Patent Grant
8562458
The present invention relates to an improved striking face of a golf club head. More specifically, the present invention relates to a striking face having a thickened central region surrounded by an internal and an external transition region; wherein the thickened central region has a central perimeter that takes on a shape that substantially resembles the shape of a face perimeter of the striking face of the golf club head.
The game of golf has always been closely linked to the equipment used to play the game itself. Although the actual game of golf has not changed much since its inception in the early days of Scotland, the equipment used to play the game of golf has made significant transformations. Although it is debatable which of the numerous golf equipments have changed the most since the early days of golf, it is hard to argue that the current state of a metalwood type golf clubs are a dramatic deviation from the persimmon woods originally used during the early stages of the game of golf.
Metalwood clubs, based on their inherent design, improves upon the performance of a persimmon wood type golf club head by creating a hollowed metallic shell; which in turn, may drastically increase the coefficient of restitution of the golf club head by allowing the striking face to deflect during impact. In addition to increasing the coefficient of restitution, metalwood type golf club heads have made the game of golf easier for the average golfer by increasing the moment of inertia of the golf club head, which results from the increase in size while maintaining the stability of the golf club through impact.
Despite all the performance gains above, golf club designers have pushed the performance boundary even further by varying the thicknesses of the back of the striking face of the golf club head. Varying the thickness of the back portion of the striking face of the golf club head improves the performance of the golf club head by adjusting the flexural stiffness of the striking face of the golf club head to strategically improve the size and shape of the sweet spot on the striking face; wherein the sweet spot is defined as the portion of the striking face capable of achieving a high coefficient of restitution.
U.S. Pat. No. 6,319,150 illustrates one of the earlier attempts at varying the thickness of the face wall to maximize face strength with minimum face mass, U.S. Pat. No. 6,319,150 provides a golf club that increases the maximum size of the hitting face of the golf club that is usable by having a varying thickness to allow for additional weight to be saved and placed at strategically placed at alternative locations to improve the moment of inertia of the golf club head.
Although these early attempts at adjusting the thickness of the striking face of the golf club head are admirable in providing a foundation for the future development of this concept, most of them do not fully realize the performance benefits that can be achieved by optimizing the size, shape, and geometry of the variable thickness profile at the rear of the striking face based on the size, shape, and geometry of the striking face, U.S. Pat. No. 6,652,391 shows one attempt at varying the size, shape, and geometry of the striking face of the golf club head in an attempt to improve the performance, but it fails to correlate it to the size, shape, and geometry of the striking face itself. More specifically, U.S. Pat. No. 6,652,391 discloses a front wall that varies in thickness and has a bulging area of increased thickness on its inner surface. The bulging area of increased thickness includes a generally ring shaped mass that projects rearwardly from the front wall. A generally cone shaped mass, that also projects rearwardly from the front wall, may be located inside the ring shaped mass.
U.S. Pat. No. 6,997,820 provides another example of an alternative attempt to adjust the size, shape, and geometry of the thickness geometry behind a striking plate to further improve upon the fundamental concept of a golf club having a variable thickness face. In doing so, U.S. Pat. No. 6,997,820 discloses a face plate having a vertical zone of increased thickness and a central region having a reduced thickness. An upward extension of the vertical zone comprises divergent segments separated by an upper region of reduced thickness.
U.S. Pat. No. 7,137,907 provides a further example of another completely different geometry used to adjust the performance of a striking plate of a golf club head. More specifically, U.S. Pat. No. 7,137,907 discloses a face insert having an interior surface with a first thickness section and a second thickness region. The first thickness section preferably has a thickness that is at least 0.025 inch greater than the thickness of the second thickness region.
U.S. Pat. No. 6,623,377 provides yet another example of an attempt to adjust the performance of the golf club head by changing the thickness of the striking face. More specifically, U.S. Pat. No. 6,623,377 discloses a golf club head having a striking plate with regions of varying thickness having a central region of a first thickness that is thicker than the thickness range of any other region. The thickness of the regions decreases outward from the center.
Despite numerous attempts at adjusting the size, shape, and geometry of the rear surface of the striking face of a golf club head, none of the above mentioned patents have investigated the relationship between the size, shape, and geometry of the striking face as it relates to the geometry of the overall geometry of the striking face itself. A golf club with an optimized striking face in terms of its size, shape, and geometry may greatly improve the coefficient of restitution of the golf club head as well as increase the sweet spot of the golf club head.
Hence, as it can be seen from above, despite all the advancement in golf club technology, the current art has not carefully examined the relationship between the size, shape, and geometry of the striking face as it relates to the size, shape, and geometry of the variable face thickness profile behind the striking face. The current art, despite its numerous attempts at varying the thickness of the striking face, falls short by using random geometries that do not completely optimize the performance capabilities of a golf club head as it relates to the striking face itself. Ultimately, it can be seen from above that there is a need in the art for a golf club head that has a variable thickness geometry that optimizes the size, shape, and geometry of the various thickness levels as it relates to the striking face of the golf club head itself.
One aspect of the present invention is a golf club head having a crown, a sole, and a skirt. The golf club head further comprises a striking face portion located at a frontal portion of the golf club head adapted to strike a golf ball and a body portion connected to the aft portion of the striking face portion. The striking face portion has a face perimeter and further comprises a thickened central region having a central perimeter, and a transition region having a transition perimeter. The central perimeter of the golf club head has a geometric shape that is substantially similar to the geometric shape of the face perimeter, and the transition region is thicker at the crown portion of the striking face than it is at the sole portion; creating a cantenary curve near the upper portion of the striking face.
Another aspect of the present invention is a golf club head having a crown, a sole, and a skirt. The golf club head further comprises a striking face portion located at a frontal portion of the golf club head adapted to strike a golf ball and a body portion connected to the aft portion of the striking face portion. The striking face portion has a face perimeter and further comprises a thickened central region having a central perimeter, and a transition region having a transition perimeter. The central perimeter of the golf club head has a geometric shape that is substantially similar to the geometric shape of the face perimeter; and a ratio of the total length of the central perimeter divided by a total length of the face perimeter is greater than about 0.23 and less than about 0.32.
A further aspect of the present invention is a golf club head having a crown, a sole, and a skirt. The golf club head further comprises a striking face portion located at a frontal portion of the golf club head adapted to strike a golf ball and a body portion connected to the aft portion of the striking face portion. The striking face portion has a face perimeter and further comprises a thickened central region having a central perimeter, and a transition region having a transition perimeter. The ratio of the total length of the central perimeter divided by a total length of the face perimeter is greater than about 0.2.3 and less than about 0.32.
These and other features, aspects and advantages of the present invention will become better understood with reference to the following drawings, description and claims.
The foregoing and other features and advantages of the invention will be apparent from the following description of the invention as illustrated in the accompanying drawings. The accompanying drawings, which are incorporated herein and form a part of the specification, further serve to explain the principles of the invention and to enable a person skilled in the pertinent art, to make and use the invention.
The following detailed description describes the best currently contemplated modes of carrying out the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims.
Various inventive features are described below and each can be used independently of one another or in combination with other features. However, any single inventive feature may not address any or all of the problems discussed above or may only address one of the problems discussed above. Further, one or more of the problems discussed above may not be fully addressed by any of the features described below.
In order to more closely examine the internal geometry of the striking face portion 102, a cross-sectional view of the golf club head 100 must be first defined.
Similar to the internal transition region 322, the external transition region 324 is also not symmetrical in the vertical direction. The upper external transition region 324a may generally be thicker than the lower external transition region 324b. More specifically, the thickness d4 of the upper external transition region 324a near the crown portion of the striking face 302 may generally transition from about 2.90 mm to about 2.93 mm, more preferably from about 2.80 mm to about 2.83 mm, and most preferably from about 2.70 mm to about 2.73 mm. The thickness d5 of the lower internal transition region 324b near the sole portion of the striking face 302 may gradually transition from about 2.80 mm to about 2.78 mm, more preferably from about 2.70 min to about 2.68 mm, and most preferably from about 2.60 mm to about 2.58 mm. Based on the various thicknesses d1, d2, d3, d4, and d5 mentioned above, it can be seen that the striking face 302 shown in this exemplary embodiment of the present invention may have a thicker upper portion, a thinner lower portion, combined with a thickened central region 320 to help create a geometry that optimizes the performance of the golf club head 300. Alternatively speaking, it can be said that the upper internal transition region 322a and the upper external transition region 324a combine with one another to form a catenary curve near the upper portion of the striking face 302 while the lower internal transition region 322b and the lower external transition region 324b form a curve that is constantly decreasing in thickness.
It is worth noting that in
The boundaries of the face perimeter 525, as shown in the current exemplary embodiment of the present invention in
Now that the boundary of the face perimeter 525 has been established, the relationship between the face perimeter 525 and the central perimeter 521 may now be defined. As previously stated, the size, shape, and geometry of the thickened central region 520 may be substantially similar to the size, shape, and geometry of the striking face 502, and their relationship relative to one another helps quantify the performance gains of the golf club head. In addition to the similarity in size, shape, and geometry between the thickened central region 520 and the striking face 502, the inner transition region 522 may also have a size, shape, and geometry that is substantially similar to the striking face 502. In the current exemplary embodiment of the present invention, the length of the central perimeter 521 may generally be greater than about 65 mm and less than about 80 mm, more preferably greater than about 70 mm and less than about 75 mm, most preferably about 73 mm. The length of the face perimeter 525, on the other hand, may generally be greater than about 250 mm and less than about 280 mm, more preferably greater than about 260 mm and less than about 270 mm, and most preferably about 265 mm.
An evaluation of the different perimeter lengths mentioned above provides a very important relationship between the central perimeter 521 and the face perimeter 525. More specifically, based on the above, it can be concluded that the ratio of the length of the central perimeter 521 divided by the length of the face perimeter 525 may generally be greater than about 0.23 and less than about 0.32, more preferably greater than about 0.26 and less than about 0.28, and most preferably about 0.27. This ratio of the central perimeter 521 divided by the face perimeter 525 is important to the performance of the golf club head because it controls the size of the thickened central region 520, which controls the size of the sweet spot.
In addition to the various geometric relationships discussed above, the size of the thickened central region 520 is also important to the performance of the striking face 502 of the golf club head. More specifically, as it can be seen in
Finally, it is worth recognizing here that the rear view of the striking face 502 shown in
For comparative purposes,
Other than in the operating example, or unless otherwise expressly specified, all of the numerical ranges, amounts, values and percentages such as those for amounts of materials, moment of inertias, center of gravity locations, loft, draft angles, various performance ratios, and others in the aforementioned portions of the specification may be read as if prefaced by the word “about” even though the term “about” may not expressly appear in the value, amount, or range. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the above 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.
Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements. Furthermore, when numerical ranges of varying scope are set forth herein, it is contemplated that any combination of these values inclusive of the recited values may be used.
It should be understood, of course, that the foregoing relates to exemplary embodiments of the present invention and that modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims.
The present application is a Continuation of co-pending U.S. patent application Ser. No. 12/972,807, filed Dec. 20, 2012, the disclosure of which is incorporated by reference in its entirety.
| Number | Name | Date | Kind |
|---|---|---|---|
| 5366223 | Werner et al. | Nov 1994 | A |
| 5971868 | Kosmatka | Oct 1999 | A |
| 6319150 | Werner et al. | Nov 2001 | B1 |
| 6368234 | Galloway | Apr 2002 | B1 |
| 6402637 | Sasamoto et al. | Jun 2002 | B1 |
| 6428426 | Helmstetter et al. | Aug 2002 | B1 |
| 6428427 | Kosmatka | Aug 2002 | B1 |
| 6508722 | McCabe et al. | Jan 2003 | B1 |
| 6558272 | Helmstetter et al. | May 2003 | B2 |
| 6623377 | Evans et al. | Sep 2003 | B2 |
| 6652391 | Kubica et al. | Nov 2003 | B1 |
| 6776726 | Sano | Aug 2004 | B2 |
| 6800040 | Galloway et al. | Oct 2004 | B2 |
| 6899638 | Iwata et al. | May 2005 | B2 |
| 6997820 | Willett et al. | Feb 2006 | B2 |
| 7101289 | Gibbs et al. | Sep 2006 | B2 |
| 7137907 | Gibbs et al. | Nov 2006 | B2 |
| 7220190 | Hirano | May 2007 | B2 |
| 7338388 | Schweigert et al. | Mar 2008 | B2 |
| 7347794 | Schweigert | Mar 2008 | B2 |
| 7584531 | Schweigert et al. | Sep 2009 | B2 |
| 7749096 | Gibbs et al. | Jul 2010 | B2 |
| 8272975 | Morin et al. | Sep 2012 | B2 |
| 8303432 | Curtis et al. | Nov 2012 | B2 |
| 20020160856 | Evans et al. | Oct 2002 | A1 |
| 20040116206 | Evans et al. | Jun 2004 | A1 |
| 20050137029 | Evans et al. | Jun 2005 | A1 |
| Number | Date | Country |
|---|---|---|
| 2005143601 | Jun 2005 | JP |
| 2010051707 | Mar 2010 | JP |
| 2011125723 | Jun 2011 | JP |
| Number | Date | Country | |
|---|---|---|---|
| 20130012333 A1 | Jan 2013 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 12972807 | Dec 2010 | US |
| Child | 13619882 | US |
