Golf club head with lightweight shaft support structure

Abstract

Described herein is a golf club head with a lightweight shaft receiving structure. The lightweight shaft receiving structure comprises one or more lightweight components located in low stress areas of the club head. The lightweight components form portions of the shaft receiving structure that would otherwise be formed by a denser body material. The lightweight shaft receiving structure creates discretionary mass that can be redistributed to improve the mass properties of the club head.

Description

[Technical Field]

[0001] (Cross-reference priority) This application claims the benefits of U.S. Provisional Application No. 63 / 267,183, filed on 26 January 2022, the contents of which are fully incorporated herein by reference.

[0002] This disclosure relates in general to golf clubs, and more particularly to golf club heads having a lightweight and adjustable shaft support structure. [Background technology]

[0003] In the sport of golf, to maximize performance, golf club heads must be customizable to specific players. One example of customizability in golf club head design is providing a club head with loft and / or lie angles tailored to the player. Adjustability of loft and lie angles is often achieved by using an adjustable shaft support mechanism. However, such a mechanism requires an additional component with considerable mass (compared to a non-adjustable shaft support mechanism). By including an adjustable component, it is possible to redistribute it to strategic areas of the club head to optimize the club head's mass characteristics (i.e., center of gravity and moment of inertia), thereby improving club head performance and reducing the amount of discretionary mass.

[0004] The prior art club heads illustrated in Figures 1 and 2 include an adjustable shaft support structure 150. The adjustable shaft support structure 150 includes a shaft sleeve 166 and a hosel 152. The hosel 152 is configured to receive the shaft sleeve 166, which provides considerable mass to the club head 100. A typical prior art shaft support structure 150 includes a hosel 152 and a shaft sleeve 166 that can be inserted into the hosel 152. The shaft sleeve 166 connects a golf club shaft (not shown) to the club head 100 and is configured to provide adjustability of the loft angle and / or lie angle of the club head 100 at address. The hosel 152 may include a hosel bore 156 configured to receive the shaft sleeve 166. The hosel bore 156 defines a hosel bore axis 168 concentric with the hosel bore 156. The hosel 152 may define a hosel bore opening 158 at the upper end of the hosel wall 154. The shaft sleeve 166 and hosel 152 have corresponding receiving shapes, allowing the shaft sleeve 166 to be removably and adjustablely connected within the hosel bore 156. Often, the loft angle and / or lie angle of the club head can be adjusted by adjusting the position of the shaft sleeve 166 within the hosel bore 156. The shaft sleeve 166 can be secured to the hosel 152 by a fastener 176. The fastener 176 extends through a lower opening 174 formed in the shaft receiving structure 150 and can connect to the lower end of the shaft sleeve 166. The fastener 176 allows the shaft sleeve 166 to be removably connected to the hosel 152.

[0005] Many prior art shaft support structures 150 comprise multiple internal components formed by the club head body 101. As shown in Figure 1, many prior art shaft support structures 150 comprise a hosel tube 160 extending from the hosel bore opening 158 to the hosel base 162. The hosel tube 160 holds the shaft sleeve 166 in place and seals the hosel bore 156 from the internal cavity 107. In the prior art, the entire hosel 152, the hosel tube 160, and the hosel base 162 are all typically formed integrally with the club head body 101. This adds considerable mass to the shaft support structure 150. The shaft sleeve 166 can be secured to the hosel 152 by fasteners 176. The fasteners 176 extend through a lower opening 174 formed in the shaft support structure 150 and can connect to the lower end of the shaft sleeve 166.

[0006] As shown in Figures 1 and 2, the hosel tube 160 does not contact and support the shaft sleeve 166 when the shaft sleeve 166 is inserted into the hosel bore 156. Instead, the shaft sleeve 166 is supported primarily by the hosel wall 154 at the hosel bore opening 158 and by tension with the threaded fastener 176. The head of the threaded fastener 176 is in contact with the hosel base 162, close to the lower opening 174. The stress applied to the golf club head 100 through the shaft during use is transmitted through the shaft sleeve 166 at the contact point between the hosel bore opening 158 and the hosel base 162. Since the hosel tube 160 does not contact the shaft sleeve 166, the hosel tube 160 is subjected to only a small portion of the stress load of the golf swing.

[0007] In the prior art shaft support structure 150, the various components described above (i.e., hosel wall 154, hosel tube 160, hosel base 162, shaft sleeve 166, fastener 176, etc.) are formed of steel or other relatively high-density metal materials. Thus, providing an adjustable shaft support structure to a golf club head has conventionally reduced the amount of discretionary mass available to improve the mass characteristics of the club head. There is a need in the art for a shaft support structure that allows for loft and lie adjustment, creates discretionary mass that can be redistributed throughout the club head for performance improvement, and maintains the structural integrity of the club head. [Brief explanation of the drawing]

[0008] To facilitate further explanation of the embodiments, the following drawings are provided.

[0009] [Figure 1] This is a front cross-sectional view showing the shaft support structure of a golf club head in prior art.

[0010] [Figure 2] Figure 1 is a detailed exploded view of the prior art shaft support structure.

[0011] [Figure 3] This is a front perspective view of the wood-type golf club head according to the present invention.

[0012] [Figure 4] Figure 3 is a front view of a wood-type golf club head.

[0013] [Figure 5] Figure 3 is a cross-sectional view of the heel side of a wood-type golf club head.

[0014] [Figure 6] Figure 3 is a diagram of the sole of a wood-type golf club head.

[0015] [Figure 7] This is a front cross-sectional view of a lightweight shaft support structure with a tube insert and a lower end cap.

[0016] [Figure 8] Figure 7 is an exploded cross-sectional view of the lightweight shaft support structure.

[0017] [Figure 9] Figure 7 is a detailed cross-sectional view of the lower end cap.

[0018] [Figure 10] This is a front cross-sectional view showing another embodiment of a lightweight shaft support structure comprising a tube insert and a lightweight collar.

[0019] [Figure 11] Figure 10 is an exploded cross-sectional view of the lightweight shaft support structure.

[0020] [Figure 12] Figure 10 is a detailed exploded view of the lightweight shaft support structure, highlighting the connection between the lightweight collar and the hosel.

[0021] [Figure 13] This is a front cross-sectional view showing another embodiment of a lightweight shaft support structure having a hosel insert.

[0022] [Figure 14] Figure 13 is an exploded cross-sectional view of the lightweight shaft support structure.

[0023] [Figure 15] This is a front cross-sectional view showing another embodiment of a lightweight shaft support structure without a tube insert.

[0024] [Figure 16] This is a heel-side cross-sectional view of another embodiment of a lightweight shaft support structure having an external hosel insert.

[0025] [Figure 17A] This shows the internal stress that occurs during impact in a prior-technology club head equipped with a hosel tube.

[0026] [Figure 17B] This shows the internal stress that occurs during impact in a club head similar to the one in Figure 17A, but without a hosel tube.

[0027] [Figure 18A] This is an internal diagram of the shaft support structure of a wood-type golf club head. [Figure 18B] This is an internal diagram of the shaft support structure of a wood-type golf club head.

[0028] This specification describes various embodiments of golf club heads equipped with lightweight and adjustable shaft support structures. Lightweight shaft support structures have reduced mass, which creates discretionary mass. This discretionary mass can be applied to the club head to improve mass properties such as the center of gravity (CG) position and moment of inertia. The shaft support structure comprises various components, some of which can be made of lightweight materials to reduce the overall mass of the shaft support structure. The reduction in mass of the shaft support structure creates discretionary mass, which can be redistributed strategically to create a high-performance club head with improved mass properties.

[0029] In particular, lightweight shaft support structures provide lightweight (i.e., low-density) components to areas of the club head that do not experience significant stress loads during a golf swing or impact between the club head and the golf ball. In many embodiments, portions of the shaft support structure spaced away from the contact points between the hosel and the shaft sleeve, and / or the contact points between the hosel base and the fasteners, typically experience negligible stress during impact. Therefore, the shaft support structure does not rely on any structural components provided in the aforementioned low-stress areas for the structural integrity of the club head. In many embodiments, lightweight components such as lightweight hosel tube inserts, hosel inserts, or end caps can be provided in the aforementioned areas for purposes other than load-bearing. In some embodiments, certain components typically provided in prior art shaft support structures, such as hosel tubes, can be completely removed without sacrificing the structural integrity of the club head.

[0030] Lightweight shaft bearing structures provide lightweight components to reduce the overall mass of the shaft bearing structure and create discretionary mass. Lightweight shaft bearing structures can create discretionary mass up to 12 grams more compared to similar prior art shaft bearing structures lacking lightweight components. In many embodiments, lightweight shaft bearing structures have a density of 3 g / cm³. 3It has a lightweight hosel tube insert of less than 10

[0031] (definition) To simplify and clarify the illustrations, the drawings show general structural aspects, and well-known features, technical descriptions, and details may be omitted to avoid unnecessarily obscuring the invention. Furthermore, elements in the drawings are not necessarily drawn to scale. For example, the dimensions of some elements in the drawings may be exaggerated relative to others to aid in understanding embodiments of the invention. The same reference figures in different drawings refer to the same element.

[0032] As used herein, the terms “lightweight” or “low density” refer to components of a shaft support structure that are made of a material with a lower density than the metal material that makes up at least a portion of the club head body.

[0033] The terms “replace” or “substitute” in relation to lightweight components of shaft support structures as described herein refer to the ability of the lightweight component in question to form part of a shaft support structure that would otherwise be formed of a higher-density metal club head body material, in embodiments of the prior art. This disclosure uses the prior art as reference to illustrate features of shaft support structures that can be replaced or substituted by the lightweight components described herein.

[0034] The terms “first,” “second,” “third,” “fourth,” etc., used herein and in the claims are used to distinguish similar elements, if any, and are not necessarily used to describe a particular order or chronological order. It should be understood that such terms are interchangeable under appropriate circumstances so that the embodiments described herein may operate in an order other than, for example, those illustrated or otherwise described herein. Furthermore, the terms “include” and “have,” and their variations, are intended to cover non-exclusive inclusion so that a process, method, system, article, device, or apparatus having a list of elements may not necessarily be limited to those elements and may include other elements not explicitly enumerated or specific to such process, method, system, article, device, or apparatus.

[0035] In this specification and in the claims, terms such as “left,” “right,” “front,” “rear,” “up,” “down,” “above,” and “below,” if any, are used for illustrative purposes only and are not necessarily used to describe permanent relative positions. It should be understood that such terms are interchangeable under appropriate circumstances so that embodiments of the invention described herein may operate in orientations other than those illustrated or otherwise described herein.

[0036] Terms such as "connected," "connected," "to connect," and "connecting" should be understood broadly and refer to the connection of two or more elements or signals by electrical, mechanical, and / or other means.

[0037] The term "striking face" refers to the front of the club head configured to strike the golf ball. The term "striking face" can be used interchangeably with "face."

[0038] In this specification, the term “periphery of the striking face” may refer to the edge of the striking face. The periphery of the striking face may be located along the outer edge of the striking face where the curvature deviates from the bulge and / or roll of the striking face.

[0039] In this specification, the terms “geometric center point” or “geometric center” of the striking face may refer to the geometric center point of the outer periphery of the striking face, and the midpoint of the face height of the striking face. In the same or other examples, the geometric center point may also be the center of the engineering impact zone, which can be defined by the area of ​​grooves on the striking face. Alternatively, the geometric center point of the striking face may be determined according to the definition of a golf governing body such as the United States Golf Association (USGA).

[0040] In this specification, the term "contact surface" may refer to a reference plane relating to the surface on which the golf ball is placed. The contact surface may be the horizontal plane that is in contact with the sole of the club at the address position.

[0041] In this specification, the term "loft plane" may refer to a reference plane tangent to the geometric center point of the striking face.

[0042] In this specification, the term “loft angle” may refer to the angle measured between the loft plane and a plane perpendicular to the ground plane.

[0043] In this specification, the term "face height" may refer to the distance measured parallel to the loft plane between the upper edge of the outer perimeter of the striking face and the lower edge of the outer perimeter of the striking face.

[0044] As used herein, the term “lie angle” may refer to the angle between the hosel axis, which extends through the hosel, and the contact surface. The lie angle is measured when viewed from the front.

[0045] In this specification, the "depth" of a golf club head can be defined as the dimension from the front to the back of the golf club head.

[0046] As described herein, the “height” of a golf club head can be defined as the dimension from the crown to the sole of the golf club head. In many embodiments, the height of the club head may be measured according to the regulations of a golf governing body such as the United States Golf Association (USGA).

[0047] As described herein, the “length” of a golf club head can be defined as the dimension from heel to toe of the golf club head. In many embodiments, the length of the club head may be measured according to the regulations of a golf governing body such as the United States Golf Association (USGA).

[0048] As described herein, the "geometric center height" of a fairway-type golf club head refers to the height measured perpendicularly from the ground surface to the geometric center point of the golf club head.

[0049] In this specification, the "leading edge" of a club head can be identified as the sole-side portion of the outer perimeter of the striking face.

[0050] The "XYZ" coordinate system for golf club heads described herein is based on the geometric center of the striking face. Dimensions of golf club heads as described herein may be measured based on the coordinate system defined below. The coordinate system is illustrated with reference to Figures 4 and 5. The geometric center 120 of the striking face 102 defines a coordinate system having an origin located at the geometric center 120 of the striking face 102. The coordinate system defines the X-axis 1040, the Y-axis 1050, and the Z-axis 1060. The X-axis 1040 passes through the geometric center 120 of the striking face 102 and extends in the direction from the heel 104 to the toe 106 of the club head 100. The Y-axis 1050 extends through the geometric center 120 of the striking face 102 in the direction from the crown 110 to the sole 112 of the golf club head 100. The Y-axis 1050 is perpendicular to the X-axis 1040. The Z-axis 1060 extends from the front end 108 to the rear end 111 of the golf club head 100, passing through the geometric center 120 of the striking face 102. The Z-axis 1060 is perpendicular to both the X-axis 1040 and the Y-axis 1050.

[0051] The term "center of gravity" or "CG position" can refer to the position of the club head's center of gravity (CG) 199 relative to the XYZ coordinate system, and the CG position is characterized by its position along the X-axis 1040, Y-axis 1050, and Z-axis 1060. The term "CGx" can refer to the CG position along the X-axis 1040, measured from the origin 120. The term "CG height" can refer to the CG position along the Y-axis 1050, measured from the origin 120. The term "CGy" can be synonymous with CG height. The term "CG depth" can refer to the CG position along the Z-axis 1060, measured from the origin 120. The term "CGz" can be synonymous with CG depth.

[0052] The XYZ coordinate system of the golf club head described herein defines an XY plane extending through the X-axis 1040 and the Y-axis 1050. The coordinate system defines an XZ plane extending through the X-axis 1040 and the Z-axis 1060. The coordinate system further defines a YZ plane extending through the Y-axis 1050 and the Z-axis 1060. The XY plane, the XZ plane, and the YZ plane are all perpendicular to each other and intersect at the coordinate system origin located at the geometric center 120 of the striking face 102. In these embodiments, or other embodiments, the golf club head 100 can be viewed from a front view when the striking face 102 is viewed from a direction perpendicular to the XY plane. Furthermore, in these embodiments, or other embodiments, the golf club head 100 can be viewed from a side view or a side section view when the heel 104 is viewed from a direction perpendicular to the YZ plane.

[0053] As shown in Figures 4 and 5, the golf club head 100 further comprises a coordinate system centered on the center of gravity 199. The coordinate system comprises an X' axis 1070, a Y' axis 1080, and a Z' axis 1090. The X' axis 1070 extends from the heel to the toe. The X' axis 1070 is positive toward the heel 104 and negative toward the toe 106. The Y' axis 1080 extends from the sole to the crown and is perpendicular to both the Z' axis 1090 and the X' axis 1070. The Y' axis 1080 is positive toward the crown 110 and negative toward the sole 112. The Z' axis 1090 extends in the front-to-back direction, is parallel to the ground surface, and is perpendicular to both the X' axis 1070 and the Y' axis 1080. The Z' axis 1090 is positive toward the striking face 102 and negative toward the rear 111.

[0054] The term "moment of inertia" (hereinafter, "MOI") as defined in this specification, or the phrase, can refer to the value measured about CG199. The term "Ixx" can refer to the MOI measured in the direction from the heel to the toe about the X'-axis 1070. The term "Iyy" can refer to the MOI measured in the direction from the sole to the crown about the Y'-axis 1080. The term "Izz" can refer to the MOI measured in the front-back direction about the Z'-axis 1090. The MOI values Ixx, Iyy, and Izz determine how forgiving the clubhead 100 is with respect to an impact off-center from the center of the golf ball.

[0055] The "driver-type golf clubhead", described in this specification and also referred to as a driver, can be defined by a specific dimensional range. In particular, a driver as described with respect to the present invention disclosed herein includes a loft angle and a volume within the ranges defined below. The ranges defined below limit the driver-type golf clubhead to a driver-type clubhead. In other words, the driver-type golf clubhead cannot be a fairway-type, hybrid-type, iron-type, or putter-type golf clubhead.

[0056] The "loft angle" of the driver as defined in this specification can be less than about 16 degrees, less than about 15 degrees, less than about 14 degrees, less than about 13 degrees, less than about 12 degrees, less than about 11 degrees, or less than about 10 degrees.

[0057] The "volume" of the driver as defined in this specification is greater than about 300 cm 3 greater than, greater than about 350 cm 3 greater than, greater than about 400 cm 3 greater than, greater than about 425 cm 3 greater than, greater than about 450 cm 3 greater than, greater than about 475 cm 3 greater than, greater than about 500 cm greater than 3 , greater than about 525 cm 3 greater than, greater than about 550 cm 3 greater than, greater than about 575 cm 3Larger, approximately 600cm 3 Larger, approximately 625cm 3 Larger, approximately 650cm 3 Larger, approximately 675cm 3 Larger, or approximately 700cm 3 It can become larger.

[0058] As defined herein, a “fairway type golf club head” is a club head having a specific loft, volume, and dimensions that can be defined by a specific range of dimensions. In particular, the fairway type club heads described in relation to the present invention disclosed herein include loft angles and volumes within the ranges defined below. The ranges defined below limit the fairway type golf club head to a fairway type club head. In other words, a fairway type golf club head cannot be a driver type, hybrid type, iron type, or putter type golf club head.

[0059] The "loft angle" of a fairway-type club head as defined herein can be less than approximately 35 degrees, less than approximately 34 degrees, less than approximately 33 degrees, less than approximately 32 degrees, less than approximately 31 degrees, or less than approximately 30 degrees. In some embodiments, the loft angle of a fairway-type golf club head can be greater than approximately 12 degrees, greater than approximately 13 degrees, greater than approximately 14 degrees, greater than approximately 15 degrees, greater than approximately 16 degrees, greater than approximately 17 degrees, greater than approximately 18 degrees, greater than approximately 19 degrees, or greater than approximately 20 degrees. For example, in some embodiments, the loft angle of a fairway-type golf club head can be between 14 and 35 degrees, between 15 and 35 degrees, between 20 and 35 degrees, or between 12 and 30 degrees.

[0060] In this book, the "volume" of a fairway-type club is approximately 170 cm³. 3 Less than approximately 180cm 3 Less than approximately 190cm 3 Less than or approximately 200 cm 3 It can be less than 160 cm³. However, the volume of a fairway-type club is 160 cm³. 3It cannot be less than this. In some embodiments, the volume of a fairway-type club head is approximately 150 cm³. 3 From 200cm 3 Between these points, approximately 160cm 3 From 170cm 3 Between these two points, approximately 160cm 3 From 180cm 3 Between, or approximately 170cm 3 From 190cm 3 It can be between these two. The volume of a fairway-type club is 200 cm³. 3 It cannot exceed this. In one exemplary embodiment, the volume of a fairway-type club is 169 cm³. 3 That is the case.

[0061] As defined herein, a “hybrid golf club head” is a club head having a specific loft, volume, and dimensions that can be defined by a specific range of dimensions. In particular, the fairway club head described in relation to the invention disclosed herein has a loft angle and volume within the range defined below. The range defined below limits the hybrid golf club head to a hybrid club head. In other words, a hybrid golf club head cannot be a driver type, fairway type, iron type, or putter type golf club head.

[0062] The "loft angle" of a hybrid club head as defined herein can be less than about 40 degrees, less than about 39 degrees, less than about 38 degrees, less than about 37 degrees, less than about 36 degrees, less than about 35 degrees, less than about 34 degrees, less than about 33 degrees, less than about 32 degrees, less than about 31 degrees, or less than about 30 degrees. Furthermore, in many embodiments, the loft angle of a hybrid club head can be greater than about 16 degrees, greater than about 17 degrees, greater than about 18 degrees, greater than about 19 degrees, greater than about 20 degrees, greater than about 21 degrees, greater than about 22 degrees, greater than about 23 degrees, greater than about 24 degrees, or greater than about 25 degrees.

[0063] The “volume” of a hybrid club head as defined herein can be less than about 200cc, less than about 175cc, less than about 150cc, less than about 125cc, less than about 100cc, or less than about 75cc. In some embodiments, the volume of a hybrid club head can be about 100cc to 150cc, about 75cc to 150cc, about 100cc to 125cc, or about 75cc to 125cc.

[0064] (explanation) I. General structure of a golf club head This specification describes various embodiments of a lightweight shaft support structure that can be applied to a wood-type golf club head to create discretionary mass and improve the mass characteristics of the club head. The lightweight shaft support structure can be applied to a wood-type golf club head. Referring to the drawings, club head 100 is used to illustrate the general characteristics of any club head, to which any of the lightweight shaft support structures described below can be applied. Figures 3 to 6 schematically illustrate the wood-type golf club head 100 in various diagrams. Specifically, Figure 3 shows a front perspective view of the wood-type club head 100. The club head 100 may comprise a striking face 102 and a body 101 that are fixed together and define a substantially closed / hollow internal cavity 107 (illustrated in Figure 5). The club head 100 comprises a crown 110, a sole 112 opposite the crown 110, a heel 104, a toe 106 opposite the heel 104, a front section 108, and a rear section 111 opposite the front section 108. The body 101 may further include a skirt 114 positioned adjacent to the crown 110 and the sole 112. The skirt 114 extends from near the heel 104 to near the toe 106 of the club head 100.

[0065] As described in this disclosure, the club head 100 is a wood-type club head, such as a driver, fairway wood, or hybrid. Although various diagrams of fairway wood-type club heads are shown, it should be noted that any of the lightweight shaft support structures described herein can be applied to any wood-type club head, including driver-type or hybrid-type club heads. The striking face 102 and body 101 can define an internal cavity 107 of the club head 100. The body 101 can extend over the crown 110, sole 112, heel 104, toe 106, rear 111, and the outer periphery of the front 108. In these embodiments, the body 101 defines an opening in the front 108 of the club head 100, and the striking face 102 is positioned within the opening to form the club head 100. In other embodiments, the striking face 102 extends over the outer periphery of the front 108 and may include a return portion 122 extending rearward from the striking face 102. The return portion 122 may extend over at least one of the crown 110, sole 112, heel 104, and toe 106. In embodiments having the return portion 122, the return portion 122 of the striking face 102 is fixed to the body 101 to form the club head 100. In these embodiments, as shown in Figure 3, the club head 100 may resemble a cup face or face wrap design.

[0066] As described above and shown in Figures 1 and 2, the club head 100 includes a shaft support structure 150. The shaft support structure 150 includes a hosel 152. The hosel 152 can receive a shaft sleeve 166 and a golf shaft (not shown). The shaft sleeve 166 can be connected to the end of a golf shaft (not shown). The shaft sleeve 166 can be connected to the hosel 152 in multiple configurations, thereby allowing the golf shaft to be fixed to the hosel 152 at multiple angles.

[0067] Referring to Figures 5 and 6, the club head 100 may include a weight port 125 configured to receive a removable weight 126. In many embodiments, the weight port 125 may be located in the sole 112 and / or in the skirt 114, adjacent to the rear 111. The club head 100 may further include a mass pad 163 or weight pad (hereinafter, "mass pad"). In many embodiments, the mass pad 163 may be located on the sole 112 and in the internal cavity 107. In other embodiments, the mass pad 163 may be located on the sole 112 and the skirt 114, as well as in the internal cavity 107. In yet another embodiment, the club head 100 may include one or more weight ports 125 and one or more mass pads 163. The removable weight 126 and mass pad 163 can adjust the moment of inertia (MOI) characteristics and the center of gravity (CG) position. In many embodiments, the discretionary mass generated by the lightweight shaft support structure described herein can be redistributed by adding mass to a removable weight 126 or mass pad 163 to improve the mass characteristics of the club head.

[0068] In many embodiments, a substantial portion of the club head body 101 can be formed from a metallic material. The lightweight shaft support structures described herein can be applied to club heads 100 having a body 101 that is entirely made of metal or made of multiple materials. In certain embodiments, the lightweight shaft support structures described herein can be applied to club heads 100 in which at least a portion of the body 101 is formed from a lightweight non-metallic material. However, in the following descriptions of various shaft support structures, the term “body material” is used in reference to the metallic material forming part of the body.

[0069] The body material may include, but is not limited to, steel, steel alloys, stainless steel alloys, nickel, nickel alloys, cobalt, cobalt alloys, titanium alloys, amorphous metal alloys, or other similar materials. For example, the body material may include, but is not limited to, Ti-8Al-1Mo-1V alloy, 17-4 stainless steel, C300, C350, Ni(nickel)-Co(cobalt)-Cr(chromium)-steel alloy, 565 steel, AISI type 304, or AISI type 630 stainless steel, 17-4 stainless steel, titanium alloy, for example, Ti-6-4, Ti-3-8-6-4-4, Ti-10-2-3, Ti15-3-3, Ti15-5-3, Ti185, Ti6-6-2, Ti-7s, Ti-9s, Ti-92, T9s+, or Ti-8-1-1 titanium alloy, amorphous metal alloy, or other similar metals. The body material has a higher density than the lightweight material used to provide lightweight components for the shaft bearing structure. Generally, the density of the body material is about 4 g / cm³. 3 From approximately 10g / cm³ 3 It can be set between these two. In many embodiments of the lightweight shaft support structure described below, the shaft support structure can be formed by a combination of body material and lightweight material.

[0070] (II. Lightweight shaft support structure) In many prior art club heads, the adjustable shaft support structure comprises various components integrally formed from the body material. The material of the shaft support structure is typically the same as at least a large portion of the club head body, and is typically a casting-suitable material such as steel or titanium alloy. In many prior art multi-material club heads, the shaft support structure is integrally formed with the metal parts of the body and has the same metal material as the body. Metallic body material is necessary for durability and mass distribution in many parts of the body (sole, crown return, rear, etc.). However, certain parts of the shaft support structure (i.e., the hosel tube) do not bear a significant portion of the impact load and therefore do not need to be formed entirely from the body material. As will be discussed in more detail below, the shaft support structure does not have the same strength requirements as the sole, crown return, or other parts of the club head formed by the body. As an example, the stress applied to the golf club head through the shaft during use is transmitted through the shaft sleeve at the contact point between the hosel bore opening and the hosel base. Since the hosel tube does not contact the shaft sleeve, it bears only a small portion of the stress load of the golf swing. Therefore, shaft support structures such as hosel tubes can be made from lightweight materials without compromising the structural integrity of the golf club head.

[0071] When a club head is used to strike a golf ball, the parts of the golf club head within and around the shaft support structure experience less stress. Therefore, these parts do not require the same material properties as the parts of the golf club head that experience greater stress during impact with the golf ball. As a result, materials with lower strength and lower density (lighter weight) can be used to replace the parts of the shaft support structure that experience less stress.

[0072] Lightweight and adjustable shaft bearing structures typically generate discretionary mass by replacing (or, in some cases, completely removing) the portion of the shaft bearing structure that is formed from the body material with lightweight components. In many embodiments, the hosel body, hosel transition, hosel tube, and / or a portion of the hosel base can be constructed from lightweight material. Such components can be made from lightweight material (i.e., material lighter than the body material) to reduce the mass of the shaft bearing structure.

[0073] A lightweight shaft support structure may have one or more parts or components made of a lightweight material having a density lower than that of the body material. In many embodiments, one or more parts or components of the lightweight shaft support structure may be made of a polymer material, composite material, or lightweight metal material having a density lower than that of the metal forming the body. In many embodiments, one or more parts or components of the lightweight shaft support structure may be made of a polymer resin or a material including a fiber-reinforced polymer resin, but are not limited to these. The polymer resin may include a thermosetting resin, or a thermoplastic resin, a filled thermoplastic material, a fiber-reinforced composite material, a thermoplastic polyurethane (TPU), or a thermoplastic elastomer (TPE). For example, the resin may include polyphenylene sulfide (PPS), polyether ether ketone (PEEK), polyimide, polyamide such as PA6 or PA66, polyamide-imide, polyphenylene sulfide (PPS), polycarbonate, polyvinyl chloride (PVC), silicone or silicone plastic, nylon, nylon 6, nylon 66, ABS, polystyrene, acrylic, engineering polyurethane, and / or other similar materials. In some embodiments, one or more parts or components of the lightweight shaft support structure may be formed from lightweight metallic materials, including but not limited to aluminum or aluminum alloys, magnesium or magnesium alloys, and / or any other suitable lightweight alloys. Any component described as being formed from a “lightweight” material in the following embodiments may include any one or a combination of the above materials.

[0074] One or more parts or components of the lightweight shaft support structure may have a density considerably lower than that of the body material. In many embodiments, the density of the lightweight material forming one or more lightweight components of the shaft support structure is about 3 g / cm³. 3 It may be less than 2.75 g / cm³. In many embodiments, the density of the lightweight material forming one or more lightweight components is 2.75 g / cm³.3 Less than 2.50 g / cm³ 3 Less than 2.25 g / cm³ 3 2.00 g / cm³ 3 Below 1.75g / cm 3 Below 1.50g / cm 3 Below 1.25g / cm 3 Below 1.00g / cm 3 Below 0.75g / cm 3 The following, or 0.50 g / cm³ 3 The following is possible: By forming a part of the shaft support structure, which would normally be made of body material, with a lightweight material, the overall mass of the shaft support structure can be reduced.

[0075] Thus, the advantages of lightweight shaft support structures are realized only when the various embodiments of shaft support structures described herein are applied to golf club heads having a body that is at least partially metal. For example, lightweight shaft support structures are applicable and beneficial in all-metal club heads or in multi-component club heads that typically include metal components that form the shaft support structure. For example, if a lightweight shaft support structure is applied to an all-component golf club head, it would not be particularly beneficial because there is no high-density body material in the shaft support structure to replace the lightweight material. Although the shaft support structures described herein are illustrated in multi-component club head bodies, it should be noted that any of the aforementioned shaft support structures can alternatively be applied to single-component or all-metal club head bodies.

[0076] A lightweight shaft support structure may be formed from a combination of body material and lightweight material. Thus, while the body material may still form certain parts of the shaft support structure, the remaining parts can be formed from separate components having lightweight material. The inclusion of lightweight material allows for discretionary mass compared to a shaft support structure formed solely from body material.

[0077] The advantage of a lightweight shaft support structure is the creation of discretionary mass that can be redistributed throughout the golf club head. A lightweight shaft support structure can create discretionary mass between 3 grams and 12 grams. In some embodiments, a lightweight shaft support structure can create discretionary mass between 3 grams and 6 grams, between 4 grams and 7 grams, between 5 grams and 8 grams, between 6 grams and 9 grams, between 7 grams and 10 grams, between 8 grams and 11 grams, or between 9 grams and 12 grams. In some embodiments, a lightweight shaft support structure can create discretionary mass greater than 3 grams, greater than 4 grams, greater than 5 grams, greater than 6 grams, greater than 7 grams, greater than 8 grams, greater than 8 grams, greater than 10 grams, greater than 11 grams, or greater than 12 grams.

[0078] Discretionary mass can be reallocated to advantageous positions on the golf club head to improve performance. Discretionary mass can be reallocated to provide a desirable CG position and / or to change the mass characteristics of the club head, such as increasing the MOI.

[0079] In many embodiments, discretionary mass resulting from the inclusion of a lightweight shaft support structure can be redistributed to provide a lower CG position (i.e., a lower CGy). In many embodiments, discretionary mass can be added to a mass pad on the sole to lower the CG position. Thus, the club head can have a substantially heavy mass pad on the sole. In many embodiments, the mass pad can have a mass between 15 grams and 40 grams. In some embodiments, the mass pad can have a mass between 15 grams and 20 grams, between 20 grams and 25 grams, between 25 grams and 30 grams, between 30 grams and 35 grams, or between 35 grams and 40 grams. In some embodiments, the mass pad can have a mass greater than 15 grams, greater than 20 grams, greater than 25 grams, greater than 30 grams, greater than 35 grams, or greater than 40 grams.

[0080] In many embodiments, discretionary mass resulting from the inclusion of a lightweight shaft support structure can lead to an increase in the MOI of the club head compared to similar club heads with prior art shaft support structures. By including the lightweight shaft support structure disclosed herein, a club head with a high MOI is provided. In many embodiments, discretionary mass can be added to a removable weight near the rear of the club head. The MOI of the club head can be increased by redistributing the mass saved by the lightweight shaft support structure to the removable weight. Thus, the club head can have a substantially heavy, removable weight near the rear. In many embodiments, the removable weight can have a mass between 1.0 gram and 35 grams. In some embodiments, the mass of the removable weight can be in the range of 1.0 gram and 20 grams, or 20 grams and 35 grams. In some embodiments, the mass of the removable weight can be in the range of 1.0 gram to 15 grams, 5 grams to 20 grams, 10 grams to 25 grams, 15 grams to 30 grams, or 20 grams to 35 grams. For example, the mass of the removable weight can be 1.0 gram, 1.5 grams, 2.0 grams, 3.0 grams, 4.0 grams, 5.0 grams, 6.0 grams, 7.0 grams, 8.0 grams, 9.0 grams, 10 grams, 11 grams, 12 grams, 13 grams, 14 grams, 15 grams, 16 grams, 17 grams, 18 grams, 19 grams, 20 grams, 21 grams, 22 grams, 23 grams, 24 grams, 25 grams, 26 grams, 27 grams, 28 grams, 29 grams, 30 grams, 31 grams, 32 grams, 33 grams, 34 grams, or 35 grams.

[0081] In many embodiments, a driver-type club head with a lightweight shaft support structure weighs 3000 g*cm². 2 From 4800g*cm 2It can have an Ixx moment of inertia between . In some embodiments, a driver-type club head with a lightweight shaft support structure has a moment of inertia of 3000 g*cm 2 and 3200g*cm 2 During this period, 3200g*cm 2 and 3400g*cm 2 During this period, 3400g*cm 2 and 3600g*cm 2 During this period, 3600g*cm 2 and 3800g*cm 2 During this period, 3800g*cm 2 and 4000g*cm 2 During this period, 4000g*cm 2 and 4200g*cm 2 During this period, 4200g*cm 2 and 4400g*cm 2 During this period, 4400g*cm 2 and 4600g*cm 2 During or 4600g*cm 2 and 4800g*cm 2 It can have an Ixx moment of inertia between these two values.

[0082] In some embodiments, a driver-type club head with a lightweight shaft support structure weighs 4500g*cm². 2 and 6000g*cm 2 It can have a moment of inertia of 1yy between . In some embodiments, a driver-type club head with a lightweight shaft support structure has a moment of inertia of 4500 g*cm 2 and 5000g*cm 2 During this period, 4600g*cm 2 and 5100g*cm 2 During this period, 4700g*cm 2 and 5200g*cm 2 During this period, 4800g*cm 2 and 5300g*cm 2 During this period, 4900g*cm 2 and 5400g*cm 2 During this period, 5000g*cm 2 and 5500g*cm 2 During this period, 5100g*cm 2 and 5600g*cm2 between 5200 g·cm 2 and 5700 g·cm 2 between 5300 g·cm 2 and 5800 g·cm 2 between 5400 g·cm 2 and 5900 g·cm 2 between, or 5500 g·cm 2 and 6000 g·cm 2 and can have a moment of inertia Iyy between them.

[0083] In some embodiments, a driver-type club head having a lightweight shaft receiving structure can have a moment of inertia Izz between 2400 g·cm 2 and 3000 g·cm 2 In some embodiments, a driver-type club head having a lightweight shaft receiving structure can have a moment of inertia Izz between 2400 g·cm 2 and 2500 g·cm 2 between 2500 g·cm 2 and 2,600 g·cm 2 between 2600 g·cm 2 and 2700 g·cm 2 between 2700 g·cm 2 and 2800 g·cm 2 between 2800 g·cm 2 and 2900 g·cm 2 between, or 2900 g·cm 2 and 3000 g·cm 2 and can have a moment of inertia Izz between them.

[0084] In many embodiments, a fairway wood-type club head having a lightweight shaft receiving structure can have a moment of inertia Ixx between 1400 g·cm 2 and 2200 g·cm 2 In some embodiments, a fairway wood-type club head having a lightweight shaft receiving structure can have a moment of inertia Ixx between 1400 g·cm 2 and 1500 g·cm 2 between 1500 g·cm 2 and 1600 g·cm 2During this period, 1600g*cm 2 and 1700g*cm 2 During this period, 1700g*cm 2 and 1800g*cm 2 During this period, 1800g*cm 2 and 1900g*cm 2 During this period, 1900g*cm 2 and 2000g*cm 2 During this period, 2000g*cm 2 and 2100g*cm 2 During or 2100g*cm 2 and 2200g*cm 2 It can have an Ixx moment of inertia between these two values.

[0085] In some embodiments, a fairway wood-type club head with a lightweight shaft support structure weighs 2800g*cm². 2 and 4000g*cm 2 It can have a moment of inertia of 1yy between . In some embodiments, a fairway wood type club head with a lightweight shaft support structure has a moment of inertia of 2900 g*cm 2 and 4000g*cm 2 During this period, 3000g*cm 2 and 3200g*cm 2 During this period, 3100g*cm 2 and 3300g*cm 2 During this period, 3200g*cm 2 and 3400g*cm 2 During this period, 3300g*cm 2 and 3500g*cm 2 During this period, 3400g*cm 2 and 3600g*cm 2 During this period, 3500g*cm 2 and 3700g*cm 2 During this period, 3600g*cm 2 and 3800g*cm 2 During this period, 3700g*cm 2 and 3900g*cm 2 During or 3800g*cm 2 and 4000g*cm 2 It can have an Iyy moment of inertia between these two points.

[0086] In some embodiments, a fairway wood-type club head with a lightweight shaft support structure weighs 1600g*cm². 2 and 2400g*cm 2 It can have an inertia moment of Izz between . In some embodiments, a fairway wood type club head with a lightweight shaft support structure has a weight of 1600 g*cm 2 and 1700g*cm 2 During this period, 1700g*cm 2 and 1800g*cm 2 During this period, 1800g*cm 2 and 1900g*cm 2 During this period, 1900g*cm 2 and 2000g*cm 2 During this period, 2000g*cm 2 and 2100g*cm 2 During this period, 2100g*cm 2 and 2200g*cm 2 During this period, 2200g*cm 2 and 2300g*cm 2 During or 2300g*cm 2 and 2400g*cm 2 It can have an inertia moment of Izz between these two points.

[0087] In many embodiments, the hybrid club head with a lightweight shaft support structure weighs 750g*cm 2 and 1000g*cm 2 It can have an Ixx moment of inertia between . In some embodiments, a hybrid club head with a lightweight shaft support structure has a moment of inertia of 750 g*cm 2 and 800g*cm 2 During this period, 800g*cm 2 and 850g*cm 2 During this period, 850g*cm 2 and 900g*cm 2 During this period, 900g*cm 2 and 950g*cm 2 During, or 950g*cm 2 and 1000g*cm 2It can have an Ixx moment of inertia between these two values.

[0088] In some embodiments, a hybrid club head with a lightweight shaft support structure weighs 2500g*cm². 2 and 3200g*cm 2 It can have a moment of inertia of 1yy between . In some embodiments, a hybrid club head with a lightweight shaft support structure has a moment of inertia of 2500 g*cm 2 and 2600g*cm 2 During this period, 2600g*cm 2 and 2700g*cm 2 During this period, 2700g*cm 2 and 2800g*cm 2 During this period, 2800g*cm 2 and 2900g*cm 2 During this period, 2900g*cm 2 and 3000g*cm 2 During this period, 3000g*cm 2 and 3100g*cm 2 During or 3100g*cm 2 and 3200g*cm 2 It can have an Iyy moment of inertia between these two points.

[0089] In some embodiments, a hybrid club head with a lightweight shaft support structure weighs 2200g*cm². 2 and 3000g*cm 2 It can have an Izz moment of inertia between . In some embodiments, a hybrid club head with a lightweight shaft support structure has a moment of inertia of 2200 g*cm 2 and 2300g*cm 2 During this period, 2300g*cm 2 and 2400g*cm 2 During this period, 2400g*cm 2 and 2500g*cm 2 During this period, 2500g*cm 2 and 2600g*cm 2 During this period, 2600g*cm 2 and 2700g*cm 2 During this period, 2700g*cm 2and 2800g*cm 2 During this period, 2800g*cm 2 and 2900g*cm 2 During or 2900g*cm 2 and 3000g*cm 2 It can have an inertia moment of Izz between these two points.

[0090] Furthermore, the discretionary mass created by including a lightweight shaft support structure allows for the repositioning of the mass to provide a more desirable CG position. In many embodiments, the discretionary mass can be repositioned to lower the CG height and / or increase the CG depth. Lowering the CG height can improve the performance characteristics of the club head by increasing the launch angle, decreasing ball spin speed, and / or improving ball speed.

[0091] In many embodiments, a driver-type club head with a lightweight shaft support structure can have a CG height between 0 inches and -0.300 inches. In some embodiments, a driver-type club head with a lightweight shaft support structure can have a CG height between 0 inches and -0.050 inches, between -0.050 inches and -0.100 inches, between -0.100 inches and -0.150 inches, between -0.150 inches and -0.200 inches, between -0.200 inches and -0.250 inches, or between -0.250 inches and -0.300 inches.

[0092] In many embodiments, a driver-type club head with a lightweight shaft support structure can have a CG depth between 1.25 inches and 2.00 inches. In some embodiments, a driver-type club head with a lightweight shaft support structure may have a CG depth between 1.25 inches and 1.75 inches, between 1.30 inches and 1.80 inches, between 1.35 inches and 1.85 inches, between 1.40 inches and 1.90 inches, between 1.45 inches and 1.95 inches, or between 1.50 inches and 2.00 inches.

[0093] In many embodiments, fairway wood-type club heads with a lightweight shaft support structure can have a CG height between -0.140 inches and -0.200 inches. In some embodiments, a fairway wood-type club head equipped with a lightweight shaft support structure may have a CG height between -0.140 inches and -0.145 inches, between -0.145 inches and -0.150 inches, between -0.150 inches and -0.155 inches, between -0.155 inches and -0.160 inches, between -0.160 inches and -0.165 inches, between -0.165 inches and -0.170 inches, between -0.170 inches and -0.175 inches, between -0.175 inches and -0.180 inches, between -0.180 inches and -0.185 inches, between -0.185 inches and -0.190 inches, between -0.190 inches and -0.195 inches, or between -0.195 inches and -0.200 inches.

[0094] In many embodiments, a fairway wood-type club head with a lightweight shaft support structure can have a CG depth between 1.00 inches and 1.50 inches. In some embodiments, a fairway wood-type club head with a lightweight shaft support structure can have a CG depth between 1.00 inches and 1.05 inches, between 1.05 inches and 1.10 inches, between 1.10 inches and 1.15 inches, between 1.15 inches and 1.20 inches, between 1.20 inches and 1.25 inches, between 1.25 inches and 1.30 inches, between 1.30 inches and 1.35 inches, between 1.35 inches and 1.40 inches, between 1.40 inches and 1.45 inches, or between 1.45 inches and 1.50 inches.

[0095] In many embodiments, a hybrid club head with a lightweight shaft support structure can have a CG height between -0.220 inches and -0.320 inches. In some embodiments, a hybrid club head with a lightweight shaft support structure can have a CG height between -0.220 inches and -0.230 inches, between -0.230 inches and -0.240 inches, between -0.240 inches and -0.250 inches, between -0.250 inches and -0.260 inches, between -0.260 inches and -0.270 inches, between -0.270 inches and -0.280 inches, between -0.280 inches and -0.290 inches, between -0.290 inches and -0.300 inches, between -0.300 inches and -0.310 inches, or between -0.310 inches and -0.320 inches.

[0096] In many embodiments, a hybrid club head with a lightweight shaft support structure can have a CG depth between 0.900 inches and 1.25 inches. In some embodiments, a hybrid club head with a lightweight shaft support structure can have a CG depth between 0.900 inches and 1.00 inches, between 0.925 inches and 1.025 inches, between 0.950 inches and 1.050 inches, between 0.975 inches and 1.075 inches, between 1.00 inches and 1.100 inches, between 1.025 inches and 1.125 inches, between 1.050 inches and 1.150 inches, between 1.075 inches and 1.175 inches, between 1.100 inches and 1.200 inches, between 1.125 inches and 1.225 inches, or between 1.150 inches and 1.250 inches.

[0097] A lightweight shaft support structure can reduce the mass of parts of the prior art shaft support structure that do not provide structural support. Referring to Figures 17A and 17B, certain parts of the prior art shaft support structure are subjected to a negligible amount of stress load during impact. Referring to Figure 17A, the highest stress occurs on the striking face near the center of the striking face during impact. As indicated by the change in the cross-hatch pattern, regions where the stress during impact gradually decreases are shown around the region of highest stress. The rear of the golf club head and the shaft support structure within the golf club head share a thinner cross-hatch pattern that indicates the region of lowest stress during impact. As shown in Figure 17B, even with the hosel tube 160 removed, the shaft support structure within the golf club head still experiences the lowest stress during impact.

[0098] Furthermore, some embodiments of the shaft support structure have portions that are not required to hold the golf shaft within the hosel bore. Referring to Figures 18A and 18B, when the shaft sleeve 166 is connected to the golf club head 100, the shaft sleeve 166 is held in place by tension due to the downward force exerted by the tightening of the threaded fastener 176. The force acting on the upper portion of the shaft sleeve 166 can be analyzed by simplifying the contact between the upper portion of the shaft sleeve 166 and the upper portion of the hosel wall 154 (closer to the hosel bore opening 158) to occur at the upper contact surface 186. The force acting on the lower portion of the shaft sleeve 166 can be analyzed by simplifying the contact between the lower portion of the shaft sleeve 166 and the lower contact surface 187. Figure 18B shows that the forces acting on the upper portion of the shaft sleeve 166 are canceled out or balanced at the upper end of the hosel wall 154 (closer to the hosel bore opening 158), without the involvement of the hosel tube 160. Figure 18B further shows that the force acting on the lower portion of the shaft sleeve 166 is offset or balanced at the hosel base 162, again without the involvement of the hosel tube 160. This indicates that the hosel tube 160 does not provide the necessary support to hold the shaft within the hosel of the golf club head 100.

[0099] Various embodiments of shaft support structures with lightweight components are described in further detail below. The different embodiments are distinguished with respect to parts of the prior art shaft support structure that are replaced by or completely removed by lightweight components. The different embodiments are further distinguished by the total amount of discretionary mass created compared to the prior art shaft support structure. In many embodiments, some or all of the mass of the hosel, hosel wall, hosel tube, and / or hosel base can be replaced with lightweight material or lightweight components. Different embodiments feature different combinations of shaft support structure parts replaced by lightweight components. Different embodiments balance the need to provide loft and lie angle adjustability, the need to seal the internal cavity, and the desire for a simple manufacturing and / or assembly process with the desire to create the maximum amount of discretionary mass. A further advantage of lightweight shaft support structures includes the removal of expensive body materials that are replaced by lightweight components. Thus, by providing lightweight shaft support structures, the manufacturing cost of club heads can be reduced.

[0100] (III. Lightweight shaft support structure with lower end cap) Figures 7-9 show a first embodiment of a wood-type golf club head featuring a lightweight, adjustable shaft support structure 250 in which a portion of the hosel tube, hosel base, and hosel wall 254 are replaced with lightweight components. Such lightweight components can be formed from materials with a lower density than the body material 201, such as the lightweight materials described above. The lightweight shaft support structure 250 can have a mass reduced by 3 to 12 grams compared to a similar shaft support structure formed entirely from the body material. By reducing the mass of the shaft support structure 250 by forming the components from lightweight materials rather than the body material, discretionary mass is ensured to be redistributed to other areas of the club head 200 in order to improve mass characteristics and performance.

[0101] Referring to Figure 7, the shaft support structure 250 comprises a lightweight tube insert 230 that replaces the entire hosel tube and a portion of the hosel wall 254. In many embodiments, the tube insert 230 is a complete cylindrical tube located within the internal cavity 207. The tube insert 230 is formed as a separate component from the hosel 252 and inserted into the internal cavity 207 during manufacturing. The tube insert 230 can extend from near the hosel bore opening 258 to the hosel base 262. The tube insert 230 reduces mass by replacing at least a portion of the mass of the hosel tube and the hosel wall 254 with a less dense material. As shown in Figure 7, the tube insert 230 can replace a portion of the hosel wall 254 so that the hosel wall 254 can be thinned. Since the tube insert 230 is located within the internal cavity 207, it replaces a large portion of the inner surface of the hosel wall 254. As shown in Figure 7, the hosel wall 254 forms the upper hosel wall 280 adjacent to the hosel bore opening 258. In many embodiments, the tube insert 230 does not form either the upper hosel wall 280 or the hosel bore opening 258. Thus, the upper hosel wall 280 can be entirely formed by the hosel 252, which is part of the club head body 201. Any receiving shape required for the adjustability of the shaft receiving structure 250 can be formed by the upper hosel wall 280. For example, in some embodiments, the upper hosel wall 280 can form one or more lobes configured to receive one or more surface features of the shaft sleeve 266 and provide adjustability for the loft angle and / or lie angle of the club head. The tube insert 230 can extend from directly below the upper hosel wall 280 to the hosel base 262.

[0102] The tube insert 230 comprises an upper end 231 adjacent to the upper part 280 of the hosel wall and a lower end 232 adjacent to the base 262 of the hosel. In many embodiments, the tube insert 230 may have a tube insert length measured parallel to the hosel bore axis 268 from the upper end 231 to the lower end 232. In many embodiments, the length of the tube insert can be between 1.00 inches and 1.50 inches. In some embodiments, the length of the tube insert can be between 1.00 inches and 1.10 inches, between 1.10 inches and 1.20 inches, between 1.20 inches and 1.30 inches, between 1.30 inches and 1.40 inches, or between 1.40 inches and 1.50 inches.

[0103] In many embodiments, the length of the tube insert 230 can be further characterized with respect to the distance between the hosel bore opening 258 and the hosel base 262 (hereinafter referred to as the "hosel length"). The hosel length can be measured parallel to the hosel bore axis 268. In many embodiments, the tube insert length can be 70% to 90% of the hosel length. In some embodiments, the tube insert length can be between 70% and 75%, between 75% and 80%, between 80% and 85%, or between 85% and 90% of the hosel length. The tube insert length is important in relation to the hosel length. If the tube insert length is too short, discretionary mass will not be maximized. However, if the tube insert length is too long, the upper end 231 of the tube insert may come too close to the hosel bore opening 258, potentially resulting in excessive stress on the tube insert 230 during impact.

[0104] To avoid compromising the structural integrity of the club head 100, the tube insert 230 can be spaced away from high-stress areas located near the hosel bore opening 258. The upper end 231 of the tube insert can be offset by a tube insert offset distance 234 from the uppermost edge of the hosel bore opening 258. The tube insert offset distance 234 can be measured parallel to the hosel bore axis 268. In many embodiments, the tube insert offset distance 234 can be in the range of 0.150 inches to 0.350 inches. In some embodiments, the tube insert offset distance 234 can be between 0.150 and 0.200 inches, between 0.200 and 0.250 inches, between 0.250 and 0.300 inches, or between 0.300 and 0.350 inches. In some embodiments, the tube insert offset distance 234 can be 0.150 inches, 0.160 inches, 0.170 inches, 0.180 inches, 0.190 inches, 0.200 inches, 0.210 inches, 0.220 inches, 0.230 inches, 0.240 inches, 0.250 inches, 0.260 inches, 0.270 inches, 0.280 inches, 0.290 inches, 0.300 inches, 0.310 inches, 0.320 inches, 0.330 inches, 0.340 inches, or 0.350 inches.

[0105] As described above with reference to Figures 17A and 17B, the stress caused by the ball impacting the striking face 202 of the golf club head 200 is highest in the impact region near the geometric center 220 of the striking face. As the distance from the impact point increases, the stress on the club head material decreases. Figures 17A and 17B illustrate that as the stress propagates through the material, it propagates mainly through the outer surface of the golf club head 200, decreases in the internal cavity 207 of the golf club head 200, and decreases towards the rear 211 of the golf club head 200. The upper end 231 of the tube insert is located away from the stress propagation. Similarly, the attachment point of the shaft sleeve 266 to the threaded fastener 276 of the hosel base 262 is also located away from the stress propagation. Therefore, the contact point between the shaft sleeve 266 and the golf club head 200 is in a region of lower stress. The tube insert 230 is located within the internal cavity 207 and is separated from the outer surface of the club head 200, thus protecting it from high stresses during impact.

[0106] In the embodiments shown in Figures 7 to 9, the hosel wall 254 is thinner compared to the upper hosel wall 280. Thus, a lip 278 is formed at the junction of the upper hosel wall 180 and the rest of the hosel wall 254. The lip 278 can be formed at the lower end of the upper hosel wall 280. The lip 278 is formed by the abrupt change in thickness between the upper hosel wall 280 and the thinner hosel wall 254. In many embodiments, the upper hosel wall 280 has a thickness greater than the thickness of the rest of the hosel wall 254 (measured from the outer surface to the inner surface of the hosel wall 254). The upper end 231 of the tube insert 230 can be configured to contact the lip 278 formed by the upper hosel wall 280 and the hosel wall 254. Therefore, the tube insert 230 extends downward from the lip 278 to the internal cavity 207 and extends to the hosel base 262.

[0107] The hosel bore opening 258 is formed by the hosel 252 itself, while the majority of the hosel bore 256 is defined by the inner surface of the tube insert 230. In many embodiments, the upper part of the hosel wall 280 forms the hosel bore opening 258 and the upper part of the hosel bore 256 (i.e., the portion of the hosel bore 256 adjacent to the hosel bore opening 258), and the tube insert 230 forms the remaining portion of the hosel bore 256. The tube insert 230 completely separates the hosel bore 256 from the rest of the internal cavity 207. The tube insert 230 is sealed at both its upper end 231 and lower end 232 by a lip 278 and a hosel base 262, respectively. The tube insert 230 completely seals the hosel bore 256 from the internal cavity 207, so that even if the shaft sleeve 266 is removed, no fragments or other particles can enter the internal cavity 207 through the hosel bore opening 258. Furthermore, the seal created by the tube insert 230 also prevents water from entering the internal cavity 207 through the hosel bore opening 258. This can be particularly important to prevent the inner surface of the club head 200 from rusting.

[0108] As described above, the tube insert 230 is formed of a lightweight material having a density lower than that of the body material. Replacing the tube portion and part of the hosel wall 254 with the lightweight tube insert 230 reduces the mass of the shaft support structure 250 compared to a similar structure formed entirely of the body material. Having the lightweight tube insert 230 provides a structure for holding the shaft and shaft sleeve 266 within the hosel bore 256 and sealing the hosel bore 256 from the internal cavity 207, creating discretionary mass that can be redistributed to advantageous positions to improve the mass characteristics of the club head 200.

[0109] As described above, the lower end 232 of the tube insert 230 connects to the hosel base 262, forming a seal. In the illustrated embodiments shown in Figures 7 to 9, the hosel base 262 is formed by a lightweight, removable end cap 240. The end cap 240 can be formed as a separate component from both the club head body 201 and the tube insert 230. When fully assembled, the end cap 240 covers the lower end 232 of the tube insert 230, closing the lower opening 274 and holding the tube insert 230 in place within the internal cavity 207.

[0110] The end cap 240 can be made of a lightweight material (the lightweight material described above and the relevant densities defined above can be applied to the end cap 240). In some embodiments, the material of the end cap 240 can be the same as the material of the tube insert 230. In other embodiments, the end cap 240 and the tube insert 230 can be made of different lightweight materials.

[0111] In some embodiments, as illustrated in Figure 9, the end cap 240 may have one or more alignment features configured to receive and center the tube insert 230 relative to the end cap 240, and to fix the tube insert 230 in place. In some embodiments, as illustrated in Figure 9, the end cap 240 may have one or more notches 242 configured to receive the lower end 232 of the tube insert 230. In some embodiments, as illustrated in Figure 9, the end cap 240 may further include a projection 243 extending upward from the end cap body 241 into the hosel bore 256. The projection 243 may be shaped to be flush with the inner surface of the tube insert 230, aligning the end cap 240 with the hosel bore 256 formed within the tube insert 230. The end cap 240 may further include an opening 248 extending through the end cap body 241 from the lower surface to the upper surface in the direction of the hosel bore 256. The opening 248 is configured to receive a fastener 276 for connecting the shaft sleeve 266. In some embodiments, the opening 248 may or may not be threaded to accommodate the threaded fastener 276.

[0112] By forming the hosel base 262 with a removable end cap 240, the tube insert 230 does not need to be inserted from above through the hosel bore opening 258, but can be inserted into the internal cavity 207 through the lower opening 274. Referring to Figures 7 and 8, the tube insert 230 can be inserted through the lower opening 274 such that the upper end 231 of the tube insert 230 contacts the lip 278 of the hosel 252. The tube insert 230 can be held in place within the internal cavity 207 by either mechanical or adhesive means. In some embodiments, the tube insert 230 is held in place by the surrounding structure. As shown in Figure 7, the upper end 231 of the tube insert is restrained from above by the lip 278, from the inside by the shaft sleeve 266, and from the outside by the hosel wall 254 below the lip 278. The lower end of the tube insert is restrained from below by the hosel base 262, from the outside by the end cap 240, and from the inside by the bottom lap joint 238.

[0113] In many other embodiments, the tube insert 230 can be held in place by adhesive means. In such embodiments, the shaft support structure 250 can form multiple lap joints near the lower end 232 and upper end 231 of the tube insert 230. Figure 7 illustrates a bottom lap joint 238 formed by the club head body 201 between the lower end 232 of the tube insert 230 and the hosel base 262, and a top lap joint 236 formed between the upper end 231 of the tube insert 230 and the interior of the hosel 252 near the lip 278. The top lap joint 236 can be formed by the inner surface of the hosel wall 254 adjacent to the lip 278. The bottom lap joint 238 can extend upward from the hosel base 262 (formed by the end cap 240) and enter into the internal cavity 207. The bottom lap joint 238 can be configured such that its inner surface corresponds to the tube insert 230 and provides a surface for the tube insert 230 to adhere to. The tube insert 230 and the club head body 201 can be bonded by epoxy or other means at both the top lap joint 236 and the bottom lap joint 238 so that the tube insert 230 remains fixed in place even when the fastener 276 is loosened and the shaft sleeve 266 is removed.

[0114] By inserting the tube insert 230 through the lower opening 274, the manufacturing and assembly processes can be simplified. Since it is not necessary to insert the tube insert 230 through the hosel bore opening 258, the upper hosel wall 280 and the hosel bore opening 258 can be formed integrally with the rest of the hosel 252. Without the ability to insert the tube insert 230 through the lower opening 274, the upper hosel wall 280 and the hosel bore opening 258 would need to be formed separately from the rest of the hosel 252 and connected to enclose the upper end 231 of the tube insert 230. Therefore, the shaft support structure 250, which can receive the tube insert 230 through the lower opening 274, allows the shape of the hosel 252, including the receiving shape configured to receive the shaft sleeve 266, to be cast integrally as a single piece.

[0115] As described above, the mass of the shaft support structure is reduced by including lightweight components to replace part of the shaft support structure. In some embodiments, the lightweight shaft support structure generates discretionary mass of 3 to 12 grams. The discretionary mass generated by the lightweight shaft support structure can be distributed throughout the club head to improve mass characteristics and performance.

[0116] (IV. Lightweight shaft support structure with lightweight collar) Figures 10 to 12 show a second embodiment of the club head 300, which includes a lightweight shaft support structure 350 in which the hosel tube and a portion of the hosel wall 354 (specifically the upper part of the hosel wall) are replaced with a lightweight material. The shaft support structure 350 has a tube insert 330 similar to that of the first embodiment 200, which can be inserted from the top rather than from the bottom opening 374. Rather than a one-piece hosel in which the entire hosel wall (including the upper part of the hosel wall) is integrally formed as part of the club head body 301, the second embodiment of the shaft support structure 350 has a lightweight collar 386 formed separately from the rest of the hosel 352 instead of the upper part of the hosel wall. The collar 386 can be connected to the hosel wall 354 to create a two-piece hosel 352. The collar 386 can be connected to the top of the hosel wall 354 so that the collar 386 forms the upper part of the two-piece hosel 352.

[0117] The collar 386 is configured to interact with the shaft sleeve 366. The collar 386 forms the hosel bore opening 358. In many embodiments, the collar can form a receptive shape configured to receive the shaft sleeve 366. For example, in some embodiments, the hosel collar 386 can form one or more lobes configured to receive one or more surface features of the shaft sleeve 366 and to provide adjustability for the loft angle and / or lie angle of the club head. Thus, the collar 386 is configured to receive and hold the shaft sleeve 366 in place. As shown in Figure 10, the collar 386 forms a lip 378 that acts as a lap joint 336 for connecting and / or securing the tube insert 330 within the internal cavity 307. The lip 378 can be positioned just below the collar 386. When inserted, the upper end 331 of the tube insert 330 contacts the lip 378. The tube insert 330 is inserted from the top of the club head 300 through a hosel wall opening 359 formed by the upper edge 355 of the hosel wall 354, and can then be covered by the collar 386.

[0118] The hosel wall 354 and the collar 386 can be connected by a joint formed between the upper edge 355 of the hosel wall 354 and the lower edge 388 of the collar 386. In many embodiments, the hosel wall 354 and the collar 386 have a mating shape configured to facilitate connection of the collar 386 to the hosel wall 354 by mechanical interlock and / or adhesive. In some embodiments, as shown in Figure 12, the hosel wall 354 has a plurality of teeth 391 extending upward from the upper edge 355 of the hosel wall. The collar 386 may have a plurality of recesses 390 formed in the lower edge 388 of the collar that mate in accordance with the shape of the plurality of teeth 391. The plurality of teeth 391 are configured to mate within the plurality of recesses 390, allowing the collar 386 to be connected to the hosel wall 354. The collar 386 can be fixed in place using epoxy resin or additional mechanical fasteners.

[0119] In some embodiments, the collar 386 has a lightweight material as defined above. In many embodiments, the collar 386 is formed of a lightweight metallic material having a density lower than that of the metal body 301. In many embodiments, the collar 386 is provided by a lightweight metal because it is located at the upper end of the hosel 352, which is typically subjected to higher stress than other parts of the shaft support structure 350. For example, in some embodiments, the collar 386 can be formed of aluminum, aluminum alloy, titanium, titanium alloy, magnesium, or magnesium alloy. In many embodiments, the collar 386 is formed of a metallic material similar to that of the shaft sleeve 366. Having both the collar 386 and the shaft sleeve 366 made of similar metals prevents wear between any of the receiving shapes of each component.

[0120] The shaft support structure 350 having the collar 386 further comprises a lightweight tube insert 330 which is identical or substantially identical to the tube insert 230 described above in relation to the club head 200. The upper end 331 of the tube insert 330 is in contact with the lip 378 formed by the collar 386 and extends downward toward the hosel base 362 and the lower opening 374. Similar to the first embodiment, the tube insert 330 forms most of the hosel bore 356 and seals the hosel bore 356 from the rest of the internal cavity 307.

[0121] In addition to replacing the mass of the hosel tube with a lightweight tube insert 330, the mass of the shaft support structure 350 is further reduced by replacing the body material on the upper part of the hosel wall with a lightweight collar 386. The mass replacement via the lightweight tube insert 330 and the collar 386 creates discretionary mass that is redistributed throughout the club head 300. In some embodiments, the lightweight shaft support structure 350, including the tube insert 330 and the collar 386, can generate discretionary mass of 3 to 12 grams.

[0122] Similar to the tube insert 230 described above, the upper end 331 of the tube insert 330 can be offset from the uppermost end of the hosel bore opening 358 by a tube insert offset distance 334. The tube insert offset distance 334 can be measured parallel to the hosel bore axis 368. In many embodiments, the tube insert offset distance 334 can be in the range of 0.150 inches to 0.350 inches. In some embodiments, the tube insert offset distance 334 can be between 0.150 and 0.200 inches, between 0.200 and 0.250 inches, between 0.250 and 0.300 inches, or between 0.300 and 0.350 inches. In some embodiments, the tube insert offset distance 334 can be 0.150 inches, 0.160 inches, 0.170 inches, 0.180 inches, 0.190 inches, 0.200 inches, 0.210 inches, 0.220 inches, 0.230 inches, 0.240 inches, 0.250 inches, 0.260 inches, 0.270 inches, 0.280 inches, 0.290 inches, 0.300 inches, 0.310 inches, 0.320 inches, 0.330 inches, 0.340 inches, or 0.350 inches.

[0123] As described above with reference to Figures 17A and 17B, the stress caused by the ball impacting the striking face 302 of the golf club head 300 is highest in the impact region near the geometric center 320 of the striking face. As the distance from the impact point increases, the stress on the club head material decreases. Figures 17A and 17B illustrate that as the stress propagates through the material, it propagates mainly through the outer surface of the golf club head 300, decreases in the internal cavity 307 of the golf club head 300, and decreases towards the rear 311 of the golf club head 300. The upper end 331 of the tube insert is located away from stress propagation. Similarly, the attachment point of the shaft sleeve 366 to the threaded fastener 376 of the hosel base 362 is also located away from stress propagation. Therefore, the contact point between the shaft sleeve 366 and the golf club head 300 is in a region of lower stress. The tube insert 330 is located within the internal cavity 307 and is separated from the outer surface of the club head 300, thus protecting it from the high stresses during impact.

[0124] In many embodiments, such as those shown in Figures 10-12, the hosel base 362 of the second embodiment can be integrated with the club head body 301, rather than forming a separate end cap. The hosel base 362 can be cast as part of the body 301, close to the lower opening 374. The hosel base 362 extends across the lower opening 374, separating the exterior of the club head 300 from the internal cavity 307 near the sole 312. Similar to the end cap 240 of the first embodiment, the hosel base 362 forms a platform configured to receive the lower end 332 of the tube insert 330 and hold the tube insert 330 in place. In some embodiments, the hosel base 362 may have one or more alignment features configured to center the tube insert 330 relative to the hosel base 362. In some embodiments, as shown in Figure 10, the hosel base 362 may include a projection 343 extending upward from the hosel base 362 into the hosel bore 356. The projection 343 may be shaped flush with the inner surface of the tube insert 330, aligning the tube insert 330 with the hosel base 362. As shown in Figure 11, the hosel base 362 further includes an opening 348 extending into the hosel bore 356. The opening 348 is configured to receive a fastener 376 for securing the shaft sleeve 366 within the hosel bore 356. In some embodiments, the opening 348 may be threaded to accommodate the threaded fastener 376. The hosel base 362 seals the lower opening 374 and holds the tube insert 330 in place within the internal cavity 307. In other embodiments (not shown), a club head 300 equipped with a shaft support structure 350 having a collar 386 can be combined with an end cap similar to the end cap 240 of the club head 200.

[0125] The tube insert 330 can be held in place within the internal cavity 307 by mechanical means and / or adhesive means. In some embodiments, the tube insert 330 is held in place by the surrounding structure. As shown in Figures 10 and 11, the upper end 331 of the tube insert is constrained from above by the lip 378, from the inside by the shaft sleeve 366, and from the outside by the hosel wall 354 below the lip 378. The lower end of the tube insert is constrained from below by the hosel base 362 and from the inside by the projection 343.

[0126] In many embodiments, the tube insert 330 can be held in place by adhesive means. In such embodiments, the shaft support structure 350 can form a plurality of lap joints near the lower end 332 and upper end 331 of the tube insert 330. Figure 10 illustrates a bottom lap joint 338 formed by the hosel base 362 and a top lap joint 336 formed by combining at least a portion of the hosel wall 354 and at least a portion of the collar 386. The tube insert 330 and the club head 300 can be epoxy bonded together at both the top and bottom lap joints so that the hosel insert remains fixed in place even if the fasteners are loosened and the shaft sleeve is removed.

[0127] As described above, by providing a separate collar 386 to the hosel 352 and replacing the upper part of the hosel wall, the collar 386 can be formed from a lighter material than the hosel 352, thereby further reducing the mass of the shaft support structure 350. By including the lightweight tube insert 330 and the lightweight collar 386, the mass of the shaft support structure 350 is reduced compared to the prior art shaft support structure formed from body material. In some embodiments, by replacing the lightweight tube insert 330 and the collar 386 with a higher density material, the mass of the shaft support structure 350 can be reduced by 3 to 12 grams. The reduction in the mass of the shaft support structure 350 ensures discretionary mass that can be distributed throughout the club head 300 to improve mass characteristics and performance.

[0128] (Lightweight shaft support structure with V-hosel insert) Figures 13 and 14 show a golf club head 400 of another embodiment of the lightweight shaft support structure 450. The lightweight shaft support structure 450 comprises a hosel tube and a lightweight hosel insert 430 that forms the entire hosel wall 454. The shaft support structure 450 has a hosel insert 430 made of lightweight material (as defined above). As shown in Figure 13, the body 401 forms a hosel transition section 464 that connects the crown 410 to the hosel wall 454, but does not form the hosel wall 454 beyond the hosel transition section 464. Instead, the body 401 forms a hosel transition opening 465 at the upper end of the hosel transition section 464. The hosel insert 430 can be inserted into the hosel transition opening 465 and connected to the hosel transition section 464. The hosel insert 430 is located outside the internal cavity 407 and forms a wall portion 435 visible from the outside of the club head 400, and an internal tube portion 437 that extends into the internal cavity 407 and seals the hosel bore 456 from the rest of the internal cavity 407. The wall portion 435 extends upward from the hosel transition portion 464. Thus, the inner surface of the wall portion 435 defines the upper part of the hosel bore 456. The wall portion 435 forms the entire hosel wall, including the hosel bore opening 458. Thus, the wall portion 435 is configured to receive the shaft sleeve 466 through the hosel bore opening 458. The wall portion 435 can also form any receiving shape configured to receive the shaft sleeve 466. Such shapes can be formed on the inner surface of the wall portion 435.

[0129] The hosel insert 430 further includes a tube portion 437 that extends downward from the bottom of the wall portion 435 through the hosel transition opening 465 toward the hosel base 462. The inner surface of the tube portion 437 forms the lower part of the hosel bore 456. The tube portion 437 seals the hosel bore 456 from the outside of the club head 400 away from the internal cavity 407, preventing debris, particles, and water from entering the internal cavity 407 through the opening of the hosel bore 456.

[0130] The hosel insert 430 is generally a tubular hollow member, with an outer diameter and an inner diameter defined by its outer and inner surfaces, respectively. The outer diameter of the hosel insert 430 can vary along different portions of the hosel insert 430. As shown in Figure 13, the outer diameter of the wall portion 435 is substantially larger than the outer diameter of the tube portion 437. The diameter of the hosel insert 430 changes abruptly at the hosel transition opening 465, clearly defining the position where the wall portion 435 ends and the tube portion 437 begins. The abrupt change in diameter creates a ledge 478 separating the wall portion 435 and the tube portion 437. The ledge 478 is in contact with the upper edge of the hosel transition portion 464. The outer diameter of the wall portion 435 at the hosel transition opening 465 can coincide with the diameter of the hosel transition opening 465 at its upper edge. In this way, the hosel transition portion 464 and the wall portion 435 form a smooth continuous surface between them, resembling a single, integrally formed hosel. The outer diameter of the tube section 437, which is smaller in diameter than the hosel transition section 464, is large enough to extend through the hosel transition opening 465 into the internal cavity. Because the outer diameter of the wall section 435 is relatively large and the outer diameter of the tube section 437 is relatively small, the hosel insert 430 can replace as much mass as possible with lightweight material. Internally, the hosel insert 430 replaces the mass of the hosel tube, and externally, the hosel insert 430 replaces the hosel wall 454 with lightweight material to create discretionary mass.

[0131] In some embodiments, the hosel transition section 464 may further include a joining wall 461 within the internal cavity 407, configured to centralize the tube portion 437 and provide a surface for the hosel insert 430 to join. The joining wall 461 may be a cylindrical wall integrally formed with the hosel transition section 464. The joining wall 461 extends at least partially from the hosel transition opening 465 toward the hosel base 462. The joining wall 461 has an inner diameter corresponding to the outer diameter of the tube portion 437. The tube portion 437 of the hosel insert 430 is in close contact with the joining wall 461. Thus, the joining wall 461 functions as a lap joint that can fix the hosel insert 430 within the internal cavity 407 and position it centrally.

[0132] In the third embodiment, the club head 400 further forms a hosel base 462 that forms a floor for the hosel insert 430, and the lower end of the hosel tube portion 437 is configured to contact the hosel base 462. The lower end of the hosel insert 430 (i.e., the lower end of the hosel tube portion 437) can be supported on the hosel base 462. The hosel base 462 in the third embodiment may be substantially similar to the integrally molded hosel base 462 in the second embodiment. The hosel base 462 is cast integrally with the club head body 401 and can close the lower opening 474 to separate the outside of the club head from the internal cavity 407 near the sole. As shown in Figure 14, the hosel base 462 has an opening 448 that can provide a passage in the hosel bore 456 for a fastener 476 to connect to the shaft sleeve 466. In some embodiments, the hosel base 462 may have one or more alignment features configured to center the hosel insert 430 relative to the hosel base 462. In some embodiments (not shown), a club head 400 having a shaft support structure 450 with a hosel insert 430 can be combined with an end cap similar to the end cap 240 of the club head 200.

[0133] The hosel insert 430 can be held within the shaft support structure 450 by mechanical and / or adhesive means. In many embodiments, the hosel insert 430 is held in place by restraining forces generated by the fastener 476, the shaft sleeve 466, and the hosel base 462. As shown in Figure 14, the fastener 476 extends through the lower opening 474 and connects to the lower end of the shaft sleeve 466. The shaft sleeve 466 is inserted through the hosel bore opening 458, and the fastener 476 is inserted through the opening 448 of the hosel base 462, so the fastener 476 and the shaft sleeve 466 hold the hosel insert 430 in a compressed state, generating opposing forces. Specifically, the fastener 476 presses the shaft sleeve 466 downward against the hosel insert 430, thereby pressing the hosel base 462 downward. The restraining force generated between the fastener 476 and the shaft sleeve 466 holds the hosel insert 430 in place within the internal cavity 407.

[0134] In many other embodiments, the hosel insert 430 can be held in place by adhesive means. In such embodiments, the shaft support structure 450 can form a number of lap joints configured to connect the hosel insert 430 to the club head body 401 via the use of adhesive or epoxy. Figure 13 shows a lap joint 436 formed between the tubular portion 437 and the joint wall 461. The hosel insert 430 and the club head 400 can be joined at the lap joint 436 with epoxy resin or other adhesive such that the hosel insert 430 remains fixed in place even if the fastener 476 is loosened and the shaft sleeve 466 is removed.

[0135] By including a lightweight hosel insert 430, the mass of the shaft support structure 450 is reduced compared to a similar structure formed solely from the body material. In some embodiments, including a lightweight hosel insert 430 instead of a denser material reduces the mass of the shaft support structure 450 by 3 to 12 grams. This mass reduction of the shaft support structure 450 ensures that there is discretionary mass that can be distributed throughout the club head 400 to improve mass characteristics and performance.

[0136] The hosel insert 430 forms the outer portion of the hosel 452. Since the hosel insert 430 extends to the hosel bore opening 458, it may be subjected to greater stress during impact than the hosel tube inserts 230 and 330 of previous embodiments, and therefore it may be advantageous to provide the hosel insert 430 from a material having higher strength than composite materials. In many embodiments, the hosel insert 430 can be made of a lightweight metallic material rather than a non-metallic material. In some embodiments, the hosel insert 430 can be formed from aluminum, an aluminum alloy, or any lightweight metallic material with a density lower than that of the body material. By providing the hosel insert 430 from a lightweight metal, the mass of the shaft support structure 450 can be reduced (because the lightweight metal has a lower density than the body material), while still maintaining the structural integrity of the club head 400.

[0137] (VI. Tubeless lightweight shaft support structure) Figure 15 shows another embodiment of the lightweight shaft support structure 550 without a tube insert (hereinafter referred to as the "tubeless" shaft support structure 550). In the embodiment shown in Figure 15, the hosel tube of the prior art design is completely eliminated. Therefore, the shaft sleeve 566 is not hidden within the tube portion or tube insert. Thus, at least a portion of the shaft sleeve 566 is exposed to the internal cavity 507. In many embodiments, at least a portion of the outer wall 567 of the shaft sleeve is exposed to the internal cavity 507. The tubeless shaft support structure 550 is formed entirely of body material and can have a mass reduced by 3 to 12 grams compared to a similar shaft support structure with a hosel tube. The tubeless shaft support structure 550 can further comprise one or more components that can form other parts of the club head 500 that were formed of body material in the prior art, such as the hosel base 562. Reducing the mass of the shaft support structure 550 by eliminating the hosel tube and forming other components with lightweight materials instead of body material ensures discretionary mass that can be redistributed to other areas of the club head 500 to improve mass characteristics and performance.

[0138] The tubeless shaft support structure 550 may be substantially similar to the shaft support structure 250 shown in Figures 7 to 9, but the tubeless shaft support structure 550 does not have a tube insert (such as the tube inserts 230, 330, etc. in previous embodiments). The tubeless shaft support structure 550 comprises a hosel 552 and a shaft sleeve 566. The hosel 552 forms a hosel wall 554, and the upper part of the hosel wall 580 forms a hosel bore opening 558 configured to receive the shaft sleeve 566.

[0139] The shaft support structure 550 further includes an end cap 540 that forms the hosel base 562. The end cap 540 can be formed as a separate component from the club head body 101. The end cap 540 is provided to form the hosel base 562 from a lightweight material, rather than forming the hosel base from the body material, as is common in the prior art. In many embodiments, the end cap 540 can be substantially similar to the end cap 240. The end cap 540 can be configured to close the lower opening 574.

[0140] As shown in Figure 15, the shaft support structure 550 further includes a base wall 561 extending from the lower opening 574 into the internal cavity 507. The bottom of the hosel base wall 561 can form a ledge 578, and the end cap 540 is configured to contact the ledge 578. The end cap 540 can be shaped to cover the entire lower opening 574, separating the outside of the club head 500 from the internal cavity 507.

[0141] Because there is no tube insert or hosel tube, the tubeless shaft support structure 550 does not have a continuous hosel bore. In other words, the tubeless shaft support structure 550 does not have a hosel bore extending from the hosel bore opening 558 to the hosel base 562. As shown in Figure 15, the shaft support structure 550 comprises an upper hosel bore 556a and a lower hosel bore 556b separate from the upper hosel bore 556a. The upper hosel bore 556a can be formed by the inner surface of the upper hosel wall 580. In many embodiments, the upper hosel bore 556a can extend from the hosel bore opening 558, formed by the upper edge of the upper hosel wall 580, to the bottom of the upper hosel wall 580. In other embodiments, a portion of the upper hosel bore 556a can be formed by the hosel wall 554. The upper hosel bore 556a can transition abruptly or gradually into the internal cavity 507. The upper hosel bore 556a transitions into the internal cavity 507 as the hosel wall 554 branches off from the shaft sleeve 566. The lower hosel bore 556b can be formed by the inner surface of the hosel base wall 561. The lower hosel bore 556b extends from the lower opening 574 to the top of the hosel base wall 561. Similar to the upper hosel bore 556a, the lower hosel bore 556b leads directly into the internal cavity 507.

[0142] There is no structure connecting the upper hosel bore 556a and the lower hosel bore 556b. The upper hosel bore 556a and the lower hosel bore 556b each lead to the internal cavity 507 independently. The upper hosel bore 556a and the lower hosel bore 556b do not communicate with each other. The shaft sleeve 566 extends through the gap 557 formed between the upper hosel bore 556a and the lower hosel bore 556b, thereby exposing the shaft sleeve 566 to the internal cavity 507.

[0143] The tubeless shaft support structure 550 can be held together by a fastener 576, a shaft sleeve 566, and an end cap 540. The shaft sleeve 566 is inserted into the upper hosel bore 556a through a hosel bore opening 558 and is configured to contact the upper part of the hosel wall 580. The fastener 576 is inserted into the lower hosel bore 556b through an opening 548 formed in the end cap 540 and is configured to contact the outer surface of the end cap 540. When tightened, the fastener 576 presses against the outer surface of the end cap 540, applying a restraining force to the shaft sleeve 566. When the fastener 576 and the shaft sleeve 566 are securely connected, they create a restraining force that holds the components of the shaft support structure 550 together. The fastener 576 generates an upward force pushing against the end cap 540, and the shaft sleeve 566 generates an opposite downward force against the inner surface of the upper part of the hosel wall 580. Thus, the shaft sleeve 566 is held within the upper hosel bore 556a by a downward tensile force acting on the shaft sleeve 566. The restraining force between the fastener 576 and the shaft sleeve 566 holds the components of the shaft support structure 550 in place.

[0144] The tubeless shaft support structure 550 provides the maximum amount of discretionary mass to be redistributed to the club head 500. Because the hosel tube is completely removed, the tubeless shaft support structure 550 has a minimal structure. Furthermore, by including a separate tube insert, the tubeless shaft support structure 550 does not reintroduce any mass, even very small amounts. The tubeless shaft support structure 550 can be advantageous for inclusion in the club head 500 where maximum discretionary mass is desired over the ability to seal the internal cavity 507.

[0145] (VII. Lightweight shaft support structure with external hosel insert) Figure 16 shows another embodiment of the lightweight shaft support structure 650 in which a portion of the hosel wall 654 is replaced and a portion of the hosel transition 664 is formed by a hosel insert 630 made of a lightweight material (as defined above). In many embodiments, the hosel wall 654 and the hosel transition 664 can be formed together as a single insert 630 configured to connect to the club head body 601 in the crown 610. In such embodiments, the club head 600 can have a hosel transition opening 665 formed near the heel side of the crown 610. The hosel insert 630 can be configured to connect to the club head body 601 at the outer periphery of the hosel transition opening 665. In many embodiments, the hosel insert 630 can be attached to the club head body 601 at the hosel transition opening 665 by mechanical means and / or adhesive means. In some embodiments, the hosel insert 630 can have a mating shape in the hosel transition 664 configured to connect to a corresponding mating shape formed on the outer periphery of the hosel transition opening 665. The hosel insert 630 may have any receiving shape configured to form a hosel bore opening 658 and connect the shaft sleeve 666 within the hosel bore 656. For example, in some embodiments, the hosel insert 630 may receive one or more surface features of the shaft sleeve 666 and form one or more lobes configured to provide adjustability for the loft angle and / or lie angle of the club head.

[0146] The hosel insert 630 has an inner surface with an inner diameter that defines at least the upper part of the hosel bore 656. In many embodiments, the inner surface of the hosel 652 defines a portion of the hosel bore 656 extending from the hosel bore opening 658 to the hosel transition opening 665. In many embodiments, as shown by Figure 16, the lightweight hosel insert 630 is located only externally and does not extend through the hosel transition opening 665 or into any part of the internal cavity 607. The internal parts of the shaft support structure 650 (i.e., the tube portion 660, the hosel base 662, etc.) can be cast integrally with the rest of the club head body 601. Thus, the tube portion 660, separate from the lightweight hosel insert 630, forms the lower part of the hosel bore 656 extending from the hosel transition opening 665 to the hosel base 662. Because the tube section 660 and the hosel base are formed from a high-strength body material, the shaft support structure 650 is designed to withstand any stress that occurs near the sole 612.

[0147] In some embodiments, the lightweight hosel and hosel transition 664 can be formed integrally with a part of the club head body 601, rather than being formed as a separate insert and attached to the crown via mechanical or adhesive means. This configuration is applicable to club heads having a multi-material structure with a lightweight non-metallic component that forms a large portion of the crown 610, such as a crown insert made from a composite material. The lightweight hosel insert 630 and hosel transition 664 can function as an extension of the crown 610, extending upward from the crown 610 at the heel end, forming the hosel transition 664 and hosel wall 654. In such embodiments, since the hosel wall 654 and hosel transition 664 are formed integrally with the composite crown 610, the material of the hosel wall 654 and hosel transition 664 can be the same as the material of the composite crown 610. The integrated hosel wall 654 and hosel transition 664 can be formed in combination with any variation of the composite crown described in detail above, such as the composite crown 610 that wraps around the skirt 614 and forms part of the sole 612 on the heel 604 and / or toe 606.

[0148] Replacing the hosel wall 654 and hosel transition 664 with lightweight material reduces the mass of the shaft support structure 650 compared to a similar structure formed entirely from body material, whether it is formed integrally with the composite crown 610 of a multi-material club head or as a separate insert connected at the hosel transition opening 665. In some embodiments, by including a hosel insert 630, replacing the hosel wall 654 and forming the hosel transition 664 from lightweight material reduces the mass of the shaft support structure 650 by 3 to 12 grams. The reduction in the mass of the shaft support structure 650 ensures discretionary mass that can be distributed throughout the club head 600 to improve mass characteristics and performance.

[0149] (example) (Example 1: Stress distribution in a golf club head in a lightweight shaft support structure) As described above, the prior art shaft support structure surprisingly includes parts such as the hosel tube 160 that do not significantly contribute to the structural integrity of the golf club head. After an analysis was conducted showing that the stress on the hosel tube 160 is so low, experiments were conducted to determine whether the hosel tube could be simply removed or replaced with a lighter material to provide discretionary mass.

[0150] Figures 17A and 17B illustrate the peak stresses during impact between a golf club head and a golf ball. Figure 17A illustrates the peak stress of a prior art golf club head 100 having a hosel tube 160 made of the same material as the club head body 101. The finite element analysis shown in Figure 17A shows that the hosel tube 160 experiences negligible stress during impact. Negligible stress is defined as a stress less than 50% of the material fracture load. This means that the hosel tube 160 is not subjected to a large structural load. It was unexpected that the hosel tube 160 would experience such low stress during impact and not contribute significantly to the structural integrity of the club head 100.

[0151] To enlarge the analysis illustrated in Figure 17A, the hosel tube 160 was removed, and the otherwise identical club head 100 was modeled. Figure 17B illustrates the peak stress of the golf club head 100 without the hosel tube 160, with the shaft sleeve 166 exposed in the internal cavity 107. The analysis of the golf club head without the hosel tube 160 showed that the modified shaft support structure still experiences very low levels of stress at impact.

[0152] At the peak stress during impact, the striking face 102, crown return portion 122, and sole 112, which are close to the leading edge 103, absorb the impact force and experience significant stress. These parts require high-strength body material to avoid damage from impact. In contrast, the hosel tube 160, shown in Figure 17A, experiences almost no impact force during ball impact. As mentioned above, this allows the hosel tube to be completely removed or replaced with a lower-density and lower-strength material. As shown in Figure 17B, the hosel tube 160 can be removed, and the exposed shaft sleeve 166 experiences almost no stress from impact. This indicates that the hosel tube 160 is unnecessary in terms of the durability of the golf club head when impacting a golf ball.

[0153] The portion of the golf club head 100 that is close to the hosel 152 and located within the internal cavity 107 of the club head 100 experiences lower stress at impact compared to the striking face 102, crown return 122, and sole 112, which are close to the leading edge 103 of the golf club head 100. Other low-stress areas are located further away from the striking face 102. The low-stress portion of the club head 100 that is close to the hosel 152 and located within the internal cavity 107 of the golf club head can be replaced without compromising the durability of the club head at impact. As described above, most of the impact force received by the shaft support structure 150 occurs near the upper contact surface 186 and the lower contact surface 187 (shown in Figures 18A and 18B). The further away from the upper contact surface 186 and the lower contact surface 187, the less stress the shaft support structure 150 experiences, and the less mass is required to structurally support the club head 100. The mass can be reduced from the portion of the shaft support structure 150 that is away from the upper contact surface 186 and the lower contact surface 187. In many embodiments, the mass can be reduced from the portion of the shaft support structure that is a certain distance away from the hosel bore opening 158, which will be described later in relation to the tube insert offset distance.

[0154] The analysis shown in Figures 17A and 17B indicates that, from a durability standpoint, the hosel tube 160 can be formed from any lightweight material or removed entirely. To maximize discretionary mass, it is desirable to provide a hosel tube formed from the lightest possible material, or to remove it entirely, depending on the desired functionality. For example, in some embodiments, it may be desirable to maintain a lightweight hosel tube in the form of a tube insert (tube inserts 230, 330, etc.) for purposes other than receiving loads, such as sealing the internal cavity 107 from the hosel bore 156 or holding the shaft sleeve 166 in place. In other embodiments, no function other than receiving loads may be desired for the hosel tube 160, and the hosel tube 160 may be removed entirely. This is the case with the shaft support structure 550 detailed above. Examples of such club heads will be discussed later.

[0155] (Example 2: Mass characteristics of a club head equipped with a lightweight shaft support structure) The mass characteristics of several exemplary club heads equipped with a lightweight shaft support structure were compared with a control club head. The MOI values ​​of each club head were compared. Furthermore, the amount of discretionary mass resulting from including the lightweight shaft support structure in each exemplary club head was compared relative to the control club head. Each club head was constructed similarly except for the differences in the shaft support structure.

[0156] The first exemplary club head was a fairway wood-type club head with a lightweight shaft support structure similar to that of shaft support structure 250. The first exemplary club head had a lightweight tube insert that formed the hosel tube and a lightweight lower end cap that formed the base of the hosel. The tube insert was inserted into the internal cavity from the lower opening. The end cap covered the lower opening and surrounded the tube insert within the internal cavity.

[0157] The second exemplary club head was a fairway wood-type club head with a lightweight shaft support structure similar to that of the shaft support structure 550. The second exemplary club head had a tubeless design. The second exemplary embodiment did not have a tube insert. The club head comprised an upper hosel bore formed by the inner surface of the upper part of the hosel wall and a lower hosel bore formed by the inner surface of the hosel base wall. The upper and lower hosel bores were not connected and both led to an internal cavity. Therefore, when a shaft sleeve was inserted, the outer wall of the shaft sleeve was exposed to the internal cavity. The second exemplary club head had a lightweight end cap that formed the hosel base and covered the lower opening.

[0158] The control club head was a prior art fairway wood type club head having a prior art shaft support structure similar to that of shaft support structure 150. The control club head included a hosel, hosel tube, and hosel base, each integrally formed with the club head body and made from the body material. The shaft support structure of the control club head did not have any lightweight components.

[0159] Table 1 below shows the CG position for each exemplary club head and the control club head. The discretionary mass value represents how much mass is saved compared to the control club head by incorporating a lightweight shaft support structure into each exemplary club head. [Table 1]

[0160] As is evident from Table 1, the exemplary clubhead exhibits an increase in discretionary mass. Here, the discretionary mass was reallocated to the clubhead to improve its mass characteristics. Specifically, in this embodiment, the discretionary mass was reallocated to improve the CG position, prioritizing a lower CG position to provide a higher launch angle, less spin, and faster ball speed. The discretionary mass was reintroduced to the clubhead by adding mass to the mass pad on the sole. In other words, in the exemplary clubhead, a portion of the mass pad on the sole was thickened, creating a lower CG position. Thus, although both the control clubhead and the exemplary clubhead had the same total mass, the exemplary clubhead had a mass distribution more favorable for the purpose of CG placement.

[0161] Exemplary clubhead 1 showed a discretionary mass increase of 4.5 grams compared to the control clubhead, resulting in a decrease of 0.031 inches in CG height (CGy) and an increase of 0.011 inches in CG depth (CGz). The lower CG depth of the first exemplary clubhead can provide higher performance, such as a higher launch angle, less spin, and faster ball speed. The increased CG depth can help increase MOI and / or retention.

[0162] Exemplary clubhead 2 showed a discretionary mass increase of 5.5 grams compared to the control clubhead, resulting in a decrease of 0.036 inches in CG height (CGy) and an increase of 0.015 inches in CG depth (CGz). The lower CG depth of the second exemplary clubhead can provide higher performance, such as a higher launch angle, less spin, and faster ball speed. The increased CG depth can help increase MOI and / or retention.

[0163] This comparison demonstrates the advantages of providing a lightweight shaft support structure. The lightweight shaft support structure generates discretionary mass of 4.5 to 5.5 grams compared to the control club head, leading to an improvement in the CG position of the club head, which affects performance characteristics. As mentioned above, since the lightweight components of the lightweight shaft support structure described herein are not critical to withstanding stress loads, the creation of discretionary mass and the improvement in CG position are achieved without sacrificing the structural integrity of the club head.

[0164] (Example 3: Ball flight performance of a club head equipped with a lightweight shaft support structure) The ball flight performance of exemplary club heads was compared with that of a control club head. Ball speed, launch angle, and spin rate were measured and compared for each club head in field tests.

[0165] The exemplary club head was a fairway wood-type club head with a lightweight shaft support structure similar to that of shaft support structure 250. The first exemplary club head had a lightweight tube insert forming a hosel tube and a lightweight lower end cap forming the base of the hosel. The tube insert was inserted into the internal cavity from the lower opening. The end cap covered the lower opening and surrounded the tube insert within the internal cavity.

[0166] The control club head was a prior art fairway wood type club head equipped with a prior art shaft support structure similar to that of shaft support structure 150. The control club head had a hosel, hosel tube, and hosel base, each integrally formed with the club head body and made from the body material. The shaft support structure of the control club head did not have any lightweight components.

[0167] Table 2 below shows the results of the comparative study. [Table 2]

[0168] As is evident from Table 2, the exemplary clubhead exhibited an increased launch angle, a slight decrease in ball velocity, and substantially similar spin rates compared to the control clubhead. The increased launch angle is a result of the lower CG position achieved by discretionary mass created by including a lightweight shaft support structure (as is evident in Example 2). While the exemplary clubhead showed a slight decrease in raw ball velocity, the increased launch angle gives the exemplary clubhead the ability to deloft, restoring ball velocity to the exemplary clubhead and reducing spin rates. The ability to deloft the exemplary clubhead provided by the increased launch angle results in overall higher performance by producing a clubhead with equal or greater ball velocity and less spin compared to the control clubhead.

[0169] (Example 4: Durability of a club head equipped with a lightweight shaft support structure) The exemplary clubhead of Example 3 was further tested for durability. Three samples of the exemplary clubhead were subjected to an air cannon test, in which a golf ball was launched towards the clubhead face at a speed of 115 mph, simulating the high-speed impacts that occur between the clubhead and the ball during a golf swing. The first sample withstood 3164 impacts, the second sample withstood 3197 impacts, and the third sample withstood 2413 impacts. Thus, each of the three samples had durability similar to that of prior art golf clubheads. The durability of the three samples, which experienced a typical number of impacts, demonstrates that the structural integrity of the exemplary clubhead is sufficient for practical use. The results of the durability tests show that including a lightweight shaft support structure provides advantages in mass properties and performance (outlined in Examples 1 and 2) without sacrificing the durability of the clubhead.

[0170] (Clause) (Clause 1) A golf club head comprising a striking face and a body, wherein an internal cavity is defined by fixing the striking face and the body, the body comprising a crown, a sole opposite the crown, a heel, a toe opposite the heel, a skirt adjacent to the crown and the sole, and a shaft support structure, the shaft support structure comprising a hosel and a shaft sleeve, the hosel being formed of a first material having a first density, the hosel comprising a hosel wall defining at least a first portion of a hosel bore, an upper part of the hosel wall defining a hosel bore opening, and a hosel base opposite the hosel bore opening, the hosel base being provided on the inner surface of the sole near the heel, and the hosel defining a hosel bore axis concentric with the hosel bore, A golf club head comprising a shaft sleeve which is insertable into the hosel through the hosel bore opening and configured to connect a golf club shaft to the hosel, the hosel bore opening configured to receive the shaft sleeve, a lip formed at the bottom of the upper part of the hosel wall, the shaft receiving structure further comprising a tube insert which extends from the lip to the base of the hosel through the internal cavity, the tube insert which is separated from the hosel bore opening by the upper part of the hosel wall, the tube insert which is formed of a second material which has a second density which is less than the first density, the tube insert which defines the rest of the hosel bore, and the tube insert which seals the hosel bore from the internal cavity.

[0171] (Clause 2) The shaft support structure further comprises a hosel length measured parallel to the hosel bore axis from the hosel bore opening to the hosel base, The golf club head according to Clause 1, wherein the tube insert has a tube insert length measured from the upper end to the lower end of the tube insert, and the tube insert length is 70-90% of the hosel length.

[0172] (Clause 3) The golf club head described in Clause 2, wherein the length of the tube insert is between 1.00 inch and 1.50 inch.

[0173] (Clause 4) The golf club head according to Clause 1, wherein the lip is formed by a change in thickness between the upper part of the hosel wall and the remaining part of the hosel wall, and the upper part of the hosel wall has a greater thickness than the remaining part of the hosel wall.

[0174] (Clause 5) The golf club head according to Clause 1, wherein the second material is selected from the group consisting of thermosetting resins, thermoplastic resins, filler thermoplastics, fiber-reinforced composites, thermoplastic polyurethanes (TPU), or thermoplastic elastomers (TPE), and aluminum alloys.

[0175] (Item 6) The second density is 3 g / cm³ 3 A golf club head as described in Clause 1, which is less than [amount missing].

[0176] (Clause 7) The golf club head according to Clause 1, wherein the upper end of the tube insert is held by the lip, the shaft sleeve, and the hosel wall, and the lower end of the tube insert is held by the bottom lap joint, the hosel base, and the end cap.

[0177] (Clause 8) The golf club head according to Clause 1, wherein the hosel wall defines a top lap joint adjacent to the lip, the body defines a bottom lap joint extending from the hosel base to the internal cavity, and the tube insert is configured to be bonded and connected to the top lap joint and the bottom lap joint.

[0178] (Clause 9) A golf club head comprising a striking face and a body, wherein an internal cavity is defined by fixing the striking face and the body, the body comprising a crown, a sole opposite the crown, a heel, a toe opposite the heel, a skirt adjacent to the crown and the sole, and a shaft support structure, the shaft support structure comprising a hosel and a shaft sleeve, the hosel being formed of a first material having a first density, the hosel comprising a hosel wall defining at least a first portion of a hosel bore, a hosel bore opening located at the upper end of the hosel, and a hosel base opposite the hosel bore opening, the hosel base being formed on the inner surface of the sole near the heel, the hosel defining a hosel bore axis concentric with the hosel bore, and the shaft sleeve being insertable into the hosel through the hosel bore opening, and A golf club head comprising a shaft support structure configured to connect a golf club shaft to the hosel, wherein the hosel bore opening is configured to receive the shaft sleeve, the hosel further comprises a hosel wall upper adjacent to the hosel bore opening, the shaft support structure further comprises a tube insert extending from the hosel wall upper to the hosel base through the internal cavity, the tube insert being formed of a second material having a second density less than the first density, the tube insert defining the remainder of the hosel bore, the tube insert sealing the hosel bore from the internal cavity, and the shaft support structure comprising a tube insert offset distance measured parallel to the hosel bore axis and defined as the distance between the hosel bore opening and the upper end of the tube insert, wherein the tube insert offset distance is greater than 0.20 inches.

[0179] (Clause 10) The golf club head according to Clause 9, wherein the shaft support structure has a mass at least 3 grams less than the mass of a similar shaft support structure formed solely of the first material.

[0180] (Clause 11) The golf club head according to Clause 9, wherein the second material is selected from the group consisting of thermosetting resins, thermoplastic resins, filler thermoplastics, fiber-reinforced composites, thermoplastic polyurethanes (TPU), or thermoplastic elastomers (TPE), and aluminum alloys.

[0181] (Clause 12) The second density is 3 g / cm³ 3 A golf club head as described in Article 9, which is less than [amount missing].

[0182] (Clause 13) A golf club head comprising a striking face and a body, wherein an internal cavity is defined by the fixing of the striking face and the body, the body comprising a crown, a sole opposite the crown, a heel, a toe opposite the heel, a skirt adjacent to the crown and the sole, and a shaft support structure, the shaft support structure comprising a hosel and a shaft sleeve, the hosel being formed of a first material having a first density, the hosel comprising a hosel wall defining at least a first portion of a hosel bore and an upper part of the hosel wall defining a hosel bore opening, the shaft sleeve being insertable into the hosel through the hosel bore opening and configured to connect a golf club shaft to the hosel. A golf club head wherein the hosel bore opening is configured to receive the shaft sleeve, a lower opening is located on the sole opposite the hosel bore opening, and an end cap is configured to connect to the sole and close the lower opening, the shaft receiving structure further comprises a tube insert extending from the top of the hosel wall to the end cap through the internal cavity, the tube insert is formed of a second material having a second density less than the first density, the end cap is formed of a third material having a third density less than the first density, the tube insert defines the rest of the hosel bore, and the tube insert seals the hosel bore from the internal cavity.

[0183] (Clause 14) The golf club head according to Clause 13, wherein the end cap further comprises one or more notches configured to receive the lower end of the tube insert.

[0184] (Clause 15) The golf club head according to Clause 13, wherein the end cap further comprises an end cap body and a projection extending upward from the end cap body, the projection extending at least partially within the hosel bore.

[0185] (Clause 16) The golf club head according to Clause 13, wherein the end cap further comprises an opening extending through the end cap from the lower surface of the end cap to the upper surface of the end cap.

[0186] (Clause 17) The golf club head according to Clause 13, wherein the tube insert is configured to be inserted into the internal cavity through the lower opening.

[0187] (Clause 18) The golf club head according to Clause 13, wherein the second material is selected from the group consisting of thermosetting resins, thermoplastic resins, filler thermoplastics, fiber-reinforced composites, thermoplastic polyurethanes (TPU), or thermoplastic elastomers (TPE), and aluminum alloys.

[0188] (Clause 19) The second density is 3 g / cm³ 3 A golf club head less than the size specified in Article 13.

[0189] (Clause 20) The density of the third is 3 g / cm³ 3 A golf club head less than the size specified in Article 13.

[0190] The replacement of one or more claimed elements constitutes a reconstruction, not a repair. Furthermore, benefits, other advantages, and solutions to problems have been described with respect to specific embodiments. However, benefits, advantages, solutions to problems, and elements that may give rise to or make more prominent benefits, advantages, or solutions shall not be construed as material, essential, or essential features or elements of any or all of the claims unless such benefits, advantages, solutions, or elements are described in the claims.

[0191] Furthermore, the embodiments and limitations disclosed herein are not dedicated to the public under the doctrine of Dedication if (1) they are not expressly described in the claims, and (2) they are equivalent to, or potentially equivalent to, any express elements and / or limitations described in the claims, under the principle of equivalents.

Claims

1. It is a golf club head, The hitting face and, Equipped with a body, The internal cavity is defined by fixing the striking face and the body together. The body comprises a crown, a sole opposite the crown, a heel, a toe opposite the heel, a skirt adjacent to the crown and the sole, and a shaft support structure. The shaft support structure comprises a hosel and a shaft sleeve, The hosel is formed of a first material having a first density, The aforementioned hosel is A hosel wall defining at least a first portion of the hosel bore, The upper part of the hosel wall that defines the hosel bore opening, The hosel base on the opposite side of the hosel bore opening comprises, The hosel base is provided on the inner surface of the sole, near the heel. The hosel defines a hosel bore axis that is concentric with the hosel bore, The shaft sleeve is insertable into the hosel through the hosel bore opening and is configured to connect the golf club shaft to the hosel. The hosel bore opening is configured to receive the shaft sleeve, The lip is formed in the inner bottom of the upper part of the hosel wall, The lip is formed by a change in thickness between the upper part of the hosel wall and the rest of the hosel wall. The upper part of the hosel wall has a greater thickness than the remaining part of the hosel wall. The shaft support structure further includes a tube insert that extends from the lip to the hosel base through the internal cavity, The tube insert is separated from the hosel bore opening by the upper part of the hosel wall and is in contact with the lip. The tube insert is formed of a second material having a second density lower than the first density. The tube insert defines the remaining portion of the hosel bore, The tube insert seals the hosel bore from the internal cavity, The shaft sleeve is located inside the tube insert. Golf club head.

2. The shaft support structure further comprises a hosel length measured parallel to the hosel bore axis from the hosel bore opening to the hosel base, The tube insert has a tube insert length measured from the upper end to the lower end of the tube insert, The golf club head according to claim 1, wherein the length of the tube insert is 70 to 90% of the length of the hosel.

3. The golf club head according to claim 2, wherein the length of the tube insert is between 1.00 inch and 1.50 inch.

4. The golf club head according to claim 1, wherein the second material is selected from the group consisting of thermosetting resin, thermoplastic resin, filler thermoplastic material, fiber-reinforced composite material, thermoplastic polyurethane (TPU), or thermoplastic elastomer (TPE), and aluminum alloy.

5. The second density is 3 g / cm³ ３ A golf club head according to claim 1, which is less than [amount missing].

6. The upper end of the tube insert is held by the lip, the shaft sleeve, and the hosel wall. The golf club head according to claim 1, wherein the lower end of the tube insert is held by a bottom lap joint, the hosel base, and an end cap.

7. The hosel wall defines a top lap joint adjacent to the lip, The body defines a bottom lap joint extending from the hosel base to the internal cavity, The golf club head according to claim 1, wherein the tube insert is configured to be bonded and connected to the top lap joint and the bottom lap joint.

8. It is a golf club head, The hitting face and, Equipped with a body, The internal cavity is defined by fixing the striking face and the body together. The body comprises a crown, a sole opposite the crown, a heel, a toe opposite the heel, a skirt adjacent to the crown and the sole, and a shaft support structure. The shaft support structure comprises a hosel and a shaft sleeve, The hosel is formed of a first material having a first density, The aforementioned hosel is A hosel wall defining at least a first portion of the hosel bore, The hosel bore opening located at the upper end of the hosel, The hosel base on the opposite side of the hosel bore opening comprises, The hosel base is formed on the inner surface of the sole, near the heel. The hosel defines a hosel bore axis that is concentric with the hosel bore, The shaft sleeve is insertable into the hosel through the hosel bore opening and is configured to connect the golf club shaft to the hosel. The hosel bore opening is configured to receive the shaft sleeve, The hosel further comprises an upper part of the hosel wall adjacent to the hosel bore opening, The lip is formed in the inner bottom of the upper part of the hosel wall, The lip is formed by a change in thickness between the upper part of the hosel wall and the rest of the hosel wall. The upper part of the hosel wall has a greater thickness than the remaining part of the hosel wall. The shaft support structure further includes a tube insert that extends from the upper part of the hosel wall to the base of the hosel, passing through the internal cavity. The tube insert is formed of a second material having a second density lower than the first density. The tube insert defines the remaining portion of the hosel bore, The tube insert seals the hosel bore from the internal cavity, The shaft sleeve is positioned inside the tube insert, The shaft support structure comprises a tube insert offset distance, which is measured parallel to the hosel bore axis and defined as the distance between the hosel bore opening and the upper end of the tube insert. The tube insert offset distance is greater than 0.20 inches. Golf club head.

9. The golf club head according to claim 8, wherein the shaft support structure has a mass at least 3 grams less than the mass of a similar shaft support structure formed solely of the first material.

10. The golf club head according to claim 8, wherein the second material is selected from the group consisting of thermosetting resin, thermoplastic resin, filler thermoplastic material, fiber-reinforced composite material, thermoplastic polyurethane (TPU), or thermoplastic elastomer (TPE), and aluminum alloy.

11. The second density is 3 g / cm³ ３ A golf club head according to claim 8, which is less than [amount missing].

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