JPH0233270B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a method for manufacturing a golf shaft, and particularly to a method for manufacturing a lightweight metal shaft.

[Background of the invention]

Various materials are used for golf shafts, such as metal shafts made of aluminum or steel, and black shafts made of carbon filament, but steel shafts are superior in all respects to shafts made of other materials. It has excellent features and is widely supported not only by professional golfers but also by general golfers.
Steel shafts are generally manufactured from pipes with large diameters and thick walls by ``cold drawing'', and are subjected to processing such as cleaning and annealing after each ``drawing''. Through such processing, the pipe becomes gradually thinner, the tube wall becomes thinner, and finally it is cut to the desired length.

Generally, such a shaft has a taper that becomes narrower toward the tip and is provided with multiple steps, and by changing the spacing (pattern) of the steps, the tight point of the shaft can be changed. be able to. Currently, kick points are classified into three types: profit, dynamic, and jet steps. Further, the flexibility of the shaft is changed depending on the relationship between the pipe diameter and the pipe wall, and currently, the flex is classified into five types: X, S, R, A, and L.

In this way, golf shafts can be selected from among the five types of flex and three types of patterns mentioned above.
You can now choose the one that suits your feeling.

Recently, golf shafts are becoming lighter in weight in order to increase flight distance, and therefore the wall thickness tends to be thinner. However, if the tube wall is made thinner, the flexibility of the shaft increases, causing the shaft to flex at the moment the ball is hit, resulting in a loss of strength and the risk of not being able to achieve the desired flight distance. Furthermore, there is a possibility that the shaft may be twisted, causing the flight direction of the ball to be deviated. In order to prevent such deflection or twisting from occurring, it is necessary to increase the diameter of the shaft tube, but increasing the diameter increases the weight of the shaft, increases air resistance, and affects the appearance. It is also undesirable.

[Purpose of the invention]

The purpose of the present invention is to reduce the overall weight of the shaft by reducing the wall thickness of the shaft, and also to increase the wall thickness only at the necessary portions of the shaft without the need to increase the diameter of the shaft tube. It is an object of the present invention to provide a method for manufacturing a golf shaft that reduces or prevents deflection or twisting.

[Summary of the invention]

A method of manufacturing a golf shaft according to the present invention involves creating a tubular shaft stock with steps at desired intervals along its length to reduce or prevent the occurrence of flexing or twisting along the shaft stock. By applying a corrosion inhibitor around the area and immersing the shaft material coated with this corrosion agent in a corrosive liquid, the wall thickness of the shaft material other than the area coated with the corrosion inhibitor is reduced, and the shaft material is When the weight of the material is reduced to a predetermined weight, the shaft material is removed from the corrosive liquid and washed to stop corrosion, and then the corrosion inhibitor is removed to obtain a golf shaft that is lighter overall. It is something.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

1 to 4 show the sequential steps of the golf shaft manufacturing method according to the present invention.

FIG. 1 shows a tubular shaft blank 1 manufactured by cold drawing in a conventional manner, the shaft blank having a plurality of shaft blanks (only two shown in the figure) at desired intervals along its length. Step 22
will be provided.

According to the method of the present invention, as shown in FIG. Apply corrosion inhibitor 3 around the middle part.

Next, the entire shaft material coated with the corrosion inhibitor 3 is immersed in a corrosive solution for a certain period of time.
An acid mixture is used as the corrosive liquid. Thereby, the wall thickness of the portion 4 of the shaft material other than the portion coated with the corrosion inhibitor is reduced. When the weight of the shaft material is reduced to a predetermined weight due to this reduction in wall thickness, the shaft material is removed from the corrosive liquid and washed to stop corrosion.

Thereafter, by removing the corrosion inhibitor 3, as shown in FIG. 4, the entire shaft is made thinner and lighter, and the necessary parts of the shaft, that is, the step 2 part and the step part in the example shown in the figure, are made lighter. By increasing the wall thickness only in the intermediate section 5 of the shaft 6 and the step, a shaft 6 is created which reduces or prevents deflection or twisting.

[Action of the invention]

As described above, according to the method according to the present invention, it is possible to reduce the weight of the shaft to a desired level by reducing the wall thickness, and at the same time, it is possible to maintain strength against bending and torsion in desired portions. It is possible to manufacture a golf shaft that can extend the flight distance and does not become deviated in direction.

[Brief explanation of drawings]

FIG. 1, FIG. 2, FIG. 3, and FIG. 4 are explanatory diagrams showing sequential steps in the golf shaft manufacturing method according to the present invention. In the figure, 1 is the shaft material, 2 is the step provided on the shaft, 3 is the corrosion inhibitor, 4 is the part where the wall thickness has become thinner due to corrosion, and 5 is the part where the thickness remains between the steps. , 6 shows the finished shaft.

Claims (1)

[Claims] 1. Fabricating a tubular shaft stock with steps at desired intervals along its length, and applying a corrosion inhibitor along the shaft material around the points where the occurrence of deflection or twisting is to be reduced or prevented. death,
By immersing the shaft material coated with this corrosive agent in a corrosive liquid, the wall thickness of the shaft material portions other than the portions coated with the corrosion inhibitor is reduced, and when the weight of the shaft material decreases to a predetermined weight, the shaft material is A method for manufacturing a golf shaft, characterized in that the golf shaft is lifted from a corrosive liquid and washed to stop corrosion, and then a corrosion inhibitor is removed to obtain a golf shaft that is lighter overall.