JPH0717329Y2 - Golf club - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a golf club, and more particularly to a golf club having an improved structure of a connecting portion between a head and a shaft.

[Prior Art] FIG. 4 shows a conventional golf club, in which reference numeral 11 denotes a head having a neck portion 13.

A shaft hole 15 is formed in the neck portion 13, and a tip end portion of a shaft body 17 formed by laminating high-strength fibers is inserted into the shaft hole 15 and fixed by an adhesive 19.

In this example, the hole 23 formed in the shaft body 17
A balancer 27 fixed by a plug 25 is arranged at the tip of the.

A socket 29 for fixing the shaft body 17 is arranged at the end of the neck portion 13.

In recent years, in such golf clubs, a material having a larger elastic coefficient has been used for high-strength fibers such as carbon fibers forming the shaft body 17,
Is being made thinner and thinner.

[Problems to be solved by the device]

However, in this way, when using a high-strength fiber having a larger elastic coefficient to make the shaft body 17 thinner and thinner, when an impact load acts on the head 11,
Stress concentration occurs at the joint between the head 11 and the shaft body 17,
There is a problem that the shaft body 17 may be damaged.

Therefore, conventionally, the joint between the head 11 and the shaft body 17 is protected by another member, or the wall thickness of the joint of the shaft body 17 is increased, but in this case,
There is a problem that the weight of the golf club increases.

The present inventor has found the following as a result of diligent research aimed at solving such conventional problems.

That is, conventionally, the outer periphery of the shaft body 17 is polished to insert the shaft body 17 into the shaft hole 15 of the head 11, but if such polishing is performed, the shaft body 17
It was found that the high-strength fiber of (3) is cut and the shaft body 17 is strongly affected by stress concentration and is easily damaged.

Moreover, in such a golf club, although stress concentrates on a head fitting end, it was found that the higher the rigidity of this part, the more stress concentrates and the more likely it is to break.

The present invention has been made based on such findings, and an object of the present invention is to provide a golf club capable of significantly reducing stress concentration on the shaft body as compared with conventional golf clubs.

[Means for Solving the Problems]

The golf club of the present invention is a golf club in which a tip portion of a shaft body formed by laminating high-strength fibers is inserted into a shaft hole formed in a neck portion of a head. In addition to forming a build-up layer having a lower rigidity in the axial length direction than the shaft body, the insertion portion of the build-up layer into the shaft hole is ground without polishing the shaft body, It is inserted into the hole.

[Action]

In the golf club of the present invention, a built-up layer having a lower rigidity in the axial direction than that of the shaft body is formed at and near the tip of the shaft body, and the insertion portion of the built-up layer into the shaft hole is formed in the shaft body. Since the high-strength fiber of the shaft main body is not cut or damaged by polishing, since the polishing is performed without polishing and the polishing portion is inserted into the shaft hole.

Further, since the buildup layer located at the head fitting end is formed so as to have a lower rigidity in the axial direction than the shaft main body, stress concentration acting on this portion is relaxed.

〔Example〕

Hereinafter, the details of the present invention will be described with reference to the embodiments shown in the drawings.

FIG. 1 shows details of the tip portion of the shaft shown in FIG. 2 and its vicinity, and FIG. 2 shows an embodiment of the golf club of the present invention.

In FIG. 2, reference numeral 31 indicates a head having a neck portion 33.

A shaft hole 35 is formed in the neck portion 33, and the tip end portion of the shaft main body 37 is inserted into the shaft hole 35 and fixed by an adhesive 39.

The shaft body 37 is made of synthetic resin (eg, epoxy).
Is formed by laminating high-strength fibers (for example, carbon fibers) to be impregnated.

In this embodiment, the balancer 45 fixed by the plug 43 is provided at the tip of the hole 41 formed in the shaft body 37.
Are arranged.

A socket 47 for fixing the shaft body 37 is arranged at the end of the neck portion 33.

Therefore, in this embodiment, as shown in FIG.
A built-up layer 49 having a lower rigidity in the axial direction than 37, that is, a small elastic coefficient is formed.

The built-up layer 49 includes high-strength fibers 51 (for example, an epoxy resin) impregnated with a synthetic resin (for example, epoxy) on the outer periphery of the shaft body 37.
It is formed by laminating carbon fiber and glass fiber).

The insert portion of the overlay layer 49 into the shaft hole 35 and the socket 47 is polished without polishing the shaft body 37, and the polished portion 53 includes the shaft hole 35 and the socket portion 47.
Has been inserted into.

Then, in the golf club configured as described above,
At the tip of the shaft main body 37 and in the vicinity thereof, a built-up layer 49 having a small rigidity in the axial direction is formed by the shaft main body 37, and an insertion portion of the built-up layer 49 into the shaft hole 35 is provided.
Polish the shaft body 37 without polishing,
Since 53 is fitted into the shaft hole 35, the high-strength fiber 51 of the shaft body 37 is not cut or damaged by polishing.

Therefore, the stress concentration on the shaft body 37 is relieved, and the damage to the shaft body 37 can be significantly reduced as compared with the conventional case.

Further, since the built-up layers 49 located at the head fitting end portions 55 and 57 are formed so as to have lower rigidity in the axial length direction than the shaft body 37, stress concentration acting on this portion can be made larger than in the conventional case. Therefore, the damage to the shaft can be significantly reduced as compared with the conventional one.

Further, in the golf club configured as described above, since the built-up layer 49 having lower rigidity than the shaft main body 37 is polished, the dimensional accuracy by polishing is improved, and the head 31 is fitted into the shaft hole 35. The accuracy can be improved and polishing can be performed relatively easily.

Further, in this embodiment, the high-strength fiber 51 is connected to the shaft main
Since it is wound around the outer periphery of the shaft, the rigidity in the axial direction can be easily reduced.

FIG. 3 shows another embodiment of the golf club of the present invention. In this embodiment, a split preventing filament 59 is spirally wound around the outer circumference of the shaft body 37. An outer coating layer 61 is formed on the outer layer, and a buildup layer 63 is formed on the outer side of the outer coating layer 61.

In this embodiment, the fragmentation preventing filaments 59 are made of a material having poor adhesion to the tubular body main body 11 such as polyethylene fibers (for example, TECMILON), polypropylene fibers, etc. Alternatively, a yarn body in which a fiber bundle is bundled by a sizing material or twisted to be bundled is used.

In the golf club configured as described above, substantially the same effect as that of the embodiment shown in FIG. 1 can be obtained. However, in this embodiment, since the division preventing filaments 59 are arranged, the shaft main body 37 is Even if the head is divided, since the tip end portion is connected by the division preventing filamentous material 59, it is possible to reliably eliminate the risk of the head 31 flying and hitting a person.

In addition, in the above-mentioned embodiment, the example in which the built-up layer 49 is formed of the high-strength fiber is described, but the present invention is not limited to such an embodiment, and may be formed by, for example, coating or the like. Of course good things.

[Effect of device]

As described above, according to the present invention, a built-up layer having a lower rigidity in the axial direction than that of the shaft body is formed at the tip of the shaft body and in the vicinity thereof, and the insertion portion of the built-up layer into the shaft hole is formed. Since the shaft main body is polished without polishing and the polishing portion is fitted into the shaft hole, there is an advantage that stress concentration on the shaft main body can be significantly reduced as compared with the conventional case.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing details of the tip portion of the shaft of FIG. 2 and its vicinity. FIG. 2 is a partial longitudinal sectional view showing an embodiment of the golf club of the present invention. FIG. 3 is a longitudinal sectional view showing another embodiment of the golf club of the present invention. FIG. 4 is a partial vertical sectional view showing an example of a conventional golf club. [Explanation of symbols for main parts] 31 …… Head 33 …… Neck part 35 …… Shaft hole 37 …… Shaft body 49 …… Overlaying layer 53 …… Abrasion part

Claims (1)

[Scope of utility model registration request] 1. A golf club having a shaft body formed by laminating high-strength fibers, which is inserted into a shaft hole formed in a neck portion of a head. While forming a build-up layer having a lower rigidity in the axial length direction than the shaft body, the insert portion of the build-up layer into the shaft hole is ground without polishing the shaft body, and the polished part is formed in the shaft hole. A golf club characterized by being inserted.