Golf club head

Abstract

A golf club head includes a volume greater than 400 cubic centimeters, a crown portion, a sole portion opposite the crown portion, a toe portion, a heel portion portion opposite the toe portion, and a striking face. The striking face includes a face center, a first point located laterally toe-ward from the face center by a first distance D1 between 25 mm and 35 mm, the first point associated with a first loft, a first bulge radius, and a first roll radius, and a second point located laterally heel-ward from the face center by the first distance D1, the second point associated with a second loft that is less than the first loft by at least 0.5 degrees, a second bulge radius that is within 0.2 in of the first bulge radius, and a second roll radius that is within 0.2 in of the first roll radius.

Description

[0001] This application is a non-provisional of Provisional Application No. 63 / 664,918, filed on Jun. 27, 2024, the contents of which is incorporated by reference herein in its entirety.BACKGROUND

[0002] The performance of golf clubs is evaluated on the basis of many factors, which vary dependent on the type of club. When evaluating wood-type golf clubs, golfers tend to value distance and accuracy as the most important factors.

[0003] Often, golf clubs may be designed to perform well under ideal conditions including for impacts at an ideal location on the striking face. However, evaluating performance under ideal conditions alone may not result in a golf club that performs well for a particular golfer overall. For example, golf clubs, particularly wood-type clubs, are often designed such that impacts at or near a face center lead to most effective overall results. However, such a principle may not be realistic, particularly for some classes of golfer.

[0004] Furthermore, when a golf ball is struck off-center, the clubface tends to impart spin on a golf ball in a direction opposite to the direction of the off-center impact on the clubface. Such an effect is commonly referred to as “gear effect”. Gear effect occurs due to the curvature of the clubface and the resulting interaction between the clubface and the golf ball during impact.

[0005] When a golf ball is struck off-center on the club face, the clubface imparts both linear and rotational forces on the ball. If the impact occurs towards the toe-side of an ideal impact location of the clubface, the golf ball tends to rotate counterclockwise (assuming a right-handed player and when viewing the club face and golf ball in a top-down view). If the impact occurs towards the heel-side of an ideal impact location of the clubface, the golf ball tends to rotate clockwise.

[0006] The club face of a wood-type golf club head is often designed with bulge and roll to help minimize adverse effects of off-center hits. Incorporating curvature on the club face enables deviation in trajectory to counteract the spin-induced bias generated by off-center hits. Bulge refers to the curvature in a heel-to-toe direction, while roll refers to the curvature in a crown-to-sole direction. Bulge and roll can help reduce the severity of gear effect for off-center impacts. However, gear effect still plays a significant role in shaping the trajectory of shots, especially with wood-type golf club heads that have a larger club face, such as drivers.SUMMARY

[0007] An object, therefore, of the present disclosure is to provide a golf club head that includes a club face that is designed to maximize distance and accuracy by reducing gear effect for off-center impacts.

[0008] In one aspect of the present disclosure, a golf club head includes a volume greater than 400 cubic centimeters, a crown portion, a sole portion opposite the crown portion, a toe portion, a heel portion portion opposite the toe portion, and a striking face. The striking face includes a face center, a first point located laterally toe-ward from the face center by a first distance D1 between 25 mm and 35 mm, the first point associated with a first loft, a first bulge radius, and a first roll radius, and a second point located laterally heel-ward from the face center by the first distance D1, the second point associated with a second loft that is less than the first loft by at least 0.5 degrees, a second bulge radius that is within 0.2 in of the first bulge radius, and a second roll radius that is within 0.2 in of the first roll radius.

[0009] In another aspect of the present disclosure, a golf club head, when oriented in a reference position relative to a virtual ground plane includes a volume greater than 400 cubic centimeters, a crown portion, a sole portion opposite the crown portion, a toe portion, a heel portion opposite the toe portion, and a striking face. The striking face includes a face center, such that a virtual horizontal plane passes through the face center, a first point located laterally toe-ward from the face center by a distance D1 between 25 mm and 35 mm and located vertically above the virtual horizontal plane by a distance D2 between 5 mm and 15 mm, the first point associated with a first loft and a first roll radius, and a second point located laterally heel-ward from the face center by the distance D1 and located vertically above the virtual horizontal plane by the distance D2, the second point associated with a second loft that is less than the first loft by at least 1 degree and a second roll radius that is greater than the first roll radius by at least 5 in.

[0010] In another aspect of the present disclosure, a golf club head, when oriented in a reference position relative to a virtual ground plane includes a volume greater than 400 cubic centimeters, a crown portion, a sole portion opposite the crown portion, a toe portion, a heel portion opposite the toe portion, and a striking face. The striking face includes a face center, such that a virtual horizontal plane passes through the face, a first point located laterally toe-ward from the face center by a distance D1 between 25 mm and 35 mm and located vertically below the virtual horizontal plane by a distance D2 between 5 mm and 15 mm, the first point associated with a first loft and a first roll radius, and a second point located laterally heel-ward from the face center by the distance D1 and located vertically below the virtual horizontal plane by the distance D2, the second point associated with a second loft that is less than the first loft by at least 1 degree and a second roll radius that is that is greater than the first roll radius by at least 5 in.

[0011] These and other features and advantages of the golf club heads, their implementations, and the methods of manufacture thereof according to the various aspects of the present disclosure will become more apparent upon consideration of the following description, drawings, and appended claims. The description and drawings described below are for illustrative purposes only and are not intended to limit the scope of the present invention in any manner.BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The drawings described below are for illustrative purposes only and are not intended to limit the scope of the present invention in any way. Exemplary implementations will now be described with reference to the accompanying drawings, wherein:

[0013] FIG. 1 shows a front elevation view of an exemplary golf club head in accordance with one or more aspects of the present disclosure.

[0014] FIG. 2 illustrates a perspective view of an exemplary golf club head with an example coordinate system in accordance with one or more aspects of the present disclosure.

[0015] FIGS. 3A-D illustrate coordinate maps of an example striking face of a golf club head in accordance with one or more aspects of the present disclosure.

[0016] FIGS. 4A-D illustrate coordinate maps of another example striking face of a golf club head in accordance with one or more aspects of the present disclosure.

[0017] FIGS. 5A-D illustrate coordinate maps of a further example striking face of a golf club head in accordance with one or more aspects of the present disclosure.

[0018] FIGS. 6A-D illustrate coordinate maps of a further example striking face of a golf club head in accordance with one or more aspects of the present disclosure.

[0019] FIGS. 7A-D illustrate coordinate maps of a further example striking face of a golf club head in accordance with one or more aspects of the present disclosure.

[0020] FIG. 8A-D illustrate coordinate maps of a further example striking face of a golf club head in accordance with one or more aspects of the present disclosure.

[0021] FIG. 9 shows a front elevation view of an exemplary golf club head in accordance with one or more aspects of the present disclosure.

[0022] FIG. 10 shows a heel side view of an exemplary golf club head in accordance with one or more aspects of the present disclosure.

[0023] FIGS. 11A-D illustrate coordinate maps of an example striking face of a golf club head in accordance with one or more aspects of the present disclosure.

[0024] FIG. 12 depicts simulated test data for various striking faces described in accordance with one or more aspects of the present disclosure.DETAILED DESCRIPTION

[0025] In some aspects of the present disclosure, referring to FIG. 1, a golf club head 10 is shown. The golf club head 10 includes a crown portion 12 (or top portion) and a sole portion 14 opposite the crown 12. The golf club head 10 further includes a toe portion 16 and a heel portion 18 opposite the toe portion 16. The golf club head 10 also includes a striking face 20 and a hosel 22 that extends from the heel portion 18. The hosel 22 includes an internal hosel bore 24 configured to receive a shaft (not shown) therein. The internal hosel bore 24 defines a central axis, i.e., a hosel axis 26.

[0026] The striking face 20 is generally planar (or quasi-planar), but includes curvature of relatively high radius (i.e., no less than 6 in). Furthermore, the striking face 20 includes bulge and roll curvature. Bulge refers to the curvature of the striking face 20 in a generally heel-to-toe direction, while roll refers to the curvature of the striking face in a generally top-to-bottom direction. In some examples, the bulge and / or roll of the striking face may be of substantially constant radius across the striking face 20. However, in other examples, the bulge and / or roll may vary in radius across the striking face 20 in a vertical direction and / or a horizontal direction.

[0027] The striking face 20 is delimited by a striking face periphery 28. The striking face periphery 28 is defined by the loci of points circumscribing the quasi-planar region that defines the striking face 20, as described above. In some examples, the striking face periphery 28 may be readily ascertainable, such as by the presence of abrupt change in contour forming an angled peripheral edge. However, in other examples, the transition from the striking face 20 to a main body of the golf club head 10 may be less visually discernible. In such examples, the striking face periphery 28 is understood to be the loci of point circumscribing the quasi-planar striking face 20 where transition occurs from a high radius of curvature to a low radius of curvature (i.e., less than 4 in.).

[0028] The golf club head 10 shown and described herein may include various configurations of different striking faces that minimize and / or reduce the gear effect for golf ball impact across the striking face and / or for golf ball impacts on a specific region of the striking face 20. Such configurations may: improve dispersion of shots compared to a standard striking face and / or improve carry distance of shots compared to a standard striking face. These and other improvements will be described further herein below with respect to the various configurations described herein.

[0029] The golf club head 10 is shown in a reference position. As used herein, “reference position”, refers to a position of the golf club head 10 where the hosel axis 26 is oriented at a lie angle of about 60° (+ / −5° depending on the particular configuration of the hosel) with respect to a virtual ground plane 30, and lies in a virtual vertical hosel plane 27 (shown in FIG. 1), which contains an imaginary horizontal line generally parallel to the striking face 20. Unless state otherwise, attributes of the golf club head 10 described herein are presumed to apply to the golf club head 10 as oriented in a reference position.

[0030] The striking face 20 of the golf club head 10 includes a face center 32. For all purposes herein, “face center” (e.g., face center 32) refers to a point on a striking face of a golf club head that is simultaneously: (a) laterally equidistant from the heel-side and toe-side of the periphery of the striking face 20; and (b) vertically equidistant from the top-side and the sole-side of the periphery of the striking face 20 of the golf club head 20.

[0031] From a practical standpoint, face center (e.g., face center 32, as shown in FIG. 1) may be determined in accordance with the United States Golf Association's Procedure for Measuring the Flexibility of a Golf Clubhead (Revision 2.0, Mar. 25, 2005) available from the USGA. Specifically, a standard template is used that has a coordinate system with a heel-toe axis orthogonal to a top-bottom axis. An aperture is disposed at the origin of the coordinate system, with the axes being graduated into evenly spaced increments. The template may be made of a flexible material, e.g., a transparent polymer. The location of the face center, e.g. face center 32, is determined by initially applying the template to the striking face 20 so that the aperture is approximately in the middle of the striking face 20 and the heel-toe axis is generally horizontal. The template is then translated in the heel-toe direction along the striking face 20 until the heel and toe measurements along the axis at opposite points on the striking face perimeter of the striking face 20 proximate respective ones of the toe and heel portions 16 and 18 have the same absolute value. Once the template is centered with respect to the striking face 20 in the heel-toe direction, the template is translated into the top-bottom direction along the striking face 20 until the measurements along the axis at opposite points on the striking face perimeter of the striking face 20 proximate respective ones of the top and bottom portions 12 and 14 have the same absolute value. The above sequence is repeated until the absolute value of the heel measurement along the axis is equal to that of the toe measurement and the absolute value of the bottom measurement along axis is equal to that of the top measurement. A point is then marked on the striking face 20 through the aperture to designate the face center 32.

[0032] As mentioned previously, the golf club head 10 is a wood-type club head. Preferably, the golf club head 10 is a driver-type club head (e.g., configured to impact a golf ball off a tee and / or has a loft that is less than 15 degrees). Accordingly, the golf club head 10 preferably has a volume no less than 390 cubic centimeters (cc), more preferably between about 410 cc and 470 cc, even more preferably between about 440 cc and 465 cc. Additionally, or alternatively, the golf club head 10 has a head mass no less than 170 g, more preferably no less than 185 g, and even more preferably within the range of about 185 g to 210 g. In some examples, the golf club head 10 may be a miniature-type driver having a volume between about 250 cc and 350 cc and having a mass between about 175 g to 250 g. Furthermore, in some examples, the golf club head 10 may include fairway and / or hybrid type golf club heads. For example, the golf club head 10 may have a volume between about 120 cc and 220 cc for fairway-type golf club heads and between about 75 cc and 150 cc for hybrid-type golf club heads. Additionally, the golf club head 10 may have a mass between about 190 g to 250 g for fairway-type golf club heads and between about 200 g to 275 g for hybrid-type golf club heads.

[0033] Further shown in FIG. 1 are a virtual Y-axis and a virtual Z-axis. The origin of the virtual Y-axis and the virtual Z-axis coincides with the face center 32. With the golf club head 10 in the reference position, the Y-axis extends in a sole to crown direction and tangent to the face center 32. A positive Y-axis corresponds with a sole 14 to crown 12 direction, thus positive y values correspond with locations crown-ward of the face center 32 and negative y values correspond with locations sole-ward of the face center 32. The Z-axis extends in a direction parallel to the virtual ground plane 30 and tangent the face center 32. Furthermore, a positive Z-axis direction corresponds with a heel to toe direction such that locations toe-ward of the face center 32 have positive z values and locations heel-ward of the face center 32 have negative z values.

[0034] FIG. 2 illustrates a perspective view of the golf club head 10 having a coordinate system, as described previously. Further shown in FIG. 2 is a virtual X-axis that is normal to the striking face 20 at the face center 32 (i.e., the origin of the coordinate system). A positive X-axis direction corresponds with a forward direction such that locations forward of the origin, i.e. the face center 32, have positive x values and locations rearward of the face center 32 have negative x values. In some examples, the striking face 20 surface x(y, z) may be represented as a second order polynomial surface with 9 parameters (p0, p1, . . . , p8):x⁡(y,z)=p0+p1⁢z+p2⁢z2+p3⁢y+p4⁢y⁢z+p5⁢y⁢z2+p6⁢y2+p7⁢y2⁢z+p8⁢y2⁢z2

[0035] Using various ranges for the parameters p, the second order polynomial surface equation describes a variety of clubface curvatures. For example, setting p2<0 and p6<0 and setting the remaining parameters to zero creatures a standard striking face curvature that includes substantially constant bulge and roll, where p2 controls the bulge and p6 controls the roll. As such, the polynomial surface equation may be used to characterize various striking face 20 curvatures, as described further herein below. It should be noted that when parameters are omitted from the polynomial surface equation, such parameters are assumed to be equal to zero. In some examples, the golf club head 10 includes an overall or effective club head loft between approximately 4 degrees and approximately 15 degrees. The overall or effective club head loft is defined as an angle (θ shown in FIG. 2) between the face center 32 (or proximate the face center) of the striking face and a virtual vertical plane 33 when the golf club head is in the reference position. While the golf club head 10 includes an overall club head loft, the striking face 20 may include actual loft that varies as a function of face location. Such variation of actual loft of the striking face 20 is due to the roll curvature of the striking face 20. As such, when discussing actual loft characteristics of the striking face 20, it is assumed that the actual loft is described relative to the overall loft of the golf glub head 10. In order to measure actual loft at a desired measurement point, a loft and lie angle measurement device for wood-type club heads may be used. To measure loft at a desired measurement point, two vertical pins are used to measure the loft about the desired point which is equidistant between the two vertical pins.

[0036] FIGS. 3A-D illustrate coordinate maps of an example striking face 34 of a golf club head. The coordinate maps depict the striking face 20 such that the origin (i.e., 0,0 on the coordinate map) corresponds with the face center 32 and the origin has a relative loft of 0 and a relative face angle of 0, while the remaining locations of the striking face 20 are angularly offset relative to the origin. The coordinate map is further defined by the Y and Z axes shown and described in FIGS. 1 and 2. It is noted that the specific values shown on the coordinate maps are not limiting and merely show exemplary values for the inventive striking faces described herein. The specific values shown may also vary due to mathematical rounding and the relative values shown on the coordinate maps are not limiting and are merely exemplary. Specific values and ranges thereof will be described further herein below.

[0037] In some examples and following the second order polynomial surface equation described above, the striking face 34 may be defined using separate equations to represent the top half (y>0) and the bottom half (y≤0) of the striking face 34. As such, the striking face 34 may be defined by a piecewise equation as follows:x⁡(y, z)={p2⁢z2+p6⁢y2+p7⁢y2⁢zy>0p2⁢z2+p6⁢y2y≤0⁢ andp2<0,p6<0,p7<0

[0038] As shown in FIG. 3B, the striking face 34 includes an upper half (y>0) that has varying roll. For example, on the upper half (y>0) of the striking face 34, the roll radius on the heel side (z<0) is greater than the roll radius on the toe side (z>0). In some examples, the roll radius of the top half (y>0) of the striking face may vary between approximately 5 in. and 24 in, or preferably between approximately 6 in. and 22 in. Additionally, the roll radius along the Z-axis is substantially constant. In the provided example, the roll radius along the Z-axis may be approximately 10 in. However, it is to be understood that the specific values may vary. Additionally, in some examples, the roll radius and the bulge radius of the bottom half (y≤0) of the club face are also substantially constant.

[0039] As shown in FIG. 3C, the top half (y>0) of the striking face includes a loft on the toe side (z>0) that is greater than the loft of the heel side (z<0) for the same value of y. Additionally, the loft of the striking face 34 along the Z-axis is substantially equal to the loft at the origin (0,0). In some examples, the average added loft of the striking face 34 of the golf club head is 0.

[0040] Furthermore, and as shown in FIG. 3D, the top half (y>0) of the striking face 34 includes an open face angle, while the bottom half (y≤0) of the striking face 34 is neutral directly below the origin (0,0) along the Y-axis. In such an example, the average face angle of the entire striking face 34 is open.

[0041] To illustrate, the striking face 34 includes a first point (P1) located laterally toe-ward from the face center (0,0) along the Z-axis by a distance D1 between 25 mm and 35 mm and located vertically above the Z-axis in the Y-axis direction by a distance between 5 mm and 15 mm. The first point P1 is associated with a first loft and a first roll radius. The striking face 34 also includes a second point (P2) located laterally heel-ward from the face center (0,0) along the Z-axis by the distance D1 and located vertically above the Z-axis in the Y-axis direction by the distance D2. The second point P2 is associated with a second loft that is less than the first loft by at least 1 degree, and preferably at least 2 degrees. The second point is also associated with a second roll radius that is greater than the first roll radius by at least 5 in, preferably at least 7 in, and more preferably at least 10 in.

[0042] Following the example above, the striking face 34 may further include a third point P3 located laterally toe-ward from the face center (0,0) along the Z-axis by a distance D3 between 25 mm and 35 mm. The third point P3 is associated with a third loft that is less than the first loft. The third point P3 is also associated with a third roll radius that is greater than the first roll radius and less than the second roll radius. The striking face 34 may further include a fourth point P4 located laterally heel-ward from the face center (0,0) along the Z-axis by the distance D3. The fourth point P4 is associated with a fourth loft that is within 0.2 degrees or preferably within 0.1 degrees of the third loft. The fourth point P4 is also associated with a fourth roll radius that is within 0.5 in. or preferably within 0.2 in. of the third roll radius.

[0043] In some examples, the face center (0,0) is associated with a first face angle and a fifth roll radius. In such an example, the striking face 34 further includes a fifth point P5 located vertically below the center (0,0) along the Y-axis by a distance D5 between 5 mm and 20 mm. The fifth point P5 is associated with a second face angle that is within 0.2 degrees or preferably within 0.1 degree of the first face angle. The fifth point P5 is also associated with a sixth roll radius that is within 0.2 in. or preferably within 0.1 in. of the fifth roll radius. In some examples, a roll radius for at least 90%, preferably at least 95%, and more preferably greater than 95% of locations occupying the striking face below the virtual Z-axis is within 0.2 in. or preferably within 0.1 in. of the fifth roll radius.

[0044] The striking face 34 shown and described in FIGS. 3A-D may provide various benefits over a standard striking face. For example, the striking face 34 may provide improved shot dispersion when compared with a standard striking face. Furthermore, for impacts above the Z-axis, the striking face 34 will impart less draw spin (assuming a right-handed player), which results in straighter shots. Such a characteristic may prevent a “snap hook” that commonly occurs with a high-toe impact. Furthermore, for impacts below the Z-axis, the striking face 34 may launch a golf ball right of a target line. As such, the striking face 34 may be beneficial to a particular subset of players who may tend to hook the golf ball. Simulated test data of the striking face 34 is further described with respect to FIG. 12 below.

[0045] Furthermore, the striking face 34 may provide various benefits over other striking faces that attempt to reduce gear effect. For example, the striking face 34 described herein minimizes complex variability to regions of greatest impact for a subset of players. This provides a unique advantage over other striking faces that attempt to minimize gear effect. For example, the striking face 34 may minimize complex variability, reducing overall precision required in polishing, and / or reducing cost in forming such a striking face 34. As such, the striking face 34 described herein is effective to not overburden manufacturing resulting in a striking face 34 that effectively reduces gear effect.

[0046] FIGS. 4A-D illustrate coordinate maps of an example striking face 36 of a golf club head. As may be apparent from the figures, the striking face 36 shown in FIGS. 4A-D may be substantially inverse from the striking face 34 shown in FIGS. 3A-D. The coordinate maps depict the striking face 36 tilted relative to the plane defined by the Y and Z axes such that the origin (i.e., 0,0 on the coordinate map) has a loft of 0 and a face angle of 0. It is noted that the specific values shown on the coordinate maps are not limiting and merely show exemplary values for the inventive striking faces described herein. The specific values shown may also vary due to mathematical rounding and the relative values shown on the coordinate maps are not limiting and are merely exemplary. Specific values and ranges thereof will be described further herein below.

[0047] In some examples and following the second order polynomial surface equation described above, the striking face 36 may be defined using separate equations to represent the top half (y>0) and the bottom half (y≤0) of the striking face 36. As such, the striking face 36 may be defined by a piecewise equation as follows:x⁡(y, z)={p2⁢z2+p6⁢y2y>0p2⁢z2+p6⁢y2+p7⁢y2⁢zy≤0⁢ andp2<0,p6<0,p7>0

[0048] As shown in FIG. 4B, the striking face 36 includes a bottom half (y≤0) that has varying roll. For example, on the bottom half (y≤0) of the striking face, the roll radius on the toe side (z>0) is greater than the roll radius on the heel side (z<0). In some examples, the roll radius of the bottom half (y≤0) of the striking face may vary between approximately 5 in. and 24 in, or preferably between approximately 6 in. and 22 in. Additionally, the roll radius along the Z-axis is substantially constant. In the provided example, the roll radius along the Z-axis may be approximately 10 in. However, it is to be understood that the specific values may vary. Additionally, in some examples, the roll radius and the bulge radius of the top half (y>0) of the club face are also substantially constant.

[0049] As shown in FIG. 4C, the bottom half (y≤0) of the striking face 36 includes a loft on the heel side (z<0) that is less than the loft of the toe side (z>0) for the same value of y. Additionally, the loft of the striking face 36 along the Z-axis is substantially equal to the loft at the origin (0,0). In some examples, the average added loft of the striking face 36 of the golf club head is 0.

[0050] Furthermore, and as shown in FIG. 4D, the bottom half (y≤0) of the striking face 36 includes a closed face angle, while the top half (y>0) of the striking face 34 is neutral directly above the origin (0,0) along the Y-axis. In such an example, the average face angle of the entire striking face 36 is closed.

[0051] To illustrate, the striking face 36 includes a first point (P1) located laterally toe-ward from the face center (0,0) along the Z-axis by a distance D1 between 25 mm and 35 mm and located vertically below the Z-axis in the Y-axis direction by a distance between 5 mm and 15 mm. The first point P1 is associated with a first loft and a first roll radius. The striking face 34 also includes a second point (P2) located laterally heel-ward from the face center (0,0) along the Z-axis by the distance D1 and located vertically below the Z-axis in the Y-axis direction by the distance D2. The second point P2 is associated with a second loft that is less than the first loft by at least 1 degree, and preferably at least 2 degrees. The second point is also associated with a second roll radius that is less than the first roll radius by at least 5 in, preferably at least 7 in, and more preferably at least 10 in.

[0052] Following the example above, the striking face 36 may further include a third point located laterally toe-ward from the face center (0,0) along the Z-axis by a distance D3 between 25 mm and 35 mm. The third point is associated with a third loft that is greater than the first loft. The third point is also associated with a third roll radius that is less than the first roll radius and greater than the second roll radius. The striking face 36 may further include a fourth point P4 located laterally heel-ward from the face center (0,0) along the Z-axis by the distance D3. The fourth point is associated with a fourth loft that is within 0.2 degrees or preferably within 0.1 degrees of the third loft. The fourth point is also associated with a fourth roll radius that is within 0.5 in. or preferably within 0.2 in. of the third roll radius.

[0053] In some examples, the face center (0,0) is associated with a first face angle and a fifth roll radius. In such an example, the striking face 36 further includes a fifth point P5 located vertically above the center (0,0) along the Y-axis by a distance D5 between 5 mm and 20 mm. The fifth point P5 is associated with a second face angle that is within 0.2 degrees or preferably within 0.1 degree of the first face angle. The fifth point P5 is also associated with a sixth roll radius that is within 0.2 in. or preferably within 0.1 in. of the fifth roll radius. In some examples, a roll radius for at least 90%, preferably at least 95%, and more preferably greater than 95% of locations occupying the striking face above the virtual Z-axis is within 0.2 in. or preferably within 0.1 in. of the fifth roll radius.

[0054] The striking face 36 shown and described in FIGS. 4A-D may provide various benefits over a standard striking face. For example, the striking face 36 may provide improved shot dispersion when compared with a standard striking face. Furthermore, for impacts below the Z-axis, the striking face 36 will impart less fade or slice spin (assuming a right-handed player), which results in straighter shots. Such a characteristic may prevent a “slice” that commonly occurs with a low-heel impact. Furthermore, for impacts above the Z-axis, the striking face 36 may launch a golf ball left of a target line. As such, the striking face 36 may be beneficial to a particular subset of players who may tend to slice the golf ball, which is relatively common in mid-to-high handicap players. Simulated test data of the striking face 36 is further described with respect to FIG. 12 below.

[0055] Furthermore, the striking face 36 may provide various benefits over other striking faces that attempt to reduce gear effect. For example, the striking face 36 described herein minimizes complex variability to regions of greatest impact for a subset of players. This provides a unique advantage over other striking faces that attempt to minimize gear effect. For example, the striking face 36 may minimize complex variability, reducing overall precision required in polishing, and / or reducing cost in forming such a striking face 36. As such, the striking face 36 described herein is effective to not overburden manufacturing resulting in a striking face 36 that effectively reduces gear effect.

[0056] FIGS. 5A-D illustrate coordinate maps of an example striking face 38 of a golf club head. As may be apparent from the figures, the striking face 38 shown in FIGS. 5A-D may be a combination of the striking face 34 shown in FIGS. 3A-D and the striking face 26 shown in FIGS. 4A-D. The coordinate maps depict the striking face 38 tilted relative to the plane defined by the Y and Z axes such that the origin (i.e., 0,0 on the coordinate map) has a loft of 0 and a face angle of 0. It is noted that the specific values shown on the coordinate maps are not limiting and merely show exemplary values for the inventive striking faces described herein. The specific values shown may also vary due to mathematical rounding and the relative values shown on the coordinate maps are not limiting and are merely exemplary. Specific values and ranges thereof will be described further herein below.

[0057] In some examples and following the second order polynomial surface equation described above, the striking face 38 may be defined using separate equations to represent the top half (y>0) and the bottom half (y≤0) of the striking face 38. As such, the striking face 38 may be defined by a piecewise equation as follows:x⁡(y, z)={p2⁢z2+p6⁢y2+p7⁢t⁢y2⁢zy>0p2⁢z2+p6⁢y2+p7⁢b⁢y2⁢zy≤0⁢ andp2<0,p6<0,p7⁢t<0,p7⁢b>0

[0058] As shown in FIG. 5B, the striking face 36 includes a bottom half (y≤0) and a top half (y>0) that have varying roll. For example, on the top half (y>0) of the striking face 38, the roll radius on the heel side (z<0) is greater than the roll radius on the toe side (z>0). Conversely, the bottom half (y≤0) of the striking face includes the roll radius on the toe side (z>0) is greater than the roll radius on the heel side (z<0). In some examples, the roll radius of the top half (y>0) and the bottom half (y≤0) of the striking face may vary between approximately 5 in. and 24 in, or preferably between approximately 6 in. and 22 in. Additionally, the roll radius along the Z-axis is substantially constant. In the provided example, the roll radius along the Z-axis may be approximately 10 in. However, it is to be understood that the specific values may vary.

[0059] As shown in FIG. 5C, the top half (y>0) of the striking face 38 includes a loft on the toe side (z>0) that is greater than the loft of the heel side (z<0) for the same value of y. Conversely, the bottom half (y≤0) of the striking face 38 includes a loft on the heel side (z<0) that is less than the loft of the toe side (z>0) for the same value of y. Additionally, the loft of the striking face 38 along the Z-axis is substantially equal to the loft at the origin (0,0). In some examples, the average added loft of the striking face 36 of the golf club head is 0.

[0060] Furthermore, and as shown in FIG. 5D, the top half (y>0) of the striking face 38 includes an open face angle, while the bottom half (y≤0) of the striking face 38 includes a closed face angle. In such an example, the average face angle of the entire striking face 38 is neutral.

[0061] To illustrate, the striking face 38 includes a first point (P1) located laterally toe-ward from the face center (0,0) along the Z-axis by a distance D1 between 25 mm and 35 mm and located vertically above the Z-axis in the Y-axis direction by a distance between 5 mm and 15 mm. The first point P1 is associated with a first loft and a first roll radius. The striking face 38 also includes a second point (P2) located laterally heel-ward from the face center (0,0) along the Z-axis by the distance D1 and located vertically above the Z-axis in the Y-axis direction by the distance D2. The second point P2 is associated with a second loft that is less than the first loft by at least 1 degree, and preferably at least 2 degrees. The second point P2 is also associated with a second roll radius that is greater than the first roll radius by at least 5 in, preferably at least 7 in, and more preferably at least 10 in.

[0062] Following the example above, the striking face 38 may further include a third point P3 located laterally toe-ward from the face center (0,0) along the Z-axis by a distance D1 between 25 mm and 35 mm and located vertically below the Z-axis in the Y-axis direction by a distance between 5 mm and 15 mm. The third point P3 is associated with a third loft that is within 6 degrees, preferably within 5 degrees, and more preferably within 3 degrees of the second loft. In some examples, the third point P3 is associated with a relative absolute loft (i.e., the absolute value of loft relative to a datum such as face center) that is within 0.5 degrees, preferably within 0.2 degrees, and more preferably within 0.1 degree of a relative absolute loft associated with the second point P2 (where each point on the face is relative to the same datum such as the face center). The third point P3 is also associated with a third roll radius that is within 1.5 in., preferably within 1.0 in, or preferably within 0.5 in. of the second roll radius. The striking face 34 also includes a fourth point P4 located laterally heel-ward from the face center (0,0) along the Z-axis by the distance D1 and located vertically below the Z-axis in the Y-axis direction by the distance D2. Similarly, the fourth point P4 is associated with a fourth loft that is within 6 degrees, preferably within 5 degrees, and more preferably within 3 degrees of the first loft. In some examples, the fourth point P4 is associated with a relative absolute loft (i.e., the absolute value of loft relative to a datum such as face center) that is within 0.5 degrees, preferably within 0.2 degrees, and more preferably within 0.1 degree of a relative absolute loft associated with the first point P1 (where each point on the face is relative to the same datum such as the face center). The fourth point is also associated with a fourth roll radius that is within 1.5 in., preferably within 1.0 in, or preferably within 0.5 in. of the first roll radius.

[0063] In some examples, the face center (0,0) is associated with a first face angle and a fifth roll radius. In such an example, the striking face 36 further includes a fifth point P5 located vertically above the center (0,0) along the Y-axis by a distance D5 between 5 mm and 20 mm. The fifth point P5 is associated with a second face angle that is within 0.2 degrees or preferably within 0.1 degree of the first face angle. The fifth point P5 is also associated with a sixth roll radius that is within 0.2 in. or preferably within 0.1 in. of the fifth roll radius. In some examples, a roll radius for at least 90%, preferably at least 95%, and more preferably greater than 95% of locations occupying the striking face above the virtual Z-axis is within 0.2 in. or preferably within 0.1 in. of the fifth roll radius.

[0064] The striking face 38 shown and described in FIGS. 5A-D may provide various benefits over a standard striking face. For example, the striking face 38 may provide improved shot dispersion when compared with a standard striking face. In some examples, for impacts above the Z-axis, the striking face 38 will impart less draw spin (assuming a right-handed player), which results in straighter shots. Furthermore, for impacts below the Z-axis, the striking face 38 will impart less fade or slice spin (assuming a right-handed player), which results in straighter shots. Simulated test data of the striking face 36 is further described with respect to FIG. 12 below.

[0065] Furthermore, the striking face 38 may provide various benefits over other striking faces that attempt to reduce gear effect. For example, the striking face 38 described herein blends two advantageous striking face designs, while maintaining a substantially neutral central region of the striking face 38. As such, the striking face 38 provides benefit for off center shots but maintains maximal carry and accuracy for impacts that occur proximate the face center.

[0066] FIGS. 6A-D illustrate coordinate maps of an example striking face 40 of a golf club head. The coordinate maps depict the striking face 40 tilted relative to the plane defined by the Y and Z axes such that the origin (i.e., 0,0 on the coordinate map) has a loft of 0 and a face angle of 0. It is noted that the specific values shown on the coordinate maps are not limiting and merely show exemplary values for the inventive striking faces described herein. The specific values shown may also vary due to mathematical rounding and the relative values shown on the coordinate maps are not limiting and are merely exemplary. Specific values and ranges thereof will be described further herein below.

[0067] In some examples and following the second order polynomial surface equation described above, the striking face 40 may be defined using separate equations to represent a toe half (z>0) and a heel half (z≤0) of the striking face 40. As such, the striking face 40 may be defined by a piecewise equation as follows:x⁡(y, z)={p2⁢z2+p5⁢yz2+p6⁢y2z>0p2⁢z2+p6⁢y2z≤0⁢ andp2<0,p6<0,p5<0

[0068] As shown in FIG. 6A, the striking face 40 includes a toe half (z>0) that has varying bulge. For example, on the toe half (z>0) of the striking face 40, the bulge radius on the bottom half (y≤0) is greater than the bulge radius top side (y>0). In some examples, the bulge radius of the toe half (z>0) of the striking face may vary between approximately 7 in. and 26 in, or preferably between approximately 8 in. and 24 in. Additionally, the bulge radius along the Y-axis is substantially constant. In the provided example, the bulge radius along the Z-axis may be approximately 13 in. However, it is to be understood that the specific values may vary. Additionally, in some examples, the bulge radius of the heel half (z≤0) of the club face is also substantially constant.

[0069] As shown in FIG. 6C, the toe half (z>0) of the striking face 40 includes a loft on the toe side (z>0) that is greater than the loft of the heel half (z≤0) for the same value of y As such, the loft of the striking face 40 varies along the Z-axis. Furthermore, the average added loft of the striking face 40 of the golf club head is greater than 0.

[0070] Furthermore, and as shown in FIG. 6D, the toe half (z>0) of the striking face 40 includes a face angle on the top half (y>0) that is more open than a face angle on the bottom half (y≤0) for the same value of z. In such an example, the average face angle of the entire striking face 40 is neutral.

[0071] The striking face 40 shown and described in FIGS. 6A-D may provide various benefits over a standard striking face. For example, the striking face 64 may provide improved shot dispersion when compared with a standard striking face. Furthermore, for impacts toe-ward of the Y-axis, the striking face 40 will impart less draw spin (assuming a right-handed player), which results in straighter shots. Such a characteristic may prevent a “snap hook” that commonly occurs with a high-toe impact. Furthermore, since the striking face 40 includes an average added loft greater than 0, the striking face 40 may launch the ball higher than a standard face. As such, the striking face 40 may be beneficial to a particular subset of players who may tend to hook the golf ball and / or for players that tend to hit the ball undesirably low. Simulated test data of the striking face 40 is further described with respect to FIG. 12 below.

[0072] Furthermore, the striking face 40 may provide various benefits over other striking faces that attempt to reduce gear effect. For example, the striking face 40 described herein minimizes complex variability to regions of greatest impact for a subset of players. This provides a unique advantage over other striking faces that attempt to minimize gear effect. For example, the striking face 40 may minimize complex variability, reducing overall precision required in polishing, and / or reducing cost in forming such a striking face 40. As such, the striking face 40 described herein is effective to not overburden manufacturing resulting in a striking face 40 that effectively reduces gear effect.

[0073] FIGS. 7A-D illustrate coordinate maps of an example striking face 42 of a golf club head. The coordinate maps depict the striking face 42 tilted relative to the plane defined by the Y and Z axes such that the origin (i.e., 0,0 on the coordinate map) has a loft of 0 and a face angle of 0. It is noted that the specific values shown on the coordinate maps are not limiting and merely show exemplary values for the inventive striking faces described herein. The specific values shown may also vary due to mathematical rounding and the relative values shown on the coordinate maps are not limiting and are merely exemplary. Specific values and ranges thereof will be described further herein below.

[0074] In some examples and following the second order polynomial surface equation described above, the striking face 42 may be defined using separate equations to represent a toe half (z>0) and a heel half (z≤0) of the striking face 42. As such, the striking face 42 may be defined by a piecewise equation as follows:x⁡(y, z)={p2⁢z2+p6⁢y2z>0p2⁢z2+p5⁢yz2+p6⁢y2z≤0⁢ andp2<0,p6<0,p5>0

[0075] As shown in FIG. 7B, the striking face 42 includes a toe half (z>0) that has substantially constant bulge and roll. Furthermore, the heel half (z≤0) of the striking face 42, the bulge radius of the bottom half (y≤0) is less than the bulge radius of the top half (y>0). In some examples, the bulge radius of the heel half (z≤0) of the striking face may vary between approximately 7 in. and 26 in, or preferably between approximately 8 in. and 24 in. Additionally, the bulge radius along the Y-axis is substantially constant. In the provided example, the bulge radius along the Z-axis may be approximately 13 in. However, it is to be understood that the specific values may vary.

[0076] As shown in FIG. 7C, the heel half (z≤0) of the striking face 42 includes a loft on the toe side (z>0) that is greater than the loft of the heel half (z≤0) for the same value of y. As such, the loft of the striking face 42 varies along the Z-axis. Furthermore, the average added loft of the striking face 42 of the golf club head is less than 0.

[0077] Furthermore, and as shown in FIG. 7D, the heel half (z≤0) of the striking face 42 includes a face angle on the top half (y>0) that is less closed than a face angle on the bottom half (y≤0) for the same value of z. In such an example, the average face angle of the entire striking face 42 is neutral.

[0078] The striking face 42 shown and described in FIGS. 7A-D may provide various benefits over a standard striking face. For example, the striking face 42 may provide improved shot dispersion when compared with a standard striking face. Furthermore, for impacts heel-ward of the Y-axis, the striking face 42 will impart less fade spin (assuming a right-handed player), which results in straighter shots. Such a characteristic may prevent a “slice” that commonly occurs with a low-heel impact. Simulated test data of the striking face 40 is further described with respect to FIG. 12 below.

[0079] Furthermore, the striking face 42 may provide various benefits over other striking faces that attempt to reduce gear effect. For example, the striking face 42 described herein minimizes complex variability to regions of greatest impact for a subset of players. This provides a unique advantage over other striking faces that attempt to minimize gear effect. For example, the striking face 42 may minimize complex variability, reducing overall precision required in polishing, and / or reducing cost in forming such a striking face 42. As such, the striking face 42 described herein is effective to not overburden manufacturing resulting in a striking face 42 that effectively reduces gear effect.

[0080] FIGS. 8A-D illustrate coordinate maps of an example striking face 44 of a golf club head. As may be apparent from the figures, the striking face 44 shown in FIGS. 8A-D may be a combination of the striking face 40 shown in FIGS. 6A-D and the striking face 42 shown in FIGS. 7A-D. The coordinate maps depict the striking face 44 tilted relative to the plane defined by the Y and Z axes such that the origin (i.e., 0,0 on the coordinate map) has a loft of 0 and a face angle of 0. It is noted that the specific values shown on the coordinate maps are not limiting and merely show exemplary values for the inventive striking faces described herein. The specific values shown may also vary due to mathematical rounding and the relative values shown on the coordinate maps are not limiting and are merely exemplary. Specific values and ranges thereof will be described further herein below.

[0081] In some examples and following the second order polynomial surface equation described above, the striking face 44 may be defined using separate equations to represent a toe half (z>0) and a heel half (z≤0) of the striking face 44. As such, the striking face 44 may be defined by a piecewise equation as follows:x⁡(y, z)={p2⁢z2+p5⁢t⁢yz2+p6⁢y2z>0p2⁢z2+p5⁢h⁢yz2+p6⁢y2z≤0⁢ andp2<0,p6<0,p5⁢t>0,p5⁢h<0

[0082] As shown in FIG. 8A, the striking face 44 includes a toe half (z>0) and a heel half (z≤0) that have varying bulge. For example, the toe half (z>0) of the striking face 44 includes a bulge radius on the bottom half (y≤0) is greater than the bulge radius top side (y>0). Additionally, the heel half (z≤0) of the striking face includes a bulge radius of the bottom half (y≤0) that is less than the bulge radius of the top half (y>0). In some examples, the bulge radius of the toe half (z>0) and the heel half (z≤0) of the striking face 44 may vary between approximately 7 in. and 26 in, or preferably between approximately 8 in. and 24 in. Additionally, the bulge radius along the Y-axis may be substantially constant.

[0083] As shown in FIG. 8C, the striking face 44 includes a loft on the toe side (z>0) that is greater than the loft of the heel half (z≤0) for the same value of y. In such an example, the loft of the striking face 44 varies along the Z-axis. Furthermore, the average added loft of the striking face 44 of the golf club head is 0.

[0084] Furthermore, and as shown in FIG. 8D, the toe half (z>0) of the striking face 44 includes a face angle on the top half (y>0) that is more open than a face angle on the bottom half (y≤0) for the same value of z. Similarly, the heel half (z≤0) of the striking face 44 includes a face angle on the top half (y>0) that is less closed than a face angle on the bottom half (y≤0) for the same value of z. In such an example, the average face angle of the entire striking face 44 is neutral.

[0085] The striking face 44 shown and described in FIGS. 8A-D may provide various benefits over a standard striking face. For example, the striking face 44 may provide improved shot dispersion when compared with a standard striking face. In some examples, for toe-side impacts, the striking face 44 will impart less draw spin (assuming a right-handed player), which results in straighter shots. Furthermore, for heel-side impacts, the striking face 44 will impart less fade or slice spin (assuming a right-handed player), which results in straighter shots. Simulated test data of the striking face 44 is further described with respect to FIG. 12 below.

[0086] Furthermore, the striking face 44 may provide various benefits over other striking faces that attempt to reduce gear effect. For example, the striking face 44 described herein blends two advantageous striking face designs, while maintaining a substantially neutral central region of the striking face 44. As such, the striking face 44 provides benefit for off center shots but maintains maximal carry and accuracy for impacts that occur proximate the face center.

[0087] According to another example, FIGS. 9 and 10 depict a golf club head 10 that may be substantially the same as the golf club head shown and described with respect to FIGS. 1 and 2. However, the golf club head 10 includes a striking face 46 having a striking face 46 with another configuration. The striking face 46 of the golf club head 10 includes substantially constant bulge and roll curvature.

[0088] In some examples, the golf club head 10 includes a virtual vertical plane 48 passing through the face center 32. Referring now to FIG. 10, the golf club head 10 includes a virtual striking face plane 50 that extends tangent to the face center 32. The golf club head 10 also includes an axis of rotation 52 passing through the face center 32 and extending perpendicular to the virtual striking face plane 50. The golf club head 10 further includes a virtual transverse plane 54 coplanar with the axis of rotation 52 and extending in a heel-to-toe direction.

[0089] The golf club head 10 further includes a virtual bulge plane 56 that is coplanar with the axis of rotation 52 and defined such that all points on the striking face 46 and in the virtual bulge plane 56 have substantially the same bulge radius. As shown in FIG. 9, the virtual bulge plane is rotationally offset by 0 of at least 18 degrees counterclockwise about the axis of rotation from the virtual transverse plane 54. In some examples, the virtual bulge plane 56 is rotationally offset counterclockwise from the virtual transverse plane 54 by between 16 and 40 degrees, or preferably between 18 and 30 degrees.

[0090] Similarly, the golf club head 10 includes a virtual roll plane 58 that is coplanar with the axis of rotation 52 and is defined such that all points on the striking face 46 and in the virtual roll plane 58 have substantially the same roll radius. As shown in FIG. 9, the virtual roll plane 58 is rotationally offset by 0 of at least 18 degrees counterclockwise about the axis of rotation 52 from the virtual vertical plane 48. In some examples, the virtual roll plane 58 is rotationally offset counterclockwise from the virtual vertical plane 48 by between 16 and 40 degrees, or preferably between 18 and 30 degrees.

[0091] To illustrate, and as shown in FIGS. 11A-11D, the striking face 46 includes a first point P1 located laterally toe-ward from the face center (0,0) along the Z-axis by a distance between 25 mm and 35 mm. The first point P1 is associated with a first loft, a first bulge radius, and a first roll radius. The striking face 46 further includes a second point P2 that is located laterally heel-ward from the face center 32 along the Z-axis by the distance D1. The second point P2 is associated with a second loft that is less than the first loft by at least 0.5 degrees, or preferably by at least 1 degree, or more preferably by at least 1.5 degrees. Furthermore, the second point P2 is associated with a second bulge radius that is within 0.2 in., or preferably within 0.1 in. of the first bulge radius. The second point is also associated with a second roll radius that is within 0.2 in., or preferably within 0.1 in. of the first roll radius.

[0092] Furthermore, the face center (0,0) is associated with a third bulge radius that is within 0.2 in., or preferably within 0.1 in. of the first bulge radius. The face center (0,0) is also associated with a third roll radius that is within 0.2 in., or preferably within 0.1 in. of the first roll radius. In some examples, a bulge radius for at least 90%, or preferably at least 92%, or more preferably at least 95% of locations occupying the striking face 46 is within 0.2 in, or preferably within 0.1 in. of the first bulge radius. Similarly, a roll radius for at least 90%, or preferably at least 92%, or more preferably at least 95% of locations occupying the striking face 46 is within 0.2 in, or preferably within 0.1 in. of the first roll radius.

[0093] The striking face 46 shown and described in FIGS. 9-11 may provide various benefits over a standard striking face. For example, the striking face 46 may provide improved shot dispersion when compared with a standard striking face. In some examples, for impacts above the Z-axis, the striking face 46 will impart less draw spin (assuming a right-handed player), which results in straighter shots. Furthermore, for impacts below the Z-axis, the striking face 46 will impart less fade or slice spin (assuming a right-handed player), which results in straighter shots. Simulated test data of the striking face 46 is further described with respect to FIG. 12 below.

[0094] Furthermore, the striking face 46 may provide various benefits over other striking faces that attempt to reduce gear effect. For example, the striking face 46 described herein blends two advantageous striking face designs, while maintaining a substantially neutral central region of the striking face 46. As such, the striking face 46 provides benefit for off center shots but maintains maximal carry and accuracy for impacts that occur proximate the face center.

[0095] FIG. 12 depicts simulated test data for the striking faces described herein. The first column depicts the difference in mean distance (in yards), the second column depicts the difference in standard deviation distance (in yards), and the third column depicts the difference in standard deviation distance (in yards). The data shown in FIG. 12 is compared to simulated test data of a standard striking face having substantially constant bulge and roll curvature. As shown in FIG. 12, each of the striking faces provide increased distance, while reducing offline shots.

[0096] In the foregoing discussion, the present invention has been described with reference to specific exemplary aspects thereof. However, it will be evident that various modifications and changes may be made to these exemplary aspects without departing from the broader spirit and scope of the invention. Accordingly, the foregoing discussion and the accompanying drawings are to be regarded as merely illustrative of the present invention rather than as limiting its scope in any manner.

Examples

Embodiment Construction

[0025]In some aspects of the present disclosure, referring to FIG. 1, a golf club head 10 is shown. The golf club head 10 includes a crown portion 12 (or top portion) and a sole portion 14 opposite the crown 12. The golf club head 10 further includes a toe portion 16 and a heel portion 18 opposite the toe portion 16. The golf club head 10 also includes a striking face 20 and a hosel 22 that extends from the heel portion 18. The hosel 22 includes an internal hosel bore 24 configured to receive a shaft (not shown) therein. The internal hosel bore 24 defines a central axis, i.e., a hosel axis 26.

[0026]The striking face 20 is generally planar (or quasi-planar), but includes curvature of relatively high radius (i.e., no less than 6 in). Furthermore, the striking face 20 includes bulge and roll curvature. Bulge refers to the curvature of the striking face 20 in a generally heel-to-toe direction, while roll refers to the curvature of the striking face in a generally top-to-bottom direction...

[0001] This application is a non-provisional of Provisional Application No. 63 / 664,918, filed on Jun. 27, 2024, the contents of which is incorporated by reference herein in its entirety.BACKGROUND

[0002] The performance of golf clubs is evaluated on the basis of many factors, which vary dependent on the type of club. When evaluating wood-type golf clubs, golfers tend to value distance and accuracy as the most important factors.

[0003] Often, golf clubs may be designed to perform well under ideal conditions including for impacts at an ideal location on the striking face. However, evaluating performance under ideal conditions alone may not result in a golf club that performs well for a particular golfer overall. For example, golf clubs, particularly wood-type clubs, are often designed such that impacts at or near a face center lead to most effective overall results. However, such a principle may not be realistic, particularly for some classes of golfer.

[0004] Furthermore, when a golf ball is struck off-center, the clubface tends to impart spin on a golf ball in a direction opposite to the direction of the off-center impact on the clubface. Such an effect is commonly referred to as “gear effect”. Gear effect occurs due to the curvature of the clubface and the resulting interaction between the clubface and the golf ball during impact.

[0005] When a golf ball is struck off-center on the club face, the clubface imparts both linear and rotational forces on the ball. If the impact occurs towards the toe-side of an ideal impact location of the clubface, the golf ball tends to rotate counterclockwise (assuming a right-handed player and when viewing the club face and golf ball in a top-down view). If the impact occurs towards the heel-side of an ideal impact location of the clubface, the golf ball tends to rotate clockwise.

[0006] The club face of a wood-type golf club head is often designed with bulge and roll to help minimize adverse effects of off-center hits. Incorporating curvature on the club face enables deviation in trajectory to counteract the spin-induced bias generated by off-center hits. Bulge refers to the curvature in a heel-to-toe direction, while roll refers to the curvature in a crown-to-sole direction. Bulge and roll can help reduce the severity of gear effect for off-center impacts. However, gear effect still plays a significant role in shaping the trajectory of shots, especially with wood-type golf club heads that have a larger club face, such as drivers.SUMMARY

[0007] An object, therefore, of the present disclosure is to provide a golf club head that includes a club face that is designed to maximize distance and accuracy by reducing gear effect for off-center impacts.

[0008] In one aspect of the present disclosure, a golf club head includes a volume greater than 400 cubic centimeters, a crown portion, a sole portion opposite the crown portion, a toe portion, a heel portion portion opposite the toe portion, and a striking face. The striking face includes a face center, a first point located laterally toe-ward from the face center by a first distance D1 between 25 mm and 35 mm, the first point associated with a first loft, a first bulge radius, and a first roll radius, and a second point located laterally heel-ward from the face center by the first distance D1, the second point associated with a second loft that is less than the first loft by at least 0.5 degrees, a second bulge radius that is within 0.2 in of the first bulge radius, and a second roll radius that is within 0.2 in of the first roll radius.

[0009] In another aspect of the present disclosure, a golf club head, when oriented in a reference position relative to a virtual ground plane includes a volume greater than 400 cubic centimeters, a crown portion, a sole portion opposite the crown portion, a toe portion, a heel portion opposite the toe portion, and a striking face. The striking face includes a face center, such that a virtual horizontal plane passes through the face center, a first point located laterally toe-ward from the face center by a distance D1 between 25 mm and 35 mm and located vertically above the virtual horizontal plane by a distance D2 between 5 mm and 15 mm, the first point associated with a first loft and a first roll radius, and a second point located laterally heel-ward from the face center by the distance D1 and located vertically above the virtual horizontal plane by the distance D2, the second point associated with a second loft that is less than the first loft by at least 1 degree and a second roll radius that is greater than the first roll radius by at least 5 in.

[0010] In another aspect of the present disclosure, a golf club head, when oriented in a reference position relative to a virtual ground plane includes a volume greater than 400 cubic centimeters, a crown portion, a sole portion opposite the crown portion, a toe portion, a heel portion opposite the toe portion, and a striking face. The striking face includes a face center, such that a virtual horizontal plane passes through the face, a first point located laterally toe-ward from the face center by a distance D1 between 25 mm and 35 mm and located vertically below the virtual horizontal plane by a distance D2 between 5 mm and 15 mm, the first point associated with a first loft and a first roll radius, and a second point located laterally heel-ward from the face center by the distance D1 and located vertically below the virtual horizontal plane by the distance D2, the second point associated with a second loft that is less than the first loft by at least 1 degree and a second roll radius that is that is greater than the first roll radius by at least 5 in.

[0011] These and other features and advantages of the golf club heads, their implementations, and the methods of manufacture thereof according to the various aspects of the present disclosure will become more apparent upon consideration of the following description, drawings, and appended claims. The description and drawings described below are for illustrative purposes only and are not intended to limit the scope of the present invention in any manner.BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The drawings described below are for illustrative purposes only and are not intended to limit the scope of the present invention in any way. Exemplary implementations will now be described with reference to the accompanying drawings, wherein:

[0013] FIG. 1 shows a front elevation view of an exemplary golf club head in accordance with one or more aspects of the present disclosure.

[0014] FIG. 2 illustrates a perspective view of an exemplary golf club head with an example coordinate system in accordance with one or more aspects of the present disclosure.

[0015] FIGS. 3A-D illustrate coordinate maps of an example striking face of a golf club head in accordance with one or more aspects of the present disclosure.

[0016] FIGS. 4A-D illustrate coordinate maps of another example striking face of a golf club head in accordance with one or more aspects of the present disclosure.

[0017] FIGS. 5A-D illustrate coordinate maps of a further example striking face of a golf club head in accordance with one or more aspects of the present disclosure.

[0018] FIGS. 6A-D illustrate coordinate maps of a further example striking face of a golf club head in accordance with one or more aspects of the present disclosure.

[0019] FIGS. 7A-D illustrate coordinate maps of a further example striking face of a golf club head in accordance with one or more aspects of the present disclosure.

[0020] FIG. 8A-D illustrate coordinate maps of a further example striking face of a golf club head in accordance with one or more aspects of the present disclosure.

[0021] FIG. 9 shows a front elevation view of an exemplary golf club head in accordance with one or more aspects of the present disclosure.

[0022] FIG. 10 shows a heel side view of an exemplary golf club head in accordance with one or more aspects of the present disclosure.

[0023] FIGS. 11A-D illustrate coordinate maps of an example striking face of a golf club head in accordance with one or more aspects of the present disclosure.

[0024] FIG. 12 depicts simulated test data for various striking faces described in accordance with one or more aspects of the present disclosure.DETAILED DESCRIPTION

[0025] In some aspects of the present disclosure, referring to FIG. 1, a golf club head 10 is shown. The golf club head 10 includes a crown portion 12 (or top portion) and a sole portion 14 opposite the crown 12. The golf club head 10 further includes a toe portion 16 and a heel portion 18 opposite the toe portion 16. The golf club head 10 also includes a striking face 20 and a hosel 22 that extends from the heel portion 18. The hosel 22 includes an internal hosel bore 24 configured to receive a shaft (not shown) therein. The internal hosel bore 24 defines a central axis, i.e., a hosel axis 26.

[0026] The striking face 20 is generally planar (or quasi-planar), but includes curvature of relatively high radius (i.e., no less than 6 in). Furthermore, the striking face 20 includes bulge and roll curvature. Bulge refers to the curvature of the striking face 20 in a generally heel-to-toe direction, while roll refers to the curvature of the striking face in a generally top-to-bottom direction. In some examples, the bulge and / or roll of the striking face may be of substantially constant radius across the striking face 20. However, in other examples, the bulge and / or roll may vary in radius across the striking face 20 in a vertical direction and / or a horizontal direction.

[0027] The striking face 20 is delimited by a striking face periphery 28. The striking face periphery 28 is defined by the loci of points circumscribing the quasi-planar region that defines the striking face 20, as described above. In some examples, the striking face periphery 28 may be readily ascertainable, such as by the presence of abrupt change in contour forming an angled peripheral edge. However, in other examples, the transition from the striking face 20 to a main body of the golf club head 10 may be less visually discernible. In such examples, the striking face periphery 28 is understood to be the loci of point circumscribing the quasi-planar striking face 20 where transition occurs from a high radius of curvature to a low radius of curvature (i.e., less than 4 in.).

[0028] The golf club head 10 shown and described herein may include various configurations of different striking faces that minimize and / or reduce the gear effect for golf ball impact across the striking face and / or for golf ball impacts on a specific region of the striking face 20. Such configurations may: improve dispersion of shots compared to a standard striking face and / or improve carry distance of shots compared to a standard striking face. These and other improvements will be described further herein below with respect to the various configurations described herein.

[0029] The golf club head 10 is shown in a reference position. As used herein, “reference position”, refers to a position of the golf club head 10 where the hosel axis 26 is oriented at a lie angle of about 60° (+ / −5° depending on the particular configuration of the hosel) with respect to a virtual ground plane 30, and lies in a virtual vertical hosel plane 27 (shown in FIG. 1), which contains an imaginary horizontal line generally parallel to the striking face 20. Unless state otherwise, attributes of the golf club head 10 described herein are presumed to apply to the golf club head 10 as oriented in a reference position.

[0030] The striking face 20 of the golf club head 10 includes a face center 32. For all purposes herein, “face center” (e.g., face center 32) refers to a point on a striking face of a golf club head that is simultaneously: (a) laterally equidistant from the heel-side and toe-side of the periphery of the striking face 20; and (b) vertically equidistant from the top-side and the sole-side of the periphery of the striking face 20 of the golf club head 20.

[0031] From a practical standpoint, face center (e.g., face center 32, as shown in FIG. 1) may be determined in accordance with the United States Golf Association's Procedure for Measuring the Flexibility of a Golf Clubhead (Revision 2.0, Mar. 25, 2005) available from the USGA. Specifically, a standard template is used that has a coordinate system with a heel-toe axis orthogonal to a top-bottom axis. An aperture is disposed at the origin of the coordinate system, with the axes being graduated into evenly spaced increments. The template may be made of a flexible material, e.g., a transparent polymer. The location of the face center, e.g. face center 32, is determined by initially applying the template to the striking face 20 so that the aperture is approximately in the middle of the striking face 20 and the heel-toe axis is generally horizontal. The template is then translated in the heel-toe direction along the striking face 20 until the heel and toe measurements along the axis at opposite points on the striking face perimeter of the striking face 20 proximate respective ones of the toe and heel portions 16 and 18 have the same absolute value. Once the template is centered with respect to the striking face 20 in the heel-toe direction, the template is translated into the top-bottom direction along the striking face 20 until the measurements along the axis at opposite points on the striking face perimeter of the striking face 20 proximate respective ones of the top and bottom portions 12 and 14 have the same absolute value. The above sequence is repeated until the absolute value of the heel measurement along the axis is equal to that of the toe measurement and the absolute value of the bottom measurement along axis is equal to that of the top measurement. A point is then marked on the striking face 20 through the aperture to designate the face center 32.

[0032] As mentioned previously, the golf club head 10 is a wood-type club head. Preferably, the golf club head 10 is a driver-type club head (e.g., configured to impact a golf ball off a tee and / or has a loft that is less than 15 degrees). Accordingly, the golf club head 10 preferably has a volume no less than 390 cubic centimeters (cc), more preferably between about 410 cc and 470 cc, even more preferably between about 440 cc and 465 cc. Additionally, or alternatively, the golf club head 10 has a head mass no less than 170 g, more preferably no less than 185 g, and even more preferably within the range of about 185 g to 210 g. In some examples, the golf club head 10 may be a miniature-type driver having a volume between about 250 cc and 350 cc and having a mass between about 175 g to 250 g. Furthermore, in some examples, the golf club head 10 may include fairway and / or hybrid type golf club heads. For example, the golf club head 10 may have a volume between about 120 cc and 220 cc for fairway-type golf club heads and between about 75 cc and 150 cc for hybrid-type golf club heads. Additionally, the golf club head 10 may have a mass between about 190 g to 250 g for fairway-type golf club heads and between about 200 g to 275 g for hybrid-type golf club heads.

[0033] Further shown in FIG. 1 are a virtual Y-axis and a virtual Z-axis. The origin of the virtual Y-axis and the virtual Z-axis coincides with the face center 32. With the golf club head 10 in the reference position, the Y-axis extends in a sole to crown direction and tangent to the face center 32. A positive Y-axis corresponds with a sole 14 to crown 12 direction, thus positive y values correspond with locations crown-ward of the face center 32 and negative y values correspond with locations sole-ward of the face center 32. The Z-axis extends in a direction parallel to the virtual ground plane 30 and tangent the face center 32. Furthermore, a positive Z-axis direction corresponds with a heel to toe direction such that locations toe-ward of the face center 32 have positive z values and locations heel-ward of the face center 32 have negative z values.

[0034] FIG. 2 illustrates a perspective view of the golf club head 10 having a coordinate system, as described previously. Further shown in FIG. 2 is a virtual X-axis that is normal to the striking face 20 at the face center 32 (i.e., the origin of the coordinate system). A positive X-axis direction corresponds with a forward direction such that locations forward of the origin, i.e. the face center 32, have positive x values and locations rearward of the face center 32 have negative x values. In some examples, the striking face 20 surface x(y, z) may be represented as a second order polynomial surface with 9 parameters (p0, p1, . . . , p8):x⁡(y,z)=p0+p1⁢z+p2⁢z2+p3⁢y+p4⁢y⁢z+p5⁢y⁢z2+p6⁢y2+p7⁢y2⁢z+p8⁢y2⁢z2

[0035] Using various ranges for the parameters p, the second order polynomial surface equation describes a variety of clubface curvatures. For example, setting p2<0 and p6<0 and setting the remaining parameters to zero creatures a standard striking face curvature that includes substantially constant bulge and roll, where p2 controls the bulge and p6 controls the roll. As such, the polynomial surface equation may be used to characterize various striking face 20 curvatures, as described further herein below. It should be noted that when parameters are omitted from the polynomial surface equation, such parameters are assumed to be equal to zero. In some examples, the golf club head 10 includes an overall or effective club head loft between approximately 4 degrees and approximately 15 degrees. The overall or effective club head loft is defined as an angle (θ shown in FIG. 2) between the face center 32 (or proximate the face center) of the striking face and a virtual vertical plane 33 when the golf club head is in the reference position. While the golf club head 10 includes an overall club head loft, the striking face 20 may include actual loft that varies as a function of face location. Such variation of actual loft of the striking face 20 is due to the roll curvature of the striking face 20. As such, when discussing actual loft characteristics of the striking face 20, it is assumed that the actual loft is described relative to the overall loft of the golf glub head 10. In order to measure actual loft at a desired measurement point, a loft and lie angle measurement device for wood-type club heads may be used. To measure loft at a desired measurement point, two vertical pins are used to measure the loft about the desired point which is equidistant between the two vertical pins.

[0036] FIGS. 3A-D illustrate coordinate maps of an example striking face 34 of a golf club head. The coordinate maps depict the striking face 20 such that the origin (i.e., 0,0 on the coordinate map) corresponds with the face center 32 and the origin has a relative loft of 0 and a relative face angle of 0, while the remaining locations of the striking face 20 are angularly offset relative to the origin. The coordinate map is further defined by the Y and Z axes shown and described in FIGS. 1 and 2. It is noted that the specific values shown on the coordinate maps are not limiting and merely show exemplary values for the inventive striking faces described herein. The specific values shown may also vary due to mathematical rounding and the relative values shown on the coordinate maps are not limiting and are merely exemplary. Specific values and ranges thereof will be described further herein below.

[0037] In some examples and following the second order polynomial surface equation described above, the striking face 34 may be defined using separate equations to represent the top half (y>0) and the bottom half (y≤0) of the striking face 34. As such, the striking face 34 may be defined by a piecewise equation as follows:x⁡(y, z)={p2⁢z2+p6⁢y2+p7⁢y2⁢zy>0p2⁢z2+p6⁢y2y≤0⁢ andp2<0,p6<0,p7<0

[0038] As shown in FIG. 3B, the striking face 34 includes an upper half (y>0) that has varying roll. For example, on the upper half (y>0) of the striking face 34, the roll radius on the heel side (z<0) is greater than the roll radius on the toe side (z>0). In some examples, the roll radius of the top half (y>0) of the striking face may vary between approximately 5 in. and 24 in, or preferably between approximately 6 in. and 22 in. Additionally, the roll radius along the Z-axis is substantially constant. In the provided example, the roll radius along the Z-axis may be approximately 10 in. However, it is to be understood that the specific values may vary. Additionally, in some examples, the roll radius and the bulge radius of the bottom half (y≤0) of the club face are also substantially constant.

[0039] As shown in FIG. 3C, the top half (y>0) of the striking face includes a loft on the toe side (z>0) that is greater than the loft of the heel side (z<0) for the same value of y. Additionally, the loft of the striking face 34 along the Z-axis is substantially equal to the loft at the origin (0,0). In some examples, the average added loft of the striking face 34 of the golf club head is 0.

[0040] Furthermore, and as shown in FIG. 3D, the top half (y>0) of the striking face 34 includes an open face angle, while the bottom half (y≤0) of the striking face 34 is neutral directly below the origin (0,0) along the Y-axis. In such an example, the average face angle of the entire striking face 34 is open.

[0041] To illustrate, the striking face 34 includes a first point (P1) located laterally toe-ward from the face center (0,0) along the Z-axis by a distance D1 between 25 mm and 35 mm and located vertically above the Z-axis in the Y-axis direction by a distance between 5 mm and 15 mm. The first point P1 is associated with a first loft and a first roll radius. The striking face 34 also includes a second point (P2) located laterally heel-ward from the face center (0,0) along the Z-axis by the distance D1 and located vertically above the Z-axis in the Y-axis direction by the distance D2. The second point P2 is associated with a second loft that is less than the first loft by at least 1 degree, and preferably at least 2 degrees. The second point is also associated with a second roll radius that is greater than the first roll radius by at least 5 in, preferably at least 7 in, and more preferably at least 10 in.

[0042] Following the example above, the striking face 34 may further include a third point P3 located laterally toe-ward from the face center (0,0) along the Z-axis by a distance D3 between 25 mm and 35 mm. The third point P3 is associated with a third loft that is less than the first loft. The third point P3 is also associated with a third roll radius that is greater than the first roll radius and less than the second roll radius. The striking face 34 may further include a fourth point P4 located laterally heel-ward from the face center (0,0) along the Z-axis by the distance D3. The fourth point P4 is associated with a fourth loft that is within 0.2 degrees or preferably within 0.1 degrees of the third loft. The fourth point P4 is also associated with a fourth roll radius that is within 0.5 in. or preferably within 0.2 in. of the third roll radius.

[0043] In some examples, the face center (0,0) is associated with a first face angle and a fifth roll radius. In such an example, the striking face 34 further includes a fifth point P5 located vertically below the center (0,0) along the Y-axis by a distance D5 between 5 mm and 20 mm. The fifth point P5 is associated with a second face angle that is within 0.2 degrees or preferably within 0.1 degree of the first face angle. The fifth point P5 is also associated with a sixth roll radius that is within 0.2 in. or preferably within 0.1 in. of the fifth roll radius. In some examples, a roll radius for at least 90%, preferably at least 95%, and more preferably greater than 95% of locations occupying the striking face below the virtual Z-axis is within 0.2 in. or preferably within 0.1 in. of the fifth roll radius.

[0044] The striking face 34 shown and described in FIGS. 3A-D may provide various benefits over a standard striking face. For example, the striking face 34 may provide improved shot dispersion when compared with a standard striking face. Furthermore, for impacts above the Z-axis, the striking face 34 will impart less draw spin (assuming a right-handed player), which results in straighter shots. Such a characteristic may prevent a “snap hook” that commonly occurs with a high-toe impact. Furthermore, for impacts below the Z-axis, the striking face 34 may launch a golf ball right of a target line. As such, the striking face 34 may be beneficial to a particular subset of players who may tend to hook the golf ball. Simulated test data of the striking face 34 is further described with respect to FIG. 12 below.

[0045] Furthermore, the striking face 34 may provide various benefits over other striking faces that attempt to reduce gear effect. For example, the striking face 34 described herein minimizes complex variability to regions of greatest impact for a subset of players. This provides a unique advantage over other striking faces that attempt to minimize gear effect. For example, the striking face 34 may minimize complex variability, reducing overall precision required in polishing, and / or reducing cost in forming such a striking face 34. As such, the striking face 34 described herein is effective to not overburden manufacturing resulting in a striking face 34 that effectively reduces gear effect.

[0046] FIGS. 4A-D illustrate coordinate maps of an example striking face 36 of a golf club head. As may be apparent from the figures, the striking face 36 shown in FIGS. 4A-D may be substantially inverse from the striking face 34 shown in FIGS. 3A-D. The coordinate maps depict the striking face 36 tilted relative to the plane defined by the Y and Z axes such that the origin (i.e., 0,0 on the coordinate map) has a loft of 0 and a face angle of 0. It is noted that the specific values shown on the coordinate maps are not limiting and merely show exemplary values for the inventive striking faces described herein. The specific values shown may also vary due to mathematical rounding and the relative values shown on the coordinate maps are not limiting and are merely exemplary. Specific values and ranges thereof will be described further herein below.

[0047] In some examples and following the second order polynomial surface equation described above, the striking face 36 may be defined using separate equations to represent the top half (y>0) and the bottom half (y≤0) of the striking face 36. As such, the striking face 36 may be defined by a piecewise equation as follows:x⁡(y, z)={p2⁢z2+p6⁢y2y>0p2⁢z2+p6⁢y2+p7⁢y2⁢zy≤0⁢ andp2<0,p6<0,p7>0

[0048] As shown in FIG. 4B, the striking face 36 includes a bottom half (y≤0) that has varying roll. For example, on the bottom half (y≤0) of the striking face, the roll radius on the toe side (z>0) is greater than the roll radius on the heel side (z<0). In some examples, the roll radius of the bottom half (y≤0) of the striking face may vary between approximately 5 in. and 24 in, or preferably between approximately 6 in. and 22 in. Additionally, the roll radius along the Z-axis is substantially constant. In the provided example, the roll radius along the Z-axis may be approximately 10 in. However, it is to be understood that the specific values may vary. Additionally, in some examples, the roll radius and the bulge radius of the top half (y>0) of the club face are also substantially constant.

[0049] As shown in FIG. 4C, the bottom half (y≤0) of the striking face 36 includes a loft on the heel side (z<0) that is less than the loft of the toe side (z>0) for the same value of y. Additionally, the loft of the striking face 36 along the Z-axis is substantially equal to the loft at the origin (0,0). In some examples, the average added loft of the striking face 36 of the golf club head is 0.

[0050] Furthermore, and as shown in FIG. 4D, the bottom half (y≤0) of the striking face 36 includes a closed face angle, while the top half (y>0) of the striking face 34 is neutral directly above the origin (0,0) along the Y-axis. In such an example, the average face angle of the entire striking face 36 is closed.

[0051] To illustrate, the striking face 36 includes a first point (P1) located laterally toe-ward from the face center (0,0) along the Z-axis by a distance D1 between 25 mm and 35 mm and located vertically below the Z-axis in the Y-axis direction by a distance between 5 mm and 15 mm. The first point P1 is associated with a first loft and a first roll radius. The striking face 34 also includes a second point (P2) located laterally heel-ward from the face center (0,0) along the Z-axis by the distance D1 and located vertically below the Z-axis in the Y-axis direction by the distance D2. The second point P2 is associated with a second loft that is less than the first loft by at least 1 degree, and preferably at least 2 degrees. The second point is also associated with a second roll radius that is less than the first roll radius by at least 5 in, preferably at least 7 in, and more preferably at least 10 in.

[0052] Following the example above, the striking face 36 may further include a third point located laterally toe-ward from the face center (0,0) along the Z-axis by a distance D3 between 25 mm and 35 mm. The third point is associated with a third loft that is greater than the first loft. The third point is also associated with a third roll radius that is less than the first roll radius and greater than the second roll radius. The striking face 36 may further include a fourth point P4 located laterally heel-ward from the face center (0,0) along the Z-axis by the distance D3. The fourth point is associated with a fourth loft that is within 0.2 degrees or preferably within 0.1 degrees of the third loft. The fourth point is also associated with a fourth roll radius that is within 0.5 in. or preferably within 0.2 in. of the third roll radius.

[0053] In some examples, the face center (0,0) is associated with a first face angle and a fifth roll radius. In such an example, the striking face 36 further includes a fifth point P5 located vertically above the center (0,0) along the Y-axis by a distance D5 between 5 mm and 20 mm. The fifth point P5 is associated with a second face angle that is within 0.2 degrees or preferably within 0.1 degree of the first face angle. The fifth point P5 is also associated with a sixth roll radius that is within 0.2 in. or preferably within 0.1 in. of the fifth roll radius. In some examples, a roll radius for at least 90%, preferably at least 95%, and more preferably greater than 95% of locations occupying the striking face above the virtual Z-axis is within 0.2 in. or preferably within 0.1 in. of the fifth roll radius.

[0054] The striking face 36 shown and described in FIGS. 4A-D may provide various benefits over a standard striking face. For example, the striking face 36 may provide improved shot dispersion when compared with a standard striking face. Furthermore, for impacts below the Z-axis, the striking face 36 will impart less fade or slice spin (assuming a right-handed player), which results in straighter shots. Such a characteristic may prevent a “slice” that commonly occurs with a low-heel impact. Furthermore, for impacts above the Z-axis, the striking face 36 may launch a golf ball left of a target line. As such, the striking face 36 may be beneficial to a particular subset of players who may tend to slice the golf ball, which is relatively common in mid-to-high handicap players. Simulated test data of the striking face 36 is further described with respect to FIG. 12 below.

[0055] Furthermore, the striking face 36 may provide various benefits over other striking faces that attempt to reduce gear effect. For example, the striking face 36 described herein minimizes complex variability to regions of greatest impact for a subset of players. This provides a unique advantage over other striking faces that attempt to minimize gear effect. For example, the striking face 36 may minimize complex variability, reducing overall precision required in polishing, and / or reducing cost in forming such a striking face 36. As such, the striking face 36 described herein is effective to not overburden manufacturing resulting in a striking face 36 that effectively reduces gear effect.

[0056] FIGS. 5A-D illustrate coordinate maps of an example striking face 38 of a golf club head. As may be apparent from the figures, the striking face 38 shown in FIGS. 5A-D may be a combination of the striking face 34 shown in FIGS. 3A-D and the striking face 26 shown in FIGS. 4A-D. The coordinate maps depict the striking face 38 tilted relative to the plane defined by the Y and Z axes such that the origin (i.e., 0,0 on the coordinate map) has a loft of 0 and a face angle of 0. It is noted that the specific values shown on the coordinate maps are not limiting and merely show exemplary values for the inventive striking faces described herein. The specific values shown may also vary due to mathematical rounding and the relative values shown on the coordinate maps are not limiting and are merely exemplary. Specific values and ranges thereof will be described further herein below.

[0057] In some examples and following the second order polynomial surface equation described above, the striking face 38 may be defined using separate equations to represent the top half (y>0) and the bottom half (y≤0) of the striking face 38. As such, the striking face 38 may be defined by a piecewise equation as follows:x⁡(y, z)={p2⁢z2+p6⁢y2+p7⁢t⁢y2⁢zy>0p2⁢z2+p6⁢y2+p7⁢b⁢y2⁢zy≤0⁢ andp2<0,p6<0,p7⁢t<0,p7⁢b>0

[0058] As shown in FIG. 5B, the striking face 36 includes a bottom half (y≤0) and a top half (y>0) that have varying roll. For example, on the top half (y>0) of the striking face 38, the roll radius on the heel side (z<0) is greater than the roll radius on the toe side (z>0). Conversely, the bottom half (y≤0) of the striking face includes the roll radius on the toe side (z>0) is greater than the roll radius on the heel side (z<0). In some examples, the roll radius of the top half (y>0) and the bottom half (y≤0) of the striking face may vary between approximately 5 in. and 24 in, or preferably between approximately 6 in. and 22 in. Additionally, the roll radius along the Z-axis is substantially constant. In the provided example, the roll radius along the Z-axis may be approximately 10 in. However, it is to be understood that the specific values may vary.

[0059] As shown in FIG. 5C, the top half (y>0) of the striking face 38 includes a loft on the toe side (z>0) that is greater than the loft of the heel side (z<0) for the same value of y. Conversely, the bottom half (y≤0) of the striking face 38 includes a loft on the heel side (z<0) that is less than the loft of the toe side (z>0) for the same value of y. Additionally, the loft of the striking face 38 along the Z-axis is substantially equal to the loft at the origin (0,0). In some examples, the average added loft of the striking face 36 of the golf club head is 0.

[0060] Furthermore, and as shown in FIG. 5D, the top half (y>0) of the striking face 38 includes an open face angle, while the bottom half (y≤0) of the striking face 38 includes a closed face angle. In such an example, the average face angle of the entire striking face 38 is neutral.

[0061] To illustrate, the striking face 38 includes a first point (P1) located laterally toe-ward from the face center (0,0) along the Z-axis by a distance D1 between 25 mm and 35 mm and located vertically above the Z-axis in the Y-axis direction by a distance between 5 mm and 15 mm. The first point P1 is associated with a first loft and a first roll radius. The striking face 38 also includes a second point (P2) located laterally heel-ward from the face center (0,0) along the Z-axis by the distance D1 and located vertically above the Z-axis in the Y-axis direction by the distance D2. The second point P2 is associated with a second loft that is less than the first loft by at least 1 degree, and preferably at least 2 degrees. The second point P2 is also associated with a second roll radius that is greater than the first roll radius by at least 5 in, preferably at least 7 in, and more preferably at least 10 in.

[0062] Following the example above, the striking face 38 may further include a third point P3 located laterally toe-ward from the face center (0,0) along the Z-axis by a distance D1 between 25 mm and 35 mm and located vertically below the Z-axis in the Y-axis direction by a distance between 5 mm and 15 mm. The third point P3 is associated with a third loft that is within 6 degrees, preferably within 5 degrees, and more preferably within 3 degrees of the second loft. In some examples, the third point P3 is associated with a relative absolute loft (i.e., the absolute value of loft relative to a datum such as face center) that is within 0.5 degrees, preferably within 0.2 degrees, and more preferably within 0.1 degree of a relative absolute loft associated with the second point P2 (where each point on the face is relative to the same datum such as the face center). The third point P3 is also associated with a third roll radius that is within 1.5 in., preferably within 1.0 in, or preferably within 0.5 in. of the second roll radius. The striking face 34 also includes a fourth point P4 located laterally heel-ward from the face center (0,0) along the Z-axis by the distance D1 and located vertically below the Z-axis in the Y-axis direction by the distance D2. Similarly, the fourth point P4 is associated with a fourth loft that is within 6 degrees, preferably within 5 degrees, and more preferably within 3 degrees of the first loft. In some examples, the fourth point P4 is associated with a relative absolute loft (i.e., the absolute value of loft relative to a datum such as face center) that is within 0.5 degrees, preferably within 0.2 degrees, and more preferably within 0.1 degree of a relative absolute loft associated with the first point P1 (where each point on the face is relative to the same datum such as the face center). The fourth point is also associated with a fourth roll radius that is within 1.5 in., preferably within 1.0 in, or preferably within 0.5 in. of the first roll radius.

[0063] In some examples, the face center (0,0) is associated with a first face angle and a fifth roll radius. In such an example, the striking face 36 further includes a fifth point P5 located vertically above the center (0,0) along the Y-axis by a distance D5 between 5 mm and 20 mm. The fifth point P5 is associated with a second face angle that is within 0.2 degrees or preferably within 0.1 degree of the first face angle. The fifth point P5 is also associated with a sixth roll radius that is within 0.2 in. or preferably within 0.1 in. of the fifth roll radius. In some examples, a roll radius for at least 90%, preferably at least 95%, and more preferably greater than 95% of locations occupying the striking face above the virtual Z-axis is within 0.2 in. or preferably within 0.1 in. of the fifth roll radius.

[0064] The striking face 38 shown and described in FIGS. 5A-D may provide various benefits over a standard striking face. For example, the striking face 38 may provide improved shot dispersion when compared with a standard striking face. In some examples, for impacts above the Z-axis, the striking face 38 will impart less draw spin (assuming a right-handed player), which results in straighter shots. Furthermore, for impacts below the Z-axis, the striking face 38 will impart less fade or slice spin (assuming a right-handed player), which results in straighter shots. Simulated test data of the striking face 36 is further described with respect to FIG. 12 below.

[0065] Furthermore, the striking face 38 may provide various benefits over other striking faces that attempt to reduce gear effect. For example, the striking face 38 described herein blends two advantageous striking face designs, while maintaining a substantially neutral central region of the striking face 38. As such, the striking face 38 provides benefit for off center shots but maintains maximal carry and accuracy for impacts that occur proximate the face center.

[0066] FIGS. 6A-D illustrate coordinate maps of an example striking face 40 of a golf club head. The coordinate maps depict the striking face 40 tilted relative to the plane defined by the Y and Z axes such that the origin (i.e., 0,0 on the coordinate map) has a loft of 0 and a face angle of 0. It is noted that the specific values shown on the coordinate maps are not limiting and merely show exemplary values for the inventive striking faces described herein. The specific values shown may also vary due to mathematical rounding and the relative values shown on the coordinate maps are not limiting and are merely exemplary. Specific values and ranges thereof will be described further herein below.

[0067] In some examples and following the second order polynomial surface equation described above, the striking face 40 may be defined using separate equations to represent a toe half (z>0) and a heel half (z≤0) of the striking face 40. As such, the striking face 40 may be defined by a piecewise equation as follows:x⁡(y, z)={p2⁢z2+p5⁢yz2+p6⁢y2z>0p2⁢z2+p6⁢y2z≤0⁢ andp2<0,p6<0,p5<0

[0068] As shown in FIG. 6A, the striking face 40 includes a toe half (z>0) that has varying bulge. For example, on the toe half (z>0) of the striking face 40, the bulge radius on the bottom half (y≤0) is greater than the bulge radius top side (y>0). In some examples, the bulge radius of the toe half (z>0) of the striking face may vary between approximately 7 in. and 26 in, or preferably between approximately 8 in. and 24 in. Additionally, the bulge radius along the Y-axis is substantially constant. In the provided example, the bulge radius along the Z-axis may be approximately 13 in. However, it is to be understood that the specific values may vary. Additionally, in some examples, the bulge radius of the heel half (z≤0) of the club face is also substantially constant.

[0069] As shown in FIG. 6C, the toe half (z>0) of the striking face 40 includes a loft on the toe side (z>0) that is greater than the loft of the heel half (z≤0) for the same value of y As such, the loft of the striking face 40 varies along the Z-axis. Furthermore, the average added loft of the striking face 40 of the golf club head is greater than 0.

[0070] Furthermore, and as shown in FIG. 6D, the toe half (z>0) of the striking face 40 includes a face angle on the top half (y>0) that is more open than a face angle on the bottom half (y≤0) for the same value of z. In such an example, the average face angle of the entire striking face 40 is neutral.

[0071] The striking face 40 shown and described in FIGS. 6A-D may provide various benefits over a standard striking face. For example, the striking face 64 may provide improved shot dispersion when compared with a standard striking face. Furthermore, for impacts toe-ward of the Y-axis, the striking face 40 will impart less draw spin (assuming a right-handed player), which results in straighter shots. Such a characteristic may prevent a “snap hook” that commonly occurs with a high-toe impact. Furthermore, since the striking face 40 includes an average added loft greater than 0, the striking face 40 may launch the ball higher than a standard face. As such, the striking face 40 may be beneficial to a particular subset of players who may tend to hook the golf ball and / or for players that tend to hit the ball undesirably low. Simulated test data of the striking face 40 is further described with respect to FIG. 12 below.

[0072] Furthermore, the striking face 40 may provide various benefits over other striking faces that attempt to reduce gear effect. For example, the striking face 40 described herein minimizes complex variability to regions of greatest impact for a subset of players. This provides a unique advantage over other striking faces that attempt to minimize gear effect. For example, the striking face 40 may minimize complex variability, reducing overall precision required in polishing, and / or reducing cost in forming such a striking face 40. As such, the striking face 40 described herein is effective to not overburden manufacturing resulting in a striking face 40 that effectively reduces gear effect.

[0073] FIGS. 7A-D illustrate coordinate maps of an example striking face 42 of a golf club head. The coordinate maps depict the striking face 42 tilted relative to the plane defined by the Y and Z axes such that the origin (i.e., 0,0 on the coordinate map) has a loft of 0 and a face angle of 0. It is noted that the specific values shown on the coordinate maps are not limiting and merely show exemplary values for the inventive striking faces described herein. The specific values shown may also vary due to mathematical rounding and the relative values shown on the coordinate maps are not limiting and are merely exemplary. Specific values and ranges thereof will be described further herein below.

[0074] In some examples and following the second order polynomial surface equation described above, the striking face 42 may be defined using separate equations to represent a toe half (z>0) and a heel half (z≤0) of the striking face 42. As such, the striking face 42 may be defined by a piecewise equation as follows:x⁡(y, z)={p2⁢z2+p6⁢y2z>0p2⁢z2+p5⁢yz2+p6⁢y2z≤0⁢ andp2<0,p6<0,p5>0

[0075] As shown in FIG. 7B, the striking face 42 includes a toe half (z>0) that has substantially constant bulge and roll. Furthermore, the heel half (z≤0) of the striking face 42, the bulge radius of the bottom half (y≤0) is less than the bulge radius of the top half (y>0). In some examples, the bulge radius of the heel half (z≤0) of the striking face may vary between approximately 7 in. and 26 in, or preferably between approximately 8 in. and 24 in. Additionally, the bulge radius along the Y-axis is substantially constant. In the provided example, the bulge radius along the Z-axis may be approximately 13 in. However, it is to be understood that the specific values may vary.

[0076] As shown in FIG. 7C, the heel half (z≤0) of the striking face 42 includes a loft on the toe side (z>0) that is greater than the loft of the heel half (z≤0) for the same value of y. As such, the loft of the striking face 42 varies along the Z-axis. Furthermore, the average added loft of the striking face 42 of the golf club head is less than 0.

[0077] Furthermore, and as shown in FIG. 7D, the heel half (z≤0) of the striking face 42 includes a face angle on the top half (y>0) that is less closed than a face angle on the bottom half (y≤0) for the same value of z. In such an example, the average face angle of the entire striking face 42 is neutral.

[0078] The striking face 42 shown and described in FIGS. 7A-D may provide various benefits over a standard striking face. For example, the striking face 42 may provide improved shot dispersion when compared with a standard striking face. Furthermore, for impacts heel-ward of the Y-axis, the striking face 42 will impart less fade spin (assuming a right-handed player), which results in straighter shots. Such a characteristic may prevent a “slice” that commonly occurs with a low-heel impact. Simulated test data of the striking face 40 is further described with respect to FIG. 12 below.

[0079] Furthermore, the striking face 42 may provide various benefits over other striking faces that attempt to reduce gear effect. For example, the striking face 42 described herein minimizes complex variability to regions of greatest impact for a subset of players. This provides a unique advantage over other striking faces that attempt to minimize gear effect. For example, the striking face 42 may minimize complex variability, reducing overall precision required in polishing, and / or reducing cost in forming such a striking face 42. As such, the striking face 42 described herein is effective to not overburden manufacturing resulting in a striking face 42 that effectively reduces gear effect.

[0080] FIGS. 8A-D illustrate coordinate maps of an example striking face 44 of a golf club head. As may be apparent from the figures, the striking face 44 shown in FIGS. 8A-D may be a combination of the striking face 40 shown in FIGS. 6A-D and the striking face 42 shown in FIGS. 7A-D. The coordinate maps depict the striking face 44 tilted relative to the plane defined by the Y and Z axes such that the origin (i.e., 0,0 on the coordinate map) has a loft of 0 and a face angle of 0. It is noted that the specific values shown on the coordinate maps are not limiting and merely show exemplary values for the inventive striking faces described herein. The specific values shown may also vary due to mathematical rounding and the relative values shown on the coordinate maps are not limiting and are merely exemplary. Specific values and ranges thereof will be described further herein below.

[0081] In some examples and following the second order polynomial surface equation described above, the striking face 44 may be defined using separate equations to represent a toe half (z>0) and a heel half (z≤0) of the striking face 44. As such, the striking face 44 may be defined by a piecewise equation as follows:x⁡(y, z)={p2⁢z2+p5⁢t⁢yz2+p6⁢y2z>0p2⁢z2+p5⁢h⁢yz2+p6⁢y2z≤0⁢ andp2<0,p6<0,p5⁢t>0,p5⁢h<0

[0082] As shown in FIG. 8A, the striking face 44 includes a toe half (z>0) and a heel half (z≤0) that have varying bulge. For example, the toe half (z>0) of the striking face 44 includes a bulge radius on the bottom half (y≤0) is greater than the bulge radius top side (y>0). Additionally, the heel half (z≤0) of the striking face includes a bulge radius of the bottom half (y≤0) that is less than the bulge radius of the top half (y>0). In some examples, the bulge radius of the toe half (z>0) and the heel half (z≤0) of the striking face 44 may vary between approximately 7 in. and 26 in, or preferably between approximately 8 in. and 24 in. Additionally, the bulge radius along the Y-axis may be substantially constant.

[0083] As shown in FIG. 8C, the striking face 44 includes a loft on the toe side (z>0) that is greater than the loft of the heel half (z≤0) for the same value of y. In such an example, the loft of the striking face 44 varies along the Z-axis. Furthermore, the average added loft of the striking face 44 of the golf club head is 0.

[0084] Furthermore, and as shown in FIG. 8D, the toe half (z>0) of the striking face 44 includes a face angle on the top half (y>0) that is more open than a face angle on the bottom half (y≤0) for the same value of z. Similarly, the heel half (z≤0) of the striking face 44 includes a face angle on the top half (y>0) that is less closed than a face angle on the bottom half (y≤0) for the same value of z. In such an example, the average face angle of the entire striking face 44 is neutral.

[0085] The striking face 44 shown and described in FIGS. 8A-D may provide various benefits over a standard striking face. For example, the striking face 44 may provide improved shot dispersion when compared with a standard striking face. In some examples, for toe-side impacts, the striking face 44 will impart less draw spin (assuming a right-handed player), which results in straighter shots. Furthermore, for heel-side impacts, the striking face 44 will impart less fade or slice spin (assuming a right-handed player), which results in straighter shots. Simulated test data of the striking face 44 is further described with respect to FIG. 12 below.

[0086] Furthermore, the striking face 44 may provide various benefits over other striking faces that attempt to reduce gear effect. For example, the striking face 44 described herein blends two advantageous striking face designs, while maintaining a substantially neutral central region of the striking face 44. As such, the striking face 44 provides benefit for off center shots but maintains maximal carry and accuracy for impacts that occur proximate the face center.

[0087] According to another example, FIGS. 9 and 10 depict a golf club head 10 that may be substantially the same as the golf club head shown and described with respect to FIGS. 1 and 2. However, the golf club head 10 includes a striking face 46 having a striking face 46 with another configuration. The striking face 46 of the golf club head 10 includes substantially constant bulge and roll curvature.

[0088] In some examples, the golf club head 10 includes a virtual vertical plane 48 passing through the face center 32. Referring now to FIG. 10, the golf club head 10 includes a virtual striking face plane 50 that extends tangent to the face center 32. The golf club head 10 also includes an axis of rotation 52 passing through the face center 32 and extending perpendicular to the virtual striking face plane 50. The golf club head 10 further includes a virtual transverse plane 54 coplanar with the axis of rotation 52 and extending in a heel-to-toe direction.

[0089] The golf club head 10 further includes a virtual bulge plane 56 that is coplanar with the axis of rotation 52 and defined such that all points on the striking face 46 and in the virtual bulge plane 56 have substantially the same bulge radius. As shown in FIG. 9, the virtual bulge plane is rotationally offset by 0 of at least 18 degrees counterclockwise about the axis of rotation from the virtual transverse plane 54. In some examples, the virtual bulge plane 56 is rotationally offset counterclockwise from the virtual transverse plane 54 by between 16 and 40 degrees, or preferably between 18 and 30 degrees.

[0090] Similarly, the golf club head 10 includes a virtual roll plane 58 that is coplanar with the axis of rotation 52 and is defined such that all points on the striking face 46 and in the virtual roll plane 58 have substantially the same roll radius. As shown in FIG. 9, the virtual roll plane 58 is rotationally offset by 0 of at least 18 degrees counterclockwise about the axis of rotation 52 from the virtual vertical plane 48. In some examples, the virtual roll plane 58 is rotationally offset counterclockwise from the virtual vertical plane 48 by between 16 and 40 degrees, or preferably between 18 and 30 degrees.

[0091] To illustrate, and as shown in FIGS. 11A-11D, the striking face 46 includes a first point P1 located laterally toe-ward from the face center (0,0) along the Z-axis by a distance between 25 mm and 35 mm. The first point P1 is associated with a first loft, a first bulge radius, and a first roll radius. The striking face 46 further includes a second point P2 that is located laterally heel-ward from the face center 32 along the Z-axis by the distance D1. The second point P2 is associated with a second loft that is less than the first loft by at least 0.5 degrees, or preferably by at least 1 degree, or more preferably by at least 1.5 degrees. Furthermore, the second point P2 is associated with a second bulge radius that is within 0.2 in., or preferably within 0.1 in. of the first bulge radius. The second point is also associated with a second roll radius that is within 0.2 in., or preferably within 0.1 in. of the first roll radius.

[0092] Furthermore, the face center (0,0) is associated with a third bulge radius that is within 0.2 in., or preferably within 0.1 in. of the first bulge radius. The face center (0,0) is also associated with a third roll radius that is within 0.2 in., or preferably within 0.1 in. of the first roll radius. In some examples, a bulge radius for at least 90%, or preferably at least 92%, or more preferably at least 95% of locations occupying the striking face 46 is within 0.2 in, or preferably within 0.1 in. of the first bulge radius. Similarly, a roll radius for at least 90%, or preferably at least 92%, or more preferably at least 95% of locations occupying the striking face 46 is within 0.2 in, or preferably within 0.1 in. of the first roll radius.

[0093] The striking face 46 shown and described in FIGS. 9-11 may provide various benefits over a standard striking face. For example, the striking face 46 may provide improved shot dispersion when compared with a standard striking face. In some examples, for impacts above the Z-axis, the striking face 46 will impart less draw spin (assuming a right-handed player), which results in straighter shots. Furthermore, for impacts below the Z-axis, the striking face 46 will impart less fade or slice spin (assuming a right-handed player), which results in straighter shots. Simulated test data of the striking face 46 is further described with respect to FIG. 12 below.

[0094] Furthermore, the striking face 46 may provide various benefits over other striking faces that attempt to reduce gear effect. For example, the striking face 46 described herein blends two advantageous striking face designs, while maintaining a substantially neutral central region of the striking face 46. As such, the striking face 46 provides benefit for off center shots but maintains maximal carry and accuracy for impacts that occur proximate the face center.

[0095] FIG. 12 depicts simulated test data for the striking faces described herein. The first column depicts the difference in mean distance (in yards), the second column depicts the difference in standard deviation distance (in yards), and the third column depicts the difference in standard deviation distance (in yards). The data shown in FIG. 12 is compared to simulated test data of a standard striking face having substantially constant bulge and roll curvature. As shown in FIG. 12, each of the striking faces provide increased distance, while reducing offline shots.

[0096] In the foregoing discussion, the present invention has been described with reference to specific exemplary aspects thereof. However, it will be evident that various modifications and changes may be made to these exemplary aspects without departing from the broader spirit and scope of the invention. Accordingly, the foregoing discussion and the accompanying drawings are to be regarded as merely illustrative of the present invention rather than as limiting its scope in any manner.

Examples

Embodiment Construction

[0025]In some aspects of the present disclosure, referring to FIG. 1, a golf club head 10 is shown. The golf club head 10 includes a crown portion 12 (or top portion) and a sole portion 14 opposite the crown 12. The golf club head 10 further includes a toe portion 16 and a heel portion 18 opposite the toe portion 16. The golf club head 10 also includes a striking face 20 and a hosel 22 that extends from the heel portion 18. The hosel 22 includes an internal hosel bore 24 configured to receive a shaft (not shown) therein. The internal hosel bore 24 defines a central axis, i.e., a hosel axis 26.

[0026]The striking face 20 is generally planar (or quasi-planar), but includes curvature of relatively high radius (i.e., no less than 6 in). Furthermore, the striking face 20 includes bulge and roll curvature. Bulge refers to the curvature of the striking face 20 in a generally heel-to-toe direction, while roll refers to the curvature of the striking face in a generally top-to-bottom direction...

Claims

1. A golf club head comprising:a volume greater than 400 cubic centimeters;a crown portion;a sole portion opposite the crown portion;a toe portion;a heel portion opposite the toe portion; anda striking face having:a face center;a first point located laterally toe-ward from the face center by a first distance D1 between 25 mm and 35 mm, the first point associated with a first loft, a first bulge radius, and a first roll radius; anda second point located laterally heel-ward from the face center by the first distance D1, the second point associated with a second loft that is less than the first loft by at least 0.5 degrees, a second bulge radius that is within 0.2 in of the first bulge radius, and a second roll radius that is within 0.2 in of the first roll radius.

2. The golf club head of claim 1, wherein the face center is associated with a third bulge radius that is within 0.2 in of the first bulge radius, and the face center is associated with a third roll radius that is within 0.2 in of the first roll radius.

3. The golf club head of claim 2, wherein the third bulge radius is within 0.1 in of the first bulge radius, and the third roll radius is within 0.1 in of the first roll radius.

4. The golf club head of claim 1, wherein a bulge radius for at least 90% of locations occupying the striking face is within 0.2 in of the first bulge radius.

5. The golf club head of claim 1, wherein a roll radius for at least 90% of locations occupying the striking face is within 0.2 in of the first roll radius.

6. The golf club head of claim 1, wherein the second bulge radius is within 0.1 in of the first bulge radius.

7. The golf club head of claim 1, wherein the second roll radius is within 0.1 in of the first roll radius.

8. The golf club head of claim 1, wherein the second loft is less than the first loft by at least 1.0 degree.

9. The golf club head of claim 1, wherein the second loft is less than the first loft by at least 1.5 degrees.

10. The golf club head of claim 1 that, when oriented in a reference position relative to a virtual ground plane, further comprises:a virtual vertical plane passing through the face center;a virtual striking face plane extending tangent to the face center;an axis of rotation passing through the face center and extending perpendicular to the virtual striking face plane;a virtual transverse plane coplanar with the axis of rotation and extending in a heel to toe direction;a virtual bulge plane coplanar with the axis of rotation and defined such that all points on the striking face and in the virtual bulge plane have substantially the same bulge radius, wherein the virtual bulge plane is rotationally offset by at least 18 degrees counterclockwise about the axis of rotation from the virtual transverse plane; anda virtual roll plane coplanar with the axis of rotation and defined such that all points on the striking face and in the virtual roll plane have substantially the same roll radius, wherein the virtual roll plane is rotationally offset by at least 18 degrees counterclockwise about the axis of rotation from the virtual vertical plane.

11. The golf club head of claim 10, wherein the virtual bulge plane is rotationally offset from the virtual transverse plane by between 18 and 30 degrees and the virtual roll plane is rotationally offset from the virtual vertical plane by between 18 and 30 degrees counterclockwise.

12. A golf club head that, when oriented in a reference position relative to a virtual ground plane, comprises:a volume greater than 400 cubic centimeters;a crown portion;a sole portion opposite the crown portion;a toe portion;a heel portion opposite the toe portion;a striking face having:a face center;a virtual Y-axis having an origin coincident with the face center, the virtual Y-axis extending in a direction perpendicular to the virtual ground plane and having a positive Y-axis direction that extends from the origin towards the crown portion;a virtual Z-axis extending from the origin in a direction that is parallel to the virtual ground plane and having a positive Z-axis direction that extends from the origin towards the toe portion;a first point located laterally toe-ward from the face center along the virtual Z-axis by a distance D1 between 25 mm and 35 mm and located vertically above the virtual Z-axis in the virtual Y-axis direction by a distance D2 between 5 mm and 15 mm, the first point associated with a first loft and a first roll radius; anda second point located laterally heel-ward from the face center along the virtual Z-axis by the distance D1 and located vertically above the virtual Z-axis in the Y-axis direction by the distance D2, the second point associated with a second loft that is less than the first loft by at least 1 degree and a second roll radius that is greater than the first roll radius by at least 5 in.

13. The golf club head of claim 12, wherein the striking face further comprises:a third point located laterally toe-ward from the face center along the virtual Z-axis by a distance D3 between 25 mm and 35 mm, the third point associated with a third loft that is less than the first loft and a third roll radius that is greater than the first roll radius and less than the second roll radius; anda fourth point located laterally heel-ward from the face center along the virtual Z-axis by the distance D3, the fourth point associated with a fourth loft that is within 0.2 degrees of the third loft and a fourth roll radius that is within 0.5 in of the third roll radius,wherein the face center is associated with a fifth roll radius that is within 0.5 in of the third roll radius.

14. The golf club head of claim 12, wherein the striking face further comprises:a third point located laterally toe-ward from the face center along the virtual Z-axis by a distance D3 between 25 and 35 mm and located vertically below the virtual Z-axis in the virtual Y-axis direction by a distance D4 between 5 mm and 15 mm, the third point associated with a third loft that is within 0.5 degrees of the second loft and a third roll radius that is within 0.5 in of the second roll radius; anda fourth point located laterally heel-ward from the face center by the distance D3 and located vertically below the virtual Z-axis in the virtual Y-axis direction by the distance D4, the fourth point associated with a fourth loft that is within 0.5 degrees of the first loft and a fourth roll radius that is within 0.5 in of the first roll radius.

15. The golf club head of claim 12, wherein the face center is associated with a first face angle and a third roll radius, and the golf club head further comprises:a third point located vertically below the face center along the virtual Y-axis by a distance D3 between 5 mm and 20 mm, the third point associated with a second face angle that is within 0.2 degrees of the first face angle and a fourth roll radius that is within 0.2 in of the third roll radius.

16. The golf club head of claim 15, wherein a roll radius for at least 90% of locations occupying the striking face below the virtual Z-axis is within 0.2 in of the third roll radius.

17. A golf club head, when oriented in a reference position relative to a virtual ground plane, comprising:a volume greater than 400 cubic centimeters;a crown portion;a sole portion opposite the crown portion;a toe portion;a heel portion opposite the toe portion;a striking face having:a face center;a virtual Y-axis having an origin coincident with the face center, the virtual Y-axis extending in a direction perpendicular to the virtual ground plane and having a positive Y-axis direction that extends from the origin towards the crown portion;a virtual Z-axis extending from the origin in a direction that is parallel to the virtual ground plane and having a positive Z-axis direction that extends from the origin towards the toe portion;a first point located laterally toe-ward from the face center along the virtual Z-axis by a distance D1 between 25 mm and 35 mm and located vertically below the virtual Z-axis in the virtual Y-axis direction by a distance D2 between 5 mm and 15 mm, the first point associated with a first loft and a first roll radius; anda second point located laterally heel-ward from the face center along the virtual Z-axis by the distance D1 and located vertically below the virtual Z-axis in the virtual Y-axis direction by the distance D2, the second point associated with a second loft that is less than the first loft by at least 1 degree and a second roll radius that is that is less than the first roll radius by at least 5 in.

18. The golf club head of claim 17, wherein the striking face further comprises:a third point located laterally toe-ward from the face center along the virtual Z-axis by a distance D3 between 25 mm and 35 mm, the third point associated with a third loft that is greater than the first loft and a third roll radius that is greater than the first roll radius and less than the second roll radius; anda fourth point located laterally heel-ward from the face center along the virtual Z-axis by the distance D3, the fourth point associated with a fourth loft that is within 0.2 degrees of the third loft and a fourth roll radius that is within 0.5 in of the third roll radius,wherein the face center is associated with a fifth roll radius that is within 0.5 in of the third roll radius.

19. The golf club head of claim 18, wherein the face center is associated with a first face angle and the striking face further comprises a fifth point located vertically above the face center along the virtual Y-axis by a distance D4 between 5 mm and 20 mm, the fifth point associated with a second face angle that is within 0.2 degrees of the first face angle and the fifth point associated with a sixth roll radius that is within 0.2 in of the fifth roll radius.

20. The golf club head of claim 18, wherein a roll radius for at least 90% of locations occupying the striking face above the virtual horizontal plane is within 0.2 in of the fifth roll radius.

21. The golf club head of claim 17, wherein the striking face further comprises:a third point located laterally toe-ward from the face center along the virtual Z-axis by a distance D3 between 25 mm and 35 mm and located vertically above the virtual Z-axis in the virtual Y-axis direction by a distance D4 between 5 mm and 15 mm, the third point having a third loft that is within 0.5 degrees of the second loft and a third roll radius that is within 0.5 in of the second roll radius; anda fourth located laterally heel-ward from the face center along the virtual Z-axis by the distance D3 and located vertically above the virtual Z-axis in the virtual Y-axis direction by the distance D4, the fourth point associated with a fourth loft that is within 0.5 degrees of the first loft and a fourth roll radius that is within 0.5 in of the first roll radius.

Images