JPH08173580A - Golf club shaft - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a golf club shaft with a suitable amount of deflection and strength by forming the shaft by mutually connecting a plurality of cylindrical sections with tapered sections. SOLUTION: A golf club shaft 100 is formed of three parallel chambers (or sections) 101, 102, and 103 formed substantially in the shape of a right circular cylinder. The parallel sections 101 and 102 are connected together with a tapered section 104, and similarly, the sections 102 and 103 are connected together with a tapered section 105. In this case, the sections 101 to 105 are each manufactured of a carbon fiber composite material. In other words, pieces are formed of carbon fier prepreg material by specifically cutting it so that carbon fiber orientation may differ. For example, the carbon fiber prepreg material is cut in different biases to form each piece, and each of the sections 101 to 105 is shaped in combination according to each.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention is directed generally to golf club shafts, and specifically to golf club shafts made from carbon fiber composite materials that are uniquely incorporated.

[0002]

2. Description of the Related Art In recent years, equipment used in golf games has been remarkably developed. For example, so-called "wood" clubs now include clubs called "metal wood". The shafts of these clubs are
It has been developed into new kinds of materials such as rolled steel, aluminum, graphite and titanium. The shaft is also manufactured from carbon fiber type materials.

All shafts are designed to provide substantial strength to prevent the shaft from breaking. Further, the shaft is designed to provide varying amounts of deflection and / or stiffness. Golf club shafts are designed to provide different types of energy storage and release during backswings and forwardswings to provide more energy when hitting a golf ball.

To the extent possible, manufacturers continue to experiment and develop new golf club shafts by introducing new types of materials and new types of incorporation. The best golf club shaft is always pursued.

[0005]

SUMMARY OF THE INVENTION The present invention is directed to golf club shafts made from composite materials such as carbon prepreg. The shaft incorporates three cylindrical (or parallel) sections joined together by a pair of tapered sections. By using the appropriate material, the shaft can achieve the appropriate amount of deflection and strength.

The shaft has a unique method of providing the composite material, incorporating the composite material, and finishing the shaft.
Be incorporated.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIG. 1, there is shown a perspective view of a golf club shaft made in accordance with the present invention. In this figure, a golf club shaft 100 has three parallel chambers 101, 102 and 1
Including 03. These chambers or sections are shown parallel because they are actually right cylinders.

The parallel sections 101 and 102 are joined by a tapered section 104. Similarly,
The parallel sections 102 and 103 are joined together by a tapered section 105. As shown in FIG. 1, tapered sections 104 and 105 are fairly large.

The same general construction is equally applicable to golf club shafts for so-called wood clubs and iron clubs. The most important difference in construction of wood or iron club shafts is the overall length dimension. For example, shafts used in wood clubs are typically on the order of 45 inches in length, while shafts for iron clubs are on the order of 39 inches in length. The shaft diameter at the thick end is about 0.60 inches (wood) and 0.615 inches (iron), while the tip diameter is about 0.335 inches (wood).
And 0.370 inch (iron).

Referring now to Table 1, there is shown a list of approximate dimensions (in mm) for each section of wood club shafts and iron club shafts.

[0011]

[Table 1]

Referring now to FIG. 2, a plurality of components are shown, which are flat sheets of suitable carbon fiber material. As noted, one of the suitable types of materials for the preferred embodiment of this invention is the 5218 prepreg manufactured by Cytec Structural Materials, Inc. of Anaheim, California. Called system. This material can be obtained in rolls or sheets and cut into the preferred shape as shown in FIG.

The prepreg material comprises carbon fibers and resin arranged in a particular orientation. By cutting the sheet appropriately, pieces of material with different carbon fiber orientations can be provided.

For example, as shown in FIG. 2, pieces 210 and 220 are planar sections of prepreg material. Pieces 210 and 220 are essentially mirror images of each other. These pieces are cut with different biases in the prepreg material. For example, piece 210 is +
Cut on a 45 ° line, while piece 220 is -45 °
Is cut on the line. Therefore, pieces 210 and 220 consist of elements that are placed with a relative bias of 90 ° overall.

In this embodiment, pieces 210 and 220, called bias layers, have thick ends and tips that are the same size as each other.

Further, each of the pieces 210 and 220 is cut to remove some of its triangular portions 211 and 212, which are parallel sections 101, 102 and 103 and tapered section 104 shown in FIG. And 105 are designed to help create.

The other elongated components 250 and 260 are the same length as the pieces 210 and 220, in this case about 1010 mm. The tip of the piece 250 is slightly wider than the tips of the pieces 210 and 220. The tip of the piece 260 is slightly wider than the tip of the piece 250. The thick ends of the piece 260 are the pieces 210 and 220.
The width of the piece 250 is slightly wider than the wide end of the piece 250.

Pieces 250 and 260, called layers 1 and 2, are both cut in the prepreg material with a 0 ° bias. That is, the carbon fiber orientation in each piece is parallel to the long axis of the piece.

The reinforcing layers 230 and 240 are also cut with a 0 ° bias. The reinforcement layer 230 is, of course, a right triangle piece, while the shape of the reinforcement piece 240 is a right trapezoid.

The prepreg material typically has a thickness of about 0.
It is also noted that it is 15 mm. Further, the materials can be formed with different tensile strengths or tensile moduli. Typically, pieces 210 and 220 are
Formed from so-called 30 ton or high modulus carbon fiber (defined by the manufacturer) containing 31% resin. Conversely, layers 1 and 2 are made from a medium modulus carbon fiber material with 34% resin. The reinforcing layer is made from a medium modulus carbon fiber material with 36% resin.

The particular dimensions and modulus of the pieces shown and described are not absolute. Modifications thereto can be incorporated into the present invention. Those changes are merely directed to the flexure and / or strength of the shaft.

Referring now to FIG. 3, the preliminary steps in the assembly of the shaft are shown. Specifically, the reinforcing layer 240 is placed or affixed to the surface of the piece 220. In the preferred arrangement, the right-angled corner of the right-angled trapezoidal reinforcing layer 240 is placed at the right-angled corner of the tip of the bias layer 220. Typically, these layers are simply placed against each other. That is, the layers tend to adhere well to each other due to the tackiness of the material so that subsequent work may be performed.

Referring now to FIG. 4, another step in the preparation of the shaft is shown. In this case, the bias layer 220 with the reinforcement layer 240 on top of it is the bias layer 21.
It is covered with 0 and triangular reinforcing layers 230. Specifically, the bias layer 210 is aligned with the enhancement layer 240 at its edges. However, the lower straight edge of the bias layer 210 is offset from, but aligned with, the lower straight edge of the reinforcing layer 240. The offset between the two bias layers is generally equal to the diameter of the mandrel 401 on which the rolling operation is performed.

After the bias layer 210 is placed on top of the bias layer 220 with the reinforcement layer 240 in place, a triangular reinforcement piece 230 is placed thereon. The right-angled corners of the triangular reinforcing layer 230 provide bias layers 210 and 22.
Aligned with the right angle created by the zero tip as well as the lower edge of the bias layer 210 located above the bias layer 220.

Referring now to FIG. 5, there is shown a schematic or functional flow chart of a manufacturing process for manufacturing the improved golf club shaft of the present invention.

In the flow chart, a stage or step is defined as the time when work is performed on individual pieces of composite material. Therefore, the pieces cut during step 501 are the layers 210, 22 shown in FIG.
0, 230, 240, 250 and 260. In step 502, the layers are then assembled and placed on the mandrel 401 as shown in FIGS. In step 503, the incorporated layers are then placed on a conventional rolling machine with mandrel 401, which is adapted to wrap a layer of prepreg material around mandrel 401. The mandrel is slightly tapered as desired by the shaft manufacturer.

In this case, the reinforcement layer 240 is wrapped around the tip of the shaft, and the triangular reinforcement layer 230 is also wrapped. These components add strength and rigidity to the tip of the shaft, with the removed portions shown in pieces 210 and 220, along with the parallel portion 10 of shaft 100.
Establish 1, 102 and 103 (see FIG. 1).

In step 504, a second rolling operation is performed on a conventional rolling machine. In this step, the first 0 ° layer comprising layer 250 is
A rolled layer 210 created during the first rolling operation,
It is wrapped around 220, 230 and 240 and the mandrel.

In step 505, a third rolling operation is performed and the layer 260 is removed from the second layer of step 504.
Wrapped around the equipment manufactured during the rolling process.

In step 506, the third roll manufactured unit is wrapped with a suitable wrapper such as, but not limited to, cellophane. The wrapper is wrapped fairly tightly and snugly around the assembly produced in step 505. This wrap layer maintains the other prepreg layers in the desired shape.

In step 507, the device is heat treated. Specifically, the entire fixture is placed in the oven and
Heat to 0 ° F for about 2 hours. Thus, the wrap layer maintains the shape of the device. After the heat treatment is complete and the assembly is cooled to room temperature, in step 508, step 5
The wrap given at 06 is removed.

In step 509, the shaft is then subjected to a grinding operation to completely smooth the surface of the assembly.

At step 510, the outer surface of the assembly is painted in a conventional manner. Many suitable paint applicators are known in the art. The type of paint used is also conventional.

In step 511, the assembly is subjected to a precision grinding procedure to smooth any imperfections that may have occurred during the painting step.

In step 512, the assembly
It can be subjected to an appropriate process to give a logo or other indicia to the surface of the assembly. Typically this process may be performed in a silk screening operation.

In step 513, the finished assembly is provided with a transparent coating, such as lacquer, paint, etc., to provide a glossy or dull top finish, as desired.

The shaft is now fully completed and ready to be incorporated into the grip and head to complete the manufacture of the golf club. The shaft is not limited to any particular shape of wood or iron except as noted above for its dimensions.

Although the process shown in FIG. 5 is exemplary, it is understood that modifications thereto can be made without departing from the scope of the invention. For example, in some cases, especially in the manufacture of shafts for iron clubs, the third rolling step, step 505, may be omitted.

Similarly, in step 506, a material other than cellophane can optionally be used to wind the shaft.

The temperature and time profiles described with respect to step 507 can be modified as desired or depending on the material used to form the shaft.

In some cases, steps 508 and 5
09 can be combined and the grinding operation can remove the wrapper.

Although unlikely, the painting step 510 can be omitted to leave the shaft in its natural state.

A precise grinding step (step 511),
Step of giving a logo or similar indication (step 51
The completion step consisting of 2), and the step of providing a transparent coating (step 513) can be omitted or modified.

As explained above, when the process shown in FIG. 5 is completed, the shaft 100 shown in FIG. 1 is manufactured. This shaft has a high standard strength modulus and is flexible enough for most golfers to have the two energy kick points shown in Figure 1, where the golfer allows the shaft to be used during the backswing. The energy stored in the is released during the downswing.

Thus, the unique design and concept of a golf club shaft and method of making it has been shown and described. Although this description is directed to particular embodiments, it is understood that those skilled in the art may envision variations and / or modifications to the particular embodiments shown and described herein. Any such variations or modifications that are within the scope of this description are intended to be included therein as well. It is understood that the description herein is intended to be illustrative only and not limiting. On the contrary, the scope of the invention described herein is limited only by the appended claims.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a preferred embodiment of a golf club shaft made in accordance with the present invention.

FIG. 2 is an illustration of component pieces assembled to form a golf club shaft of the present invention.

FIG. 3 is a plan view of a partial assembly of the golf club shaft of the present invention.

FIG. 4 is a plan view of another partial assembly of the golf club shaft of the present invention.

FIG. 5 is a block diagram of a flowchart of a process for assembling the golf club shaft of the present invention.

[Explanation of symbols]

 100 Golf Club Shaft 101 Parallel Section 102 Parallel Section 103 Parallel Section 104 Tapered Section 105 Tapered Section

Claims (14)

[Claims] 1. At least three cylindrical sections and at least two tapered sections, each of said tapered sections being integrally disposed between two of said cylindrical sections and having one A golf club shaft that forms an elongated shaft. 2. The golf club shaft of claim 1, wherein each section is made of carbon fiber composite material. 3. The golf club shaft of claim 1, wherein each of the cylindrical sections has a different outer diameter. 4. The golf club shaft of claim 1, wherein the cylindrical section and the tapered section are joined together. 5. The golf club shaft of claim 4, wherein the cylindrical section of the shaft comprises about 55% of the total length of the shaft. 6. A golf club shaft comprising: a plurality of cylindrical sections having different diameters; a tapered section disposed between and adjacent to adjacent cylindrical sections to provide two kick points for the shaft. A golf club shaft, including a section. 7. Incorporating a plurality of pre-cut planar layers of prepreg carbon fiber composite material along a preferred carbon fiber orientation, and winding said layers on a tapered mandrel, thereby providing a shaft cylinder. And a golf club shaft formed by a method in which a tapered portion is manufactured. 8. Including heat treating the shaft,
The golf club shaft according to claim 7. 9. The golf club shaft of claim 7, including smoothing the surface of the shaft. 10. The golf club shaft of claim 7, including finishing the shaft by applying a suitable coating to its surface. 11. The golf club shaft of claim 10, wherein the coating comprises a layer of paint. 12. At least two of said layers are 9 to each other.
A bias orientation of the carbon fibers arranged at 0 °,
The golf club shaft according to claim 7. 13. The golf club shaft of claim 12, wherein at least one of the layers has a 0 ° bias orientation intermediate between the two bias orientations of the layers. 14. At least one of the layers is a reinforcing layer that is a 0 ° bias of the carbon fibers.
The golf club shaft described in.