CA2028373C

CA2028373C - Golf club construction

Info

Publication number: CA2028373C
Application number: CA002028373A
Authority: CA
Inventors: Kun-Nan Lo
Original assignee: Individual
Current assignee: Individual
Priority date: 1990-10-17
Filing date: 1990-10-23
Publication date: 1994-10-04
Anticipated expiration: 2010-10-23
Also published as: DE4034393C2; FR2669233B1; FR2669233A1; AT396336B; AU621247B1; AU6478790A; CA2028373A1; ATA209590A; BE1004640A3; DE4034393A1

Abstract

A novel golf club construction is provided herein. It includes a club head and a shaft. The club head has a tapering neck. The shaft has a lower end extending into the club head and passing through the neck. The golf club construction further has a cured resin impregnated fibrous material wrapping around the shaft and an adjacent portion of the shaft in a fashion that provides a gradually decreasing cross-section from the neck to the shaft. The cured resin impregnated fibrous material wrapping integrally interconnects the club head and the shaft by cohesive bonding upon being heated and pressurized. There is thus no visible seam at the joint between the club head and the shaft.

Description

202~373 This invention relates to a golf club construction, and particularly to the neck portion of a golf club which interconnects the head and the shaft of the golf club.
Conventionally, the head of a golf club is connected to the shaft by receiving one end of the shaft in the socket of a neck portion of the head and applying an adhesive to the joint of the neck and the shaft. Generally, the club heads are made of wood, or metals such as stainless steel and other alloys, or composite plastic materials such as fiber reinforced plastics. However, the shafts are never wooden anymore.
Metallic club heads are generally strong, hard and tough. Such heads are connected to composite plastic shaft just by applying an adhesive to the joint of the shaft and the neck of the head as shown in Figure 1.
The strength of the joint depends on the total strength of the adhesive, the neck and the golf shaft.
A wooden or composite plastic head has poorer strength, hardness and toughness than metallic heads.
In order to reinforce the joint of such a head and the shaft, synthetic cords are wound around the neck of the head as shown in Figure 2 after the neck is connected to the shaft. In addition, the neck as well as the socket in the neck should be lengthened so that the

2~28373 shaft can extend more deeply into the head.
The joints formed by the methods mentioned above are generally liable to loosen when subjected to torsion forces created by striking balls. When the neck and the shaft are made of different materials, serious deformation might be caused at the joint. In many cases, the neck or the shaft breaks at their joint.
An object of a principal aspect of this invention is to provide a golf club which has a strong part that interconnects the head and the shaft, such strong part being capable of enduring a large torque.
The present invention provides, in a broad aspect thereof, a golf club construction comprising a club head and a shaft; the club head having a tapering neck; the shaft having a lower end extending into the club head passing through the neck; the golf club construction further having a cured resin impregnated fibrous material wrapping around the shaft and an adjacent portion of the shaft in a fashion that provides a gradually decreasing cross-section from the neck to the shaft, the cured resin impregnated fibrous material wrapping integrally interconnecting the club head and the shaft by cohesive bonding upon being heating and pressurized, and whereby there is no visible seam at the joint between the club head and the shaft.
In the accompanying drawings:
Figure 1 shows the joint of the head and the shaft of a golf club of the prior art;

t ll Figure 2 shows the joint of the head and the shaft of another golf club of the prior art;
Figures 3 and 4 show a first embodiment of the invention; and Figures 5 and 6 show a second embodiment of the invention.
Referring to Figures 3 and 4, the first embodiment of the golf club of one aspect of the invention includes a head 10, a neck 11 and a shaft 20, which are formed simultaneously in a mold by using a resin impregnated fibrous material, e.g., an epoxy resin impregnated woven or non-woven fabric. The fabric may be made of glass fibres or carbon fibres. In fabrication, the resin-impregnated woven fabric layers are wrapped around a core substantially to form the shape of a golf club head including a neck in a conventional way. The shaft 20 is fabricated by wrapping resin-impregnated woven fabric layers into a cylinder or other suitable form to fashion a rod continuing from the 2~

the wrapping process, the fibers of the fabric layers are oriented properly so as to achieve the maximum possible strength golf club. The resulting unfinished article is then placed in a suitable mold and heated until the resin impregnated woven fabric layers are cured. The golf club so formed has no joint between the head 10 and the shaft 20 and therefore can endure a large torque.
A second embodiment of the invention is shown in Figures 5 and 6, having a golf club head 10' with a neck 11' and a shaft 20' which are separate pieces.
The head 10' and the neck 11' are fabricated by using a resin impregnated fibrous material as in the first embodiment. The shaft 20' is also fabricated by using the same material. However, the head 10' and the shaft 20' are respectively cured and formed in two moids.
After the head and the shaft are fabricated, a bore 12' is provided in the neck 11. The shaft is jointed to the neck 11' by fitting the end 21' of the shaft 20' into the bore 12'.
Afterwards, the joint of the shaft 20' and the head 10' are wrapped with a resin impregnated fibrous material 40 which may be the same as the material used to fabricate the head 10' and the shaft 20'. Then, the resin impregnated fibrous material 40 is cured by heating and pressurizing it in a suitable die. The cured resin impregnated fibrous material 40 cohesively bonded to the shaft 20' and the head 10', thereby strengthening the joint between the shaft and the head.

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS
FOLLOWS:

1. A golf club construction comprising a club head and a shaft; said club head having a tapering neck; said shaft having a lower end extending into said club head passing through said neck; said golf club construction further having a cured resin impregnated fibrous material wrapping around said shaft and an adjacent portion of said shaft in a fashion that provides a gradually decreasing cross-section from said neck to said shaft, said cured resin impregnated fibrous material wrapping integrally interconnecting said club head and said shaft by cohesive bonding upon being heated and pressurized, and whereby there is no visible seam at the joint between said club head and said shaft.