The present invention relates to an improved method for producing a golf club head, and more particularly to an improved method of producing a club head made of a carbon fiber composite.
A wood-type golf club typically includes a hollow shaft with a club head attached to the lower end of the shaft. The club head typically includes a load-bearing outer shell with an integral or attached strike plate. The strike plate defines a substantially planar front surface or strike face for striking a golf ball.
A recent trend in the industry is to make the club head out of strong, yet lightweight material, such as, for example, titanium, a titanium alloy or a carbon fiber composite. Of these materials, carbon fiber composites are particularly interesting to golf club designers because it has a density that is roughly one third of the density of titanium but is almost as strong as titanium. Accordingly, carbon fiber composites are particularly suitable for very large club heads (i.e., club heads that define an internal volume greater than 400 centimeters cubed).
Despite their low density and strength, club heads that are made entirely of carbon fiber composites are generally not popular. This is due, in part, to the relatively high stiffness that is typical of carbon fiber composites. Such stiffness usually is undesirable especially in the strike plate. Moreover, carbon fiber composites are not particularly durable. Thus, composite club heads have a tendency to wear out in the areas that are subjected large amounts of wear and friction (e.g., the sole of the club head).
To overcome some of these problems, it has been suggested that the club head be made from a combination of titanium or alloy and carbon fiber composites. Specifically, it has been suggested that a club head can be formed from an outer shell made of a carbon fiber composite, which is attached to a strike plate made of a titanium or a titanium alloy. However, existing methods for manufacturing such a club have not been satisfactory. For example, one golf club manufacturer attempted to co-cure a metal strike plate with a composite outer shell. More specifically, a metal strike plate was placed in a mold along with an inflatable bladder that was surrounded by a uncured composite material. To cure the composite, the bladder was inflated to press the uncured material against the mold and the strike plate. However, fitting the strike face into mold and removing the bladder from the cured club head was difficult and time consuming.
An aspect of the present invention is an improved method for producing a club head comprising of a metal strike plate and a composite shell. A further aspect of the present invention is the realization that such a club can be produced by attaching the metal strike plate to the composite shell after the composite shell is formed. However, for the metal strike plate to be successfully attached to the strike plate the composite shell must be produced in a manner that ensures tight tolerances and smooth surfaces on both the inside surfaces and outside surfaces of the shell.
Accordingly, one aspect of the invention is a method for forming a golf club head. The method comprises placing an uncured composite material between a core and a mold that comprises a first piece and a second piece. The second piece is moved towards the first piece such that the uncured composite material is compressed between the core and at least a portion of the mold. The uncured composite material is heated. A first portion of the golf club head is removed from the mold. A second portion of the golf club head is provided. The first portion is attached to the second portion.
Another aspect of the invention is a method for forming a golf club head. The method comprises placing an uncured composite material between a core and a mold that comprises a first piece and a second piece. The second piece is moved towards the first piece such that the uncured composite material is compressed between the core and at least a portion of the mold. The uncured composite material is heated. A first mating section is formed on the first portion. A first portion of the golf club head is removed from the mold. A second portion of the golf club head is provided. The first portion is attached to the second portion.
Yet another aspect of the invention is a golf club head comprising a shell made of a composite material that is attached to a strike plate that is formed of a metallic material. The shell includes a first mating section and the strike plate including a second mating section configured to mate with the first mating section.
Still yet another aspect of the present invention is a golf club head comprising a shell made of a composite material that is attached to a strike/sole plate combination. The strike/sole plate combination includes strike plate and sole plate, which are integrally formed and made of a metallic material. The shell includes a first mating section and the strike/sole plate combination includes a second mating section configured to mate with the first mating section.
For purposes of summarizing the invention and the advantages achieved over the prior art, certain objects and advantages of the invention have been described herein above. Of course, it is to be understood that not necessarily all such objects or advantages may be achieved in accordance with any particular embodiment of the invention. Thus, for example, those skilled in the art will recognize that the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objects or advantages as may be taught or suggested herein.
All of these embodiments are intended to be within the scope of the invention herein disclosed. These and other embodiments of the present invention will become readily apparent to those skilled in the art from the following detailed description of the preferred embodiments having reference to the attached figures, the invention not being limited to any particular preferred embodiment(s) disclosed.
These and other features of the invention will now be described with reference to the drawings of a preferred embodiment, which are intended to illustrate and not to limit the invention, and in which:
The club head 10 also comprises an outer shell 20 that is preferably made of a strong yet lightweight composite material, such as, for example, a carbon fiber reinforced epoxy or carbon fiber reinforced polymer. As best seen in
With particular reference to
As mentioned above, the outer shell 20 preferably is attached to the strike/sole plate combination 34. To improve the strength of the connection between the outer shell 20 and the strike/sole plate combination 34, the outer shell 20 and the strike/sole plate combination 34 preferably include an interlocking joint 36, which is best seen in
As best seen in
To permanently secure the outer shell 20 to the strike/sole plate combination 34, an adhesive, such as, for example, an epoxy is applied to one or both of the mating sections 38a, 38b, preferably, along the attachment surfaces 41a, 41b. In a modified arrangement, the outer shell 20 can be secured to the strike/sole plate combination 34 by fasteners that can extend through the joint 36. As best seen in
To ensure a secure bond between the outer shell 20 and the strike/sole plate combination 34, the joint 36 (i.e., the interlocking step surfaces 38a, 38b) preferably are made with tight tolerances and smooth surfaces. More preferably, these components are made with a tolerance that is less than approximately ±0.15 millimeters. With respect to the interlocking step surface 38a of the outer shell 20, prior methods for producing carbon fiber club heads are not adequate for creating the desired tight tolerances and smooth surfaces. This is especially true with respect to the inner surface 21 of the outer shell 20 and the portion of which forms the interlocking step surface 38a of the outer shell 20 (see
For example,
One problem with the above-described method is that it is difficult to obtain tight tolerances and smooth surfaces on the interior surfaces 58 of the club head. This difficulty is due primarily to the nature of the inflatable bladder 52. As the bladder 52 expands, the composite material 50 is pressed against the hard smooth inner surface 55 of the mold 54. This tends to produce a smooth surface on the outer surfaces 60 of the composite material. In contrast, the relatively flexible surface of the inflatable bladder 52 presses against the interior surfaces 58 of the composite material. This tends to produce an uneven surface, which makes it difficult to obtain the tight tolerances and smooth surfaces.
A technique that is likely to be more successful in obtaining tight tolerance on the interior surfaces of the club head is shown in
This method, however, has a number of significant drawbacks. For example, because the resin must flow through the fibrous material, the fiber loading of the fibrous material must be kept to a relatively small amount. This reduces the strength of the final composite material. The method also requires the two halves 66, 68 of the mold 64 to be sealed so as to prevent the resin from leaking out of the mold 64. This increases the cost of manufacturing.
To address the above-noted problems, Applicant has invented a method for manufacturing a golf club having certain features and advantages. The method utilizes a mold 98, which is shown in
The mold 98 also comprises a first mold piece 112, which is shown in
The mold 98 further includes a second mold piece 120, which is shown in
As shown in
To form the outer shell 20 of the club head 10, an uncured composite material 150 is placed (i.e., laying up) around the core 100 (see
The second mold piece 130 then is moved towards the first mold piece 112.
Accordingly, the uncured composite material 150 is compressed between the first, second mold pieces 112, 120 and the core 100. As the second mold piece 120 is moved towards the first mold piece 112, the lower surface 152 (see
Preferably, while the composite material 150 is being compressed, the mold 98 is being heated in an oven to a temperature between 200-500 degrees Fahrenheit. More preferably, the mold 98 is heated to a temperature of approximately 350 degree Fahrenheit for approximately 10 minutes. The compressing and heating cures the composite material 150 into the desired shape, which is determined by the shape of the core 100 and the inner surfaces 114, 122 of the first and second mold pieces 112, 120.
After the composite material 150 is cured, the second and third mold pieces are removed. The core 100 can then be removed form the cured shell 20. The illustrated two piece construction of the core 100 aides the removal of the core 100. The finished shell 200 is removed from the mold 98 and attached to a corresponding strike/sole plate 34 combination with epoxy as described above.
In the illustrated arrangement, the strike/sole plate combination 34 is made of titanium or a titanium alloy. This arrangement is preferred because the material properties of titanium are particularly suited for the strike plate 12 and the sole plate 32. However, it should be appreciated that, in a modified arrangement, the above-described method can also be utilized for a club head wherein the strike plate 12 and/or the sole plate 32 are made of a composite material. In such an arrangement, a second mold (not shown) can be formed utilizing the principles described above. The second mold can be used to create a strike plate, a sole plate, or a strike/sole plate combination made of a composite material.
In another modified arrangement, the core 100 is attached to or integrally formed with the first mold piece 112. In such an arrangement, the uncured composite material 150 is placed over the core 100. The second mold piece 130 then is moved towards the first mold piece 112. After the composite material cures, the composite material 150 can be removed from the first mold piece 112.
Although this invention has been disclosed in the context of certain preferred embodiments and examples, it will be understood by those skilled in the art that the present invention extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses of the invention and obvious modifications and equivalents thereof. In addition, while a number of variations of the invention have been shown and described in detail, other modifications, which are within the scope of this invention, will be readily apparent to those of skill in the art based upon this disclosure. It is also contemplated that various combination or subcombinations of the specific features and aspects of the embodiments may be made and still fall within the scope of the invention. Accordingly, it should be understood that various features and aspects of the disclosed embodiments can be combine with or substituted for one another in order to form varying modes of the disclosed invention. Thus, it is intended that the scope of the present invention herein disclosed should not be limited by the particular disclosed embodiments described above, but should be determined only by a fair reading of the claims that follow.
Number | Date | Country | |
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Parent | 15877576 | Jan 2018 | US |
Child | 16288499 | US | |
Parent | 15404512 | Jan 2017 | US |
Child | 15877576 | US | |
Parent | 14048829 | Oct 2013 | US |
Child | 15404512 | US | |
Parent | 12730125 | Mar 2010 | US |
Child | 14048829 | US | |
Parent | 12253005 | Oct 2008 | US |
Child | 12730125 | US | |
Parent | 11401472 | Apr 2006 | US |
Child | 12253005 | US | |
Parent | 10941474 | Sep 2004 | US |
Child | 11401472 | US | |
Parent | 10621641 | Jul 2003 | US |
Child | 10941474 | US | |
Parent | 09878634 | Jun 2001 | US |
Child | 10621641 | US |