Patent Grant
10653930
Not Applicable
The present invention relates to a golf club head. More specifically, the present invention relates to an iron-type golf club head comprising a novel polymeric fill material that improves the sound of the club head without significantly reducing the golf club head's ball speed or coefficient of restitution. The fill material is preferably co-molded with a metal slug that is disposed within the golf club head to lower the center of gravity of the golf club head.
Golf club heads, and particularly iron-type golf club heads, often include polymeric materials disposed behind the striking face to improve or dampen the sound of the head upon impact with a golf ball. For example, U.S. Pat. No. 5,492,327 discloses an iron with a damping material in a recess, U.S. Pat. No. 6,743,117 discloses a dampening insert behind a strike face insert in an iron, and U.S. Pat. No. 9,168,437 discloses an elastomeric insert attached to the back of the striking face of an iron. Unfortunately, while a polymer fill or insert can improve the sound of the golf club in which it is disposed, this configuration reduces ballspeed off the face, as well as the coefficient of restitution (COR) of the golf club head. This occurs because polymers such as urethane are rigid, with a Poisson's ratio of around 0.5, and when a polymer fills a cavity or space, the polymer prevents the golf club face from flexing. Therefore, there is a need for a golf club head comprising an improved fill material that also preserves, or otherwise optimizes, ballspeed and COR values.
The golf club head comprises a novel fill material comprising microscopic bubbles (also referred to as hollow beads) made from a strong, lightweight, low-density material such as glass, ceramic, and/or plastic, mixed with a polymeric material, preferably urethane or silicone, at least partially filling a cavity within the club head or affixed to a portion of the club head in medallion form. The presence of the microscopic bubbles in the polymeric material prevents the COR of the golf club head from decreasing by more than 0.10, and more preferably by more than 0.05, when compared with a golf club head having all of the same features and characteristics but which lacks a polymeric fill material completely.
One aspect of the present invention is a golf club head, such as an iron, putter, driver, fairway wood, or wedge, comprising a body comprising a striking face, sole portion, top portion, rear portion, and cavity, and a fill material at least partially filling the cavity, wherein the fill material comprises a first material and a plurality of microscopic bubbles composed of a second material, wherein the first material is a polymer and wherein the second material is different from the first material, and wherein the plurality of microscopic bubbles constitutes 5% to 70% of a volume of the fill material. In some embodiments, the polymer material may be selected from the group consisting of polyurethane and silicone. In other embodiments, wherein the second material may be selected from the group consisting of glass, ceramic, and plastic. In still other embodiments, the plurality of microscopic bubbles may constitute at least 20% of the volume of the fill material, and in a further embodiment, 25-30% of the volume of the fill material. In still other embodiments, the polymer material may have a Poisson's ratio of 0.00-0.50, and more preferably 0.40-0.50. In still other embodiments, when a central area of the striking face impacts a golf ball, the golf club head may have a pitch of 3000-6000 Hz, an amplitude of 90-100 dB, a duration of 1-2.5 ms, and a ball speed of at least 112.5 mph. In still other embodiments, the fill material may be a medallion affixed to a rear surface of the striking face.
Another aspect of the present invention is a method comprising the steps of providing a golf club head comprising a body having at least one cavity, providing a polymer material, providing a plurality of microscopic bubbles composed of a low-density material, combining the plurality of microscopic bubbles with the polymer material to create a fill material, and injecting the fill material into the at least one cavity of the golf club head, wherein the plurality of microscopic bubbles constitutes 5-70% of a volume of the fill material. In some embodiments, the plurality of microscopic bubbles may constitute approximately 25-30% of the volume of the fill material. In other embodiments, the polymer material may be selected from the group consisting of polyurethane and silicone, the low-density material may be composed of a material selected from the group consisting of glass, ceramic, and plastic.
Yet another aspect of the present invention is a method comprising the steps of providing a golf club head comprising a body having at least one cavity, providing a polymer material, providing an agent material selected from the group consisting of a curative and a catalyst, providing a plurality of microscopic bubbles composed of a material selected from the group consisting of glass, ceramic, and plastic, combining the plurality of microscopic bubbles with the agent material to create an intermediary material, combining the intermediary material with the polymer material to create a fill material, and injecting the fill material into the at least one cavity of the golf club head, wherein the plurality of microscopic bubbles constitutes 5-70% of a volume of the intermediary material. In some embodiments, the plurality of microscopic bubbles may be combined with the agent material at a 5:3 ratio, and the fill material may comprise a 1:1 ratio of polymer material and intermediary material. In other embodiments, the plurality of microscopic bubbles may constitute approximately 20-30% of the volume of the intermediary material. In still other embodiments, the polymer material may have a Poisson's ratio of 0.40-0.50 and be selected from the group consisting of polyurethane and silicone. In one embodiment, the golf club head may be an iron-type golf club head comprising a body having a striking face, a sole portion, a top portion, and a rear portion, the at least one cavity may be disposed between the striking face and the rear portion, and the fill material may completely fill the at least one cavity. In a further embodiment, the method may comprise the step of curing the golf club head in an oven after the step of injecting the fill material into the at least one cavity of the golf club head.
Another aspect of the present invention is a method comprising the steps of providing a golf club head comprising a body having at least one cavity, providing a polymer material having a Poisson's ratio of 0.40-0.50, providing an agent material selected from the group consisting of a curative and a catalyst, providing a plurality of microscopic bubbles composed of a material selected from the group consisting of glass, ceramic, and plastic, combining the polymer material with the agent material to form an intermediary material, combining the plurality of microscopic bubbles with the intermediary material to create a fill material, injecting the fill material into the at least one cavity of the golf club head, and curing the fill material within the golf club head, wherein the plurality of microscopic bubbles constitutes 5-70% of a volume of the fill material. In some embodiments, the golf club head may be an iron-type golf club head, the plurality of microscopic bubbles may constitute approximately 20-30% of the volume of the fill material, and the polymer material may be selected from the group consisting of polyurethane and silicone.
Yet another aspect of the present invention is a golf club head comprising a body comprising a striking face, sole portion, top portion, rear portion, and cavity, a metal weight, and a fill material comprising a first material and a plurality of microscopic bubbles composed of a second material, wherein the second material is different from the first material, wherein the metal weight is disposed within the cavity, wherein the fill material at least partially envelops the metal weight and at least partially fills the cavity, and wherein the plurality of microscopic bubbles constitutes 5% to 70% of a volume of the fill material. In some embodiments, the first material may be selected from the group consisting of polyurethane and silicone. In other embodiments, the second material may be selected from the group consisting of glass, ceramic, and plastic, and each of the plurality of microscopic bubbles may have a diameter of approximately 18-50 microns. In still other embodiments, the plurality of microscopic bubbles may constitute at least 20% of the volume of the fill material, such as 25-30% of the volume of the fill material. In other embodiments, the polymer material may have a Poisson's ratio of 0.00-0.50, and more specifically, 0.40-0.50. In still other embodiments, the metal weight may be composed of tungsten alloy, and the fill material may completely envelop the metal weight. In another embodiment, a combination of the metal weight and the fill material may completely fill the cavity. In any of these embodiments, the golf club head may be an iron-type golf club head.
Another aspect of the present invention is a method method comprising the steps of providing a golf club head comprising a body having a cavity, providing a metal weight, providing a fill material comprising a polymer material and a plurality of microscopic bubbles composed of a low-density material, injection-molding the fill material onto the metal weight to create a co-molded weight, and inserting the co-molded weight into the cavity. In some embodiments, the plurality of microscopic bubbles may constitute approximately 25-30% of the volume of the fill material. In another embodiment, the polymer material may be selected from the group consisting of polyurethane and silicone, and the low-density material may be composed of a material selected from the group consisting of glass, ceramic, and plastic. In a further embodiment, the golf club head may be an iron-type golf club head comprising a body having a striking face, a sole portion, a top portion, and a rear portion, the at least one cavity may be disposed between the striking face and the rear portion, and a combination of the metal weight and the fill material may completely fill the at least one cavity.
Yet another aspect of the present invention is a method comprising the steps of providing a golf club head comprising a body having a cavity, providing a metal weight, providing a fill material comprising a polymer material and a plurality of microscopic bubbles composed of a low-density material, inserting the metal weight into the cavity, and injection-molding the fill material into the cavity and around at least a portion of the metal weight. In some embodiments, the polymer material may be selected from the group consisting of polyurethane and silicone, and the low-density material may be selected from the group consisting of glass, ceramic, and plastic. In a further embodiment, the plurality of microscopic bubbles may constitute 25-30% of the volume of the fill material, and each of the plurality of microscopic bubbles may have a diameter of approximately 18-50 microns. In any of the embodiments, the metal weight may be composed of a metal alloy having a density of greater than 4 g/cc.
Having briefly described the present invention, the above and further objects, features, and advantages thereof will be recognized by those skilled in the pertinent art from the following detailed description of the invention when taken in conjunction with the accompanying drawings.
The present invention is directed to golf club heads, and particularly iron-type golf club heads, which include a novel fill material comprising a polymeric material and a plurality of microscopic bubbles made of glass, ceramic, and/or plastic, also referred to herein as microscopic, hollow beads. The microscopic bubbles serve two purposes when incorporated with a polymeric material: (1) they lighten the overall fill weight by replacing elastomer with air, thus lowering the material's specific gravity; and (2) they increase the porosity of the fill material, allowing for the formation of micro-holes in the polymeric material. The micro-holes are little air pockets that allow the polymer to flex when the club head impacts a golf ball, thus increasing the COR of the head while at the same time maintaining the sound improvement provided by the polymer itself, such as reduction in dB level and duration. The polymeric material preferably is an elastomer such as polyurethane or silicone having a Poisson's ratio of 0.00-0.50, and more preferably 0.40-0.50, and the microscopic bubbles preferably are measured in D50 micron, which is the median particle size for a measured sample, each microscopic bubble having a diameter of approximately 18-50 microns.
A preferred embodiment of the golf club head is shown in
In an alternative embodiment, shown in
In yet another embodiment, shown in
In each of the embodiments disclosed herein, the microscopic bubbles in the novel fill material 50 preferably constitute 5% to 70% by volume of the fill material 50, more preferably at least 20% of the volume, and most preferably approximately 25-30% of the fill material's 50 volume.
There are several methods of manufacturing the microscopic bubble fill material 50 and incorporating it into the golf club head 10 according to the present invention. The first method 100, shown in
The second, preferred method 200, shown in
The third method of the present invention is shown in
In order to assess the COR performance of the inventive material, test iron-type golf club heads 10 having unfilled (empty) cavities were created and tested, and compared against golf club heads 10 having the same construction and filled with (1) the novel microscopic bubble fill material 50 comprising polyurethane and glass bubbles and made using one of the second 200 and third methods 300 and (2) polyurethane only. As shown in Tables 1 and 2, the polyurethane-only fill significantly lowers the COR of the golf club head 10. In contrast, when a golf club head cavity is filled with the microscopic bubble fill material 50 (glass) of the present invention, the COR decreases, on average, only by 0.04, thereby retaining the performance benefits of an unfilled golf club head 10. This is particularly evident when the microscopic bubbles or hollow microscopic beads constitute approximately 25% or 30% of the volume of the fill material 50, as shown in Table 1.
In order to assess sound performance, another group of test golf club heads 10 incorporating the 30% by volume novel microscopic bubble fill material 50 comprising polyurethane and glass bubbles, and made using one of the second 200 and third methods 300 were tested and compared with golf club heads 10 having: (1) the same construction and filled with only polyurethane; (2) no polyurethane filler at all; and (3) a small polyurethane snubber insert. As shown in
To assess the effects of the novel fill material on ball speed performance, the performance of a Callaway Golf Apex CF 16 6-iron comprising a small polymeric snubber was compared with the performance of test 6-irons having no fill, test 6-irons with a fill having 30% by volume microscopic bubbles (glass material), and test 6-irons with a fill having 20% by volume microscopic bubbles (glass material). As shown in
In yet another embodiment of the present invention, shown in
The embodiment shown in
From the foregoing it is believed that those skilled in the pertinent art will recognize the meritorious advancement of this invention and will readily understand that while the present invention has been described in association with a preferred embodiment thereof, and other embodiments illustrated in the accompanying drawings, numerous changes, modifications and substitutions of equivalents may be made therein without departing from the spirit and scope of this invention which is intended to be unlimited by the foregoing except as may appear in the following appended claims. Therefore, the embodiments of the invention in which an exclusive property or privilege is claimed are defined in the following appended claims.
The present application is a continuation of U.S. patent application Ser. No. 15/927,917, filed on Mar. 21, 2018, and issued on Jan. 8, 2019, as U.S. Pat. No. 10,173,108, which is a continuation-in-part of U.S. patent application Ser. No. 15/807,851, filed on Nov. 8, 2017, and issued on Aug. 21, 2018, as U.S. Pat. No. 10,052,535, which is a continuation-in-part of U.S. patent application Ser. No. 15/718,285, filed on Sep. 28, 2017, and issued on Aug. 7, 2018, as U.S. Pat. No. 10,039,964, which is a division of U.S. patent application Ser. No. 15/665,004, filed on Jul. 31, 2017, and issued on Nov. 7, 2017, as U.S. Pat. No. 9,808,685, which claims priority to U.S. Provisional Patent Application No. 62/457,086, filed on Feb. 9, 2017, the disclosure of which is hereby incorporated by reference in its entirety herein.
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|---|---|---|---|
| 4650626 | Kurokawa | Mar 1987 | A |
| 4824110 | Kobayashi | Apr 1989 | A |
| 5007643 | Okumoto | Apr 1991 | A |
| 5465969 | Cadorniga | Nov 1995 | A |
| 5507985 | Cadorniga | Apr 1996 | A |
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| 8206239 | Gilbert | Jun 2012 | B2 |
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| 20080058117 | Roach | Mar 2008 | A1 |
| Number | Date | Country | |
|---|---|---|---|
| 20190255399 A1 | Aug 2019 | US |
| Number | Date | Country | |
|---|---|---|---|
| 62457086 | Feb 2017 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 15665004 | Jul 2017 | US |
| Child | 15718285 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 15927917 | Mar 2018 | US |
| Child | 16241859 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 15807851 | Nov 2017 | US |
| Child | 15927917 | US | |
| Parent | 15718285 | Sep 2017 | US |
| Child | 15807851 | US |
