JPH0576469U - Golf club shaft - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a shaft for a golf club, which is made of fiber reinforced plastic having high strength at the tip portion of the shaft and excellent in feeling. [Structure] An outer layer 3 of a fiber-reinforced plastic shaft 1 having an inner layer 2 and an outer layer 3, or an inner layer 2, a middle layer and an outer layer 3.
As for the orientation angle of the fiber in, the range from the small diameter end to 200 mm is 0 ° to ± 20 °, the range from 200 mm to 400 mm is ± 15 ° to ± 30 °, and 200 m from the small diameter end.
m is approximately the same thickness, and 200 mm to 400 mm is thinner than the portion 200 mm from the small diameter end.
The bending rigidity ratio of 00 mm to 400 mm and 200 mm from the small diameter end is set to 1: 1 to 2. A filament winding method was used for shaft molding.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a golf club shaft made of fiber reinforced plastic.

[0002]

[Prior Art]

 Currently, there are golf club shafts (hereinafter referred to as shafts) made of metal and fiber reinforced plastic (hereinafter referred to as FRP), but they are made of FRP because of their light weight, high rigidity, and freedom of design. Shaft is stretched.

On the other hand, a club head (hereinafter referred to as a head) mounted on this shaft is made of wood such as a persimmon tree, metal, FRP or the like for wood, and is a composite of metal and FRP for iron. However, when the head material is made of metal, the stress generated in the neck part when hit is different from that of heads made of other materials due to the difference in the shape and rigidity of the neck part due to the material. growing. For this reason, the bending and impact strength in the vicinity of the neck portion of the shaft on which the metal head is mounted must be higher than in the case of heads made of other materials.

However, in a FRP shaft, if the weight is reduced, the twist is reduced, and the flexion (torque) is reduced, the strength of the shaft alone may cause the strength in the vicinity of the neck portion due to the structure of the base material and the wall thickness. Even if the head is made of wood or FRP, it may be sufficient, but particularly in the case of a metal head, there is a high possibility that it may be broken, which may be a problem in practical use.

Therefore, conventionally, as a countermeasure against the above, in view of the constitution of the base material, a carbon fiber having higher strength is used, or a fiber having higher elongation such as glass fiber is compounded to secure bending and impact strength. The method of doing is adopted.

Further, in terms of shape, a method is adopted in which the tip diameter of the cored bar used at the time of molding the shaft is made small, that is, the wall thickness of the tip part of the shaft is made thick to secure the strength.

[0007]

[Problems to be solved by the device]

 Among the methods described in the prior art, the former method of securing the bending and impact strength of the base material may cause problems in terms of price, weight, and other characteristics, and in particular, the small diameter of the shaft. As for the bending rigidity of the tip end on the side, as shown by the broken line I in FIG. 2, the ratio of 200 mm from the tip on the small diameter side (hereinafter referred to as the tip) and 200 mm to 400 mm is 1/1 to 2/1, If the bending rigidity is from 200 mm to 200 mm, the 200 mm to 400 mm part will inevitably become higher, that is, the tip part will be hard and strength will be secured, but the tip of the shaft ( There was a problem that the feeling was poor and the feeling was poor.

Further, the latter method of increasing the wall thickness of the tip portion of the shaft also has a problem in terms of feeling as in the above case.

The present invention has been made in view of the above problems of the prior art. The object of the present invention is to secure the strength in the vicinity of the neck portion of the shaft and to improve the feeling. The present invention is intended to provide a golf club shaft made of FRP, which is excellent.

[0010]

[Means for Solving the Problems]

 In order to achieve the above object, a golf club shaft according to the present invention is a tapered tubular shaft made of fiber reinforced plastic, and the golf club shaft has an inner layer and an outer layer having different orientation angles with respect to the axial direction of the fiber. In the above, the orientation angle of the fibers in the outer layer is 0 ° to ± 20 ° in the range from the small diameter end to 200 mm, ± 15 ° to ± 30 ° in the range from 200 mm to 400 mm, and the above 200 mm to 400 mm. The bending rigidity ratio of 200 mm from the small diameter end is 1: 1 to 2.

Further, the head mounted on the tip of the shaft on the small diameter side may be made of any material such as wood, FRP or metal, but it is more difficult to hit the head than other heads when hitting. A head made of a metal material, which increases the stress generated at the neck, is more effective.

The shaft manufacturing method may be either a sheet winding method or a filament winding method, but a filament winding method is preferable because it is easy to obtain a material having a high fiber content and the physical properties are stable.

The shaft in the present invention is formed by the above-mentioned filament winding method or sheet winding method using a reinforcing fiber such as carbon fiber and a synthetic resin such as epoxy resin. The fiber constitution of the reinforcing fiber is preferably a two-layer constitution of an inner layer and an outer layer, or a three-layer constitution of an inner layer, a middle layer and an outer layer. Furthermore, in order to achieve both the twisting and bending required for the shaft, the orientation angle (winding angle) of the reinforcing fiber is ± 45 ° fiber orientation, which is effective for the twisting characteristic, in the inner layer. In order to have bending rigidity in the present invention, the fiber orientation of the outer layer is the same as the fiber orientation of the outer layer, and the fiber orientation of the outer layer is In the case of a three-layer structure consisting of an inner layer, a middle layer, and an outer layer, it is necessary to partially change the fiber orientation of the middle layer and the outer layer.

Therefore, in particular, the range from the tip to 200 mm is 0 ° to ± 20 °, the range from 200 mm to 400 mm is ± 15 ° to ± 30 °, and the shape is approximately 200 mm from the tip with a substantially equal thickness. As a result, 200 mm to 400 mm is thinner than the part 200 mm from the tip. Further, by using high-strength carbon fiber or glass fiber for the middle layer or the outer layer, it is possible to further improve the bending strength and impact strength at the position of the neck portion.

[0015]

As is apparent from the above configuration, the bending rigidity of the portion of 200 mm to 400 mm is suppressed more than the portion of 200 mm from the tip of the shaft, and the bending rigidity ratio is set as follows: tip to 200 mm / 200 mm to 400 mm = 1/1 to 2 By setting the ratio to / 1, the strength of the shaft tip portion is improved and the shaft feeling is improved.

[0016]

【Example】

 Hereinafter, embodiments of the shaft of the present invention will be described in detail with reference to the drawings. FIG. 1 is a vertical cross-sectional view showing an embodiment of a shaft according to the present invention. A tapered tubular shaft 1 composed of an inner layer 2 and an outer layer 3 has a tip end diameter of 4 on the small diameter side not shown. Torayca M40 (carbon fiber, trade name of Toray Industries, Inc.) impregnated with epoxy resin by a filament winding method on a core metal having a rear end diameter of 0.3 mm, a rear end diameter of 13.90 mm, and a total length of 1200 mm is oriented at an angle of ± 45. Specified size in degrees (wall thickness 0.47 mm from the chip to 200 mm, wall thickness 0.35 mm at the position 350 mm from the chip, wall thickness 0.25 mm at the position 700 mm from the chip, and wall thickness 1050 mm from the chip The inner layer 2 is obtained by winding up to a thickness of 0.2 mm).

Further, on the inner layer 2, a filament winding method was used to insert a trading card T700 (carbon fiber, trade name, manufactured by Toray Industries, Inc.) impregnated with an epoxy resin, and the orientation angle (θ ₁ ) is ± 10 °, the orientation angle (θ ₂ ) of the portion 3b from 200 mm to 400 mm is ± 30 °, the orientation angle (θ ₃ ) of the portion 3c from 400 mm to 1200 mm is ± 10 °, and the predetermined dimension ( The thickness of the part from the tip to 200 mm is 1.00 mm, the thickness is 0.65 mm at the position 350 mm from the tip, the thickness is 0.69 mm at the position 700 mm from the tip, and the thickness is 0. 0 at the position 1050 mm from the tip. (Execution at 63 mm) to form the outer layer 3, then tighten the whole with a polypropylene film etc. and put it in a heating furnace to heat cure and pull out the core bar. Then, the polypropylene film is peeled off, and the surface of the molded product is ground to obtain a golf club shaft.

Next, Table 1 shows the results of comparative evaluation of the shaft obtained as described above and the conventional shaft.

[0019]

[Table 1] Bending at break: Amount of breaking at three-point bending test From Table 1 above, it is clear that the shaft of the present invention has improved strength at the tip portion of the shaft and excellent shaft feeling compared to the conventional shaft.

[0020]

[Effect of the device]

 As described above, in the golf club shaft according to the present invention, the orientation angle of the fibers in the outer layer is 0 ° to ± 20 ° in the range from the small diameter end to 200 mm, and ± 15 ° in the range from 200 mm to 400 mm. The bending rigidity ratio of the above 200 mm to 400 mm and the bending rigidity of 200 mm from the small diameter end is set to 1: 1 to 2 and the bending rigidity of the tip 200 mm to 400 mm from the tip to 200 mm. By lowering the bending rigidity, the strength of the shaft tip is improved and the shaft feel is improved.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing the structure of a shaft according to the present invention.

FIG. 2 is a graph showing flexural rigidity distributions of a shaft according to the present invention and a conventional shaft.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Shaft 2 ... Inner layer 3 ... Outer layer 3a ... Outer layer tip to 200 mm portion 3b ... Outer layer 200 mm to 400 mm portion 3c ... Outer layer 400 mm to large diameter end (butt) portion I ... Bending rigidity distribution II of conventional shaft ... Shaft bending stiffness distribution according to the present invention

Claims (3)

[Scope of utility model registration request] 1. A taper tubular shaft made of fiber reinforced plastic, comprising a golf club shaft having an inner layer and an outer layer having different orientation angles with respect to the axial direction of the fiber. To 200mm from 0 ° to ± 20 °, 200mm
A shaft for a golf club is characterized in that the range of up to 400 mm is ± 15 ° to ± 30 °, and the ratio of the bending rigidity between 200 mm to 400 mm and 200 mm from the small diameter end is 1: 1 to 2. 2. The shaft for a golf club according to claim 1, wherein a club head made of a metal material is mounted on the small diameter side of the shaft. 3. The golf club shaft according to claim 1, wherein the shaft is manufactured by a filament winding method.