Golf club head including a flexible sole

Abstract

To cause a club head to deform greatly during collision.SOLUTION: In one embodiment, a golf club head 400 includes a body having a crown opposite a sole 412, a toe opposite a heel, a back end 408 opposite a front end 406, and a hosel. The golf club head also includes a sole curvature profile comprising a radius of curvature that varies as the sole curvature profile extends between the front end and the back end. The radius of curvature is configured to increase the flexure of the entire golf club head, thereby increasing the internal energy of the golf club head.SELECTED DRAWING: Figure 10

Description

Technical Field

[0001] (Cross - Reference to Related Applications) This application claims the benefit of priority of U.S. Provisional Patent Application No. 62 / 861,247, filed Jun. 13, 2019; U.S. Provisional Patent Application No. 62 / 856,637, filed Jun. 3, 2019; and U.S. Provisional Patent Application No. 62 / 690,858, filed Jun. 27, 2018, the contents of which are hereby incorporated by reference in their entirety.

[0002] The present disclosure generally relates to golf clubs, and more particularly to golf club heads including a flexible sole.

Background Art

[0003] Metalwood golf club heads typically include a high - strength metal face plate attached to a hollow metal club body. When a metalwood club head strikes a golf ball, the distance the ball travels is primarily a function of the kinetic energy transferred from the club head to the ball. During the collision, some of the energy is lost as a result of the collision. One measure of the energy transfer from the club head to the golf ball is the coefficient of restitution ( "COR"). In contrast to the relatively small deformation of the club head, most of the energy is lost as a result of the large stresses and deformations of the golf ball. Therefore, in order to reduce the amount of energy lost during the collision and thus increase the energy transfer efficiency, the stresses and deformation rates applied to the golf ball during the collision must be reduced.

[0004] One way to achieve this is to allow for greater deformation of the club head during impact. For example, this can be achieved by increasing the deflection of the face plate. A typical way to increase the deflection of the face plate includes thinning a uniform face plate, varying the thickness of the face plate, providing ribbed stiffeners on the face plate, using a lighter material such as titanium, and providing a forged, punched, or machined metal face plate instead of a cast face plate.

[0005] Another way to increase the deformation of the club head during impact is to increase the deformation of the club head body. This can be achieved by changing the shape of the club head body to have a radius of curvature between a front region and a rear region. Some prior art club heads achieve this by providing a sole region with a greater outward camber between the front and rear of the club head. The greater outward camber disperses stress over a wider area in the sole region and allows the thickness of the sole region to be reduced to promote greater deformation. However, these prior art sole regions "curve outwardly in an arcuate shape" towards the ground and away from the centerline of the club head. As a result, the strike face will be positioned higher above the ground at the address position, making it more difficult to achieve a desirable contact during impact. There is a need in the art for a golf club head that does not curve outwardly in an arcuate shape towards the ground at the address position, has a significant camber in the sole, or has other structures that result in an optimal deformation of the golf club.

Brief Description of the Drawings

[0006]

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Mode for Carrying Out the Invention

[0007] For the sake of simplicity and clarity of the figures, the drawings show the general aspects of the structure, and descriptions and details of known features and techniques may be omitted to avoid unnecessarily obscuring the golf club and the method of manufacturing the golf club. Furthermore, the elements in the drawings are not necessarily drawn to a constant scale. For example, the dimensions of some elements in the figures may be exaggerated compared to other elements to help deepen the understanding of the embodiments of the golf club and the method of manufacturing the golf club. The same reference numerals in different drawings represent the same elements.

[0008] A metalwood golf club head including a body with a reverse camber sole is described herein. In particular, the sole of the club head includes a recessed area that includes an area of reverse concavity compared to the recesses of the remaining area of the sole. The reverse camber sole follows a more sharply curved profile between the leading edge and the trailing edge of the club head compared to prior art metalwood club heads. This makes it more likely to produce greater flexing in the sole of the body when the club head strikes a golf ball. The relatively greater flexing of the club body can result in a higher internal energy of the club head compared to prior art metalwood golf clubs. The higher internal energy of the club head results in a golf shot that travels further. Additionally, the relatively greater flexing of the sole during impact can result in a reduction in the ball spin rate imparted to the golf ball upon impact with the club head.

[0009] In some embodiments, the club head described herein may further include one or more internal beams mounted to the sole at a first end and at a second end, and extending through an internal cavity of the golf club head between the first end and the second end. The first end of each beam is mounted to the sole at a location proximate to the leading edge of the golf club head, and the second end of each beam is mounted to the sole in or near the recessed area. The internal beams reinforce the sole to prevent failure while making it more likely to produce further flexing in the sole during impact with a golf ball.

[0010] When terms such as "first", "second", "third", "fourth", etc. are present in this description and in the claims, they are used to distinguish similar elements and do not necessarily describe a particular sequential or chronological order. It should be understood that the terms used as described above are interchangeable with each other in appropriate circumstances so that embodiments of the golf clubs and manufacturing methods described herein can be implemented in a different order than, for example, those shown herein or described otherwise. Further, expressions such as "comprising", "including", and "having", and synonyms thereof, are intended to include non-exclusive inclusion, and thus a process, method, article, or apparatus that includes a listing of elements is not necessarily limited to those elements and may include other elements not explicitly listed or inherently provided in such process, method, article, or apparatus.

[0011] When terms such as "left", "right", "front", "rear", "upper", "bottom", "side", "lower", "upper", etc. are present in this description and in the claims, they are used for illustrative purposes and do not necessarily describe a permanent relative position. It is understood that the terms used as described above are interchangeable with each other in appropriate circumstances, and thus embodiments of the golf clubs and manufacturing methods described herein can be implemented in other orientations different from, for example, those shown herein or described otherwise. The term "coupled" as used herein is defined as being directly or indirectly connected by physical means, mechanical means, or other means.

[0012] Before any embodiment of the present disclosure is described in detail, it should be understood that the present disclosure is not limited to the detailed structures and arrangements of components described in the following description or shown in the following drawings in its application. The present disclosure can be other embodiments and can be implemented or executed in various ways.

[0013] Figures 1-4 illustrate one embodiment of a golf club head 100 having a flexible sole 112. The sole 112 is designed to warp inwardly (away from the ground surface), thereby increasing the flexibility of the golf club head 100 upon impact with a golf ball. This increase results in a greater internal energy being generated by the golf club head 100. This increase in internal energy increases the ball speed of the golf ball struck by the golf club head 100. The faster ball speed subsequently directly means a golf shot that travels farther. The inwardly warped sole results in a distance that is 5 to 10 yards longer than a golf club head that does not have an inwardly warped sole. The golf club head 100 may further include one or more stiffening beams 290 that suppress and control the flexibility of the golf club head 100.

[0014] I. Inwardly Warped Golf Club Head Figures 1-4 illustrate a golf club head 100 having a body 102 and a striking face 104. The body 102 of the club head 100 includes a front end portion 106, a rear end portion 108 opposite the front end portion 106, a crown 110, a sole 112 opposite the crown 110, a heel 114, and a toe 116 opposite the heel 114. The sole 112 of the golf club head 100 includes a ground surface 113, and when the golf club head 100 is in an address position for striking a golf ball, the ground surface 113 contacts the sole 112.

[0015] The club head 100 is a hollow body club head. The golf club head 100 includes a body 102 and a striking face 104. The body 102 and the striking face 104 define an internal cavity 118 (FIG. 4) of the golf club head 100. In the illustrated embodiment, the body 102 further defines a crown 110, a sole 112, a heel 114, a toe 116, a rear end portion 108, and an outer edge portion 120 (FIG. 3) of the front end portion 106 of the club head 100. These features may further define the hollow body. The outer edge portion 120 of the body 102 further defines an opening 122 at the front end portion 106 of the club head 100, and the striking face 104 is coupled to the outer edge portion 120 so as to close the opening 122, thereby forming the club head 100. In other embodiments (not shown), the striking face 104 may extend across the entire front end portion 106 of the club head and may include a return portion that extends across at least one of the crown 110, the sole 112, the heel 114, and the toe 116. In these embodiments, the return portion of the striking face 104 is coupled to the body 102 so as to form the club head 100.

[0016] As shown in FIG. 3, the club head 100 further includes a hosel structure 124 and a hosel shaft 126 that extends centrally along a hole of the hosel structure 124. The hosel structure 124 can be coupled to an end of a golf shaft (not shown). The golf shaft can be fixed to the hosel structure 124 at a plurality of angles with respect to the hosel shaft 126. However, there may be other examples where the shaft can be fixedly and non-adjustably attached to the hosel structure 124.

[0017] The club head 100 defines a depth 140, a length 142, and a height 144. Referring to FIG. 4, the depth 140 of the club head 100 can be measured as the most distant extent of the club head 100 from the front end portion 106 to the rear end portion 108 in a direction parallel to the Z-axis 1016.

[0018] The length 142 of the club head 100 can be measured as the farthest range of the club head 100 from the heel 114 to the toe 116 in a direction parallel to the X-axis 1012 when viewed from the front view (FIG. 3). In many embodiments, the length 142 of the club head 100 can be measured in accordance with a golf governing organization, such as the United States Golf Association (USGA). For example, the length 142 of the club head 100 can be specified in accordance with the USGA procedures for measuring the club head size of a wood club (USGA-TPX3003, Rev. 2.1, April 9, 2019).

[0019] The height 144 of the club head 100 can be measured as the farthest range of the club head 100 from the crown 110 to the sole 112 in a direction parallel to the Y-axis 1014 when viewed from the front view (FIG. 3). In many embodiments, the height 144 of the club head 100 can be measured in accordance with a golf governing organization, such as the USGA. For example, the height 144 of the club head 100 can be specified in accordance with the USGA procedures for measuring the club head size of a wood club.

[0020] In many embodiments, the volume (V) of the club head 100 is greater than about 150 cc, greater than about 160 cc, greater than about 170 cc, greater than about 170 cc, greater than about 180 cc, greater than about 190 cc, or greater than about 195 cc. In some embodiments, the volume (V) of the club head can be about 150 cc to 198 cc, 160 cc to 198 cc, 170 cc to 198 cc, about 180 cc to 198 cc, or about 190 cc to 199 cc.

[0021] Furthermore, in many embodiments, the volume of the club head 100 is greater than about 400 cc, greater than about 425 cc, greater than about 450 cc, greater than about 475 cc, greater than about 500 cc, greater than about 525 cc, greater than about 550 cc, greater than about 575 cc, greater than about 600 cc, greater than about 625 cc, greater than about 650 cc, greater than about 675 cc, or greater than about 700 cc. In some embodiments, the volume of the club head 100 can be from about 400 cc to 600 cc, 425 cc to 500 cc, about 500 cc to 600 cc, about 500 cc to 650 cc, about 550 cc to 700 cc, about 600 cc to 650 cc, about 600 cc to 700 cc, or about 600 cc to 800 cc.

[0022] Continuing to refer to FIG. 3, the strike face 104 of the club head 100 defines a center point or geometric center 128. In some embodiments, the geometric center 128 can be located at the geometric center point of the strike face outer edge 130 and at the midpoint of the face height 132. In the same or other examples, the geometric center 128 can be further centered with respect to a designed collision zone 134 defined by the region of the groove 136 in the strike face 104. As another approach, the geometric center 128 of the strike face 104 can conform to the definition of a golf governing organization, such as the United States Golf Association (USGA). For example, the geometric center 128 of the strike face 104 can be specified in accordance with section 2.1 of the USGA procedure for measuring the flexibility of a golf club head (USGA-TPX3004, Rev. 2.0, April 9, 2019).

[0023] Referring to FIGS. 3 and 4, the club head 100 further defines a loft plane 1010 that is in contact with the geometric center 128 of the strike face 104. The face height 132 can be measured parallel to the loft plane 1010 between the upper end of the strike face outer edge 130 near the crown 110 and the lower end of the strike face outer edge 130 near the sole 112.

[0024] The geometric center 128 of the striking face 104 further defines a coordinate system of the golf club head 100 having an origin located at the geometric center 128 of the striking face 104. The coordinate system further comprises an X-axis 1012, a Y-axis 1014, and a Z-axis 1016. The X-axis 1012 extends through the geometric center 128 of the striking face 104 in a direction from the heel 114 to the toe 116 of the club head 100. The Y-axis 1014 extends through the geometric center 128 of the striking face 104 in a direction from the crown 110 to the sole 112 of the club head 100 and is orthogonal to the X-axis 1012. The Z-axis 1016 extends through the geometric center 128 of the striking face 104 in a direction from the front end 106 to the rear end 108 of the club head 100 and is orthogonal to both the X-axis 1012 and the Y-axis 1014.

[0025] The coordinate system defines an XY plane 1018 extending through the X-axis 1012 and the Y-axis 1014, an XZ plane 1020 extending through the X-axis 1012 and the Z-axis 1016, and a YZ plane 1022 extending through the Y-axis 1014 and the Z-axis 1016. The XY plane 1018, the XZ plane 1020, and the YZ plane 1022 are all orthogonal to each other and intersect at the origin of the coordinate system located at the geometric center 128 of the striking face 104. The XY plane 1018 extends parallel to the hosel axis 126 and is positioned at an angle corresponding to the loft angle 138 of the club head 100 from the loft plane 1010. Further, the X-axis 1012 is positioned at an angle of approximately 60 degrees with respect to the hosel axis 126 when viewed from a direction orthogonal to the XY plane 1018 (i.e., as seen in FIG. 4). In other embodiments, the X-axis 1012 may be positioned at an angle of 45 degrees to 70 degrees with respect to the hosel axis 126 when viewed from a direction orthogonal to the XY plane 1018.

[0026] In these or other embodiments, when the striking face 104 is viewed from a direction orthogonal to the XY plane 1018, the club head 100 can be viewed from a front view (such as that shown in FIG. 3, for example). Further, in these or other embodiments, when the heel 114 is viewed from a direction orthogonal to the YZ plane 1022, the club head 100 can be viewed from a side view or a side cross-sectional view (such as that shown in FIG. 4, for example).

[0027] As shown in FIGS. 3 and 4, the club head 100 further includes a head center of gravity (CG) 146 and a head depth plane 1024. The head depth plane 1024 is orthogonal to the loft plane 1010 in the direction from the heel 114 to the toe 116 of the club head 100 and extends through the geometric center 128 of the striking face 104. In many embodiments, the head CG 146 is located at a head CG depth from the XY plane 1018 and is measured in a direction orthogonal to the XY plane 1018. In some embodiments, the head CG 146 can be located at a head CG depth 148 from the loft plane 1010 and measured in a direction orthogonal to the loft plane 1010. The head CG 146 is further located at a head CG height 150 from the head depth plane 1024 and is measured in a direction orthogonal to the head depth plane 1024. Further, the head CG height 150 is measured as an offset distance from the head depth plane 1024 in a direction orthogonal to the head depth plane 1024 that is toward the crown 110 or toward the sole 112. In many embodiments, when the head CG 146 is located above the head depth plane 1024 (i.e., between the head depth plane 1024 and the crown 110), the head CG height 150 is a positive value, and when the head CG 146 is located below the head depth plane 1024 (i.e., between the head depth plane 1024 and the sole 112), the head CG height 150 is a negative value. In some embodiments, the absolute value of the head CG height 150 can account for the head CG 146 located above or below the head depth plane 1024 (i.e., between the head depth plane 1024 and the crown 110 or between the head depth plane 1024 and the sole 112). In many embodiments, the head CG 146 is strategically positioned toward the sole 112 and the rear end 108 of the club head 100.

[0028] The head CG146 defines the origin of a coordinate system having an X'-axis 1026, a Y'-axis 1028, and a Z'-axis 1030. The Y'-axis 1028 is parallel to the hosel axis 126 when viewed in a side view and, when viewed in a front view (i.e., as seen in FIG. 3), extends through the head CG146 from the crown 110 to the sole 112 at an angle of 30 degrees with respect to the hosel axis 126. The X'-axis 1026 extends through the head CG146 from the heel 114 to the toe 116, is orthogonal to the Y'-axis 1028 when viewed in a front view, and extends parallel to the XY plane 1018. The Z'-axis 1030 extends through the head CG146 from the front end 106 to the rear end 108 and extends orthogonal to the X'-axis 1026 and the Y'-axis 1028. In many embodiments, the X'-axis 1026 extends through the head CG146 from the heel 114 to the toe 116 parallel to the X-axis 1012. The Y'-axis 1028 extends through the head CG146 from the crown 110 to the sole 112 parallel to the Y-axis 1014. The Z'-axis 1030 extends through the head CG146 from the front end 106 to the rear end 108 parallel to the Z-axis 1016.

[0029] While the above example may be described in relation to a wood-type golf club 100, the devices, methods, and products described herein may be applicable to various types of golf clubs including drivers, fairway woods, hybrids, crossovers, or any hollow body-type golf club.

[0030] The club head 100 further comprises a loft angle (not shown) measured as the angle between the loft plane 1010 and the ground plane 113. In many embodiments, the loft angle ranges between about 7 degrees and 40 degrees. In some embodiments, the loft angle of the club head 100 is 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.

[0031] In many embodiments, the loft angle of the club head 100 is 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. Further, in many embodiments, the loft angle of the club head 100 is greater than about 12 degrees, greater than about 13 degrees, greater than about 14 degrees, greater than about 15 degrees, greater than about 16 degrees, greater than about 17 degrees, greater than about 18 degrees, greater than about 19 degrees, or greater than about 20 degrees. For example, in some embodiments, the loft angle of the club head 100 can be between 12 degrees and 35 degrees, between 15 degrees and 35 degrees, between 20 degrees and 35 degrees, or between 12 degrees and 30 degrees.

[0032] In many embodiments, the loft angle of the club head 100 is 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. Further, in many embodiments, the loft angle of the club head 100 is 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.

[0033] The striking face 104 of the club head 100 is formed from a first material. In many embodiments, the first material can be a metal alloy, such as a titanium alloy (e.g., Ti 7-4, Ti 6-4, T-9S, Ti SSAT2041, Ti SP700, Ti 15-0-3, Ti 15-5-3, Ti 3-8-6-4-4, Ti 10-2-3, Ti 15-3-3-3, Ti-6-6-2, Ti-185, etc., or any combination thereof), a steel alloy (e.g., C300 steel, C350 steel, 455 steel, 431 steel, 475 steel, 565 steel, 17-4 stainless steel, maraging steel, Ni-Co-Cr steel alloy, etc.), an aluminum alloy, or any other metal or metal alloy. In other embodiments, the first material can be another material, such as a composite material, plastic, thermoplastic composite material, or any other suitable material or combination of materials.

[0034] The body 102 of the club head 100 is formed from a second material. In many embodiments, the first material can be a metal alloy, such as a titanium alloy (e.g., Ti 7-4, Ti 6-4, T-9S, Ti SSAT2041, Ti SP700, Ti 15-0-3, Ti 15-5-3, Ti 3-8-6-4-4, Ti 10-2-3, Ti 15-3-3-3, Ti-6-6-2, Ti-185, etc., or any combination thereof), a steel alloy (e.g., C300 steel, C350 steel, 455 steel, 431 steel, 475 steel, 565 steel, 17-4 stainless steel, maraging steel, Ni-Co-Cr steel alloy, etc.), an aluminum alloy, or any other metal or metal alloy. In other embodiments, the first material can be another material, such as a composite material, plastic, or any other suitable material or combination of materials. In the illustrated embodiment, the second material is different from the first material. In other embodiments, the first material and the second material can be the same.

[0035] II. Reverse sole Referring to FIG. 2, the sole 112 of the golf club head 100 further includes a recess or indented region 152 where the sole 112 curves inward in a direction toward the internal cavity 118 (FIG. 4). In relation to the XZ plane 1020 (FIG. 4), the indented region 152 includes a reverse camber region 154 that is convex with respect to the XZ plane 1020. A typical prior art metalwood includes a sole profile that is only concave with respect to an equivalent XZ plane. Thus, a typical prior art metalwood includes a sole profile having a relatively large radius of curvature (i.e., a radius of curvature of about 22 inches to 25 inches) between the front end and the rear end. In contrast, the indented region 152 of the golf club head 100 allows the sole 112 to follow a profile that curves much more sharply between the front end 106 and the rear end 108. For example, in some embodiments of the club head 100, when viewed from a side cross-sectional view taken along the YZ plane 1022 (as seen, for example, in FIG. 4), no portion of the sole 112 cut by the YZ plane 1022 includes a radius of curvature greater than 10 inches between the front end 106 and the rear end 108.

[0036] Furthermore, in the illustrated embodiment of the club head 100, when viewed from a side cross-sectional view taken along the YZ plane 1022, no portion of the sole 112 includes a radius of curvature greater than 6 inches. By implementing the indented region 152 in the sole 112, a relatively small radius of curvature of the sole 112 is achieved between the front end 106 and the rear end 108, and the club head body 102 undergoes greater deformation at the sole 112 during a collision with a golf ball. This results in an increase in the flex of the golf club head 100 and more efficient energy transfer from the club head 100 to the ball during the collision. The curvature of the sole 112 is described in more detail below.

[0037] Referring to FIG. 4, the club head 100 includes a face - sole transition boundary 156 (FIG. 2) where the front end 106 transitions to the sole 112. The face - sole transition boundary 156 extends from near the heel 114 to near the toe 116 between the front end 106 and the sole 112. The face - sole transition profile 158 is defined at the location where the face - sole transition boundary 156 is cut by the YZ plane 1022. That is, the face - sole transition profile 158 is the linear portion of the face - sole transition boundary 156 cut by the YZ plane 1022 as it appears when viewed from a side cross - sectional view taken along the YZ plane 1022 (as seen, for example, in FIG. 4).

[0038] The face - sole transition profile 158 follows the face - sole transition radius of curvature R1. The face - sole transition profile 158 extends from a strike - face transition point 160 where the outer shape of the strike face 104 deviates from the roll radius of the strike face 104 to a sole transition point 162. At the sole transition point 162, the curvature of the sole 112 deviates from the face - sole transition radius of curvature R1. The sole transition point 162 is defined by the intersection of the strike face 104 and the sole 112. In some embodiments, the face - sole transition radius of curvature R1 has a constant radius of curvature from the strike - face transition point 160 to the sole transition point 162.

[0039] In some embodiments, the face - sole transition radius of curvature R1 can range from about 0.10 inches to 0.50 inches. For example, the face - sole transition radius of curvature R1 can be less than about 0.5 inches, less than about 0.475 inches, less than about 0.45 inches, less than about 0.425 inches, or less than about 0.40 inches. In a further example, the face - sole transition radius of curvature R1 can be about 0.10 inches, 0.15 inches, 0.20 inches, 0.25 inches, 0.30 inches, 0.35 inches, 0.40 inches, 0.45 inches, or 0.50 inches.

[0040] Continuing with reference to FIG. 4, the sole 112 defines an outer sole surface 164 (FIG. 2) that extends from the front end portion 106 to the rear end portion 108 and from the heel 114 to the toe 116. The sole curvature profile 166 of the club head 100 is defined as a linear extent of the sole surface 164 that is cut by the YZ plane 1022 and extends from the sole transition point 162 to the rear end portion 108. The sole curvature profile 166 includes a first concave section 168, a convex section 170, and a second concave section 172. The first concave section 168 extends from the sole transition point 162 to the first inflection point 174 and is concave with respect to the XZ plane 1020 (convex with respect to the ground plane 113). The first inflection point 174 is along the sole curvature profile 166 when tracing the sole curvature profile 166 from the front end portion 106 toward the rear end portion 108 and is defined as the first point where the sole curvature profile 166 reverses its concave portion with respect to the XZ plane 1020.

[0041] The convex section 170 of the sole curvature profile 166 extends from the first inflection point 174 to the second inflection point 176 and is convex with respect to the XZ plane 1020 (concave with respect to the ground plane 113). The second inflection point 176 is along the sole curvature profile 166 when tracing the sole curvature profile 166 from the front end portion 106 toward the rear end portion 108 and is defined as the second point where the sole curvature profile 166 reverses its concave portion with respect to the XZ plane 1020. The second concave section 172 of the sole curvature profile 166 extends from the second inflection point 176 to the rear end portion 108 and is concave with respect to the XZ plane 1020 (convex with respect to the ground plane 113).

[0042] Continuing to refer to FIG. 4, the club head 100 further includes a first inflection point depth 178 measured along a direction orthogonal to the loft plane 1010 between the loft plane 1010 and the first inflection point 174. In many embodiments, the first inflection point depth 178 of the club head 100 is greater than 0.50 inches. In the illustrated embodiment, the first inflection point depth 178 is approximately 1.50 inches. In other embodiments, the first inflection point depth 178 of the club head 100 is greater than 0.75 inches, greater than 1.00 inches, greater than 1.10 inches, greater than 1.20 inches, greater than 1.30 inches, greater than 1.40 inches, greater than 1.50 inches, greater than 1.60 inches, greater than 1.70 inches, greater than 1.80 inches, greater than 1.90 inches, greater than 2.00 inches, greater than 2.25 inches, or greater than 2.50 inches. For example, in some embodiments, the first inflection point depth 178 of the club head 100 can be between 0.50 inches and 2.50 inches, between 1.00 inches and 2.00 inches, between 1.25 inches and 1.75 inches, between 1.35 inches and 1.65 inches, or between 1.45 inches and 1.55 inches. In some embodiments, the first inflection point depth 178 of the club head 100 can be 0.50 inches, 0.75 inches, 1.0 inches, 1.25 inches, 1.50 inches, 1.75 inches, 2.00 inches, 2.25 inches, or 2.50 inches.

[0043] The first inflection point depth ratio of the club head 100 is defined as the ratio of the first inflection point depth 178 to the depth 140 of the club head 100. In many embodiments, the first inflection point depth ratio is greater than 0.25. In other embodiments, the first inflection point depth ratio is greater than 0.30, greater than 0.31, greater than 0.32, greater than 0.33, greater than 0.34, greater than 0.35, greater than 0.36, greater than 0.37, greater than 0.38, greater than 0.39, greater than 0.40, or greater than 0.45. For example, in some embodiments, the first inflection point depth ratio of the club head 100 can be between 0.25 and 0.45, between 0.30 and 0.45, between 0.25 and 0.40, between 0.30 and 0.40, between 0.32 and 0.38, or between 0.34 and 0.36. In some embodiments, the first inflection point depth ratio of the club head 100 can be 0.25, 0.26, 0.27, 0.28, 0.29, 0.30, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37, 0.38, 0.39, 0.40, 0.41, 0.42, 0.43, 0.44, or 0.45.

[0044] Continuing to refer to FIG. 4, the sole 112 of the club head 100 further defines a back portion 180. The back portion 180 is located along the cross-section of the sole curvature profile 166 that extends through the recessed region 152 (FIG. 2). In particular, the back portion 180 is defined as the point within the recessed region 152 and closest to the sole curvature profile 166 in the XZ plane 1020. In most embodiments, the back portion 180 is located in the convex section 170. In other words, the back portion 180 represents the lowest point of the recessed region 152 when the recessed region 152 extends toward the internal cavity 118.

[0045] The club head 100 further includes a back height (not shown), which is measured vertically from the ground contact surface 113 to the back 180. In many embodiments, the back height of the club head 100 ranges between 0.01 inch and 0.30 inch. In other embodiments, the back height of the club head 100 can range between 0.01 inch and 0.05 inch, 0.05 inch and 0.10 inch, 0.10 inch and 0.15 inch, 0.15 inch and 0.20 inch, 0.20 inch and 0.25 inch, or 0.25 inch and 0.30 inch. In other embodiments, the back height can be 0.01 inch, 0.02 inch, 0.03 inch, 0.04 inch, 0.05 inch, 0.06 inch, 0.07 inch, 0.08 inch, 0.09 inch, 0.10 inch, 0.11 inch, 0.12 inch, 0.13 inch, 0.14 inch, 0.15 inch, 0.16 inch, 0.17 inch, 0.18 inch, 0.19 inch, 0.20 inch, 0.21 inch, 0.22 inch, 0.23 inch, 0.24 inch, 0.25 inch, 0.26 inch, 0.27 inch, 0.28 inch, 0.29 inch, or 0.30 inch.

[0046] The club head 100 further includes a back depth 182 measured along a direction orthogonal to the loft plane 1010 between the loft plane 1010 and the back 180. In many embodiments, the back depth 182 of the club head 100 is greater than 1.5 inches. In other embodiments, the back depth 182 of the club head 100 is greater than 1.6 inches, greater than 1.7 inches, greater than 1.8 inches, greater than 1.9 inches, greater than 2.0 inches, greater than 2.1 inches, greater than 2.2 inches, greater than 2.3 inches, greater than 2.4 inches, or greater than 2.5 inches. For example, in some embodiments, the back depth 182 of the club head 100 can be between 1.5 inches and 3.0 inches, between 1.5 inches and 2.5 inches, between 2.0 inches and 3.0 inches, between 2.0 inches and 2.5 inches, or between 2.5 inches and 3.0 inches.

[0047] The back depth ratio of the club head 100 is defined as the ratio of the back depth 182 to the depth 140 of the club head 100. In many embodiments, the back depth ratio is greater than 0.35. In other embodiments, the back depth ratio is greater than 0.40, greater than 0.45, greater than 0.46, greater than 0.47, greater than 0.48, greater than 0.49, greater than 0.50, greater than 0.51, greater than 0.52, greater than 0.53, greater than 0.54, greater than 0.55, or greater than 0.60. For example, in some embodiments, the back depth ratio B of the club head 100 can be between 0.40 and 0.60, between 0.45 and 0.60, between 0.40 and 0.55, between 0.45 and 0.55, between 0.47 and 0.53, or between 0.49 and 0.51.

[0048] The sole curvature profile 166 of the club head 100 can be further described in terms of the radius of curvature along each of the various sections of the sole curvature profile 166 between the front end portion 106 and the rear end portion 108. Referring to FIG. 4, the first concave section 168 of the sole curvature profile 166 is divided into a first curved section 184 having a first section radius of curvature R2 and a second curved section 186 having a second section radius of curvature R3. The first curved section 184 extends from the sole transition point 162 to the first concave section transition point 188. The first concave section transition point 188 is defined as the point along the sole curvature profile 166 where the first section radius of curvature R2 transitions to the second section radius of curvature R3. The second curved section 186 extends from the first concave section transition point 188 to the first inflection point 174 that divides the second curved section 186 from the convex section 170. The convex section 170 of the sole curvature profile 166 includes a convex section radius of curvature R4. Finally, the second concave section 172 includes a second concave section radius of curvature R5.

[0049] In some embodiments, the radius of curvature R2 of the first section can range from about 1.00 inch to 3.50 inches. In the illustrated embodiment, the radius of curvature R2 of the first section is about 1.75 inches. In other embodiments, the radius of curvature R2 of the first section can be less than 3.00 inches, less than 2.50 inches, less than 2.25 inches, less than 2.00 inches, or less than 1.75 inches. For example, the radius of curvature R2 of the first section can be about 1.00 inch, 1.25 inches, 1.5 inches, 1.75 inches, 2.00 inches, 2.25 inches, or 2.50 inches.

[0050] In some embodiments, the radius of curvature R3 of the second section can range from about 1.0 inch to 10.0 inches. In one embodiment, the radius of curvature R3 of the second section is about 6.0 inches. In other embodiments, the radius of curvature R3 of the second section can be less than 9.0 inches, less than 8.0 inches, less than 7.0 inches, less than 6.0 inches, less than 5.0 inches, less than 4.0 inches, less than 3.0 inches, or less than 2.0 inches. For example, the radius of curvature R3 of the second section can be about 3.0 inches, 4.0 inches, 5.0 inches, 6.0 inches, 7.0 inches, 8.0 inches, or 9.0 inches.

[0051] The back height ratio of the club head 100 is defined as the ratio of the back height to the radius of curvature R3 of the first concave section 168. The back height is inversely proportional to the radius of curvature R3. As the magnitude of the radius of curvature R3 decreases, the back height increases. As the magnitude of the radius of curvature R3 increases, the back height decreases. In many embodiments, the back height ratio is 0.33 or less. In other embodiments, the back height ratio is less than 0.30, less than 0.25, less than 0.20, less than 0.15, less than 0.10, or less than 0.05. In other embodiments, the back height ratio can range between 0.001 - 0.05, 0.05 - 0.10, 0.10 - 0.15, 0.15 - 0.20, 0.20 - 0.25, 0.25 - 0.30, or 0.30 - 0.33.

[0052] In some embodiments, the convex section radius of curvature R4 can range from about 1.0 inch to 9.0 inches. In one embodiment, the convex section radius of curvature R4 is about 2.5 inches. In other embodiments, the convex section radius of curvature R4 can be less than 8.0 inches, less than 7.0 inches, less than 6.0 inches, less than 5.0 inches, less than 4.0 inches, less than 3.5 inches, less than 3.0 inches, or less than 2.5 inches. For example, the convex section radius of curvature R4 can be about 1.0 inch, 2.0 inches, 2.5 inches, 3.0 inches, 4.0 inches, 5.0 inches, 6.0 inches, 7.0 inches, 8.0 inches, or 9.0 inches.

[0053] In some embodiments, the second concave section radius of curvature R5 can range from about 3.0 inches to 10.0 inches. In the illustrated embodiment, the second concave section radius of curvature R5 is about 6.0 inches. In other embodiments, the second concave section radius of curvature R5 can be less than 9.0 inches, less than 8.0 inches, less than 7.0 inches, less than 6.0 inches, or less than 5.0 inches. For example, the second concave section radius of curvature R5 can be about 3.0 inches, 4.0 inches, 5.0 inches, 6.0 inches, 7.0 inches, 8.0 inches, or 9.0 inches. In other embodiments, the sole curvature profile 166 of the club head 100 can also be determined by a polynomial, or a quadratic expression.

[0054] The recessed region 152 as described above allows the sole 112 of the club head 100 to follow a profile that curves much more sharply between the front end 106 and the rear end 108 compared to a prior art metalwood club head (i.e., the sole curvature profile results in a radius of curvature greater than 10 inches as it extends between the front end and the rear end). This makes it easier to produce a greater deflection in the sole 112 of the club body 102 when the club head 100 impacts a golf ball. The relatively large deflection of the club body 102 can result in a greater deflection of the club head 100 compared to a conventional metalwood golf club.

[0055] The golf club head 100 can increase the internal energy generated during impact to be between 1.0 lbf·inch and 8.0 lbf·inch, exceeding that of the club being compared. In some embodiments, the internal energy generated by the golf club head 200 during impact can be 1.0 lbf·inch, 2.0 lbf·inch, 3.0 lbf·inch, 4.0 lbf·inch, 5.0 lbf·inch, 6.0 lbf·inch, 7.0 lbf·inch, or 8.0 lbf·inch. This significant increase in internal energy results in an increase in ball speed by 0.1 mph, 0.2 mph, 0.3 mph, 0.4 mph, 0.5 mph, 0.6 mph, 0.7 mph, 0.8 mph, 0.9 mph, 1.0 mph, 1.1 mph, 1.2 mph, 1.3 mph, 1.4 mph, or 1.5 mph, which can in turn result in an increase in the flight distance of the golf ball between 1 yard and 10 yards. In some embodiments, the flight distance of the golf ball can increase by 1 yard, 2 yards, 3 yards, 4 yards, 5 yards, 6 yards, 7 yards, 8 yards, 9 yards, or 10 yards.

[0056] Furthermore, the relatively large deflection of the sole 112 during impact can result in a decrease in the ball spin speed generated on the golf ball during impact with the club head 100. For example, the spin speed can be decreased by approximately 150 revolutions per minute (RPM). In some embodiments, the spin speed can be decreased by 10 RPM, 20 RPM, 30 RPM, 40 RPM, 50 RPM, 60 RPM, 70 RPM, 80 RPM, 90 RPM, 100 RPM, 110 RPM, 120 RPM, 130 RPM, 140 RPM, or 150 RPM. In some examples, the ball spin speed can be decreased by 160 RPM, 170 RPM, 180 RPM, 190 RPM, or even 200 RPM.

[0057] III. Reverse-camber sole and internal curved beam Figures 5-7 illustrate a golf club head 200 according to another embodiment of the present invention. The golf club head 200 is similar to the golf club head 100 and includes substantially the same structure as the golf club head 100. Accordingly, the following description focuses primarily on the structures and features that are different from those of the above-described embodiment related to FIGS. 1-4. The features and elements described in connection with FIGS. 1-4 are designated with reference numerals in the 200s in FIGS. 5-7. It should be understood that the features of the golf club head 200 not explicitly described below have the same nature as the features of the golf club head 100.

[0058] Similar to the golf club head 100, the golf club head 200 includes a recessed area 252 (FIG. 5) formed in the sole 212. Referring to FIGS. 5 and 6, the golf club head 200 is attached to the sole 212 at a first end 291 and at a second end 292, and further includes an internal beam 290 that extends through the internal cavity 218 of the golf club head 200 between the first end 291 and the second end 292. In the illustrated embodiment, the golf club head 200 includes three beams 290. In other embodiments, the golf club head 200 may include one, two, four, five, six, seven, eight, nine, or ten beams 290.

[0059] The first end 291 of each beam 290 is attached to the sole 212 at a position proximate to the front end 206 of the golf club head 200. For example, in the illustrated embodiment, the first end 291 is attached to a portion of the sole 212 proximate to the face-sole transition boundary 256. The second end 292 of each beam 290 is attached to the sole 212 at or near the recessed area 252.

[0060] Each beam 290 extends in a generally fore-aft direction or in a direction along the generally Z-axis 1016. In some embodiments, each beam 290 follows a generally straight path between a first end 291 and a second end 292. In the illustrated embodiment, each beam 290 follows a curved path between a first end 291 and a second end 292. In particular, each beam 290 follows a generally arcuate path between a first end 291 and a second end 292. Further, in the illustrated embodiment, the beams 290 extend generally parallel to each other and each beam 290 follows a generally same arcuate path. In other embodiments, the beams 290 may follow respective paths that are different from each other between a first end 291 and a second end 292.

[0061] The beam height 293 of each beam 290 is defined as the maximum distance between the beam 290 and the inner surface of the sole 212, measured so as to be orthogonal to the inner surface of the sole. The beam height 293 can be in the range of 0.010 inches to 1.000 inches. In some embodiments, the beam height 293 can be in the range of 0.010 inches to 0.10 inches, 0.10 inches to 0.20 inches, 0.20 inches to 0.30 inches, 0.30 inches to 0.40 inches, 0.40 inches to 0.50 inches, 0.50 inches to 0.60 inches, 0.60 inches to 0.70 inches, 0.70 inches to 0.80 inches, 0.80 inches to 0.90 inches, or 0.90 inches to 1.0 inches. In some embodiments, the beam height 293 can be 0.10 inches, 0.20 inches, 0.30 inches, 0.40 inches, 0.50 inches, 0.60 inches, 0.70 inches, 0.80 inches, 0.90 inches, or 1.0 inches.

[0062] Referring to FIG. 7, each beam 290 includes a cross-sectional shape 294 defined such that the beam 290 is cut by a plane that extends so as to be orthogonal to the path of the beam 290. In the illustrated embodiment, the cross-sectional shape 294 of each beam 290 is rectangular. In other embodiments, the cross-sectional shape 294 of each beam 290 may be circular, triangular, rectangular, trapezoidal, octagonal, or any other desired cross-sectional shape.

[0063] In the embodiment shown, the cross-sectional shape 294 of each beam 290 includes a width 295 measured in a substantially heel-to-toe direction and a thickness 296 measured in a substantially crown-to-sole direction. The width 295 can range from about 0.010 inches to 1.000 inches. The width 295 can be 0.010 inches, 0.05 inches, 0.10 inches, 0.20 inches, 0.30 inches, 0.40 inches, 0.50 inches, 0.60 inches, 0.70 inches, 0.80 inches, 0.90 inches, or 1.0 inch. In the embodiment shown, the width 295 is about 0.2 inches.

[0064] The thickness 296 can range from about 0.010 inches to 0.500 inches. In some embodiments, the thickness 296 can be 0.010 inches, 0.015 inches, 0.020 inches, 0.025 inches, 0.030 inches, 0.035 inches, 0.040 inches, 0.045 inches, or 0.050 inches. In the embodiment shown, the thickness 296 is about 0.033 inches. Further, each beam 290 is spaced apart from each of the adjacent beams by about 0.5 inches.

[0065] In other embodiments, the beams 290 can be spaced apart from each other by a distance in the range of 0.050 inches to 1.000 inches. In some embodiments, the beams 290 can be spaced apart from each other by a distance of 0.010 inches, 0.015 inches, 0.020 inches, 0.025 inches, 0.030 inches, 0.035 inches, 0.040 inches, 0.045 inches, or 0.050 inches.

[0066] In some embodiments, the beams 290 can be formed from the same material as the body 204 of the club head 200 and can be integrally formed with the body 204. In other embodiments, the beams 290 can be formed separately from the body 204 and can be coupled to the body 204 by a coupling method such as welding, resin bonding, or any other suitable coupling method. In these embodiments, the beams 290 can be formed from the same or different material than the body 204 of the club head 200.

[0067] Figures 8 and 9 show a golf club head 300 according to another embodiment of the present invention. The golf club head 300 is similar to the golf club head 200 and includes substantially the same structure as the golf club head 200. Accordingly, the following description focuses primarily on the structures and features that are different from those of the above-described embodiment related to FIGS. 5-7. The features and elements described in connection with FIGS. 5-7 are labeled with reference numerals in the 300s in FIGS. 8 and 9. It should be understood that the features of the golf club head 300 not explicitly described below have the same nature as the features of the golf club head 200.

[0068] Similar to the golf club heads 100 and 200, the golf club head 300 includes a recessed region 352 formed in the sole 312. Also, similar to the golf club head 200, the golf club head 300 includes an internal beam 390 extending between a first end 391 and a second end 392. However, unlike the golf club head 200, the first end 391 of the beam 390 of the club head 300 is not attached to the sole 312. The first end 391 of each beam 390 is attached to the front end 306. In particular, the first end 391 of each beam 390 is attached to the outer edge 320 of the front end 306. Further, in the illustrated embodiment, the club head 300 includes four beams 390. In other embodiments, the club head 300 may include one, two, three, five, six, seven, eight, nine, or ten beams 290. The beams 390 of the club head 300 may follow any of the above-described paths associated with the club head 200. Similarly, the beams 390 may include a beam height 393, a cross-sectional shape 394, a width 395, and a thickness 396 similar to the above-described beam height 293, cross-sectional shape 294, width 295, and thickness 296 associated with the club head 200.

[0069] IV. Examples Example 1: Golf Club Head with Reverse Camber Sole Referring to FIGS. 10 - 12, there is shown a wood - type golf club head 400 including a sole 412 having a recess or concave region 452 where the sole 412 bends inwardly in a direction toward the internal cavity 418 of the club head 400. Thus, a typical wood includes a sole profile having a relatively large radius of curvature (i.e., a radius of curvature of about 22 - 25 inches) between the front end portion and the rear end portion. In contrast, the concave region 452 of the golf club head 400 allows the sole 412 to follow a profile that is much more sharply curved between the front end 406 and the rear end 408. Further, in the illustrated embodiment of the club head 400, no portion of the sole 412 includes a radius of curvature greater than 6 inches when viewed from a side cross - sectional view taken along the YZ plane 4022.

[0070] The above - mentioned concave region 452 allows the sole 412 of the club head 400 to follow a profile that is much more sharply curved between the front end 406 and the rear end 408 compared to a metal wood club head that does not include this profile. This makes it easier to generate a greater amount of deflection in the sole 412 of the club body 402 when the club head 400 strikes a golf ball. The greater deflection of the club body 402 generates a greater amount of internal energy within the club head 400 compared to a conventional metal wood golf club that does not include the concave region 452.

[0071] Referring to FIG. 13, the internal energy generated during impact by the golf club head 400 is compared with the internal energy generated during impact by a golf club head (hereinafter, the "club to be compared") that does not include the area sunken in the sole (where the sole profile has a relatively large radius of curvature between the front end and the rear end of the club). The sunken area 452 of the golf club head 400 results in an increase in the internal energy of the golf club head 400 of about 7.8 lbf inches over the club to be compared, thereby increasing the deflection. This 7.8 lbf inch increase in internal energy results in an increase in ball speed of about 1.0 mile per hour (mph) (at a swing speed of 100 mph), thereby lengthening the golf shot by at least 5 yards. Further, the sunken sole 412 of the golf club head 400 stores more vibrational energy in the golf club head immediately after impact, enabling a higher energy transfer from the golf club head 400 to the golf ball, thereby increasing the ball speed.

[0072] Furthermore, the sunken area 452 of the golf club head 400 improves the ball speed of shots struck below the center of the strike face. The greater deflection of the sunken sole 412 reduces the high backspin caused by low face strikes, resulting in a golf shot that flies farther than the club to be compared. The sunken area 452 in the sole 412 allows the front end 406 of the club head 400 to compress downward toward the ground surface and toward the rear end 408 of the golf club head 400 in a spring-like manner. This generates spring energy, delofts the golf club 400, thereby increasing the overall internal energy of the golf club 400 and reducing the spin speed.

[0073] Furthermore, the relatively large deflection of the sole 412 during impact can result in a decrease in the ball spin rate imparted to the golf ball upon impact with the club head 400 that exceeds that of the club being compared. In one embodiment, the spin rate can be decreased by up to 150 revolutions per minute (RPM). In some embodiments, the ball spin rate can be decreased from about 600 RPM to about 450 RPM. The combination of a faster ball speed and a lower spin rate generated by the greater deflection of the golf club head 400 results in a golf shot that is straighter and travels farther than the club being compared.

[0074] Example 2: Golf Club Head Comprising an Anti-Reverse Sole and an Internal Curved Beam In one embodiment, an exemplary golf club head 200 comprising an anti-reverse sole 212 (depressed region 252) and one or more internal curved beams 290 is being compared to a golf club head (hereinafter, the "club being compared") that includes a very flexible anti-reverse sole that does not include any internal curved beams. The one or more internal curved beams 290 function to partially stiffen and support the flexible bowed sole 212.

[0075] As described above, the anti-reverse sole 212 can increase internal energy and increase the resulting ball speed of the golf ball struck by the golf club head 200. However, for very fast golf swings, the anti-reverse sole 212 may require reinforcement (one or more internal curved beams 292) to prevent permanent deformation or breakage of the sole 212.

[0076] Compared to the club being compared, the exemplary golf club head 200 prevents some flexing in the sole 212 caused by the dimpled region 252. However, the golf club head 200 is not as flexible as the club being compared, but still allows significant overall flexing of the club head 200 and the striking face 204, thereby increasing the internal energy of the golf club head 200 while structurally reinforcing the sole 212.

[0077] In some embodiments, the exemplary golf club head 200 including the reverse camber sole 212 and one or more internal curved beams 290 can increase the internal energy generated during impact to between 1.0 lbf inches and 7.0 lbf inches beyond that of the club being compared. In some embodiments, the internal energy generated during impact by the golf club head 200 can be 1.0 lbf inches, 2.0 lbf inches, 3.0 lbf inches, 4.0 lbf inches, 5.0 lbf inches, 6.0 lbf inches, or 7.0 lbf inches. This significant increase in internal energy results in an increase in ball speed of 0.1 mph, 0.2 mph, 0.3 mph, 0.4 mph, 0.5 mph, 0.6 mph, 0.7 mph, 0.8 mph, 0.9 mph, or 1.0 mph, thereby increasing the carry distance of the golf ball by up to 5 yards.

[0078] The various features and advantages of the present disclosure are set forth in the claims that follow.

[0079] Clause 1: A hollow body golf club, comprising a body having a front end portion, a rear end portion opposite to the front end portion, a crown, a sole that is opposite to the crown and defines a sole surface, the sole being such that when the golf club head is in an address position for hitting a golf ball, a ground contact surface contacts the sole surface, the sole, a heel, a toe opposite to the heel, the hosel structure having a hosel axis extending through the center of a hole in the hosel structure, a strike face located at the front end portion and defining a geometric center and a loft plane in contact with the geometric center, the geometric center further defining a coordinate system having the geometric center, the coordinate system including an X-axis extending through the geometric center between the heel and the toe, a Y-axis extending through the geometric center between the crown and the sole and perpendicular to the X-axis, and a Z-axis extending through the geometric center between the front end portion and the rear end portion and perpendicular to the X-axis and the Y-axis, the Y-axis and the Z-axis together defining a YZ plane extending between the crown and the sole and between the front end portion and the rear end portion, the hollow body golf club further comprising a sole transition point defined by an intersection of the sole and the strike face, and a sole curvature profile defined by an intersection of the sole surface and the YZ plane, the sole curvature profile having a radius of curvature that changes as the sole curvature profile extends between the front end portion and the rear end portion, the radius of curvature being 10 inches or less when the sole curvature profile extends between the front end portion and the rear end portion.

[0080] Clause 2: A hollow body golf club head, comprising a body having a front end portion, a rear end portion on the opposite side of the front end portion, a crown, a sole on the opposite side of the crown, the sole defining a sole surface, a heel, a toe on the opposite side of the heel, a hosel structure having a hosel axis extending through the center of a hole in the hosel structure, a striking face located at the front end portion and defining a loft plane in contact with the geometric center and the geometric center, the geometric center further defining a coordinate system having an origin located at the geometric center, the coordinate system including an X-axis extending through the geometric center between the heel and the toe, a Y-axis extending through the geometric center between the crown and the sole and orthogonal to the X-axis, and a Z-axis extending through the geometric center between the front end portion and the rear end portion and orthogonal to the X-axis and the Y-axis, the X-axis and the Z-axis together defining an XZ plane extending between the heel end portion and the toe end portion and between the front end portion and the rear end portion, the Y-axis and the Z-axis together defining a YZ plane extending between the crown and the sole and between the front end portion and the rear end portion, the sole curvature profile being defined by the intersection of the sole surface and the YX plane, the sole curvature profile including a first concave section, a convex section, and a second concave section, the first concave section being located close to the front end portion and being concave with respect to the XZ plane, the second concave section being located close to the rear end portion and being concave with respect to the XZ plane, the convex section being located between the first concave section and the second concave section and being convex with respect to the XZ plane, the sole curvature profile further including an inflection point dividing the first concave section and the convex section, the club head defining an inflection point depth measured between the loft plane and the inflection point along a direction orthogonal to the loft plane, the club head defining a club head depth measured between the most distant range of the front end portion and the most distant range of the rear end portion in a direction parallel to the Z-axis, the inflection point depth ratio being defined as the ratio of the inflection point depth to the club head depth,The hollow body golf club head has an inflection point depth ratio between 0.25 and 0.45.

[0081] Clause 3: A hollow body golf club head comprising a body having a front end portion, a rear end portion opposite the front end portion, a crown, a sole opposite the crown, a heel, a toe opposite the heel, the hosel structure having a hosel axis extending through the center of a hole in the hosel structure, a strike face located at the front end portion and defining a loft plane that contacts the geometric center and the geometric center, the geometric center further defining a coordinate system having an origin located at the geometric center, the coordinate system including an X-axis extending through the geometric center between the heel and the toe, a Y-axis extending through the geometric center between the crown and the sole and orthogonal to the X-axis, and a Z-axis extending through the geometric center between the front end portion and the rear end portion and orthogonal to the X-axis and the Y-axis, the X-axis and the Z-axis together defining an XZ plane extending between the heel end portion and the toe end portion and between the front end portion and the rear end portion, the sole including a recessed region where the sole extends toward the XZ plane, the recessed region defining a deepest portion extending closest to the XZ plane along a direction orthogonal to the XZ plane, the club head defining a depth of the deepest portion measured between the loft plane and the deepest portion along a direction orthogonal to the loft plane, the club head defining a club head depth measured between the most distant range of the front end portion and the most distant range of the rear end portion in a direction parallel to the Z-axis, the depth ratio of the deepest portion being defined as the ratio of the depth of the deepest portion to the club head depth, the depth ratio of the deepest portion being between 0.45 and 0.60, a hollow body golf club head.

[0082] Clause 4: The radius of curvature includes a first inflection point and a second inflection point. The sole curvature extends from the sole transition point to the first inflection point and is a first concave section that is concave with respect to the XZ plane, extends from the first inflection point to the second inflection point and is a convex section that is convex with respect to the XZ plane, and extends from the second inflection point to the rear end portion and is a second concave section that is concave with respect to the XZ plane. The golf club head according to Clause 1.

[0083] Clause 5: The first concave section has a radius of curvature (R3), the convex section has a radius of curvature (R4), and the second concave section has a radius of curvature (R5). The golf club head according to Clause 4.

[0084] Clause 6: The sole curvature profile includes a heel portion, and the heel portion represents the point on the sole curvature profile closest to the XZ plane. The heel portion is located on the convex portion. The golf club head according to Clause 5.

[0085] Clause 7: The heel portion has a heel height, and the heel height is measured vertically from the ground contact surface to the heel portion. The golf club head according to Clause 6.

[0086] Clause 8: The heel height is inversely proportional to the radius of curvature (R3) of the first concave section. The golf club head according to Clause 7.

[0087] Clause 9: Further includes a heel height ratio, and the heel height ratio is defined as the ratio of the heel height to the radius of curvature (R3) of the first concave section. The golf club head according to Clause 8.

[0088] Clause 10: The heel height ratio is less than 0.33. The golf club head according to Clause 9.

[0089] Clause 11: The heel height ratio is between 0.001 and 0.05. The golf club head according to Clause 10.

[0090] Clause 12: The golf club head according to clause 5, wherein the curvature radii R3 and R5 are not less than R4.

[0091] Clause 13: The golf club head according to clause 5, wherein the curvature radius R3 is at least twice as large as the curvature radius R4.

[0092] Clause 14: The golf club head according to clause 8, further comprising a depth and a back depth, wherein the depth of the club head is measured as the farthest point from the front end portion to the rear end portion in a direction parallel to the Z axis, and the back depth is measured perpendicularly from the loft plane to the back portion.

[0093] Clause 15: The golf club head according to clause 14, further comprising a back depth ratio, wherein the back depth ratio is defined as the ratio of the back depth to the depth of the club head.

[0094] Clause 16: The golf club head according to clause 15, wherein the back depth ratio is greater than 0.35.

[0095] Clause 17: The golf club head according to clause 16, wherein the back depth ratio is between 0.40 and 0.60.

[0096] Clause 18: The golf club head according to clause 5, wherein the curvature radius R5 is greater than 10 inches.

[0097] Clause 19: The golf club head according to clause 15, wherein the first inflection point has a depth, and the first inflection point depth is measured between the loft plane and the first inflection point along a direction perpendicular to the loft plane.

[0098] Clause 20: The golf club head according to clause 19, further comprising an inflection point depth ratio, wherein the inflection point depth ratio is defined as the ratio of the first inflection point depth to the depth of the club head.

[0099] Clause 21: The golf club head according to Clause 20, wherein the inflection point depth ratio is greater than 0.25.

[0100] Clause 22: The golf club head according to Clause 21, wherein the inflection point depth ratio is between 0.25 and 0.45.

[0101] The substitution of an element recited in one or more claims constitutes a reconstruction and not a repair. Further, benefits, other advantages, and solutions to problems are described in connection with specific embodiments. However, a benefit, advantage, solution to a problem, and any element or elements that may cause or clarify any benefit, advantage, or solution are not construed as important, necessary, or essential features or elements of any or all of the claims unless such benefit, advantage, solution, or element is expressly recited in any or all of the claims.

[0102] Golf rules can change from time to time (e.g., new rules may be adopted, or old rules may be excluded or changed by golf standard organizations and / or governing bodies such as the United States Golf Association (USGA), the Royal and Ancient Golf Club of St. Andrews (R&A), etc.). Thus, golf equipment related to the devices, methods, and products described herein may or may not conform to the golf rules at any given point in time. Accordingly, golf equipment related to the devices, methods, and products described herein may be advertised, offered for sale, and / or sold as conforming or non-conforming golf equipment. The devices, methods, and products described herein are not limited in this regard.

[0103] The above example can be described in relation to a wood-type golf club, but the apparatus, methods, and products described herein are applicable to various types of golf clubs, including drivers, fairway woods, hybrids, crossovers, or any hollow body-type golf club.

[0104] Furthermore, the embodiments and limitations disclosed herein are not dedicated to the public under the doctrine of equivalents where the embodiments and / or limitations are (1) not expressly recited in the claims, and (2) are or may be equivalents of elements and / or limitations expressly recited in the claims.

[0105] Although the invention has been described in detail with reference to certain preferred embodiments, variations and modifications exist within the scope and spirit of one or more of the independent aspects of the invention as described.

Claims

Claim 1 A hollow golf club head, comprising a body having a front end portion, a rear end portion on the opposite side of the front end portion, a crown, a sole on the opposite side of the crown, defining a sole surface, wherein when the golf club head is in an address position for hitting a golf ball, a ground contact surface contacts the sole surface, the sole, a heel, a toe on the opposite side of the heel, the hosel structure having a hosel axis extending through the center of a hole in the hosel structure, an internal cavity, a striking face located at the front end portion, defining a geometric center and a loft plane contacting the geometric center, the geometric center further defining a coordinate system having the geometric center, the coordinate system comprising an X axis extending through the geometric center between the heel and the toe, a Y axis extending through the geometric center between the crown and the sole, perpendicular to the X axis, a Z axis extending through the geometric center between the front end portion and the rear end portion, perpendicular to the X axis and the Y axis, the X axis and the Z axis together defining an XZ plane extending between the heel and the toe and between the front end portion and the rear end portion, the Y axis and the Z axis together defining a YZ plane extending between the crown and the sole and between the front end portion and the rear end portion, the golf club head further comprising a dented region defined as a location where the sole bends inward in a direction toward the internal cavity, a sole transition point defined by an intersection of the sole and the striking face, the dented region comprising a sole curvature profile defined by an intersection of the sole surface and the YZ plane, the sole curvature profile comprising a first inflection point and a second inflection point, the sole curvature profile comprising a first concave section extending from the sole transition point to the first inflection point, concave with respect to the XZ plane, a convex section extending from the first inflection point to the second inflection point, convex with respect to the XZ plane, a second concave section extending from the second inflection point to the rear end portion, concave with respect to the XZ plane, the first concave section having a radius of curvature (R3), the convex section having a radius of curvature (R4), The second concave section has a radius of curvature (R5), The sole curvature profile further includes a depth and a depth ratio of the depth, The depth represents the point on the sole curvature profile closest to the XZ plane, The depth is located on the convex section, The depth ratio of the depth is defined as the ratio of the depth of the depth to the depth of the golf club head, The depth ratio of the depth is between 0.40 and 0.50, The golf club head, The golf club head further includes a face-sole transition profile located at the location where the striking face transitions to the sole and having a face-sole transition radius of curvature, The face-sole transition radius of curvature is less than 0.5 inches, A golf club head in which any part of the sole cut by the YZ plane does not include a radius of curvature greater than 10 inches between the front end portion and the rear end portion.

2. The golf club head according to claim 1, wherein the depth of the depth is greater than 1.5 inches.

3. The golf club head according to claim 1, wherein the depth of the depth is greater than 2 inches.

4. The golf club head according to claim 1, wherein the depth of the depth is greater than 2.5 inches.

5. The golf club head according to any one of claims 1 to 4, wherein the depth ratio of the depth is between 0.45 and 0.

50.

6. The golf club head according to any one of claims 1 to 5, wherein the depth of the depth is between 2.5 and 3.0 inches.

7. The golf club head according to any one of claims 1 to 6, wherein the volume of the golf club head is greater than 400 cc.

8. The golf club head according to any one of claims 1 to 7, wherein the radius of curvature (R3) and the radius of curvature (R5) are equal to or greater than the radius of curvature (R4).

9. The golf club head according to any one of claims 1 to 8, wherein the radius of curvature (R3) is at least twice the radius of curvature (R4).

10. A hollow golf club head, A body having a front end portion, A rear end portion on the opposite side of the front end portion, A crown, A sole on the opposite side of the crown that defines a sole surface, wherein when the golf club head is in an address position for hitting a golf ball, the ground contact surface contacts the sole surface, the sole, A heel, a toe opposite the heel; a hosel structure having a hosel axis extending through a center of a hole in the hosel structure; An internal cavity and a strike face located at the front end and defining a geometric center and a loft plane tangent to the geometric center; the geometric center further defines a coordinate system having the geometric center; The coordinate system is an X-axis extending through the geometric center between the heel and the toe; a Y-axis extending between the crown and the sole through the geometric center and perpendicular to the X-axis; a Z-axis extending through the geometric center between the front end and the rear end and perpendicular to the X-axis and the Y-axis; the X-axis and the Z-axis together define an XZ plane extending between the heel and the toe and between the front end and the rear end; the Y-axis and the Z-axis together define a YZ plane extending between the crown and the sole and between the front end and the rear end; The golf club head comprises: a concave region defined as where the sole bends inward toward the interior cavity; a sole transition point defined by an intersection of the sole and the strike face; the recessed region comprises a sole curvature profile defined by the intersection of the sole surface and the YZ plane; the sole curve profile includes a first inflection point and a second inflection point; The sole curvature profile is a first concave section extending from the sole transition point to the first inflection point and concave with respect to the XZ plane; a convex section extending from the first inflection point to the second inflection point and convex with respect to the XZ plane; a second concave section extending from the second inflection point to the rear end and concave with respect to the XZ plane; the first concave section has a radius of curvature (R3); the convex section has a radius of curvature (R4); the second concave section has a radius of curvature (R5); The sole curve profile further comprises a depth, a depth depth ratio, and a depth height ratio, the deepest part represents the point on the sole curve profile closest to the XZ plane; the recessed portion is located on the convex section; the depth-height ratio is defined as the ratio of the depth height to the radius of curvature (R3) of the first concave section; The back depth ratio is less than 0.33, The back depth ratio is defined as the ratio of the depth of the back to the depth of the golf club head, The back depth ratio is between 0.40 and 0.60, for a golf club head.

11. The depth of the back is greater than 1.5 inches, for the golf club head according to claim 10.

12. The depth of the back is greater than 2 inches, for the golf club head according to claim 10.

13. The depth of the back is greater than 2.5 inches, for the golf club head according to claim 10.

14. The back depth ratio is between 0.45 and 0.60, for the golf club head according to any one of claims 10 to 13.

15. The depth of the back is between 2.5 and 3.0 inches, for the golf club head according to any one of claims 10 to 14.

16. The back height ratio is less than 0.30, for the golf club head according to any one of claims 10 to 15.

17. The radius of curvature (R3) and the radius of curvature (R5) are equal to or greater than the radius of curvature (R4), for the golf club head according to any one of claims 10 to 16.

18. The radius of curvature (R3) is at least twice the radius of curvature (R4), for the golf club head according to any one of claims 10 to 17.

19. The radius of curvature (R5) is greater than 10 inches, for the golf club head according to any one of claims 10 to 18.

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