Patent Application
20240091603
This invention relates to golf club heads, and in particular, abrasion resistant material applied to the striking face.
In order to improve the performance of a golf club, golf club designers have constantly struggled with finding different golf club configurations that can hit a golf ball longer and straighter. Designing a golf club that hits a golf ball longer may generally require an improvement in the ability of the golf club head to effectively transfer the energy generated by the golfer onto a golf ball via the golf club. Hitting a golf ball straighter, on the other hand, will generally require an improvement in the ability of the golf club to keep the golf ball on a relatively straight path even if the golf ball is struck off-center; as a golf ball that is struck at the center of the golf club head will generally maintain a relatively straight flight path.
Effectively transferring the energy generated by the golfer onto a golf ball in order to hit a golf ball further may be largely related to the Coefficient of Restitution (COR) between the golf club and the golf ball. The COR between a golf club and a golf ball may generally relate to a fractional value representing the ratio of velocities of the objects before and after they impact each other. U.S. Pat. No. 7,281,994 to De Shiell et al. provides one good example that explains this COR concept by discussing how a golf club head utilizing a thinner striking face may deflect more when impacting a golf ball to result in a higher COR; which results in greater travel distance.
Being able to hit a golf ball relatively straight even when the club strikes a golf ball at a location that is offset from the center of the striking face may generally involve the ability of the golf club to resist rotational twisting; a phenomenon that occurs naturally during off-center hits. U.S. Pat. No. 5,058,895 to Igarashi goes into more detail on this concept by discussing the advantages of creating a golf club with a higher Moment of Inertia (MOI), which is a way to quantify the ability of a golf club to resist rotational twisting when it strikes a golf ball at a location that is offset from the geometric center of the golf club head. More specifically, U.S. Pat. No. 5,058,895 to Igarashi utilizes weights at the rear toe, rear center, and real heel portion of the golf club head as one of the ways to increase the MOI of the golf club head, which in turn allows the golf club to hit a golf ball straighter. It should be noted that although the additional weights around the rear perimeter of the golf club head may increase the MOI of the golf club, these weights cannot be added freely without concern for the overall weight of the golf club head. Because it may be undesirable to add to the overall weight of the golf club head, adding weight to the rear portion of the golf club head will generally require that same amount of weight to be eliminated from other areas of the golf club head.
Based on the two above examples, it can be seen that removing weight from the striking face of the golf club head not only allows the golf club head to have a thinner face with a higher COR, the weight removed can be placed at a more optimal location to increase the MOI of the golf club head. One of the earlier attempts to remove unnecessary weight from the striking face of a golf club can be seen in U.S. Pat. No. 5,163,682 to Schmidt et al. wherein the striking face of a golf club head has a variable thickness by making the part of the striking face that is not subjected to the direct impact thinner.
U.S. Pat. No. 5,425,538 to Vincent et al. shows an alternative way to remove unnecessary weight from the striking face of a golf club by utilizing a fiber-based composite material. Because fiber-based composite materials may generally have a density that is less than the density of traditional metals such as steel or titanium, the simple substitute of this fiber-based composite material alone will generate a significant amount of discretionary weight that can be used to improve the MOI of a golf club. Fiber-based composite materials, because of their relatively lightweight characteristics, tend to be desirable removing weight from various portions of the golf club head. However, because the durability of such a lightweight fiber-based composite material can be inferior compared to a metallic type material, completely replacing the striking face of a golf club with the lightweight fiber-based composite material could sacrifice the durability of the golf club head.
U.S. Pat. No. 7,628,712 to Chao et al. discloses one way to improve the durability of striking face made out of a fiber-based composite material by using a metallic cap to encompass the fiber-based composite material used to construct the striking plate of the golf club head. The metallic cap aids in resisting wear of the striking face that results from repeated impacts with a golf ball, while the rim around the side edges of the metallic ring further protects the composite from peeling and delaminating. The utilization of a metallic cap, although helps improve the durability of the striking face of the golf club head, may not be a viable solution, as severe impact could dislodge the fiber-based composite from the cap.
In addition to the durability concerns of the fiber resin matrix itself, utilizing composite materials to form the striking face of a golf club offers additional challenges. More specifically, one of the major design hurdles arises when a designer attempts to bond a fiber-based composite material to a metallic material, especially at a location that is subjected to high stress levels normally generated when a golf club hits a golf ball. Finally, the usage of composite type materials to form the striking face portion of the golf club head may also be undesirable because it alters the sound and feel of a golf club away from what a golfer are accustomed to, deterring a golfer from such a product.
Ultimately, despite all of the attempt to improve the performance of a golf club head by experimenting with alternative face materials, the prior art lacks a way to create a striking face that saves weight, improves COR, and is sufficiently durable without sacrificing the sound and feel of the golf club head. Hence, as it can be seen from above, there is a need in the field for a golf club head having a fiber based composite striking face that can save weight, improve the COR of the golf club head, and can endure the high stress levels created by the impact with a golf ball, all without sacrificing the sound and feel of the golf club head.
The present invention is directed to improving the abrasion resistance of the striking face of a golf club head without compromising COR or generating unnecessary weight in the club head by applying abrasion resistant material to the striking face. Abrasion resistant material can be applied to the striking face by treating, coating, layering or otherwise, integrating the abrasion material onto the striking face. In one aspect of the present invention, abrasion material can be applied to the golf club striking face by electroplating with a metal, such as chromium. A physical vapor deposition can further be applied to the electroplated striking face.
In another embodiment of the present invention, a veil can be applied to the striking face by co-molding the veil to a composite striking face. The veiled striking face can optionally be further electroplated with a metal, such as chromium. A physical vapor deposition can then be applied to the veiled, electroplated striking face.
In another embodiment of the present invention, a single veil or a combination of veils can be applied directly to the striking face with our without further treatment. The veil can comprise compounds, such as aramid, polyetherimide (PEI), polyphenylene sulfide (PPS), polyetheretherketone (PEEK), metals, such as copper, carbon, such as carbon nanotubes, and the like, and any combination thereof.
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 detailed description set forth below in connection with the appended drawings is intended as a description of presently-preferred embodiments of the invention and is not intended to represent the only forms in which the present invention may be constructed or utilized. The description sets forth the functions and the sequence of steps for constructing and operating the invention in connection with the illustrated embodiments. It is to be understood, however, that the same or equivalent functions and sequences may be accomplished by different embodiments that are also intended to be encompassed within the spirit and scope of the invention.
For ease of description, the striking face portion will be referred to as the front side of the golf club head 100. As such, the striking face 102 is located at a frontal portion of the golf club head 100. As a result, the back portion 114 is located opposite the striking face portion 112; the topline 104 is located at an upper portion of the golf club head 100; the heel portion 108 is located at a proximal end of the golf club head 100; the toe portion 106 is located at a distal end of the golf club head 100 opposite the heel portion 108; and the sole 102 is located at a lower portion of the golf club head 100 opposite the topline 104. An axis of origin 12 is provided (for reference only for ease and clarity of description) indicating the x-y-z direction relative to the golf club head 100 in the examples provided.
The leading edge 120 can be defined in the current application as approximately the most forward edge of the golf club head 100, with the hosel 110 in an upright 90 degree (perpendicular) position from a ground plane 10 (in the front-to-back, z-axis direction). (The ground plane 10 is an imaginary plane located and in contact with the lowest portion of the golf club head 100, and mimics the surface of the ground upon which the golf ball would lie.) This leading edge 120 is then defined as approximately the forward most edge along the z-axis (as indicated by the axis of origin 12) generally where the striking face 112 meets the sole 102. In addition to illustrating the leading edge 120,
The invention of the present application incorporates improvements to the striking face 112 that dramatically improves abrasion resistance of the golf club head 100 without adding substantial weight to the golf club head 100 by applying abrasion resistant material to the striking face 112. Preferably, the striking face 112 is a composite material.
In some embodiments, the striking face 112 can be integrally formed with the body 101 as a single piece. In the preferred embodiment, the striking face 112 is in the form of an insert, as shown in
In the preferred embodiment, the insert for the striking face 112 can comprise resin composites. By way of example only, the insert can comprise thermoplastic resin, such as thermoplastic polyetherimide (PEI) made by Stratasys under the trademark ULTEM™. In some embodiments, the striking face 112 can comprise a unidirectional carbon fiber layup to reduce the weight of the insert. In some embodiments, striking face 112 can comprise a thermoset carbon fiber composite. In the preferred embodiment, the remainder of the body 101 can be a steel body. In some embodiments, the body 101 can be made of other traditional materials used for golf clubs.
In the present invention, an abrasion resistant material can be applied to the striking face 112 that result in the abrasion resistant material being coated, treated, layered, or otherwise integrated onto the striking face. In some embodiments, the abrasion resistant material can be applied to the striking face 112 of the golf club head 100 using an electroplating technique to create a plated layer 140. Preferably, the plating process comprises chromium, resulting in a chrome plated striking face 112. Standard electroplating techniques can be used. By way of example only, the striking face 112 can be placed in an electrolytic cell having an electrolytic solution, an anode, and a cathode. A DC battery can be connected to the anode and the cathode. The striking face 112 can function as the cathode or be connected to the cathode, and the metal used to plate the striking face 112, such as chromium, can function as the anode or be connected to the anode. The electrolytic solution can be a salt of the metal that is being used for the plating. When the battery is turned on, the metal ions from the anode travel through the electrolytic solution to the striking face 112 creating a thin plated layer 140 of plating on the striking face 112. In some embodiments, the plating layer 140 can be applied directly to the striking face 112. In other embodiments, as shown in
For example, a veil 142 can be applied to the composite striking face 112 by co-molding the composite striking face 112 with the veil 142. Preferably, the veil 142 is a conductive veil. More preferably, the veil 142 is a carbon veil or a glass veil. In embodiments with a veil 142, the plating can be applied directly to the veil 142. An example of a carbon veil is the Optiveil® manufactured by Technical Fibre Products Inc. Having a conductive veil co-molded with the striking face 112 enables the plating, and in particular, chrome plating, to better adhere to the surface of the striking face 112. This technique results in a very thin veil layer 142 having a thickness from about 0.05 mm to about 0.40 mm. In addition, the areal weight can be about 4 g/m2 to about 34 g/m2. In some embodiments, the thickness of the veil can be about 0.12 mm to about 0.20 mm with an areal weight of about 0.3 g/m2 to about 0.5 g/m2. In some embodiments, the thickness of the veil can be about 0.17 mm with an areal weight of about 0.4 g/m2. By contrast, using an injection molding resin onto which chrome plating can be applied results in a resin layer that is over 1 mm.
In some embodiments, the veil 142 can be applied to the striking face 112 with a coating comprising aramid, polyetherimide (PEI), polyphenylene sulfide (PPS), polyetheretherketone (PEEK), metals such as copper, carbon such as carbon nanotubes, or the like, or any combination thereof. For example, in one embodiment, a carbon nanotube coating can be applied for aesthetics, and a PEI or PPS coating can be applied for improved abrasion resistance. In some embodiments, the veil coating can be applied directly to the striking face 112.
In some embodiments, the golf club head 100 comprises a physical vapor deposition (PVD) layer 144 applied to the striking face 112. By way of example only, the striking face 112 can be placed in a chamber with a source material, generally in solid form. Energy can be applied to the source material to produce metal vapors from the source material. The vapor then travels within the chamber and condenses on the striking face 112 creating a thin layer of the vapor deposition on the striking face 112. The chamber is generally in a vacuum state, and can be back-filled with other gases (nitrogen, oxygen, methane, argon, and the like, and any combination thereof) to create the desired properties or appearance on the striking face 112. The energy applied to the source material can be from a cathodic arc source (e.g., plasma energy), magnetron sputtering (thermal energy), or other known energy sources used in PVD. Energy, such as from a DC power supply, can also be applied to the striking face 112 to charge the striking face 112 to improve the attraction of the metal vapors to the striking face 112. The PVD layer 144 can be applied directly to the striking face 112, to a plated layer 140, or to a veil 142.
As such, the striking face 112 can be electroplated to create a plated layer 140 directly on the striking face 112, co-molded with a veil 142 then electroplated, coated with a veil 142 and electroplated to add a plated layer 140, and in any of the aforementioned embodiments, treated further with physical vapor deposition.
In some embodiments, any abrasion resistant material disclosed herein (i.e., plating, veils, and physical vapor depositions), alone or in any combination, can be applied to the striking face 112 only, applied to the striking face 112 and the sole 102, or applied to the striking face 112 and the entire body 101.
Because the improved abrasion of the golf club head is so critical to the present invention,
Before the testing begins, the Abraser 350 is set at a predetermined preset speed of 25 cycles per minute via the Preset Speed Buttons 352 on the Abraser 350. Once the speed is set to the appropriate speed of 25 cycles per minute, the base load of the Abraser 350 is set to approximately 350 grams, as the base load will affect the amount of abrasion that is applied by the Abraser 350. In this current exemplary embodiment, to achieve the base load of approximately 350 grams, 3 different components are attached to the distal end of a movement arm 353 to create the load weight. More specifically, a weight support 354 is selected to have a mass of about 167 grams, a spline shaft 356 is selected to have a mass of about 85 grams, and a weraser collet 358 is selected to have a mass of about 98 grams, all connecting to the movement arm 353 as shown in
Once the speed of the Abraser 350 is set and the base load of the Abraser 350 is established above, the feet 360 of the Abraser 350 are adjusted to make sure the entire Abrasaer 350 is level with the air bubble in the center of the indicator. Subsequent to the leveling of the Abraser 350, the wearaser 362 is inserted to the bottom of the collet kit 358 to prepare the Abraser 350 for engaging a golf club head. In this testing procedure, the wearaser 362 is a Taber® CS-17 Calibrase abrasive wheel for Taber® industries, bearing part number 125322, having a medium-coarse abrading action. The wearaser 362 is installed so that it extends 0.100 inch from the bottom of the collet 358.
Subsequent to the installation of the wearaser 362, the stroke length of the Abraser 302 is set to a 0.5 inch using the stroke length adjuster 364, which is attached to the proximal end of the movement arm 353. The stroke length adjuster 364 in the Abraser 302 is protected by a cover 366 which opens to reveal the stroke length adjuster 364. The stroke length adjuster 364 converts the rotational movement of the Abraser 302 into a translational movement of the movement arm 353 to conduct the testing.
Once the stroke length of the Abraser 350 is set, the golf club can be fixtured to the Abraser 350 to begin testing.
A golf club head in accordance with an exemplary embodiment of the present invention may generally have a Thickness to Abrasion Count Ratio of less than about 0.4, more preferably less than about 0.1, even more preferably less than about 0.025, and most preferably less than about 0.005. The Thickness to Abrasion Count Ratio defined by Eq. (1) below:
Applying the test described above on striking surfaces 112 comprising aramid, PEI, PPS, PEEK, copper, or carbon coating, in particular, passed the abrasion test. The current golf club head 100 containing the abrasion resistant material disclosed herein, in addition to all the benefits discussed above, may also exhibit an improved Characteristic Time (CT) to COR relationship. More details about the CT to COR relationship can be found in the discussion relating to CT slope found in U.S. Patent Publication No. 2022/0227028 to Deshmukh et al., the disclosure of which is incorporated by reference in its entirety.
The foregoing description of the preferred embodiment of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of the above teaching. It is intended that the scope of the invention not be limited by this detailed description, but by the claims and the equivalents to the claims appended hereto.
