JP3179247B2 - Method of manufacturing sports related parts - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a golf club shaft and head, as well as such a tennis racket, a method of manufacturing a sports member using the resin material.

[0002]

2. Description of the Related Art In recent years, the application of carbon fiber reinforced resin (CFRP) to sports applications has been remarkable with the progress of technological development. Particularly, in golf shafts and tennis rackets, the specific strength and specific stiffness of carbon fiber are large. The development of lightweight and high-quality products has been promoted by using the stencil. Recently, it has also been applied to golf heads due to rule revision. However, delicate weight adjustment and the position of the center of gravity are important factors for extending the flight distance and obtaining swing stability in the golf head.

In the prior art, a small piece of lead, which is a metal having a relatively high specific gravity, was formed together with a CFRP material in order to adjust the weight of a golf head. However, in this method, the lead does not deform along the mold during molding, so that the position and size of the lead to be inserted into the head are limited, so that not only a golf head having the target performance but also a target performance cannot be obtained. The degree of freedom was also very limited. Further CF
Due to the difference in the expansion coefficient between the RP material and the lead and the poor adhesiveness, the interface tends to peel off after molding, causing abnormal noise during the swing of the golf club.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to solve such a conventional problem and to provide a resin molding material having a high specific gravity which is suitable as a weight adjusting material for sports-related members, particularly golf heads. .

[0005]

The present invention adopts the following constitution in order to solve the above-mentioned problems. That is, the present invention
Metal fine particles having a specific gravity of 11 or more in the base material are resin / fine particles =
8: 2 to 4: 6 (volume ratio) mixed resin molding material
Of sports-related parts for attaching weight for weight adjustment
Is the way .

In the present invention, carbon fibers,
Graphite fiber, boron fiber, aramid fiber, glass fiber, metal fiber, etc., consisting of reinforcing fibers used for ordinary fiber-reinforced composite materials, nylon fibers or polyester fibers,
Those having a shape such as a tow, a felt, a cloth, a web, and a nonwoven fabric are suitably used.

The thermosetting resin suitable for the present invention may be any of epoxy resin, unsaturated polyester resin, vinyl ester resin, phenol resin and the like.
A rheometer viscosity at 10 ° C. of 10 to 10 ⁴ poise is preferred. If it is less than 10 poise, the separation and flowability of the fine particles and the resin become large, which is not preferable. If it exceeds 10 ⁴ poise, it becomes difficult to mix the fine particles into the resin, which is also not preferable.

The metal fine particles having a specific gravity of 11 or more in the present invention are not particularly limited, and lead and tungsten fine particles can be used. Tungsten fine particles having a large specific gravity and having no toxicity are preferably used. If the specific gravity of the metal fine particles is less than 11, the specific gravity of the composition decreases, and new problems such as the inability to achieve the desired performance and the use of a large amount of the composition cause a change in the shape of the head. The addition amount of the metal fine particles is as follows: resin / fine particles = 8: 2
The ratio of 4: 6 is preferable. If the ratio is less than 4: 6, the specific gravity of the composition decreases, and the fine particles easily flow during molding, so that the target performance cannot be exhibited. In addition, if it exceeds this, problems arise in handleability and uniformity, which is also undesirable.

Further, the particle size of the metal fine particles to be used is 0.1.
It is preferably from 5 to 16 µ, more preferably from 1 to 8 µ. If the particle size is less than 0.5 μm, the powder may fly in the air at the time of weighing or resin preparation, leading to deterioration in workability and environment, and
If it exceeds 6 μm, the resin is not densely filled, and thus problems such as non-uniformity and irregularity in molding are caused. The method for producing a resin molding material containing metal fine particles is not particularly limited, but a method of bonding a resin composition formed in a film shape or a method of directly coating a substrate is preferably used. Hereinafter, the present invention will be described specifically with reference to examples.

[0010]

EXAMPLE A resin obtained by adding 0.6 part of dicumyl peroxide as a curing agent to 100 parts of a vinyl ester resin was added to 85 parts of the resin.
Wt% tungsten particles (specific gravity 19.4, particle size 4 ~
7.99Myu, Japan New Metals Co., Ltd.) was added, sufficient After stirring prepared, and the film-like basis weight 1500 g / m ² using a doctor knife method, tension molding material as a substrate a glass cloth having a basis weight of 15 g / m ² on one side I got

Next, SM made of a vinyl ester resin containing 40% by weight of carbon fibers cut to a length of 25 mm.
When molding the head in C, the above-mentioned metal particle-containing molding material was included in a predetermined position for weight adjustment, and was molded by a compression molding method. When the wood club having the head thus formed was hit 1000 times, no abnormal noise or the like was generated.

For comparison, when molding a head with an SMC made of a vinyl ester resin containing 40% by weight of carbon fibers cut to a length of 25 mm, a lump of lead was included in a predetermined position for weight adjustment and compression molding was performed. Molding. When the wood club having the head thus formed was hit 1000 times, a slight noise was generated.

[0013]

According to the resin molding material of the present invention having the above-described structure, the fine metal particles are uniformly dispersed in the resin, and no separation occurs between the metal particles and the resin. When used as, it is possible to perform an optimal swing without abnormal noise when hitting a ball.

Claims (2)

(57) [Claims] 1. A base material comprising metal fine particles having a specific gravity of 11 or more,
Resin / fine particles = 8: 2 to 4: 6 (volume ratio) mixed
Sports to attach resin molding material to adjust weight
Manufacturing method of related members. 2. The method according to claim 1, wherein the metal particles have a particle size of 0.5 to 16 μm.