GB2323043A

GB2323043A - Golf club shaft

Info

Publication number: GB2323043A
Application number: GB9704964A
Authority: GB
Inventors: Chin-San You
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-03-11
Filing date: 1997-03-11
Publication date: 1998-09-16
Anticipated expiration: 2017-03-11
Also published as: GB9704964D0; FR2760975B3; FR2760975A3; DE29704399U1; GB2323043B

Abstract

A fibre-reinforced plastics golf club shaft is constituted by two inner layers of unidirectionally laid reinforcing fibres which are laid at an angle to each other and to the axis of the shaft. The inner layers are then covered by either (Fig. 2) a tape of unidirectional fibres or (Fig. 4) a braided tube of fibres.

Description

GOLF CLUB FIELD OF THE INVENTION The present invention relates generally to a golf club, and more particularly to a reinforced and lightweight golf club.

BACKGROUND OF THE INVENTION The conventional golf clubs are generally made of a metal material or a fiber-reinforced plastic composite material. The golf clubs of the metal material are relatively heavy and poor in elasticity, and are therefore gradually replaced by the golf clubs of the fiber-reinforced plastic composite material.

The conventional golf clubs of the fiber-reinforced plastic composite material are made of a plurality of the braided fiber materials, which are arranged in a parallel manner before they are impregnated with an appropriate amount of thermoplastic or thermosetting resin to form a platelike fiber fabric plate on which a tapered long rod is disposed. The tapered long rod is then rolled in a predetermined direction such that the fiber fabric plate is wound around the tapered long rod, and that the fiber fabric plate is caused to have a tapered construction, and further that the tapered fiber fabric plate is then heated to take form.

In view of the fact that the fiber fabric plate has a length and a width, both sides along the axis of the tapered long rod are vulnerable to severance. The structural integrity of the severed fiber braids is therefore undermined seriously. The conventional method for overcoming such a deficiency as described above is to employ a fiber fabric plate of a greater width so as to increase the winding number of the fiber fabric plate to enhance the structural strength of the golf club. However, such a practice of widening the fiber fabric plate as referred to above is likely to bring about a substantial increase in the cost of making the golf club as well as the increase in the weight of the golf club.

SUMMARY OF THE INVENTION It is therefore the primary objective of the present invention to provide a strong and lightweight golf club, which can be made at a reasonable cost.

it is another objective of the present invention to provide a golf club which is properly reinforced.

In keeping with the principle of the present invention, the foregoing objectives are attained by a golf club, which is composed of an inner tube and an outer tube. The inner tube is made of a tapered wound body having a plurality of first fiber braids and second fiber braids. The outer tube is composed of a plurality of third fiber braids which are wound around the inner tube to prevent the severance of the inner tube at such time when the inner tube is subjected to stress. In addition, the outer tube may be also reinforced by a plurality of fourth fiber braids and fifth fiber braids to strengthen the club uniformly and to smooth the surface of the club.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a perspective view of the inner tube of a first preferred embodiment of the present invention.

FIG. 2 shows a perspective view of the outer tube of the first preferred embodiment of the present invention.

FIG. 3 shows a partial enlarged portion of the first preferred embodiment of the present invention.

FIG. 4 shows a perspective view of a second preferred embodiment of the present invention.

FIG. 5 shows a partial enlarged portion of the outer tube of the second preferred embodiment of the present invention.

FIG. 6 shows another perspective view of the second preferred embodiment of the present invention.

FIG. 7 shows a perspective view of a third preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION As shown in FIGS. 1 and 2, a golf club 10 embodied in the present invention has a large diametrical end 12 and a small diametrical end 13.

The golf club 10 of a tapered construction is composed of an inner tube 14 and an outer tube 15.

The inner tube 14 is made up of a plurality of first fiber braids 41 and second fiber braids 42, which are impregnated with the thermosetting resin. The first fiber braids 41 are parallel to one another such that they form a predetermined angle a along with the axis of the golf club 10. The second fiber braids 42 are also arranged in a similar manner. The first and the second fiber braids 41 and 42 may be adhered together to one piece body or separately to two piece bodies before they are wound to form the inner tube 14.

The outer tube 15 is made of third fiber braids 43. The inner tube 14 is first wound around a tapered rod 16 before the outer tube 15 is wound around the inner tube 14 such that the outer tube 15 has an appropriate pitch, as illustrated in FIG. 2, and that the outer tube 15 is wound repeatedly to eliminate the pitch gap. The outer tube 15 enables the club 10 to have a uniform structural strength. In addition, the outer tube 15 is capable of preventing the severance of a vulnerable portion 40 located around the fringe of the inner tube 14. The vulnerable portion 40 is susceptible to damage caused by stress.

The angles formed by the axis of the tapered rod 16 and the third fiber braids 43 corresponding in location to the large diametrical end 12 and the small diametrical end 13 may be variable. In order to strengthen the small diametrical end 13, a considerably small angle may be formed between the axis of the tapered rod 16 and the third fiber braids 43 located at the small diametrical end 13.

As shown in FIG. 3, there is a head 50 formed between the outer surface of the inner tube 14 and the pitch portion in view of the thick third fiber braids 43. As a result, the golf club 10 tends to have a number of recesses on its outer surface. The outer tube 15 can not be made easily and economically.

In order to smooth the outer surface of the golf club 10, the outer tube 15 is reinforced by a plurality of fourth fiber braids 44 and fifth fiber braids 45 such that they form together a long cylindrical net 15', which is then impregnated with the thermosetting resin and is capable of expanding. As the fiber braids 44 and 45 are in natural state, they form respectively with the longitudinal axis of the club 10 an appropriate initial angle ss, as shown in FIGS. 4 and 5.

As illustrated in FIG. 6, when the outer tube 15' is joined with the inner tube 14, the outer tube 15' corresponding to the large diametrical end 12 is expanded such that the initial angle ss is changed to a first angle 6 1 which is greater than the initial angle P.

The outer tube 15' is coated with OPP and is baked along with the inner tube 14, OPP is shrinked during the heating process so as to cause the outer tube 15' corresponding to the small diametrical end 13 to attach to the outer surface of the small diametrical end 13. As a result, the above-mentioned initial angle ss is changed to a second angle 6 2 which is slightly smaller than the initial angle P.

The golf club 10 with the netted outer tube 15' has the following features.

The inner tube 14 is reinforced by the fourth and the fifth fiber braids 44 and 45 of the outer tube 15' such that the severance of the vulnerable portion 40 located around the fringe of the inner tube 14 is minimized.

The longitudinal axis of the golf club 10 forms a relatively small angle & 61 along with the fourth and the fifth fiber braids 44 and 45 which are corresponding in location to the small diametrical end 13. As a result, the structural strength of the small diametrical end 13 is effectively reinforced.

If the inner diameter of the outer tube 15' is equal to the outer diameter of the small diametrical end 13, the longitudinal axis of the golf club 10 forms a first angle & 1 along with the fourth and the fifth fiber braids 44 and 45 which are corresponding in location to the large diametrical end 12. The first angle 6 1 is slightly greater than the initial angle P In the meantime, the second angle 6 2 formed in relation to the small diametrical end 13 is equal to the initial angle ss, but smaller than the first angle 6 1.

As shown in FIG. 7, the golf club 10 of the present invention may be composed of two outer tubes 15 and 15' , in addition to the inner tube 14. It is suggested that the netted outer tube 15' is fitted over the outer tube 15 so as to enable the golf club 10 to have a greater structural strength and a smooth outer surface.

Claims

WHAT IS CLAIMED IS:

1. A golf club comprising: a tapered inner tube formed of a plurality of first fiber braids impregnated with resin and of second fiber braids impregnated with resin, said inner tube being wound in a predetermined direction and having a small diametrical end and a large diametrical end; and an outer tube formed of a plurality of third fiber braids and wound around said inner tube such that an axis of a golf club forms an angle with each of said third fiber braids which are wound around said small diametrical end and said large diametrical end.

2. The golf club as defined in claim 1, wherein said angle formed in relation to said small diametrical end is smaller than said angle formed in relation to said large diametrical end.

3. A golf club comprising: a tapered inner tube formed of a plurality of first fiber braids impregnated with resin and of second fiber braids impregnated with resin, said inner tube being wound in a predetermined direction and having a small diametrical end and a large diametrical end; and a netted outer tube formed of a plurality of fourth and fifth fiber braids and wound around said inner tube such that an axis of a golf club forms a first angle with each of said fourth and fifth fiber braids which are wound around said large diametrical end, and that said axis of said golf club forms a second angle with each of said fourth and fifth fiber braids which are wound around said small diametrical end, said first angle being greater than said second angle.

4. The golf club as defined in claim 3 further comprising an outer tube located between said inner tube and said netted outer tube, said outer tube being formed of a plurality of reinforcing fiber braids.

5. The golf club as defined in claim 1, wherein the angle formed between said axis and each of said third fiber braids wound around said small diametrical end is smaller than the angle formed between said axis of said golf club and each of said third fiber braids wound around said large diametrical end.

6. A golf club substantially as hereinbefore described with reference to the accompanying drawings.