimeter 205 and toe end 208 of the strike face perimeter 205 measured parallel to the loft plane 2022 at the face center height (HFC).

[0144] In some embodiments, the face height (HSF) can be between 1.5 and 2.2 inches. In some embodiments, the face height (HSF) can be between 1.5 and 1.8 inches, between 1.6 and 1.9 inches, between 1.7 and 2.0 inches, between 1.8 and 2.1 inches, between 1.9 and 2.2 inches, between 2.0 and 2.3 inches, or between 2.1 and 2.4 inches.

[0145] A shorter face height (HSF) lowers the face center (FC) closer to the ground plane 160. Lowering the face center (FC) can be advantageous for players who want to increase the launch angle of their golf ball. In some embodiments, the face center height (HFC) can be between 0.70 and 1.1 inches. In some embodiments, the face center height (HFC) can be between 0.7 and 0.8 inch, between 0.8 and 0.9 inch, between 0.9 and 1.0 inches, or between 1.0 and 1.1 inches.

[0146] In some embodiments, the face center width (WFC) can be between 2.5 and 3.5 inches. In some embodiments, the face center width (WFC) can be between 2.5 and 2.6 inches, between 2.6 and 2.7 inches, between 2.7 and 2.8 inches, between 2.8 and 2.9 inches, between 2.9 and 3.0 inches, between 3.0 and 3.1 inches, between 3.1 and 3.2 inches, between 3.2 and 3.3 inches, between 3.3 and 3.4 inches, or between 3.4 and 3.5 inches. The face center width (WFC) can be primarily influenced by the curvature of the strike face perimeter 205 proximate the toe end 208.2. Hosel Geometry

[0147] As discussed above, some embodiments of golf club heads according to the present disclosure have a weight system that eliminates the need for a “tip weight” in the hosel, which enables a shorter hosel and increases discretionary mass. Eliminating the tip weight reduces mass proximate the heel end 212, increases MOI, and improves sound (as will be discussed in greater detail below).

[0148] Referring to FIGS. 24 and 25, the club head body 204 comprises a hosel 210 proximate the heel end 212 and configured to receive a shaft. The hosel 210 comprises a hosel bore 150 defined by a hosel bore wall 258 extending downward along the hosel axis 2055 from an upper hosel ledge 251. The hosel 210 further comprises a hosel bore tip 255 defining a base of the hosel bore 250. The hosel 210 defines a hosel axis 2055 extending through a geometric center of the upper hosel ledge 251 and a geometric center of the hosel bore tip 255. The hosel 210 further defines a hosel bore height (HBH) measured between the upper hosel ledge 251 and the hosel bore tip 255 along the hosel axis 2055.

[0149] As discussed above, traditional club heads 400 typically comprise an extended hosel 410 which can accommodate a “tip weight.” In order to accommodate a “tip weight” traditional club heads 400 generally have a greater hosel bore height (HBH), as shown in FIG. 25. Traditional golf club heads, such as the one shown in FIG. 25 typically have a hosel bore height between 1.0 inch and 1.5 inches.

[0150] Removing R the “tip weight” allows the hosel 410 to be shortened. Golf club heads constructed according to the present disclosure can have a hosel 210 with a hosel bore height (HBH) between 0.675 inches and 1.250 inches, as shown in FIG. 24. In some embodiments, the hosel 210 can have a hosel bore height (HBH) between 0.675 and 0.725 inch, between 0.725 and 0.775 inch, between 0.775 and 0.825 inch, between 0.825 and 0.875 inch, between 0.875 and 0.925 inch, between 0.925 and 0.975 inch, between 0.975 inch and 1.025 inches, between 1.025 and 1.075 inches, between 1.075 and 1.125 inches, between 1.125 and 1.175 inches, between 1.175 and 1.225 inches, or between 1.225 and 1.250 inches. Traditional club heads can have a hosel bore height between 1.5 inches and 2.0 inches. Therefore, golf club heads constructed according to the present disclosure can have a hosel bore height (HBH) which is 16.67% to 66.25% shorter than traditional golf club heads.

[0151] Additionally, the aforementioned hosel geometries (hosel height, hosel length, and hosel bore height) enable the club head frequency ranges, discussed below. These golf club frequencies determine the golf club head sound (or acoustic) profile. Though inherently subjective, certain club head acoustic characteristics, described below, are regarded as favorable. Moreover, these favorable sound characteristics can be achieved by adjusting an overall length of the hosel. The overall hosel length is measured from the distal end 154 (or hosel bore distal end 154) to the ground plane 160 along the hosel axis 1055. In some embodiments, the overall hosel length ranges inclusively between 0.75 inches and 3.0 inches. In some embodiments, the overall hosel length ranges inclusively between 1.0 inches and 2.5 inches. In some embodiments, the overall hosel length can range between 0.75 inch and 1.0 inch, 1.0 inch and 1.25 inches, 1.25 inches and 1.50 inches, 1.50 inches and 1.75 inches, 1.75 inches and 2.0 inches, 2.0 inches and 2.25 inches, 2.25 inches and 2.50 inches, 2.50 inches and 2.75 inches, or 2.75 inches and 3.0 inches. In one exemplary embodiment, the overall hosel length is between 2.40 inches and 2.73 inches.

[0152] Hosel height (HH), hosel length (HL), and hosel bore height (HBH) can also influence the overall hosel length, thereby altering the club head frequency, as discussed in Example VII. In other words, the club head frequency, influenced by overall hosel length, can quantitatively describe the club head sound profile.

[0153] Golf club heads constructed according to the present disclosure are particularly categorized by the club head frequencies at the 9th and 10th modes. Moreover, the threshold frequencies, or minimum frequency levels, are analyzed in view of the particular club head type. Specifically, game improvement club heads and player-style club heads may comprise different threshold frequencies. Game improvement club heads generally feature a larger size, greater perimeter weighting, and more club head offset than player-style club heads, which tend to have a more compact size, blade-like shape, and less offset. Due to the size and shaping differences between the game improvement club heads and the player-style club heads, the desired frequency ranges between the two club heads vary.

[0154] Particularly, in one embodiment, generally relevant to a game improvement club head, the club head frequency can be greater than or equal to 4000 Hz at mode 9 and greater than or equal to 6000 Hz at mode 10. Preferably, the club head frequency can be greater than or equal to 4300 Hz at mode 9 and greater than or equal to 6300 Hz at mode 10. More preferably, the club head frequency can be greater than or equal to 4800 Hz at mode 9 and greater than or equal to 6700 Hz at mode 10. In another embodiment, generally relevant to a player-style club head, the club head frequency can be greater than or equal to 6000 Hz at mode 9 and greater than or equal to 8000 Hz at mode 10. More preferably, the club head frequency can be greater than or equal to 6300 Hz at mode 9 and greater than or equal to 8500 Hz at mode 10.III. Weight System

[0155] According to certain aspects of the present disclosure, a weight system is incorporated into an insert coupled to the club head, thereby to facilitate swing weighting of the club head. Unlike conventional club heads, club heads constructed according to this embodiment omit a “tip weight.” Described herein are various embodiments of an iron-type golf club head with high forgiveness, increased ball speed, and high launch. The iron-type golf club heads disclosed herein can comprise an interior cavity. Further, the iron-type golf club heads disclosed herein can comprise an insert which further comprises a weight system. The insert at least partially fills the interior cavity and accommodates one or more weight members to provide a weight system for swing weighting. The insert can comprise a coverage volume greater than 40% of an available volume of the interior cavity. The insert visually fills the cavity, creating the appearance of a hollow-body or capped-back club head. To enhance this hollow-body or capped-back look, the rear surface of the insert may be designed to complement the geometry of the club head rear.1. Interior Cavity

[0156] Referring to FIGS. 16-27, the club head defines an interior cavity. The rear 218 can extend only partially between the sole 215 and the top rail 214, forming an interior cavity 275 that fluidly communicates with the club head exterior. In many embodiments, the interior cavity 275 is bounded by the strike face rear surface 223, interior cavity base 276, interior cavity top 277, and interior cavity opening perimeter 329, or a combination thereof (see, for example FIG. 23). As illustrated in FIG. 22, the interior cavity 275 comprises an interior cavity opening perimeter 129. The interior cavity opening perimeter 129 provides access to the interior cavity 275 from the exterior of the club head and allows the club head body 204 to receive an insert 265, as discussed in further detail below.

[0157] The size and shape of the interior cavity 275 is at least partially defined by the shape of the strike face rear surface 223. As discussed above and illustrated in FIG. 23, the sole 215 extends upward from a sole exterior surface 219 at least partially towards the top rail 214. The sole 215 does not extend all the way to the top rail 214 and does not contact the top rail 214. Rather, the interior cavity opening perimeter 129 defines an opening into the interior cavity 175 such that at least a portion of the strike face rear surface 223 is exposed.2. Insert

[0158] In many embodiments, the iron-type golf club head comprises an insert 265 located within the interior cavity 275. The insert 265 comprises an insert front surface 266, an insert rear surface 267 opposite the insert front surface 266, and an insert perimeter wall 268. The insert 265 can be positioned within the interior cavity 275 and can be secured to and / or contact the strike face rear surface 223. Specifically, the insert rear surface 267 can be configured to be adhered, or otherwise mechanically coupled, directly to strike face rear surface 223. In many embodiments, the strike face rear surface 223 receives an adhesive member 247 which is coupled to the strike face rear surface 223. The adhesive member 247 then receives the insert 265 and secures the insert to the club head 200.

[0159] The insert 265 can have an insert thickness 269 which is measured between an insert front surface 266 and insert rear surface 267 in a direction perpendicular to the loft plane 1022. In some embodiments, the insert thickness 269 can vary in a top rail 214 to sole 215 direction and / or a heel end 212 to toe end 208 direction. An insert 265 with a varying insert thickness 269 can be designed such that thicker regions are positioned at frequent impact locations. Reinforcing frequent impact locations can enable the strike face 220 to have a corresponding decreased strike face thickness 140, thereby increasing face deflection at frequent impact locations and increasing ball speed without sacrificing durability. The insert 265 can be positioned within the interior cavity 275 such that the insert rear surface 267 is visible when looking at the club head from the rear. The insert rear surface 267 can further span or extend across at least a portion of the strike face rear surface 223 in a heel end 212 to toe end 208 direction.

[0160] In some embodiments, the insert can comprise an insert thickness 269 which is less than 1.0 inch. In other embodiments, the insert can comprise an insert thickness which is between 0.10 inch and 0.30 inch, 0.30 inch and 0.50 inch, 0.50 inch and 0.70 inch, 0.70 inch and 0, 90 inch, 0.90 inch and 1.10 inches, 1.10 inches and 1.30 inches, or between 1.30 inches and 1.50 inches.

[0161] The insert 265 at least partially fills the interior cavity 275. In many embodiments, the insert 265 substantially fills the entire volume of the interior cavity 275. In such embodiments, the insert 265 is complementarily shaped to the geometry of the interior cavity and the rear surface of the insert 265 is substantially flush with the interior cavity opening perimeter 229. In other embodiments, such as the embodiment illustrated in FIG. 23, the insert 265 may only partially fill the volume of the interior cavity, such that the insert rear surface is recessed within the interior cavity. In many embodiments, the insert 265 can fill between 40% and 100% of the volume of the interior cavity 275. In many embodiments, the insert 265 can fill a range varying inclusively between 40% and 45%, 45% and 50%, 50% and 55%, 55% and 60%, 60% and 65%, 65% and 70%, 70% and 75%, 75% and 80%, 80% and 85%, 85% and 90%, 90% and 95%, or between 95% and 100% of the volume of the interior cavity 275. In some embodiments, the insert 265 can fill approximately 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100% of the volume of the interior cavity 275. In some embodiments, the insert 265 can fill between 40% and 50%, 50% and 60%, 60% and 75%, 75% and 85%, 85% and 95%, 80% and 90%, 75% and 90%, or between 85% and 100% of the volume of the interior cavity 275.

[0162] Additionally, the insert 265 can have an insert rear surface 267 with a surface area of the insert rear surface which is approximately equal to the surface area of the strike face rear surface 223. A ratio between the surface area of the insert rear surface 267 and the surface area of the strike face rear surface 223 (hereafter “insert surface area ratio”) can be between 0.700 and 1.200. In some embodiments, the insert surface area ratio can be between 0.700 and 0.725, 0.725 and 0.750, 0.750 and 0.800, 0.800 and 0.850, 0.850 and 0.900, 0.900 and 0.950, 0.950 and 1.000, 1.000 and 1.050, 1.050 and 1.100, or between 1.100 and 1.200. In other embodiments the insert surface area ratio can be greater than 0.600, greater than 0.700, greater than 0.800, greater than 0.900, greater than 1.000, greater than 1.100, or greater than 1.200.

[0163] The insert 265 can be formed from a polymer or flexible material with a low shore durometer (i.e., soft material). The insert 265 can be formed from a polymer matrix. The polymeric matrix can comprise glass-filled elastomer, a stainless steel-filled elastomer, a tungsten-filled elastomer, a thermoplastic polyurethane (TPU) composite, a thermoplastic elastomer (TPE) composite, or any other elastomer matrix composite, a Kevlar® (aramid) fiber-reinforced polymer, a carbon-fiber reinforced polymer, rubber, ethylene-vinyl acetate foam, polymer-based foam, any combination of a suitable resin and a suitable reinforcing fiber, or any combination of the above materials. Soft or flexible insert materials can improve the feel and sound of the golf club head through impact.

[0164] In some embodiments, the insert 265 can be shaped to complement the geometry of the rear 218. As discussed above, the insert front surface 266 can be shaped to give the appearance of being flush with the rear 218, providing the appearance that the insert 265 encloses the interior cavity. However, the insert 265 is dimensioned such that there is fluid communication between the interior cavity 275 and the exterior surface 180 of the club head 200. In particular, there is a gap between the insert perimeter wall 268 and the interior cavity opening perimeter 229. As shown in FIG. 36B, a gap width (WG) is measured between the insert perimeter wall 268 and the interior cavity opening perimeter 229 in a direction perpendicular to the Z-Axis 1060. The gap width (WG) can vary about the interior cavity opening perimeter 229.

[0165] In some embodiments the insert 365 can further comprise a plurality of recesses 230 on the insert rear surface 367. The plurality of recesses on the insert rear surface 367 can aide with adhesion of the insert rear surface 367 to the strike face rear surface 323. Additionally, the plurality of recesses on the insert rear surface 367 can decrease the mass of the insert 365, freeing up club head 300 mass which can be utilized elsewhere.

[0166] In some embodiments, the club head 200 can have a variable gap width (WG) which varies between 0.01 inch and 0.05 inch about the interior cavity opening perimeter 229. In other embodiments, the club head 200 can have a variable gap width (WG) about the interior cavity opening perimeter 229 which is between 0.005 and 0.025 inch, 0.025 inch and 0.075 inch, 0.075 inch and 0.125 inch, 0.010 and 0.025 inch, 0.020 and 0.080 inch, 0.035 and 0.075 inch, 0.010 and 0.100 inch, or between 0.025 and 0.060 inch.

[0167] In other embodiments, the club head 200 can have a constant gap width (WG) which is constant about the interior cavity opening perimeter 229. In some embodiments, the gap width (WG) can a constant value about the interior cavity opening perimeter 229 which is less than 0.0010 inch, 0.0015 inch, 0.0020 inch, 0.0025 inch, 0.0030 inch, 0.0035 inch, 0.0040 inch, 0.0045 inch, 0.0050 inch, 0.0055 inch, 0.0060 inch, 0.0065 inch, 0.0070 inch, 0.0075 inch, 0.0080 inch, 0.0085 inch, 0.0090 inch, 0.0095 inch, 0.0100 inch, 0.0105 inch, 0.0110 inch, 0.0115 inch, 0.0120 inch, 0.0125 inch, 0.0130 inch, 0.0135 inch, 0.0140 inch, 0.0145 inch, 0.0150 inch, 0.0155 inch, 0.0160 inch, 0.0165 inch, 0.0170 inch, 0.0175 inch, 0.0180 inch, 0.0185 inch, 0.0190 inch, 0.0195 inch, 0.0200 inch, 0.0205 inch, 0.0210 inch, 0.0215 inch, 0.0220 inch, 0.0225 inch, 0.0230 inch, 0.0235 inch, 0.0240 inch, 0.0245 inch, or less than 0.0250 inch. In some embodiments, the gap width (WG) can a constant value about the interior cavity opening perimeter 229 which is greater than 0.0010 inch, 0.0015 inch, 0.0020 inch, 0.0025 inch, 0.0030 inch, 0.0035 inch, 0.0040 inch, 0.0045 inch, 0.0050 inch, 0.0055 inch, 0.0060 inch, 0.0065 inch, 0.0070 inch, 0.0075 inch, 0.0080 inch, 0.0085 inch, 0.0090 inch, 0.0095 inch, 0.0100 inch, 0.0105 inch, 0.0110 inch, 0.0115 inch, 0.0120 inch, 0.0125 inch, 0.0130 inch, 0.0135 inch, 0.0140 inch, 0.0145 inch, 0.0150 inch, 0.0155 inch, 0.0160 inch, 0.0165 inch, 0.0170 inch, 0.0175 inch, 0.0180 inch, 0.0185 inch, 0.0190 inch, 0.0195 inch, 0.0200 inch, 0.0205 inch, 0.0210 inch, 0.0215 inch, 0.0220 inch, 0.0225 inch, 0.0230 inch, 0.0235 inch, 0.0240 inch, 0.0245 inch, or greater than 0.0250 inch.3. Weight Members

[0168] In many embodiments, such as the embodiment illustrated by FIG. 20, the insert 265 can comprise a plurality of weight members 270. In one embodiment, such as the embodiment illustrated in FIG. 20, the insert 265 comprises a first weight member 271 and a second weight member 272. In other embodiments, the plurality of weight members 270 can comprise only a first weight member 271. Further, the plurality of weight members 270 can be located at any portion(s) of the insert 265. In a preferred embodiment, the weight members can be located in the insert 265 at locations proximate the strike face perimeter 205. One exemplary embodiment, shown in FIG. 20, comprises a first weight member 271 proximal the toe end 208 and the sole 215 and a second weight member 272 proximate the toe end 208 and the top rail 214.

[0169] In many embodiments, the plurality of weight members 270 may be configured to be attached to a plurality of apertures 285 located on the insert front surface 266. In some embodiments, the plurality of weight members 270 are removably coupled to the insert 265, such as by mating threads in the weight members 270 and the plurality of apertures 285 of the insert 265. In other embodiments, the plurality of weight members 270 can be permanently or semi-permanently affixed to the plurality of apertures 285 of the insert 265. In particular, the plurality of weight members 270 can be attached to the insert 265 through any suitable means such as: usage of a snap-fit mechanism, interlocking methods, adhesives, or other means of mechanical coupling.

[0170] In many embodiments, each weight member of the plurality of weight members 270 can be shaped to sit flush with the insert rear surface 267 when residing within an aperture of the plurality of apertures 285. For example, the first weight member 271 can be shaped to sit flush within a first aperture 236 and the second weight member 272 can be shaped to sit flush within a second aperture 237.

[0171] Each weight member of the plurality of weight members 270 can be interchangeable with a group of weight members having a similar size and shape, but varying in mass. The ability to interchange removable weight members allows for easy swing weight adjustment. For example, a plurality of weight members may include a first weight member which is chosen from a group of first weight members of varying mass and a second weight member which is selected from a group of second weight members of varying mass. In another example a plurality of weight members may include a first weight member with a predetermined mass (hereafter a “fixed mass weight member”) and a second weight member selected from a group of second weight members having a varying mass (hereafter a “variable mass weight member”). In some embodiments, one or more of the apertures 285 do not receive a weight member 220.

[0172] The plurality of weight members can comprise a high-density material with a density greater than that of the club head body. In many embodiments, the plurality of weight members can be formed of tungsten or a tungsten alloy such as a tungsten-nickel alloy, tungsten-carbide alloy, tungsten-iron alloy, or a similar suitable material. In many embodiments, the plurality of weight members can be formed of a material which has a specific gravity ranging between 10 and 30. The plurality of weight members can be formed of a material which has a specific gravity between 10 and 12, 12 and 14, 14 and 16, 16 and 18, 18 and 20, 20 and 22, 22 and 24, 24 and 26, 26 and 28, or 28 and 30. For example, the plurality of weight members can have a specific gravity of 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30.

[0173] To allow for adequate adjustability of swing weight it is important that there is a significant variation in mass between 1) a plurality of weight members wherein each weight member is selected from a group of weight members to be the weight members with the lowest mass (hereafter “the lightest weight member build mass” or “lightest WMBM”) and 2) a plurality of weight members wherein each weight member is selected from a group of weight members to be the weight members with the greatest mass (hereafter “the heaviest weight member build mass” or “heaviest WMBM”). In general, a difference of 10 grams between the lightest weight member build mass and heaviest weight member build mass is sufficient to allow for adjustability of swing weight. In some embodiments the difference in mass between the lightest WMBM and heaviest WMBM (hereafter “build mass adjustability”) can be between 8 grams and 30 grams. The plurality of weight members described herein can allow for a build mass adjustability of between 8 and 10, 10 and 12, 12 and 14, 14 and 16, 16 and 20, 20 and 24, 24 and 26, 26 and 28, or 28 and 30 grams.

[0174] A sufficient build mass adjustability can be accomplished without the need for each weight member of the plurality of weight members to be a variable mass weight member. For example, a plurality of weight members comprising a first weight member selected from a group of first weight members having a mass of 5-15 grams and a second weight member which always has a mass of 2 grams provides for 10 grams of build mass adjustability. There are situations where including fixed mass weight members is advantageous for tuning key performance characteristics, as described below.

[0175] Key performance characteristics can be selectively tuned by including fixed mass weight members in the plurality of weight members. Cavity-back irons are designed for golfers who typically struggle to achieve a high enough launch angle at impact. This typically includes golfers with “slow” swing speeds (i.e. a 7-iron swing speed of less than 70 mph). To solve this problem, it is generally desirous to lower the club head CG to thereby increase launch angle. A first exemplary club head incorporating fixed mass weight members can be constructed to 1) lower CG across all club head build masses, 2) increase MOI and thereby increase forgiveness, and 3) provide adequate build mass adjustability for swing weighting.

[0176] The first exemplary club head can comprise a plurality of weight members including a first weight member located proximate the sole and a second weight member located proximate the top rail and the toe end. The first weight member can be a fixed mass weight member having a large mass. The second weight member can be a variable weight member wherein every second weight member of the group of second weight members has a mass less than that of the first weight member. The first weight member of the first exemplary club head can place a large amount of mass near the sole thereby lowering CG while increasing MOI of the club head. The second weight member of the first exemplary club head can place a relatively small amount of mass near the top rail, thereby minimizing the CG height contribution of the second weight member. Furthermore, placing the second weight member near the top rail can aid in increasing perimeter weighting of the club head, thereby increasing club head MOI. Accordingly, the first exemplary club head is that the lightest WMBM will have the lowest CG height and the CG height will increase as build mass increases. This correlation is advantageous since low swing speed golfers tend to struggle the most with low launch angle and also tend to require the lightest WMBM. Thereby, the first exemplary club head is an illustrative example of how key performance characteristics can be selectively tuned using the adjustable mass insert of the present invention.

[0177] In another exemplary embodiment, a club head 500 comprises a shortened hosel bore and a weighted badge to produce a low center of gravity and increase club head MOI to improve launch and spin characteristics, as illustrated in FIGS. 47-49. The weighted badge also enables swing-weighting of the club head to fit different golfers swings. The badge further reduces vibrational response in the club head by contacting the rear surface of the strike face and a top surface of the sole bar to improve sound at impact. In this embodiment, the club head further comprises a locating feature to improve badge alignment and retention.

[0178] As illustrated in FIGS. 47-49, the club head 500 comprises a strike face, a toe end 508, a heel end 512, a hosel 510, a top rail 514, a sole 515, a rear cavity 518, and a badge 565 having a weight 570. The hosel 510 has a shortened hosel bore, as described above, that lowers the center of gravity while still providing loft and lie adjustability. The club head 500 further comprises a sole bar 580 having a sole bar top surface 581, a sole bar heel surface 582, and a sole bar toe surface 583. The sole bar top surface 581 has a locating feature 590 that improves badge alignment and retention. In this embodiment, the locating feature 590 is an elongated recess with rounded ends forming a blind hole in the sole bar top surface 581. In other embodiments, such as in a club head 600 illustrated in FIG. 50, the locating features 690 are at least two circular bores. In other embodiments, the locating features 590, 690 can have any size, shape, or number to increase badge alignment and retention as needed.

[0179] In the illustrated embodiment in FIG. 49, the badge 565 is coupled to the club head 500 by an adhesive member 547. The adhesive member 547 contacts the sole bar top surface 581 and the strike face rear surface to increase badge retention and dampen vibrations. The badge 565 contacts the strike face rear surface above the adhesive member 547.

[0180] The badge 565 comprises complementary geometry to the locating feature 590. In this embodiment, the badge 565 comprises a protrusion 591 located on the bottom of the badge that is shaped similarly to the locating feature 590. The protrusion 591 fits within and is surrounded by the locating feature 590. The protrusion 591 cannot be seen from an exterior view of the club head.

[0181] The badge 565 has a volume between 1.0 and 6.0 cc. For example, the badge 565 can have a volume between 1.0 and 4.0 ccs, 2.0 and 5.0 ccs, or between 3.0 and 6.0 ccs. In some embodiments, the badge has a volume of about 1.0 cc, 1.5 ccs, 2.0 ccs, 2.5 ccs, 3.0 ccs, 3.5 ccs, 4.0 ccs, 4.5 ccs, 5.0 ccs, 5.5 ccs, or 6.0 ccs.

[0182] The badge 565 has a length, measured from a heel most point to a toe most point between 1.75 and 3.0 inches. For example, the badge 565 can have length between 1.75 inches and 3.0 inches, each 0.5 inches wide, are: 1.75 and 2.25 inches, 2.00 and 2.50 inches, 2.25 and 2.75 inches, or between 2.50 and 3.00 inches.

[0183] The badge 565 has a height, measured from a topmost point to a bottom most point between 0.350 and 0.525 inches. For example, the badge 565 can have a height between 0.350 and 0.400 inches, 0.375 and 0.425 inches, 0.400 and 0.450 inches, 0.425 and 0.475 inches, 0.450 and 0.500 inches, or between 0.475 and 0.525 inches.

[0184] The badge 565 has a depth, measured from a front to back direction between 0.45 and 0.70 inch. For example, the badge 565 can have a depth between 0.450 and 0.500 inches, 0.475 and 0.525 inches, 0.500 and 0.550 inches, 0.525 and 0.575 inches, 0.550 and 0.600 inches, 0.575 and 0.625 inches, 0.600 and 0.650 inches, 0.625 and 0.675 inches, or between 0.650 and 0.700 inches.

[0185] The badge 565 has a badge top surface 566 and a badge rear surface 567 to form the exterior, or visible, surfaces of the badge 565. In some embodiments, the badge rear surface 567 can be continuous with a sole bar rear surface. In other embodiments, the badge rear surface 567 can be offset inwardly from the sole bar rear face. The badge 567 further comprises angled ends in the heel and toe that are complementary to the sole bar heel surface 582 and the sole bar toe surface 583. The badge top surface 566 and the badge rear surface 567 are planar to improve the overall aesthetic of the club head. In other embodiments, the badge 567 can have non-planar surfaces, or other number of exterior surfaces to achieve a desired aesthetic. In the illustrated embodiment, the weight 570 is positioned within the badge top surface 566.

[0186] In other embodiments, the weight 570 may be positioned in other location on the badge such as the badge rear surface 567, or on the badge bottom surface. The badge weight 570 comprises a badge weight density that is greater than a badge density. The higher density of the badge weight allows the badge 565 to be used for swing weighting purposes during club head assembly.

[0187] The badge weight 570 can have a mass between 0.5 grams and 10 grams. For example, the badge weight 570 can have a mass between 0.5 and 1.0 grams, 1.0 and 1.5 grams, 1.5 and 2.0 grams, 2.0 and 2.5 grams, 2.5 and 3.0 grams, 3.0 and 3.5 grams, 3.5 and 4.0 grams, 4.0 and 4.5 grams, 4.5 and 5.0 grams, 5.0 and 5.5 grams, 5.5 and 6.0 grams, 6.0 and 6.5 grams, 6.5 and 7.0 grams, 7.0 and 7.5 grams, 7.5 and 8.0 grams, 8.0 and 8.5 grams, 8.5 and 9.0 grams, 9.0 and 9.5 grams, or between 9.5 and 10.0 grams. In other embodiments, the badge weight 570 can have a mass between 0.5 and 3.5 grams, 2.0 and 5.0 grams, 3.5 and 6.5 grams, 5.0 and 8.0 grams, or between 7.0 and 10.0 grams.

[0188] The badge weight 570 can have a volume between 0.25 cc and 7.5 cc. For example, the badge weight 570 can have a volume between 0.25 and 2.25 ccs, 1.25 and 3.25 ccs, 2.25 and 4.25 ccs, 3.25 and 5.25 ccs, 4.25 and 6.25 ccs, or between 5.0 and 7.0 ccs.

[0189] The badge weight 570 can be adhesively attached, integrally attached such as by co-molding, or mechanically attached to the badge 565. The badge weight 570 can also have other shapes or geometries as desired to achieve a desired mass properties such as lowered center of gravity or higher MOI. For example, in one embodiment, the badge 570 can have two weights positioned on a heel end and toe end of the badge to improve the MOI of the club head while enabling swing-weighting of the club head.

[0190] In another embodiment, a club head 700 can comprise an insert 765 with a weighted cap 770 that is positioned within a rear cavity in the club head to improve badge retention and vibrational response, as illustrated in FIG. 51. In this embodiment, the club head 700 is similar club heads 500 and 600 described above, in that the club head 700 has a lowered hosel bore that is used in combination an insert 765 to lower the center of gravity and increase the MOI of the club head. The club head 700 is different than the embodiments 500 and 600 above in that the club head 700 has a rear cavity that houses the insert instead of having locating features. The rear cavity has a rear cavity front wall 731, a rear cavity bottom wall 732, and a rear cavity rear wall 733 that define the rear cavity. The insert 765 is adhesively attached to the rear cavity front wall 731, the rear cavity bottom wall 732, and the rear cavity rear wall 733. The insert 765 comprises a weighted cap 770 that covers the insert 765. The weighted cap 770 is similar to the badge weight 570 described above in that the weighted cap 770 is used for swing weighting purposes.

[0191] The weighted cap 770 has a mass between 1 and 15 grams. For example, the weighted cap 770 can have a mass between 1.0 and 4.0 grams, 2.5 and 5.5 grams, 4.0 and 7.0 grams, 5.5 and 8.5 grams, 7.0 and 10.0 grams, 8.5 and 11.5 grams, 10.0 and 13.0 grams, 11.5 and 14.5 grams, or between 12.0 and 15.0 grams.4. Additional Features

[0192] The club heads described herein can comprise additional features which complement the weight systems described herein. The additional features described herein can be used in any combination and in conjunction with any of the embodiments described herein.A. Strut

[0193] In some embodiments, such as the embodiment of FIGS. 28-37 the club head body 304 can comprise one or more struts 334. The strut 334 can serve to reinforce the club head body and provides a structure for the insert 365 to abut. For a detailed description of a strut 334, see U.S. Pat. No. 9,517,393, which is incorporated herein by reference. The strut 334 can extend between two non-adjacent portions of the interior cavity opening perimeter 328. In some embodiments, the strut can extend between the interior cavity opening perimeter 328 proximate the top rail 310 and the interior cavity opening perimeter 328 proximate the sole 315. In some embodiments, the strut can extend between the interior cavity opening perimeter 328 proximate the heel end 312 and the interior cavity opening perimeter 328 proximate the toe end 308. The strut 334 may be formed as a bar, beam, channel, or rod. The one or more struts 334 can complement geometry on the insert rear surface 367 to aide in securing the insert 365 to the club head body 301. The strut can have a strut front surface 348 and strut perimeter walls 349 on either side of the strut front surface 348. The strut 334 can define a strut longitudinal axis 3095 extending through a geometric center of the strut and in a direction perpendicular to the Z-axis 3060. The strut longitudinal axis3095 can define a strut angle 1006 defined between the strut longitudinal axis 3095 and the ground plane 360, as shown in FIG. 37. The strut can define a strut width (WS), measured between the strut perimeter walls 349 in a direction perpendicular to the strut longitudinal axis.

[0194] In some embodiments the strut angle 1006 can be between 15 degrees and 165 degrees. In other embodiments the strut angle 1006 can be between 15 degrees and 30 degrees, 30 degrees and 45 degrees, 45 degrees and 60 degrees, 60 degrees and 75 degrees, 75 degrees and 90 degrees, 90 degrees and 105 degrees, 105 degrees and 120 degrees, 120 degrees and 135 degrees, 135 degrees and 150 degrees, or between 150 degrees and 165 degrees.

[0195] In some embodiments, the strut width (WS) can be 0.25 inches. In other embodiments, the strut width (WS) can be between 0.10 inch and 0.60 inch. In other embodiments, the strut width (WS) can be between 0.10 inch and 0.15 inch, 0.15 inch and 0.20 inch, 0.20 inch and 0.25 inch, 0.25 inch and 0.30 inch, 0.30 inch and 0.35 inch, 0.35 inch and 0.40 inch, 0.40 inch and 0.45 inch, or between 0.45 inch and 0.50 inch. In other embodiments the strut width (WS) can be greater than 0.10 inch, 0.15 inch or greater than 0.20 inch. In other embodiments the strut width (WS) can be less than 0.60 inch, 0.55 inch or less than 0.50 inch. The strut width (WS) is a partial determinate of the reinforcement the strut provides and can be selected to control the hinge effect of the club head at impact.

[0196] In some embodiments, the insert 365 can comprise an insert undercut 331 which compliments the geometry of the strut 334. The insert undercut can have an insert undercut width (WIU), measured between the insert undercut perimeter walls 332, which is equal to or less than the strut width (WS). In some embodiments, the insert undercut width (WIU) can be 0.25 inches. In other embodiments, the insert undercut width (WIU) can be between 0.10 inch and 0.15 inch, 0.15 inch and 0.20 inch, 0.20 inch and 0.25 inch, 0.25 inch and 0.30 inch, 0.30 inch and 0.35 inch, 0.35 inch and 0.40 inch, 0.40 inch and 0.45 inch, or between 0.45 inch and 0.50 inch. In other embodiments the insert undercut width (WIU) can be greater than 0.10 inch, 0.15 inch or greater than 0.20 inch. In other embodiments the insert undercut width (WIU) can be less than 0.60 inch, 0.55 inch or less than 0.50 inch.

[0197] To further aide in securing the insert 365, the strut 334 can comprise complementary receiving geometry to the insert 365. In some embodiments, the insert 365 can comprise posts or pegs which are received by corresponding through-holes on the strut 334. In other embodiments the strut 334 and the insert 365 can both comprise through-holes which receive a separately formed screw, peg, post, or similar securing apparatus for securing the strut 334 to the insert 365.B. Mass Pads

[0198] In some embodiments, the club head can comprise a mass pad formed as an integral part of the club head body. In other embodiments, all or a portion of the mass pad can be separately formed and attached to the sole. The weight members disclosed herein may comprise a similar or different material than the body material. In some embodiments, the mass pad can comprise a higher density material than the body material to concentrate mass in a desired location. The club head 300 can form a mass pad 385 located in a low and rearward portion of the interior cavity 375, proximate both the sole 315 and the rear 318. The mass pad 385 comprises a mass pad front surface 359 disposed toward the strike face 320 but spaced rearward from the strike face rear surface 323, such that the mass pad front surface 359 does not contact the strike face 320.

[0199] The mass pad 385 can define a mass pad depth (DMP). The mass pad depth (DMP) assists in dictating club head CG and mass properties. The mass pad 385 defines a mass pad depth (DMP) measured between the strike face rear surface 323 and the mass pad front surface 259. In some embodiments, the mass pad depth (DMP) is variable. In such embodiments, the mass pad depth (DMP) is smallest proximate the sole and increases in a top-rail direction. This configuration creates a mass buildup soleward from Face center (FC), causing the club head CG to be lower. Lowering the CG improves ball speeds and launch characteristics. In other embodiments, the mass pad depth (DMP) can be substantially constant.I. EXAMPLESExample I—Comparison of Mass Properties Between One Embodiment of Club Head Described Herein And Control Club Head

[0200] Example I provides a comparison between two embodiments of a traditional iron-type golf club head with typical hosel bore geometry and length, one having an external notch and the other with no notch, and a separate embodiment of a club head with the hosel bore geometry described herein with no external notch. More specifically, Example 1 discusses differences in CG and MOI between two traditional club heads and one embodiment of the club head with the low hosel geometry described above, as shown in Table 1.

[0201] As shown in FIG. 6A, the two traditional iron-type golf club head comprising a typical hosel geometry and a hosel notch (hereafter referred to as “Control Club Head 1” and “Control Club Head 2”). Also described herein is an exemplary embodiment having an iron-type golf club head without a notch, a shorter hosel bore geometry and wall tapering as described above. Control Club Head 1 comprises the same external structure as Exemplary Club Head 1.

[0202] Control Club Head 1 and Exemplary Club Head 1 comprise similar body structure, volume, and loft angle. A direct comparison highlighting differences in hosel dimensions, CG, MOI, and club head mass can be seen below in Table 1.TABLE IClub Head Dimensions in Control Heads 1 & 2 vs. Exemplary Club Head Control Club Control Club Exemplary Head 1 Head 2 Club Head 1Club head mass (g) 255 260 255 Total hosel volume 0.172 0.135 0.190 (in3)Hosel volume above 0.172 0.135 0.171 midplane (in3) Hosel volume above 0.172 0.135 0.150 hosel-body meeting point (in3) Ground plane to 0.896 0.917 0.896 hosel-body meeting point (in) Ground plane to 0.706 0.695 0.706 midline axis (in) Ground plane to 0.927 1.137 0.397 bottom of hosel bore (in)Ground plane to top 2.335 2.340 2.135 of hosel (in) CGx (in) 0.082 −0.002 −0.025 Cgy (in) 0.524 0.538 0.486 MOIxx (g / in2) 98.5 83.5 89.4 MOIyy (g / in2) 374.7 321.4 356.1 MOIzz (g / in2) 429.1 367.3 403.1 Inner bore diameter 0.355 0.353 0.153 at bottom hosel (in) Inner bore diameter 0.408 0.408 0.408 at top hosel (in) Outer hosel diameter 0.540 0.520 0.540 at top hosel (in) Wall thickness 0.077 0.0568 0.077 (range if applicable) average at mid hosel cross section (in) Wall thickness 0.066 0.052 0.066 (range if applicable) constant average constant at upper hosel cross section (in)

[0203] As shown in Table 1, the club head body of Exemplary Club Head 1 is very similar to the bodies of Control Club Head 1 and Control Club Head 2. A distance between the ground plane and a point where the external hosel meets the top rail is the same between Exemplary Club Head 1 and Control Club Head 1, and similar in Control Club Head 2. Additionally, a distance between the ground plane and the mid-line axis is the same between Exemplary Club Head 1 and Control Club Head 1, and similar in Control Club Head 2. Furthermore, hosel wall thicknesses in both an upper region and a middle region of the hosel are the same between Exemplary Club Head 1 and Control Club Head 1 and are similar in Control Club Head 2.

[0204] Table I shows that Exemplary Club Head 1 comprises a hosel bore volume that is 10.5% greater than that of Control Club Head 1, and 40.7% greater than that of Control Club Head 2. An increase in hosel bore volume correlates with an increased extension of the hosel bore into the club head body, thereby creating discretionary weight and lowering the club head center of gravity. Moreover, the entirety of the hosel bore volume for both Control Club Head 1 and Control Club Head 2 are located above the midline axis, while only 90% of the hosel bore volume of Exemplary Club Head 1 is positioned above the midline axis, with the surplus volume extending below the midline axis and further into the club head. The hosel bore volume positioned below the midline axis further highlights a deeper hosel bore design, which in turn enhances club head CG and mass properties.

[0205] While the hosel bore volume of Exemplary Club Head 1 (0.190 in.3) is greater than both Control Club Head 1 (0.172 in.3) and Control Club Head 2 (0.135 in.3), the external hosel height of Exemplary Club Head 1 (2.135 in.), from the ground plane, is substantially lower than that of Control Club Head 1 (2.335 in.) and Control Club Head 2 (2.340 in.). Specifically, the external hosel height of Exemplary Club Head 1 is 8.6% lower than the hosel of Control Club Head 1, and 8.8% lower than the hosel of Control Club Head 2.

[0206] A distance between the ground plane and the bottom of the hosel bore is much lower in Exemplary Club Head 1, when compared with Control Club Head 1 and Control Club Head 2. Specifically, the height of the Exemplary Club Head 1 hosel bore lower edge from the ground plane is 57.1% lower than Control Club Head 1 and 65.1% lower than Control Club Head 2. This comparison highlights the extent of lengthening which the hosel bore of Exemplary Club Head 1 exhibits. Specifically, the external hosel of Exemplary Club Head 1 is only 8.6%-8.8% lower than Control Club Head 1 and Control Club Head 2, while the internal hosel bore extends much lower, such that its lower edge is 57.1%-65.1% lower than Control Club Head 1 and Control Club Head 2. As mentioned above, the lengthening or extension of the hosel bore lowers club head CG, thereby improving mass properties and club head performance.

[0207] The extended hosel bore of Exemplary Club Head 1 resulted in less material positioned in the heel side of the club head, which increased discretionary mass for strategic placement elsewhere within the club head. As shown in Table 1, the club head mass of Exemplary Club Head 1 was the same as that of Control Club Head 1, and 5 g less than Control Club Head 2. The mass positioned in the heel side of the club head was reduced in the exemplary club head. It was repositioned elsewhere causing the CG to shift both toward the toe and downward. Exemplary Club Head 1 shows a downward shift in CG of 0.038 inch, when compared with Control Club Head 1, or 0.052 inch, when compared with Control Club Head 2. Exemplary Club Head 1 shows a toeward shift in CG of 0.107 inch, when compared with Control Club Head 1, or 0.023 inch, when compared with Control Club Head 2. Moving the club head CG toward the toe offsets the weight of the hosel, thereby aligning the club head CG with the sweet spot. This mass distribution increases club head forgiveness and improves ball speed and launch angle.

[0208] Applicant further noted that MOI of Exemplary Club Head 1 remained in a range comparable to both Control Club Head 1 and Control Club Head 2. Specifically, Exemplary Club Head 1 showed a decrease in MOI in all three of the x, y, and z directions, relative to Control Club Head 1, and an increase in MOI in all three of the x, y, and z directions, relative to Control Club Head 2. The decrease in MOI relative to Control Club Head 1 results from removing mass in the far heel side of the club head. While a higher MOI is generally desirable, it has been found that player performance can be benefited more by a downward shift in CG than an increase in MOI. Specifically, testing shows that performance characteristics including stat area and accuracy can be maintained or improved by a shift in CG, even in cases where MOI is reduced. Therefore, maintaining MOI, while moving CG lower, results in overall performance benefits.Example II—Comparison of Material Deformation From Bending Between One Embodiment of Club Head Described Herein and Control Club Head

[0209] Example II provides a comparison illustrating the effect of a lowered, or lengthened, hosel bore on ability to bend and development of highly visible surface deformation resulting from stress. Specifically, Example II compares one embodiment of the club head described herein, comprising an extended hosel bore lacking an external notch, and one embodiment of a traditional iron-type golf club head, comprising typical hosel bore geometry having an external notch.

[0210] The standard club (hereafter referred to as the “Control Club Head”) comprised a body having a heel, toe, upper portion, and a lower portion, a hosel, a hosel bore configured to connect the golf club head with a shaft, and a notch located below the hosel on the heel side of the body. The Exemplary club (hereafter referred to as the “Exemplary Club Head”) comprised a bore extending lower into the body and shortened hosel relative to the standard club. The Exemplary Club Head also omitted any notch or cutout feature on the heel or surrounding area. All elements, dimensions, and features were the same throughout both club heads.

[0211] When a club head hosel is forcibly bent following manufacturing, the applied force may produce visible marks at the bend site due to material deformation. The amount of material surface deformation was analyzed and recorded on a qualitative feedback scale between an exemplary club and a standard club. A plurality of clubs were forcibly bent at the hosel to a degree ranging between 2° and 4° from neutral, starting position. If a club head was not able to be bent to the desired degree without visible surface deformation (i.e. stress marks), the head received a “−” score. If the club head was able to be bent to the desired degree without significant surface deformation, the club head received a “+” score. The exemplary club head and the standard club head were both measured in this way for upright and flattened lie adjustments as well as open and closed loft adjustments. Table II below details the degree of bending attempted and resultant surface deformation rating.TABLE IIDegree of bending and resultant demarcation rating in a standard club head vs. an exemplary club head Exemplary club head Standard Club Head Surface Surface Deformation Deformation Club no. Degree bent Rating Degree bent Rating1 3.04 +3.87 −2 5.43 +5.01 −3 −4.65 +−4.23 −4 −5.44 +−5.35 +

[0212] Table II illustrates a sample trial between four Exemplary and Standard Club Heads, comparing degree of bending and resultant deformation ratings. Visible deformation marks or discoloration resulting from the forced bending were assessed using the scale described above. Minor variance in degree bent is due to human error within the bending process and is overall negligible, as the bending of the lie angle on a post-manufactured club head can be imprecise. As shown in Table II, the Exemplary Club Head was able to be bent to a similar degree as the Control Club Head. However, the Control Club Head visibly deformed as a result of bending in three out of four samples tested. The Exemplary Club Head remained visibly unaffected by the applied force, while maintaining the ability to be successfully bent to desirable degrees.Example III—Comparison of FEA Response to Applied Forces at Hosel

[0213] This example provides a qualitative comparison illustrating the effect of a lowered, or lengthened, hosel bore on concentration of stress. Specifically, Example III provides a comparison of stress dispersion based on surface area of one embodiment of the club head described herein, comprising a lowered hosel bore and omitting an external notch, and one embodiment of a traditional iron-type golf club head comprising typical hosel bore geometry and having an external notch.

[0214] Stress values at a site of bending for a standard golf club head were compared to those of an exemplary golf club head. The standard golf club head (hereafter referred to as the “Control Club Head”) comprised a crown, sole, face, rear, hosel, and hosel bore. The exemplary golf club head (hereafter referred to as the “Exemplary Club Head”) comprised similar features with a shortened hosel and lowered hosel bore compared to the standard club. With the exception of the hosel, hosel bore, and notch, all dimensions and features between the golf club heads were the same throughout the golf club body.

[0215] Analysis of each club head's response to constant applied bending forces is shown in FIGS. 5B-5D (Exemplary Club Head) and 6B-6D (Control Club Head). Illustrated stresses along the hosel indicate the occurrence of bending in response to the forces applied. In the referenced figures, high amounts of stress are denoted by red coloration, while low amounts of stress are denoted by dark blue coloration. Colors ranging from red to dark blue, such as orange, yellow, green, and light blue denote decreasing amounts of stress in this respective order. The scale of stress in FIGS. 5B-5D and in 6B-6D is equal across both models (i.e., the value of stress in a red area illustrated in FIG. 5B is of equal value to a red area illustrated in FIG. 6B). The colors within these figures illustrate the distribution of stresses across the hosel in both club heads analysed at comparable values.

[0216] It is beneficial for the stressed to be dispersed across the hosel, rather than concentrated at any given site. Areas with higher stress than the surrounding region will often produce visible material surface deformation on the hosel. A club head with high stress across the hosel, but not at any discernably concentrated site, will typically bend without generating such stress marks. This is preferred, as visible surface deformation is not only unsightly, but can also compromise the structural integrity of the hosel at that site.

[0217] As illustrated in FIGS. 5B-5D, the Exemplary Club Head comprising a hosel bore closer to the ground plan than the control club (i.e. low hosel bore) exhibited a similar maximum stress (indicated by a red color) throughout the hosel as the Control Club Head lacking a low hosel bore. Additionally, as shown in FIGS. 5B-5D, the Exemplary Club Head exhibited stresses throughout hosel that lacked any relatively isolated area of high stress when compared to the Control Club Head. The Control Club Head exhibited a concentrated area of stress across the lower end of the hosel, as depicted in FIGS. 6B-6D. This region of concentrated stress indicates the Control Club Head would likely deform along that site if the modeled forces were physically applied to the Control Club Head, such as in post-manufacture bending.

[0218] As stated, the Exemplary Club Head comprising a low hosel bore did not display any highly isolated areas of high stress. Although the maximum stress experienced by both clubs was approximately the same, the Exemplary Club Head exhibited increased stress distribution across the hosel than the Control Club Head. The Exemplary Club Head distributes stress over a larger area, thereby reducing the likelihood of failure or visible stress marks.

[0219] The Exemplary Club Head comprised a lowered hosel bore and shortened hosel compared to the standard club head. All other components of the clubs were the same throughout. The Exemplary Club Head displayed a dispersed stress at the hosel, while the standard club head displayed a line of concentrated stress at a lower portion of the hosel. In conclusion, the shortened hosel and lowered hosel bore reduce the concentration of stress in the lower portion of the hosel and better disperses the stress throughout the entire hosel. This indicates the Exemplary Club Head is able to be bent without a high level of material surface deformation when compared to the Control Club Head lacking a shorted hosel and lowered hosel bore.Example IV—Comparison of Stress Dispersion Between Two Embodiments of the Club Head Described Herein and A Control Club Head

[0220] Example IV provides a qualitative comparison illustrating the effect of a lowered, or deeper, hosel bore on concentration of stress. Specifically, Example IV provides a comparison of stress dispersion based on surface area of two embodiments of the club head described herein, each comprising a lowered hosel bore and lacking an external notch, and one embodiment of a traditional iron-type golf club head comprising typical hosel bore geometry and also a second control lacking an external notch.

[0221] Exemplary Club Head 1 comprises a deeper hosel bore that extends further into the club head than that of the Control Club Head. The hosel bore of Exemplary Club Head 1 terminates along a plane aligned with a heel-most edge of the strike face. Exemplary Club Head 2 comprises a deeper hosel bore that extends further into the club head than that of the Control Club Head and Exemplary Club Head 1. The hosel bore of Exemplary Club Head 2 continues into the club head such that the entire club head is hollowed out and defines a continuous, single void that includes both a body cavity and the hosel bore. The hosel bore walls of the Control Club Head, Exemplary Club Head 1, and Exemplary Club Head 2 comprise a constant thickness that is the same among all three club heads.

[0222] Analysis of each club head's response to constant applied bending forces is shown in FIG. 13 (Control Club Head), FIG. 14 (Exemplary Club Head 1), and FIG. 15 (Exemplary Club Head 2). Illustrated stresses along the hosel indicate the occurrence of bending in response to the forces applied. Referring to FIGS. 13-15, the Control Club Head experienced greater stress per surface area than each of Exemplary Club Head 1 and Exemplary Club Head 2. As such, the Control Club Head experience a higher stress concentration than either Exemplary Club Head. Alternatively, Exemplary Club Head 1 and Exemplary Club Head 2 experience less concentrated and more dispersed stresses than Control Club Head 1 when the same amount of force is applied. As the surface area of the bore increases, bending stresses become less concentrated, dispersing more evenly across the expanded region. In other words, a larger bore surface area provides a greater region over which bending can occur. Consequently, increasing the hosel bore depth enlarges the stress dispersion region, thereby decreasing stress concentration and reducing risk of failure or the occurrence of visible stress marks.Example V—Hosel Wall Thickness Relative to Material Hardness

[0223] Example V provides a comparison between examples of the club head described herein comprising different combinations of material hardness and hosel wall thickness, described in detail below. More specifically, Example V discusses the effect of the interaction between material hardness and wall thickness on the force required to bend the hosel.

[0224] A first exemplary club head (hereafter referred to as “Exemplary Club Head 1-8620”) comprises a hosel wall thickness that is approximately 0.066 inch thick in an upper region, approximately 0.077 inch thick in a middle region, and ranging from 0.075-0.276 inch thick in a lower region. Exemplary Club Head 1-8620 is made of a 8620 steel alloy having a yield strength of 52 ksi and a hardness value of 85 HRB. A second exemplary club head (hereafter referred to as “Exemplary Club Head 2-8620”) comprises a hosel wall thickness that is approximately 0.066 inch thick in an upper region, approximately 0.077 inch thick in a middle region, and ranging from 0.078-0.279 inch thick in a lower region. Exemplary Club Head 2-8620 is made of a 8620 steel alloy having a yield strength of 52 ksi and a hardness value of 85 HRB. A third exemplary club head (hereafter referred to as “Exemplary Club Head 3-8620”) comprises a hosel wall thickness that is approximately 0.066 inch thick in an upper region, approximately 0.077 inch thick in a middle region, and ranging from 0.081-0.282 inch thick in a lower region. Exemplary Club Head 3-8620 is made of a 8620 steel alloy having a yield strength of 52 ksi and a hardness value of 85 HRB.

[0225] A fourth exemplary club head (hereafter referred to as “Exemplary Club Head 1-431”) comprises a hosel wall thickness that is approximately 0.066 inch thick in an upper region, approximately 0.077 inch thick in a middle region, and ranging from 0.075-0.276 inch thick in a lower region. Exemplary Club Head 1-431 is made of a 431 stainless steel material having a yield strength of 80 ksi and a hardness value of 24 HRC. A fifth exemplary club head (hereafter referred to as “Exemplary Club Head 2-431”) comprises a hosel wall thickness that is approximately 0.066 inch thick in an upper region, approximately 0.077 inch thick in a middle region, and ranging from 0.078-0.279 inch thick in a lower region. Exemplary Club Head 2-431 is made of a 431 stainless steel material having a yield strength of 80 ksi and a hardness value of 24 HRC. A sixth exemplary club head (hereafter referred to as “Exemplary Club Head 3-431”) comprises a hosel wall thickness that is approximately 0.066 inch thick in an upper region, approximately 0.077 inch thick in a middle region, and ranging from 0.081-0.282 inch thick in a lower region. Exemplary Club Head 3-431 is made of a 431 stainless steel material having a yield strength of 80 ksi and a hardness value of 24 HRC.

[0226] A seventh exemplary club head (hereafter referred to as “Exemplary Club Head 1-17-4”) comprises a hosel wall thickness that is approximately 0.066 inch thick in an upper region, approximately 0.077 inch thick in a middle region, and ranging from 0.075-0.276 inch thick in a lower region. Exemplary Club Head 1-17-4 is made of a 17-4 stainless steel material having a yield strength of 115 ksi and a hardness value of 32 HRC. An eighth exemplary club head (hereafter referred to as “Exemplary Club Head 2-17-4”) comprises a hosel wall thickness that is approximately 0.066 inch thick in an upper region, approximately 0.077 inch thick in a middle region, and ranging from 0.078-0.279 inch thick in a lower region. Exemplary Club Head 2-17-4 is made of a 17-4 stainless steel material having a yield strength of 115 ksi and a hardness value of 32 HRC. A ninth exemplary club head (hereafter referred to as “Exemplary Club Head 3-17-4”) comprises a hosel wall thickness that is approximately 0.066 inch thick in an upper region, approximately 0.077 inch thick in a middle region, and ranging from 0.081-0.282 inch thick in a lower region. Exemplary Club Head 3-17-4 is made of a 17-4 stainless steel material having a yield strength of 115 ksi and a hardness value of 32 HRC.

[0227] The exemplary club heads described above comprise the same body structure and dimensions, including volume and hosel bore depth and geometry. The exemplary club heads described above club heads vary only in material and lower region hosel wall thickness. The differences in density of the various materials lead to corresponding differences in mass. Differences in hosel wall thickness provide minor additional variations in mass.

[0228] Results illustrated a decrease in magnitude of stress experienced during bending of the hosel resulting from an increase in hardness, and further illustrated a decrease in magnitude of stress experienced during bending of the hosel resulting from an increase in hosel wall thickness. Typically, an increase in material hardness leads to greater stress concentration, but a lower degree of maximum stress experienced and a lower amount of bending when force is kept constant.

[0229] Findings further showed that by altering hosel wall thickness, a similar amount of force input can be provided no matter the material of the hosel. For example, if a material is used for the hosel with a higher hardness and yield strength, the hosel wall thickness needs to be decreased to maintain the level of required force input. Focusing on hosel wall thickness and material properties provides the assembler with a consistent expectation of force, and therefore a consistent feel, when adjusting the loft and lie of a club head post-manufacturing.Example VI—Relationship Between Hosel Length, Head Frequency, and Acoustic Characteristics

[0230] Example VI provides an analytical comparison between club head frequency and its impact on perceived sound characteristics. Particularly, the following analysis utilizes club head modal testing to compare frequencies at mode 7, mode 9, and mode 10. Moreover, the frequencies at these modes were shown to correspond with perceived sound properties.

[0231] While sound perception is inherently subjective and can vary between golfers, trends have determined that certain acoustic characteristics are regarded as favorable. These acoustic characteristics differ between categories of clubs (i.e. player-style irons and game improvement irons); however, categorically similar club heads prove to define similarly favorable sound properties. One method for describing sound properties is through modal analysis. Specifically, modal analysis tests provide quantitative explanations for sound perception in the form of club head frequencies. For this study, club head frequencies at modes 7, 9, and 10 were examined in relation to perceived sound feedback.

[0232] This study established frequency thresholds for both player-style and game improvement irons, providing quantitative criteria to define what constitutes a ‘good-sounding’ club head. Specifically, two club heads from each category with different modal frequency characteristics were analyzed. Based on this analysis, a frequency threshold was determined for each club head, indicating the frequency range to achieve a desirable club head sound.

[0233] For the game improvement iron category, two 7-iron models were compared at three different modes: mode 7, mode 9, and mode 10. Game Improvement Club Head #1 and Game Improvement Club Head #2 comprised ample offset, a rear cavity to optimize perimeter weighting and forgiveness, and a relatively large size to produce confidence. However, Game Improvement Club Head #2 comprised a different badge configuration within the rear cavity than Game Improvement Club Head #1. Moreover, the two game improvement club heads incorporated minor shaping differences in the top rail and hosel. The influence of club head shaping-particularly in the hosel-on club head sound is further detailed in Example VII below.TABLE IIIModal frequencies of two game improvement club heads Game Improvement Club Game Improvement Club Modal Frequency Head #1 Head #2Mode 7 (Hz) 2417 2893 Mode 9 (Hz) 4191 4635 Mode 10 (Hz) 6198 6393

[0234] As illustrated in Table III, Game Improvement Club Head #1 further defined a modal frequency of 2417 at mode 7, 4191 at mode 9, and 6198 at mode 10. Alternatively, Game Improvement Club Head #2 defined a modal frequency of 2893 at mode 7, 4635 at mode 9, and 6393 at mode 10. Table III above illustrates the modal frequencies of each club head.

[0235] During a player test, a group of twenty-five golfers were tasked with hitting a representative number of shots with Game Improvement Club Head #1 and Game Improvement Club Head #2. During testing, the golfers were asked to consider the club head sound, specifically. After the test, it was calculated that 56% of the golfers rated game improvement club head #1 as having a satisfactory sound profile, while 90% of the golfers rated game improvement club head #2 as having a satisfactory sound profile. As such, it was determined that a higher club head frequency tends to lead to a more satisfactory sound. Moreover, due to the significant increase in sound perception between the two game improvement club heads, a frequency threshold delineating a good sounding game improvement 7-iron was postulated to be over 4300 Hz at mode 9 and 6300 Hz at mode 10.

[0236] Additionally, two 7-irons models were compared for the player-preferred iron category. The player-preferred iron club heads comprised minimal offset, limited perimeter weighting, a sleek top-line, and a relatively compact size to optimize shot shaping. However, Player-Preferred Club Head #1 comprised a different rear cavity shape and configuration than Player-Preferred Club Head #2. Moreover, the two player-preferred club heads incorporated minor shaping differences in the top rail and hosel. As previously mentioned, the influence of club head shaping-particularly in the hosel-on club head sound is further detailed in Example VII below.TABLE IVModal frequencies of two player-preferred club heads Player-Preferred Club Player-Preferred Club Modal Frequency Head #1 Head #2Mode 7 (Hz) 3127 3440 Mode 9 (Hz) 5832 6608 Mode 10 (Hz) 7708 8334

[0237] As illustrated in Table IV, Player-Preferred Club Head #1 further defined a modal frequency of 3127 at mode 7, 5832 at mode 9, and 7708 at mode 10. Alternatively, Player-Preferred Club Head #2 defined a modal frequency of 3440 at mode 7, 6608 at mode 9, and 8334 at mode 10. Table IV above illustrates the modal frequencies of each player-preferred club head.

[0238] During a player test, a group of twenty-one golfers were tasked with hitting a representative number of shots with Player-Preferred Club Head #1 and Player-Preferred Club Head #2. During testing, the golfers were asked to regard the club head sound and acoustics, specifically. After testing, the participants compared the two club heads based on perceived sound properties. As such, participants were asked to compare sound desirability between club heads based on a scale of “Undesirable” to “Desirable.” In between these choices, there was: “Moderately Undesirable,”“Slightly Undesirable,”“Slightly Desirable,” and “Moderately Desirable.” Table V below illustrates the player test responses.TABLE VQualitative sound results between two player-preferred club headsSound FeedbackModeratelySlightlySlightlyModeratelyUndesirableUndesirableUndesirableDesirableDesirableDesirableTotal VotesPlayer-004106222PreferredClub Head#1Player-001461122PreferredClub Head#2

[0239] As shown in Table V, Player-Preferred Club Head #2 produced a more favorable sound profile than Player-Preferred Club Head #1. Specifically, 77% of participants rated the acoustics of Player-Preferred Club Head #2 as “Moderately Desirable” or “Desirable,” while only 4.5% of participants rated the acoustics as “Slightly Undesirable.” Alternatively, only 36% of participants rated the acoustics of Player-Preferred Club Head #1 as “Moderately Desirable” or “Desirable,” while 18% of participants rated the acoustics as “Slightly Undesirable.” Accordingly, the sound-frequency relationship previously observed in the game improvement club heads was further demonstrated in this study. Particularly, it was determined that the player-preferred club head with the higher club head frequency tends to lead to a more satisfactory sound. Moreover, due to the significant increase in sound perception between the two player-preferred club heads, a frequency threshold delineating a good sounding players 7-iron was postulated to be over 6000 Hz at mode 9 and 8000 Hz at mode 10.

[0240] As previously mentioned, satisfactory club head acoustic profiles may vary among golfers. However, the test results presented above suggest a relative consensus between club head frequency and appealing sound characteristics. Notably, game improvement club heads achieving a frequency threshold of 4300 Hz at mode 9 and 6300 Hz at mode 10 appeal to a broader spectrum of golfers than similar game improvement club heads with lower frequencies. Likewise, player-preferred club heads demonstrate similar sound proficiency when achieving a frequency threshold of 6000 Hz at mode 9 and 8000 Hz at mode 10 relative to lower frequency player-preferred club heads. Structural variations to the club heads may provide methods to achieving these club head frequencies, such as hosel length manipulation discussed below in Example VII.Example VII—Comparison of Sound Between One Embodiment of the Club Head Described Herein and A Control Club Head

[0241] Example VII provides a qualitative comparison illustrating the effect of a shortened hosel on acoustics (or “sound”). Specifically, described herein is a player test which evaluates qualitative improvements for a golf club head featuring different hosel lengths. In particular, this player test compared two iron-type club heads having similar structures. The player test compared cavity-back style irons having similar badges disposed within the cavities, but featured different hosel lengths. The test further compared the effect of the different structures on player satisfaction regarding the club head sound (or “acoustics”).

[0242] The first iron-type club head (hereafter referred to as the “exemplary club head”) comprised a rear cavity defining a badge. Moreover, the exemplary club head comprised a hosel length of 2.73 inches measured perpendicularly from the hosel top surface to the ground plane.

[0243] The second iron-type club head (hereafter referred to as the “control club head”) differed from the exemplary club head. Specifically, the control club head comprised a rear cavity defining a similar badge to that of the exemplary club head. However, unlike the exemplary club head, the control club head comprised a longer hosel length than that of the exemplary club head. Specifically, the control club head comprised a hosel length of 2.91 inches measured perpendicularly from the hosel top surface to the ground plane.

[0244] The player test was conducted to compare the perceived sound feedback of a 7-iron model of the exemplary club head, featuring the short hosel (i.e. 2.73 inch), with that of a 7-iron model of the control club head (i.e. 2.91 inch). The player test involved thirty low-handicap players who were surveyed about their experience hitting the clubs as they related to sound and acoustics. During the test, each player would hit ten golf shots with each of the control and exemplary clubs. The players tested each club head under similar conditions, with a typical ball-striking surface, and wherein the iron-type club heads included similar shaft lengths and lofts. Thereafter, the players rated their experiences with the exemplary club head and the control club head.

[0245] After testing, the participants compared the two club heads based on perceived sound properties. As such, participants were asked to compare sound desirability between club heads based on a scale of “Much Less Desirable” to “Much More Desirable.” In between these choices, there was: “Moderately Less Desirable,”“Slightly Less Desirable,”“No Difference,”“Slightly More Desirable,” and “Moderately More Desirable.”“Much Less Desirable” represented a substantial decrease in satisfaction relative to the control club head. “Moderately Less Desirable” represented a decrease in satisfaction relative to the control club head. “Slightly Less Desirable” represented a slight decrease in satisfaction relative to the control club head. “No Difference” represented similar satisfaction between the exemplary club head and the control club head. “Slightly More Desirable” represented a moderate increase in satisfaction relative to the control club head. “Moderately More Desirable” represented a substantial increase in satisfaction relative to the control club head. “Much More Desirable” represented a substantial increase in satisfaction relative to the control club head.TABLE VIQualitative sound results between the exemplary and control club headsSound FeedbackMuchModeratelySlightlySlightlyModeratelyMuchLessLessLessNoMoreMoreMoreTotalDesirableDesirableDesirableDifferenceDesirableDesirableDesirableVotesExemplary Club 124693530Head (7i)TABLE VIICompiled sound results between the exemplary and control club heads FEEDBACKNumber of Participants who Voted Slightly More Desirable, 17 Moderately More Desirable, or Much More Desirable Number of Participants who Voted No Difference 6 Total Number Participants 30 Percentage of Participants who Voted Slightly More Desirable, 47% Moderately More Desirable, or Much More Desirable Percentage of Participants who Voted No Difference or Better 77%Tables VI and VII above exhibit participant responses comparing the exemplary club head to the control club head for sound feedback. Tables VII above illustrates the percentage of players who ranked the exemplary club head as “No Difference,”“Slightly More Desirable,”“Moderately More Desirable,” or “Much More Desirable” than the control club head for feedback. The exemplary club head was rated “No Difference,”“Slightly More Desirable,”“Moderately More Desirable,” or “Much More Desirable” when compared to the control club head by 77% of the participants for the 7-iron. Further, the exemplary club head was rated “Slightly More Desirable,”“Moderately More Desirable,” or “Much More Desirable” when compared to the control club head by 47% of the participants for the 7-iron.

[0247] The test resulted in the exemplary club head outperforming the qualitative parameters of the control club head (e.g., perceived sound and acoustics). The participants in the player test felt the exemplary club head had a better sound than the control club head and this sound / acoustic improvement was attributed to the shorter hosel length of the exemplary club head. As confirmed below, the shorter hosel length increases the frequency of the golf club head, thereby leading to a more pleasing sound / acoustic response.

[0248] Example VI described the frequency threshold for game improvement and player-preferred club heads to achieve a pleasing acoustic profile. Particularly, increasing the club head frequency for both categories of club heads resulted in a more satisfying club head sound. As outlined in the aforementioned player test, illustrated in Tables VI and VII, decreasing the hosel length improves the sound profile. This phenomenon can further be described by analyzing the relationship between club head frequency and hosel length.

[0249] These results were confirmed by the player perception test of the current Example (VII). Furthermore, FIG. 46 illustrates the relationship between club head frequency and the decrease in hosel length. Specifically, there is a linear relationship between club head frequency (Hz) and the decrease in hosel length (in.). For this illustration, a game improvement club head and player-preferred club head with initial hosel lengths of 2.82 in. and 2.74 in., respectively, were analyzed. Modal frequency software measured each club head as the respective hosel lengths were shortened. FIG. 46 illustrates that for a game improvement club head and a player-preferred club head, roughly every 0.075″ of hosel shortening provides an extra 100 Hz in club head frequency.

[0250] Club head acoustics play a key role in determining a player's perception of the club head's quality and performance. There are several structural design concepts that can influence club head acoustics. Shortening the hosel length, for instance, has shown to have a significant impact on club head sound perception. This can further be described by the impact that hosel length has on club head frequency. Particularly, a shorter hosel length leads to an increase in club head frequency, helping it reach specific frequency thresholds linked to favorable acoustic performance (see Example VI above).Example VIII—Comparison of Performance Between One Embodiment of the Club Head Described Herein and A Control Club Head

[0251] Described herein is a performance test that compared two iron-type club heads similar in build but for hosel lengths and badge configurations. This Example shows that the weight saved by shortening the hosel can be used in an application of a weighted badge. The performance test compared cavity-back style irons having similar body shapes but comprising different hosel lengths and badge configurations. The different hosel lengths and badge configurations produced differences in mass properties (i.e., CG characteristics) and performance characteristics, described below.

[0252] The first iron-type club head (hereafter referred to as the “control club head”) comprised a rear cavity, a unitary badge disposed within the rear cavity, and a standard hosel length of 2.73 inches. Moreover, the second iron-type club head (hereafter referred to as the “exemplary club head”) comprised a rear cavity, a weighted badge comprising a separate weight member, and a hosel length of 2.43 inches. The weighted badge included roughly 8.4 grams of weight savings from the shorter hosel configuration. Therefore, two factors changed over the control club head: the weighted badge to lower CG and the saved weight by shortening the hosel length. The hosel length defines the distance measured perpendicular from the hosel top surface to the ground plane.TABLE VIIICG comparison between the exemplary and control club heads Club CGy (in.) CGz (in.)Control Club Head 0.515 0.57 Exemplary Club Head 0.495 0.57

[0253] Table VIII above illustrates the CG locations, measured relative to the club head leading edge, of the control and exemplary club heads. A positive CGy measurement indicates a CG location above the leading edge. Similarly, a positive CGz measurement indicates a rearward CG location relative to the leading edge. As shown in Table VIII, the combination of the weighted badge and the shorter hosel length of the exemplary club head improves mass distribution compared to the control club head. Specifically, the exemplary club head comprises a lower center of gravity, described by the CGy distance, without affecting the CGz location. A lower club head CG also corresponds to improved launch and spin characteristics.

[0254] A computer-simulated analysis further compared the weighted badge and shorter hosel performance of the exemplary club head to the unitary badge and longer hosel performance of the control club head. The computer simulation examined the ball speeds of each club head. During simulations, the exemplary club head experienced a 0.2 mph increase in ball speed, on average, compared to the control club head. The ball speed improvement is attributed to the lower club head CG of the exemplary club head, provided by the shorter hosel length and the inclusion of the weighted badge.

[0255] Replacement of one or more claimed elements constitutes reconstruction and not repair. Additionally, benefits, other advantages, and solutions to problems have been described with regard to specific embodiments. The benefits, advantages, solutions to problems, and any element or elements that may cause any benefit, advantage, or solution to occur or become more pronounced, however, are not to be construed as critical, required, or essential features or elements of any or all of the claims, unless such benefits, advantages, solutions, or elements are expressly stated in such claims.

[0256] As the rules to golf may change from time to time (e.g., new regulations may be adopted or old rules may be eliminated or modified by golf standard organizations and / or governing bodies such as the United States Golf Association (USGA), the Royal and Ancient Golf Club of St. Andrews (R&A), etc.), golf equipment related to the apparatus, methods, and articles of manufacture described herein may be conforming or non-conforming to the rules of golf at any particular time. Accordingly, golf equipment related to the apparatus, methods, and articles of manufacture described herein may be advertised, offered for sale, and / or sold as conforming or non-conforming golf equipment. The apparatus, methods, and articles of manufacture described herein are not limited in this regard.

[0257] While the above examples may be described in connection with a iron-type golf club, the apparatus, methods, and articles of manufacture described herein may be applicable to other types of golf club such as a driver wood-type golf club, a fairway wood-type golf club, a hybrid-type golf club, an iron-type golf club, a wedge-type golf club, or a putter-type golf club. Alternatively, the apparatus, methods, and articles of manufacture described herein may be applicable to other types of sports equipment such as a hockey stick, a tennis racket, a fishing pole, a ski pole, etc.

[0258] Moreover, embodiments and limitations disclosed herein are not dedicated to the public under the doctrine of dedication if the embodiments and / or limitations: (1) are not expressly claimed in the claims; and (2) are or are potentially equivalents of express elements and / or limitations in the claims under the doctrine of equivalents.

[0259] Various features and advantages of the disclosure are set forth in the following clauses and claims.

[0260] Clause 1: An iron-type club head, comprising: a club head body, including: a strike face with a strike face front surface intended to impact a golf ball; a strike face rear surface opposite the strike face front surface; a heel end; a toe end, opposite the heel end; a hosel, adjacent the heel end and configured to receive a shaft, the hosel comprising: a hosel bore proximal end defined by a hosel outer transition plane; a hosel bore distal end; a hosel axis extending through a geometric center of a hosel bore tip between the hosel bore proximal end and the hosel bore distal end; a hosel length, measured between the hosel bore distal end and the hosel outer transition plane between 0.75 inch and 2.25 inches; and the hosel does not comprise a tip weight; an interior cavity, in open communication with an exterior of the iron-type club head; and a rear on an opposite side of the interior cavity from the strike face comprising an interior cavity opening perimeter circumscribing the rear and defining an opening into the interior cavity; a mass pad formed as an integral part of the club head body and defining a mass pad depth which varies in a top rail-to-sole direction; a strut extending between two non-adjacent portions of the interior cavity opening perimeter, the strut comprising: a strut angle between 15 degrees and 165 degrees; a strut width between 0.10 inch and 0.60 inch; and an insert undercut further comprising an insert undercut width of less than 0.55 inch; and an insert, comprising: an insert front surface; an insert rear surface opposite the insert front surface and adhesively secured to the strike face rear surface; at least one aperture configured to receive a weight member; and at least one weight member.

[0261] Clause 2: The iron-type club head of clause 1, wherein the hosel length is between 0.75 inch and 1.25 inches.

[0262] Clause 3: The iron-type club head of clause 1, wherein the strut angle is between 45 degrees and 60 degrees.

[0263] Clause 4: The iron-type club head of clause 1, wherein the strut width is between 0.20 inches and 0.30 inches.

[0264] Clause 5: The iron-type club head of clause 4, wherein the insert undercut width is less than 0.30 inches.

[0265] Clause 6: The iron-type club head of clause 1, wherein the insert comprises an insert thickness between 0.50 inch and 1.50 inches measured between the insert front surface and the insert rear surface in a direction perpendicular to a loft plane.

[0266] Clause 7: The iron-type club head of clause 6, wherein the insert thickness is variable.

[0267] Clause 8: The iron-type club head of clause 1, wherein the insert comprises an insert surface area ratio defined as the ratio between a surface area of the insert rear surface and a surface area of the strike face rear surface which is greater than 0.700.

[0268] Clause 9: The iron-type club head of clause 1, wherein an insert perimeter wall and the interior cavity opening perimeter are separated by a gap.

[0269] Clause 10: The iron-type club head of clause 9, wherein the gap defines a gap width between 0.01 inch and 0.05 inch which is variable about the interior cavity opening perimeter.

[0270] Clause 11: An iron-type club head, comprising: a club head body, comprising: a strike face, a top rail, a sole, a toe end, a heel end, and a hosel; a strike face front surface intended for impacting a golf ball and a strike face rear surface opposite the strike face front surface; an interior cavity defined by an area partially enclosed by the top rail, sole, heel end, toe end, and rear surface of the strike face; a hosel bore extending into the hosel and defining a hosel bore length measured from a hosel bore proximal end to the hosel bore distal end; wherein the hosel length is less than the hosel bore length; a hosel length measured from a hosel bore distal end to a transition plane along a hosel axis; and an insert, comprising: an insert rear surface permanently affixed to the strike face rear surface; an insert volume less than a volume of the interior cavity; and a plurality of weight members permanently affixed to the insert, wherein the plurality of weight members are selected from a group of weight members which have a mass of between 5 grams and 15 grams.

[0271] Clause 12: The iron-type club head of clause 11, wherein the hosel bore height is between 120% and 130% of the hosel length.

[0272] Clause 13: The iron-type club head of clause 11, wherein the interior cavity comprises an interior cavity volume and the insert comprises an insert volume which is greater than 40% of the interior cavity volume.

[0273] Clause 14: The iron-type club head of clause 11, wherein the strike face comprises a maximum strike face thickness and a minimum strike face thickness which is less than the maximum strike face thickness.

[0274] Clause 15: The iron-type club head of clause 11, wherein minimum strike face thickness is between 70% and 75% of a maximum strike face thickness.

[0275] Clause 16: An iron-type club head body, comprising: a strike face with a strike face front surface intended to impact a golf ball and a strike face rear surface opposite the strike face front surface; a heel end; a toe end, opposite the heel end; a hosel, adjacent the heel end and configured to receive a shaft; an interior cavity, in open communication with an exterior of the iron-type club head body; a rear on an opposite side of the interior cavity from the strike face, the rear comprising an interior cavity opening perimeter circumscribing the rear and defining an opening into the interior cavity; an insert, adhesively secured to the strike face rear surface and comprising: a first aperture; a first weight member disposed in the first aperture on a front surface of the insert proximate the toe and having a first weight member mass; a second aperture; a second weight member disposed in the second aperture on the front surface of the insert heelward of the first weight member and having a second weight member mass; wherein: the first weight member has a first weight member mass; the second weight member has a second weight member mass; the first weight member mass is less than the second weight member mass; the hosel does not receive a weight member; the hosel comprises a hosel bore, a hosel bore distal end, a hosel bore proximal end, and a hosel axis which passes through a geometric center of the hosel bore proximal end and a geometric center of the hosel bore hosel bore distal end; the hosel has a hosel bore height defined as a distance between the hosel bore distal end and the hosel bore proximal end measured along the hosel axis; the hosel bore height is between 1.0 inch and 2.5 inches; the first weight member has a first weight member center of gravity; the second weight member has a second weight member center of gravity; the iron-type club head body has a club head center of gravity; and a distance between the club head center of gravity and the first weight member center of gravity is greater than a distance between the club head center of gravity and the second weight member center of gravity.

[0276] Clause 17: The iron-type club head body of clause 16, wherein each of a material forming the first weight member and a material forming the second weight member has a density greater than a density of the material of the iron-type club head body.

[0277] Clause 18: The iron-type club head body of clause 16, wherein the insert comprises a tungsten-filled elastomeric material.

[0278] Clause 19: The iron-type club head body of clause 16, wherein the strike face comprises a maximum strike face thickness and a minimum strike face thickness, and the minimum strike face thickness is between 75% and 80% of the maximum strike face thickness.

[0279] Clause 20: The iron-type club head body of clause 16, wherein the strike face defines a strike face height which is between 1.5 inches and 2.2 inches.

[0280] Clause 21: An iron-type club head body comprising: a strike face with a strike face front surface intended to impact a golf ball and a strike face rear surface opposite the strike face front surface; a heel end a toe end, opposite the heel end; a hosel, adjacent the heel end and configured to receive a shaft; a rear comprising an opposite side of the interior cavity from the strike face; the rear comprising a sole bar having a sole bar top surface and a locating feature within the sole bar top surface; a badge secured to the sole bar top surface and to the strike face rear surface through an adhesive member, the badge having a badge top surface with a badge recess configured to receive a badge weight, the badge further comprising a protrusion that is configured to be received by the locating feature; wherein: the badge contacts a portion of the strike face rear surface above the adhesive member; the hosel does not receive a weight member; the hosel comprises a hosel bore, a hosel bore distal end, a hosel bore proximal end, and a hosel axis which passes through a geometric center of the hosel bore proximal end and a geometric center of the hosel bore hosel bore distal end; the hosel has a hosel bore height defined as a distance between the hosel bore distal end and the hosel bore proximal end measured along the hosel axis; the hosel bore height is between 1.0 inch and 2.5 inches.

[0281] Clause 22: An iron-type club head comprising: an iron-type club head body and an insert; wherein: the insert further comprises an insert front surface and an insert rear surface opposite the insert front surface; the iron-type club head body further comprises a strike face, a top rail, a sole, a toe end, a heel end, and a hosel portion; wherein: the strike face further comprises a strike face front surface intended for impacting a golf ball and a strike face rear surface opposite the strike face front surface; and an interior cavity is defined by an area partially enclosed by the top rail, sole, heel end, toe end, and rear surface of the strike face; the insert rear surface is permanently affixed to the rear surface of the strike face; an insert volume is less than a volume of the interior cavity; a plurality of weight members are permanently affixed to the insert; and the plurality of weight members are selected from a group of weight members which have a mass of between 5 grams and 15 grams.

[0282] Replacement of one or more claimed elements constitutes reconstruction and not repair. Additionally, benefits, other advantages, and solutions to problems have been described with regard to specific embodiments. The benefits, advantages, solutions to problems, and any element or elements that may cause any benefit, advantage, or solution to occur or become more pronounced, however, are not to be construed as critical, required, or essential features or elements of any or all of the claims, unless such benefits, advantages, solutions, or elements are stated in such claim.

[0283] Moreover, embodiments and limitations disclosed herein are not dedicated to the public under the doctrine of dedication if the embodiments and / or limitations: (1) are not expressly claimed in the claims; and (2) are or are potentially equivalents of express elements and / or limitations in the claims under the doctrine of equivalents.

Examples

example i

Comparison of Mass Properties Between One Embodiment of Club Head Described Herein And Control Club Head

[0200]Example I provides a comparison between two embodiments of a traditional iron-type golf club head with typical hosel bore geometry and length, one having an external notch and the other with no notch, and a separate embodiment of a club head with the hosel bore geometry described herein with no external notch. More specifically, Example 1 discusses differences in CG and MOI between two traditional club heads and one embodiment of the club head with the low hosel geometry described above, as shown in Table 1.

[0201]As shown in FIG. 6A, the two traditional iron-type golf club head comprising a typical hosel geometry and a hosel notch (hereafter referred to as “Control Club Head 1” and “Control Club Head 2”). Also described herein is an exemplary embodiment having an iron-type golf club head without a notch, a shorter hosel bore geometry and wall tapering as described above. Con...

example ii

Comparison of Material Deformation From Bending Between One Embodiment of Club Head Described Herein and Control Club Head

[0209]Example II provides a comparison illustrating the effect of a lowered, or lengthened, hosel bore on ability to bend and development of highly visible surface deformation resulting from stress. Specifically, Example II compares one embodiment of the club head described herein, comprising an extended hosel bore lacking an external notch, and one embodiment of a traditional iron-type golf club head, comprising typical hosel bore geometry having an external notch.

[0210]The standard club (hereafter referred to as the “Control Club Head”) comprised a body having a heel, toe, upper portion, and a lower portion, a hosel, a hosel bore configured to connect the golf club head with a shaft, and a notch located below the hosel on the heel side of the body. The Exemplary club (hereafter referred to as the “Exemplary Club Head”) comprised a bore extending lower into the ...

example iii

Comparison of FEA Response to Applied Forces at Hosel

[0213]This example provides a qualitative comparison illustrating the effect of a lowered, or lengthened, hosel bore on concentration of stress. Specifically, Example III provides a comparison of stress dispersion based on surface area of one embodiment of the club head described herein, comprising a lowered hosel bore and omitting an external notch, and one embodiment of a traditional iron-type golf club head comprising typical hosel bore geometry and having an external notch.

[0214]Stress values at a site of bending for a standard golf club head were compared to those of an exemplary golf club head. The standard golf club head (hereafter referred to as the “Control Club Head”) comprised a crown, sole, face, rear, hosel, and hosel bore. The exemplary golf club head (hereafter referred to as the “Exemplary Club Head”) comprised similar features with a shortened hosel and lowered hosel bore compared to the standard club. With the ex...

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation in part of U.S. patent application Ser. No. 18 / 476,266 filed on Sep. 27, 2023, which claims the benefit of U.S. Provisional Application No. 63 / 377,324, filed Sep. 27, 2022. This application also claims the benefit of U.S. Provisional Patent Application No. 63 / 669,183, filed on Jul. 9, 2024, U.S. Provisional Patent Application No. 63 / 783,392, filed on Apr. 4, 2025, and U.S. Provisional Patent Application No. 63 / 837,742, filed on Jul. 2, 2025. The contents of all of the above described disclosures are fully incorporated by reference herein in their entirety.FIELD OF THE INVENTION

[0002] The present disclosure relates to a golf club, and more specifically to a hosel and weighting designs for golf club heads.BACKGROUND

[0003] Golfers will often customize a club or set of clubs to best suit their personal swing style, height, or combination of physical factors. Clubs are often customized by adjusting loft and lie angle to ensure the player's club face is lined up correctly at address. Typically, a golf club head is ordered with the specifications of a player's custom adjustments ahead of time, and that club is then manufactured according to those specifications. This can cause long lead times and can limit the ability to later adjust the club head specifications. It is advantageous, therefore, to facilitate bending of the face angle during assembly processes, post-manufacture, or post-fabrication. Such bending, however, increases the risk of deformation at the bend site, creating unsightly marks or negatively impacting durability of certain finishes such as chrome.

[0004] During manufacture, the face of a golf club is typically oriented relative to the hosel to obtain initial loft and lie angles. The golf club may be further manipulated, for example, by bending, post-fabrication, to obtain final loft and lie angles. As the hosel is bent further, the club will develop cosmetic flaws, such as stress marks, and / or will structurally fail. For example, conventional club heads are typically limited to approximately ±2 degrees of post-fabrication bending before developing stress marks or structurally failing. Thus, it would be advantageous to provide a golf club head that can withstand post-fabrication bending without substantial stress marks or failure.BRIEF DESCRIPTION OF THE DRAWINGS

[0005] The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.

[0006] FIG. 1A illustrates a front perspective view of an exemplary embodiment of a golf club head according to the present disclosure.

[0007] FIG. 1B illustrates 1 a front view of the exemplary golf club head of FIG. 1A.

[0008] FIG. 2 illustrates a top view of the exemplary golf club head of FIG. 1A.

[0009] FIG. 3 illustrates a rear perspective view of the exemplary golf club head of FIG. 1A.

[0010] FIG. 4 illustrates a toe side view of the exemplary golf club of FIG. 1A.

[0011] FIG. 5A illustrates a cross-sectional view of the exemplary golf club head of FIG. 1A, along the line 5A-5A of FIG. 2.

[0012] FIG. 5B illustrates stress concentration of a first section of the exemplary golf club of FIG. 1 during a first set of conditions.

[0013] FIG. 5C illustrates stress concentration of a second section of the exemplary golf club of FIG. 1 during a first set of conditions.

[0014] FIG. 5D illustrates stress concentration of a third section of the exemplary golf club of FIG. 1 during a first set of conditions.

[0015] FIG. 6A illustrates a cross-sectional view of a conventional golf club head, along the same line as that shown in FIG. 5A.

[0016] FIG. 6B illustrates stress concentration of a first section of the golf club of FIG. 6A during the first set of conditions.

[0017] FIG. 6C illustrates stress concentration of a second section of the golf club of FIG. 6A during the first set of conditions.

[0018] FIG. 6D illustrates stress concentration of a third section of the golf club of FIG. 6A during the first set of conditions.

[0019] FIG. 7 illustrates a front cross-sectional view of a standard golf club head, along the line 5A-5A of FIG. 2.

[0020] FIG. 8 illustrates a front, cross-sectional view of the exemplary golf club head of FIG. 1A, along the line 5A-5A of FIG. 2.

[0021] FIG. 9 illustrates a cross-sectional view of an example of an embodiment of a golf club head, along the line 5A-5A of FIG. 2.

[0022] FIG. 10 illustrates a cross-sectional view of the exemplary golf club head of FIG. 1A, along the line 10-10 of FIG. 1B.

[0023] FIG. 11 illustrates a cross-sectional view of the exemplary golf club head of FIG. 1A, along the line 11-11 of FIG. 1B.

[0024] FIG. 12 illustrates a cross-sectional view of the exemplary golf club head of FIG. 1A, along the line 12-12 of FIG. 1B.

[0025] FIG. 13 illustrates a perspective view with low opacity of a conventional golf club head, where the opacity has been lowered to display internal features.

[0026] FIG. 14 illustrates a perspective view with low opacity of an exemplary embodiment of a golf club head according to the present disclosure.

[0027] FIG. 15 illustrates a perspective view with low opacity of an exemplary embodiment of a golf club head according to the present disclosure.

[0028] FIG. 16 illustrates a top-down view of one embodiment of a golf club head having a weighted insert of the present invention.

[0029] FIG. 17 illustrates a bottom view of the golf club head of FIG. 16.

[0030] FIG. 18 illustrates a toe-side view of the golf club head of FIG. 16.

[0031] FIG. 19 illustrates a heel-side view of the golf club head of FIG. 16.

[0032] FIG. 20 illustrates a rear view of the golf club head of FIG. 16.

[0033] FIG. 21 illustrates a front view of the golf club head of FIG. 16.

[0034] FIG. 22 illustrates a perspective view of the golf club head of FIG. 16.

[0035] FIG. 23 illustrates a cross-sectional toe-side view of the golf club head of FIG. 16.

[0036] FIG. 24 illustrates a cross-sectional front-side view of the golf club of FIG. 16.

[0037] FIG. 25 illustrates a cross-sectional front-side view of traditional golf club head.

[0038] FIG. 26 illustrates another front view of the golf club head of FIG. 16.

[0039] FIG. 27 illustrates another toe-side view of the golf club head of FIG. 16.

[0040] FIG. 28 illustrates a top-down view of another embodiment of a golf club head having a weighted insert of the present invention.

[0041] FIG. 29 illustrates a bottom view of the golf club head of FIG. 28.

[0042] FIG. 30 illustrates a toe-side view of the golf club head of FIG. 28.

[0043] FIG. 31 illustrates a heel-side view of the golf club head of FIG. 28.

[0044] FIG. 32 illustrates a rear view of the golf club head of FIG. 28.

[0045] FIG. 33 illustrates a front view of the golf club head of FIG. 28.

[0046] FIG. 34 illustrates a perspective view of the golf club head of FIG. 28.

[0047] FIG. 35 illustrates a cross-sectional toe-side view of the golf club head of FIG. 28.

[0048] FIG. 36A illustrates an alternative rear view of the golf club head of FIG. 28.

[0049] FIG. 36B illustrates a detailed view of Section AA of FIG. 36A.

[0050] FIG. 37 illustrates a rear view of the golf club head of FIG. 28 with the insert and first weight member removed.

[0051] FIG. 38 illustrates a toe-side view of one embodiment of a weighted insert of the present invention.

[0052] FIG. 39 illustrates a heel-side view of the weighted insert of FIG. 38.

[0053] FIG. 40 illustrates a rear perspective exploded view of the insert of FIG. 38.

[0054] FIG. 41 illustrates a toe-side cross-sectional view of the weighted insert of FIG. 38.

[0055] FIG. 42 illustrates a perspective view of the weighted insert of FIG. 38.

[0056] FIG. 43 illustrates another perspective view of the weighted insert of FIG. 38.

[0057] FIG. 44 illustrates a rear view of the weighted insert of FIG. 38.

[0058] FIG. 45 illustrates a front view of the weighted insert of FIG. 38.

[0059] FIG. 46 illustrates a set of exemplary graphs comparing frequency and hosel length.

[0060] FIG. 47 illustrates a rear view of a golf club head with a weighted insert and shortened hosel bore of the present invention.

[0061] FIG. 48 illustrates a rear perspective view of the golf club head of FIG. 47, without the weighted insert.

[0062] FIG. 49 illustrates an elevation view of the golf club head with a weighted insert of FIG. 47 in cross-section.

[0063] FIG. 50 illustrates a rear perspective view of a golf club head that can receive a weighted insert of the present invention.

[0064] FIG. 51 illustrates a rear perspective view of a golf club head and a weighted insert of the present invention in cross-section.DEFINITIONS

[0065] For simplicity and clarity of illustration, the drawing figures illustrate the general manner of construction, and descriptions and details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the invention. Additionally, elements in the drawing figures are not necessarily drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of embodiments of the present invention. The same reference numerals in different figures denote the same elements.

[0066] The terms “first,”“second,”“third,”“fourth,”“fifth,” and the like in the description and in the claims, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms “include,” and “have,” and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, device, or apparatus that comprises a list of elements is not necessarily limited to those elements, but may include other elements not expressly listed or inherent to such process, method, system, article, device, or apparatus.

[0067] The terms “left,”“right,”“front,”“back,”“top,”“bottom,”“over,”“under,” as used herein, are for descriptive purposes and not necessarily for describing permanent relative positions. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the apparatus, methods, and / or articles of manufacture described herein are, for example, capable of operation in other orientations than those illustrated or otherwise described herein.

[0068] The terms “couple,”“coupled,”“couples,”“coupling,” as used herein refers to connecting two or more elements, mechanically or otherwise. Coupling (whether mechanical or otherwise) may be for any length of time, e.g., permanent or semi-permanent or only for an instant.

[0069] The term “strike face,” or “strike surface,” as used herein, refers to a club head front surface that is configured to strike a golf ball. The term strike face can be used interchangeably with the term “face.”

[0070] The term “hosel,” as used herein, refers to a heel-side member of the club head configured to connect the club body with the club shaft.

[0071] The term “geometric centerpoint,” or “face center” of the strike face, as used herein, can refer to a geometric centerpoint of the strike face perimeter 105, and at a midpoint of the face height of the strike face. In the same or other examples, the geometric centerpoint also can be centered with respect to an engineered impact zone, which can be defined by a region of grooves on the strike face. As another approach, the geometric centerpoint of the strike face can be located in accordance with the definition of a golf governing body such as the United States Golf Association (USGA).

[0072] The term “ground plane,” as used herein, can refer to a reference plane associated with the surface on which a golf ball is placed. The ground plane can be a horizontal plane tangent to the sole at an address position. The ground plane 160 is illustrated throughout the drawings including FIGS. 1B and 4.

[0073] The term “lie angle,” as used herein, can refer to an angle between a hosel axis, extending through the hosel, and the ground plane. The lie angle is measured from a front view.

[0074] The term “loft,” or “loft angle,” as used herein, can refer to an angle measured between the loft plane and the XY plane (defined below). The loft plane 1022 is illustrated in FIGS. 4 and 27.

[0075] An “XYZ” coordinate system of the golf club head, as used herein, is based upon the geometric center of the strike face. The golf club head dimensions as described herein can be measured based on a coordinate system as defined below. The geometric center of the strike face defines a coordinate system having an origin located at the geometric center of the strike face. The coordinate system defines an X axis, a Y axis, and a Z axis. The X axis extends through the geometric center of the strike face in a direction from the heel to the toe of the fairway-type club head. The Y axis extends through the geometric center of the strike face in a direction from the top rail to the sole of golf club head. The Y axis is perpendicular to the X axis. The Z axis extends through the geometric center of the strike face in a direction from the front end to the rear end of the golf club head. The Z axis is perpendicular to both the X axis and the Y axis.

[0076] The term or phrase “center of gravity position” or “CG location” as used herein refers to the location of the club head center of gravity (CG) with respect to the XYZ coordinate system, wherein the CG position is characterized by locations along the X-axis, the Y-axis, and the Z-axis. The term “CGx” can refer to the CG location along the X-axis, measured from the origin point. The term “CGy” can refer to the CG location along the Y-axis, measured from the origin point. The term “CGz” can refer to the CG location along the Z-axis, measured from the origin point.

[0077] The term or phrase “moment of inertia” (hereafter “MOI”) as used herein is a value derived using the center of gravity (CG) location. The MOI can be calculated by assuming the club head includes the body and the hosel structure. The term “MOIxx” or “Ixx” can refer to the MOI measured about the X′-axis. The term “MOIyy” or “Iyy” can refer to the MOI measured about the Y′-axis. The term “MOIzz” or “Izz” can refer to the MOI measured about the Z′-axis. The MOI values MOIxx, MOIyy, and MOIzz determine how forgiving the club head is for off-center impacts with a golf ball.

[0078] Other features and aspects will become apparent by consideration of the following detailed description and accompanying drawings. Before any embodiments of the disclosure are explained in detail, it should be understood that the disclosure is not limited in its application to the details or construction and the arrangement of components as set forth in the following description or as illustrated in the drawings. The disclosure is capable of supporting other embodiments and of being practiced or of being carried out in various ways. It should be understood that the description of specific embodiments is not intended to limit the disclosure from covering all modifications, equivalents and alternatives falling within the spirit and scope of the disclosure. It is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.

[0079] For ease of discussion and understanding, and for purposes of description only, the following detailed description illustrates a club head 100 as an (or an iron-type club head). It should be appreciated that the iron is provided for purposes of illustration, and one or more of the attributes disclosed herein are not limited to an iron. The attributes can be used on any desired golf club, including an iron, wedge, putter, or other golf club where a resting face angle, hosel tilt, center of gravity (CG), or other attribute is desired to provide an improved performance and aesthetic for a player. For example, the club head 100 can include, but is not limited to, a one-iron, a two-iron, a three-iron, a four-iron, a five-iron, a six-iron, a seven-iron, an eight-iron, a nine-iron, a pitching wedge, a gap wedge, a utility wedge, a sand wedge, a lob wedge, and / or a putter. In addition, the club head 100 can have a loft that can range from approximately 3 degrees to approximately 65 degrees (including, but not limited to, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12, 12.5, 13, 13.5, 14, 14.5, 15, 15.5, 16, 16.5, 17, 17.5, 18, 18.5, 19, 19.5, 20, 20.5, 21, 21.5, 22, 22.5, 23, 23.5, 24, 24.5, 25, 25.5, 26, 26.5, 27, 27.5, 28, 28.5, 29, 29.5, 30, 30.5, 31, 31.5, 32, 32.5, 33, 33.5, 34, 34.5, 35, 35.5, 36, 36.5, 37, 37.5, 38, 38.5, 39, 39.5, 40, 40.5, 41, 41.5, 42, 42.5, 43, 43.5, 44, 44.5, 45, 45.5, 46, 46.5, 47, 47.5, 48, 48.5, 49, 49.5, 50, 50.5, 51, 51.5, 52, 52.5, 53, 53.5, 54, 54.5, 55, 55.5, 56, 56.5, 57, 57.5, 58, 58.5, 59, 59.5, 60, 60.5, 61. 61.5, 62, 62.5, 63, 63.5, 64, 64.5, and / or 65 degrees).

[0080] The term “iron,” as used herein, can, in some embodiments, refer to an iron-type golf club head having a loft angle that is less than approximately 50 degrees, less than approximately 49 degrees, less than approximately 48 degrees, less than approximately 47 degrees, less than approximately 46 degrees, less than approximately 45 degrees, less than approximately 44 degrees, less than approximately 43 degrees, less than approximately 42 degrees, less than approximately 41 degrees, or less than approximately 40 degrees. Further, in many embodiments, the loft angle of the club head is greater than approximately 16 degrees, greater than approximately 17 degrees, greater than approximately 18 degrees, greater than approximately 19 degrees, greater than approximately 20 degrees, greater than approximately 21 degrees, greater than approximately 22 degrees, greater than approximately 23 degrees, greater than approximately 24 degrees, or greater than approximately 25 degrees.

[0081] In many embodiments, the golf club head can be an “iron-type” club head. Iron-type club heads as used herein includes a plurality of iron-type club head subsets, such as, but not limited to, high lofted wedges constructed for short-game shots and low lofted irons constructed for driving long-range shots, otherwise known as “crossovers.”

[0082] In many embodiments, the loft angle of the iron or wedge-type golf club head is less than approximately 50 degrees, less than approximately 49 degrees, less than approximately 48 degrees, less than approximately 47 degrees, less than approximately 46 degrees, less than approximately 45 degrees, less than approximately 44 degrees, less than approximately 43 degrees, less than approximately 42 degrees, less than approximately 41 degrees, or less than approximately 40 degrees. Further, in many embodiments, the loft angle of the golf club head is greater than approximately 16 degrees, greater than approximately 17 degrees, greater than approximately 18 degrees, greater than approximately 19 degrees, greater than approximately 20 degrees, greater than approximately 21 degrees, greater than approximately 22 degrees, greater than approximately 23 degrees, greater than approximately 24 degrees, or greater than approximately 25 degrees.

[0083] In many embodiments, the iron or wedge-type golf club head can comprise a total volume of between 1.9 cubic inches and 2.7 cubic inches. In some embodiments, the total volume of the golf club head can be between 1.9 cubic inches and 2.4 cubic inches, 2.0 cubic inches and 2.5 cubic inches, 2.1 cubic inches and 2.6 cubic inches, 2.2 cubic inches and 2.7 cubic inches, 2.3 cubic inches and 2.7 cubic inches, or 2.4 cubic inches and 2.7 cubic inches. In other embodiments, the total volume of the club head 100 can be 1.9 cubic inches, 2.0 cubic inches, 2.1 cubic inches, 2.2 cubic inches, 2.3 cubic inches, 2.4 cubic inches, 2.5 cubic inches, 2.6 cubic inches, or 2.7 cubic inches.

[0084] In many embodiments, the golf club head can comprise a total mass of between 200 grams and 300 grams. In some embodiments, the golf club head can comprise a total mass of between 200 grams and 210 grams, 210 grams and 220 grams, 220 grams and 230 grams, 230 grams and 240 grams, 240 grams and 250 grams, 250 grams and 260 grams, 255 grams and 260 grams, 260 grams to 270 grams, 265 grams to 275 grams, 270 grams and 280 grams, 275 grams and 280 grams, or 250 grams and 270 grams. In other embodiments, the total mass can be 200 grams, 205 grams, 210 grams, 220 grams, 225 grams, 230 grams, 235 grams, 240 grams, 245 grams, 250 grams, 255 grams, 260 grams, 265 grams, 270 grams, 275 grams, 280 grams, 285 grams, 290 grams, 295 grams, or 300 grams.DETAILED DESCRIPTION

[0085] Described herein is a golf club having a shortened hosel which reduces mass in the high heel area and creates discretionary mass. The golf club head described herein allows for a range of loft and lie adjustability post-manufacture with maintained or reduced surface deformation and durability loss and also creates discretionary mass that can be placed strategically for performance benefits. In some embodiments, an iron-type golf club head comprises a top rail opposite a sole, a toe end opposite a heel end, a face opposite a rear end, and a hosel. The hosel comprises a hosel bore configured to receive a shaft. The hosel bore is defined within the hosel and extends the entire length of the hosel and into the club body. By extending into the club head body, the hosel bore length remains sufficient to receive a shaft despite the shortened hosel length. The shortened hosel and lengthened hosel bore described below allow the golf club head loft and lie angles to be highly adjustable post-manufacture ±4°. Further, this design disperses stress over a greater surface area and reduces stress concentration at the site of highest bend. The improved bending capacity reduces risk of failure and mitigates the occurrence of undesirable stress marks. Furthermore, the lengthened hosel bore enables a shortened hosel length, freeing up discretionary mass. Alternative means of swing weighting, disclosed below, can eliminate the need for a “tip weight.” Eliminating the “tip weight” enables a further reduction in hosel length, removing mass from the heel end and allowing mass to be redistributed to locations more advantageous for increasing club head moment of inertia (MOI) such as a weighted badge or sole mass pads in the heel end and / or toe end of the club head.

[0086] Referring now to FIGS. 1-15, the club head 100 includes a club head body 104 having a toe 108 (or a toe end 108) opposite a heel 112 (or a heel end 112). The club head body 104 also includes a top rail 114 (or a crown 114) opposite a sole 115. A front 123 (or front side 123) of the club head body 104 carries a strike face 120 (or a face plate 120 or a club face 120 or a strike face 120) that defines a strike face front surface 122. The strike face 120 is opposite a rear 118 (or a back 118 or a rear side 118). The strike face 120 can also include a plurality of grooves 125.

[0087] With specific reference toFIG. 3, the club head body 104 also defines an upper portion 126 and a lower portion 128. An interior cavity opening perimeter 129 (for embodiments with an open interior cavity 175 as shown in FIGS. 16-37) or ledge 129 (for embodiments with a closed interior cavity 175 as shown in FIG. 3) is positioned on the rear 118 and extends generally from the toe 108 to the heel 112. The upper portion 126 is bounded by the top rail 114 and the ledge 129. The lower portion 128 is bounded by the sole 115 and the ledge 129.

[0088] With reference specifically to FIGS. 1B, 2 and 4, the strike face front surface 122 of the club head 100 includes the face center (FC). The face center (FC) can be located at a geometric center point of a strike face perimeter 105, and at a midpoint of a height of the strike face front surface 122. In some examples, the face center (FC) can be centered with respect to an engineered impact zone. The engineered impact zone can be defined by a region of grooves 125 on the strike face front surface 122. Alternatively, the face center (FC) can be located in accordance with a definition established by a golf governing body, such as the United States Golf Association (USGA).I. Hosel and Hosel Bore

[0089] With reference to FIGS. 1A, 1B, and 5A, and as stated above, the club head 100 also includes a hosel 110 positioned at the heel 112 for connecting the club head 100 to a shaft. Club heads constructed according to the present invention have a lengthened hosel bore 150, as described in further detail below. This lengthened hosel bore increases the surface area of the hosel 110. Distributing bending stresses over the increased surface area of the hosel 110 facilitates a greater degree of post-manufacture bendability (lie angle adjustability) without reduced risk of failure and mitigated occurrence of undesirable stress marks. Further, the lengthened hosel bore 150 facilitates a greater degree of post-manufacture bendability without the need for an aesthetically displeasing notch such as those found in conventional club heads.

[0090] The hosel 110 defines a hosel axis 1055 (FIGS. 1B, 5A, 9) that extends through a center of the hosel 110. The hosel 110 extends between a hosel bore proximal end 152 (or a proximal end 152) and a hosel bore distal end 154 (or a distal end 154) to the golf club head) from the club head body 104. The proximal end 152 of the hosel 110 is defined by a hosel outer transition plane 1038 (or transition plane 1038) at a location where an outer surface of the hosel 110 transitions to the club head body 104 (e.g., the heel 112), as shown in FIG. 5A. The hosel outer transition plane 1038 is perpendicular to the hosel axis 1055.

[0091] The hosel 110 includes a hosel bore 150. The hosel bore 150 extends along the hosel axis 1055 and is configured to receive the golf club shaft that carries a grip. As illustrated, the hosel bore 150 defines a proximal end 152 (or hosel bore proximal end 152) that is that is positioned within the club head body 104 (and specifically, the heel 112), and a distal end 154 (or a hosel bore distal end 154) that is positioned at the distal end of the hosel 110. The hosel bore distal end 154 is an open end and the hosel bore proximal end 152 is a closed end. The hosel bore proximal end 152 defines the lower boundary of the hosel 110 within the club head body 104 at the hosel bore proximal end 152. As noted above, and in contrast to typical golf club heads, the hosel bore 150 of the club head described herein extends beyond the proximal end 152 of the hosel 110 and into the club head body 104. To be specific, the hosel bore 150 extends beyond the hosel 110 (whose end can be identified by the hosel outer transition plane 1038 shown in FIG. 5A), and into the heel 112 of the club head body. Extending the hosel bore 150 beyond the hosel 110 is important for facilitating bending of the hosel 110 post manufacture, as discussed in further detail below.1. Hosel Bore Extension into Club Body

[0092] The hosel bore 150 extends the entire length of the hosel 110 and into the club head body 104 to allow for bending of the hosel 110 along a greater surface area. Therefore, the hosel bore 150 comprises a length that is greater than the length of the hosel 110. Referring to FIG. 5A, the hosel 110 defines a hosel length (HL) measured from the distal end 154 (or hosel bore distal end 154) to the transition plane 1038 along the hosel axis 1055. Depending on the club head loft and makeup, the hosel length (HL) ranges inclusively between 0.75 inches and 2.25 inches. In some embodiments, the hosel length (HL) ranges inclusively between 1.0 inches and 1.75 inches. In some embodiments, the hosel length (HL) can range between 0.75 inch and 1.0 inch, 1.0 inch and 1.25 inches, 1.25 inches and 1.50 inches, 1.50 inches and 1.75 inches, 1.75 inches and 2.0 inches, or 2.0 inches and 2.25 inches.

[0093] The hosel bore 150 defines a hosel bore height (HBH) measured from the hosel bore proximal end 152 (or hosel bore proximal end 152) to the hosel bore distal end 154 (or hosel bore distal end 154), which aligns with the hosel bore distal end 154, along the hosel axis 1055. In some embodiments, the hosel bore height (HBH) ranges inclusively between 1.0 inches and 2.5 inches. In some embodiments, the hosel bore height (HBH) ranges inclusively between 1.3 inches and 2.2 inches. In some embodiments, the hosel bore height (HBH) can range between 1.0 inch and 1.1 inches, 1.1 inches, and 1.2 inches, 1.2 inches and 1.3 inches, 1.3 inches and 1.4 inches, 1.4 inches and 1.5 inches, 1.5 inches and 1.6 inches, 1.6 inches and 1.7 inches, 1.7 inches and 1.8 inches, 1.8 inches and 1.9 inches, 1.9 inches and 2.0 inches, 2.0 inches and 2.1 inches, 2.1 inches and 2.2 inches, 2.2 inches and 2.3 inches, 2.3 inches and 2.4 inches, or 2.4 inches and 2.5 inches.

[0094] According to the present disclosure, the hosel length (HL) is less than the hosel bore height (HBH), resulting in the hosel bore 150 extending past the hosel 110 and into the club head body 104. Extending the hosel bore 150 into the club head body 104 by a distance defined by the difference between the hosel bore height (HBH) and (HL) removes material and mass from the heel 112, thereby increasing discretionary mass and facilitating post-production bending of the club head 100 by allowing for bending over a greater surface area. In many embodiments, the hosel bore height (HBH) is at least 100% the hosel length (HL). In some embodiments, the hosel bore height (HBH) may be approximately 100% to 160% greater than the hosel length (HL). For example, the hosel bore height (HBH) can be approximately 100% to 110%, 110% to 120%, 120% to 130%, 130% to 140%, 140% to 150%, or 150% to 160% greater than the hosel length (HL). In some embodiments, the hosel bore height (HBH) is at least 100%, at least 110%, at least 120%, at least 130%, at least 140%, or at least 150% greater than the hosel length (HL).

[0095] The position and configuration of the hosel 110 and the hosel bore 150 contrast with conventional iron-type golf club heads, one of which is shown in FIG. 6A. First, the hosel length (HL) ranges from between 0.200 and 0.600 inches less than the hosel length (HL) of conventional iron-type golf club heads. Moreover, the smaller hosel length (HL), together with the tapered first zone 186, which can receive a tip weight 156, reduces the overall mass of the club head 100 by between 3 grams and 8 grams. These differences lead to a lower center of gravity (CG). That is, as noted above, the center of gravity (CG) along the y-axis 1050 is approximately 0.020 inch to 0.060 inch lower than conventional iron-type golf club heads.2. Hosel Bore Internal Geometries

[0096] The geometry of the club head 100 may influence the shape of the hosel bore 150. More specifically, a heel-to-toe transition 124 of the club head 100 may have an arcuate shape. As the hosel bore 150 extends further into the club head 100, the hosel axis 1055 and the heel-to-toe transition 124 converge, reducing the amount of club head material therebetween and creating an area of stress concentration. To maintain structural integrity, the hosel bore proximal end 152 can be shaped to maintain sufficient club head material between the hosel bore 150 and the heel-to-toe transition 124. In some embodiments, the hosel bore 150 includes a hosel bore tip 155 that generally tapers toward the hosel bore proximal end 152. For example, as best shown in FIG. 9, the hosel bore tip 155 has a frustoconical shape with a larger diameter at the hosel bore distal end 154 and a smaller diameter at the hosel bore proximal end 152 configured to maintain structural integrity at the heel-to-toe transition 124. Specifically, because of the external geometry of the club head, wherein the heel end 112 below the hosel curves in toward the body, space for the hosel bore 150 in that region is limited, constraining the bore to be narrower. The tapered hosel bore tip 155 allows for a longer hosel bore 150, whose thinner walls allow for bending to occur further into the club head body and, therefore, over a greater surface area. The tapered hosel bore tip 155 also removes additional mass from the heel of the club head 100, thereby further increasing discretionary mass.

[0097] The hosel bore 150 can define multiple hosel bore walls 158 characterized by locations relative to the club head body 104. For example, the hosel bore walls 158 can be characterized by proximity to the toe 108 or heel 112 sides, respectively, as a toe-side internal wall 198 and a heel-side internal wall 194. In many embodiments, the toe-side internal wall 198 and the heel-side internal wall 194 can be formed and rounded continuously.

[0098] The toe-side internal wall 198 can define a toe-side hosel angle 196 relative to the hosel axis 1055. The heel-side internal wall 194 can define a heel-side hosel angle 192 relative to the hosel axis 1055. The angled configuration of the internal walls 198, 194 creates the tapered effect of the hosel bore proximal end 152. The toe-side hosel angle 196 can range inclusively between 2.5° and 20°. In some embodiments, the toe-side hosel angle 196 can range inclusively between 2.5° to 5.0°, 5.0° to 7.5°, 7.5° to 10.0°, 10.0° to 12.5°, 12.5° to 15°, 15° to 17.5°, or 17.5° to 20°. The heel-side hosel angle 192 can also range inclusively between 2.5° and 20°. In some embodiments, the heel-side hosel angle 192 can range inclusively between 2.5° to 5.0°, 5.0° to 7.5°, 7.5° to 10.0°, 10.0° to 12.5°, 12.5° to 15°, 15° to 17.5°, or 17.5° to 20°.

[0099] In many embodiments, the toe-side hosel angle 196 and the heel-side hosel angle 192 are the same. In alternative embodiments, the toe-side hosel angle 196 and the heel-side hosel angle 192 differ. In particular, the heel-side hosel angle 192 can be larger than the toe-side hosel angle 196. Internal walls with differing angles will create an asymmetrical shape. In all embodiments, the toe-side hosel angle 196 and the heel-side hosel angle 192 are likely to change, and become asymmetrical, as a result of hosel bending. Therefore, toe-side and heel-side hosel angles 196, 192 refer only to these angles post-manufacturing and before bending.3. Other Considerations of Hosel Bore Extension

[0100] Extending the hosel bore 150 into the club head body 104 increases discretionary mass that can be used elsewhere on the club head 100 to move a center of gravity (CG) of the club head 100 to a desired location. With reference to FIGS. 1B, 2, and 4, the location of the center of gravity (CG) can be defined relative to a coordinate system establishing the x-axis 1040, a y-axis 1050, and a z-axis 1060. The face center (FC) defines an origin of the coordinate system including the axes 1040, 1050, 1060. The x-axis 1040 (shown in FIGS. 1B and 2) extends through the club head face center (FC) from toe 108 to the heel 112. The x-axis 1040 is positive towards the toe 108. The y-axis 1050 (shown in FIGS. 1B and 4) extends through the club head face center (FC) from the top rail 114 (or crown 114) to the sole 115. The y-axis 1050 is positive towards the top rail 114 (or crown 114). The y-axis 1050 is perpendicular to the x-axis 1040 when viewed from the front view (or from the strike face 120). The y-axis 1050 is oriented at an oblique angle to the hosel axis 1055. The z-axis 1060 (shown in FIGS. 2 and 4) extends through the face center (FC) from the strike face 120 to the rear 118 of the club head 100. The z-axis 1060 is positive towards the strike face 120. The z-axis 1060 is perpendicular to the x-axis 1040 and the y-axis 1050.

[0101] In the illustrated embodiment, the location of the center of gravity (CG) can be measured from the face center (FC). The center of gravity (CG) can be measured along the x-axis 1040 relative to the face center (FC) and is represented by CGx. The center of gravity (CG) can also be measured along the y-axis 1050 relative to the face center (FC) and is represented by CGy. The center of gravity (CG) can be measured along the z-axis 1060 face center (FC) and is represented by CGz. Moving the center of gravity (CG) towards the toe 108 or the heel 112 can be achieved by increasing or decreasing the distance along the x-axis 1040. Lowering the center of gravity (CG) can be achieved by decreasing the distance along the y-axis 1050. Moving the center of gravity (CG) rearward can be achieved by increasing the distance along the z-axis 1060. In other examples of embodiments, the center of gravity (CG) location can be measured from the leading edge 133 of the club head 100 (or from a furthest forward position of the club head 100).

[0102] In some embodiments, the center of gravity (CG) may be approximately aligned with the face center (FC) along the x-axis 1040 (i.e., CGx is approximately zero). In other embodiments, CGx may be located approximately-0.10 inches to approximately 0.10 inches from the face center (FC), as measured along the x-axis 1040. The club head 100 also has a CGy of approximately 0.10 inches to approximately 0.75 inches from the face center (FC), as measured along the y-axis 1050. In the illustrated embodiment, the CGy is between the face center (FC) and the sole 115. As a result of the hosel 110 position and configuration, the CGy is between 0.020 inch and 0.060 inch lower than conventional iron-type golf club heads (shown in FIG. 9A). As illustrated in Example 1 below, the CGy can be approximately 0.040 inches lower than in conventional iron-type golf club heads.

[0103] The hosel bore further can be characterized by a total bore volume. The total bore volume can be categorized into an upper bore volume and a lower bore volume with respect to other elements of the club head. For example, the bore volume can be categorized by an upper bore volume above the hosel outer transition plane 1038 and a lower volume below the hosel outer transition plane 1038. In some embodiments, the upper bore volume above the hosel outer transition plane 1038 is 60-95% of the total bore volume and the lower bore volume below the hosel outer transition plane 1038 is 5-40% of the total bore volume. For example, the upper bore volume above the hosel outer transition plane 1038 can be 60-65%. 65-70%, 70-75%, 75-80%, 80-85%, 85-90%, or 90-95% of the total bore volume. The lower bore volume below the hosel outer transition plane 1038 can be 5-10%, 10-15%, 15-20%, 20-25%, 25-30%, 30-35%, or 35-40% of the total bore volume. As illustrated in Example 1 below, the upper bore volume above the hosel outer transition plane 1038 can be 90% of the total bore volume and the lower bore volume below the hosel outer transition plane 1038 can be 10% of the total bore volume.

[0104] The hosel bore 150 can be measured with reference to a plurality of axes formed across the club head 100 and parallel to the ground plane 160, as illustrated in FIGS. 7 & 8. It is beneficial for the hosel bore 150 to extend into the club head body 104 below particular reference planes in order to reduce overall club mass, create discretionary mass for performance benefits, and ensure the hosel 110 is able to withstand bending up to ±6° without substantial surface deformation or wrinkling. In some examples, the hosel 110 is able to withstand bending up to ±2°, ±3°, ±4°, ±5°, or ±6°.

[0105] The upper bore volume and lower bore volume can be quantified by referencing the plurality of axes. In the address position, a first axis 1010 (hereafter referred to as “top-hosel axis”1010) is formed parallel to the ground plane 160 across the top-most edge of the hosel 110. A hosel height (HH) can be defined as the distance from the ground plane 160 to the top-hosel axis 1010. In some embodiments, the hosel height (HH) ranges inclusively between 1.5 inches and 2.75 inches. In many embodiments, the hosel height (HH) can range inclusively between 1.75 inches and 2.25 inches. For example, the hosel height (HH) can range inclusively between 1.75 inches and 1.85 inches, 1.85 inches and 1.95 inches, 1.95 inches and 2.05 inches, 2.05 inches and 2.15 inches, or between 2.15 inches and 2.25 inches. The hosel height (HH) can be approximately 5% to approximately 25% lower than the hosel height of conventional club heads. In some embodiments, the hosel height (HH) is 5-10%, 10-15%, 15-20%, or 20-25% lower than a hosel height of conventional club heads. As detailed in Example 1 below, the hosel height (HH) can be 8.6% lower than the hosel height (HH) of conventional club heads. In another embodiment of an exemplary club head, the hosel height (HH) can be 8.8% lower than the hosel height of conventional club heads.

[0106] In the address position, a second axis 1012 (hereafter referred to as “hosel-body axis”1012) is formed parallel to the ground plane 160 across the location at which the hosel 110 and club head body 104 meet. A hosel-body bore height 1017 can be defined between the ground plane 160 and the hosel-body axis 1012. The hosel bore volume can be characterized further by the percent of total volume that resides above or below the hosel-body axis 1012. In particular, a percentage of the hosel bore volume can be located below the hosel-body axis 1012. In some embodiments, the percentage of the hosel bore volume below the hosel-body axis 1012 can range inclusively between 5% and 40% of the hosel bore volume. In many embodiments, the percentage of the hosel bore volume below the hosel-body axis 1012 can range inclusively between 5% and 30% of the hosel bore volume. In some embodiments, the percentage of the hosel bore volume below the hosel-body axis 1012 is 5%-10%, 10%-15%, 15%-20%, or 20%-25% of the hosel bore volume.

[0107] A hosel-body ratio can be defined as the ratio between the percentage of the hosel bore volume above the hosel-body axis 1012 and the percentage of the hosel bore volume below the hosel-body axis 1012. In some embodiments, the hosel-body ratio, H1:H2, is approximately 1.5:0.025 to 1.5:0.250. In some embodiments, the hosel-body ratio H1:H2 can be between 1.5:0.025 and 1.5:0.050, 1.5:0.050 and 1.5:0.075, 1.5:0.075 and 1.5:0.100, 1.5:0.100 and 1.5:0.125, 1.5:0.125 and 1.5:0.150, 1.5:0.150 and 1.5:0.175, 1.5:0.175 and 1.5:0.200, 1.5:0.200 and 1.5:0.225, or 1.5:0.225 and 1.5:0.250.

[0108] In the address position, a third axis 1014 (hereafter referred to as “midline axis”1014) is formed parallel to the ground plane 160 across the geometric middle of the club head body 104. A midline hosel bore height 1015 of the hosel bore can be defined between the ground plane 160 and the midline axis 1014. A percentage of the hosel bore volume can be located below the midline axis 1014. In some embodiments, the percentage of the hosel bore volume below the midline axis 1014 can range inclusively between 1% and 20% of the hosel bore volume. In many embodiments, the percentage of the hosel bore volume below the midline axis 1014 can range inclusively between 1% and 15% of the hosel bore volume. In some embodiments, percentage of the hosel bore volume below the midline axis 1014 is 1%-5%, 5%-10%, or 10%-15% of the hosel bore volume.

[0109] The extension of the hosel bore 150 into the club head body 104 lowers the center of gravity (CG), reduces mass of the club head to create discretionary weight, and allows for the design to comprise a shortened hosel 110, which further reduces mass. Further, positioning the hosel bore 150 low within the club head body 104 ensures the bend point of the hosel 110 occurs where the wall thickness can withstand an increased amount of stress and allows bending to occur over a greater surface area, reducing the occurrence of highly concentrated stress. Therefore, the low position of the hosel bore 150 allows the club head 100 to be bent to a relatively high degree during loft and lie adjustments without the formation of visible stress marks or surface deformation.

[0110] In the address position, a fourth axis 1016 (hereafter referred to as “bottom-hosel axis”1016) is formed parallel to the ground plane 160 across the bottom-most edge of the hosel bore 150. A lower hosel bore height 1013 can be defined as the distance from the ground plane 160 to the bottom-hosel axis 1016. In some embodiments, the lower hosel bore height 1013 ranges inclusively between 0.25 inches and 1.0 inches. In many embodiments, the lower hosel bore height 1013 ranges inclusively between 0.25 inches and 0.75 inches. In some embodiments, the lower hosel bore height 1013 ranges between 0.25 inches and 0.35 inches, 0.35 inches and 0.45 inches, 0.45 inches and 0.55 inches, 0.55 inches and 0.65 inches, or between 0.65 inches and 0.75 inches. The lower hosel bore height 1013 can be approximately 40% to approximately 80% lower than a hosel bore of conventional club heads. In some embodiments, the lower hosel bore height 1013 is 40-50%, 50-60%, 60-70%, or 70-80% lower than a lower hosel bore height of conventional club heads. As discussed in Example I below, the lower hosel bore height 1013 can be 57.1% lower than a lower hosel bore height of a conventional club head. As discussed in Example I below, the lower hosel bore height 1013 can be 65.1% lower than a lower hosel bore height of another conventional club head.

[0111] A hosel-bore ratio can be defined as the ratio of hosel height (HH) to lower hosel bore height 1013. As discussed above, it is desirous for bending purposes to have a hosel bore 150 which extends into the club head body 104 while maintaining a shortened hosel height (HH). A large hosel-bore ratio is indicative of a hosel which has both a high surface area and shortened hosel height and is therefore an indication that a club head will be suitable for post-manufacture bending. In some embodiments disclosed herein, the hosel-bore ratio is 1.2:1.1 to 1.9:1.0. In many embodiments, the hosel-bore ratio is 1.25:1.15 to 1:75:1.1. The hosel bore 150 is longer than the hosel 110 and extends into the club head body 104. This hosel bore configuration removes mass in the upper portion 126 of the club head body 104 and lowers the overall center of gravity (CG), creating discretionary mass to further be applied for weight benefits. The extended hosel bore 150 allows for bending to occur further into the club head body, allowing for increased distribution of stress over a greater surface area. By extending the hosel bore 150 lower into the club head body 104, the walls at the hosel-body connection point and heel 112 are thinned, thus allowing for hosel 110 bending without displaying high stress marks. The lowered bore design maintains the ability to post-manufacture adjustments to loft and lie, while mitigating or completely avoiding the generation of visible stress marks and creates discretionary mass for club head performance benefits.4. Hosel Configurations

[0112] The thickness of the hosel walls affects the ability of the hosel to undergo post-manufacture bending and withstand accompanying stresses. With reference to FIGS. 5A and 9-12, the hosel bore 150 defines a hosel bore wall 158. Different regions of the hosel bore wall 158 located sequentially along its hosel bore height (HBH) have associated thicknesses T1, T2, T3 that are measured from an inner surface of the hosel bore 150 to an outer surface of the hosel 110 and / or to the heel 112. The thicknesses of the hosel bore wall 158 generally decrease from the proximal end 152 of the hosel bore 150 to the distal end 154 of the hosel bore 150. That is, the hosel bore wall 158 at the proximal end 152 has the first wall thickness T1 that is the greatest thickness, the hosel bore wall 158 at the distal end 154 has second thickness T2 that is the smallest thickness, and the hosel bore wall 158 between the proximal end 152 and the distal end 154 has a third thickness T3 that is smaller than the first thickness T1 and greater than the second thickness T2. In other words, the hosel bore wall 158 has a first zone 186, a second zone 188, and a third zone 190.

[0113] In FIG. 5A, the different zones 186, 188, 190 are indicated using dash-dot lines. These zones are merely exemplary and may be delineated in other ways. The first zone 186 is configured to at least partially receive the tip weight 156. In the illustrated embodiment, the entire tip weight 156 is positioned within the first zone 186. In some embodiments, the tip weight 156 may be positioned in both the first zone 186 and the third zone 190. The first zone 186 has the first wall thickness T1. The second zone 188 has the second wall thickness T2. The third zone 190 has the third wall thickness T3.

[0114] The thickness T1 of the hosel bore wall 158 is not uniform in the first zone 186 for two reasons. First, in some embodiments, at least a portion of the hosel bore wall 158 can be tapered relative to the hosel axis 1055, and second, a portion of the hosel bore wall 158 is made up of the heel 112, which has a curved exterior profile, and another portion of the hosel bore wall 158 nears the top rail 114, requiring additional material for structural stability. The first wall thickness T1 is larger on a top side of the hosel bore wall 158 than in the remainder of the hosel bore wall 158.

[0115] With reference to FIG. 10, to relate the thicknesses T1, T2, T3 of the hosel 110, the hosel bore 150 and hosel bore wall 158 can be compared to an analog clock in which a xh-axis 1045 extends between 12 o'clock and 6 o'clock, and a zh-axis 1065 extends between 3 o'clock and 9 o'clock. As shown, the xh-axis 1045 of the clock is parallel to and offset relative to an x-axis 1040 extending through a face center (FC) of the club head 100. In the illustrated embodiment, in the first zone 186, the thickness T1 of the hosel bore wall 158 is greatest between 12 o'clock and 3 o'clock because this is where the club head body 104 defines the hosel bore wall 158. Moreover, although not illustrated in FIGS. 10-12, the thickness T1 of the hosel bore wall 158 may generally decrease from the location between the first zone 186 and the third zone 190 in a direction toward the proximal end 152 of the hosel bore 150 and the club head body 104 in a region between 4 o'clock and 7 o'clock because this is where the exterior surface that transitions from the hosel 110 to the heel 112 is generally located. As shown, in FIGS. 11 and 12, the thicknesses T2 and T3 are generally uniform around the clock, with the thickness T3 being smaller than the thickness T2.

[0116] By maintaining a consistent wall thickness T2, T3 in the second zone 188 and third zone 190 and placing the proximal end 152 of the hosel bore 150 in the club head body 104, stress is distributed more evenly along the hosel length (HL), which leads to less localized stress and better bending results.

[0117] For additional guidance in describing the innovation herein, the x-axis 1040 and the z-axis 1060 are arranged to coincide with numbers on an analog clock in FIGS. 10-12. The z-axis 1060 extends between 12 o'clock (“12” through the strike face 120) and 6 o'clock (“6” through the rear 118), and the x-axis 1040 extends between 3 o'clock (“3” through the toe end 108) and 9 o'clock (“9” through the heel end 112), as also described above.

[0118] The first wall thickness T1 may range from approximately 0.05 inches to approximately 0.50 inches. The second wall thickness T2 may range from approximately 0.03 inches to approximately 0.3 inches. The third wall thickness T3 may range from approximately 0.02 inches to approximately 0.25 inches. The bore wall thicknesses T1, T2, T3 of each zone 186, 188, 190 may correspond to the type of the material of the club head body 104.

[0119] The respective thicknesses T1, T2, T3 of the hosel bore wall 158 in the different zones 186, 188, 190 are shown in greater detail in FIGS. 5A and 9-12. First, as shown in FIG. 5A, the thickness T1 of the hosel bore wall 158 in the first zone 186 on the heel end 112 corresponds to an exterior surface that transitions from the hosel 110 to the heel 112. Accordingly, as the exterior surface on the heel side transitions from the hosel 110 to the heel 112, the thickness T1 of the hosel bore wall 158 in the first zone 186 narrows. In other words, the thickness T1 of the hosel bore wall 158 is lowest on the heel end 112 at a location between the first zone 186 and the third zone 190 and smallest at the proximal end 152 of the hosel bore 150. Additionally, on the heel end 112, the thickness T1 of the hosel bore wall 158 narrows in a direction from the location between the first zone 186 and the third zone 190 in a direction toward the proximal end 152 of the hosel bore 150. Moreover, as shown, the hosel bore wall 158 of the first zone 186 is tapered relative to the hosel axis 1055 in some embodiments. The heel-side hosel angle 192 of taper between the hosel bore wall 158 and the hosel axis 1055 may range from approximately 2.5° to 5.0°, 5.0° to 7.5°, 7.5° to 10.0°, 10.0° to 12.5°, 12.5° to 15°, 15° to 17.5°, or 17.5° to 20°.

[0120] Further, with respect to FIGS. 10-12, different internal zones 186, 188, 190 of the hosel bore 150 define a first bore diameter 1030, second bore diameter 1032, and third bore diameter 1034 (e.g., diameters 1030, 1032, 1034) and the outer surface of the hosel 110 and the heel 112 defines a second dimension 1036. The bore diameters 1030, 1032, 1034 of the hosel bore 150 generally decrease from the proximal end 152 of the hosel bore 150 to the distal end of the hosel bore 150. That is, the hosel bore 150 at the proximal end 152 has a first bore diameter 1030 that is the largest diameter, the hosel bore 150 at the distal end 154 has a second bore diameter 1032 that is the smallest diameter, and the hosel bore 150 between the distal end 154 and proximal end 152 has a third bore diameter 1034 that is smaller than the first bore diameter 1030 and greater than the second bore diameter 1032. Also, correspondingly, the first bore diameter 1030 of the first zone 186 generally increases from the hosel bore proximal end 152 in a direction toward the hosel bore distal end 154. The second bore diameter 1032 is generally constant in the second zone 188 and third zone 190 (and around the clock defined by hosel axes 1045, 1065), but the second bore diameter 1032 is not constant in the first zone 186 because the first zone 186 has an oblong shape (as a result of the various thicknesses discussed above relative to the clock defined by hosel axes 1045, 1065). In other words, the first zone 186 has the first bore diameter 1030 and the variable second dimension 1036, the second zone 188 has the second bore diameter 1032 and a constant second dimension 1036, and the third zone 190 has the third bore diameter 1034 and a constant second dimension 1036, which is the same as the constant second dimension 1036 of the second zone 188.

[0121] The first bore diameter 1030 may range from approximately 0.05 inches to approximately 0.50 inches. The second bore diameter 1032 may range from approximately 0.25 inches to approximately 0.75 inches. The third bore diameter 1034 may range from approximately 0.10 inches to approximately 0.60 inches. The second dimension 1036 may range from approximately 0.50 inches to approximately 1.0 inches in the first zone 186, and the second dimension 1036 may range from approximately 0.25 inches to approximately 0.85 inches in the second zone 188 and third zone 190. Accordingly, the first bore diameter 1030 may be approximately 5% to approximately 50% of the largest second dimension 1036 of the first zone 186 and from approximately 20% to approximately 90% of the smallest second dimension 1036 of the first zone 186. The second bore diameter 1032 may be approximately 25% to approximately 90% of the second dimension 1036. The third bore diameter 1034 may be approximately 25% to approximately 90% of the second dimension 1036. The bore diameters 1030, 1032, 1034 and the second dimension 1036 are determined at least in part according to the type of the material of the club head body 104.

[0122] As shown in FIGS. 10-12, in illustrated embodiments, both the hosel 110 and the hosel bore 150 have circular cross-sections. That is, the second zone 188 and third zone 190 and the hosel bore 150 have circular cross-sections. In other embodiments, the hosel 110 may have a cross-section with a different shape and therefore the first zone 186 and second zone 188 may have cross-sections with a different shape. For example, the hosel 110 (and the second zone 188 and third zone 190 thereof) may have an ovular or elliptical cross-section. This modification would change the relative bore wall thicknesses T1, T2, T3 and the second dimension 1036 of the second zone 188 and third zone 190.

[0123] In alternative embodiments, as illustrated in FIGS. 14 and 15, the hosel bore can be formed continuously with an enclosed cavity within the body of the club head. As shown in the embodiment of FIG. 14, the cavity can extend partially into the club head and can be formed as part of a cavity back or muscle back iron-type club head, or could be used within a wedge, crossover, or putter. As shown in the embodiment of FIG. 15, the cavity can extend throughout the entirety of the club head body, forming a hollow-body iron-type club head. In these embodiments, the hosel bore can be open to the cavity, such that the hosel bore and cavity together form a single void. In other embodiments, the hosel bore and the cavity can be sectioned off with a partial or complete wall.

[0124] The partial cavity of the club head shown in FIG. 14 extends to align with a heel-most edge of the strike face in the illustrated embodiment. In other embodiments, the partial cavity can extend to a point heelward or toeward of the strike face edge. The shape and size of the cavity can be formed to best distribute stresses during hosel bending and during impact with a golf ball.

[0125] A thickness of the walls surrounding both the hosel bore and the enclosed cavity are illustrated to be consistent throughout. In other embodiments, however, the walls may comprise varying thickness which may taper or include thickened regions to provide necessary structural strength and rigidity, to improve manufacturability, or to encourage bending only in desired regions.

[0126] In some embodiments, the strike face 120 can comprise a first material of a first density. The club head body 104 can comprise a second material of a second density. In the illustrated embodiment, the strike face 120 can be the same material as the club head body 104 (and thereby the same densities).

[0127] The club head body 104 may comprise a material, such as steel, a steel alloy, or any other suitable material. In some embodiments, the club head body 104 can comprise a material of a density that is different over the strike face 120. The density of the club head body 104 material can range between 7.70 and 8.10 grams per cubic centimeter (hereafter “g / cc”). In some embodiments, the density of the body material can be 7.70 g / cc, 7.75 g / cc, 7.80 g / cc, 7.85 g / cc, 7.90 g / cc, 7.95 g / cc, 8.05 g / cc, or 8.10 g / cc.

[0128] The material of the club head body 104 can comprise a hardness measured on the Rockwell Scale (HRC). In many embodiments, the material hardness is related to the wall thicknesses T1, T2, T3 and bore diameters 1030, 1032, 1034 of the hosel 110. A club head comprising a material with a lower hardness will require a thicker area to reduce the appearances of stress bending. In order to maintain a similar degree of force required to bend the hosel, a golf club head made of a material with a greater hardness will require thinner hosel walls than a golf club head made of a material with a lower hardness. This is because a harder material will require greater force to incur deformation. It is preferable to establish a uniform assembly process by requiring a nearly constant amount of force to bend the hosel by modifying the wall thickness as needed based on material properties. Example V below details further the relationship between material hardness and hosel wall thickness.

[0129] In addition to the relational position of the hosel bore 150, other features of the club head 100 dictate performance characteristics such as the moments of inertia Ixx, Iyy and center of gravity (CG). The materials that form the club head body 104, the strike face 120, the toe weight 157, and the tip weight 156 can affect the mass distribution of the club head 100. Consequently, the moments of inertia Ixx, Iyy and center of gravity center of gravity (CG) of the club head 100 are also affected by the densities of the materials. Furthermore, the materials provide the strength and flexibility necessary for the club head 100. The club head 100 comprises one or more, two or more, three or more, or four or more materials. In some embodiments, the materials may be a first density, second density, third density, fourth density, fifth density or sixth density.

[0130] Moreover, because a portion of the hosel bore 150 extends into the club head body 104 (or heel 112), a portion of the tip weight 156 can reside partially or entirely within the club head body 104, when only a portion of the tip weight 156 resides in the club head body 104, a remainder of the tip weight 156 can reside in the hosel 110. The weight of the tip weight 156 can range between 0 grams and 18 grams. In some embodiments, the weight of the tip weight 156 can be 0 grams (in the embodiment where there is no tip weight), 1 grams, 2 grams, 3 grams, 4 grams, 5 grams, 6 grams, 7 grams, 8 grams, 9 grams, 10 grams, 11 grams, 12 grams, 13 grams, 14 grams, 15 grams, 16 grams, 17 grams, or 18 grams. In some embodiments, the tip weight 156 ranges between 0 grams and 9 grams. The tip weight 156 can comprise a material that is different over the material of the club head body 104. The tip weight 156 may be formed from the same or different material as the toe weight 157 and therefore comprises a high-density material, such as tungsten or any other suitable metal or metal alloy material.

[0131] In some embodiments, the density of the material(s) of the toe weight 157 and the tip weight 156, if present, can range between 1.1 g / cc and 19.6 g / cc. In some embodiments, the density of the tip weight 156 material can be 1.1 g / cc, 1.5 g / cc, 2.0 g / cc, 2.5 g / cc, 3.0 g / cc, 3.5 g / cc, 4.0 g / cc, 4.5 g / cc, 5.0 g / cc, 5.5 g / cc, 6.0 g / cc, 6.5 g / cc, 7.0 g / cc, 7.5 g / cc, 8.0 g / cc, 8.5 g / cc, 9.0 g / cc, 9.5 g / cc, 10.0 g / cc, 10.5 g / cc, 11.0 g / cc, 11.5 g / cc, 12.0 g / cc, 12.5 g / cc, 13.0 g / cc, 13.5 g / cc, 14.0 g / cc, 14.5 g / cc, 15.0 g / cc, 15.5 g / cc, 15.8 g / cc, 16.0 g / cc, 16.2 g / cc, 16.4 g / cc, 16.6 g / cc, 16.8 g / cc, 17.0 g / cc, 17.2 g / cc, 17.4 g / cc, 17.6 g / cc, 17.8 g / cc, 18.0 g / cc, 18.2 g / cc, 18.4 g / cc, 18.6 g / cc, 18.8 g / cc, 19.0 g / cc, 19.2 g / cc, 19.4 g / cc, or 19.6 g / cc.

[0132] With specific reference to FIG. 4, a vertical plane 1020 is illustrated to show hosel tilt relative to the club head body. The vertical plane 1020 is an imaginary plane that is generally perpendicular to a ground surface in response to the club head body 104 being at an address position. The vertical plane 1020 is tangent to a leading edge 133 (or forwardmost edge 133) of the club head 100 and perpendicular to a ground plane 160. The hosel axis 1055 is oriented at an angle relative to the vertical plane 1020. Stated another way, the hosel axis 1055 is oriented oblique to the vertical plane 1020. The hosel axis 1055 and the vertical plane 1020 define a first angle 1018. The first angle 1018 is representative of the hosel tilt. In the illustrated embodiment, the hosel tilt (or first angle 1018) is approximately 0.25 degrees to approximately 20 degrees, and more specifically approximately at least 5.0 degrees. The hosel tilt is oriented such that the hosel axis 1055 extends away from the vertical plane 1020. The hosel axis 1055 is configured to intersect the vertical plane 1020 at an imaginary position below the ground surface. This hosel tilt, or negative hosel tilt relative to the vertical plane 1020 allows the player to position their hands behind the ball (or towards a trailing or rear foot of the player) at the address position. It should be appreciated that at the address position, the club head body 104 is in contact with the ground. More specifically, the sole 115 (or a portion of the sole 115) is in contact with the ground.

[0133] With continued reference to FIG. 4, the club head 100 includes an impact force line 1035. The impact force line 1035 can be a force line that extends through a center of a golf ball when impacted by the strike face front surface 122. The impact force line 1035 can be perpendicular to the strike face 120, and more specifically perpendicular to the strike face front surface 122. In some embodiments, the impact force line 1035 can extend through the face center (FC) of the strike face front surface 122.

[0134] As noted above, bending the hosel 110 relative to the club head body 104 (via hammering and the like) adjusts the loft angle and the lie angle. The position and configuration of the hosel 110 and the hosel bore 150 spread the stress of the bending process over a longer length of the hosel 110, while also reducing the stress on other areas of the club head body 104. During bending, stress concentrates at the corners of the hosel bore proximal end 152. The hosel bore proximal end 152, as shown in FIGS. 1A & 5A, defines the lowest location of the hosel bore 150 on the hosel 110. By lowering the location of the hosel bore proximal end 152, the stress is spread over a broader wall and thereby reduces the maximum stress at any given location. However, the club head 100 maintains the ability to be adjusted for loft and lie up to ±4 degrees, ±2 degrees more than a traditional golf club head.II. Cavity-Back Golf Club Heads with Open Interior Cavity

[0135] As discussed above, extending the hosel bore into the club head body by a distance defined by the difference between the hosel bore height (HBH) and (HL) removes material and mass from the heel, thereby increasing discretionary mass. In some embodiments, discretionary mass can be further increased by eliminating the tip weight enabling a shorter hosel bore height (HBH). For embodiments that omit a tip weight, swing weighting can be accomplished by incorporating weight members into the rear of the club head. “Cavity-back” golf club heads, such as the golf club heads illustrated in FIGS. 16-37, can incorporate an insert that harbors a plurality of weight members for swing weighting, as discussed in further detail below.

[0136] A cavity-back golf club head, having an open interior cavity, is illustrated in FIGS. 16-27. The club head body 204 comprises a strike face 220, a top rail 214, a sole 215 opposite the top rail 214, a toe end 208, and a heel end 212 opposite the toe end 208. The strike face 220 further comprises a strike face rear surface 223 and a strike face front surface 222 opposite the strike face rear surface 223. The strike face 220 further comprises a strike face perimeter 205 which defines an outer boundary of the strike face 220.

[0137] The top rail 214, sole 215, toe end 208, and heel end 212 each extend rearwardly from the strike face perimeter 205. The sole 215 comprises a sole inner surface 217 which extends from the strike face perimeter 205 on the strike face rear surface 223 to the interior cavity opening perimeter 229. The interior cavity opening perimeter 229 is defined as the junction between the exterior surface 280 of the club head body 204 and the interior surface 281 of the club head body 204. The sole inner surface 217 defines an interior cavity base 276, and an interior surface of the top rail 214 defines an interior cavity top 277. The sole 215 further comprises a sole exterior surface 219, which extends from the leading edge 233 to the interior cavity opening perimeter 229. The club head body 204 further comprises a hosel 210 located proximate the heel end 212 and configured to receive a shaft.

[0138] As illustrated in FIGS. 26-27, the golf club head further comprises a coordinate system centered about the face center (FC). The coordinate system comprises an X-axis 2040, a Y-axis 2050, and a Z-axis 2060. The X-axis 2040 extends in a heel-to-toe direction. The X-axis 2040 is positive towards the heel end 212 and negative towards the toe end 208. The Y-axis 2050 extends in a sole-to-top rail direction and is orthogonal to the X-axis 2040. The Y-axis 2050 is positive towards the top rail and negative towards the sole. The Z-axis 2060 extends in a direction from a front end to a rear end of the golf club head. The Z axis 2060 is perpendicular to both the X-axis 2040 and the Y-axis 2050.

[0139] As illustrated in FIGS. 26-27, the golf club head comprises a coordinate system centered about the center of gravity (CG). The coordinate system comprises an X′-axis 2070, a Y′-axis 2080, and a Z′-axis 2090. The X′-axis 1070 extends in a heel-to-toe direction. The X′-axis 2070 is positive towards the heel end 212 and negative towards the toe end 208. The Y′-axis 2080 extends in a sole-to-top rail direction and is orthogonal to the X′-axis 2070. The Y′-axis 2080 is positive towards the top rail and negative towards the sole. The Z′-axis 2090 extends in a direction from a front end to a rear end of the golf club head. The Z′ axis 2090 is perpendicular to both the X′-axis 2070 and the Y′-axis 2080.1. Strike Face Geometry

[0140] The strike face geometry can be designed to improve ball speed and accommodate the insert, as discussed in further detail below. The strike face 220 can have a strike face thickness 240, measured from the strike face rear surface 223 to the strike face front surface 222 in a direction perpendicular to the loft plane 2022. In some embodiments, the strike face thickness 240 can vary in a top rail 214 to sole 215 direction and / or a heel end 212 to toe end 208 direction. For embodiments where the strike face thickness is variable, the strike face thickness 240 can include a maximum value (maximum strike face thickness) and a minimum value (minimum strike face thickness).

[0141] In some embodiments, the strike face 220 can comprise a strike face thickness between 0.050 and 0.150 inch. In some embodiments, the strike face thickness can be 0.050 and 0.058 inch, between 0.058 and 0.066 inch, between 0.066 and 0.074 inch, between 0.074 and 0.082 inch, between 0.082 and 0.090 inch, between 0.090 and 0.098 inch, between 0.098 and 0.106 inch, between 0.106 and 0.114 inch, between 0.114 and 0.122 inch, between 0.122 and 0.130 inch, between 0.130 and 0.138 inch, between 0.138 and 0.150 inch. The strike face thicknesses disclosed herein can apply to a maximum strike face thickness, a minimum strike face thickness, or any thickness located within the strike face perimeter.

[0142] In some embodiments, the strike face 220 can comprise a difference between the maximum strike face thickness and the minimum strike face thickness. In some embodiments the minimum strike face thickness can be between 80% and 95% of the maximum strike face thickness. In other embodiments the minimum strike face thickness can be between 25% and 30%, 30% and 35%, 35% and 40%, 40% and 45%, 45% and 50%, 50% and 55%, 55% and 60%, 60% and 65%, 65% and 70%, 70% and 75%, 75% and 80%, 80% and 85%, 85% and 90%, or 90% and 95% of the maximum strike face thickness.

[0143] The strike face 220 defines a face center (FC), which is the geometric centerpoint of the strike face perimeter, as illustrated in FIGS. 26 and 27. The face center (FC) has a face center height (HFC) defined as the distance between the face center (FC) and the ground plane 260 measured along the Y-axis 2050. The strike face 220 further comprises a plurality of grooves 225 extending in a heel end 212 to toe end 208 direction parallel to the ground plane 260. The strike face 220 can have a strike face perimeter 205. The strike face perimeter 205 is defined where the strike face front surface 222 deviates from the loft plane 2022 proximate the heel end 212, toe end 208, top rail 214, and sole 215. The strike face perimeter 205 includes at least an upper edge 241 and a leading edge 233. The upper edge 241 is the portion of the strike face perimeter 205 proximate the top rail and defines a transition from the strike face 220 to the top rail 214. The upper edge 241 defines a face apex (FA), located at the point along the upper edge 241, which is furthest from the face center along the Y-axis 2050. The leading edge 233 is the most soleward portion of the strike face perimeter and delineates a boundary between the strike face 220 and the sole 215. The leading edge 233 defines a face nadir (FN), located at the point along the leading edge 233 which is furthest from the face center along the Y-axis 2050. The strike face 220 defines a face height (HSF) defined as the distance between the face apex (FA) and the face nadir (FN) measured along the Y-axis 2050. The strike face 220 defines a face center width (WFC), defined as the distance between a heel end 212 of the strike face perimeter 205 and toe end 208 of the strike face perimeter 205 measured parallel to the loft plane 2022 at the face center height (HFC).

[0144] In some embodiments, the face height (HSF) can be between 1.5 and 2.2 inches. In some embodiments, the face height (HSF) can be between 1.5 and 1.8 inches, between 1.6 and 1.9 inches, between 1.7 and 2.0 inches, between 1.8 and 2.1 inches, between 1.9 and 2.2 inches, between 2.0 and 2.3 inches, or between 2.1 and 2.4 inches.

[0145] A shorter face height (HSF) lowers the face center (FC) closer to the ground plane 160. Lowering the face center (FC) can be advantageous for players who want to increase the launch angle of their golf ball. In some embodiments, the face center height (HFC) can be between 0.70 and 1.1 inches. In some embodiments, the face center height (HFC) can be between 0.7 and 0.8 inch, between 0.8 and 0.9 inch, between 0.9 and 1.0 inches, or between 1.0 and 1.1 inches.

[0146] In some embodiments, the face center width (WFC) can be between 2.5 and 3.5 inches. In some embodiments, the face center width (WFC) can be between 2.5 and 2.6 inches, between 2.6 and 2.7 inches, between 2.7 and 2.8 inches, between 2.8 and 2.9 inches, between 2.9 and 3.0 inches, between 3.0 and 3.1 inches, between 3.1 and 3.2 inches, between 3.2 and 3.3 inches, between 3.3 and 3.4 inches, or between 3.4 and 3.5 inches. The face center width (WFC) can be primarily influenced by the curvature of the strike face perimeter 205 proximate the toe end 208.2. Hosel Geometry

[0147] As discussed above, some embodiments of golf club heads according to the present disclosure have a weight system that eliminates the need for a “tip weight” in the hosel, which enables a shorter hosel and increases discretionary mass. Eliminating the tip weight reduces mass proximate the heel end 212, increases MOI, and improves sound (as will be discussed in greater detail below).

[0148] Referring to FIGS. 24 and 25, the club head body 204 comprises a hosel 210 proximate the heel end 212 and configured to receive a shaft. The hosel 210 comprises a hosel bore 150 defined by a hosel bore wall 258 extending downward along the hosel axis 2055 from an upper hosel ledge 251. The hosel 210 further comprises a hosel bore tip 255 defining a base of the hosel bore 250. The hosel 210 defines a hosel axis 2055 extending through a geometric center of the upper hosel ledge 251 and a geometric center of the hosel bore tip 255. The hosel 210 further defines a hosel bore height (HBH) measured between the upper hosel ledge 251 and the hosel bore tip 255 along the hosel axis 2055.

[0149] As discussed above, traditional club heads 400 typically comprise an extended hosel 410 which can accommodate a “tip weight.” In order to accommodate a “tip weight” traditional club heads 400 generally have a greater hosel bore height (HBH), as shown in FIG. 25. Traditional golf club heads, such as the one shown in FIG. 25 typically have a hosel bore height between 1.0 inch and 1.5 inches.

[0150] Removing R the “tip weight” allows the hosel 410 to be shortened. Golf club heads constructed according to the present disclosure can have a hosel 210 with a hosel bore height (HBH) between 0.675 inches and 1.250 inches, as shown in FIG. 24. In some embodiments, the hosel 210 can have a hosel bore height (HBH) between 0.675 and 0.725 inch, between 0.725 and 0.775 inch, between 0.775 and 0.825 inch, between 0.825 and 0.875 inch, between 0.875 and 0.925 inch, between 0.925 and 0.975 inch, between 0.975 inch and 1.025 inches, between 1.025 and 1.075 inches, between 1.075 and 1.125 inches, between 1.125 and 1.175 inches, between 1.175 and 1.225 inches, or between 1.225 and 1.250 inches. Traditional club heads can have a hosel bore height between 1.5 inches and 2.0 inches. Therefore, golf club heads constructed according to the present disclosure can have a hosel bore height (HBH) which is 16.67% to 66.25% shorter than traditional golf club heads.

[0151] Additionally, the aforementioned hosel geometries (hosel height, hosel length, and hosel bore height) enable the club head frequency ranges, discussed below. These golf club frequencies determine the golf club head sound (or acoustic) profile. Though inherently subjective, certain club head acoustic characteristics, described below, are regarded as favorable. Moreover, these favorable sound characteristics can be achieved by adjusting an overall length of the hosel. The overall hosel length is measured from the distal end 154 (or hosel bore distal end 154) to the ground plane 160 along the hosel axis 1055. In some embodiments, the overall hosel length ranges inclusively between 0.75 inches and 3.0 inches. In some embodiments, the overall hosel length ranges inclusively between 1.0 inches and 2.5 inches. In some embodiments, the overall hosel length can range between 0.75 inch and 1.0 inch, 1.0 inch and 1.25 inches, 1.25 inches and 1.50 inches, 1.50 inches and 1.75 inches, 1.75 inches and 2.0 inches, 2.0 inches and 2.25 inches, 2.25 inches and 2.50 inches, 2.50 inches and 2.75 inches, or 2.75 inches and 3.0 inches. In one exemplary embodiment, the overall hosel length is between 2.40 inches and 2.73 inches.

[0152] Hosel height (HH), hosel length (HL), and hosel bore height (HBH) can also influence the overall hosel length, thereby altering the club head frequency, as discussed in Example VII. In other words, the club head frequency, influenced by overall hosel length, can quantitatively describe the club head sound profile.

[0153] Golf club heads constructed according to the present disclosure are particularly categorized by the club head frequencies at the 9th and 10th modes. Moreover, the threshold frequencies, or minimum frequency levels, are analyzed in view of the particular club head type. Specifically, game improvement club heads and player-style club heads may comprise different threshold frequencies. Game improvement club heads generally feature a larger size, greater perimeter weighting, and more club head offset than player-style club heads, which tend to have a more compact size, blade-like shape, and less offset. Due to the size and shaping differences between the game improvement club heads and the player-style club heads, the desired frequency ranges between the two club heads vary.

[0154] Particularly, in one embodiment, generally relevant to a game improvement club head, the club head frequency can be greater than or equal to 4000 Hz at mode 9 and greater than or equal to 6000 Hz at mode 10. Preferably, the club head frequency can be greater than or equal to 4300 Hz at mode 9 and greater than or equal to 6300 Hz at mode 10. More preferably, the club head frequency can be greater than or equal to 4800 Hz at mode 9 and greater than or equal to 6700 Hz at mode 10. In another embodiment, generally relevant to a player-style club head, the club head frequency can be greater than or equal to 6000 Hz at mode 9 and greater than or equal to 8000 Hz at mode 10. More preferably, the club head frequency can be greater than or equal to 6300 Hz at mode 9 and greater than or equal to 8500 Hz at mode 10.III. Weight System

[0155] According to certain aspects of the present disclosure, a weight system is incorporated into an insert coupled to the club head, thereby to facilitate swing weighting of the club head. Unlike conventional club heads, club heads constructed according to this embodiment omit a “tip weight.” Described herein are various embodiments of an iron-type golf club head with high forgiveness, increased ball speed, and high launch. The iron-type golf club heads disclosed herein can comprise an interior cavity. Further, the iron-type golf club heads disclosed herein can comprise an insert which further comprises a weight system. The insert at least partially fills the interior cavity and accommodates one or more weight members to provide a weight system for swing weighting. The insert can comprise a coverage volume greater than 40% of an available volume of the interior cavity. The insert visually fills the cavity, creating the appearance of a hollow-body or capped-back club head. To enhance this hollow-body or capped-back look, the rear surface of the insert may be designed to complement the geometry of the club head rear.1. Interior Cavity

[0156] Referring to FIGS. 16-27, the club head defines an interior cavity. The rear 218 can extend only partially between the sole 215 and the top rail 214, forming an interior cavity 275 that fluidly communicates with the club head exterior. In many embodiments, the interior cavity 275 is bounded by the strike face rear surface 223, interior cavity base 276, interior cavity top 277, and interior cavity opening perimeter 329, or a combination thereof (see, for example FIG. 23). As illustrated in FIG. 22, the interior cavity 275 comprises an interior cavity opening perimeter 129. The interior cavity opening perimeter 129 provides access to the interior cavity 275 from the exterior of the club head and allows the club head body 204 to receive an insert 265, as discussed in further detail below.

[0157] The size and shape of the interior cavity 275 is at least partially defined by the shape of the strike face rear surface 223. As discussed above and illustrated in FIG. 23, the sole 215 extends upward from a sole exterior surface 219 at least partially towards the top rail 214. The sole 215 does not extend all the way to the top rail 214 and does not contact the top rail 214. Rather, the interior cavity opening perimeter 129 defines an opening into the interior cavity 175 such that at least a portion of the strike face rear surface 223 is exposed.2. Insert

[0158] In many embodiments, the iron-type golf club head comprises an insert 265 located within the interior cavity 275. The insert 265 comprises an insert front surface 266, an insert rear surface 267 opposite the insert front surface 266, and an insert perimeter wall 268. The insert 265 can be positioned within the interior cavity 275 and can be secured to and / or contact the strike face rear surface 223. Specifically, the insert rear surface 267 can be configured to be adhered, or otherwise mechanically coupled, directly to strike face rear surface 223. In many embodiments, the strike face rear surface 223 receives an adhesive member 247 which is coupled to the strike face rear surface 223. The adhesive member 247 then receives the insert 265 and secures the insert to the club head 200.

[0159] The insert 265 can have an insert thickness 269 which is measured between an insert front surface 266 and insert rear surface 267 in a direction perpendicular to the loft plane 1022. In some embodiments, the insert thickness 269 can vary in a top rail 214 to sole 215 direction and / or a heel end 212 to toe end 208 direction. An insert 265 with a varying insert thickness 269 can be designed such that thicker regions are positioned at frequent impact locations. Reinforcing frequent impact locations can enable the strike face 220 to have a corresponding decreased strike face thickness 140, thereby increasing face deflection at frequent impact locations and increasing ball speed without sacrificing durability. The insert 265 can be positioned within the interior cavity 275 such that the insert rear surface 267 is visible when looking at the club head from the rear. The insert rear surface 267 can further span or extend across at least a portion of the strike face rear surface 223 in a heel end 212 to toe end 208 direction.

[0160] In some embodiments, the insert can comprise an insert thickness 269 which is less than 1.0 inch. In other embodiments, the insert can comprise an insert thickness which is between 0.10 inch and 0.30 inch, 0.30 inch and 0.50 inch, 0.50 inch and 0.70 inch, 0.70 inch and 0, 90 inch, 0.90 inch and 1.10 inches, 1.10 inches and 1.30 inches, or between 1.30 inches and 1.50 inches.

[0161] The insert 265 at least partially fills the interior cavity 275. In many embodiments, the insert 265 substantially fills the entire volume of the interior cavity 275. In such embodiments, the insert 265 is complementarily shaped to the geometry of the interior cavity and the rear surface of the insert 265 is substantially flush with the interior cavity opening perimeter 229. In other embodiments, such as the embodiment illustrated in FIG. 23, the insert 265 may only partially fill the volume of the interior cavity, such that the insert rear surface is recessed within the interior cavity. In many embodiments, the insert 265 can fill between 40% and 100% of the volume of the interior cavity 275. In many embodiments, the insert 265 can fill a range varying inclusively between 40% and 45%, 45% and 50%, 50% and 55%, 55% and 60%, 60% and 65%, 65% and 70%, 70% and 75%, 75% and 80%, 80% and 85%, 85% and 90%, 90% and 95%, or between 95% and 100% of the volume of the interior cavity 275. In some embodiments, the insert 265 can fill approximately 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100% of the volume of the interior cavity 275. In some embodiments, the insert 265 can fill between 40% and 50%, 50% and 60%, 60% and 75%, 75% and 85%, 85% and 95%, 80% and 90%, 75% and 90%, or between 85% and 100% of the volume of the interior cavity 275.

[0162] Additionally, the insert 265 can have an insert rear surface 267 with a surface area of the insert rear surface which is approximately equal to the surface area of the strike face rear surface 223. A ratio between the surface area of the insert rear surface 267 and the surface area of the strike face rear surface 223 (hereafter “insert surface area ratio”) can be between 0.700 and 1.200. In some embodiments, the insert surface area ratio can be between 0.700 and 0.725, 0.725 and 0.750, 0.750 and 0.800, 0.800 and 0.850, 0.850 and 0.900, 0.900 and 0.950, 0.950 and 1.000, 1.000 and 1.050, 1.050 and 1.100, or between 1.100 and 1.200. In other embodiments the insert surface area ratio can be greater than 0.600, greater than 0.700, greater than 0.800, greater than 0.900, greater than 1.000, greater than 1.100, or greater than 1.200.

[0163] The insert 265 can be formed from a polymer or flexible material with a low shore durometer (i.e., soft material). The insert 265 can be formed from a polymer matrix. The polymeric matrix can comprise glass-filled elastomer, a stainless steel-filled elastomer, a tungsten-filled elastomer, a thermoplastic polyurethane (TPU) composite, a thermoplastic elastomer (TPE) composite, or any other elastomer matrix composite, a Kevlar® (aramid) fiber-reinforced polymer, a carbon-fiber reinforced polymer, rubber, ethylene-vinyl acetate foam, polymer-based foam, any combination of a suitable resin and a suitable reinforcing fiber, or any combination of the above materials. Soft or flexible insert materials can improve the feel and sound of the golf club head through impact.

[0164] In some embodiments, the insert 265 can be shaped to complement the geometry of the rear 218. As discussed above, the insert front surface 266 can be shaped to give the appearance of being flush with the rear 218, providing the appearance that the insert 265 encloses the interior cavity. However, the insert 265 is dimensioned such that there is fluid communication between the interior cavity 275 and the exterior surface 180 of the club head 200. In particular, there is a gap between the insert perimeter wall 268 and the interior cavity opening perimeter 229. As shown in FIG. 36B, a gap width (WG) is measured between the insert perimeter wall 268 and the interior cavity opening perimeter 229 in a direction perpendicular to the Z-Axis 1060. The gap width (WG) can vary about the interior cavity opening perimeter 229.

[0165] In some embodiments the insert 365 can further comprise a plurality of recesses 230 on the insert rear surface 367. The plurality of recesses on the insert rear surface 367 can aide with adhesion of the insert rear surface 367 to the strike face rear surface 323. Additionally, the plurality of recesses on the insert rear surface 367 can decrease the mass of the insert 365, freeing up club head 300 mass which can be utilized elsewhere.

[0166] In some embodiments, the club head 200 can have a variable gap width (WG) which varies between 0.01 inch and 0.05 inch about the interior cavity opening perimeter 229. In other embodiments, the club head 200 can have a variable gap width (WG) about the interior cavity opening perimeter 229 which is between 0.005 and 0.025 inch, 0.025 inch and 0.075 inch, 0.075 inch and 0.125 inch, 0.010 and 0.025 inch, 0.020 and 0.080 inch, 0.035 and 0.075 inch, 0.010 and 0.100 inch, or between 0.025 and 0.060 inch.

[0167] In other embodiments, the club head 200 can have a constant gap width (WG) which is constant about the interior cavity opening perimeter 229. In some embodiments, the gap width (WG) can a constant value about the interior cavity opening perimeter 229 which is less than 0.0010 inch, 0.0015 inch, 0.0020 inch, 0.0025 inch, 0.0030 inch, 0.0035 inch, 0.0040 inch, 0.0045 inch, 0.0050 inch, 0.0055 inch, 0.0060 inch, 0.0065 inch, 0.0070 inch, 0.0075 inch, 0.0080 inch, 0.0085 inch, 0.0090 inch, 0.0095 inch, 0.0100 inch, 0.0105 inch, 0.0110 inch, 0.0115 inch, 0.0120 inch, 0.0125 inch, 0.0130 inch, 0.0135 inch, 0.0140 inch, 0.0145 inch, 0.0150 inch, 0.0155 inch, 0.0160 inch, 0.0165 inch, 0.0170 inch, 0.0175 inch, 0.0180 inch, 0.0185 inch, 0.0190 inch, 0.0195 inch, 0.0200 inch, 0.0205 inch, 0.0210 inch, 0.0215 inch, 0.0220 inch, 0.0225 inch, 0.0230 inch, 0.0235 inch, 0.0240 inch, 0.0245 inch, or less than 0.0250 inch. In some embodiments, the gap width (WG) can a constant value about the interior cavity opening perimeter 229 which is greater than 0.0010 inch, 0.0015 inch, 0.0020 inch, 0.0025 inch, 0.0030 inch, 0.0035 inch, 0.0040 inch, 0.0045 inch, 0.0050 inch, 0.0055 inch, 0.0060 inch, 0.0065 inch, 0.0070 inch, 0.0075 inch, 0.0080 inch, 0.0085 inch, 0.0090 inch, 0.0095 inch, 0.0100 inch, 0.0105 inch, 0.0110 inch, 0.0115 inch, 0.0120 inch, 0.0125 inch, 0.0130 inch, 0.0135 inch, 0.0140 inch, 0.0145 inch, 0.0150 inch, 0.0155 inch, 0.0160 inch, 0.0165 inch, 0.0170 inch, 0.0175 inch, 0.0180 inch, 0.0185 inch, 0.0190 inch, 0.0195 inch, 0.0200 inch, 0.0205 inch, 0.0210 inch, 0.0215 inch, 0.0220 inch, 0.0225 inch, 0.0230 inch, 0.0235 inch, 0.0240 inch, 0.0245 inch, or greater than 0.0250 inch.3. Weight Members

[0168] In many embodiments, such as the embodiment illustrated by FIG. 20, the insert 265 can comprise a plurality of weight members 270. In one embodiment, such as the embodiment illustrated in FIG. 20, the insert 265 comprises a first weight member 271 and a second weight member 272. In other embodiments, the plurality of weight members 270 can comprise only a first weight member 271. Further, the plurality of weight members 270 can be located at any portion(s) of the insert 265. In a preferred embodiment, the weight members can be located in the insert 265 at locations proximate the strike face perimeter 205. One exemplary embodiment, shown in FIG. 20, comprises a first weight member 271 proximal the toe end 208 and the sole 215 and a second weight member 272 proximate the toe end 208 and the top rail 214.

[0169] In many embodiments, the plurality of weight members 270 may be configured to be attached to a plurality of apertures 285 located on the insert front surface 266. In some embodiments, the plurality of weight members 270 are removably coupled to the insert 265, such as by mating threads in the weight members 270 and the plurality of apertures 285 of the insert 265. In other embodiments, the plurality of weight members 270 can be permanently or semi-permanently affixed to the plurality of apertures 285 of the insert 265. In particular, the plurality of weight members 270 can be attached to the insert 265 through any suitable means such as: usage of a snap-fit mechanism, interlocking methods, adhesives, or other means of mechanical coupling.

[0170] In many embodiments, each weight member of the plurality of weight members 270 can be shaped to sit flush with the insert rear surface 267 when residing within an aperture of the plurality of apertures 285. For example, the first weight member 271 can be shaped to sit flush within a first aperture 236 and the second weight member 272 can be shaped to sit flush within a second aperture 237.

[0171] Each weight member of the plurality of weight members 270 can be interchangeable with a group of weight members having a similar size and shape, but varying in mass. The ability to interchange removable weight members allows for easy swing weight adjustment. For example, a plurality of weight members may include a first weight member which is chosen from a group of first weight members of varying mass and a second weight member which is selected from a group of second weight members of varying mass. In another example a plurality of weight members may include a first weight member with a predetermined mass (hereafter a “fixed mass weight member”) and a second weight member selected from a group of second weight members having a varying mass (hereafter a “variable mass weight member”). In some embodiments, one or more of the apertures 285 do not receive a weight member 220.

[0172] The plurality of weight members can comprise a high-density material with a density greater than that of the club head body. In many embodiments, the plurality of weight members can be formed of tungsten or a tungsten alloy such as a tungsten-nickel alloy, tungsten-carbide alloy, tungsten-iron alloy, or a similar suitable material. In many embodiments, the plurality of weight members can be formed of a material which has a specific gravity ranging between 10 and 30. The plurality of weight members can be formed of a material which has a specific gravity between 10 and 12, 12 and 14, 14 and 16, 16 and 18, 18 and 20, 20 and 22, 22 and 24, 24 and 26, 26 and 28, or 28 and 30. For example, the plurality of weight members can have a specific gravity of 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30.

[0173] To allow for adequate adjustability of swing weight it is important that there is a significant variation in mass between 1) a plurality of weight members wherein each weight member is selected from a group of weight members to be the weight members with the lowest mass (hereafter “the lightest weight member build mass” or “lightest WMBM”) and 2) a plurality of weight members wherein each weight member is selected from a group of weight members to be the weight members with the greatest mass (hereafter “the heaviest weight member build mass” or “heaviest WMBM”). In general, a difference of 10 grams between the lightest weight member build mass and heaviest weight member build mass is sufficient to allow for adjustability of swing weight. In some embodiments the difference in mass between the lightest WMBM and heaviest WMBM (hereafter “build mass adjustability”) can be between 8 grams and 30 grams. The plurality of weight members described herein can allow for a build mass adjustability of between 8 and 10, 10 and 12, 12 and 14, 14 and 16, 16 and 20, 20 and 24, 24 and 26, 26 and 28, or 28 and 30 grams.

[0174] A sufficient build mass adjustability can be accomplished without the need for each weight member of the plurality of weight members to be a variable mass weight member. For example, a plurality of weight members comprising a first weight member selected from a group of first weight members having a mass of 5-15 grams and a second weight member which always has a mass of 2 grams provides for 10 grams of build mass adjustability. There are situations where including fixed mass weight members is advantageous for tuning key performance characteristics, as described below.

[0175] Key performance characteristics can be selectively tuned by including fixed mass weight members in the plurality of weight members. Cavity-back irons are designed for golfers who typically struggle to achieve a high enough launch angle at impact. This typically includes golfers with “slow” swing speeds (i.e. a 7-iron swing speed of less than 70 mph). To solve this problem, it is generally desirous to lower the club head CG to thereby increase launch angle. A first exemplary club head incorporating fixed mass weight members can be constructed to 1) lower CG across all club head build masses, 2) increase MOI and thereby increase forgiveness, and 3) provide adequate build mass adjustability for swing weighting.

[0176] The first exemplary club head can comprise a plurality of weight members including a first weight member located proximate the sole and a second weight member located proximate the top rail and the toe end. The first weight member can be a fixed mass weight member having a large mass. The second weight member can be a variable weight member wherein every second weight member of the group of second weight members has a mass less than that of the first weight member. The first weight member of the first exemplary club head can place a large amount of mass near the sole thereby lowering CG while increasing MOI of the club head. The second weight member of the first exemplary club head can place a relatively small amount of mass near the top rail, thereby minimizing the CG height contribution of the second weight member. Furthermore, placing the second weight member near the top rail can aid in increasing perimeter weighting of the club head, thereby increasing club head MOI. Accordingly, the first exemplary club head is that the lightest WMBM will have the lowest CG height and the CG height will increase as build mass increases. This correlation is advantageous since low swing speed golfers tend to struggle the most with low launch angle and also tend to require the lightest WMBM. Thereby, the first exemplary club head is an illustrative example of how key performance characteristics can be selectively tuned using the adjustable mass insert of the present invention.

[0177] In another exemplary embodiment, a club head 500 comprises a shortened hosel bore and a weighted badge to produce a low center of gravity and increase club head MOI to improve launch and spin characteristics, as illustrated in FIGS. 47-49. The weighted badge also enables swing-weighting of the club head to fit different golfers swings. The badge further reduces vibrational response in the club head by contacting the rear surface of the strike face and a top surface of the sole bar to improve sound at impact. In this embodiment, the club head further comprises a locating feature to improve badge alignment and retention.

[0178] As illustrated in FIGS. 47-49, the club head 500 comprises a strike face, a toe end 508, a heel end 512, a hosel 510, a top rail 514, a sole 515, a rear cavity 518, and a badge 565 having a weight 570. The hosel 510 has a shortened hosel bore, as described above, that lowers the center of gravity while still providing loft and lie adjustability. The club head 500 further comprises a sole bar 580 having a sole bar top surface 581, a sole bar heel surface 582, and a sole bar toe surface 583. The sole bar top surface 581 has a locating feature 590 that improves badge alignment and retention. In this embodiment, the locating feature 590 is an elongated recess with rounded ends forming a blind hole in the sole bar top surface 581. In other embodiments, such as in a club head 600 illustrated in FIG. 50, the locating features 690 are at least two circular bores. In other embodiments, the locating features 590, 690 can have any size, shape, or number to increase badge alignment and retention as needed.

[0179] In the illustrated embodiment in FIG. 49, the badge 565 is coupled to the club head 500 by an adhesive member 547. The adhesive member 547 contacts the sole bar top surface 581 and the strike face rear surface to increase badge retention and dampen vibrations. The badge 565 contacts the strike face rear surface above the adhesive member 547.

[0180] The badge 565 comprises complementary geometry to the locating feature 590. In this embodiment, the badge 565 comprises a protrusion 591 located on the bottom of the badge that is shaped similarly to the locating feature 590. The protrusion 591 fits within and is surrounded by the locating feature 590. The protrusion 591 cannot be seen from an exterior view of the club head.

[0181] The badge 565 has a volume between 1.0 and 6.0 cc. For example, the badge 565 can have a volume between 1.0 and 4.0 ccs, 2.0 and 5.0 ccs, or between 3.0 and 6.0 ccs. In some embodiments, the badge has a volume of about 1.0 cc, 1.5 ccs, 2.0 ccs, 2.5 ccs, 3.0 ccs, 3.5 ccs, 4.0 ccs, 4.5 ccs, 5.0 ccs, 5.5 ccs, or 6.0 ccs.

[0182] The badge 565 has a length, measured from a heel most point to a toe most point between 1.75 and 3.0 inches. For example, the badge 565 can have length between 1.75 inches and 3.0 inches, each 0.5 inches wide, are: 1.75 and 2.25 inches, 2.00 and 2.50 inches, 2.25 and 2.75 inches, or between 2.50 and 3.00 inches.

[0183] The badge 565 has a height, measured from a topmost point to a bottom most point between 0.350 and 0.525 inches. For example, the badge 565 can have a height between 0.350 and 0.400 inches, 0.375 and 0.425 inches, 0.400 and 0.450 inches, 0.425 and 0.475 inches, 0.450 and 0.500 inches, or between 0.475 and 0.525 inches.

[0184] The badge 565 has a depth, measured from a front to back direction between 0.45 and 0.70 inch. For example, the badge 565 can have a depth between 0.450 and 0.500 inches, 0.475 and 0.525 inches, 0.500 and 0.550 inches, 0.525 and 0.575 inches, 0.550 and 0.600 inches, 0.575 and 0.625 inches, 0.600 and 0.650 inches, 0.625 and 0.675 inches, or between 0.650 and 0.700 inches.

[0185] The badge 565 has a badge top surface 566 and a badge rear surface 567 to form the exterior, or visible, surfaces of the badge 565. In some embodiments, the badge rear surface 567 can be continuous with a sole bar rear surface. In other embodiments, the badge rear surface 567 can be offset inwardly from the sole bar rear face. The badge 567 further comprises angled ends in the heel and toe that are complementary to the sole bar heel surface 582 and the sole bar toe surface 583. The badge top surface 566 and the badge rear surface 567 are planar to improve the overall aesthetic of the club head. In other embodiments, the badge 567 can have non-planar surfaces, or other number of exterior surfaces to achieve a desired aesthetic. In the illustrated embodiment, the weight 570 is positioned within the badge top surface 566.

[0186] In other embodiments, the weight 570 may be positioned in other location on the badge such as the badge rear surface 567, or on the badge bottom surface. The badge weight 570 comprises a badge weight density that is greater than a badge density. The higher density of the badge weight allows the badge 565 to be used for swing weighting purposes during club head assembly.

[0187] The badge weight 570 can have a mass between 0.5 grams and 10 grams. For example, the badge weight 570 can have a mass between 0.5 and 1.0 grams, 1.0 and 1.5 grams, 1.5 and 2.0 grams, 2.0 and 2.5 grams, 2.5 and 3.0 grams, 3.0 and 3.5 grams, 3.5 and 4.0 grams, 4.0 and 4.5 grams, 4.5 and 5.0 grams, 5.0 and 5.5 grams, 5.5 and 6.0 grams, 6.0 and 6.5 grams, 6.5 and 7.0 grams, 7.0 and 7.5 grams, 7.5 and 8.0 grams, 8.0 and 8.5 grams, 8.5 and 9.0 grams, 9.0 and 9.5 grams, or between 9.5 and 10.0 grams. In other embodiments, the badge weight 570 can have a mass between 0.5 and 3.5 grams, 2.0 and 5.0 grams, 3.5 and 6.5 grams, 5.0 and 8.0 grams, or between 7.0 and 10.0 grams.

[0188] The badge weight 570 can have a volume between 0.25 cc and 7.5 cc. For example, the badge weight 570 can have a volume between 0.25 and 2.25 ccs, 1.25 and 3.25 ccs, 2.25 and 4.25 ccs, 3.25 and 5.25 ccs, 4.25 and 6.25 ccs, or between 5.0 and 7.0 ccs.

[0189] The badge weight 570 can be adhesively attached, integrally attached such as by co-molding, or mechanically attached to the badge 565. The badge weight 570 can also have other shapes or geometries as desired to achieve a desired mass properties such as lowered center of gravity or higher MOI. For example, in one embodiment, the badge 570 can have two weights positioned on a heel end and toe end of the badge to improve the MOI of the club head while enabling swing-weighting of the club head.

[0190] In another embodiment, a club head 700 can comprise an insert 765 with a weighted cap 770 that is positioned within a rear cavity in the club head to improve badge retention and vibrational response, as illustrated in FIG. 51. In this embodiment, the club head 700 is similar club heads 500 and 600 described above, in that the club head 700 has a lowered hosel bore that is used in combination an insert 765 to lower the center of gravity and increase the MOI of the club head. The club head 700 is different than the embodiments 500 and 600 above in that the club head 700 has a rear cavity that houses the insert instead of having locating features. The rear cavity has a rear cavity front wall 731, a rear cavity bottom wall 732, and a rear cavity rear wall 733 that define the rear cavity. The insert 765 is adhesively attached to the rear cavity front wall 731, the rear cavity bottom wall 732, and the rear cavity rear wall 733. The insert 765 comprises a weighted cap 770 that covers the insert 765. The weighted cap 770 is similar to the badge weight 570 described above in that the weighted cap 770 is used for swing weighting purposes.

[0191] The weighted cap 770 has a mass between 1 and 15 grams. For example, the weighted cap 770 can have a mass between 1.0 and 4.0 grams, 2.5 and 5.5 grams, 4.0 and 7.0 grams, 5.5 and 8.5 grams, 7.0 and 10.0 grams, 8.5 and 11.5 grams, 10.0 and 13.0 grams, 11.5 and 14.5 grams, or between 12.0 and 15.0 grams.4. Additional Features

[0192] The club heads described herein can comprise additional features which complement the weight systems described herein. The additional features described herein can be used in any combination and in conjunction with any of the embodiments described herein.A. Strut

[0193] In some embodiments, such as the embodiment of FIGS. 28-37 the club head body 304 can comprise one or more struts 334. The strut 334 can serve to reinforce the club head body and provides a structure for the insert 365 to abut. For a detailed description of a strut 334, see U.S. Pat. No. 9,517,393, which is incorporated herein by reference. The strut 334 can extend between two non-adjacent portions of the interior cavity opening perimeter 328. In some embodiments, the strut can extend between the interior cavity opening perimeter 328 proximate the top rail 310 and the interior cavity opening perimeter 328 proximate the sole 315. In some embodiments, the strut can extend between the interior cavity opening perimeter 328 proximate the heel end 312 and the interior cavity opening perimeter 328 proximate the toe end 308. The strut 334 may be formed as a bar, beam, channel, or rod. The one or more struts 334 can complement geometry on the insert rear surface 367 to aide in securing the insert 365 to the club head body 301. The strut can have a strut front surface 348 and strut perimeter walls 349 on either side of the strut front surface 348. The strut 334 can define a strut longitudinal axis 3095 extending through a geometric center of the strut and in a direction perpendicular to the Z-axis 3060. The strut longitudinal axis3095 can define a strut angle 1006 defined between the strut longitudinal axis 3095 and the ground plane 360, as shown in FIG. 37. The strut can define a strut width (WS), measured between the strut perimeter walls 349 in a direction perpendicular to the strut longitudinal axis.

[0194] In some embodiments the strut angle 1006 can be between 15 degrees and 165 degrees. In other embodiments the strut angle 1006 can be between 15 degrees and 30 degrees, 30 degrees and 45 degrees, 45 degrees and 60 degrees, 60 degrees and 75 degrees, 75 degrees and 90 degrees, 90 degrees and 105 degrees, 105 degrees and 120 degrees, 120 degrees and 135 degrees, 135 degrees and 150 degrees, or between 150 degrees and 165 degrees.

[0195] In some embodiments, the strut width (WS) can be 0.25 inches. In other embodiments, the strut width (WS) can be between 0.10 inch and 0.60 inch. In other embodiments, the strut width (WS) can be between 0.10 inch and 0.15 inch, 0.15 inch and 0.20 inch, 0.20 inch and 0.25 inch, 0.25 inch and 0.30 inch, 0.30 inch and 0.35 inch, 0.35 inch and 0.40 inch, 0.40 inch and 0.45 inch, or between 0.45 inch and 0.50 inch. In other embodiments the strut width (WS) can be greater than 0.10 inch, 0.15 inch or greater than 0.20 inch. In other embodiments the strut width (WS) can be less than 0.60 inch, 0.55 inch or less than 0.50 inch. The strut width (WS) is a partial determinate of the reinforcement the strut provides and can be selected to control the hinge effect of the club head at impact.

[0196] In some embodiments, the insert 365 can comprise an insert undercut 331 which compliments the geometry of the strut 334. The insert undercut can have an insert undercut width (WIU), measured between the insert undercut perimeter walls 332, which is equal to or less than the strut width (WS). In some embodiments, the insert undercut width (WIU) can be 0.25 inches. In other embodiments, the insert undercut width (WIU) can be between 0.10 inch and 0.15 inch, 0.15 inch and 0.20 inch, 0.20 inch and 0.25 inch, 0.25 inch and 0.30 inch, 0.30 inch and 0.35 inch, 0.35 inch and 0.40 inch, 0.40 inch and 0.45 inch, or between 0.45 inch and 0.50 inch. In other embodiments the insert undercut width (WIU) can be greater than 0.10 inch, 0.15 inch or greater than 0.20 inch. In other embodiments the insert undercut width (WIU) can be less than 0.60 inch, 0.55 inch or less than 0.50 inch.

[0197] To further aide in securing the insert 365, the strut 334 can comprise complementary receiving geometry to the insert 365. In some embodiments, the insert 365 can comprise posts or pegs which are received by corresponding through-holes on the strut 334. In other embodiments the strut 334 and the insert 365 can both comprise through-holes which receive a separately formed screw, peg, post, or similar securing apparatus for securing the strut 334 to the insert 365.B. Mass Pads

[0198] In some embodiments, the club head can comprise a mass pad formed as an integral part of the club head body. In other embodiments, all or a portion of the mass pad can be separately formed and attached to the sole. The weight members disclosed herein may comprise a similar or different material than the body material. In some embodiments, the mass pad can comprise a higher density material than the body material to concentrate mass in a desired location. The club head 300 can form a mass pad 385 located in a low and rearward portion of the interior cavity 375, proximate both the sole 315 and the rear 318. The mass pad 385 comprises a mass pad front surface 359 disposed toward the strike face 320 but spaced rearward from the strike face rear surface 323, such that the mass pad front surface 359 does not contact the strike face 320.

[0199] The mass pad 385 can define a mass pad depth (DMP). The mass pad depth (DMP) assists in dictating club head CG and mass properties. The mass pad 385 defines a mass pad depth (DMP) measured between the strike face rear surface 323 and the mass pad front surface 259. In some embodiments, the mass pad depth (DMP) is variable. In such embodiments, the mass pad depth (DMP) is smallest proximate the sole and increases in a top-rail direction. This configuration creates a mass buildup soleward from Face center (FC), causing the club head CG to be lower. Lowering the CG improves ball speeds and launch characteristics. In other embodiments, the mass pad depth (DMP) can be substantially constant.I. EXAMPLESExample I—Comparison of Mass Properties Between One Embodiment of Club Head Described Herein And Control Club Head

[0200] Example I provides a comparison between two embodiments of a traditional iron-type golf club head with typical hosel bore geometry and length, one having an external notch and the other with no notch, and a separate embodiment of a club head with the hosel bore geometry described herein with no external notch. More specifically, Example 1 discusses differences in CG and MOI between two traditional club heads and one embodiment of the club head with the low hosel geometry described above, as shown in Table 1.

[0201] As shown in FIG. 6A, the two traditional iron-type golf club head comprising a typical hosel geometry and a hosel notch (hereafter referred to as “Control Club Head 1” and “Control Club Head 2”). Also described herein is an exemplary embodiment having an iron-type golf club head without a notch, a shorter hosel bore geometry and wall tapering as described above. Control Club Head 1 comprises the same external structure as Exemplary Club Head 1.

[0202] Control Club Head 1 and Exemplary Club Head 1 comprise similar body structure, volume, and loft angle. A direct comparison highlighting differences in hosel dimensions, CG, MOI, and club head mass can be seen below in Table 1.TABLE IClub Head Dimensions in Control Heads 1 & 2 vs. Exemplary Club Head Control Club Control Club Exemplary Head 1 Head 2 Club Head 1Club head mass (g) 255 260 255 Total hosel volume 0.172 0.135 0.190 (in3)Hosel volume above 0.172 0.135 0.171 midplane (in3) Hosel volume above 0.172 0.135 0.150 hosel-body meeting point (in3) Ground plane to 0.896 0.917 0.896 hosel-body meeting point (in) Ground plane to 0.706 0.695 0.706 midline axis (in) Ground plane to 0.927 1.137 0.397 bottom of hosel bore (in)Ground plane to top 2.335 2.340 2.135 of hosel (in) CGx (in) 0.082 −0.002 −0.025 Cgy (in) 0.524 0.538 0.486 MOIxx (g / in2) 98.5 83.5 89.4 MOIyy (g / in2) 374.7 321.4 356.1 MOIzz (g / in2) 429.1 367.3 403.1 Inner bore diameter 0.355 0.353 0.153 at bottom hosel (in) Inner bore diameter 0.408 0.408 0.408 at top hosel (in) Outer hosel diameter 0.540 0.520 0.540 at top hosel (in) Wall thickness 0.077 0.0568 0.077 (range if applicable) average at mid hosel cross section (in) Wall thickness 0.066 0.052 0.066 (range if applicable) constant average constant at upper hosel cross section (in)

[0203] As shown in Table 1, the club head body of Exemplary Club Head 1 is very similar to the bodies of Control Club Head 1 and Control Club Head 2. A distance between the ground plane and a point where the external hosel meets the top rail is the same between Exemplary Club Head 1 and Control Club Head 1, and similar in Control Club Head 2. Additionally, a distance between the ground plane and the mid-line axis is the same between Exemplary Club Head 1 and Control Club Head 1, and similar in Control Club Head 2. Furthermore, hosel wall thicknesses in both an upper region and a middle region of the hosel are the same between Exemplary Club Head 1 and Control Club Head 1 and are similar in Control Club Head 2.

[0204] Table I shows that Exemplary Club Head 1 comprises a hosel bore volume that is 10.5% greater than that of Control Club Head 1, and 40.7% greater than that of Control Club Head 2. An increase in hosel bore volume correlates with an increased extension of the hosel bore into the club head body, thereby creating discretionary weight and lowering the club head center of gravity. Moreover, the entirety of the hosel bore volume for both Control Club Head 1 and Control Club Head 2 are located above the midline axis, while only 90% of the hosel bore volume of Exemplary Club Head 1 is positioned above the midline axis, with the surplus volume extending below the midline axis and further into the club head. The hosel bore volume positioned below the midline axis further highlights a deeper hosel bore design, which in turn enhances club head CG and mass properties.

[0205] While the hosel bore volume of Exemplary Club Head 1 (0.190 in.3) is greater than both Control Club Head 1 (0.172 in.3) and Control Club Head 2 (0.135 in.3), the external hosel height of Exemplary Club Head 1 (2.135 in.), from the ground plane, is substantially lower than that of Control Club Head 1 (2.335 in.) and Control Club Head 2 (2.340 in.). Specifically, the external hosel height of Exemplary Club Head 1 is 8.6% lower than the hosel of Control Club Head 1, and 8.8% lower than the hosel of Control Club Head 2.

[0206] A distance between the ground plane and the bottom of the hosel bore is much lower in Exemplary Club Head 1, when compared with Control Club Head 1 and Control Club Head 2. Specifically, the height of the Exemplary Club Head 1 hosel bore lower edge from the ground plane is 57.1% lower than Control Club Head 1 and 65.1% lower than Control Club Head 2. This comparison highlights the extent of lengthening which the hosel bore of Exemplary Club Head 1 exhibits. Specifically, the external hosel of Exemplary Club Head 1 is only 8.6%-8.8% lower than Control Club Head 1 and Control Club Head 2, while the internal hosel bore extends much lower, such that its lower edge is 57.1%-65.1% lower than Control Club Head 1 and Control Club Head 2. As mentioned above, the lengthening or extension of the hosel bore lowers club head CG, thereby improving mass properties and club head performance.

[0207] The extended hosel bore of Exemplary Club Head 1 resulted in less material positioned in the heel side of the club head, which increased discretionary mass for strategic placement elsewhere within the club head. As shown in Table 1, the club head mass of Exemplary Club Head 1 was the same as that of Control Club Head 1, and 5 g less than Control Club Head 2. The mass positioned in the heel side of the club head was reduced in the exemplary club head. It was repositioned elsewhere causing the CG to shift both toward the toe and downward. Exemplary Club Head 1 shows a downward shift in CG of 0.038 inch, when compared with Control Club Head 1, or 0.052 inch, when compared with Control Club Head 2. Exemplary Club Head 1 shows a toeward shift in CG of 0.107 inch, when compared with Control Club Head 1, or 0.023 inch, when compared with Control Club Head 2. Moving the club head CG toward the toe offsets the weight of the hosel, thereby aligning the club head CG with the sweet spot. This mass distribution increases club head forgiveness and improves ball speed and launch angle.

[0208] Applicant further noted that MOI of Exemplary Club Head 1 remained in a range comparable to both Control Club Head 1 and Control Club Head 2. Specifically, Exemplary Club Head 1 showed a decrease in MOI in all three of the x, y, and z directions, relative to Control Club Head 1, and an increase in MOI in all three of the x, y, and z directions, relative to Control Club Head 2. The decrease in MOI relative to Control Club Head 1 results from removing mass in the far heel side of the club head. While a higher MOI is generally desirable, it has been found that player performance can be benefited more by a downward shift in CG than an increase in MOI. Specifically, testing shows that performance characteristics including stat area and accuracy can be maintained or improved by a shift in CG, even in cases where MOI is reduced. Therefore, maintaining MOI, while moving CG lower, results in overall performance benefits.Example II—Comparison of Material Deformation From Bending Between One Embodiment of Club Head Described Herein and Control Club Head

[0209] Example II provides a comparison illustrating the effect of a lowered, or lengthened, hosel bore on ability to bend and development of highly visible surface deformation resulting from stress. Specifically, Example II compares one embodiment of the club head described herein, comprising an extended hosel bore lacking an external notch, and one embodiment of a traditional iron-type golf club head, comprising typical hosel bore geometry having an external notch.

[0210] The standard club (hereafter referred to as the “Control Club Head”) comprised a body having a heel, toe, upper portion, and a lower portion, a hosel, a hosel bore configured to connect the golf club head with a shaft, and a notch located below the hosel on the heel side of the body. The Exemplary club (hereafter referred to as the “Exemplary Club Head”) comprised a bore extending lower into the body and shortened hosel relative to the standard club. The Exemplary Club Head also omitted any notch or cutout feature on the heel or surrounding area. All elements, dimensions, and features were the same throughout both club heads.

[0211] When a club head hosel is forcibly bent following manufacturing, the applied force may produce visible marks at the bend site due to material deformation. The amount of material surface deformation was analyzed and recorded on a qualitative feedback scale between an exemplary club and a standard club. A plurality of clubs were forcibly bent at the hosel to a degree ranging between 2° and 4° from neutral, starting position. If a club head was not able to be bent to the desired degree without visible surface deformation (i.e. stress marks), the head received a “−” score. If the club head was able to be bent to the desired degree without significant surface deformation, the club head received a “+” score. The exemplary club head and the standard club head were both measured in this way for upright and flattened lie adjustments as well as open and closed loft adjustments. Table II below details the degree of bending attempted and resultant surface deformation rating.TABLE IIDegree of bending and resultant demarcation rating in a standard club head vs. an exemplary club head Exemplary club head Standard Club Head Surface Surface Deformation Deformation Club no. Degree bent Rating Degree bent Rating1 3.04 +3.87 −2 5.43 +5.01 −3 −4.65 +−4.23 −4 −5.44 +−5.35 +

[0212] Table II illustrates a sample trial between four Exemplary and Standard Club Heads, comparing degree of bending and resultant deformation ratings. Visible deformation marks or discoloration resulting from the forced bending were assessed using the scale described above. Minor variance in degree bent is due to human error within the bending process and is overall negligible, as the bending of the lie angle on a post-manufactured club head can be imprecise. As shown in Table II, the Exemplary Club Head was able to be bent to a similar degree as the Control Club Head. However, the Control Club Head visibly deformed as a result of bending in three out of four samples tested. The Exemplary Club Head remained visibly unaffected by the applied force, while maintaining the ability to be successfully bent to desirable degrees.Example III—Comparison of FEA Response to Applied Forces at Hosel

[0213] This example provides a qualitative comparison illustrating the effect of a lowered, or lengthened, hosel bore on concentration of stress. Specifically, Example III provides a comparison of stress dispersion based on surface area of one embodiment of the club head described herein, comprising a lowered hosel bore and omitting an external notch, and one embodiment of a traditional iron-type golf club head comprising typical hosel bore geometry and having an external notch.

[0214] Stress values at a site of bending for a standard golf club head were compared to those of an exemplary golf club head. The standard golf club head (hereafter referred to as the “Control Club Head”) comprised a crown, sole, face, rear, hosel, and hosel bore. The exemplary golf club head (hereafter referred to as the “Exemplary Club Head”) comprised similar features with a shortened hosel and lowered hosel bore compared to the standard club. With the exception of the hosel, hosel bore, and notch, all dimensions and features between the golf club heads were the same throughout the golf club body.

[0215] Analysis of each club head's response to constant applied bending forces is shown in FIGS. 5B-5D (Exemplary Club Head) and 6B-6D (Control Club Head). Illustrated stresses along the hosel indicate the occurrence of bending in response to the forces applied. In the referenced figures, high amounts of stress are denoted by red coloration, while low amounts of stress are denoted by dark blue coloration. Colors ranging from red to dark blue, such as orange, yellow, green, and light blue denote decreasing amounts of stress in this respective order. The scale of stress in FIGS. 5B-5D and in 6B-6D is equal across both models (i.e., the value of stress in a red area illustrated in FIG. 5B is of equal value to a red area illustrated in FIG. 6B). The colors within these figures illustrate the distribution of stresses across the hosel in both club heads analysed at comparable values.

[0216] It is beneficial for the stressed to be dispersed across the hosel, rather than concentrated at any given site. Areas with higher stress than the surrounding region will often produce visible material surface deformation on the hosel. A club head with high stress across the hosel, but not at any discernably concentrated site, will typically bend without generating such stress marks. This is preferred, as visible surface deformation is not only unsightly, but can also compromise the structural integrity of the hosel at that site.

[0217] As illustrated in FIGS. 5B-5D, the Exemplary Club Head comprising a hosel bore closer to the ground plan than the control club (i.e. low hosel bore) exhibited a similar maximum stress (indicated by a red color) throughout the hosel as the Control Club Head lacking a low hosel bore. Additionally, as shown in FIGS. 5B-5D, the Exemplary Club Head exhibited stresses throughout hosel that lacked any relatively isolated area of high stress when compared to the Control Club Head. The Control Club Head exhibited a concentrated area of stress across the lower end of the hosel, as depicted in FIGS. 6B-6D. This region of concentrated stress indicates the Control Club Head would likely deform along that site if the modeled forces were physically applied to the Control Club Head, such as in post-manufacture bending.

[0218] As stated, the Exemplary Club Head comprising a low hosel bore did not display any highly isolated areas of high stress. Although the maximum stress experienced by both clubs was approximately the same, the Exemplary Club Head exhibited increased stress distribution across the hosel than the Control Club Head. The Exemplary Club Head distributes stress over a larger area, thereby reducing the likelihood of failure or visible stress marks.

[0219] The Exemplary Club Head comprised a lowered hosel bore and shortened hosel compared to the standard club head. All other components of the clubs were the same throughout. The Exemplary Club Head displayed a dispersed stress at the hosel, while the standard club head displayed a line of concentrated stress at a lower portion of the hosel. In conclusion, the shortened hosel and lowered hosel bore reduce the concentration of stress in the lower portion of the hosel and better disperses the stress throughout the entire hosel. This indicates the Exemplary Club Head is able to be bent without a high level of material surface deformation when compared to the Control Club Head lacking a shorted hosel and lowered hosel bore.Example IV—Comparison of Stress Dispersion Between Two Embodiments of the Club Head Described Herein and A Control Club Head

[0220] Example IV provides a qualitative comparison illustrating the effect of a lowered, or deeper, hosel bore on concentration of stress. Specifically, Example IV provides a comparison of stress dispersion based on surface area of two embodiments of the club head described herein, each comprising a lowered hosel bore and lacking an external notch, and one embodiment of a traditional iron-type golf club head comprising typical hosel bore geometry and also a second control lacking an external notch.

[0221] Exemplary Club Head 1 comprises a deeper hosel bore that extends further into the club head than that of the Control Club Head. The hosel bore of Exemplary Club Head 1 terminates along a plane aligned with a heel-most edge of the strike face. Exemplary Club Head 2 comprises a deeper hosel bore that extends further into the club head than that of the Control Club Head and Exemplary Club Head 1. The hosel bore of Exemplary Club Head 2 continues into the club head such that the entire club head is hollowed out and defines a continuous, single void that includes both a body cavity and the hosel bore. The hosel bore walls of the Control Club Head, Exemplary Club Head 1, and Exemplary Club Head 2 comprise a constant thickness that is the same among all three club heads.

[0222] Analysis of each club head's response to constant applied bending forces is shown in FIG. 13 (Control Club Head), FIG. 14 (Exemplary Club Head 1), and FIG. 15 (Exemplary Club Head 2). Illustrated stresses along the hosel indicate the occurrence of bending in response to the forces applied. Referring to FIGS. 13-15, the Control Club Head experienced greater stress per surface area than each of Exemplary Club Head 1 and Exemplary Club Head 2. As such, the Control Club Head experience a higher stress concentration than either Exemplary Club Head. Alternatively, Exemplary Club Head 1 and Exemplary Club Head 2 experience less concentrated and more dispersed stresses than Control Club Head 1 when the same amount of force is applied. As the surface area of the bore increases, bending stresses become less concentrated, dispersing more evenly across the expanded region. In other words, a larger bore surface area provides a greater region over which bending can occur. Consequently, increasing the hosel bore depth enlarges the stress dispersion region, thereby decreasing stress concentration and reducing risk of failure or the occurrence of visible stress marks.Example V—Hosel Wall Thickness Relative to Material Hardness

[0223] Example V provides a comparison between examples of the club head described herein comprising different combinations of material hardness and hosel wall thickness, described in detail below. More specifically, Example V discusses the effect of the interaction between material hardness and wall thickness on the force required to bend the hosel.

[0224] A first exemplary club head (hereafter referred to as “Exemplary Club Head 1-8620”) comprises a hosel wall thickness that is approximately 0.066 inch thick in an upper region, approximately 0.077 inch thick in a middle region, and ranging from 0.075-0.276 inch thick in a lower region. Exemplary Club Head 1-8620 is made of a 8620 steel alloy having a yield strength of 52 ksi and a hardness value of 85 HRB. A second exemplary club head (hereafter referred to as “Exemplary Club Head 2-8620”) comprises a hosel wall thickness that is approximately 0.066 inch thick in an upper region, approximately 0.077 inch thick in a middle region, and ranging from 0.078-0.279 inch thick in a lower region. Exemplary Club Head 2-8620 is made of a 8620 steel alloy having a yield strength of 52 ksi and a hardness value of 85 HRB. A third exemplary club head (hereafter referred to as “Exemplary Club Head 3-8620”) comprises a hosel wall thickness that is approximately 0.066 inch thick in an upper region, approximately 0.077 inch thick in a middle region, and ranging from 0.081-0.282 inch thick in a lower region. Exemplary Club Head 3-8620 is made of a 8620 steel alloy having a yield strength of 52 ksi and a hardness value of 85 HRB.

[0225] A fourth exemplary club head (hereafter referred to as “Exemplary Club Head 1-431”) comprises a hosel wall thickness that is approximately 0.066 inch thick in an upper region, approximately 0.077 inch thick in a middle region, and ranging from 0.075-0.276 inch thick in a lower region. Exemplary Club Head 1-431 is made of a 431 stainless steel material having a yield strength of 80 ksi and a hardness value of 24 HRC. A fifth exemplary club head (hereafter referred to as “Exemplary Club Head 2-431”) comprises a hosel wall thickness that is approximately 0.066 inch thick in an upper region, approximately 0.077 inch thick in a middle region, and ranging from 0.078-0.279 inch thick in a lower region. Exemplary Club Head 2-431 is made of a 431 stainless steel material having a yield strength of 80 ksi and a hardness value of 24 HRC. A sixth exemplary club head (hereafter referred to as “Exemplary Club Head 3-431”) comprises a hosel wall thickness that is approximately 0.066 inch thick in an upper region, approximately 0.077 inch thick in a middle region, and ranging from 0.081-0.282 inch thick in a lower region. Exemplary Club Head 3-431 is made of a 431 stainless steel material having a yield strength of 80 ksi and a hardness value of 24 HRC.

[0226] A seventh exemplary club head (hereafter referred to as “Exemplary Club Head 1-17-4”) comprises a hosel wall thickness that is approximately 0.066 inch thick in an upper region, approximately 0.077 inch thick in a middle region, and ranging from 0.075-0.276 inch thick in a lower region. Exemplary Club Head 1-17-4 is made of a 17-4 stainless steel material having a yield strength of 115 ksi and a hardness value of 32 HRC. An eighth exemplary club head (hereafter referred to as “Exemplary Club Head 2-17-4”) comprises a hosel wall thickness that is approximately 0.066 inch thick in an upper region, approximately 0.077 inch thick in a middle region, and ranging from 0.078-0.279 inch thick in a lower region. Exemplary Club Head 2-17-4 is made of a 17-4 stainless steel material having a yield strength of 115 ksi and a hardness value of 32 HRC. A ninth exemplary club head (hereafter referred to as “Exemplary Club Head 3-17-4”) comprises a hosel wall thickness that is approximately 0.066 inch thick in an upper region, approximately 0.077 inch thick in a middle region, and ranging from 0.081-0.282 inch thick in a lower region. Exemplary Club Head 3-17-4 is made of a 17-4 stainless steel material having a yield strength of 115 ksi and a hardness value of 32 HRC.

[0227] The exemplary club heads described above comprise the same body structure and dimensions, including volume and hosel bore depth and geometry. The exemplary club heads described above club heads vary only in material and lower region hosel wall thickness. The differences in density of the various materials lead to corresponding differences in mass. Differences in hosel wall thickness provide minor additional variations in mass.

[0228] Results illustrated a decrease in magnitude of stress experienced during bending of the hosel resulting from an increase in hardness, and further illustrated a decrease in magnitude of stress experienced during bending of the hosel resulting from an increase in hosel wall thickness. Typically, an increase in material hardness leads to greater stress concentration, but a lower degree of maximum stress experienced and a lower amount of bending when force is kept constant.

[0229] Findings further showed that by altering hosel wall thickness, a similar amount of force input can be provided no matter the material of the hosel. For example, if a material is used for the hosel with a higher hardness and yield strength, the hosel wall thickness needs to be decreased to maintain the level of required force input. Focusing on hosel wall thickness and material properties provides the assembler with a consistent expectation of force, and therefore a consistent feel, when adjusting the loft and lie of a club head post-manufacturing.Example VI—Relationship Between Hosel Length, Head Frequency, and Acoustic Characteristics

[0230] Example VI provides an analytical comparison between club head frequency and its impact on perceived sound characteristics. Particularly, the following analysis utilizes club head modal testing to compare frequencies at mode 7, mode 9, and mode 10. Moreover, the frequencies at these modes were shown to correspond with perceived sound properties.

[0231] While sound perception is inherently subjective and can vary between golfers, trends have determined that certain acoustic characteristics are regarded as favorable. These acoustic characteristics differ between categories of clubs (i.e. player-style irons and game improvement irons); however, categorically similar club heads prove to define similarly favorable sound properties. One method for describing sound properties is through modal analysis. Specifically, modal analysis tests provide quantitative explanations for sound perception in the form of club head frequencies. For this study, club head frequencies at modes 7, 9, and 10 were examined in relation to perceived sound feedback.

[0232] This study established frequency thresholds for both player-style and game improvement irons, providing quantitative criteria to define what constitutes a ‘good-sounding’ club head. Specifically, two club heads from each category with different modal frequency characteristics were analyzed. Based on this analysis, a frequency threshold was determined for each club head, indicating the frequency range to achieve a desirable club head sound.

[0233] For the game improvement iron category, two 7-iron models were compared at three different modes: mode 7, mode 9, and mode 10. Game Improvement Club Head #1 and Game Improvement Club Head #2 comprised ample offset, a rear cavity to optimize perimeter weighting and forgiveness, and a relatively large size to produce confidence. However, Game Improvement Club Head #2 comprised a different badge configuration within the rear cavity than Game Improvement Club Head #1. Moreover, the two game improvement club heads incorporated minor shaping differences in the top rail and hosel. The influence of club head shaping-particularly in the hosel-on club head sound is further detailed in Example VII below.TABLE IIIModal frequencies of two game improvement club heads Game Improvement Club Game Improvement Club Modal Frequency Head #1 Head #2Mode 7 (Hz) 2417 2893 Mode 9 (Hz) 4191 4635 Mode 10 (Hz) 6198 6393

[0234] As illustrated in Table III, Game Improvement Club Head #1 further defined a modal frequency of 2417 at mode 7, 4191 at mode 9, and 6198 at mode 10. Alternatively, Game Improvement Club Head #2 defined a modal frequency of 2893 at mode 7, 4635 at mode 9, and 6393 at mode 10. Table III above illustrates the modal frequencies of each club head.

[0235] During a player test, a group of twenty-five golfers were tasked with hitting a representative number of shots with Game Improvement Club Head #1 and Game Improvement Club Head #2. During testing, the golfers were asked to consider the club head sound, specifically. After the test, it was calculated that 56% of the golfers rated game improvement club head #1 as having a satisfactory sound profile, while 90% of the golfers rated game improvement club head #2 as having a satisfactory sound profile. As such, it was determined that a higher club head frequency tends to lead to a more satisfactory sound. Moreover, due to the significant increase in sound perception between the two game improvement club heads, a frequency threshold delineating a good sounding game improvement 7-iron was postulated to be over 4300 Hz at mode 9 and 6300 Hz at mode 10.

[0236] Additionally, two 7-irons models were compared for the player-preferred iron category. The player-preferred iron club heads comprised minimal offset, limited perimeter weighting, a sleek top-line, and a relatively compact size to optimize shot shaping. However, Player-Preferred Club Head #1 comprised a different rear cavity shape and configuration than Player-Preferred Club Head #2. Moreover, the two player-preferred club heads incorporated minor shaping differences in the top rail and hosel. As previously mentioned, the influence of club head shaping-particularly in the hosel-on club head sound is further detailed in Example VII below.TABLE IVModal frequencies of two player-preferred club heads Player-Preferred Club Player-Preferred Club Modal Frequency Head #1 Head #2Mode 7 (Hz) 3127 3440 Mode 9 (Hz) 5832 6608 Mode 10 (Hz) 7708 8334

[0237] As illustrated in Table IV, Player-Preferred Club Head #1 further defined a modal frequency of 3127 at mode 7, 5832 at mode 9, and 7708 at mode 10. Alternatively, Player-Preferred Club Head #2 defined a modal frequency of 3440 at mode 7, 6608 at mode 9, and 8334 at mode 10. Table IV above illustrates the modal frequencies of each player-preferred club head.

[0238] During a player test, a group of twenty-one golfers were tasked with hitting a representative number of shots with Player-Preferred Club Head #1 and Player-Preferred Club Head #2. During testing, the golfers were asked to regard the club head sound and acoustics, specifically. After testing, the participants compared the two club heads based on perceived sound properties. As such, participants were asked to compare sound desirability between club heads based on a scale of “Undesirable” to “Desirable.” In between these choices, there was: “Moderately Undesirable,”“Slightly Undesirable,”“Slightly Desirable,” and “Moderately Desirable.” Table V below illustrates the player test responses.TABLE VQualitative sound results between two player-preferred club headsSound FeedbackModeratelySlightlySlightlyModeratelyUndesirableUndesirableUndesirableDesirableDesirableDesirableTotal VotesPlayer-004106222PreferredClub Head#1Player-001461122PreferredClub Head#2

[0239] As shown in Table V, Player-Preferred Club Head #2 produced a more favorable sound profile than Player-Preferred Club Head #1. Specifically, 77% of participants rated the acoustics of Player-Preferred Club Head #2 as “Moderately Desirable” or “Desirable,” while only 4.5% of participants rated the acoustics as “Slightly Undesirable.” Alternatively, only 36% of participants rated the acoustics of Player-Preferred Club Head #1 as “Moderately Desirable” or “Desirable,” while 18% of participants rated the acoustics as “Slightly Undesirable.” Accordingly, the sound-frequency relationship previously observed in the game improvement club heads was further demonstrated in this study. Particularly, it was determined that the player-preferred club head with the higher club head frequency tends to lead to a more satisfactory sound. Moreover, due to the significant increase in sound perception between the two player-preferred club heads, a frequency threshold delineating a good sounding players 7-iron was postulated to be over 6000 Hz at mode 9 and 8000 Hz at mode 10.

[0240] As previously mentioned, satisfactory club head acoustic profiles may vary among golfers. However, the test results presented above suggest a relative consensus between club head frequency and appealing sound characteristics. Notably, game improvement club heads achieving a frequency threshold of 4300 Hz at mode 9 and 6300 Hz at mode 10 appeal to a broader spectrum of golfers than similar game improvement club heads with lower frequencies. Likewise, player-preferred club heads demonstrate similar sound proficiency when achieving a frequency threshold of 6000 Hz at mode 9 and 8000 Hz at mode 10 relative to lower frequency player-preferred club heads. Structural variations to the club heads may provide methods to achieving these club head frequencies, such as hosel length manipulation discussed below in Example VII.Example VII—Comparison of Sound Between One Embodiment of the Club Head Described Herein and A Control Club Head

[0241] Example VII provides a qualitative comparison illustrating the effect of a shortened hosel on acoustics (or “sound”). Specifically, described herein is a player test which evaluates qualitative improvements for a golf club head featuring different hosel lengths. In particular, this player test compared two iron-type club heads having similar structures. The player test compared cavity-back style irons having similar badges disposed within the cavities, but featured different hosel lengths. The test further compared the effect of the different structures on player satisfaction regarding the club head sound (or “acoustics”).

[0242] The first iron-type club head (hereafter referred to as the “exemplary club head”) comprised a rear cavity defining a badge. Moreover, the exemplary club head comprised a hosel length of 2.73 inches measured perpendicularly from the hosel top surface to the ground plane.

[0243] The second iron-type club head (hereafter referred to as the “control club head”) differed from the exemplary club head. Specifically, the control club head comprised a rear cavity defining a similar badge to that of the exemplary club head. However, unlike the exemplary club head, the control club head comprised a longer hosel length than that of the exemplary club head. Specifically, the control club head comprised a hosel length of 2.91 inches measured perpendicularly from the hosel top surface to the ground plane.

[0244] The player test was conducted to compare the perceived sound feedback of a 7-iron model of the exemplary club head, featuring the short hosel (i.e. 2.73 inch), with that of a 7-iron model of the control club head (i.e. 2.91 inch). The player test involved thirty low-handicap players who were surveyed about their experience hitting the clubs as they related to sound and acoustics. During the test, each player would hit ten golf shots with each of the control and exemplary clubs. The players tested each club head under similar conditions, with a typical ball-striking surface, and wherein the iron-type club heads included similar shaft lengths and lofts. Thereafter, the players rated their experiences with the exemplary club head and the control club head.

[0245] After testing, the participants compared the two club heads based on perceived sound properties. As such, participants were asked to compare sound desirability between club heads based on a scale of “Much Less Desirable” to “Much More Desirable.” In between these choices, there was: “Moderately Less Desirable,”“Slightly Less Desirable,”“No Difference,”“Slightly More Desirable,” and “Moderately More Desirable.”“Much Less Desirable” represented a substantial decrease in satisfaction relative to the control club head. “Moderately Less Desirable” represented a decrease in satisfaction relative to the control club head. “Slightly Less Desirable” represented a slight decrease in satisfaction relative to the control club head. “No Difference” represented similar satisfaction between the exemplary club head and the control club head. “Slightly More Desirable” represented a moderate increase in satisfaction relative to the control club head. “Moderately More Desirable” represented a substantial increase in satisfaction relative to the control club head. “Much More Desirable” represented a substantial increase in satisfaction relative to the control club head.TABLE VIQualitative sound results between the exemplary and control club headsSound FeedbackMuchModeratelySlightlySlightlyModeratelyMuchLessLessLessNoMoreMoreMoreTotalDesirableDesirableDesirableDifferenceDesirableDesirableDesirableVotesExemplary Club 124693530Head (7i)TABLE VIICompiled sound results between the exemplary and control club heads FEEDBACKNumber of Participants who Voted Slightly More Desirable, 17 Moderately More Desirable, or Much More Desirable Number of Participants who Voted No Difference 6 Total Number Participants 30 Percentage of Participants who Voted Slightly More Desirable, 47% Moderately More Desirable, or Much More Desirable Percentage of Participants who Voted No Difference or Better 77%Tables VI and VII above exhibit participant responses comparing the exemplary club head to the control club head for sound feedback. Tables VII above illustrates the percentage of players who ranked the exemplary club head as “No Difference,”“Slightly More Desirable,”“Moderately More Desirable,” or “Much More Desirable” than the control club head for feedback. The exemplary club head was rated “No Difference,”“Slightly More Desirable,”“Moderately More Desirable,” or “Much More Desirable” when compared to the control club head by 77% of the participants for the 7-iron. Further, the exemplary club head was rated “Slightly More Desirable,”“Moderately More Desirable,” or “Much More Desirable” when compared to the control club head by 47% of the participants for the 7-iron.

[0247] The test resulted in the exemplary club head outperforming the qualitative parameters of the control club head (e.g., perceived sound and acoustics). The participants in the player test felt the exemplary club head had a better sound than the control club head and this sound / acoustic improvement was attributed to the shorter hosel length of the exemplary club head. As confirmed below, the shorter hosel length increases the frequency of the golf club head, thereby leading to a more pleasing sound / acoustic response.

[0248] Example VI described the frequency threshold for game improvement and player-preferred club heads to achieve a pleasing acoustic profile. Particularly, increasing the club head frequency for both categories of club heads resulted in a more satisfying club head sound. As outlined in the aforementioned player test, illustrated in Tables VI and VII, decreasing the hosel length improves the sound profile. This phenomenon can further be described by analyzing the relationship between club head frequency and hosel length.

[0249] These results were confirmed by the player perception test of the current Example (VII). Furthermore, FIG. 46 illustrates the relationship between club head frequency and the decrease in hosel length. Specifically, there is a linear relationship between club head frequency (Hz) and the decrease in hosel length (in.). For this illustration, a game improvement club head and player-preferred club head with initial hosel lengths of 2.82 in. and 2.74 in., respectively, were analyzed. Modal frequency software measured each club head as the respective hosel lengths were shortened. FIG. 46 illustrates that for a game improvement club head and a player-preferred club head, roughly every 0.075″ of hosel shortening provides an extra 100 Hz in club head frequency.

[0250] Club head acoustics play a key role in determining a player's perception of the club head's quality and performance. There are several structural design concepts that can influence club head acoustics. Shortening the hosel length, for instance, has shown to have a significant impact on club head sound perception. This can further be described by the impact that hosel length has on club head frequency. Particularly, a shorter hosel length leads to an increase in club head frequency, helping it reach specific frequency thresholds linked to favorable acoustic performance (see Example VI above).Example VIII—Comparison of Performance Between One Embodiment of the Club Head Described Herein and A Control Club Head

[0251] Described herein is a performance test that compared two iron-type club heads similar in build but for hosel lengths and badge configurations. This Example shows that the weight saved by shortening the hosel can be used in an application of a weighted badge. The performance test compared cavity-back style irons having similar body shapes but comprising different hosel lengths and badge configurations. The different hosel lengths and badge configurations produced differences in mass properties (i.e., CG characteristics) and performance characteristics, described below.

[0252] The first iron-type club head (hereafter referred to as the “control club head”) comprised a rear cavity, a unitary badge disposed within the rear cavity, and a standard hosel length of 2.73 inches. Moreover, the second iron-type club head (hereafter referred to as the “exemplary club head”) comprised a rear cavity, a weighted badge comprising a separate weight member, and a hosel length of 2.43 inches. The weighted badge included roughly 8.4 grams of weight savings from the shorter hosel configuration. Therefore, two factors changed over the control club head: the weighted badge to lower CG and the saved weight by shortening the hosel length. The hosel length defines the distance measured perpendicular from the hosel top surface to the ground plane.TABLE VIIICG comparison between the exemplary and control club heads Club CGy (in.) CGz (in.)Control Club Head 0.515 0.57 Exemplary Club Head 0.495 0.57

[0253] Table VIII above illustrates the CG locations, measured relative to the club head leading edge, of the control and exemplary club heads. A positive CGy measurement indicates a CG location above the leading edge. Similarly, a positive CGz measurement indicates a rearward CG location relative to the leading edge. As shown in Table VIII, the combination of the weighted badge and the shorter hosel length of the exemplary club head improves mass distribution compared to the control club head. Specifically, the exemplary club head comprises a lower center of gravity, described by the CGy distance, without affecting the CGz location. A lower club head CG also corresponds to improved launch and spin characteristics.

[0254] A computer-simulated analysis further compared the weighted badge and shorter hosel performance of the exemplary club head to the unitary badge and longer hosel performance of the control club head. The computer simulation examined the ball speeds of each club head. During simulations, the exemplary club head experienced a 0.2 mph increase in ball speed, on average, compared to the control club head. The ball speed improvement is attributed to the lower club head CG of the exemplary club head, provided by the shorter hosel length and the inclusion of the weighted badge.

[0255] Replacement of one or more claimed elements constitutes reconstruction and not repair. Additionally, benefits, other advantages, and solutions to problems have been described with regard to specific embodiments. The benefits, advantages, solutions to problems, and any element or elements that may cause any benefit, advantage, or solution to occur or become more pronounced, however, are not to be construed as critical, required, or essential features or elements of any or all of the claims, unless such benefits, advantages, solutions, or elements are expressly stated in such claims.

[0256] As the rules to golf may change from time to time (e.g., new regulations may be adopted or old rules may be eliminated or modified by golf standard organizations and / or governing bodies such as the United States Golf Association (USGA), the Royal and Ancient Golf Club of St. Andrews (R&A), etc.), golf equipment related to the apparatus, methods, and articles of manufacture described herein may be conforming or non-conforming to the rules of golf at any particular time. Accordingly, golf equipment related to the apparatus, methods, and articles of manufacture described herein may be advertised, offered for sale, and / or sold as conforming or non-conforming golf equipment. The apparatus, methods, and articles of manufacture described herein are not limited in this regard.

[0257] While the above examples may be described in connection with a iron-type golf club, the apparatus, methods, and articles of manufacture described herein may be applicable to other types of golf club such as a driver wood-type golf club, a fairway wood-type golf club, a hybrid-type golf club, an iron-type golf club, a wedge-type golf club, or a putter-type golf club. Alternatively, the apparatus, methods, and articles of manufacture described herein may be applicable to other types of sports equipment such as a hockey stick, a tennis racket, a fishing pole, a ski pole, etc.

[0258] Moreover, embodiments and limitations disclosed herein are not dedicated to the public under the doctrine of dedication if the embodiments and / or limitations: (1) are not expressly claimed in the claims; and (2) are or are potentially equivalents of express elements and / or limitations in the claims under the doctrine of equivalents.

[0259] Various features and advantages of the disclosure are set forth in the following clauses and claims.

[0260] Clause 1: An iron-type club head, comprising: a club head body, including: a strike face with a strike face front surface intended to impact a golf ball; a strike face rear surface opposite the strike face front surface; a heel end; a toe end, opposite the heel end; a hosel, adjacent the heel end and configured to receive a shaft, the hosel comprising: a hosel bore proximal end defined by a hosel outer transition plane; a hosel bore distal end; a hosel axis extending through a geometric center of a hosel bore tip between the hosel bore proximal end and the hosel bore distal end; a hosel length, measured between the hosel bore distal end and the hosel outer transition plane between 0.75 inch and 2.25 inches; and the hosel does not comprise a tip weight; an interior cavity, in open communication with an exterior of the iron-type club head; and a rear on an opposite side of the interior cavity from the strike face comprising an interior cavity opening perimeter circumscribing the rear and defining an opening into the interior cavity; a mass pad formed as an integral part of the club head body and defining a mass pad depth which varies in a top rail-to-sole direction; a strut extending between two non-adjacent portions of the interior cavity opening perimeter, the strut comprising: a strut angle between 15 degrees and 165 degrees; a strut width between 0.10 inch and 0.60 inch; and an insert undercut further comprising an insert undercut width of less than 0.55 inch; and an insert, comprising: an insert front surface; an insert rear surface opposite the insert front surface and adhesively secured to the strike face rear surface; at least one aperture configured to receive a weight member; and at least one weight member.

[0261] Clause 2: The iron-type club head of clause 1, wherein the hosel length is between 0.75 inch and 1.25 inches.

[0262] Clause 3: The iron-type club head of clause 1, wherein the strut angle is between 45 degrees and 60 degrees.

[0263] Clause 4: The iron-type club head of clause 1, wherein the strut width is between 0.20 inches and 0.30 inches.

[0264] Clause 5: The iron-type club head of clause 4, wherein the insert undercut width is less than 0.30 inches.

[0265] Clause 6: The iron-type club head of clause 1, wherein the insert comprises an insert thickness between 0.50 inch and 1.50 inches measured between the insert front surface and the insert rear surface in a direction perpendicular to a loft plane.

[0266] Clause 7: The iron-type club head of clause 6, wherein the insert thickness is variable.

[0267] Clause 8: The iron-type club head of clause 1, wherein the insert comprises an insert surface area ratio defined as the ratio between a surface area of the insert rear surface and a surface area of the strike face rear surface which is greater than 0.700.

[0268] Clause 9: The iron-type club head of clause 1, wherein an insert perimeter wall and the interior cavity opening perimeter are separated by a gap.

[0269] Clause 10: The iron-type club head of clause 9, wherein the gap defines a gap width between 0.01 inch and 0.05 inch which is variable about the interior cavity opening perimeter.

[0270] Clause 11: An iron-type club head, comprising: a club head body, comprising: a strike face, a top rail, a sole, a toe end, a heel end, and a hosel; a strike face front surface intended for impacting a golf ball and a strike face rear surface opposite the strike face front surface; an interior cavity defined by an area partially enclosed by the top rail, sole, heel end, toe end, and rear surface of the strike face; a hosel bore extending into the hosel and defining a hosel bore length measured from a hosel bore proximal end to the hosel bore distal end; wherein the hosel length is less than the hosel bore length; a hosel length measured from a hosel bore distal end to a transition plane along a hosel axis; and an insert, comprising: an insert rear surface permanently affixed to the strike face rear surface; an insert volume less than a volume of the interior cavity; and a plurality of weight members permanently affixed to the insert, wherein the plurality of weight members are selected from a group of weight members which have a mass of between 5 grams and 15 grams.

[0271] Clause 12: The iron-type club head of clause 11, wherein the hosel bore height is between 120% and 130% of the hosel length.

[0272] Clause 13: The iron-type club head of clause 11, wherein the interior cavity comprises an interior cavity volume and the insert comprises an insert volume which is greater than 40% of the interior cavity volume.

[0273] Clause 14: The iron-type club head of clause 11, wherein the strike face comprises a maximum strike face thickness and a minimum strike face thickness which is less than the maximum strike face thickness.

[0274] Clause 15: The iron-type club head of clause 11, wherein minimum strike face thickness is between 70% and 75% of a maximum strike face thickness.

[0275] Clause 16: An iron-type club head body, comprising: a strike face with a strike face front surface intended to impact a golf ball and a strike face rear surface opposite the strike face front surface; a heel end; a toe end, opposite the heel end; a hosel, adjacent the heel end and configured to receive a shaft; an interior cavity, in open communication with an exterior of the iron-type club head body; a rear on an opposite side of the interior cavity from the strike face, the rear comprising an interior cavity opening perimeter circumscribing the rear and defining an opening into the interior cavity; an insert, adhesively secured to the strike face rear surface and comprising: a first aperture; a first weight member disposed in the first aperture on a front surface of the insert proximate the toe and having a first weight member mass; a second aperture; a second weight member disposed in the second aperture on the front surface of the insert heelward of the first weight member and having a second weight member mass; wherein: the first weight member has a first weight member mass; the second weight member has a second weight member mass; the first weight member mass is less than the second weight member mass; the hosel does not receive a weight member; the hosel comprises a hosel bore, a hosel bore distal end, a hosel bore proximal end, and a hosel axis which passes through a geometric center of the hosel bore proximal end and a geometric center of the hosel bore hosel bore distal end; the hosel has a hosel bore height defined as a distance between the hosel bore distal end and the hosel bore proximal end measured along the hosel axis; the hosel bore height is between 1.0 inch and 2.5 inches; the first weight member has a first weight member center of gravity; the second weight member has a second weight member center of gravity; the iron-type club head body has a club head center of gravity; and a distance between the club head center of gravity and the first weight member center of gravity is greater than a distance between the club head center of gravity and the second weight member center of gravity.

[0276] Clause 17: The iron-type club head body of clause 16, wherein each of a material forming the first weight member and a material forming the second weight member has a density greater than a density of the material of the iron-type club head body.

[0277] Clause 18: The iron-type club head body of clause 16, wherein the insert comprises a tungsten-filled elastomeric material.

[0278] Clause 19: The iron-type club head body of clause 16, wherein the strike face comprises a maximum strike face thickness and a minimum strike face thickness, and the minimum strike face thickness is between 75% and 80% of the maximum strike face thickness.

[0279] Clause 20: The iron-type club head body of clause 16, wherein the strike face defines a strike face height which is between 1.5 inches and 2.2 inches.

[0280] Clause 21: An iron-type club head body comprising: a strike face with a strike face front surface intended to impact a golf ball and a strike face rear surface opposite the strike face front surface; a heel end a toe end, opposite the heel end; a hosel, adjacent the heel end and configured to receive a shaft; a rear comprising an opposite side of the interior cavity from the strike face; the rear comprising a sole bar having a sole bar top surface and a locating feature within the sole bar top surface; a badge secured to the sole bar top surface and to the strike face rear surface through an adhesive member, the badge having a badge top surface with a badge recess configured to receive a badge weight, the badge further comprising a protrusion that is configured to be received by the locating feature; wherein: the badge contacts a portion of the strike face rear surface above the adhesive member; the hosel does not receive a weight member; the hosel comprises a hosel bore, a hosel bore distal end, a hosel bore proximal end, and a hosel axis which passes through a geometric center of the hosel bore proximal end and a geometric center of the hosel bore hosel bore distal end; the hosel has a hosel bore height defined as a distance between the hosel bore distal end and the hosel bore proximal end measured along the hosel axis; the hosel bore height is between 1.0 inch and 2.5 inches.

[0281] Clause 22: An iron-type club head comprising: an iron-type club head body and an insert; wherein: the insert further comprises an insert front surface and an insert rear surface opposite the insert front surface; the iron-type club head body further comprises a strike face, a top rail, a sole, a toe end, a heel end, and a hosel portion; wherein: the strike face further comprises a strike face front surface intended for impacting a golf ball and a strike face rear surface opposite the strike face front surface; and an interior cavity is defined by an area partially enclosed by the top rail, sole, heel end, toe end, and rear surface of the strike face; the insert rear surface is permanently affixed to the rear surface of the strike face; an insert volume is less than a volume of the interior cavity; a plurality of weight members are permanently affixed to the insert; and the plurality of weight members are selected from a group of weight members which have a mass of between 5 grams and 15 grams.

[0282] Replacement of one or more claimed elements constitutes reconstruction and not repair. Additionally, benefits, other advantages, and solutions to problems have been described with regard to specific embodiments. The benefits, advantages, solutions to problems, and any element or elements that may cause any benefit, advantage, or solution to occur or become more pronounced, however, are not to be construed as critical, required, or essential features or elements of any or all of the claims, unless such benefits, advantages, solutions, or elements are stated in such claim.

[0283] Moreover, embodiments and limitations disclosed herein are not dedicated to the public under the doctrine of dedication if the embodiments and / or limitations: (1) are not expressly claimed in the claims; and (2) are or are potentially equivalents of express elements and / or limitations in the claims under the doctrine of equivalents.

Examples

example i

Comparison of Mass Properties Between One Embodiment of Club Head Described Herein And Control Club Head

[0200]Example I provides a comparison between two embodiments of a traditional iron-type golf club head with typical hosel bore geometry and length, one having an external notch and the other with no notch, and a separate embodiment of a club head with the hosel bore geometry described herein with no external notch. More specifically, Example 1 discusses differences in CG and MOI between two traditional club heads and one embodiment of the club head with the low hosel geometry described above, as shown in Table 1.

[0201]As shown in FIG. 6A, the two traditional iron-type golf club head comprising a typical hosel geometry and a hosel notch (hereafter referred to as “Control Club Head 1” and “Control Club Head 2”). Also described herein is an exemplary embodiment having an iron-type golf club head without a notch, a shorter hosel bore geometry and wall tapering as described above. Con...

example ii

Comparison of Material Deformation From Bending Between One Embodiment of Club Head Described Herein and Control Club Head

[0209]Example II provides a comparison illustrating the effect of a lowered, or lengthened, hosel bore on ability to bend and development of highly visible surface deformation resulting from stress. Specifically, Example II compares one embodiment of the club head described herein, comprising an extended hosel bore lacking an external notch, and one embodiment of a traditional iron-type golf club head, comprising typical hosel bore geometry having an external notch.

[0210]The standard club (hereafter referred to as the “Control Club Head”) comprised a body having a heel, toe, upper portion, and a lower portion, a hosel, a hosel bore configured to connect the golf club head with a shaft, and a notch located below the hosel on the heel side of the body. The Exemplary club (hereafter referred to as the “Exemplary Club Head”) comprised a bore extending lower into the ...

example iii

Comparison of FEA Response to Applied Forces at Hosel

[0213]This example provides a qualitative comparison illustrating the effect of a lowered, or lengthened, hosel bore on concentration of stress. Specifically, Example III provides a comparison of stress dispersion based on surface area of one embodiment of the club head described herein, comprising a lowered hosel bore and omitting an external notch, and one embodiment of a traditional iron-type golf club head comprising typical hosel bore geometry and having an external notch.

[0214]Stress values at a site of bending for a standard golf club head were compared to those of an exemplary golf club head. The standard golf club head (hereafter referred to as the “Control Club Head”) comprised a crown, sole, face, rear, hosel, and hosel bore. The exemplary golf club head (hereafter referred to as the “Exemplary Club Head”) comprised similar features with a shortened hosel and lowered hosel bore compared to the standard club. With the ex...

Claims

1. An iron-type club head, comprising:a club head body, including:a strike face with a strike face front surface intended to impact a golf ball;a strike face rear surface opposite the strike face front surface;a heel end;a toe end, opposite the heel end;a hosel, adjacent the heel end and configured to receive a shaft, the hosel comprising:a hosel bore proximal end defined by a hosel outer transition plane;a hosel bore distal end;a hosel axis extending through a geometric center of a hosel bore tip between the hosel bore proximal end and the hosel bore distal end;a hosel length, measured between the hosel bore distal end and the hosel outer transition plane between 0.75 inch and 2.25 inches; and the hosel does not comprise a tip weight;an interior cavity, in open communication with an exterior of the iron-type club head; anda rear on an opposite side of the interior cavity from the strike face comprising an interior cavity opening perimeter circumscribing the rear and defining an opening into the interior cavity;a mass pad formed as an integral part of the club head body and defining a mass pad depth which varies in a top rail-to-sole direction;a strut extending between two non-adjacent portions of the interior cavity opening perimeter, the strut comprising:a strut angle between 15 degrees and 165 degrees;a strut width between 0.10 inch and 0.60 inch; andan insert undercut further comprising an insert undercut width of less than 0.55 inch; andan insert, comprising:an insert front surface;an insert rear surface opposite the insert front surface and adhesively secured to the strike face rear surface;at least one aperture configured to receive a weight member; andat least one weight member.

2. The iron-type club head of claim 1, wherein the hosel length is between 0.75 inch and 1.25 inches.

3. The iron-type club head of claim 1, wherein the strut angle is between 45 degrees and 60 degrees.

4. The iron-type club head of claim 1, wherein the strut width is between 0.20 inches and 0.30 inches.

5. The iron-type club head of claim 4, wherein the insert undercut width is less than 0.30 inches.

6. The iron-type club head of claim 1, wherein the insert comprises an insert thickness between 0.50 inch and 1.50 inches measured between the insert front surface and the insert rear surface in a direction perpendicular to a loft plane.

7. The iron-type club head of claim 6, wherein the insert thickness is variable.

8. The iron-type club head of claim 1, wherein the insert comprises an insert surface area ratio defined as the ratio between a surface area of the insert rear surface and a surface area of the strike face rear surface which is greater than 0.700.

9. The iron-type club head of claim 1, wherein an insert perimeter wall and the interior cavity opening perimeter are separated by a gap.

10. The iron-type club head of claim 9, wherein the gap defines a gap width between 0.01 inch and 0.05 inch which is variable about the interior cavity opening perimeter.

11. An iron-type club head, comprising:a club head body, comprising:a strike face, a top rail, a sole, a toe end, a heel end, and a hosel;a strike face front surface intended for impacting a golf ball and a strike face rear surface opposite the strike face front surface;an interior cavity defined by an area partially enclosed by the top rail, sole, heel end, toe end, and rear surface of the strike face;a hosel bore extending into the hosel and defining a hosel bore length measured from a hosel bore proximal end to the hosel bore distal end;wherein the hosel length is less than the hosel bore length;a hosel length measured from a hosel bore distal end to a transition plane along a hosel axis; andan insert, comprising:an insert rear surface permanently affixed to the strike face rear surface;an insert volume less than a volume of the interior cavity; anda plurality of weight members permanently affixed to the insert, wherein the plurality of weight members are selected from a group of weight members which have a mass of between 5 grams and 15 grams.

12. The iron-type club head of claim 11, wherein the hosel bore comprises a hosel bore height between 120% and 130% of the hosel length.

13. The iron-type club head of claim 11, wherein the interior cavity comprises an interior cavity volume and the insert comprises an insert volume which is greater than 40% of the interior cavity volume.

14. The iron-type club head of claim 11, wherein the strike face comprises a maximum strike face thickness and a minimum strike face thickness which is less than the maximum strike face thickness.

15. The iron-type club head of claim 11, wherein minimum strike face thickness is between 70% and 75% of a maximum strike face thickness.

16. An iron-type club head body, comprising:a strike face with a strike face front surface intended to impact a golf ball and a strike face rear surface opposite the strike face front surface;a heel end;a toe end, opposite the heel end;a hosel, adjacent the heel end and configured to receive a shaft;an interior cavity, in open communication with an exterior of the iron-type club head body;a rear on an opposite side of the interior cavity from the strike face, the rear comprising an interior cavity opening perimeter circumscribing the rear and defining an opening into the interior cavity;an insert, adhesively secured to the strike face rear surface and comprising:a first aperture;a first weight member disposed in the first aperture on a front surface of the insert proximate the toe end and having a first weight member mass;a second aperture;a second weight member disposed in the second aperture on the front surface of the insert heelward of the first weight member and having a second weight member mass;wherein:the first weight member has a first weight member mass;the second weight member has a second weight member mass;the first weight member mass is less than the second weight member mass;the hosel does not receive a weight member;the hosel comprises a hosel bore, a hosel bore distal end, a hosel bore proximal end, and a hosel axis which passes through a geometric center of the hosel bore proximal end and a geometric center of the hosel bore hosel bore distal end;the hosel has a hosel bore height defined as a distance between the hosel bore distal end and the hosel bore proximal end measured along the hosel axis;the hosel bore height is between 1.0 inch and 2.5 inches;the first weight member has a first weight member center of gravity;the second weight member has a second weight member center of gravity;the iron-type club head body has a club head center of gravity; anda distance between the club head center of gravity and the first weight member center of gravity is greater than a distance between the club head center of gravity and the second weight member center of gravity.

17. The iron-type club head body of claim 16, wherein each of a material forming the first weight member and a material forming the second weight member has a density greater than a density of the material of the iron-type club head body.

18. The iron-type club head body of claim 16, wherein the insert comprises a tungsten-filled elastomeric material.

19. The iron-type club head body of claim 16, wherein the strike face comprises a maximum strike face thickness and a minimum strike face thickness, and the minimum strike face thickness is between 75% and 80% of the maximum strike face thickness.

20. The iron-type club head body of claim 16, wherein the strike face defines a strike face height which is between 1.5 inches and 2.2 inches.

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