WO2016138133A1

WO2016138133A1 - Golf club with improved weighting

Info

Publication number: WO2016138133A1
Application number: PCT/US2016/019363
Authority: WO
Inventors: Dustin A. Barksdale; Donald S. Bone; Stephanie Bezilla
Original assignee: Acushnet Company
Priority date: 2015-02-26
Filing date: 2016-02-24
Publication date: 2016-09-01
Also published as: US20170028280A1; CN105920816A; JP2016159151A; US20160250528A1

Abstract

A plurality of two or more golf clubs with improved weighting characteristics s is disclosed. More specifically, the present invention discloses s specific relationship between the mass M_club of the golf club and the length L_club to help improve the performance of the golf club.

Description

Attorney Docket No. 9808-380-POA

GOLF CLUB WITH IMPROVED WEIGHTING

FIELD OF THE INVENTION

[0001] The present invention relates generally to a set of golf clubs with improved weighting characteristics. More specifically, the present invention relates a plurality of two or more golf clubs that creates increases in mass as the clubs get shorter in length. This inverse relationship between the length of the club and the mass of the club helps improve the performance of the set of golf club heads by creating a lighter softer shaft for longer golf clubs while creating a heavier stiffer shaft for shorter irons. The present invention achieves this by focusing its attention on adjusting the mass of the shaft portion of the golf club to create the desired results. However, it should be noted that because the shaft is ultimately only a component of a golf club, the focus of the present invention is directed at a golf club with improved weighting.

BACKGROUND OF THE INVENTION

[0002] A golf club contains several key components, all of which can affect the overall performance of a golf club head. Although most golf club improvements focus on the club head portion of the golf club, significant improvements can be made to other portions of the golf club as well.

[0003] U.S. Patent No. 7,175,538 to Miller illustrates one of these examples of improvements to other portions of the golf club head by focusing its attention on the grip of the golf club. U.S. Patent No. 7,175,538 provides a golf club grip having the diameter of the grip progressively reduced from one the butt end to the opposing end.

[0004] U.S. Patent No. 5,71 1,721 to Johnson et al. illustrates another example of an improvement to a golf club head by focusing on the ferrule of the golf club. U.S. Patent No. 5,711,721 provides a ferrule for a golf club that has at least one raised element with a top surface and a second member molded about the first member to surround the raised element to provide logo display or indicia.

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[0005] U.S. Patent No. 5,049,422 to Honma provides an example of an improvement to the shaft portion of the golf club head. In U.S. Patent No. 5,049,422 the inventor taught a shaft for golf club which can exhibit a vibration characteristic of a steel shaft without imparting the characteristics of a carbon shaft. The inventor does this by creating metal fibers incorporated in an outer layer portion of a carbon shaft with a specific direction of metal fiber orientation.

[0006] The present invention focuses on improving the performance of the golf club itself by adjusting, among many other factors, the shaft portion of the golf club. It utilizes a very specific relationship between the length of the golf club together with the overall mass of the golf club to create a set of golf club with improved performance throughout the entire set of golf clubs.

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BRIEF SUMMARY OF THE INVENTION

[0007] In one aspect of the present invention is a golf club comprising of a club head located at a distal end of said golf club, a grip located at a proximal end of said golf club, and a shaft, juxtaposed between the club head and the grip, connecting the club head to the grip, wherein the mass of the golf club decreases with an increase in a length

of said golf club in accordance with the relationship,

[0008] In another aspect of the present invention is a plurality of golf clubs comprising of a first golf club having a length greater than about 38 inches having a first mass, a second golf club having a length of between about 36 to 38 inches having a second mass, and a third golf club having a length of less than about 36 inches having a third mass, wherein the first mass is less than the second mass and the second mass is less than the third mass, and wherein said first, second, and third golf club all have individual shafts that have a mass that satisfies the equation

[0009] These and other features, aspects and advantages of the present invention will become better understood with references to the following drawings, description and claims.

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BRIEF DESCRIPTION OF THE DRAWINGS

[0010] 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.

[0011] FIG. 1 of the accompanying drawing shows a perspective view of long-iron golf club shaft in accordance with an exemplary embodiment of the present invention;

[0012] FIG. 2 of the accompanying drawings shows a perspective view of a mid-iron golf club shaft in accordance with an exemplary embodiment of the present invention;

[0013] FIG. 3 of the accompanying drawings shows a perspective view of a short-iron golf club shaft in accordance with an exemplary embodiment of the present invention;

[0014] FIG. 4 of the accompanying drawings shows a perspective view of a long-iron, a mid-iron, and a short-iron shaft, all in accordance with an exemplary embodiment of the present invention, all next to one another; and

[0015] FIG. 5 of the accompanying drawings shows a perspective view of three golf clubs within a set of golf clubs complete with individual components such as the golf club head, the golf club shaft, and the golf club grip.

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DETAILED DESCRIPTION OF THE INVENTION

[0016] The following detailed description is of 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.

[0017] Various inventive features are described below that can each 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.

[0018] Due to the fact that one of the ways the present invention achieves the improvement in overall club performance improvements by adjusting the mass Μ_shaft of the golf club shaft as a function of the length L_shaft of the shaft, the discussion below will begin by focusing on the shaft portion of the golf club. However, because the overall performance of the golf club is what the present invention is ultimately focused on, the latter portion of this discussion will then shift to focus on the length I^M, of the golf club and the mass M_club of the golf club.

[0019] One of the ways to achieve the desired overall club mass is by adjusting the mass MskaftOf the shaft as the length L_shaft of the shaft changes. More specifically, the present invention creates a very specific relationship between the M^un and the L_shaft that creates an increase in the golf club mass Mdnft as the length L^R decreases.

[0020] FIG. 1 of the accompanying drawings shows a perspective view of a golf club shaft 100 of a long-iron in accordance with an exemplary embodiment of the present invention. The present invention, in order to improve the performance of a golf club via the golf club shaft 100, has created a specific relationship between a length L_shaft of the golf club shaft 100 as a function to the mass M_shaft of the golf club shaft 100. More specifically, the relationship created between the length L_shaft of the golf club shaft 100 and the mass of the golf club shaft 100 is inversed, meaning a decrease in the length Lehan of the golf club shaft 100 will equate to an increase in the mass Me_han of the golf club shaft 100. In one exemplary embodiment of the present invention, this inverse

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relationship between the length L_shaft and the mass Μ_shaft can be quantified by equation (1) below:

[0021] In one exemplary embodiment of the present invention, the long-iron golf club shaft 100 may have a length L_shaft of about 40.5 inches and mass M_shaft of greater than about 104 grams. In another exemplary embodiment of the present invention, the long- iron golf club shaft 100 may have a length L_shaft of about 40 inches and a mass M_shaft of greater than about 107 grams. In another exemplary embodiment of the present invention, the long-iron golf club shaft 100 may have a length L_shaft of about 39.5 inches and a mass M_shaft of greater than about 110 grams. In another exemplary embodiment of the present invention, the long-iron golf club shaft 100 may have a length L_shaft of about 39 inches and a mass M_shaft of greater than about 113 grams.

[0022] In order to achieve the relationship between shaft length L_shaft and mass above, the present invention utilizes different internal and external shaft profiles to help achieve this goal. In the current exemplary embodiment, section 101 may have an outer diameter of about 0.60 in, section 102 may have an outer diameter of about 0.59 in, section 104 may have an outer diameter of about 0.575 in, section 106 may have an outer diameter of about 0.56 in, section 108 may have an outer diameter of about 0.545 in, section 110 may have an outer diameter of about 0.530 in, section 112 may have an outer diameter of about 0.515 in, section 114 may have an outer diameter of about 0.500 in, section 116 may have an outer diameter of about 0.485 in, section 118 may have an outer diameter of about 0.470 in, section 120 may have an outer diameter of about 0.450 in, section 122 may have an outer diameter of about 0.430 in, section 124 may have an outer diameter of about 0.410 in, section 126 may have an outer diameter of about 0.395 in, and section 128 may have an outer diameter that tapers at a rate of about 0.0075 in/in until the shaft 100 reaches an outer diameter of about 0.355 inches.

[0023] Finally, it should be noted here that the outer profile of the golf club shaft 100 is stepped in its outer diameter profile, which can help provide the amount of mass adjustment needed for the current invention. However, the outer profiles of the golf club

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shaft 100 can be continuously tapered, parallel, or any other geometry or even alternate materials all without departing from the scope and content of the present invention.

[0024] FIG. 2 of the accompanying drawings shows a perspective view of a golf club shaft 200 of a mid-iron in accordance with an exemplary embodiment of the present invention. The mid-irons, similar to long-irons, have an inverse relationship between the length L_shaft and the mass M_shaft resulting in a similar relationship established above in Equation (1). In one exemplary embodiment of the present invention, the mid-iron golf club shaft 200 may have a length L_shaft of about 38.5 inches and mass M_shaft of greater than about 116 grams. In another exemplary embodiment of the present invention, the mid-iron golf club shaft 200 may have a length of about 38 inches and a mass M_shaft of greater than about 1 19 grams. In another exemplary embodiment of the present invention, the mid-iron golf club shaft 200 may have a length L_shaft of about 37.5 inches and a mass M_shaft of greater than about 122 grams.

[0025] In order to achieve the relationship between shaft length L_shaft and mass M_shaft above, the present invention may have a section 201 with an outer diameter of about 0.600 in, a section 202 with an outer diameter of about 0.585 in, a section 204 with an outer diameter of about 0.568 in, a section 206 with an outer diameter of about 0.553 in, a section 208 with an outer diameter of about 0.538 in, a section 210 with an outer diameter of about 0.523 in, a section 212 with an outer diameter of about 0.508, a section 214 with an outer diameter of about 0.493 in, a section 216 with an outer diameter of about 0.478 in, a section 218 with an outer diameter of about 0.463 in, a section 220 with an outer diameter of about 0.445 in, a section 222 with an outer diameter of about 0.430 in, a section 224 with an outer diameter of about 0.410 in, a section 226 with an outer diameter of about 0.395 in, and section 228 may have an outer diameter that tapers a rate of about 0.0075 in/in until the shaft 200 reaches an outer diameter of about 0.355 inches.

[0026] FIG. 3 of the accompanying drawings shows a perspective view of a golf club shaft 300 of a short-iron in accordance with an exemplary embodiment of the present invention. The short-irons, similar to long-irons and mid-irons, have an inverse relationship between the length L_shaft and the mass M_shaft resulting in a similar relationship established above in Equation (1). In one exemplary embodiment of the present invention, the short-iron golf club shaft 300 may have a length L_shaft of about

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37.0 inches and mass M_shaft of greater than about 125 grams. In another exemplary embodiment of the present invention, the short-iron golf club shaft 300 may have a length L_shaft of about 36.S inches and a mass M_shaft of greater than about 128 grams.

[0027] In order to achieve the relationship between shaft length L_shaft and mass M_shaft above, the present invention may have a section 301 with an outer diameter of about 0.S80 in, a section 302 with an outer diameter of about 0.560 in, a section 304 with an outer diameter of about 0.545 in, a section 306 with an outer diameter of about 0.530 in, a section 308 with an outer diameter of about 0.515 in, a section 310 with an outer diameter of about 0.500 in, a section 312 with an outer diameter of about 0.485, a section 314 with an outer diameter of about 0.470 in, a section 316 with an outer diameter of about 0.445 in, a section 318 with an outer diameter of about 0.440 in, a section 320 with an outer diameter of about 0.425 in, a section 322 with an outer diameter of about 0.410 in, a section 324 with an outer diameter of about 0.395 in, a section 226 with an outer diameter of about 0.395 in, and section 328 may have an outer diameter that tapers a rate of about 0.0075 in/in until the shaft 300 reaches an outer diameter of about 0.355 inches.

[0028] FIG. 4 of the accompanying drawings shows a perspective view of all three of the shafts discussed earlier, the long-iron shaft 100, the mid-iron shaft 200, and the short-iron shaft 300 next to one another for an illustration of the relative length of one another.

[0029] Finally, returning to the discussion regarding the golf club itself, FIG. 5 of the accompanying drawings shows a perspective view of all three golf club shafts 100, 200, and 300 being connected to their respective components. This illustration will bring the entire invention together in establishing a relationship between the overall club length L_shaft of the golf clubs 107, 207, and 307 and the overall club mass M_shaft can be established. It is important to establish the criticality of the discussion focusing on the overall club mass M_shaft as well as the overall club length L_shaft because that specific relationship is the one that controls performance. Returning to FIG.5 we can see that the overall club mass M_shaft as well as the overall club length L_shaft are all functions of three main components, the club head 103, 203 and 303, the shaft 100, 200, and 300, as well as the grip 105, 205, and 305. Taking into consideration of these components, the following relationship can be established as shown by Equation (2) below:

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[0030] In one exemplary embodiment of the present invention the golf clubs 107, 207, and 307 may have a length L_club of about 39 inches and mass M_club of greater than about 396 grams. In another exemplary embodiment of the present invention, invention the golf clubs 107, 207, and 307 may have a length L_shaft of about 38.5 inches and mass M_club of greater than about 405 grams. In another exemplary embodiment of the present invention, invention the golf clubs 107, 207, and 307 may have a length L_club of about 38 inches and mass M_club of greater than about 415 grams. In another exemplary embodiment of the present invention, invention the golf clubs 107, 207, and 307 may have a length L_club, of about 37.5 inches and mass M_club of greater than about 424 grams. In another exemplary embodiment of the present invention, invention the golf clubs 107, 207, and 307 may have a length L_club of about 37 inches and mass M_club of greater than about 435 grams. In another exemplary embodiment of the present invention, invention the golf clubs 107, 207, and 307 may have a length L_club of about 36.5 inches and mass M_club of greater than about 446 grams. In another exemplary embodiment of the present invention, invention the golf clubs 107, 207, and 307 may have a length L_club of about 36 inches and mass M_club of greater than about 456 grams. In another exemplary embodiment of the present invention, invention the golf clubs 107, 207, and 307 may have a length L_club of about 35.75 inches and mass M_club of greater than about 464 grams.

[0031] Based on the above, it can be seen that if you have a plurality of two or more of golf clubs in a set of golf clubs, there will be a relationship established between the mass M_club and the overall club length L_shaft such that the longer clubs will be lighter while the shorter clubs will be heavier. In addition to the above, although the above discussion is directed at a set of iron type golf clubs, this progressive relationship could be applied across an entire set of golf clubs from a driver of up to 48 inches down to a putter down to 32 inches, all without departing from the scope and content of the present invention.

[0032] It should be noted that although the dominant contributor to the adjustment in overall club mass M_club and the overall club length L_club may be the shaft mass M_shaft and the shaft length L_shaft. the other components are just as important in contributing in creating the relationship articulated above in Equation (2). In fact, adjustments could be made to the club head 103, 203 and 303 as well as the grip 105, 205, and 305 to achieve

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the relationship articulated above in Equation (2) without departing from the scope and content of the present invention.

[0033] Alternatively, it can be said that the present invention relates to a plurality of golf clubs having a first golf club having a length greater than 38 inches, a second golf club having a length of between about 36 to 38 inches, and a third golf club having a length less than about 36 inches. The first golf club will generally have the lightest mass with a first mass, while the second golf club will generally have a mass that is heavier than the first mass, with the third golf club having a third mass, which is greater than the first mass and the second mass. Ultimately, the specific relationship created between the mass and the length of the golf club is beneficial in helping improve the performance of the golf club, despite its counter-intuitive nature. Generally speaking, when a golf club is shorter, the mass of the golf club shaft decreases when a uniform material shaft is trimmed. This antiquated wisdom leaves the golf club shaft to be heaviest at higher lofts and lighter at lower lofts. The present invention improves upon this methodology by reversing the conventional thinking with a more performance based design approach. In order to help golfers swing the longest golf club in their bag the best, it is beneficial to help reduce the mass of the golf club in those longer clubs, which ultimately results in an increase in the mass of the shorter irons. The present invention takes advantage of that unconventional methodology and has created a very specific relationship for those variable.

[0034] 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 preceding 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

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parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0035] 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.

[0036] 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.

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Claims

Attorney Docket No. 9808-380-POA CLAIMS WHAT IS CLAIMED IS:

1. A golf club comprising:

a club head located at a distal end of said golf club;

a grip located at a proximal end of said golf club; and

a shaft, juxtaposed between said club head and said grip, connecting said club head to said grip;

wherein a mass M_club of said golf club decreases with an increase in a length L_club of said golf club in accordance with the relationship, M_club > -20.691 L_club + 1201.5.

2. The golf club of claim 1 , wherein said shaft is stepped.

3. The golf club of claim 1 , wherein a mass M_shaft of said shaft decreases with an increase in a length L_shaft of said shaft in accordance with the relationship,

M_shaft > -6 L_shaft + 347.

4. The golf club of claim 3, wherein said length of said golf club L_club between 32 inches and 48 inches.

5. A plurality of golf clubs comprising:

a first golf club having a length L_club of greater than about 38 inches having a first mass,

a second golf club having a length L_club of between about 36 inches to about 38 inches having a second mass, and

a third golf club having a length L_club of less than about 36 inches having a third mass,

wherein said first mass is less than said second mass and said second mass is less than said third mass; and

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wherein said first, second, and third golf club all have individual shafts that have a mass that satisfies the equation M_shaft > -6 L_shaft + 347.

6. The plurality of golf clubs of claim 5, wherein said first mass is less than about 415 grams.

7. The plurality of golf clubs of claim 6, wherein said second mass is between about 415 grams and about 446 grams.

8. The plurality of golf clubs of claim 7, wherein said third mass is greater than about 446 grams.

9. The plurality of golf clubs of claim 5, wherein said first mass, said second mass, and said third mass are all a function of said length of said first, second, or third golf club in accordance with the relationship, M_club≥ -20.691 L_club + 1201.5.

10. The plurality of golf clubs of claim 9, said shaft is stepped.

1 1. The plurality of golf clubs of claim 9, wherein said first golf club further comprises a first shaft, said first shaft has 15 sections; wherein each section has a decrease in outer diameter.

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