JPH02189169A - Shaft for golf club - Google Patents

Abstract

PURPOSE:To reduce an influence exercised on a flying distance due to the difference in a swing of a golfer occasioned by a temperature change by a superresilient alloy the modulus of elasticity of which is changed due to a temperature change is composited with a shaft made of FRP, and the bending characteristics of a shaft are changed according to a temperature change. CONSTITUTION:A shaft for golf club made of FRP is formed such that an FRP layer 1 having an orientation angle of a reinforcing fiber with a longitudinal being + or -25 deg. or more and an FRP layer 3 having the orientation angle of + or -25 deg. or less are superposed with each other. In this shaft, a fiber formed of a superresilient alloy or a ribbonform foil is wound around the whole length or a part of the length of a shaft at an orientation angle of 25 deg. or less to form a superresilient alloy layer 2. The superresilient alloy has a transformation temperature set to a value between -5-+30 deg.C. As a result, since the shaft has temperature dependency in which a modulus of elasticity is reduced in the case of reduction of an atmospheric temperature, a gold club for which the shaft is used is apt to bend during a winter season. Thus, a flying distance of gold ball is not differed with that during a summer season, and the feeling of a shaft made of a metal can be held.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement of a shaft for a golf club made of FRP.

[Conventional technology]

Currently, shafts for golf clubs (hereinafter referred to as shafts)
There are metal shafts made of rope, various alloy nets, and light alloy nets, and so-called FRP shafts made of synthetic resins reinforced with various fibers such as carbon fiber.

[Invention tries to solve! ll! [Question] As mentioned above, there are two types of shafts: metal shafts and FRP shafts.
In recent years, FRP shafts have been growing significantly. this is,
Although FRP shafts have the advantage of being lighter and more flexible than metal shafts, they initially had the disadvantage of being weak to twisting and easily breaking, so they were not widely used. However, when manufacturing using a filament winding method or the like, a layer with reinforced torsion in which the reinforcing fibers are oriented at an angle of ±25° or more with respect to the longitudinal axis direction, and a layer with strengthened twist in which the orientation angle of the reinforcing fibers is made less than ±25° This is because the above-mentioned drawbacks were solved by polymerizing.

By the way, in general, the temperature changes in the morning and during the day, and throughout the seasons. For example, the temperature is different in summer and winter, so when a golfer swings, his body becomes stiffer in winter, and his swing is different from that in summer. Become. On the other hand, for FRP shafts and metal shafts, the bending characteristics of the shafts do not change due to the above temperature changes, so the difference in golfers' swings causes changes in head speed, and in winter, the head speed decreases and the golf ball The disadvantage is that the flight distance is reduced. In addition, although FRP shafts are generally well received, some golfers who have been using metal shafts for many years and are accustomed to them avoid using FRP shafts because of the difference in the feel of the swing. There are many.

To improve this point, attempts have already been made to combine FRP shafts with metal fibers such as boron, titanium, SUS, etc., but even in this case, there is no temperature dependence of the shaft, that is, the bending characteristics of the shaft. is the same in winter and summer, for example, and therefore the difference in the golfer's swing depending on the temperature results in a difference in the flight distance of the golf ball, and the above-mentioned drawback cannot be eliminated.

The present invention was developed in view of the above problems, and it combines a superelastic alloy whose modulus of elasticity changes with temperature changes, changes the bending characteristics of the shaft depending on the temperature, and improves the flexibility of golfers.
FR that has the feel of a metal shaft and has little effect on flight distance due to swing differences due to temperature changes.
The purpose of this invention is to provide a shaft mainly composed of P.

[Means to solve the problem]

The golf club shaft according to the present invention is a golf club shaft made of FRP in which an FRP layer in which reinforcing fibers have an orientation angle of ±25° or more with respect to the longitudinal direction is superposed, and an FRP layer in which the orientation angle of reinforcing fibers is less than ±25°. A superelastic alloy layer is formed by wrapping fibers or ribbon-like foil made of an elastic alloy over the entire length or part of the shaft at an orientation angle of 25° or less.

Although there is no particular restriction on the order of polymerization of the superelastic alloy layer and the FRP layer in the present invention, it is preferable to provide the superelastic alloy layer between the two FRP layers in order to reduce the manufacturing process.

Furthermore, considering the temperature difference between summer and winter, the metamorphosis temperature should be set at -5℃~+
It is preferable to use a superelastic alloy set within the range of 30° C., that is, a superelastic alloy whose elastic modulus rapidly increases from the low temperature side to the high temperature side near the above transformation temperature.

(Function) When using a golf club using the shaft according to the present invention, the golfer's body becomes stiff during low temperatures such as in winter, and the head speed of the golf club decreases, but on the other hand, the elastic modulus of the superelastic alloy The shaft becomes softer due to the lowering of the shaft, making it more likely to bend, but the flight distance of the golf ball does not decrease.

Also, when the temperature rises in the summer, the shaft becomes stiff,
Golfers' bodies have become softer, so the distance they hit is not much different than in the winter.

Furthermore, since the FRP shaft is composited with metal, it has a good feel.

〔Example〕

Hereinafter, the present invention will be explained in detail based on the drawings.

FIG. 1 is a partial cross-sectional perspective view of the shaft, in which 1 is an F and RP layer, 2 is a superelastic alloy layer, and 3 is an FRP layer, which are formed as follows.

That is, trading card T300 (carbon fiber, product name manufactured by Toshi Co., Ltd.) is made by filament winding on a tapered core metal with an inner diameter of 4 to 13φ and a total length of 1200 m.
Impregnated with epoxy resin, orientation angle ±45 @ thickness 0.7
Wind it until it becomes 5u (1) 0th, diameter 100μ,
Superelastic alloy fiber (manufactured by Furukawa Electric Co., Ltd.) set at a transformation temperature of 10°C was wound 50 times (100 fibers) at ±10° (2);
Further, the above carbon fiber is wound at ±10° to a thickness of 2.0 m (3).

Next, this is placed in an autoclave, and after the resin has hardened, the core metal is pulled out, and the surface is polished and painted to form a golf shaft.

FIG. 2 is a graph showing the temperature dependence of the shaft of the present invention, that is, the relationship between the bending rigidity of the shaft and temperature.

Next, Table 1 shows the results of comparing the characteristics of golf clubs using the shaft of the above embodiment, the conventional FRP shaft using carbon fiber, and the metal shaft using steel.

From the above results in Table 1, it is clear that the golf club using the shaft of the present invention is superior to the golf club using the conventional shaft in terms of flight distance and feel of the golf ball due to temperature changes. .

[Effects of the Invention] As mentioned above, since the shaft of the present invention is mainly composed of FRP and is composed of a superelastic alloy, there is a temperature dependence in that the elastic modulus decreases when the temperature decreases. Therefore, golf clubs using the above-mentioned shafts become more flexible in the winter, so the flight distance of the golf ball is the same as in the summer, and the feeling of a metal shaft can be maintained, so it is better than the conventional one. The drawbacks of FRP golf clubs can be improved, and the effect is extremely large.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional perspective view showing an embodiment of a golf club shaft according to the present invention, and FIG. 2 is a graph showing the relationship between bending rigidity and temperature of the golf club shaft. Explanation of symbols l... - FRP layer 2 - Superelastic alloy layer procedure (Hoshosho (self-proposal) July 26, 1999 1, Display of the case 1999 Patent layer No. 7953 2, Name of the invention Golf Club shaft 3, name of the person making the amendment, name of relationship to the case 4, agent's postal code and residence

Claims (1)

[Claims] 1. A shaft for a golf club made of FRP, which is formed by superposing an FRP layer in which reinforcing fibers have an orientation angle of ±25° or more with respect to the longitudinal direction and an FRP layer in which the orientation angle is less than ±25°. A shaft for a golf club, characterized in that a superelastic alloy layer is formed by wrapping fibers or ribbon-like foil made of a superelastic alloy over the entire length or part of the shaft at an orientation angle of 25° or less. 2. The shaft for a golf club according to claim 1, wherein the superelastic alloy layer is formed between both FRP layers. 3. The shaft for a golf club according to claim 1 or 2, wherein the superelastic alloy has a transformation temperature set between -5°C and +30°C.