Golf club heads comprising onset, stability, and toe hang

Abstract

Embodiments of a golf club head comprising an onset shaft that is in front of and on the heel side of the center of gravity (CG) are described herein. The embodiments described herein will provide stability through the putting stroke, get the ball on a true roll, and accommodate different players' stroke types. These embodiments account for player stroke type while providing the true roll (more forward spin) of an onset shaft. Fitting a player to a putter that suits their stroke type allows a player to hit a ball on the player's intended target line thereby increasing the amount putts holed by the player. The goal in the game of golf is to shoot the lowest score and making putts will improve a player's score.

Description

Docket No. KMC-24-059-PCTGOLF CLUB HEADS COMPRISING ONSET, STABILITY, AND TOE HANGCROSS REFERENCE TO RELATED APPLICATIONS

[0001] This claims the benefit of U.S. Provisional Patent Application No. 63 / 718,437, filed on November 8, 2024, U.S. Provisional Patent Application No. 63 / 728,592, filed on December 5, 2024, and U.S. Provisional Patent Application No. 63 / 752,509, filed on January 31, 2025, the contents of the above-described disclosure are incorporated fully herein by reference in its entirety.TECHNICAL FIELD

[0002] This disclosure relates generally to golf club heads and, more particularly, relates to putter-type golf club heads.BACKGROUND

[0003] Some conventional putter-type golf club heads balance mass of the club head by orienting the shaft axis to intersect the center of gravity (CG). Such a balanced head, however provides limited tactile feedback indicating orientation of the club face, which can contribute to offline target putts. Players frequently miss putts beyond four feet. Greater accuracy at these distances will reduce scores. Therefore, a putter head with a shaft axis intersecting the CG eliminates tactile feedback that would spur a player to correct club face angle ( / ., closing or opening the strike face during the putting stroke).

[0004] Other conventional putter-type club heads have slightly off-balanced club head mass by orienting the shaft axis to intersect the club head at a point to the toe side and / or rearward of the CG. Orienting the shaft in this direction relative to CG creates putter torque that is aligned with the torque input by a player, resulting in a greater aggregate torque. These conventional putters will have a face opening torque on the takeaway and a face closing torque on the forward stroke, thereby creating an unbalanced system. This unbalanced system directly corresponds to the player’s input torque; a player will open the face on the takeaway and close the face on the forward stroke, causing misses to the left of target for a right-handed player and right of intended target for a left-handed player. Again, many players struggle to make putts outside of four feet and therefore any edge a player can have to make a putt is crucial to improving their score.Docket No. KMC-24-059-PCTTherefore, a conventional putter head with a shaft axis intersecting toe-ward and rearward of the CG amplifies a player’s input torque by increasing the magnitude to which the face opens and face closes during a putting stroke.BRIEF DESCRIPTION OF THE DRAWINGS

[0005] To facilitate further description of the embodiments, the following drawings are provided in which:

[0006] FIG. 1 illustrates a perspective view of a golf club head comprising an onset shaft axis that is oriented forward and to the heel side of the CG.

[0007] FIG. 2 illustrates a top plan view of the golf club head of FIG. 1.

[0008] FIG. 3 illustrates a rear elevation view of the golf club head of FIG. 1.

[0009] FIG. 4 illustrates a front elevation view of the golf club head of FIG. 1 and further illustrates a coordinate system.

[0010] FIG. 5 illustrates a heel side elevation view of the golf club head of FIG. 1 and further illustrates the coordinate system.

[0011] FIG. 6 illustrates a top plan view of the golf club head of FIG. 1 and further illustrates the coordinate system.

[0012] FIG. 7 illustrates a top plan view of the golf club head of FIG. 1 and further illustrates the location of a shaft intersection point in relation to a face center and CG.

[0013] FIG. 8 illustrates a top plan view of the golf club head of FIG. 1 and further illustrates an intersection zone.

[0014] FIG. 9 illustrates a top plan view of the golf club head of FIG. 1 and further illustrates different intersection zones.

[0015] FIG. 10 illustrates a top plan view of the golf club head of FIG. 1 and further illustrates a straight arc intersection zone.Docket No. KMC-24-059-PCT

[0016] FIG. 11 illustrates a top plan view of the golf club head of FIG. 1 and further illustrates a slight arc intersection zone.

[0017] FIG. 12 illustrates a top plan view of the golf club head of FIG. 1 and further illustrates a strong arc intersection zone.

[0018] FIG. 13 illustrates a top plan view of another embodiment of a golf club head comprising an onset shaft axis that is oriented forward and to the heel side of the CG.

[0019] FIG. 14 illustrates a top plan view of another embodiment of a golf club head comprising an onset shaft that is oriented forward and to the heel side of the CG.

[0020] FIG. 15 illustrates a top plan view of another embodiment of a golf club head comprising an onset shaft that is oriented forward and to the heel side of the CG.

[0021] FIG. 16 illustrates a top plan view of another embodiment of a golf club head comprising an onset shaft that oriented forward and to the heel side of the CG.

[0022] FIG. 17 illustrates a perspective view of another embodiment of a golf club head comprising an onset shaft that is oriented forward and to the heel side of the CG and comprising a face insert.

[0023] FIG. 18 illustrates a top plan view of the golf club head of FIG. 17.

[0024] FIG. 19 illustrates a perspective view of an embodiment of a hosel insert usable with any of the golf club heads disclosed herein.

[0025] FIG. 20 illustrates a perspective view of the hosel insert of FIG. 19 in a golf club head.

[0026] FIG. 21 illustrates a perspective view of another embodiment of a golf club head.

[0027] FIG. 22 illustrates a top plan view of the golf club head of FIG. 21.

[0028] FIG. 23 illustrates a rear elevation view of the golf club head of FIG. 21.

[0029] FIG. 24 illustrates a front perspective view of a blade embodiment of a golf club head comprising an onset shaft that is oriented forward and to the heel side of the CG.Docket No. KMC-24-059-PCT

[0030] FIG. 25 illustrates a rear perspective view of the golf club head of FIG. 24.

[0031] FIG. 26 illustrates a top plan view of the golf club head of FIG. 24.

[0032] FIG. 27 illustrates a front perspective view of a mid-mallet embodiment of a golf club head comprising an onset shaft that is oriented forward and to the heel side of the CG.

[0033] FIG. 28 illustrates a rear perspective view of the golf club head of FIG. 27.

[0034] FIG. 29 illustrates a top plan view of the golf club head of FIG. 27.

[0035] For simplicity and clarity of illustration, the drawings illustrate the general manner of construction, and descriptions and details of well-known features and techniques may be omitted to avoid unnecessarily obscuring embodiments of the disclosure. Additionally, elements in the drawings 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 certain embodiments. The same reference numerals in different figures denote the same elements.DEFINITIONS

[0036] The terms “first,” “second,” “third,” “fourth,” 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.

[0037] The terms “left,” “right,” “front,” “back,” “top,” “bottom,” “over,” “under,” and the like in the description and in the claims, if any, are used for descriptive purposes and not necessarily for describing permanent relative positions. It is to be understood that the terms soDocket No. KMC-24-059-PCT used are interchangeable under appropriate circumstances such that the embodiments of the disclosure described herein are, for example, capable of operation in other orientations than those illustrated or otherwise described herein.

[0038] The terms “couple,” “coupled,” “couples,” “coupling,” and the like should be broadly understood and refer to connecting two or more elements or signals, electrically, mechanically and / or otherwise.

[0039] Described herein are various embodiments of a putter-type golf club head comprising an onset putter shaft that is located on the heel side and forward of the center of gravity. The golf club head described herein can be part of a golf club. A golf club is generally understood to comprise a golf club head, which is configured to receive a shaft. A golf club further comprises a grip, which is secured to the shaft.

[0040] FIGS. 1-29 illustrate various embodiments of a golf club head 100 in various views. For ease of discussion, the features shown on the golf club head 100 are applicable to various embodiments of the club head according to the present disclosure. Any one or more of the features described in the various embodiments below can be used in combination with one another.

[0041] The golf club head 100 comprises a body 101 defining a front 108, a rear 111 opposite the front 108, a heel 104, and a toe 106 opposite the heel 104. The body 101 comprises a strike face 102 near the front 108, a top surface 110 near an upper portion of the golf club head 100, and a sole 112 near a lower portion of the golf club head 100. The body 101 further comprises a hosel 105 for receiving a shaft 113. In some embodiments the hosel 105 can be integral to the body 101. In some embodiments, the hosel 105 comprises a hosel structure to form a hosel bore 107. In other embodiments the hosel 105 comprises a neck that extends from the top surface 110 of the body 101 and locates a hosel upper portion away from the body 101.

[0042] The term “strike face,” 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.” The strike face 102 defines a face center (FC), which is the geometric center point of the strike face perimeter, illustrated in FIG. 3. The face center (FC) can be located in accordance with the definition of a golf governing body such as the United States Golf Association (USGA).Docket No. KMC-24-059-PCT

[0043] As illustrated in FIGS. 4 and 5, the golf club head 100 defines a primary coordinate system with an origin about the face center (FC). The primary coordinate system comprises an X-axis 40, a Y-axis 50, and a Z-axis 60. The X-axis 40 extends in a heel-to-toe direction, parallel to the ground plane 10. The X-axis 40 is positive towards the heel 104 and negative towards the toe 106. The Y-axis 50 extends in a crown-to-sole direction and is orthogonal to both the ground plane 10 and the X-axis 40. The Y-axis 50 is positive towards the top surface 110 and negative towards the sole 112. The Z-axis 60 extends in a front-to-rear direction, parallel to the ground plane 10, and is orthogonal to both the X-axis 40 and the Y-axis 50. The Z-axis 60 is positive in front of the strike face 102 and negative towards the rear 111.

[0044] The primary coordinate system, as described herein, defines an XY plane as a vertical plane extending along the X-axis 40 and the Y-axis 50. The primary coordinate system defines an XZ plane as a horizontal plane extending along the X-axis 40 and the Z-axis 60. The primary coordinate system further defines a YZ plane as a vertical plane extending along the Y-axis 50 and the Z-axis 60. The XY plane, the XZ plane, and the YZ plane are all perpendicular to one another and intersect at the primary coordinate system origin located at the face center (FC). In these or other embodiments, the golf club head 100 can be viewed from a front view when the strike face 102 is viewed from a direction perpendicular to the XY plane. Further, in these or other embodiments, the golf club head 100 can be viewed from a side view when the heel 104 or the toe 106 is viewed from a direction perpendicular to the YZ plane.

[0045] The golf club head 100 comprises a club head center of gravity (hereafter “CG” or “club head CG”), referring to the point at which the mass is centered within the golf club head 100. The club head CG is illustrated in FIGS. 5 and 6.

[0046] The club head CG position can be described with respect to the primary coordinate system, wherein the club head CG position is characterized by locations along the X-axis 40, the Y-axis 50, and the Z-axis 60. The term “CGx” can refer to the club head CG location along the X-axis 40, measured from the face center (FC). The term “CG height” can refer to the club head CG location along the Y-axis 50, measured from the face center (FC). The term “CGY” can be synonymous with the CG height. The term “CG depth” can refer to the club head CG location along the Z-axis 60, measured from the face center (FC). The term “CGz” can be synonymous with the CG depth. Alternatively, the club head CG position can be described with respect to theDocket No. KMC-24-059-PCT leading edge 103, the ground plane 10, or any other reference point, reference plane, or coordinate system.

[0047] The golf club head 100 further comprises a secondary coordinate system with an origin about the club head CG. As illustrated in FIGS. 5 and 6, the secondary coordinate system comprises an X’-axis 70, a Y’-axis 80, and a Z’-axis 90. The X’-axis 70 extends in a heel-to-toe direction. The X’-axis 70 is positive towards the heel 104 and negative towards the toe 106. The Y’-axis 80 extends in a top surface-to-sole direction and is orthogonal to both the Z’-axis 90 and the X’-axis 70. The Y’-axis 80 is positive towards the top surface 110 and negative towards the sole 112. The Z’-axis 90 extends front-to-rear, parallel to the ground plane 10 and is orthogonal to both the X’-axis 70 and the Y’-axis 80. The Z’-axis 90 is positive towards the strike face 102 and negative towards the rear 111.

[0048] The secondary coordinate system, as described herein, defines an X’Y’ 94 plane as a vertical plane extending along the X’-axis 70 and the Y’-axis 80. The secondary coordinate system defines an X’Z’ plane 92 as a horizontal plane extending along the X’-axis 70 and the Z’- axis 90. The primary coordinate system further defines a Y’Z’ 96 plane as a vertical plane extending along the Y’-axis 80 and the Z’-axis 90. The X’Y’ plane, the X’Z’ plane, and the Y’Z’ plane are all perpendicular to one another and intersect at the secondary coordinate system origin located at the club head CG.

[0049] The golf club head 100 comprises one or more moment of inertia values (hereafter “club head MOI”) with respect to the secondary coordinate system. The term “Ixx” can refer to the club head MOI measured about the X’-axis 70. The term “IYY ” can refer to the club head MOI measured about the Y’-axis 80. The term “Izz” can refer to the club head MOI measured about the Z’-axis 90.

[0050] The golf club heads described herein can comprise an Ixx value from 100 g-in2to 650 g-in2, an IYY value from 300 g-in2to 1300 g-in2, and an Izz value from 5 g-in2to 1000 g-in2.

[0051] The golf club heads described herein can comprise a club head mass, defined by the total mass of the club head. The club head mass can be from 300 g to 700 g.Docket No. KMC-24-059-PCT

[0052] The term “putter,” can, in some embodiments, refer to a putter-type club head having a loft angle less than 10 degrees. In many embodiments, the loft angle of the putter can be between 0 and 5 degrees, between 0 and 6 degrees, between 0 and 7 degrees, or between 0 and 8 degrees. For example, the loft angle of the club head can be less than 10 degrees, less than 9 degrees, less than 8 degrees, less than 7 degrees, less than 6 degrees, or less than 5 degrees. For further example, the loft angle of the club head can be 0 degrees, 1 degree, 2 degrees, 3 degrees, 4 degrees, 5 degrees, 6 degrees, 7 degrees, 8 degrees, 9 degrees, or 10 degrees. The putter-type golf club head can be a blade type putter, a mid-mallet type putter, a mallet type putter.

[0053] The term “intended target line” as used herein, refers to a location in front of a player that the player attempts to hit to. A line through this location and the center of the golfball creates a straight line that is the intended target line.

[0054] The term “square to target” as used herein, refers to the face angle being perpendicular to the intended target line. If this occurs the player will start the golf ball on their intended target line which will lead to making more putts.

[0055] The terms “true roll” and “roll true” as used herein, refer to how fast the golfball starts to have top spin after impact. Upon impact the golfball will skid, skip, and / or have back spin due to the physics that occur during the golfball impact. If a putter achieves true roll or causes the ball to roll true (i.e., have top spin) as quick as possible following golfball impact, the ball will have the pace the player intended and therefore go in the hole more often.

[0056] The term “torque” as used herein, refers to the twisting force created by a putter. The torque is calculated by multiplying the golf club head mass by the distance from the CG to the shaft axis.

[0057] The term “shaft axis” as used herein, refers to an axis that aligns with a majority of the shaft. In some shafts, there are bends within the lower 5 inches of the shaft. These bends are omitted when determining the shaft axis.

[0058] The term “onset” as used herein, refers to a shaft axis intersecting at a shaft axis intersection point behind / rearward of the strike face and the face center.Docket No. KMC-24-059-PCT

[0059] The term “club head depth” can refer to the maximum distance the golf club head extends measured along the Z axis.

[0060] The term “attack angle” as used herein, refers to the angle relative to the ground plane the golf club head moves up or down at impact.DESCRIPTION

[0061] Described herein are putter-type club heads that each have a balanced shaft axis intersection point. The shaft axis intersects a point on the club head that is within an intersection zone located to make the putter more stable through the putting stroke, impart a true roll, and adaptable to different stroke types. The shaft axis intersection point is forward of the CG to increase stability by pulling the mass of the club during the putting stroke. The shaft intersection point is rearward of the strike face (z.e., onset) to promptly impart true roll on a ball after impact. The shaft intersection point is also to the heel side of the CG to account for putter stroke arc, which improves the ability to square the face at impact and start the ball on the intended target line. In some embodiments, the shaft intersection point is more heel side of the CG to accommodate golfers with more arced putting strokes. A putter having a shaft axis intersection point meeting these three conditions is more stable, squares the strike face to target more consistently, impacts a golfball to impart a true roll on the golfball after impact, and accommodates different player stroke types.

[0062] A golf club head 100 comprises a shaft axis intersection point 120 located behind the strike face 102 and forward and heel-ward of the CG, as best shown in FIGS. 7 and 8. The shaft axis intersection point 120 is forward of the CG to provide stability to the golf club head 100 since the CG is pulled in the direction of motion. The shaft axis intersection point 120 is located behind the strike face 102 to increase the amount of initial golfball forward roll after impact. Therefore, the ball will roll true sooner to golfball impact, in comparison to a conventional putter comprising a hosel intersection point located in front of a strike face. The shaft axis intersection point 120 located different heel side distances from the CG accounts for different stroke-types. Fitting the putter to a particular stroke type helps the player to square the face by counteracting force input by the player into the putter during a putting stroke. Putters with shaft axis intersection points that meet all three of the above-described location conditions are stableDocket No. KMC-24-059-PCT through the putting stroke, more readily imparts true roll, and accommodate different stroke types.I. Shaft Axis Definitions

[0063] The golf club head 100 can comprise a hosel 105 configured to receive a shaft 113. In some embodiments, the hosel can be located within a body 101. In other embodiments the hosel 105 can comprise a neck that extends from the body 101 to an upper hosel body comprising the hosel bore 107. A shaft axis 114 extends longitudinally through the hosel bore 107. The hosel bore axis can be co-axial with the shaft axis 114. In other embodiments the hosel bore axis is not co-axial with the shaft axis 114. In embodiments in which the hosel bore axis and the shaft axis 114 are not co-axial the shaft can have a bend in it to create an offset from the hosel bore axis and / or an angle with the hosel bore axis. In some embodiments the neck can create an offset from a hosel attachment point and an angle with the YZ plane to define the lie angle of the golf club head 100.II. Shaft Axis Intersection Point Dimensions

[0064] The shaft axis 114 can intersect the X’Z’ 92 plane (z.e?. , the plane parallel to the ground plane and passing through the CG and illustrated in FIG. 6) at a location rearward of the strike face 102 to reduce the time the ball takes to achieve true roll, as best shown in FIG. 7. A putting stroke can be characterized with reference to different planes. For example, a lift arc is made within the YZ plane and correlates to the amount the golf club head lifts from the ground plane during the stroke. The bottom of the lift arc can be defined as the low point of the stroke. The strike face 102 has a positive attack angle at the stroke low point, since the strike face 102 is located forward of the shaft axis intersection point 120. Therefore, the strike face 102 imparts a force that creates more topspin on the golfball and therefore a true roll sooner.

[0065] The shaft axis intersection point 120 can be an onset distance 122 from 0.1 inch to 2.0 inches behind the strike face 102 as projected onto the X’Z’ plane 92. The onset distance can also be characterized by a negative Z value from negative 0.1 inch and negative 2.0 inches. The onset distance 122 is measured from the strike face 102 geometric center to the shaft axis intersection point 120. In some embodiments, the shaft axis intersection point 120 can beDocket No. KMC-24-059-PCT rearward of the strike face geometric center a distance from 0.05 inch to 2.0 inch, 0.1 to 2.0 inches, 0.2 to 2.0 inches, 0.3 to 2.0 inches, 0.4 to 2.0 inches, 0.5 to 2.0 inches, 0.6 to 2.0 inches, 0.7 to 2.0 inches, 0.8 to 2.0 inches, 0.9 to 2.0 inches, 1.0 to 2.0 inches, 1.1 to 2.0 inches, 1.2 to 2.0 inches, 1.3 to 2.0 inches, 1.4 to 2.0 inches, or 1.5 to 2.0 inches. In some embodiments, the shaft axis intersection point 120 can be rearward of the strike face geometric center FC a distance from 0.05 inch to 0.01 inch, 0.1 inch to 0.6 inch, 0.2 inches to 0.7 inches, 0.3 inches to 0.8 inches, 0.4 inches to 0.9 inches, 0.5 inches to 1.0 inch, 0.6 inches to 1.1 inches, 0.7 inches to 1.2 inches, 0.8 inches to 1.3 inches, 0.9 inches to 1.4 inches, 1.0 inch to 1.5 inches, 1.1 inches to 1.6 inches, 1.2 inches to 1.7 inches, 1.3 inches to 1.8 inches, 1.4 inches to 1.9 inches, 1.5 inches to 2.0 inches. In some embodiments, the shaft axis intersection point 120 can be rearward of the strike face geometric center FC at least 0.1 inch, at least 0.2 inches, at least 0.3 inches, at least 0.4 inches, at least 0.5 inches, at least 0.6 inches, at least 0.7 inches, at least 0.8 inches, at least 0.9 inches, at least 1.0 inch, at least 1.1 inches, at least 1.2 inches, at least 1.3 inches, at least 1.4 inches, at least 1.5 inches, at least 1.6 inches, at least 1.7 inches, at least 1.8 inches, at least 1.9 inches, or at least 2.0 inches.

[0066] The shaft axis 114 can intersect the X’Z’ plane 92 forward of the CG allowing the golf club head 100 to pull the CG during a putting stroke. Locating the CG rearward of the shaft axis intersection point 120 creates a stable dynamic system. Therefore, any incorrect force applied by the user always has a counteracting force applied by the putter to square the strike face 102 at impact. Squaring the strike face 102 ensures the ball will start on the intended target line, helping the player make more putts.

[0067] In mallet style putter embodiments, a smaller forward distance can make a high MOI mallet putter feel like a blade putter. This gives a player the MOI forgiveness of the mallet putter but the benefits of a blade putter feel, such as better speed control.

[0068] The shaft axis intersection point 120 can intersect the X’Z’ plane 92 forward of the CG by a forward distance 124 of 0.05 inch to 1.9 inches. The forward distance 124 can also be characterized by a positive Z’ value of 0.05 inch to 1 .9 inches. In some embodiments, the shaft axis intersection point 120 can be forward of the CG a distance between 0.05 inch and 1.9 inches, 0.1 inch to 1.9 inches, 0.2 inch to 1.9 inches, 0.3 inch to 1.9 inches, 0.4 inch to 1.9 inches, 0.5 inch to 1.9 inches, 0.6 inch to 1.9 inches, 0.7 inch to 1.9 inches, 0.8 inch to 1.9Docket No. KMC-24-059-PCT inches, 0.9 inch to 1 .9 inches, 1 .0 inch to 1 .9 inches, 1 .1 inches to 1 .9 inches, 1 .2 inches to 1 .9 inches, 1.3 inches to 1.9 inches, 1.4 inches to 1.9 inches, or 1.5 inches to 1.9 inches. In some embodiments, the shaft axis intersection point 120 can be forward of the CG a distance from 0.05 inch to 0.5 inch, 0.1 inch to 0.6 inch, 0.2 inches to 0.7 inches, 0.3 inches to 0.8 inches, 0.4 inches to 0.9 inches, 0.5 inches to 1.0 inch, 0.6 inches to 1.1 inches, 0.7 inches to 1.2 inches, 0.8 inches to 1.3 inches, 0.9 inches to 1.4 inches, 1.0 inch to 1.5 inches, 1.1 inches to 1.6 inches, 1.2 inches to 1.7 inches, 1.3 inches to 1.8 inches. In some embodiments, the shaft axis intersection point 120 can be forward of the CG a distance of at least 0.1 inch, at least 0.2 inch, at least 0.3 inch, at least 0.4 inch, at least 0.5 inch, at least 0.6 inch, at least 0.7 inch, at least 0.8 inch, at least 0.9 inch, at least 1.0 inch, at least 1.1 inches, at least 1.2 inches, at least 1.3 inches, at least 1.4 inches, at least 1.5 inches, at least 1.6 inches, at least 1.7 inches, or at least 1.8 inches.

[0069] A putting stroke further can be characterized with reference to a stroke arc made within the XZ plane and correlates to the putting stroke type. The shaft axis 114 can intersect the X’Z’ plane 92 at a selected location heel side of the CG to account for different stroke arc types. The closer the shaft axis intersection point 120 is to the heel 104, the more toe hang the golf club head 100 will have. Toe hang is how the golf club head 100 will react during a stroke. As discussed above, the face of a putter opens during the takeaway and closes during the forward stroke due to the natural arc (top view / XZ plane) of the stroke. If a putting stroke has a strong arc (small radius), the strike face will open and close more than a slight arc putting stroke (intermediate radius) and a straight arc putting stroke (large radius). A slight arc putting stroke will open and close the strike face more than a straight arc putting stroke, but less than a strong arc putting stroke. A straight arc putting stroke will open and close the strike face less than both a strong arc putting stroke and a slight arc putting stroke.

[0070] All putting strokes will have at least some arc due to the lie angle of the golf club head 100. Therefore, it is advantageous for the golf club head 100 to counter the force input by the player during the stroke. During the takeaway the player opens the face, and the golf club head 100 counters this by providing a closing force to keep the face square to target. The player closes the face during the forward stroke, and the golf club head 100 provides an opening force to keep the face square to target. Thus, a player with a strong arc will need more toe hang to exert more counter torque. A player with a slight arc would need less toe hang to exert lessDocket No. KMC-24-059-PCT counter torque. A player with a straight arc would need even less toe hang which to exert even less counter torque. Nevertheless, all players will require some amount of counter torque to help them square the face. Intersecting heel side of the CG generates torque that provides the player with tactile feedback to sense where the strike face points to guide the strike face to square.

[0071] Different heel side distances are matched with different player stroke types to improve accuracy. During a putting stroke, all players have various amounts of arc as viewed from above. This entails that the player opens the club face in their takeaway and closes the club face in their forward stroke. A putter head with a shaft axis intersecting the CG or a point toe side and rearward of the CG cannot accommodate a player’s stroke as it cannot counter the opening and closing of the club face. Instead, the conventional putters intersecting toe side and rearward of CG will amplify the input force by the player.

[0072] The shaft axis intersection point 120 can intersect the X’Z’ plane 92 heel side of the CG a heel side distance 126 from 0.01 inch and 3 inches, as best shown in FIG. 7. The heel side distance 126 can also be characterized by a positive X’ value from 0.01 inch and 3.0 inches. In some embodiments, the shaft axis intersection point 120 can intersect the X’Z’ plane 92 heel side of the CG a distance from 0.02 inch to 3 inches, 0.03 inch to 3 inches, 0.04 inch to 3 inches, 0.04 inch to 3 inches, 0.05 inch to 3 inches, 0.06 inch to 3 inches, 0.07 inch to 3 inches, 0.08 inch to 3 inches, 0.09 inch to 3 inches, 0.1 inch to 3 inches, 0.2 inch to 3 inches, 0.3 inch to 3 inches, 0.4 inch to 3 inches, 0.5 inch to 3 inches, 0.6 inch to 3 inches, 0.7 inch to 3 inches, 0.8 inch to 3 inches, 0.9 inch to 3 inches, 1.0 inch to 3 inches, 1.1 inches to 3 inches, 1.2 inches to 3 inches,1.3 inches to 3 inches, 1.4 inches to 3 inches, 1.5 inches to 3 inches, 1.6 inches to 3 inches, 1.7 inches to 3 inches, 1 .8 inches to 3 inches, 1 .9 inches to 3 inches, 2.0 inches to 3 inches, 2.1 inches to 3 inches, 2.2 inches to 3 inches, 2.3 inches to 3 inches, 2.4 inches to 3 inches, 2.5 inches to 3 inches, 2.6 inches to 3 inches, 2.7 inches to 3 inches, 2.8 inches to 3 inches, or 2.9 inches to 3 inches. In some embodiments, the shaft axis intersection point can intersect the X’Z’ plane 92 heel side of the CG a distance from 0.01 inch and 0.09 inch, 0.1 inch to 0.6 inch, 0.2 inches to 0.7 inches, 0.3 inches to 0.8 inches, 0.4 inches to 0.9 inches, 0.5 inches to 1.0 inch, 0.6 inches to 1.1 inches, 0.7 inches to 1.2 inches, 0.8 inches to 1.3 inches, 0.9 inches to 1.4 inches, 1.0 inch to 1.5 inches, 1.1 inches to 1.6 inches, 1.2 inches to 1.7 inches, 1.3 inches to 1.8 inches,1.4 inches to 1.9 inches, 1.5 inches to 2.0 inches, 1.6 inches to 2.1 inches, 1.7 inches to 2.2Docket No. KMC-24-059-PCT inches, 1.8 inches to 2.3 inches, 1 .9 inches to 2.4 inches, 2.0 inches to 2.5 inches, 2.1 inches to 2.6 inches, 2.2 inches to 2.7 inches, 2.3 inches to 2.8 inches, 2.4 inches to 2.9 inches, 2.5 inches to 3.0 inches, 2.6 inches to 3.1 inches, 2.7 inches to 3.2 inches, 2.8 inches to 3.3 inches, or 2.9 inches to 3.4 inches. In some embodiments, the shaft axis intersection point 120 can intersect the X’Z’ plane 92 heel side of the CG a distance inclusively of at least 0.01 inch, at least 0.02 inch, at least 0.03 inch, at least 0.04 inch, at least 0.05 inch, at least 0.06 inch, at least 0.07 inch, at least 0.08 inch, at least 0.09 inch, at least 0.1 inch, at least 0.2 inch, at least 0.3 inch, at least 0.4 inch, at least 0.5 inch, at least 0.6 inch, at least 0.7 inch, at least 0.8 inch, at least 0.9 inch, at least 1.0 inch, at least 1.1 inches, at least 1.2 inches, at least 1.3 inches, at least 1.4 inches, at least 1.5 inches, at least 1.6 inches, at least 1.7 inches, at least 1.8 inches, at least 1.9 inches, at least 2.0 inches, at least 2.1 inches, at least 2.2 inches, at least 2.3 inches, at least 2.4 inches, at least 2.5 inches, at least 2.6 inches, at least 2.7 inches, at least 2.8 inches, or at least 2.9 inches.

[0073] The shaft axis intersection point 120 can be characterized by a positive X’ coordinate and a positive Z’ coordinate, as best shown in FIG. 7. The shaft axis intersection point 120 can have an X’ coordinate from positive 0.001 inch to 3 inches. The X’ coordinate correlates to fitting for the stroke type. The shaft axis intersection point 120 can have a positive Z’ coordinate of 0.05 inch to 3 inches. The Z’ coordinate correlates to the onset distance 122 and the forward distance 124.

[0074] The golf club heads described herein comprise a torque having a magnitude and direction that helps square the strike face to the intended target line. The golf club head torque correlates to the stroke type, a strong arc stroke type needs more torque than a slight arc stroke type, and a slight arc stroke type needs more torque than a straight arc stroke type. The torque of the putters described herein can be from positive 1 N-inch to positive 3 N-inch.

[0075] The putter heads described herein comprise a CG depth 130 from -0.4 inch to -3.0 inches in the Z direction. The CG depth 130 sets up the relationship between the shaft axis intersection point 120 and the CG. As previously discussed, the shaft axis intersection point 120 must remain in front of the CGto provide stability. The CG depth 130 has a greater absolute value than the onset distance absolute value ensuring the CG is pulled and thus provides stability. The shaft axis intersection point 120 must have a forward distance (being in front of the CG) butDocket No. KMC-24-059-PCT still maintain the onset distance. Therefore, the CG depth 130 creates a relationship between the forward distance and the onset distance to retain the onset and pulled CG benefits.III. Intersection Zone

[0076] An intersection zone 150 defines a region in which the shaft axis intersects to provide stability through the putting stroke, impart true roll, and accommodate different stroke types, as best shown in FIG. 8. The intersection zone 150 is co-planar with the X’Z’ plane 92, as best shown in FIG. 8. The intersection zone 150 is bounded by a front edge 152, a rear edge 154, a toe side edge 156, and a heel side edge 158, as best shown in FIG. 8. The front edge 152 can have a Z’ coordinate of 0.5 inch to 2.0 inch. The rear edge 154 can have a Z' coordinate of 0.05 inch to 1.5 inch. The toe side edge 156 can have an X1coordinate of 0.001 inch to 1.75 inch. The heel side edge 158 can have an X' coordinate of 0.5 inch to 2.0 inch. These coordinates set up the intersection zone 150 boundaries.IV. Stroke Type Intersection Zones

[0077] The intersection zone 150 can be divided into three distinct sub intersection sub-zones selected to accommodate different stroke type. The intersection zone 150 can be divided into a straight arc intersection zone 150a, a slight arc intersection zone 150b, and a strong arc intersection zone 150c, best shown in FIG. 9. The straight arc intersection zone 150a is closest to the CG in a heel to toe direction. The strong arc intersection zone 150c is closest to the heel 104. The slight arc intersection zone 150b is in between the straight arc intersection zone 150a and the strong arc intersection zone 150c. The heel side distance 126 relates to strike face 102 opening and closing rotation in a putting stroke. A player having a putting stroke with 0 degrees to 3.33 degrees of strike face rotation requires a shaft axis intersection point 120 that falls within the straight arc intersection zone 150a. A player having a putting stroke with 3.33 degrees to 6.66 degrees of strike face rotation requires a shaft axis intersection point 120 that falls within the slight arc intersection zone 150b. A player having a putting stroke with greater than 6.66 degrees of strike face rotation requires a shaft axis intersection point 120 that falls within the strong arc intersection zone 150c. The correlation between the putting stroke type and the heel side distance 126 provides each putting stroke type a different heel side distance that will square the face at impact by providing applicable counter torques.Docket No. KMC-24-059-PCT

[0078] The straight arc intersection zone 150a accommodates players with a putting stroke that has 0 degrees to 3.33 degrees of strike face rotation, as best shown in FIG. 10. The straight arc intersection zone 150a can be defined by a front edge 152a, a rear edge 154a, a toe side edge 156a, and a heel side edge 158a, as best shown in FIG. 10. The front edge 152a can have a Z’ coordinate of 0.5 inch to 2.0 inch. The rear edge 154a can have a Z' coordinate of 0.1 inch to 1.5 inch. The toe side edge 156a can have an X' coordinate of 0.001 inch. The heel side edge 158a can have an X' coordinate of 0.1 inch. These coordinates define the straight arc intersection zone 150a boundaries. Specifically, the toe side edge 156a and the heel side edge 158a define the heel side distance 126 that accommodates for a straight arc stroke type. The straight arc intersection zone 150a defines any location on a given golf club head that will provide stability through the putting stroke, get the ball on a true roll, and accommodate for a straight arc stroke type.

[0079] The slight arc intersection zone 150b accommodates players with a putting stroke that has 3.33 degrees to 6.66 degrees of strike face rotation, as best shown in FIG. 11. The slight arc intersection zone 150b can be defined by a front edge 152b, a rear edge 154b, a toe side edge 156b, and a heel side edge 158b best shown in FIG. 11. The front edge 152b can have a Z’ coordinate of 0.5 inch to 2.0 inch. The rear edge 154b can have a Z' coordinate of 0.1 inch to 1.5 inch. The toe side edge 156b can have an X1coordinate of 0.1 inch. The heel side edge 158a can have an X' coordinate of 0.35 inch. These coordinates define the slight arc intersection zone 150b boundaries. Specifically, the toe side edge 156b and the heel side edge 158b define the heel side distance 126 that accommodates for a slight arc stroke type. The slight arc intersection zone 150b defines any location on a given golf club head that will provide stability through the putting stroke, get the ball on a true roll, and accommodate for a slight arc stroke type.

[0080] The strong arc intersection zone 150c accommodates players with a putting stroke that has more than 6.66 degrees of strike face rotation, best shown in FIG 12. The strong arc intersection zone 150c can be defined by a front edge 152c, a rear edge 154c, a toe side edge 156c, and a heel side edge 158c best shown in FIG. 12. The front edge 152c can have a Z’ coordinate of 0.5 inch to 2.0 inch. The rear edge 154c can have a Z' coordinate of 0.1 inch to 1.5 inch. The toe side edge 156c can have an X' coordinate of 0.35 inch. The heel side edge 158c can have an X' coordinate of 2.0 inch. These coordinates define the strong arc intersection zone 150c boundaries. Specifically, the toe side edge 156c and the heel side edge 158c define the heel sideDocket No. KMC-24-059-PCT distance 126 that accommodates for a strong arc stroke type. The strong arc intersection zone 150c defines any location on a given golf club head that will provide stability through the putting stroke, get the ball on a true roll, and accommodate for a strong arc stroke type.V. Straight Arc Exemplary Embodiment

[0081] A golf club head 200 configured to benefit a straight arc stroke has a shaft axis intersection point 220 closer to the CG than to the heel of the golf club head. Similar to the embodiment described above, the golf club head 200 comprises a strike face 202, a heel 204, a hosel 205, a toe 206, a front 208, a top surface 210, and a rear 211. The shaft axis intersection point 220, however, can have a heel side distance 226, from the CG, between 0.03 inch and 0.1 inch to benefit a straight arc player, as best shown in FIG. 13. The shaft is oriented to have a shaft axis intersection point 220 that is located within the straight arc intersection zone 150a and can have an onset distance 222 between 0.4 inch and 0.9 inch, to quickly initiate a true roll after impact, and a forward distance 224 between 0.4 inch to 0.8 inch, to provide stability through the putting stroke. The shaft axis intersection point 220 heel side distance 226 creates a dynamic system that imparts the correct amount of counter torque to a straight arc player. The golf club head 200 provides less counter torque than a golf club head comprising a heel side distance 226 greater than 0.1 inch to more equally balance torque input by a player with a straight arc stroke type. The golf club head 200 is stable through the putting stroke, quickly initiates true roll, and accommodates a straight arc stroke type.VI. Slight Arc Exemplary Embodiment

[0082] A golf club head 300 configured to benefit a slight arc stroke type has a shaft axis intersection point 320 located an intermediate distance between the CG and the heel of the golf club head. Similar to the embodiments above, the golf club head 300 comprises a strike face 302, a heel 304, a hosel 305, a toe 306, a front 308, a top surface 310, and a rear 311. The shaft axis intersection point 320, however, can have a heel side distance 326, from the CG, between 0.15 inch to 0.35 inch to benefit a slight arc player, as best shown in FIG. 14. The shaft is oriented to have a shaft axis intersection point 320 that is located within the slight arc intersection zone 150b. The shaft axis intersection point 320 can have an onset distance 322 between 0.4 inch and 0.9 inch, to quickly initiate a true roll after impact, and a forward distance 324 between 0.4 inchDocket No. KMC-24-059-PCT to 0.8 inch, to provide stability through the putting stroke. The shaft axis intersection point 320 heel side distance 326 creates a dynamic system that imparts the correct amount of counter torque to a slight arc player. The counter torque provided by the golf club head 300 is less than that of a golf club head having a heel side distance greater than 0.35 inch and more than that of a golf club head having a heel side distance less than 0.15 inch, to more equally balance torque input by a player with a slight arc stroke type. The golf club head 300 is stable through the putting stroke, quickly initiates true roll, and accommodates a slight arc stroke type.VII. Strong Arc Exemplary Embodiment

[0083] A golf club head 400 configured to benefit a strong arc stroke type has a shaft axis intersection point 420 that is located closer to the heel of the golf club head than to the CG. Similar to the embodiments described above, the golf club head 400 comprises a strike face 402, a heel 404, a hosel 405, a toe 406, a front 408, a top surface 410, and a rear 411. The shaft axis intersection point 420, however, can have a heel side distance 426, from the CG, between 0.35 inch to 1.1 inches to benefit a strong arc player, as best shown in FIG. 15. The shaft is oriented to have a shaft axis intersection point 420 that is located within the strong arc intersection zone 150c. The shaft axis intersection point 420 can have an onset distance 422 between 0.4 inch and 0.9 inch, to quickly initiate a true roll after impact, and a forward distance 424 between 0.4 inch to 0.8 inch, to provide stability through the putting stroke. The shaft axis intersection point 420 heel side distance 426 creates a dynamic system that imparts the correct amount of counter torque to a strong arc stroke type. The counter torque provided by the golf club head 400 is greater than that of a golf club head having a heel side distance 426 less than 0.35 inch. The golf club head 400 is stable through the putting stroke, quickly initiates true roll, and accommodates a strong arc stroke type.VIII. CG depth Embodiment

[0084] A golf club head 500 having a CG depth 130 that is closer to the strike face, is illustrated in FIG. 16. The golf club head 500 has a shaft axis intersection point 520 located closer to the CG, both an onset distance 522 and a forward distance 524 are less than the embodiments described above. Similar to the embodiments described above, the golf club head 500 comprises a strike face 502, a heel 504, a hosel 505, a toe 506, a front 508, a top surface 510,Docket No. KMC-24-059-PCT and a rear 51 1. The shaft axis intersection point 520 can have a heel side distance 526 selected to match the stroke type of the player. For example, the heel side distance 526 is between 0.05 inch and 0.07 inch Alternatively, the golf club head 500 can comprise a heel side distance 526, from the CG, between 0.1 inch and 0.35 inch for slight arc stroke types, or a heel side distance 526 greater than 0.35 inch for strong arc stroke types. In some embodiments, the shaft is oriented to have a shaft axis intersection point 520 that is located within the straight arc intersection zone 150a. In other embodiments, the shaft may be oriented to locate the shaft axis intersection point 520 to intersect the slight arc intersection zone 150b or the strong arc intersection zone 150c. The shaft axis intersection point 520 can have an onset distance 522 between 0.6 inch and 0.8 inch, to initiate the ball on a true roll progression within a short time after impact, and a forward distance 524 between 0.085 inch to 0.145 inch, to provide stability through the putting stroke. The golf club head 500 has a smaller CG depth 130 and maintains all the benefits of the onset distance 522 for true roll, the heel side distance 526 to accommodate stroke type, and the forward distance 524 to pull the CG for stability.IX. Aluminum Insert Embodiment

[0085] A golf club head 600 having a lightweight face that shifts CG rearward, thereby creating space for a larger onset distance is illustrated in FIGS. 17 and 18. As noted above, the CG depth 130 of an onset can be located to account for different stroke types. The structure and / or materials used in different region of the club head, can be selected to shift CG rearward. For example, the strike face typically contributes a substantial portion to the overall club head mass and therefore can significantly influence CG depth 130. Similar to the embodiments above, the golf club head 600 comprises a body 601, a strike face 602, a heel 604, a hosel 605, a toe 606, a front 608, a top surface 610, and a rear 611. The shaft axis intersection point 620 can have a heel side distance 626 selected to match the stroke type of the player. For example, the heel side distance 626, from the CG, is between 0.05 inch and 0.07 inch Alternatively, the golf club head 600 can comprise a heel side distance 626 between 0.1 inch and 0.35 inch for slight arc stroke types, or a heel side distance 626 greater than 0.35 inch for strong arc stroke types. In some embodiments, the shaft is oriented to have a shaft axis intersection point 620 that is located within the straight arc intersection zone 150a. In other embodiments, the shaft may be oriented toDocket No. KMC-24-059-PCT locate the shaft axis intersection point 620 to intersect the slight arc intersection zone 150b or the strong arc intersection zone 150c.

[0086] The golf club head 600, however, has a large strike face formed at least partially of a lightweight or a low-density material to shift the CG towards the rear, which increases space available for an onset distance 622 while maintaining the shaft axis intersection point 620 in front of the CG for stability. The golf club head 600 comprises a strike face 602 comprising a face insert 690 made from a lightweight or a low-density material to shift the CG towards the rear 611. In some embodiments, the face insert 690 material has a density less than 5 g / cm3. A strike face body portion 692 and the face insert 690 form the entirety of the strike face 602. In some embodiments, the face insert 690 material has a density less than the body 601 material. The face insert 690 comprises a face insert perimeter 694 which can share an edge with the leading edge 603. In some embodiments, the face insert perimeter 694 does not share an edge with the leading edge 603. The face insert 690 can form between 15% and 80% of the total surface area of the strike face 602, therefore the strike face body portion 692 can form between 20% and 85% of the total surface area of the strike face 602. The face insert 690 moves the CG towards the rear 611 of the golf club head 600, thereby allowing for more onset distance while still providing a shaft axis intersection point 620 in front of the CG. In some embodiments, the face insert 690 is made from aluminum, titanium, carbon fiber, thermoplastics, thermoplastic polyurethane, polymer, or plastic. The face insert can be used in combination with any of the embodiments described herein. The face insert 690 shifts the CG towards the rear 611 so that the golf club head 600 retains the onset distance 622 for true roll, and the forward distance 624 for stability.X. Hosel Insert

[0087] A hosel insert 760 can be used in combination with any of the embodiments described herein to adjust the loft and lie of the putter, post golf club assembly. The hosel insert 760 is used to connect a shaft to a golf club head 700 while providing a manufacturing advantage of being able to bend the hosel insert 760 to adjust the loft and the lie, as best shown in FIG. 19. Similar to the embodiments above, the golf club head 700 comprises a body 701, a strike face 702, a leading edge 703, a heel 704, a hosel 705, a toe 706, a front 708, a top surface 710, and a rearDocket No. KMC-24-059-PCT711 . The hosel insert 760 can comprise a club head shank 762 that is inserted into a hosel bore and can comprise a shaft shank 764 or a shaft bore opposite the club head shank 762 to receive a shaft. The club head shank 762 and the shaft shank 764 can comprise recessed ribs 766 to help bond the hosel insert 760 to the golf club head 700. The hosel insert 760 comprises a bending region 768 intended to bend to adjust loft and lie and is located between the club head shank 762 and the shaft shank 764 or the shaft bore. The hosel insert 760 is coupled to the club head, as best shown in FIG. 20 and further can couple a shaft to the club head.XI. Hosel Structure

[0088] In some embodiments, a golf club head 800 comprises a hosel 805 that extends upward from a floor 830. Similar to the embodiments above, the golf club head 800 comprises a strike face 802, a heel 804, a hosel 805, a toe 806, a hosel bore 807, a front 808, a top surface 810, a rear 811, a sole 812, and a shaft intersection point 820 located behind the strike face 802 and forward and heel-ward of the CG, as best shown in FIG. 22. The golf club head 800 further comprises a rail 836 forming the front 808. The rail 836 further comprises the strike face 802, a rail top surface 837, a rail top central surface 838 and a rail rear surface 839. In some embodiments, the rail rear surface 839 comprises a flat surface; and in other embodiments, the rail rear surface 839 comprises a curved surface. In some embodiments, the hosel terminates below the vertical height of the rail top central surface 838, as best shown in FIG. 23.

[0089] The golf club head 800 comprises a toe side ballast 832 and a heel side ballast 834 to provide mass towards the club head perimeter and improve MOI. The golf club head 800 comprises a floor 830 located between the toe side ballast 832 and the heel side ballast. 834. In some embodiments, the floor 830 comprises a floor thickness that is less than a toe side ballast thickness and a heel side ballast thickness, wherein the thickness for each of the floor, the toe side ballast, and the heel side ballast is measured along the Y axis. The heel side ballast 834 comprises a heel side ballast top surface 835. The toe side ballast 832 comprises a toe side ballast top surface 833. The floor 830 comprises a floor top surface 831. In some embodiments, the floor top surface 831 is lower than the heel side ballast top surface 835 and the toe side ballast top surface 833.Docket No. KMC-24-059-PCT

[0090] The hosel 805 extends rearward from the rail rear surface 839 and is configured to receive a shaft or a hosel insert. The hosel 805 comprises a hosel toe surface 840, a hosel heel surface 841, a hosel rear surface 842, a hosel interior surface 843, and a hosel top surface 844. The hosel interior surface 843 defines the hosel bore 807. In some embodiments, the hosel top surface 844 is angled relative to the rail top surface 837. In some embodiments, the hosel top surface 844 is below a center region of the rail top surface 837. In some embodiments, the hosel top surface 844 is perpendicular to the hosel interior surface 843. In some embodiments, the hosel top surface 844 is positioned below the rail top surface 837. In some embodiments the hosel 805 is spaced from both the toe side ballast 832 and the heel side ballast 834. In some embodiments the hosel 805 is spaced from both the toe side ballast 832 and the heel side ballast 834 and is closer to the heel side ballast 834 than the toe side ballast 832. In some embodiments, a rearward most point of the hosel 805 taken along the Z axis is at least 0.3 inches from the strike face 802 center measured along the Z axis. In some embodiments, a forward most point of the hosel interior surface 843 taken along the Z axis is at least 0.1 inch rearward of the rail rear surface 839. In some embodiments, the entirety of the shaft is rearward of the rail rear surface 839.XII. Putter Shape and Style

[0091] The putter heads described herein can be any shape or size while still having a shaft axis that intersects at a point on the club head to make the putter more stable through the putting stroke, impart a true roll, and adaptable to different stroke types. A golf club head 900 having a blade style putter shape with an overall club head depth 130 less than or equal to 1.6 inches is illustrated in FIGS. 24-26. Similar to the above embodiments the golf club head 900 comprises a strike face 902, a heel 904, a hosel 905, a toe 906, a hosel bore 907, a front 908, a top surface 910, a rear 911, a sole 912, and a shaft intersection point 920 located behind the strike face 902, and forward and heel-ward of the CG. Similar to the above embodiments, the shaft axis intersection point 920 is located within a shaft axis intersection zone 952. According to other embodiments, a golf club head 1000 comprises a mid-mallet style putter shape and comprises an overall club head depth 130 less than or equal to 2.4 inches and greater than 1.6 inches is illustrated in FIGS. 27-29. Golf club head 1000 comprises a strike face 1002, a heel 1004, a hosel 1005, a toe 1006, a hosel bore 1007, a front 1008, a top surface 1010, a rear 1011, a soleDocket No. KMC-24-059-PCT1012, and a shaft intersection point 1020 located behind the strike face 1002, and forward and heel-ward of the CG. Similar to the above embodiments, the shaft axis intersection point 1020 is located within a shaft axis intersection zone 1052. In still other embodiments, the golf club head is a mallet style putter comprising an overall club head depth greater than 2.4 inches.XIII. Examples

[0092] In a first performance test, a straight arc exemplary club head, a slight arc exemplary club head, and a strong arc exemplary club head were compared for performance as fitted by their stroke types against a control club head that was a zero torque putter head. The control club head comprised a shaft axis that intersected the CG. The straight arc exemplary club head was similar to the golf club head 200 described above and comprised a shaft intersection point with a forward distance of 0.72 inch, an onset distance of 0.6 inch, and a heel side distance of 0.07 inch. The slight arc exemplary club head was similar to the golf club head 300 described above and comprised a shaft intersection point with a forward distance of 0.72 inch, an onset distance of 0.6 inch, and a heel side distance of 0.21 inch. The strong arc exemplary club head was similar to the golf club head 400 described above and comprised a shaft intersection point with a forward distance of 0.72 inch, an onset distance of 0.6 inch, and a heel side distance of 0.36 inch. The control club head comprised a shaft intersection point with a forward distance of 0 inch and a heel side distance of 0 inch.

[0093] In the first performance test, twenty -three players were fit for their stroke type and matched with the correct fitted stroke type exemplary club head. If the player was fit into the straight arc stroke type, they were provided the straight arc exemplary club head. If the player was fit into the slight arc stroke type, they were provided the slight arc exemplary club head. If the player was fit into the strong arc stroke type, they were provided the strong arc exemplary club head. The players were then asked to hit a total of five straight and flat 10-foot putts and a total of five straight and flat 30-foot putts with each club head. Club head data and ball launch data were captured for each putt. The first performance test was conducted with all right-handed players and therefore a right miss was considered a push, and a left miss was considered a pull.

[0094] Fourteen out of the twenty -three players preferred the correct fitted stroke type exemplary club directional control over the control club head directional control. Fifteen out ofDocket No. KMC-24-059-PCT twenty-three players were more confident with the correct fitted stroke type exemplary club head compared to the control club head. A greater closure rate entails the putter is seeking square as the player has opened the strike face during the takeaway and therefore the putter needs to close to return to square. The correct fitted stroke type exemplary club head had an average closure rate across the ten-foot putts of 31.2 degrees per second while the control club head had an average closure rate across the ten-foot putts of 27.4 degrees per second. The correct fitted stroke type exemplary club head had an average closure rate across the thirty-foot putts of 54.8 degrees per second while the control club head had an average closure rate across the thirty -foot putts of 52 degrees per second. The greater closure rate of the correct fitted stroke type exemplary club head demonstrates that the correct fitted stroke type exemplary club head returned to square faster than the control club which helps players hit more puts on the intended line.

[0095] In a second performance test, a straight arc exemplary club head, a slight arc exemplary club head, and a strong arc exemplary club head were compared against a control club head. The control club head comprised a shaft axis intersecting directly in front of the CG, similar to conventional center shafted putters. This tested for a difference between conventional center shafted putters and a correct stroke type fit putter. The control club head comprised a shaft intersection point with a heel side distance of 0 inch. The straight arc exemplary club head was similar to the golf club head 200 described above and comprised a shaft intersection point with a forward distance of 0.72 inch, an onset distance of 0.6 inch, and a heel side distance of 0.07 inch. The slight arc exemplary club head was similar to the golf club head 300 described above and comprised a shaft intersection point with a forward distance of 0.72 inch, an onset distance of 0.6 inch, and a heel side distance of 0.21 inch. The strong arc exemplary club head was similar to the golf club head 400 described above and comprised a shaft intersection point with a forward distance of 0.72 inch, an onset distance of 0.6 inch, and a heel side distance of 0.36 inch.

[0096] In the second performance test, seventeen players were fit for their stroke type and matched with the correct fitted stroke type exemplary club head. If the player was fit into the straight arc stroke type, they were provided the straight arc exemplary club head. If the player was fit into the slight arc stroke type, they were provided the slight arc exemplary club head. If the player was fit into the strong arc stroke type, they were provided the strong arc exemplary club head. The players were then asked to hit a total of ten straight and flat 10-foot putts and aDocket No. KMC-24-059-PCT total of ten straight and flat 30-foot putts with each club head. Club head data and ball launch data were captured for each putt. The second performance test was conducted with all right- handed players and therefore a right miss was considered a push, and a left miss was considered a pull.

[0097] Eleven out of the seventeen players preferred the correct fitted stroke type exemplary club directional control over the control club head directional control. Nine out of seventeen players were more confident with the correct fitted stroke type exemplary club head compared to the control club head. A greater closure rate entails the putter is seeking square as the player has opened the strike face during the takeaway and therefore the putter needs to close to return to square. The correct fitted stroke type exemplary club head had an average closure rate across the ten-foot putts of 28.9 degrees per second while the control club head had an average closure rate across the ten-foot putts of 24.7 degrees per second. The correct fitted stroke type exemplary club head had an average closure rate across the thirty-foot putts of 54.6 degrees per second while the control club head had an average closure rate across the thirty -foot putts of 42.6 degrees per second. The greater closure rate of the correct fitted stroke type exemplary club head demonstrates that the correct fitted stroke type exemplary club head returned to square faster than the control club which helps players hit more puts on the intended line.

[0098] In a third performance test, an exemplary club head was compared to a control club head. The control club head comprised conventional offset meaning the shaft axis was in front of the strike face and the CG. This tested for the benefit of an onset putter over an offset putter. The exemplary club head was similar to the golf club head 300 described above and comprised a shaft intersection point with a forward distance of 0.72 inch, an onset distance of 0.6 inch, and a heel side distance of 0.21 inch.

[0099] In the third performance test, twenty players hit a total of five straight and flat 10-foot putts and a total of five straight and flat 30-foot putts with each club head. Club head data and ball launch data were captured for each putt. The third performance test was conducted with all right-handed players and therefore a right miss was considered a push, and a left miss was considered a pull.Docket No. KMC-24-059-PCT

[0100] The exemplary club head had an average loft at setup of 0.29 degrees; the control club head had an average loft at setup of 0.48 degrees. The exemplary club head had an average loft at impact of 0.90 degrees; the control club head had an average loft at impact of 1.43 degrees. The exemplary club head imparted an average top spin on the ball of 50 revolutions per minute (RPM) for the 10-foot putts and for the 30-foot putts; the control club head imparted an average top spin on the ball of 32 RPM for the 10-foot putts and 30 RPM for the 30-foot putts. The decrease in loft and increase in top spin created by the exemplary club head got the ball on a true roll quicker and thus created a more predictable ball roll than the control club head. The onset distance creates this loft decrease and top spin increase.

[0101] The exemplary club head had an average impact face angle of 0.1 degrees for the 10- foot putts and -0.2 degrees for the 30-foot putts; the control club head had an average impact face angle of -0.2 degrees for the 10-foot putts and -0.6 degrees for the 30-foot putts, wherein a positive degree value indicates right of target and a negative degree value indicates left of target. The exemplary club head had an average horizontal launch of 0.1 degree for the 10-foot putts and -0.2 degrees for the 30-foot putts; the control club head had an average horizontal launch of - 0.3 degrees for the 10-foot putts and -0.7 degrees for the 30-foot putts. The exemplary club head comprising onset starts the golfball closer to the intended target line than the control club head for all putts. Further, the exemplary club head starts the golfball further to the right than the control club head which benefits a player with a left miss.

[0102] In a fourth performance test, a straight arc exemplary club head and a slight arc exemplary club head were compared against a control club head. The control club head comprised a shaft axis that intersected the club head such that it created a lie angle balanced putter and could not fit for a stroke type. The lie angle balanced putter always keeps the strike face square to the path during the stroke, therefore if the player has an incorrect path the put will not start on the intended line. The straight arc exemplary club head was similar to the golf club head 200 described above and comprised a shaft intersection point with a forward distance of 0.72 inch, an onset distance of 0.6 inch, and a heel side distance of 0.07 inch. The slight arc exemplary club head was similar to the golf club head 300 described above and comprised a shaft intersection point with a forward distance of 0.72 inch, an onset distance of 0.6 inch, and a heel side distance of 0.21 inch.Docket No. KMC-24-059-PCT

[0103] In the fourth performance test, twenty -two players were fit for their stroke type and matched with the correct exemplary club head. If the player was fit into the straight arc stroke type, they were provided the straight arc exemplary club head. If the player was fit into the slight arc stroke type, they were provided the slight arc exemplary club head. The players were then asked to complete a putting course consisting of twelve different putts of varying length, horizontal break direction, and vertical break direction. The length of the putts ranged from six feet to forty-five feet. A short putt was defined as a putt between six feet and nine feet in length. A medium putt was defined as a putt between ten feet and twenty feet in length. A long putt was defined as a putt greater than twenty feet in length. The horizontal break was either left to right, right to left, or flat. The vertical break was either uphill, downhill, or flat. The players used either the exemplary club head or the control club head for the first six putts, used the other club for the next twelve putts, and then used the club head they started with for the last six putts. The dispersion of their putts were recorded as players were then asked to provide their preferred club (the correct fitted stroke type exemplary club head versus the control club head). The fourth performance test was conducted with all right-handed players, and therefore a right miss was considered a push, and a left miss was considered a pull.

[0104] Fourteen out of the twenty -two players preferred the correct fitted stroke type exemplary club head that was fit to their stroke type over the control club head. The correct fitted stroke type exemplary club head left less putts short of the hole than the control club head. Across all putts, players left 16% of the putts with the correct fitted stroke type exemplary club head short of the hole and 22% of the putts with the control club head short of the hole. Players left 44% of the long putts with the correct fitted stroke type exemplary club head short of the hole and 52% of the long putts with the control club head short of the hole. Players left 27% of the medium putts with the correct fitted stroke type exemplary club head short of the hole and 45% of the medium putts with the control club head short of the hole. Players left 0% of the short putts with the correct fitted stroke type exemplary club head short of the hole and 3% of the short putts with the control club head short of the hole. It is important not to leave putts short of the hole, since the ball will never have a chance of going in the hole. This is especially important on medium and short putts where the player is trying to make the putt to improve their score. As the data shows, the control club head comprising a lie angle balanced system creates a greater short miss in all putts and more importantly on medium and short putts. Therefore, the correct fittedDocket No. KMC-24-059-PCT stroke type exemplary club head can help a player make more putts as they are able to minimize their short miss.

[0105] As noted in the third performance test, the onset provides a player with a true roll advantage, more top spin after impact, and starting the ball closer to the target line. The fourth performance test shows a speed control advantage, and a preference of the correct fitted stroke type exemplary club head over the control club head. Therefore, the correct fitted stroke type exemplary club heads provide a player with the onset benefit while maintaining a putter that is fit to the player’s stroke type.METHOD

[0106] The golf club head described herein can be made by additive manufacturing, casting, forging, fast forging, milling, metal injection molding, co-molding, injection molding, or any other manufacturing method for metal, plastics, or composites.

[0107] 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.

[0108] 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.CLAUSES

[0109] Clause 1 : A golf club, comprising: a golf club head having a center of gravity; and a shaft having a shaft axis defining a shaft axis intersection point further defined by a forward distance greater than 0.05 inch, an onset distance greater than 0.1 inch, and a heel side distance from 0.01 inch and 3.0 inches.Docket No. KMC-24-059-PCT

[0110] Clause 2: The golf club of clause 1, wherein the heel side distance is from 0.03 inch and 0.1 inch.

[0111] Clause 3: The golf club of clause 1, wherein the heel side distance is from 0.1 inch and 0.35 inch.

[0112] Clause 4: The golf club of clause 1, wherein the heel side distance is from 0.35 inch and 1.1 inch.

[0113] Clause 5: The golf club of clause 1, further comprising a face insert constructed from a material with a density less than 5 g / cm3.

[0114] Clause 6: The golf club of clause 1, further comprising a face insert constructed from a material selected from the group consisting of: aluminum, titanium, carbon fiber, thermoplastics, thermoplastic polyurethane, polymer, or plastic.

[0115] Clause 7: The golf club of clause 1, further comprising a face insert, wherein the face insert forms between 15% and 80% of an overall strike face surface area.

[0116] Clause 8: The golf club of clause 1, further comprising a hosel insert coupling a shaft to the golf club head and further configured to adjust a loft and a lie of the golf club head.

[0117] Clause 9: The golf club of clause 8, wherein the hosel insert includes a club head shank coupled to a hosel bore, and a shaft shank coupled to the shaft.

[0118] Clause 10: The golf club of clause 1, wherein the golf club head further has an Iyy of greater than 300 g inch2.

[0119] Clause 11 : A golf club, comprising: a golf club head defining a center of gravity and an intersection zone defined by a front edge, a rear edge, a toe side edge, and a heel side edge, wherein the front edge has a Z’ coordinate of 1.0 inch, the rear edge has a Z’ coordinate of 0.1 inch, the toe side edge has an X’ coordinate of at least 0.001, and the heel side edge has an X’ coordinate of at most 2.0 inches; and a shaft defining a shaft axis that intersects the intersection zone.Docket No. KMC-24-059-PCT

[0120] Clause 12: The golf club of clause 1 1, wherein the heel side edge has an X’ coordinate of 0.1 inch, thereby defining a straight arc intersection zone, wherein the shaft axis intersects the straight arc intersection zone.

[0121] Clause 13: The golf club of clause 11, wherein the toe side edge has an X’ coordinate of 0.1 inch and the heel side edge has an X’ coordinate of 0.35 inch, thereby defining a slight arc intersection zone, wherein the shaft axis intersects the slight arc intersection zone.

[0122] Clause 14: The golf club of clause 11, wherein the toe side edge has an X’ coordinate of 0.35 inch and the heel side edge has an X’ coordinate of 2.0 inches, thereby defining a strong arc intersection zone, wherein the shaft axis intersects the strong arc intersection zone.

[0123] Clause 15: The golf club of clause 11, further comprising a face insert constructed from a material with a density less than 5 g / cm3.

[0124] Clause 16: The golf club of clause 11, further comprising a face insert constructed from a material selected from the group consisting of: aluminum, titanium, carbon fiber, thermoplastics, thermoplastic polyurethane, polymer, or plastic.

[0125] Clause 17: The golf club of clause 11, further comprising a face insert wherein the face insert forms between 15% and 80% of an overall strike face surface area.

[0126] Clause 18: The golf club of clause 11, further comprising a hosel coupling a shaft to the golf club head and further configured to adjust a loft and a lie of the golf club head.

[0127] Clause 19: The golf club of clause 18, wherein the hosel insert includes a club head shank coupled to a hosel bore, and a shaft shank coupled to the shaft.

[0128] Clause 20: The golf club of clause 11, wherein the golf club head further has an Iyy of greater than 300 g inch2.

[0129] Clause 21 : A golf club head, comprising: a heel, a toe, a front, a rear a toe side ballast, a heel side ballast, and a floor between the toe side ballast and the heel side ballast; a rail forward of the heel side ballast, the toe side ballast, and the floor, and at least partially forming the front, wherein the rail includes a rail top surface and a rail rear surface; and a hosel extending from the floor rearward of the rail rear surface and including a hosel toe surface, a hosel heelDocket No. KMC-24-059-PCT surface, a hosel rear surface, a hosel interior surface defining a hosel bore, and a hosel top surface, the hosel bore configured to receive a shaft or a hosel insert, and the hosel top surface angled relative to the rail top surface.

[0130] Clause 22: The golf club head of clause 21, wherein the hosel top surface is positioned below the rail top surface.

[0131] Clause 23: The golf club head of clause 21, wherein the rail rear surface is flat.

[0132] Clause 24: The golf club head of clause 21, wherein the rail rear surface is curved.

[0133] Clause 25: The golf club head of clause 21, wherein the hosel is spaced from both the heel side ballast and the toe side ballast.

[0134] Clause 26: The golf club head of clause 21, wherein the hosel is closer to the heel side ballast than to the toe side ballast.

[0135] Clause 27: The golf club head of clause 21, wherein the toe side ballast and the heel side ballast have a respective toe side ballast thickness and heel side ballast thickness that are each greater than a floor thickness.

[0136] Clause 28: The golf club head of clause 21, further comprising a heel side ballast top surface, a toe side ballast top surface, and a floor top surface, and wherein the floor top surface is lower than the heel side ballast top surface and the toe side ballast top surface.

[0137] Clause 29: The golf club head of clause 21, wherein a rearward-most point of the hosel taken along a Z axis is at least 0.3 inches from a face center measured along the Z axis.

[0138] Clause 30: The golf club head of clause 21, wherein a forward most point of the hosel interior surface taken along a Z axis is at least 0.1 inch rearward of the rail rear surface.

[0139] Clause 31 : The golf club head of clause 21, wherein an entirety of the shaft is rearward of the rail rear surface.

Claims

Docket No. KMC-24-059-PCTCLAIMS1. A golf club, comprising: a golf club head having a center of gravity; and a shaft having a shaft axis defining a shaft axis intersection point further defined by a forward distance greater than 0.05 inch, an onset distance greater than 0.1 inch, and a heel side distance from 0.01 inch and 3.0 inches.

2. The golf club of claim 1, wherein the heel side distance is from 0.03 inch and 0.1 inch.

3. The golf club of claim 1, wherein the heel side distance is from 0.1 inch and 0.35 inch.

4. The golf club of claim 1, wherein the heel side distance is from 0.35 inch and 1.1 inch.

5. The golf club of claim 1, further comprising a face insert constructed from a material with a density less than 5 g / cm3.

6. The golf club of claim 1, further comprising a face insert constructed from a material selected from the group consisting of: aluminum, titanium, carbon fiber, thermoplastics, thermoplastic polyurethane, polymer, or plastic.

7. The golf club of claim 1, further comprising a face insert, wherein the face insert forms between 15% and 80% of an overall strike face surface area.

8. The golf club of claim 1, further comprising a hosel insert coupling a shaft to the golf club head and further configured to adjust a loft and a lie of the golf club head.

9. The golf club of claim 8, wherein the hosel insert includes a club head shank coupled to a hosel bore, and a shaft shank coupled to the shaft.

10. The golf club of claim 1, wherein the golf club head further has an Iyy of greater than 300 g-inch2.

11. A golf club, comprising: a golf club head defining a center of gravity andDocket No. KMC-24-059-PCT an intersection zone defined by a front edge, a rear edge, a toe side edge, and a heel side edge, wherein the front edge has a Z’ coordinate of 1.0 inch, the rear edge has a Z’ coordinate of 0.1 inch, the toe side edge has an X’ coordinate of at least 0.001, and the heel side edge has an X’ coordinate of at most 2.0 inches; and a shaft defining a shaft axis that intersects the intersection zone.

12. The golf club of claim 11, wherein the heel side edge has an X’ coordinate of 0.1 inch, thereby defining a straight arc intersection zone, wherein the shaft axis intersects the straight arc intersection zone.

13. The golf club of claim 11, wherein the toe side edge has an X’ coordinate of 0.1 inch and the heel side edge has an X’ coordinate of 0.35 inch, thereby defining a slight arc intersection zone, wherein the shaft axis intersects the slight arc intersection zone.

14. The golf club of claim 11, wherein the toe side edge has an X’ coordinate of 0.35 inch and the heel side edge has an X’ coordinate of 2.0 inches, thereby defining a strong arc intersection zone, wherein the shaft axis intersects the strong arc intersection zone.

15. The golf club of claim 11, further comprising a face insert constructed from a material with a density less than 5 g / cm3.

16. The golf club of claim 11, further comprising a face insert constructed from a material selected from the group consisting of aluminum, titanium, carbon fiber, thermoplastics, thermoplastic polyurethane, polymer, or plastic.

17. The golf club of claim 11, further comprising a face insert wherein the face insert forms between 15% and 80% of an overall strike face surface area.

18. The golf club of claim 11, further comprising a hosel coupling a shaft to the golf club head and further configured to adjust a loft and a lie of the golf club head.Docket No. KMC-24-059-PCT19. The golf club of claim 18, wherein the hosel insert includes a club head shank coupled to a hosel bore, and a shaft shank coupled to the shaft.

20. The golf club of claim 11, wherein the golf club head further has an Iyy of greater than 300 g-inch2.

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