KR20250001564U - Golf club head - Google Patents

Abstract

A golf club head formed of a steel alloy capable of improving the center of gravity (CG) location while maintaining the traditional external dimensions of the golf club head. More specifically, the golf club head according to the present invention achieves a relatively low CG while maintaining the traditional external dimensions by reducing the mass contributed by the crown, striking face, and hosel, and strategically redistributing this mass within and/or near the sole of the golf club head.

Description

Golf club head {GOLF CLUB HEAD}

Cross-reference to related applications

This application is a continuation-in-part (CIP) of co-pending U.S. patent application Ser. No. 18/459,825, filed September 1, 2023, which is a continuation-in-part (CIP) of U.S. patent application Ser. No. 17/589,471, filed January 31, 2022, and now U.S. patent 11,679,311, which is a CIP of U.S. patent application Ser. No. 18/327,771, filed June 1, 2023, the disclosures of which are incorporated by reference in their entireties.

Technology field

The present invention relates generally to golf club heads, and more particularly to rigid fairway woods having a low center of gravity (CG).

According to the rules of golf, a golfer is permitted to carry 14 clubs. In an ideal world, each club serves a specific purpose. For example, the driver is primarily used to hit the golf ball off the tee, and long distance is desirable. Fairway woods and hybrids are used to send the ball farther, but not as far as the driver. Fairway woods and hybrids are often used off the tee when a golfer wants to hit the ball straighter or shorter than with the driver. Fairway woods and hybrids are also often used to hit the ball straight from the ground without a tee. Iron-type golf clubs are used to hit the ball straighter and shorter, with a greater emphasis on accuracy.

These various golf clubs are each specifically designed to maximize their effectiveness for specific purposes. Fairway woods and hybrids require a unique balance of performance and aesthetics, as they demand distance and accuracy not only from tee shots but also when hitting the ball off the ground.

Given the wide range of uses for fairway woods and hybrids, particularly for shots hit directly from the ground without a tee, a low CG is desirable to facilitate easier launch of the golf shot. Most fairway woods and hybrids are primarily made of steel alloys. Typically, the CG of a fairway wood or hybrid can be lowered by utilizing one of several undesirable design features.

For example, the CG can be lowered by reducing the peak crown height of a golf club. While reducing the peak crown height of a golf club can lower the CG, the resulting design tradeoff is undesirable. A lower peak crown height reduces the aesthetic appeal of the golf club head. Specifically, the golf club head may appear smaller or at least smaller than a conventional golf club head, which can reduce the golfer's confidence when preparing for a golf shot.

Likewise, the striking face height (e.g., ground-to-top radius) of a golf club can be reduced. As mentioned above, this not only detracts from the aesthetics of the golf club, but also physically reduces the striking face size, making it more difficult to hit.

Additionally, golf club heads can manipulate the CG position by combining various materials. For example, a golf club crown can be made of any of several materials with lower densities than steel, such as titanium or composites. While combining various materials is useful for manipulating the CG of a golf club head, it can be costly and poses numerous potential manufacturing challenges due to combining different materials.

Therefore, there is a need for a steel structure fairway wood type golf club head that can achieve a low CG without changing the external dimensions of a conventional fairway wood type golf club head.

One aspect of the present invention is a golf club head comprising a striking face defining a face center, a crown, a sole opposite the crown, a heel, a toe opposite the heel, and a hosel adjacent to the heel and configured to couple the golf club head to a shaft, wherein the striking face, the crown, the sole, the heel, the toe, and the hosel each comprise a steel alloy, wherein an X-axis is defined as a horizontal axis tangent to the face center of the striking face and having a positive direction in a direction toward the heel of the golf club head, a Y-axis is a vertical axis perpendicular to the X-axis and having a positive direction in a direction toward the crown of the golf club head, a Z-axis is perpendicular to both the X-axis and the Y-axis and having a positive direction in a direction toward the front of the golf club head, and the origins of the X-axis, the Y-axis, and the Z-axis are located at a center of gravity (CG) of the golf club head, wherein the volume of the golf club head is about 100 cc to about 200 cc, and wherein a minimum crown thickness of the crown is about 0.3 mm to about 0.6 mm, the sole has a maximum sole thickness, the peak crown height of the golf club head is greater than about 35.0 mm, the ground-top radius measurement of the golf club head is greater than about 31.0 mm, the golf club head has a CG-Yg such that the distance from the ground to the CG along the y-axis is less than about 16.0 mm, and the ΔYccg of the golf club head is from about 22.0 mm to about 28.0 mm, and the ΔYccg is expressed by the equation , and the maximum sole thickness to minimum crown thickness ratio of the golf club head is about 4.0 or greater, and the maximum sole thickness to minimum crown thickness ratio is defined by the following equation:

,

The mass of the golf club head below an X-Z plane set at a vertical height from the ground equal to 25% of the peak crown height measurement is greater than about 45% of the total mass of the golf club head, the mass of the golf club head below an X-Z plane set at a vertical height from the ground equal to 20% of the peak crown height measurement is greater than about 38% of the total mass of the golf club head, the mass of the golf club head below an X-Z plane set at a vertical height from the ground equal to 15% of the peak crown height measurement is greater than about 27% of the total mass of the golf club head, and the mass of the golf club head below an X-Z plane set at a vertical height from the ground equal to 10% of the peak crown height measurement is greater than about 12% of the total mass of the golf club head.

According to another aspect of the present invention, a golf club head includes a striking face defining a face center, a crown, a sole opposite the crown, a heel, a toe opposite the heel, and a hosel adjacent to the heel and configured to couple the golf club head to a shaft, wherein the striking face, the crown, the sole, the heel, the toe, and the hosel each comprise a steel alloy, wherein an X-axis is defined as a horizontal axis tangent to the face center of the striking face and having a positive direction in a direction toward the heel of the golf club head, a Y-axis is a vertical axis perpendicular to the X-axis and having a positive direction in a direction toward the crown of the golf club head, a Z-axis is perpendicular to both the X-axis and the Y-axis and having a positive direction in a direction toward the front of the golf club head, and the origins of the X-axis, the Y-axis, and the Z-axis are located at a center of gravity (CG) of the golf club head, and the volume of the golf club head is about 100 cc to about 200 cc, and a minimum crown thickness of the crown is about 0.3 mm to about 0.6 mm, and the sole has a maximum sole thickness, and the maximum sole thickness to minimum crown thickness ratio of the golf club head is about 4.0 or greater, and the maximum sole thickness to minimum crown thickness ratio is defined by the following equation:

.

According to another aspect of the present invention, a golf club head includes a striking face defining a face center, a crown, a sole opposite the crown, a heel, a toe opposite the heel, and a hosel adjacent to the heel and configured to couple the golf club head to a shaft, wherein the striking face, the crown, the sole, the heel, the toe, and the hosel each comprise a steel alloy, wherein an X-axis is defined as a horizontal axis tangent to the face center of the striking face and having a positive direction in a direction toward the heel of the golf club head, a Y-axis is a vertical axis perpendicular to the X-axis and having a positive direction in a direction toward the crown of the golf club head, a Z-axis is perpendicular to both the X-axis and the Y-axis and having a positive direction in a direction toward the front of the golf club head, and the origins of the X-axis, the Y-axis, and the Z-axis are located at a center of gravity (CG) of the golf club head, and the volume of the golf club head is about 100 cc to about 200 cc, and a minimum crown thickness of the crown is about 0.3 mm to about 0.6 mm, wherein the sole has a maximum sole thickness, and the mass of the golf club head under an X-Z plane set at a vertical height from the ground equal to 25% of the peak crown height measurement is greater than about 45% of the total mass of the golf club head, and the mass of the golf club head under an X-Z plane set at a vertical height from the ground equal to 15% of the peak crown height measurement is greater than about 27% of the total mass of the golf club head. In another aspect of the present invention, the maximum face thickness to sole return thickness ratio of the golf club head is from about 1.70 to about 2.18, and the maximum face thickness to sole return thickness ratio is defined by the following equation:

.

According to another aspect of the present invention, the striking face has a sole return.

According to another aspect of the present invention, the striking face has a variable face thickness profile further comprising a transition portion having a thickness biased toward the crown, an upper transition portion having an upper transition slope, and a lower transition portion having a lower transition slope, wherein the upper transition slope is greater than the lower transition slope.

According to another aspect of the present invention, the transition portion with the thickness biased toward the crown has an aspect ratio greater than about 5.

According to another aspect of the present invention, the sole return has an initial front thickness greater than the middle thickness, and the sole return has a terminal thickness greater than the middle thickness.

In some embodiments, the technology described herein comprises a golf club head comprising a striking face having a face center, a crown, a sole opposite the crown, a heel, a toe opposite the heel, and a hosel adjacent the heel and configured to couple the golf club head to a shaft, wherein the striking face further comprises a variable face thickness profile having a substantially planar front surface and a non-planar back surface, wherein an X-axis is defined as a horizontal axis tangent to the face center of the striking face and having a positive direction toward the heel of the golf club head, a Y-axis is a vertical axis perpendicular to the X-axis and having a positive direction toward the crown of the golf club head, a Z-axis is a vertical axis perpendicular to both the X-axis and the Y-axis and having a positive direction toward the front of the golf club head, the origins of the X-axis, the Y-axis, and the Z-axis are located at a center of gravity (CG) of the golf club head, and wherein the variable face thickness profile of the striking face comprises a central region having a constant thickness, a heel region having a thickness that decreases from an upper toe portion to a lower heel portion, and an upper heel portion. A golf club head comprising a toe area whose thickness decreases from the lower portion to the toe area.

In some embodiments, the technology described herein comprises a golf club head comprising a striking face having a face center, a crown, a sole opposite the crown, a heel, a toe opposite the heel, and a hosel adjacent the heel and configured to couple the golf club head to a shaft, wherein the striking face further comprises a variable face thickness profile having a substantially planar front surface and a non-planar back surface, wherein an X-axis is defined as a horizontal axis tangent to the face center of the striking face and having a positive direction toward the heel of the golf club head, a Y-axis is a vertical axis perpendicular to the X-axis and having a positive direction toward the crown of the golf club head, a Z-axis is perpendicular to both the X-axis and the Y-axis and having a positive direction toward the front of the golf club head, the origins of the X-axis, the Y-axis, and the Z-axis are located at a center of gravity (CG) of the golf club head, and wherein the variable face thickness profile of the striking face comprises a central region that is wider near a top portion of the striking face and narrows toward a lower sole portion of the striking face, a heel region, and It relates to a golf club head that includes more of the toe area.

In some aspects, the technology described herein comprises a golf club head comprising a striking face having a face center, a crown, a sole opposite the crown, a heel, a toe opposite the heel, and a hosel adjacent the heel and configured to couple the golf club head to a shaft, wherein the striking face further comprises a sole extension adjacent the sole, the sole extension further comprising an initial front portion having an initial front thickness, a middle portion having an intermediate thickness, and a terminal portion having a terminal thickness, the striking face further comprising a variable face thickness profile having a substantially planar front portion and a non-planar back portion, wherein an X-axis is defined as a horizontal axis tangent to the face center of the striking face and having a positive direction toward the heel of the golf club head, a Y-axis is a vertical axis orthogonal to the X-axis and having a positive direction toward the crown of the golf club head, a Z-axis is orthogonal to both the X-axis and the Y-axis and having a positive direction toward the front of the golf club head, and wherein the origins of the X-axis, the Y-axis, and the Z-axis are centered on the golf club head. A golf club head is provided, wherein the variable face thickness profile of the striking face is located at the center of gravity (CG) of the head, and further includes a central region, a heel region, and a toe region that are wider near the top portion of the striking face and narrower toward the lower sole portion of the striking face.

These and other features, aspects and advantages of the present invention will be better understood with reference to the drawings, description and claims below.

The aforementioned features and advantages of the present invention, along with other features and advantages, will become apparent from the following description of the present invention, illustrated in the accompanying drawings. The accompanying drawings, incorporated herein and forming a part of this specification, are intended to illustrate the principles of the present invention and to enable those skilled in the art to make and use the invention.
Figure 1 of the attached drawings is a perspective view of a golf club head according to an exemplary embodiment of the present invention.
Figure 2 of the attached drawing is a crown side view of a golf club head according to one embodiment of the present invention.
Figure 3 of the attached drawing is a side view of the face of a golf club head according to one embodiment of the present invention.
FIG. 4 of the attached drawings is a toe-side cross-sectional view taken along a vertical plane passing through the center of the face of a golf club head according to one embodiment of the present invention and extending along the Z-axis.
Among the attached drawings , FIG. 5a is a perspective view of the sole of a golf club head according to one embodiment of the present invention.
Among the attached drawings , FIG. 5b is a perspective view of the sole of a golf club head according to an alternative embodiment of the present invention.
Figure 6 of the attached drawings is an exploded perspective view of a heel side of a golf club head according to an alternative embodiment of the present invention.
Figure 7 of the attached drawings is an exploded perspective view of the toe side of a golf club head according to an alternative embodiment of the present invention.
Figure 8 of the attached drawings is a cross-sectional view of a golf club head according to an alternative embodiment of the present invention.
Figure 9 of the attached drawings is an exploded perspective view of a heel side of a golf club head according to an alternative embodiment of the present invention.
Figure 10 of the attached drawings is a toe side exploded perspective view of a golf club head according to an alternative embodiment of the present invention.
Figure 11 of the attached drawings is a cross-sectional view of a golf club head according to an alternative embodiment of the present invention.
Figure 12 of the attached drawings is an exploded view of the heel side of a golf club head according to another alternative embodiment of the present invention.
FIG. 13 of the attached drawings is a heel side perspective view of a striking face according to another alternative embodiment of the present invention.
Figure 14 of the attached drawings is a rear view of a striking face according to another alternative embodiment of the present invention.
FIG. 15 of the attached drawings is a cross-sectional view taken along the cross-sectional line ( A-A' ) shown in FIG. 14 of a striking face according to another alternative embodiment of the present invention.
Figure 16 of the attached drawings is a rear view of a striking face of a golf club head according to an alternative embodiment of the present invention.
Figure 17 of the attached drawings is a cross-sectional view of an iron-shaped golf club head according to an alternative embodiment of the present invention.
Figure 18 of the attached drawings is an enlarged cross-sectional view of a sole portion of an iron-type golf club head according to an alternative embodiment of the present invention.
Figure 19 of the attached drawings is a rear view of a striking face of a golf club head according to another alternative embodiment of the present invention.
Figure 20 of the attached drawings is a rear view of a striking face of a golf club head according to another alternative embodiment of the present invention.

The following detailed description describes the best mode currently contemplated for carrying out the invention. The description is intended solely to illustrate the general principles of the invention and should not be construed in a limiting sense, as the scope of the invention is best defined by the appended claims.

Various inventive features are described below, each of which may be used independently or in combination with other features. However, any single inventive feature may not address some or all of the aforementioned problems, or may address only one of the aforementioned problems. Furthermore, one or more of the aforementioned problems may not be completely resolved by any of the features described below.

Before beginning a discussion of the golf club head ( 100 ) of the present invention and its performance criteria, it is important to note that the discussion below is based on a coordinate system ( 101 ) and measurement axes that are critical to the proper evaluation of the performance parameters detailed below. Therefore, while the specific designations given for the measurements below are important to understanding the present invention, it is important to recognize that the nomenclature should not be viewed without context. Rather, the significance of the numbers presented below should be understood in the context of how the coordinate system relates to the golf club head itself. To provide sufficient information to avoid ambiguity, each drawing below that references the golf club head ( 100 ) is provided with a reference coordinate system.

In accordance with the foregoing, and to establish a reference coordinate system for the subsequent discussion, FIG. 1 of the accompanying drawings illustrates a coordinate system ( 101 ) that will be used to define various measurements and performance metrics for the present invention. The X-axis, as used in the present discussion, refers to an axis that is parallel to the striking face in the heel-to-toe direction. The Y-axis, as used in the present discussion, refers to a vertical axis that runs through the club in the crown-to-sole direction. The Z-axis, as used in the present discussion, refers to a horizontal axis that is parallel to the front-to-back direction. Alternatively, the X-axis may be defined as a horizontal axis that is tangent to the geometric center of the striking face and has a positive direction toward the heel of the golf club head, the Y-axis may be a vertical axis that is orthogonal to the X-axis and has a positive direction toward the crown of the golf club head, and the Z-axis may be said to be orthogonal to both the X-axis and the Y-axis and has a positive direction toward the front of the golf club head. The XYZ coordinate system ( 101 ) described above applies equally to all subsequent discussions.

FIG. 1 of the attached drawings is a perspective view of a golf club head ( 100 ) according to one embodiment of the present invention. In this perspective view illustrated in FIG. 1 , the golf club head ( 100 ) may not appear significantly different from other golf club heads, but the drawings and discussion therein that follow will show that the specific dimensions and material properties of this golf club head ( 100 ) enable it to achieve unique performance characteristics consistent with the present invention. FIG . 1 shows a golf club head ( 100 ) having a striking face ( 120 ), a crown ( 106 ), a sole ( 108 ) opposite the crown ( 106 ), a heel ( 104 ), a toe ( 102 ) opposite the heel ( 104 ), a hosel ( 124 ) proximate and adjacent the heel and for coupling the golf club head ( 100 ) to a shaft ( not shown), and a skirt ( 112 ) connecting the crown ( 106 ) and the sole ( 108 ) and extending from the heel ( 104 ) adjacent the striking face ( 120 ) to the toe ( 102 ) adjacent the striking face ( 120 ) . The striking face ( 120 ) has a face center ( 122 ). The face center ( 122 ) illustrated in this specification and referred to by the present invention relates to the geometric center of the striking face ( 120 ) of the golf club head ( 100 ) as measured by the face center template provided by the USGA as is known to those of ordinary skill in the art of golf club technology.

In this embodiment of the present invention, the golf club head ( 100 ), particularly the striking face ( 120 ), crown ( 106 ), sole ( 108 ), skirt ( 112 ), toe ( 102 ), heel ( 104 ), and hosel ( 124 ), can be formed from a steel alloy having a density of generally from about 7.75 g/cc to about 8.05 g/cc. Preferably, the golf club head ( 100 ) is formed through a casting process as is known in the art. It is also within the scope and spirit of the present invention for at least a portion of the golf club head ( 100 ) to be formed through other known processes including stamping, forging, and rolling.

It is within the scope of the present invention that the striking face ( 120 ), crown ( 106 ), sole ( 108 ), skirt ( 112 ), toe ( 102 ), heel ( 104 ) and hosel ( 124 ) are formed from a steel alloy having an overall density of about 7.75 g/cc to about 8.05 g/cc.

It is within the scope and spirit of the present invention that the striking face ( 120 ) be formed integrally with other portions of the golf club head ( 100 ), or alternatively, formed as a separate component and later joined to other portions of the golf club head (100). When the striking face ( 120 ) is formed as a separate component, it may be formed of high-strength steel and joined to the golf club head ( 100 ) by any suitable means, including welding, brazing, adhesives, and mechanical fastening mechanisms. Exemplary high-strength steel materials for forming the striking face ( 120 ) include, but are not limited to, custom 465 stainless steel, custom 475 stainless steel, 300 stainless steel, and 301 stainless steel.

The volume of the golf club head ( 100 ) may generally be from about 100 cc to about 200 cc, more preferably from about 120 cc to about 190 cc, and most preferably from about 140 cc to about 185 cc.

The total mass of the golf club head ( 100 ) may generally be from about 175 g to about 275 g, more preferably from about 190 g to about 250 g, and most preferably from about 200 g to about 225 g.

FIG. 2 is a crown side view of a golf club head ( 100 ). In order to illustrate more specific features of the golf club head ( 100 ), FIG . 2 of the accompanying drawings is provided for the purpose of providing additional insight into some specific characteristics of the golf club head ( 100 ) that are important for quantifying improved performance. FIG. 2 of the accompanying drawings shows the location of the CG ( 110 ) along the XZ plane of the coordinate system ( 101 ). While the specifics of the CG ( 110 ) location will be discussed in more detail in connection with the inertial characteristics of the golf club head ( 100 ), generally speaking, the golf club head ( 100 ) of the present invention has a CG ( 110 ) location strategically positioned within the golf club head ( 100 ) to produce the most advantageous results.

More specifically, in the present exemplary embodiment of the present invention, CG ( 110 ) is positioned at a rearward distance CG-C ( 114 ) from the shaft axis ( 115 ) extending along the XY plane of generally about 9 mm to about 16 mm, more preferably about 10 mm to about 15 mm, and most preferably about 11 mm to about 14 mm, all of which are measured rearward from the shaft axis ( 115 ) along the Z-axis represented by the coordinate system ( 101 ).

It should be noted that the strategic position of the CG ( 110 ) rearward along the Z-axis is very important for the proper functioning of the golf club head ( 100 ) of the present invention. If the CG ( 110 ) position is too forward, the inertia value of the golf club head ( 100 ) may decrease, and also suboptimal backspin may be generated when contacting the golf ball, which may result in undesirable results. However, conversely, if the CG ( 110 ) position is too rearward, the golf club head ( 100 ) may generate too much spin, which may not result in desirable results. Therefore, it can be seen that the critical point of the CG ( 110 ) position rearward of the shaft axis ( 115 ) along the Z-axis requires a delicate balance within a very specific value range, and any deviation from that range may seriously impair the performance of the golf club head ( 100 ).

FIG. 3 of the accompanying drawings is a face side view of a golf club head ( 100 ). FIG. 3 shows several additional dimensional measurements that are important for the proper functioning of the present invention. Specifically, in addition to illustrating the basic components of the golf club head ( 100 ) previously illustrated, FIG. 3 now introduces another measurement of the location of the CG ( 110 ) from the ground ( G ) along the XY plane represented by the coordinate system ( 101 ). More specifically, FIG. 3 shows the CG ( 110 ) measurement, which is the distance measured vertically along the Y-axis from the ground ( G ) to the CG ( 110 ), and for the purposes of this discussion is referred to as CG-Yg ( 116 ). The CG-Yg ( 116 ) of the golf club head ( 100 ) may generally be less than about 16.0 mm, more preferably about 11.0 mm to about 15.0 mm, and most preferably about 12.0 mm to about 14.5 mm.

In addition to illustrating the very important CG-Yg ( 116 ) measurement of the golf club head ( 100 ), FIG. 3 of the accompanying drawings also illustrates a peak crown height ( 117 ) measurement, which is the vertical distance from the ground ( G ) to the apex of the crown ( 106 ) along the Y-axis when the golf club head ( 100 ) is in the normal address position. The peak crown height ( 117 ) measurement can generally be greater than about 35.0 mm, preferably about 36.0 mm to about 43.0 mm, and most preferably about 37.0 mm to about 41.0 mm.

FIG. 3 of the attached drawings also illustrates a ground-top radius measurement ( 118 ), which is the vertical distance from the ground ( G ) along the Y-axis to the point where the striking face ( 120 ) transitions to the crown ( 106 ). More specifically, the ground-top radius measurement ( 118 ) is the vertical distance from the ground ( G ) along the Y-axis to the point where the golf club head (100) deviates from the roll radius of the striking face ( 120 ). The ground-top radius measurement ( 118 ) is the vertical distance from the face center (122) along the Y-axis to the point where the golf club head ( 100 ) transitions to the crown ( 106 ). It is within the scope and content of the present invention that the ground-top radius measurement (118) is taken at the highest point directly above or on the striking face ( 120 ). Preferably, the ground-top radius measurement ( 118 ) is taken directly above the face center ( 122 ). The ground-top radius measurement ( 118 ) can generally be at least about 31.0 mm, more preferably from about 31.0 mm to about 37.0 mm, and most preferably from about 33.0 mm to about 35.0 mm.

Figure 3 of the attached drawing also shows the measured value of ΔYccg ( 119 ), which is the vertical distance from CG ( 110 ) to the apex of the crown ( 106 ) along the Y-axis. That is, the ΔYccg measurement ( 119 ) is the difference between the peak crown height ( 117 ) measurement and the CG-Yg ( 116 ) measurement. The ΔYccg ( 119 ) measurement is discussed in more detail below.

Now that the CG ( 110 ) location of the golf club head ( 100 ) has been defined, another important feature of the present invention relating to the moment of inertia (MOI) of the golf club head ( 100 ) can be described in more detail. The MOI of a golf club head generally represents the ability of the golf club head to resist twisting when the golf club head impacts an object at a location that is not aligned with the aforementioned CG location. More specifically, the MOI of a golf club head relates to the ability of the golf club head to resist twisting about the CG location.

As is well known in the art, the MOI of a golf club head ( 100 ) can generally be decomposed into several unique components relating to the ability of the golf club head ( 100 ) to resist rotation about the CG ( 110 ) location along different axes, three of which have their origins coincident with the CG ( 110 ) location of the golf club head ( 100 ). The three rotational axes about which the MOI is generally referenced are coincident with a coordinate system ( 101 ) depicted throughout the drawings, wherein MOI-X is measured about the X-axis passing through the CG ( 110 ), MOI-Y is measured about the Y-axis passing through the CG ( 110 ), and MOI-Z is measured about the Z-axis passing through the CG ( 110 ).

The MOI-X of the golf club head ( 100 ) of the present invention is generally greater than about 80 kg-mm ² , more preferably about 90 kg-mm ² to about 140 kg-mm ² , and most preferably about 100 kg-mm ² It may be about 130 kg-mm ² , all of which are within the scope and content of the present invention.

The MOI-Y of the golf club head ( 100 ) of the present invention may generally be greater than about 220 kg-mm ² , more preferably greater than about 230 kg-mm ² , and most preferably greater than about 240 kg-mm ² , all of which are within the scope and content of the present invention. In other words, the golf club head ( 100 ) of the present invention can generally have a high MOI-Y value while maintaining a relatively low CG ( 110 ) position.

The MOI-Z of the golf club head ( 100 ) of the present invention may generally be greater than about 160 kg-mm ² , more preferably from about 160 kg-mm ² to about 220 kg-mm ² , and most preferably from about 170 kg-mm ² to about 210 kg-mm ² , all of which are within the scope and content of the present invention.

While the MOI values discussed above are not necessarily new in the field of golf club head ( 100 ) design, the ability to maintain these values, particularly the relative values of CG-Yg ( 116 ) and CG-C ( 114 ), while setting the CG ( 110 ) location as described above, is what makes the present invention so unique. The present invention lowers the CG of a steel golf club head than ever before while maintaining dimensions such as the volume, peak crown height, and ground-to-top radius height of a conventional fairway wood.

FIG. 4 is a cross-sectional view of the toe side taken along a vertical plane passing through the center of the face ( 122 ) and extending along the Z-axis. As described below, FIG. 4 illustrates several additional important features of the present invention.

Now referring to FIG. 4 , additional inventive features of the present invention are Some of the dimensions of the golf club head ( 100 ) are more clearly illustrated. According to an exemplary embodiment of the present invention, the minimum crown thickness ( Tc ) of the crown ( 106 ) is thinner than the thickness of a conventional cast steel crown, which is generally greater than 0.6 mm. According to a current exemplary embodiment, the minimum crown thickness ( Tc ) of the crown ( 106 ) is preferably from about 0.3 mm to about 0.6 mm, more preferably from about 0.35 mm to about 0.5 mm, and most preferably about 0.4 mm.

Additionally, a portion of the crown may have a substantially constant thickness within +/- 10% of the minimum crown thickness ( Tc ) of the crown ( 106 ). For the purposes of this discussion, the surface area of the crown ( 106 ) is defined as that portion of the golf club head ( 100 ) excluding the hosel ( 124 ) that is visible directly above the golf club head ( 100 ) when the golf club head ( 100 ) is in the normal address position. According to one embodiment of the present invention, at least about 40% of the total surface area of the crown ( 106 ) can have a substantially constant thickness within +/- 10% of the minimum crown thickness ( Tc ), preferably at least about 60% of the total surface area of the crown ( 106 ) can have a substantially constant thickness within +/- 10% of the minimum crown thickness ( Tc ), and most preferably at least about 75% of the total surface area of the crown ( 106 ) can have a substantially constant thickness within +/- 10% of the minimum crown thickness ( Tc ).

By reducing the thickness of the crown ( 106 ) as described above, the total mass of the crown ( 106 ) can be reduced. The mass savings associated with reducing the thickness of the crown ( 106 ) can be redistributed to any mass throughout the golf club head ( 100 ), such as any mass within and/or near the sole ( 108 ). The golf club head ( 100 ) of the present invention having the crown ( 106 ) as described above can exhibit a CG-Yg ( 116 ) measurement that is at least 0.3 mm less than a conventional golf club head having a minimum crown thickness greater than 0.6 mm. While a 0.3 mm reduction in CG-Yg( 116 ) measurement may seem trivial at first glance, the present invention utilizes several inventive features to produce a CG-Yg( 116 ) measurement smaller than any other known golf club head formed of steel and having conventional dimensions, as described above.

FIG. 4 illustrates another feature that further facilitates lowering the CG-Yg( 116 ) measurement of a golf club head( 100 ). It is well known that a striking face has different thicknesses at different points on the striking face, which is referred to as variable face thickness (VFT). In an exemplary embodiment of the present invention, the maximum face thickness ( Tf ) occurs near the face center ( 122 ) and is preferably less than about 2.0 mm, more preferably less than about 1.95 mm, and most preferably about 1.9 mm. Typically, the maximum face thickness ( Tf ) of a steel striking face is greater than about 2.0 mm. A golf club head( 100 ) of the present invention having a striking face( 120 ) as described above can exhibit a CG-Yg( 116 ) measurement that is at least 0.1 mm lower than a conventional golf club head having a maximum face thickness ( Tf ) of at least 2.0 mm. The maximum face thickness ( Tf ) is the distance between the outer surface and the inner surface of the striking face measured perpendicular to the loft plane ( L ), where the loft plane ( L ) is a plane tangent to the face center ( 122 ) of the striking face ( 120 ). While a 0.1 mm reduction in CG-Yg ( 116 ) may appear insignificant at first glance, the present invention utilizes several inventive features to achieve a CG-Yg ( 116 ) smaller than any other known golf club head formed of steel and having conventional dimensions, as described above.

Figure 4 also shows the loft angle (θ), which is the angle between the loft plane ( L ) and the XY plane. Preferably, the loft angle (θ) is between about 12 degrees and about 25 degrees.

FIG. 4 also shows a unique hosel ( 124 ) structure for use with an adjustable shaft sleeve (not shown) as is known in the art. The hosel ( 124 ) is configured to adjustably couple a golf club head ( 100 ) to a shaft (not shown). The hosel ( 124 ) includes an upper hosel portion ( 124A ) proximate the crown ( 106 ) and a lower hosel portion ( 124B ) proximate the sole ( 108 ). The upper hosel portion ( 124A ) is configured to receive an adjustable shaft sleeve (not shown) to adjust the orientation (lie, loft, and face angle) of the golf club head ( 100 ). The lower hosel portion ( 124B ) is configured to adjust the orientation (lie, loft, and face angle) of the golf club head ( 100 ). Likewise, it is configured to accommodate a fastening mechanism (not shown) for coupling a shaft sleeve (not shown) to a golf club head ( 100 ). Unlike conventional structures, a portion of the hosel ( 124 ) between the upper hosel portion ( 124A ) and the lower hosel portion ( 124B ) is open to the interior of the golf club head ( 100 ).

As compared to a conventional hosel as described above, the total mass of the hosel ( 124 ), including the individual upper hosel portion ( 124A ) and the individual lower hosel portion ( 124B ), can be reduced, particularly that portion of the mass of the hosel ( 124 ) above the CG ( 110 ) location. The mass savings associated with the hosel ( 124 ) can be redistributed to any mass throughout the golf club head ( 100 ) as compared to a conventional hosel design, such as any mass within and/or near the sole ( 108 ). A golf club head ( 100 ) of the present invention having a hosel ( 124 ) as described above can exhibit a CG-Yg ( 116 ) measurement that is at least 0.35 mm lower than a conventional golf club head having a conventional hosel configured to receive a conventional adjustable shaft sleeve. While a 0.35 mm reduction in CG-Yg( 116 ) measurement as described above may seem trivial at first glance, the present invention utilizes several inventive features to produce a CG-Yg( 116 ) measurement smaller than any other known golf club head formed of steel and having conventional dimensions as described above.

FIG. 4 also illustrates an optional weight pocket ( 130 ) positioned proximate the sole ( 108 ) of the golf club head ( 100 ). The weight pocket ( 130 ) is configured to receive a weight member (not shown) therein. The structure of the weight member is not critical to the present invention, and it should be understood that the weight member may take the form of known structures as well as variations of known structures. The weight member may be formed of any number of materials having a density less than, equal to, or greater than that of the remainder of the golf club head ( 100 ). Preferably, the weight member may be formed of a steel alloy having substantially the same density as the remainder of the golf club head ( 100 ). Alternatively, the weight member may comprise a material having a density greater than that of the steel portion of the golf club head ( 100 ), such as at least one of tungsten, molybdenum, tantalum, hafnium, and niobium. Additionally, it is also within the scope of the present invention that the weight member comprises a material having a lower density than the steel portion of the golf club head ( 100 ), such as at least one of titanium, aluminum, plastic, and composite. The mass saved by reducing the minimum thickness of the crown ( 106 ), reducing the maximum thickness of the striking face ( 120 ), and modifying the structure of the hosel ( 124 ) to open into the interior of the golf club head ( 100 ) can be distributed as any mass within and/or near the sole ( 108 ). For example, any mass can be distributed within the sole ( 108 ), the weight member, or within any portion of the golf club head ( 100 ) below the CG ( 110 ) to minimize the CG-Yg ( 116 ) measurement while maintaining the traditional dimensions and other important inertia values of the golf club head ( 100 ).

As illustrated in FIG. 4 , a significant portion of the sole ( 108 ) has a substantially constant thickness. Additionally, a portion of the sole ( 108 ) behind the weight pocket ( 130 ) has a substantially constant thickness, which is substantially equal to the maximum sole thickness ( Ts ). Note that for purposes of identifying the maximum sole thickness ( Ts ), the portion of the sole ( 108 ) adjacent to the weight pocket ( 130 ) and the portion of the sole within about 10 mm from the skirt ( 112 ) are not considered. The maximum sole thickness ( Ts ) is preferably about 1.6 mm or greater, more preferably about 1.8 mm or greater, and most preferably about 1.9 mm or greater.

According to one embodiment of the present invention, at least 30% of the sole ( 108 ) has a thickness within +/- 10% of the maximum sole thickness ( Ts ), more preferably at least 40% of the sole ( 108 ) has a thickness within +/- 10% of the maximum sole thickness ( Ts ), and most preferably at least 50% of the sole ( 108 ) has a thickness within +/- 10% of the maximum sole thickness ( Ts ).

It should be noted that the maximum sole thickness ( Ts ) at this time does not encompass the overall effect of the mass concentrated within and/or near the sole ( 108 ) since it does not, by definition, take into account the weight pocket (130), the weight member, or any additional elements required to secure the weight member within the weight pocket ( 130 ).

To better illustrate these features, FIGS. 5A and 5B are provided. FIG. 5A shows a sole ( 108 ) separated from the remainder of a golf club head ( 100 ), and FIG. 5B shows a sole ( 208 ) according to an alternative embodiment of the present invention.

Referring first to FIG. 5A , the sole ( 108 ) is depicted separately from the remainder of the golf club head ( 100 ). From this perspective, it is much easier to see that the weight pocket ( 130 ), the weight member (not shown), and the surrounding structure have the potential to concentrate mass within and/or near the sole ( 108 ) to bring the CG ( 110 ) closer to the ground. It is also apparent that describing a portion of the sole ( 108 ) as having a substantially constant thickness does not paint the full picture of how the sole ( 108 ) contributes to bringing the CG ( 110 ) closer to the ground. In particular, describing the sole ( 108 ) in this manner does not encompass the influence of the weight member (not shown) or portions of the sole ( 108 ) that define and/or support the weight pocket ( 130 ).

It should be noted that defining that portion of the golf club head ( 100 ) that defines the sole ( 108 ) is not as simple as identifying the bottom of the golf club head ( 100 ). For example, the sole ( 108 ) may be defined as the entire golf club head ( 100 ) that is visible directly below the golf club head ( 100 ) when the golf club head ( 100 ) is in its normal address position. Alternatively, the sole ( 108 ) may be defined as the portion of the golf club head ( 100 ) that is bounded by the lower portion of the skirt ( 112 ) and the lower portion of the striking face ( 120 ).

To quantify the influence of the sole ( 108 ) according to an exemplary embodiment of the present invention in a meaningful and simple manner, the sole ( 108 ) is generally located at the center of the bottom of the golf club head ( 100 ) and is approximately 25 cm ² As part of a golf club head ( 100 ) having an external surface area of about 35 cm ² The total mass of the sole ( 108 ) including the weight pocket ( 130 ) and the weight member (not shown) therein may be from about 50 g to about 80 g.

FIG. 5b includes a weight pocket ( 130 ) that accommodates a weight member (not shown) having the same density as the golf club head ( 100 ). It shows a sole ( 208 ) with the same peripheral shape, surface area and total mass as the sole ( 108 ).

Sol ( 208 ) is the same peripheral shape as Sol ( 208 ), about 25 cm ² It is configured to be interchangeable with the sole ( 108 ) in that it has the same external surface area of about 35 cm ² and the same mass of about 50 g to about 80 g. However, unlike the sole ( 108 ), the sole ( 208 ) does not include a weight pocket, and therefore the sole ( 208 ) is thicker than the sole ( 108 ). The increased thickness of the sole ( 208 ) helps to quantify the overall effect the sole ( 208 ) has on the CG ( 110 ) location.

According to an embodiment of the present invention, the sole ( 208 ) can have an average effective sole thickness ( Tsa ) of from about 2.4 mm to about 3.2 mm, preferably from about 2.5 mm to about 3.1 mm, and most preferably from about 2.6 mm to about 3.0 mm. The average effective sole thickness ( Tsa ) is determined by dividing the total mass of the sole ( 208 ) by the outer surface area of the sole ( 208 ). Thus, the average effective sole thickness ( Tsa ) is a constant thickness of the sole ( 208 ), but the average effective sole thickness ( Tsa ) takes into account the mass contributed by the weight pocket ( 130 ) and any weight members (not shown) accommodated therein. Therefore, since the total mass and external surface area of the sole ( 108 ) and the sole ( 208 ) are both the same, it can be said that the sole ( 108 ) has the same average effective sole thickness ( Tsa ) as the sole ( 208 ). In addition, the sole ( 208 ) is configured to have the same effect on the CG ( 110 ) location and MOI of the golf club head ( 100 ) as the sole ( 108 ).

Due to the combined effects on the CG-Yg( 116 ) measurements associated with the aforementioned reduction in minimum thickness of the crown( 106 ), the reduction in maximum thickness of the striking face(120), the structural change of the hosel( 124 ) to open into the interior of the golf club head( 100 ), and the reduced mass distribution within and/or near the sole(108 , 208 ) , the CG-Yg(116 ) measurements About 1.5 mm to about 2.0 mm lower than the known steel golf club head of the conventional dimensions presented above.

It is important to note here that the aforementioned low CG-Yg( 116 ) measurements alone cannot accurately describe and explain the present invention. This is because golf club heads with small volume or excessively shallow dimensions (low peak crown height and/or low face height) may inherently have low CG-Yg measurements. Therefore, it is important to recognize that the present invention is premised on the interrelationship between the different values achieved by the CG-C, MOI, volume, and height measurements in relation to the aforementioned CG-Yg( 116 ) measurements.

Another way to understand the impact of the aforementioned mass savings is to look at the percentage of the golf club head's ( 100 ) mass that is concentrated in the lower portion of the golf club head ( 100 ). Referring again to FIG. 3 , it is useful to consider the mass distribution within the golf club head ( 100 ) as a percentage of the peak crown height ( 117 ) measurement.

The mass of the golf club head ( 100 ) below the XZ plane, which is set at a vertical height equal to 25% of the peak crown height ( 117 ) measured from the ground ( G ), is preferably greater than about 45% of the total mass of the golf club head (100 ) , more preferably greater than about 48% of the total mass of the golf club head (100), and most preferably greater than about 50% of the total mass of the golf club head ( 100 ).

The mass of the golf club head ( 100 ) below the XZ plane, which is set at a vertical height equal to 20% of the peak crown height ( 117 ) measured from the ground ( G ), is preferably greater than about 38% of the total mass of the golf club head (100 ) , more preferably greater than about 41% of the total mass of the golf club head (100), and most preferably greater than about 43% of the total mass of the golf club head ( 100 ).

The mass of the golf club head ( 100 ) below the XZ plane, which is set at a vertical height equal to 15% of the peak crown height ( 117 ) measured from the ground ( G ), is preferably greater than about 27 % of the total mass of the golf club head ( 100 ), more preferably greater than about 30% of the total mass of the golf club head (100), and most preferably greater than about 32% of the total mass of the golf club head ( 100 ).

The mass of the golf club head ( 100 ) below the XZ plane, which is set at a vertical height equal to 10% of the peak crown height ( 117 ) measured from the ground ( G ), is preferably greater than about 12% of the total mass of the golf club head (100 ) , more preferably greater than about 15% of the total mass of the golf club head (100), and most preferably greater than about 17% of the total mass of the golf club head ( 100 ).

By concentrating most of the mass of the golf club head ( 100 ) toward the sole ( 108 ) of the golf club head ( 100 ), CG-Yg ( 116 ) can be reduced as described above.

At this time, it is worth discussing the unique relationship of the present invention between the mass of the sole ( 108, 208 ) and the outer surface area of the sole (108 , 208 ) to better understand how the golf club head ( 100 ) achieves the aforementioned inertial and dimensional characteristics. The sole mass to sole surface area ratio helps to quantify the golf club head ( 100 ) of the present invention as shown in the equation below. In one exemplary embodiment of the present invention, the sole mass to sole surface area ratio of the sole ( 108 ) and sole ( 208 ) is at least about 2.0 g/cm ² , more preferably at least about 2.1 g/cm ² , and most preferably at least about 2.2 g/cm ² .

Another relationship unique to the present invention is the relationship between the peak crown height ( 117 ) measurement and the CG-Yg ( 116 ) measurement. This ratio, called the weighted peak crown height to CG-Yg ratio, helps to quantify the golf club head ( 100 ) of the present invention as shown in the equation below. The weighted peak crown height to CG-Yg ratio is the product of the cosine of the loft angle (θ) and the ratio between the peak crown height ( 117 ) measurement and the CG-Yg ( 116 ) measurement. In one exemplary embodiment, the weighted peak crown height to CG-Yg ratio of the golf club head ( 100 ) The ratio is about 2.4 or greater, preferably about 2.5 or greater, and most preferably about 2.6 or greater.

As previously discussed, the weighted peak crown height to CG-Yg ratio is critical to the present invention because it combines the performance benefits of a low CG ( 110 ) with the shape of a traditional golf club head ( 100 ). While it is possible to lower the CG ( 110 ) using known techniques, these known techniques require the use of exotic materials and/or modifications to the traditional golf club head shape, such as reducing the peak crown height or ground-to-top radius of the golf club head.

Another relationship unique to the present invention relates to the difference between the peak crown height ( 117 ) measurement and the CG-Yg ( 116 ). The vertical distance between the peak crown height ( 117 ) measurement and the CG-Yg ( 116 ), ΔYccg ( 119 ), helps to quantify the golf club head ( 100 ) of the present invention as shown in the equation below. In one exemplary embodiment, the ΔYccg ( 119 ) of the golf club head ( 100 ) is about 22.0 mm to about 28.0 mm, preferably about 23.0 mm to about 26.0 mm, and most preferably about 24.0 mm to about 25.0 mm.

As previously mentioned, the ΔYccg is very important to the present invention because it combines the performance benefits of a low CG ( 110 ) with the shape of a traditional golf club head ( 100 ). While it is possible to lower the CG ( 110 ) using known techniques, these known techniques require the use of exotic materials and/or modifications to the traditional golf club head shape, such as reducing the peak crown height or ground-to-top radius of the golf club head.

Another relationship unique to the present invention is the relationship between the minimum crown thickness ( Tc ) and the maximum sole thickness ( Ts ). The minimum crown thickness ( Tc ) as defined herein refers to the portion of the crown ( 106 ) of the golf club head having the thinnest wall thickness, which may include any cutouts that may exist in the crown ( 106 ) portion. Meanwhile, the maximum sole thickness ( Ts ) as defined herein refers to the portion of the sole ( 108 ) having the thickest wall thickness, which may include any sole geometry, but excluding any ribs and/or portions of the sole associated with external weighting features that may create the visual illusion of a thickened sole ( 108 ). The maximum sole thickness to minimum crown thickness ratio helps to quantify the golf club head ( 100 ) of the present invention, as shown in the equation below. In one exemplary embodiment of the present invention, the maximum sole thickness to minimum crown thickness ratio is at least about 4.0, preferably at least about 4.5, and most preferably at least about 4.75.

As previously discussed, the maximum sole thickness to minimum crown thickness ratio is critical to the present invention because it combines the performance benefits of a low CG ( 110 ) with the all-steel structure of the golf club head ( 100 ). While it is possible to similarly lower CG ( 110 ) using known techniques, these known techniques require the use of exotic materials, such as forming the crown from a different material, such as titanium or a composite.

Another relationship unique to the present invention is the relationship between the average effective sole thickness ( Tsa ) and the minimum crown thickness ( Tc ). The ratio of the average effective sole thickness to the minimum crown thickness helps to quantify the golf club head ( 100 ) of the present invention, as shown in the equation below. In one exemplary embodiment, the ratio of the average effective sole thickness to the minimum crown thickness is from about 3.5 to about 9.0, preferably from about 4.5 to about 8.5, and most preferably from about 5.0 to about 8.0.

As previously discussed, the average effective sole thickness to minimum crown thickness ratio is critical to the present invention because it combines the performance benefits of a low CG ( 110 ) with the all-steel structure of the golf club head ( 100 ). While it is possible to similarly lower the CG ( 110 ) close to the ground using known techniques, these known techniques require the use of exotic materials, such as forming the crown from different materials such as titanium or composites.

Except in the operating examples, or unless otherwise explicitly stated, all numerical ranges, quantities, values, and percentages within the preceding portions of this specification, such as amounts of material, moments of inertia, locations of centers of gravity, lofts, draft angles, various performance ratios, and the like, are to be read as if preceded by the word "about" even if the term "about" does not explicitly appear in the value, quantity, or range. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

According to another embodiment of the present invention, the crown ( 106 ) may be formed of a lightweight material having a lower density than steel. For example, the crown ( 106 ) may be formed of a composite material or a titanium alloy. As described above, the composite material The golf club head ( 100 ) of the present invention having a formed crown ( 106 ) can exhibit a CG-Yg( 116 ) measurement that is at least 0.20 mm smaller than a conventional golf club head having an all-steel structure. While a 0.20 mm reduction in the CG-Yg( 116 ) measurement may appear trivial at first glance, the present invention utilizes several inventive features to achieve a CG-Yg( 116 ) measurement that is smaller than any other known golf club head having conventional dimensions, as described above.

FIG. 6 of the attached drawings is an exploded view of a golf club head ( 600 ) according to an alternative embodiment of the present invention, wherein the striking face ( 620 ) is an L-cup shape having a sole return ( 623 ) rather than a face insert as shown in the previous embodiment. Having an L-cup shaped striking face can further enhance the performance of the golf club head ( 600 ) by not only improving the center of gravity location of the golf club head ( 600 ) within the aforementioned range, but also by providing greater structural integrity to the leading edge of the golf club head ( 600 ) itself. Increasing the structural integrity of the golf club head ( 600 ) at the leading edge can further enhance the performance of the golf club head ( 600 ) by reducing spin on shots struck against the striking face ( 620 ), a phenomenon commonly seen in fairway woods such as the present invention.

The striking face ( 620 ) may be attached to the body portion ( 640 ) of the golf club head ( 600 ) through the front opening ( 621 ) (shown in FIG. 7 ) via traditional attachment techniques such as welding, although in alternative embodiments of the present invention other attachment techniques may also be used, such as brazing, bonding or any other form of attachment technique, without departing from the scope and spirit of the present invention.

The golf club head ( 600 ) illustrated in FIG. 6 also differs from previous embodiments of the present invention in that it has a crown opening ( 644 ) and a concave ledge ( 642 ) positioned around the perimeter of the crown opening ( 644 ) to accommodate a crown ( 606 ). In this current embodiment of the present invention, the crown (606) may be manufactured from a lightweight composite material to reduce the weight of that portion of the golf club head ( 600 ). Using a lightweight composite material to form the crown ( 606 ) may create more free mass, which may be strategically placed to achieve the aforementioned CG, MOI, and mass distribution values.

FIG. 7 of the attached drawings is another exploded perspective view of the golf club head ( 600 ) from a different angle, showing the front opening ( 621 ) more clearly. As can be seen from this drawing, the front opening ( 621 ) includes the leading edge of the golf club head ( 600 ) and at least partially forms a front portion of the sole of the golf club head ( 600 ). Consequently, due to the shape of the front opening ( 621 ), the striking face ( 620 ) having an L-cup shape forms a leading edge portion of the golf club head ( 600 ) together with the front portion of the sole of the golf club head ( 600 ). However, it should be noted that other types of complementary shapes between the front opening ( 621 ) and the striking face ( 620 ) that are different from the L-cup shape illustrated herein may be used without departing from the scope and content of the present invention, as long as the shape of the striking face ( 620 ) complements the shape of the front opening ( 621 ).

FIG. 8 of the accompanying drawings is a cross-sectional view of a golf club head ( 600 ) taken along a vertical plane passing through the face center ( 622 ) and extending along the Z-axis. This cross-sectional view of the golf club head ( 600 ) illustrates in more detail the various thicknesses and dimensions of the golf club head ( 600 ). First of all, it can be seen that the striking face ( 620 ) can have a variable thickness, with the thickest portion of the striking face having a first thickness ( Tf1 ) located near the geometric face center ( 622 ), and the peripheral portion of the striking face having a reduced thickness ( Tf2 ). Unlike previous embodiments where the striking face had a single thickness, the present invention utilizes a variable face thickness profile to reduce the thickness of the first thickness ( Tf1 ) to about 1.8 mm to about 2.1 mm, more preferably to about 1.9 mm to about 2.1 mm, and most preferably to about 2.0 mm to about 2.1 mm. The second thickness ( Tf2 ) is always smaller than the first thickness ( Tf1 ), and may generally have a thickness of about 1.70 mm to about 1.75 mm, more preferably about 1.70 mm to about 1.73 mm, and most preferably about 1.70 mm to about 1.72 mm.

The cross-sectional view of the golf club head ( 600 ) of FIG. 8 , in addition to illustrating the striking face ( 620 ), shows new important features of the L-cup striking face ( 620 ) along with various dimensions. Among other things, FIG. 8 shows that the striking face ( 620 ) has a sole return ( 623 ) distance ( DR ) that forms the leading edge and front portion of the sole of _the golf club head ( 600 ). The sole return (DR ₎ distance is measured from the most forward portion of the leading edge toward the rear of the L-cup striking face ( 620 ) and may generally be about 9.0 mm to about 11.0 mm, more preferably about 9.5 mm to about 10.5 mm, and most preferably about 10.0 mm in this embodiment of the present invention. In addition to the length of the sole return ( 623 ) distance ( DR ) _, FIG. 8 of the attached drawings also illustrates the thickness of the sole return ( 623 ) thickness ( T _R ). The T _R illustrated in this embodiment of the present invention may generally be from about 0.8 mm to about 1.0 mm, more preferably from about 0.85 mm to about 0.95 mm, and most preferably about 0.9 mm.

Now that the dimensions of the striking face ( 620 ) have been established, it is important to note that the dimensions of this L-cup shaped striking face ( 620 ) are important to the proper performance of the golf club head ( 600 ) of the present invention, particularly the relationship between the substantially vertical planar portion of the L-cup striking face ( 620 ) and the lower return portion of the L-cup striking face (620). Thus, according to the present invention, the golf club head ( 600 ) can have a maximum face thickness to sole thickness ratio of from about 1.70 to about 2.18, more preferably from about 1.78 to about 2.03, and most preferably from about 1.88 to about 1.91, wherein the maximum face thickness to sole return thickness ratio is defined as:

Another important ratio that can be estimated from the dimensions of the golf club head ( 600 ) shown in FIG . 8 is the maximum face thickness to sole return distance ratio, which is defined as:

The maximum face thickness to sole return distance ratio according to the present invention may generally be from about 0.15 to about 0.19, more preferably from about 0.16 to about 0.18, and most preferably about 0.17.

Finally, it should be noted that the sole return ( 623 ) portion of the striking face ( 622 ) includes a unique relationship between sole return ( 623 ) distance and sole return ( 623 ) thickness, creating a sole return distance to thickness ratio defined as:

The sole return distance to thickness ratio according to the present invention may generally be from about 9 to about 13.75, more preferably from about 10 to about 12.35, and most preferably about 11.

In addition to illustrating the dimensions and features of the striking face ( 620 ), FIG . 8 of the accompanying drawings shows some ancillary features of the golf club head ( 600 ). Near the top of the golf club head ( 600 ), it can be seen that the crown ( 606 ) made of a high-strength composite has a thickness ( Tc ) of less than about 0.60 mm, more preferably less than about 0.55 mm, and most preferably less than about 0.54 mm. The ground-to-top radius measurement ( 618 ) of the golf club head ( 600 ) can be from about 33.0 mm to about 36 mm, more preferably from about 34.0 mm to about 35 mm, and most preferably about 34.5 mm. Finally, the peak crown height ( 617 ) of the golf club head ( 600 ) may be from about 36 mm to about 40 mm, more preferably from 37 mm to about 39 mm, and most preferably about 38 mm.

FIGS. 9 , 10 , and 11 of the attached drawings are two exploded perspective views and one cross-sectional view of a golf club head ( 900 ) according to an alternative embodiment of the present invention, wherein the striking face ( 920 ) has a C-cup shaped crown return ( 925 ) in addition to a sole return ( 923 ). A comprehensive examination of FIGS. 9 , 10 , and 11 reveals that the golf club head ( 900 ) has a body portion ( 940 ) having a front opening ( 921 ) without a leading edge and a crown transition portion to accommodate a similarly shaped striking face ( 920 ) having a crown return ( 925 ) and a sole return ( 923 ). Similar to the previously illustrated embodiment, the body portion ( 940 ) may also have a crown opening ( 944 ) having a concave ledge ( 942 ) configured to receive a lightweight crown ( 906 ), typically made of a lightweight composite. The means for attaching the striking face ( 920 ) and crown ( 906 ) to the frontal opening ( 921 ) and crown opening ( 944 ), respectively, are similar to the attachment methods for the striking face ( 620 ) and crown ( 606 ) discussed previously.

The cross-sectional view of the golf club head ( 900 ) illustrated in FIG. 11 is similar to the cross-sectional view of the golf club head ( 600 ) illustrated in FIG. 8 , and shows the interior of the golf club head ( 900 ) more clearly. The cross-sectional view of the golf club head ( 900 ) illustrated therein shows a C-cup shaped striking face ( 920 ) with crown return and sole return as described above, and illustrates how this alternative embodiment can achieve the CG and MOI characteristics and interfaces between the various components described above.

FIG. 12 of the accompanying drawings is a heel side exploded view of a golf club head ( 1200 ) according to another alternative embodiment of the present invention, wherein the striking face ( 1220 ) has an improved variable thickness profile to utilize a sole return ( 1223 ) of the striking face ( 1220 ). Similar to the previous embodiments, the striking face ( 1220 ) with the sole return ( 1223 ) forms an L shape, more commonly referred to as an L-cup face, without departing from the scope and spirit of the present invention. The striking face ( 1220 ) is attached to a body portion ( 1240 ) of the golf club head ( 1200 ), wherein the body portion ( 1240 ) can have a crown opening ( 1244 ) having a concave ledge ( 1242 ) configured to receive a crown ( 1206 ). To better illustrate the improved variable face thickness profile of the striking face ( 1220 ) , FIG. 13 is provided below.

FIG. 13 of the accompanying drawings is an enlarged perspective view of a striking face ( 1220 ) according to this other alternative embodiment of the present invention. This enlarged rear view of the striking face ( 1220 ) will help to explain the variable face thickness profile associated with the present embodiment, which plays a key role in achieving the improved performance of the present striking face ( 1220 ). It should be noted that while the present variable face profile is exemplified and works best with an L-shaped striking face ( 1220 ) having a sole return ( 1223 ), the variable face profile illustrated herein may work with other types of striking faces, such as C-cups, face inserts, or other types of striking face designs, without departing from the scope and spirit of the present invention. The variable thickness profile of the striking face ( 1220 ) may generally be formed by a substantially planar front surface and a non-planar back surface, as illustrated in FIG. 13 of the present invention.

The striking face ( 1220 ) illustrated in FIG. 13 may have a thickened central portion ( 1250 ) that is not typically located near the geometric center of the striking face ( 1220 ) as seen in most conventional designs. In fact, a closer look at the striking face ( 1220 ) illustrated in FIG. 13 reveals that the thickened central portion ( 1250 ) is located closer to the upper crown portion of the golf club head ( 1200 ) ( illustrated in FIG. 12 ) to create a crown-biased location according to this exemplary embodiment of the present invention. Not only is the thickened central portion ( 1250 ) crown-biased in its location, but it also has a unique geometric structure resembling a flat oval, exhibiting a very high aspect ratio compared to conventional variable face thickness designs. As a result, the thickened central portion ( 1250 ) may have a thickened central portion heel end ( 1250-H) and a thickened central portion toe end (1250 -T) that are more pointed than the thickened central portion of a variable face thickness profile associated with a conventional golf club head of the prior art. Due to its unique shape, the thickened central portion is not of a uniform thickness as in a conventional variable face thickness design, but rather the thickened central portion heel end (1250 -H ) and the thickened central portion toe end ( 1250-T ) may be thinner in thickness compared to the central portion of the thickened central portion ( 1250 ).

Above the crown-biased thickened central portion ( 1250 ) is located an upper transition portion ( 1252 ) where the thickness transitions from the thickened central portion ( 1250 ) to the outer perimeter thickness.

As can be seen in Fig. 13 , since the thickened central portion ( 1250 ) is severely crown biased, the transition slope of this upper transition portion ( 1252 ), also called the upper transition slope, can be seen to be very high, especially compared to a conventional variable face thickness profile in which the thickened central portion is positioned closer to the center. Conversely, as a corollary to the above, the lower transition portion ( 1254 ) can exhibit a significantly smaller lower transition slope than a conventional variable face thickness profile in which the thickened central portion ( 1250 ) is positioned closer to the center.

As a result, the mismatch between the slopes of the two transition sections exhibits a higher-than-average value because of the extreme deviations from the conventional variable face thickness design in both the upper transition section ( 1252 ) and the lower transition section ( 1254 ). In other words, the ratio between the upper transition slope and the lower transition slope in the present invention can be said to be considerably higher than that of a conventionally designed striking face.

FIG. 14 of the attached drawings is a direct rear view of the striking face ( 1220 ) and shows some of the dimensional characteristics of the striking face ( 1220 ). Among other things, this direct rear view of the striking face ( 1220 ) shows the extreme elliptical shape of the thickened central portion ( 1250 ) discussed above. The width ( W ) of this extreme elliptical shape of the thickened central portion ( 1250 ) may be typically greater than about 45 mm, more preferably greater than about 50 mm, and most preferably about 52 mm. The height ( H ) of the extreme elliptical shape of the thickened central portion ( 1250 ) may be typically less than about 7 mm, more preferably less than about 6 mm, and most preferably less than about 5 mm. The resulting aspect ratio of the thickened central portion ( 1250 ), defined as width ( W ) divided by height ( H ), can typically be greater than about 5, more preferably greater than about 8, and most preferably greater than about 10.

In addition to illustrating the aspect ratio of the thickened central portion ( 1250 ), FIG. 14 of the attached drawing also shows various heights of the upper transition portion ( 1252 ) and the lower transition portion ( 1254 ) and their measurement locations. The height ( H2 ) of the upper transition portion ( 1252 ) can typically be from about 2.5 mm to about 3.5 mm, more preferably from about 2.75 mm to about 3.25 mm, and most preferably about 3.0 mm. This height ( H2 ) can be used to calculate the upper transition slope discussed above in combination with the thickness at the end range discussed later in the cross-sectional view of the striking face ( 1220 ) shown in FIG . 15 . Similarly, the height ( H4 ) of the lower transition portion ( 1254 ) may typically be about 18 mm to about 19 mm, more preferably about 18.25 mm to about 18.75 mm, and most preferably about 18.50 mm. This height ( H4 ) may also be used to calculate the lower transition slope discussed above in combination with the thickness at the end range of this lower transition portion ( 1254 ), which will be later illustrated in FIG. 15 .

Finally, FIG . 14 of the attached drawings shows a cross-sectional line ( A-A' ) drawn along the geometric face center (shown in FIG. 12 ) of the golf club head (1200 ) to provide a cross-sectional view of the striking face ( 1220 ) of FIG. 15. It should be noted that the cross-sectional line ( A-A' ) shown in FIG. 14 passes through the geometric face center ( 1222) of the club head (1200 ) (shown in FIG. 12 ) and not the striking face ( 1220 ) insert itself.

FIG. 15 of the attached drawings is a cross-sectional view taken along the cross-sectional line ( A-A' ) shown in FIG. 14 of a striking face ( 1220 ) according to another alternative embodiment of the present invention. This cross-sectional view of the striking face ( 1220 ) more clearly shows the variable thickness profile with various thicknesses and heights identified. Most notably, it can be seen that the striking face ( 1220 ) has an L-cup shape and a sole return ( 1223 ) portion. Accordingly, it can be said that the striking face ( 1220 ) can be further separated into an upper transition portion ( 1252 ), a thickened central portion ( 1250 ), a lower transition portion ( 1254 ), and a sole return ( 1223 ) without departing from the scope and spirit of the present invention.

Starting from a portion near the crown ( 106 ) (as shown in FIG. 1 ), the upper thickness ( T1 ) of the upper transition portion ( 1252 ) can be from about 1.65 mm to about 1.85 mm, most preferably from about 1.70 mm to about 1.80 mm, and most preferably about 1.75 mm. Within this upper transition portion ( 1252 ), the thickness of the striking face ( 1220 ) begins to increase very abruptly to a lower thickness ( T2 ) of from about 2.10 mm to about 2.30 mm, more preferably from about 2.15 mm to about 2.25 mm, and most preferably about 2.20 mm. This thickness transition of about 0.45 mm occurs at the aforementioned height ( H2 ) of about 2.5 mm to about 3.5 mm, more preferably about 2.75 mm to about 3.25 mm, and most preferably about 3.0 mm, resulting in a transition slope of greater than about 8 degrees, more preferably greater than about 9 degrees, and most preferably greater than about 10 degrees. In other words, the upper transition portion ( 1252 ) can be said to have an actual slope defined by the slope of the upper transition portion ( 1252 ) of greater than about 0.10, more preferably greater than about 0.125, and most preferably greater than about 0.15.

Based on the angles and slopes defined above, the ratio of the upper transition slope to the lower transition slope is preferably greater than about 1.14, more preferably greater than about 1.5, and most preferably greater than about 2.0. This ratio of the lower transition slope to the upper transition slope is very important for the balance of performance and durability of the striking face ( 1220 ) according to the present invention.

Immediately beneath the above upper transition portion, there is a thickened central portion ( 1250 ) which can have a generally constant thickness in the vertical direction, and as a result, the thicknesses ( T2 and T3 ) can be the same, from about 2.10 mm to about 2.30 mm, more preferably from about 2.15 mm to about 2.25 mm, and most preferably about 2.20 mm. It should be noted here that, although the thickness of the thickened central portion ( 1250 ) is constant in the vertical direction as illustrated in FIG. 15 , the thickness thereof is tapered in the horizontal direction, such that the thickened central portion heel end ( 1250-H ) and the thickened central portion toe end ( 1250-T ) are reduced to the aforementioned thickness ( T1 ), thereby creating a variable thickness in that region from a different perspective than that presented in FIG. 15 .

Immediately beneath the thickened central portion ( 1250 ) is a lower transition portion where the thickness decreases from ( T3 ) to ( T4 ). While the thickness ( T3 ) has already been discussed as being the same as the thickness ( T2 ), the thickness ( T4 ) according to the present invention may typically be from about 1.45 mm to about 1.65 mm, more preferably from about 1.50 mm to about 1.60 mm, and most preferably about 1.55 mm. This lower transition portion thickness decrease of about 0.65 mm occurs more gradually over a height ( H4 ) of about 18 mm to about 19 mm, more preferably from about 18.25 mm to about 18.75 mm, and most preferably about 18.50 mm, as previously mentioned. This essentially identical thickness reduction in the lower transition portion ( 1254 ) occurs over a significantly longer range than in the lower transition portion ( 1252 ), thus creating a lower transition slope of less than about 7 degrees, more preferably less than about 6 degrees, and most preferably less than about 5 degrees. In other words, the lower transition portion ( 1254 ) can be said to have an actual slope defined by the slope of the upper transition portion ( 1252 ) of less than about 0.05, more preferably less than about 0.04, and most preferably less than about 0.035.

FIG. 15 of the attached drawing not only shows various thicknesses of the front planar portion of the striking face ( 1220 ), but also shows three thicknesses of the sole return ( 1223 ) which exhibit unique thickness profiles. The initial front thickness ( T5 ) of the sole return ( 1223 ) is approximately 0.85 mm exactly 2.9 mm rearward from the forward-most point ( 1225 ) of the striking face. This sole return ( 1223 ) decreases to an intermediate thickness ( T6 ) of approximately 0.72 mm exactly 6.2 mm rearward from the forward-most point ( 1225 ). Finally, the sole return ( 1223 ) reverses the thickness trend by increasing in thickness to a trailing thickness ( T7 ) of approximately 0.90 mm exactly 9.2 mm rearward from the forward-most point. This unique thickness profile, which transitions from thin to thick and back to thin again, is a very important factor in the performance of the striking face ( 1220 ) of the L-cup face, enabling faster ball speeds on low hits on the striking face ( 1220 ). In other words, the sole return ( 1233 ) can have a larger initial frontal thickness ( T5 ) than the middle thickness ( T6 ), and the terminal thickness ( T7 ) can generally be larger than the initial frontal thickness ( T5 ). Since the initial frontal thickness ( T5 ) is already larger than the middle thickness ( T6 ), the terminal thickness ( T7 ) can also be larger than the middle thickness ( T6 ).

FIG. 16 of the attached drawings is a rear view of a striking face ( 1620 ) according to an alternative embodiment of the present invention. More specifically, in this alternative embodiment of the present invention, the golf club head may be an iron type golf club head instead of a metalwood type golf club head, and both embodiments include a sole return ( 1623 ). It should be noted that in this current embodiment of the present invention, the striking face ( 1620 ) may have a uniquely different thickness profile that is worth emphasizing.

Here, the thickness profile is a three-dimensional distribution that can be quantified by three different face regions. First, the striking face ( 1620 ) can be separated into a central region ( 1660 ), a heel region ( 1662 ), and a toe region ( 1666 ). The central region ( 1660 ) can generally have a uniform thickness that includes the geometric face center ( 1622 ). The central region ( 1660 ) can be wider at the top near the top line of the striking face ( 1620 ) and can taper significantly toward the bottom sole portion of the striking face ( 1620 ). In other words, the central region ( 1660 ) can be said to be "V" shaped without departing from the scope and content of the present invention. The thickness of the central region ( 1660 ) may be generally from about 1.60 mm to about 1.90 mm, more preferably from about 1.70 mm to about 1.80 mm, and most preferably about 1.75 mm, without departing from the scope and content of the present invention.

The "V" shaped central region ( 1660 ) of the striking face ( 1620 ) having a wider top portion and a narrower bottom portion can be quantified by the bottom angle (θ) of the "V" shape, where a larger bottom angle (θ) indicates a wider top portion and a smaller bottom angle (θ) indicates a narrower top portion. More specifically, the bottom angle (θ) according to this embodiment of the present invention is typically greater than about 20 degrees, more preferably greater than about 25 degrees, and most preferably greater than about 30 degrees. In the exemplary embodiment illustrated in FIG. 16 , the heel complementary angle (α) on the heel side and the toe complementary angle (β) on the toe side are each equal to about 75 degrees since the sum of the angles (α, β, and θ) is 180 degrees. However, in alternative embodiments of the present invention, the heel complementary angle (α) and the toe complementary angle (β) can be different from each other without departing from the scope and spirit of the present invention.

Paired with the center area ( 1660 ) are the toe area ( 1662 ) on the heel side of the striking face ( 1620 ) and the toe area ( 1666 ) on the toe side of the striking face ( 1620 ), which complete the striking face ( 1620 ). Because the center area ( 1660 ) is wider at the top and narrows toward the bottom, the area widths of the heel area ( 1662 ) and the toe area ( 1666 ) are generally inversely related. More specifically, both the heel area ( 1662 ) and the toe area ( 1666 ) are wider at the bottom and gradually narrow as they approach the top line of the striking face ( 1620 ).

If the shape and distribution of the heel region ( 1662 ) and toe region ( 1666 ) have been established above, a discussion can proceed on the thickness of the heel region ( 1662 ) and toe region ( 1666 ), both of which have variable thicknesses. The variable face thickness profiles in the heel area ( 1662 ) and toe area ( 1666 ) are determined by two design criteria: the first is that the thickness of the heel area ( 1662 ) and the thickness of the toe area ( 1666 ) are thickest at the topline and gradually thinner toward the bottom sole area of the striking face ( 1620 ); and the second is that the thickness of the heel area ( 1662 ) and the thickness of the toe area ( 1666 ) are thickest near the center area ( 1660 ) and gradually thinner toward the ends of the heel area ( 1662 ) and toe area ( 1666 ).

Consequently, based on the above two design criteria, the thickest portion ( 1661 ) of the heel region (1662) can generally be located at the upper toe portion of the heel region ( 1662 ), and the maximum thickness similar to the central region ( 1660 ) is about 1.60 mm to about 1.90 mm, more preferably about 1.70 mm to about 1.80 mm, and most preferably about 1.75 mm. This heel region ( 1662 ) gradually transitions from the thickest portion (1661) to the thinnest portion ( 1663 ) located at the heel bottom of the heel region ( 1662 ), and the thickness of the thinnest portion ( 1663 ) is about 1.49 mm to about 1.79 mm, more preferably about 1.59 mm to about 1.69 mm, and most preferably about 1.64 mm.

Similarly, applying the above two design criteria to the toe region ( 1666 ), the location of the thickest region (1665), which has a maximum thickness similar to that of the central region ( 1660 ), is generally located above the heel of the toe region ( 1666 ). The toe region ( 1666 ) gradually transitions from the thickest portion ( 1665 ) to the thinnest portion ( 1667 ), which is located below the toe of the heel region ( 1666 ), and has a thickness of about 1.48 mm to about 1.78 mm, more preferably about 1.58 mm to about 1.68 mm, most preferably about 1.63 mm.

FIG. 17 of the attached drawings is a cross-sectional view of an iron _- type golf club head ( 1700 ) according to an alternative embodiment of the present invention, wherein the sole return distance ( DR ) is shown in more detail in relation to the total sole width distance ( DS ) _. More specifically, _the sole return distance ( DR ) can generally be from about 9.00 mm to about 12.00 mm, more preferably from about 9.50 mm to about 11.50 mm, and most preferably about 10.50 mm. On the other hand, _the sole width distance ( DS ) can generally be from about 20.0 mm to about 26.0 mm, more preferably from about 21.0 mm to about 25.0 mm, and most preferably about 23.0 mm. Based on the values mentioned above, the ratio of D _R to D _S can generally be greater than about 30% and less than about 60%, more preferably greater than about 40% and less than about 60%, and most preferably greater than about 45% and less than about 60% without departing from the scope and content of the present invention.

In addition to showing the sole return distance of the sole return ( 1723 ), FIG. 17 of the attached drawing is a cross-section taken from the geometric face center ( 1622 ) shown in FIG. 16 , which also shows the thickness in the central region ( 1660 ) of the striking face ( 1723 ). As described above, the thickness of the central region ( 1660 ) of the striking face ( 1620 ) is constant, so that the resulting maximum face thickness ( T _f1 ) is generally about 1.60 mm to about 1.90 mm, more preferably about 1.70 mm to about 1.80 mm, and most preferably about 1.75 mm.

FIG. 18 of the attached drawings is an enlarged view of a golf club head ( 1700 ) according to an embodiment of the present invention illustrated in FIG. 17 , showing in more detail the thickness of the striking face ( 1720 ) and its sole return ( 1723 ). In this embodiment of the present invention, the sole return ( 1723 ) may exhibit a thickness transition pattern similar to that illustrated in the previous embodiment, starting with a thin thickness ( T5 ) in the initial front portion, gradually thinning in the middle portion with an intermediate thickness ( T6 ), and finally ending in the end portion with the thickest of the three thicknesses, the end thickness ( T7 ).

More specifically, in this iron embodiment of the present invention, the initial front thickness ( T5 ) of the sole return ( 1723 ) may generally be from about 1.3 mm to about 1.8 mm, more preferably from about 1.3 mm to about 1.7 mm, and most preferably from about 1.3 mm to about 1.6 mm. The middle thickness ( T6 ) of the sole return ( 1723 ) may generally have a thickness of from about 1.2 mm to about 1.7 mm, more preferably from about 1.2 mm to about 1.6 mm, and most preferably from about 1.2 mm to about 1.5 mm. Finally, the trailing thickness ( T7 ) of the sole return ( 1723 ) may generally have a thickness greater than about 1.5 mm, more preferably greater than about 1.55 mm, and most preferably greater than about 1.60 mm.

Although a thickness transition of the sole return ( 1723 ) is generally desirable to achieve maximum performance of the striking face ( 1720 ), the sole return ( 1723 ) may have a constant thickness maintained throughout the sole return ( 1723 ) in alternative embodiments of the present invention without departing from the scope and spirit of the present invention.

Based on the thickness values described for these alternative iron embodiments, it can be seen that different maximum face thickness to sole return thickness ratios are generated here, ranging from about 1.05 to about 1.15, more preferably from about 1.07 to about 1.13, and most preferably about 1.1, with the maximum face thickness to sole return thickness ratios being defined slightly differently below due to the variable thickness of the sole return ( 1723 ).

FIG. 19 of the accompanying drawings is a rear view of a striking face ( 1920 ) of an iron-type golf club head according to an alternative embodiment of the present invention. In this embodiment of the present invention, the striking face ( 1920 ) of the golf club head may still be separated into a central region ( 1960 ), a heel region ( 1962 ), and a toe region ( 1966 ). The central region ( 1960 ) in this embodiment of the present invention may also be a "V" shape with an upper portion wider than a lower portion, but in this embodiment, the "V" shape may only partially extend downward from the upper portion of the striking face ( 1920 ) to form an upper central region ( 1960a ) that is different from a lower central region ( 1960b ). The upper central region ( 1960a ) may have a thickness generally similar to the previous embodiment, typically from about 1.60 mm to about 1.90 mm, more preferably from about 1.70 mm to about 1.80 mm, and most preferably from about 1.75 mm.

The new lower center region ( 1960b ) is designed differently to taper downward from the constant thickness of the upper center region ( 1960a ) to a thinner lower center region of the striking face ( 1920 ). This thinner lower center region improves the performance of the golf club head by increasing ball speed at low impact locations. The addition of this lower center region ( 1960b ) creates an additional transition region that tapers toward the heel region ( 1962 ) and toe region ( 1966 ) without departing from the scope and spirit of the present invention.

The heel region ( 1961 ) of the striking face ( 1920 ) of the alternative embodiment of the present invention illustrated in FIG. 19 may have, similar to the previous embodiment, a thickest portion ( 1961 ) located at the upper toe portion of the heel region ( 1962 ), and a maximum thickness similar to the central region ( 1960 ) of about 1.60 mm to about 1.90 mm, more preferably about 1.70 mm to about 1.80 mm, and most preferably about 1.75 mm. This heel region ( 1962 ) gradually transitions from the thickest portion ( 1661 ) to the thinnest portion ( 1963 ) located at the lower heel portion of the heel region ( 1962 ), and the thickness of the thinnest portion ( 1963 ) is about 1.49 mm to about 1.79 mm, more preferably about 1.59 mm to about 1.69 mm, and most preferably about 1.64 mm.

Similarly, applying the above two design criteria to the toe region ( 1966 ), the location of the thickest region (1965), which has a maximum thickness similar to that of the center region ( 1960 ), is generally located above the heel of the toe region ( 1966 ). The toe region ( 1966 ) gradually transitions from the thickest portion ( 1965 ) to the thinnest portion ( 1967 ) , which is located below the toe of the heel region (1966 ) , and has a thickness of about 1.48 mm to about 1.78 mm, more preferably about 1.58 mm to about 1.68 mm, most preferably about 1.63 mm.

Additionally, the striking face ( 1920 ) illustrated in this embodiment of the present invention may have a similar sole return with a similar thickness and depth as previously illustrated.

FIG. 20 of the accompanying drawings is a rear view of another striking face ( 2020 ) of a golf club head according to another alternative embodiment of the present invention having a sole return ( 2023 ). In this embodiment of the present invention, the shape of the variable thickness profile has an elliptical central region, details of which can be found in U.S. patent application Ser. No. 18/428,288, filed Jan. 31, 2024, the disclosure of which is incorporated by reference in its entirety.

It should be noted that despite the completely different face thickness design, the sole return ( 2023 ) design of the striking face ( 2020 ) may have similar thicknesses and dimensions as previously discussed to achieve performance advantages without departing from the scope and teachings of the present invention.

Although the numerical ranges and parameters defining the broad scope of the present invention are approximations, the numerical values presented in specific examples are reported as precisely as possible. However, any numerical value inherently contains certain errors inherent in the standard deviation found in each test measurement. Furthermore, when multiple numerical ranges are presented herein, it is contemplated that any combination of these values, including the recited values, may be used.

Of course, it should be understood that the foregoing is merely an exemplary embodiment of the present invention, and that modifications may be made without departing from the spirit and scope of the present invention as set forth in the claims below.

Claims (21)

As a golf club head,
A golf club head comprising a striking face having a center of the face, a crown, a sole opposite the crown, a heel, a toe opposite the heel, and a hosel adjacent to the heel and configured to couple the golf club head to a shaft.
The above striking face is
Further comprising a variable face thickness profile having a substantially planar front surface and a non-planar back surface,
The X-axis is defined as a horizontal axis tangent to the center of the face of the striking face and having a positive direction toward the heel of the golf club head, the Y-axis is a vertical axis perpendicular to the X-axis and having a positive direction toward the crown of the golf club head, the Z-axis is perpendicular to both the X-axis and the Y-axis and having a positive direction toward the front of the golf club head, and the origins of the X-axis, the Y-axis and the Z-axis are located at the center of gravity (CG) of the golf club head.
The above variable face thickness profile of the above striking face is
A central area of constant thickness,
The heel area, which decreases in thickness from the upper toe area to the lower heel area, and
A golf club head characterized by further including a toe region whose thickness decreases from the upper heel region to the lower toe region. A golf club head, characterized in that the central region in the first paragraph forms a V shape. A golf club head, characterized in that in the second paragraph, the V shape of the central region forms a lower angle (θ) greater than about 20 degrees. A golf club head, characterized in that in the third paragraph, the lower angle (θ) is greater than about 25 degrees. A golf club head, characterized in that in claim 4, the lower angle (θ) is greater than about 30 degrees. A golf club head, characterized in that in the second paragraph, the heel angle (α) and the toe angle (β) of the striking face are the same. A golf club head, characterized in that in the second paragraph, the heel angle (α) and the toe angle (β) of the striking face are different. A golf club head, characterized in that the central region of the striking face in the first paragraph has a uniform thickness of about 1.60 mm to about 1.90 mm. A golf club head, characterized in that in claim 8, the heel region of the striking face has a maximum thickness of about 1.60 mm to about 1.90 mm and a minimum thickness of about 1.49 mm to about 1.79 mm. A golf club head, characterized in that in claim 8, the toe area of the striking face has a maximum thickness of about 1.60 mm to about 1.90 mm and a minimum thickness of about 1.48 mm to about 1.78 mm. As a golf club head,
A golf club head comprising a striking face having a center of the face, a crown, a sole opposite the crown, a heel, a toe opposite the heel, and a hosel adjacent to the heel and configured to couple the golf club head to a shaft.
The above striking face is
Further comprising a variable face thickness profile having a substantially planar front surface and a non-planar back surface,
The X-axis is defined as a horizontal axis tangent to the center of the face of the striking face and having a positive direction toward the heel of the golf club head, the Y-axis is a vertical axis perpendicular to the X-axis and having a positive direction toward the crown of the golf club head, the Z-axis is perpendicular to both the X-axis and the Y-axis and having a positive direction toward the front of the golf club head, and the origins of the X-axis, the Y-axis and the Z-axis are located at the center of gravity (CG) of the golf club head.
The above variable face thickness profile of the above striking face is
A central area that is wider near the top line of the striking face and narrows towards the bottom sole of the striking face;
Heel area, and
A golf club head characterized by further including a toe area. A golf club head, characterized in that in claim 11, the central region forms a lower angle greater than about 25 degrees. A golf club head, characterized in that in claim 12, the lower angle of the central region is greater than about 30 degrees. A golf club head, characterized in that the lower angle of the central region in the 13th paragraph is greater than about 35 degrees. In the 12th paragraph, the striking face further includes a sole extension near the sole,
The above sole extension is
Initial front with initial front thickness,
A middle part with medium thickness, and
A golf club head characterized by further including a terminal portion having a terminal thickness. In the 15th paragraph, the initial front thickness is greater than the intermediate thickness,
A golf club head, characterized in that the terminal thickness is greater than the intermediate thickness. As a golf club head,
A golf club head comprising a striking face having a center of the face, a crown, a sole opposite the crown, a heel, a toe opposite the heel, and a hosel adjacent to the heel and configured to couple the golf club head to a shaft.
The above striking face further includes a sole extension near the sole,
The above sole extension is
Initial front with initial front thickness,
A middle part with medium thickness, and
Including further end portions having end thickness,
The above striking face is
Further comprising a variable face thickness profile having a substantially planar front surface and a non-planar back surface,
The X-axis is defined as a horizontal axis tangent to the center of the face of the striking face and having a positive direction toward the heel of the golf club head, the Y-axis is a vertical axis perpendicular to the X-axis and having a positive direction toward the crown of the golf club head, the Z-axis is perpendicular to both the X-axis and the Y-axis and having a positive direction toward the front of the golf club head, and the origins of the X-axis, the Y-axis and the Z-axis are located at the center of gravity (CG) of the golf club head.
The above variable face thickness profile of the above striking face is
A central area that is wider near the top line of the striking face and narrows towards the bottom sole of the striking face;
Heel area, and
A golf club head characterized by further including a toe area. In the 17th paragraph, the initial front thickness is greater than the intermediate thickness,
A golf club head, characterized in that the terminal thickness is greater than the intermediate thickness. A golf club head, characterized in that in claim 18, _the ratio of sole return distance ( DR ₎ to sole width distance ( DS ) is greater than about 30% and less than about 60%. A golf club head, characterized in that in claim 19, the ratio of the sole return distance ( DR ₎ to _the sole width distance ( DS ) is greater than about 40% and less than about 60%. A golf club head, characterized in that in claim 20, the ratio of the sole return distance ( DR ₎ to _the sole width distance ( DS ) is greater than about 45% and less than about 60%.