JP2001062015A - Golf shaft - Google Patents

Abstract

(57) [Summary] [Problem] A tubular body that achieves both low torque and lightweight.
In particular, it is an object to provide a golf shaft. SOLUTION: A golf shaft formed by winding and firing a bias pattern prepreg and a straight pattern prepreg on a mandrel 4 having a main taper portion M on a tip side and a slow taper portion S on a grip side, A golf shaft having a bias pattern prepreg covering the main taper portion M and the slow taper portion S, and a bias pattern prepreg covering only the main taper portion M. According to the present invention, it is possible to achieve both low torque and light weight effectively for a golf shaft that is a tubular body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tubular body, in particular, a golf shaft made by winding a prepreg around a core material (mandrel 4) and performing firing molding.

[0002]

2. Description of the Related Art In general, the performance of a golf shaft (tubular body) has a great influence on the state of a flying ball, and therefore its development has been actively carried out. In particular, the “torsion” of the golf shaft itself is one of the major factors that have an adverse effect. A golf shaft usually twists at the time of impact, which causes a deviation in a flying direction. It is important to prevent this twist as much as possible, that is, to reduce the torque, in order to accurately determine the direction. For this reason, various improvements have been made to prevent the twist of the shaft.

[0003] For example, a combination of prepregs having different fiber directions and fiber amounts is used, or the material of the prepreg itself is changed. As the former, the use amount of the prepreg of the bias pattern is increased as much as possible, but the weight of the golf shaft is increased, which is against the weight reduction. As the latter, the use of prepregs made of ultra-high elasticity fibers has been used. However, this also has the disadvantage that the material cost is increased and the workability at the time of production is worse than that of a so-called ordinary carbon fiber prepreg.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art.
That is, an object of the present invention is to provide a tubular body, particularly a golf shaft, which achieves both low torque and light weight, or achieves both low torque and light weight.

[0005]

As a result of further studies, the present inventors have found that bias pattern prepregs are unevenly distributed in a thin portion of the shaft, which is a portion that is easily twisted, so as to increase the number of bias pattern prepregs. The present inventors have found that low torque and light weight can be satisfied at the same time by unevenly distributing the bias pattern prepreg so as to reduce the bias pattern prepreg, and completed the present invention based on this finding.

That is, the present invention is (1) formed by winding and firing a bias pattern prepreg and a straight pattern prepreg on a mandrel having a main taper portion on the tip side and a slow taper portion on the grip side. A golf shaft, comprising: a bias pattern prepreg covering the main taper portion and the slow taper portion; and a bias pattern prepreg covering only the main taper portion.

(2) A golf shaft formed by winding and firing a bias pattern prepreg and a straight pattern prepreg on a mandrel having a main taper portion on the tip side and a slow taper portion on the grip side. And a bias pattern prepreg that covers the main taper portion and the slow taper portion, a first bias pattern prepreg that covers only the main taper portion, and a shorter bias pattern prepreg.

(3) The bias pattern prepreg covering only the main taper portion, the bias pattern prepreg covering only the main taper portion, and the bias pattern prepreg covering the main taper portion and the slow taper portion. 30% by weight or more of the golf shaft according to the above (1) or (2).

(4) The above (1) or (2) wherein the taper ratio of the main taper portion is 9/1000 or more.
Golf shaft.

(5) The golf shaft according to (1) or (2), wherein the length of the main tapered portion is 90% or less of the entire length.

(6) The fiber angle of the bias pattern is 0 ° <θ <90 ° with respect to the shaft center axis.
(1) or (2). (7) The golf shaft according to the above (1) or (2), wherein the slow taper portion is straight.

(8) The golf shaft according to (1) or (2), wherein the slow taper portion includes a straight portion and a tapered portion.

(9) A golf shaft formed by winding and firing a bias pattern prepreg and a straight pattern prepreg on a mandrel having a main taper portion on the tip side and a slow taper portion on the grip side. A bias pattern prepreg that covers the main taper portion and the slow taper portion; and a bias pattern prepreg that covers only the main taper portion. 30% by weight or more of the total weight of the bias pattern prepreg covering only the taper portion, the bias pattern prepreg covering the main main taper portion and the slow taper portion, and the taper ratio of the main taper portion is 9/1000 or more; Slow taper Resides in the golf shaft, characterized in that it was straight.

(10) A golf shaft formed by winding and firing a bias pattern prepreg and a straight pattern prepreg on a mandrel having a main taper portion on the tip side and a slow taper portion on the grip side. A bias pattern prepreg covering the main taper portion and the slow taper portion, a first bias pattern prepreg covering only the main taper portion, and a bias pattern prepreg shorter than the main taper portion, and covering only the main taper portion. The bias pattern prepreg covering only the main taper portion and the bias pattern prepreg covering the main main taper portion and the slow taper portion are 30% by weight or more of the total weight of the bias pattern prepreg covering the main taper portion. Pas rate resides in the golf shaft is 9/1000 or more. The present invention can also adopt a configuration in which two or more selected from the above 3 to 8 are combined as long as this object is met.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the materials used in the method for forming a tubular body according to the present invention will be specifically described. The prepreg of the present invention is obtained by hardening a reinforcing fiber with a synthetic resin. As the reinforcing fiber, carbon fiber, glass fiber,
A thermosetting resin such as an epoxy resin, a phenol resin, and an unsaturated polyester is used as a synthetic resin that is generally used for molding a tube material of a golf shaft such as a metal fiber.

The prepreg of the present invention uses a bias pattern prepreg 1 and a straight pattern prepreg 2. The former has a fixed angle (0 °) with the golf shaft axis.
<Θ <90 °) is a prepreg having reinforcing fibers arranged so as to have (θ <90 °). Usually, 30 ° ~
Although 60 ° is used, the most effective 45 ° is adopted to keep the torque low. The latter is a prepreg having reinforcing fibers arranged along the golf shaft axis. In the present invention, the bias pattern prepreg (weight) covering only the main taper portion M is set to 30% by weight or more of the bias pattern prepreg (weight) covering the main taper portion M and the slow taper portion S. These pattern prepregs (weight) refer to the weight of the reinforcing fiber and the synthetic resin that solidifies it.

By doing so, the bias pattern prepreg can be unevenly distributed in the thin portion of the shaft, which is a portion that is easily twisted, so that the bias pattern prepreg increases.
The bias pattern prepreg can also be unevenly distributed in a portion that is not easily twisted so as to reduce the number of bias pattern prepregs. Therefore, it is possible to surely satisfy torque reduction and weight reduction at the same time. The golf shaft is manufactured by winding a prepreg around a core material (mandrel 4) coated with a release agent to form a tubular body, and then firing and decentering.

Since the golf shaft of the present invention has a feature in the amount of winding of the prepreg, the winding procedure of the prepreg will be mainly described separately below. Here, a mandrel 4 having a main taper portion M and a slow taper portion S is used. Also, this mandrel
From the viewpoint of the weight ratio between the bias pattern prepreg 1 and the straight pattern prepreg 2 and the ease of winding the bias pattern prepreg, it is preferable to use a main taper portion M having a length of 90% or less of the entire length.
More preferably, it is 60% or less.

[First Embodiment] The winding procedure in this embodiment is as shown in FIG. 1 (in the drawing, the left side is the tip side and the right side is the grip side). The main taper portion M of the mandrel 4 to be used has a taper ratio of 9/1000 or more, and the slow taper portion S is a straight portion having a taper ratio of zero.

1. First, a bias pattern prepreg 1A is wound around the main taper portion M to cover (form) it. 2. A bias pattern prepreg 1B is wound around a region including the main taper portion M and the slow taper portion S to cover both of them. 3. The straight pattern prepregs 2A and 2B are wound around the region including the main taper portion M and the slow taper portion S to cover both of them. The weight of the bias pattern prepreg 1A covering only the main taper portion M is the weight (total weight) of the bias pattern prepreg 1A + 1B covering the main taper portion M and the slow taper portion S.
30% or more. 4. An auxiliary straight pattern prepreg 3 is wound around a fixed region on the tip side of the main taper portion M. This completes the winding procedure.

Here, as a specific example, as shown in FIG. 2, the main taper portion M has a taper ratio of 10.4 /
Using the mandrel 4 of 1000, the weight of the bias pattern prepreg 1A covering only the main taper portion M in the above winding is the weight of the bias pattern prepregs 1A and 1B covering the main taper portion M and the slow taper portion S ( 67.5% of the total weight (ie 6
7.5% by weight). The length of the main taper portion M is about 56% of the entire length of the mandrel. The total shaft weight is 6
Weighs 4 grams.

[Second Embodiment] The prepreg winding procedure (1 to 4) is the same as that of the first embodiment (see FIG. 1). That is, the main taper portion M of the mandrel 4 to be used has a taper ratio of 9/1000 or more,
The slow taper portion S is a straight portion having a taper rate of zero. The weight of the bias pattern prepreg 1A covering only the main taper portion M is 30% or more of the weight (total weight) of the bias pattern prepreg 1A + 1B covering the main taper portion M and the slow taper portion S. Here, as a specific example, as shown in FIG. 2, the main taper portion M has a taper ratio of 10.4 / 10.
In the above winding, the weight of the bias pattern prepreg 1A covering only the main taper portion M is increased by using the mandrel 4 which is 00, and the bias pattern prepreg 1A,
31% of the weight (total weight) of 1B (ie 31% by weight)
And The length of the main taper portion M is about 56% of the entire length of the mandrel. The total shaft weight is 71 grams.

[Third Embodiment] The winding procedure in this case is as shown in FIG. 3 (in the drawing, the left side is the tip side and the right side is the grip side). The main taper portion M of the mandrel 4 to be used has a taper ratio of 9/1000 or more.
The slow taper portion S uses a taper of zero, that is, a straight one. The weight of the bias pattern prepregs 1A and 1a covering only the main taper portion M is three times the weight (total weight) of the bias pattern prepregs 1A + 1a + 1B covering the main taper portion M and the slow taper portion S.
0% or more.

1. First, in the main taper portion M, the first bias pattern prepreg 1A is provided to cover the main taper portion M.
And a longer second bias pattern prepreg 1a. 2. A bias pattern prepreg 1B is wound around a region including the main taper portion M and the slow taper portion S to cover both of them. 3. The straight pattern prepregs 2A and 2B are wound around the region including the main taper portion M and the slow taper portion S to cover both of them. 4. An auxiliary straight pattern prepreg 3 is wound around a fixed region at the end of the main taper portion M. This completes the winding procedure.

Here, as a specific embodiment, as shown in FIG. 2, the main tapered portion M of the mandrel 4 to be used is used.
Is a mandrel 4 having a taper rate of 10.4 / 1000.
Use Then, in the above winding, the bias pattern prepreg 1A, which covers only the main taper portion M,
The weight of the bias pattern prepregs 1A, 1a, and 1a covers the main taper portion M and the slow taper portion S.
45.1% of the weight (total weight) of 1B (ie, 45.1%).
% Weight). The length of the main taper portion M is about 56% of the entire length of the mandrel. The total shaft weight is 81 grams.

[Fourth Embodiment] The prepreg winding procedure (1 to 5) is the same as that of the third embodiment (see FIG. 3). The main taper portion M of the mandrel 4 to be used has a taper ratio of 9/1000 or more, and the slow taper portion S has a taper ratio of 6/1000 or less. The weight of the bias pattern prepregs 1A and 1a covering only the main taper portion M is 30% or more (that is, 30% by weight) of the weight (total weight) of the bias pattern prepregs 1A + 1a + 1B covering the main taper portion M and the slow taper portion S. Above).

Here, as a specific embodiment, in the above-mentioned winding, as shown in FIG.
Has a taper ratio of 10.4 / 1000
The slow taper portion S has a portion having a taper ratio of 5.2 / 1000 following the main taper portion and a straight portion other than the main taper portion. Main taper M
Bias Pattern Prepreg 1A, 1 Covering Only
The weight of the bias pattern prepreg 1A, 1a, 1 covering the main taper portion M and the slow taper portion S
45.1% of the weight (total weight) of B (ie, 45.1% by weight). The length of the main taper portion M is about 50% of the total length of the mandrel. The total shaft weight is 81 grams.

With respect to the embodiment described above, a conventional example 1.
2.3. Torque value and weight ratio R of bias pattern prepreg compared to 2.3 [P1 / (P1 + P2) × 100
(%)] Are shown in Table 1. P1: weight of the bias pattern prepreg (1A, 1a) covering the main taper portion; P2: weight of the bias pattern prepreg (1B) covering the main taper portion and the slow taper portion; P1 + P2: bias pattern prepreg covering the main taper portion And the weight (1) of the bias pattern prepreg covering the main taper portion and the slow taper portion.
A, 1a, 1B)

[Conventional Example 1] The winding procedure in this embodiment is as follows (see FIG. 5). 1. First, a bias pattern prepreg 1B is wound around a region including the main taper portion M and the slow taper portion S to cover both of them. 2. The straight pattern prepregs 2A and 2B are wound around the region including the main taper portion M and the slow taper portion S so as to cover the entire length of both. 3. An auxiliary straight pattern prepreg 3 is wound around a fixed region on the tip side of the main taper portion M.

As shown in FIG. 6, the mandrel 4 used
The main taper portion M has a taper ratio of 8/1000, and the slow taper portion S is a straight portion having a taper ratio of zero. The length of the main taper portion M is about 94% of the total length of the mandrel. The total shaft weight is 83 grams.

[Conventional Example 2] The winding procedure in this embodiment is the same as that in Conventional Example 1 (see FIG. 5). As shown in FIG. 2, the main tapered portion M of the mandrel 4 to be used has a taper ratio of 10.4 / 1000, and the slow taper portion S is a straight portion having a taper ratio of zero. The length of the main taper portion M is about 56% of the entire length of the mandrel. The total shaft weight is 83 grams.

[Conventional Example 3] The winding procedure in this embodiment is the same as that in Conventional Examples 1 and 2 (see FIG. 5). As shown in FIG. 2, the main tapered portion M of the mandrel 4 to be used has a taper ratio of 10.4 / 1000.
The slow taper portion S is a straight portion having a taper rate of zero. The length of the main taper portion M is about 56% of the entire length of the mandrel. The total shaft weight is 76 grams.

From Table 1, it can be seen that the torque of the shaft of the present invention is lower than that of the conventional shaft even if the overall shaft weight is small, so that the shaft is hardly twisted. Also, the head can be made heavy. Although the present invention has been described above, the present invention is not limited to the above-described embodiments and examples, and various modifications are possible. In the case of covering only the main taper portion, a degree that slightly covers the slow taper portion may be included. As a matter of course, the slow taper portion S may have a two-stage shape of a taper portion and a taper portion having a larger taper rate than the taper portion. The bias pattern prepreg 1 can be wound around the main taper portion M by changing the length to be covered, and can be wound in three or more patterns.

Further, the shaft of the present invention can reduce the torque even with the same weight as the conventional one, and further, can set the same torque value as the conventional one to reduce the weight.

[0035]

[Table 1]

[0036]

According to the present invention, there is an advantage that the torque of the golf shaft which is a tubular body can be effectively reduced and the weight thereof can be effectively reduced, or both can be achieved.

[Brief description of the drawings]

FIG. 1 shows a winding procedure in Examples 1 and 2.

FIG. 2 shows a mandrel used in Examples 1, 2, and 3, and Conventional Examples 2 and 3.

FIG. 3 shows a winding procedure in Examples 3 and 4.

FIG. 4 shows a mandrel used in Example 4.

FIG. 5 shows a winding procedure in Conventional Examples 1, 2, and 3;

FIG. 6 shows a mandrel used in Conventional Example 1.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Bias pattern prepreg 1A ... Bias pattern prepreg 1a ... Bias pattern prepreg 1B ... Bias pattern prepreg 2 ... Straight pattern prepreg 2A ... Straight pattern prepreg 2B ... Straight pattern prepreg 3 ... Auxiliary straight pattern prepreg 4 ... Mandrel M ... Main taper Part S: Slow taper part

Claims (10)

[Claims] 1. A golf shaft formed by winding and firing a bias pattern prepreg and a straight pattern prepreg on a mandrel having a main taper portion on a tip side and a slow taper portion on a grip side. A golf shaft comprising a tapered portion, a bias pattern prepreg covering the slow taper portion, and a bias pattern prepreg covering only the main taper portion. 2. A golf shaft formed by winding and firing a bias pattern prepreg and a straight pattern prepreg on a mandrel having a main taper portion on a tip side and a slow taper portion on a grip side, wherein the main taper is provided. And a bias pattern prepreg covering the slow taper portion, a first bias pattern prepreg covering only the main taper portion, and a shorter bias pattern prepreg. 3. A bias pattern prepreg covers only the main tapered portion, said main tapered portion bias pattern prepreg and a main tapered portion covers only a Surotepa section and the total weight of the 30% of the cover to bias pattern prepreg The golf shaft according to claim 1, wherein: 4. A taper ratio of a main taper portion is 9/100.
The golf shaft according to claim 1, wherein the value is 0 or more. 5. The golf shaft according to claim 1, wherein the length of the main tapered portion is 90% or less of the entire length. 6. The golf shaft according to claim 1, wherein the fiber angle of the bias pattern satisfies 0 ° <θ <90 ° with respect to the shaft center axis. 7. The golf shaft according to claim 1, wherein the slow taper portion is straight. 8. The golf shaft according to claim 1, wherein the slow tapered portion includes a straight portion and a tapered portion. 9. A golf shaft formed by winding and firing a bias pattern prepreg and a straight pattern prepreg on a mandrel having a main taper portion on the tip side and a slow taper portion on the grip side, wherein A bias pattern prepreg that covers the taper portion and the slow taper portion, and a bias pattern prepreg that covers only the main taper portion, and the bias pattern prepreg that covers only the main taper portion covers only the main taper portion 30% by weight or more of the total weight of the bias pattern prepreg to cover the main taper portion and the slow taper portion, the taper ratio of the main taper portion is 9/1000 or more, and the slow taper portion is straight. Specially Golf shaft to be featured. 10. A golf shaft formed by winding and firing a bias pattern prepreg and a straight pattern prepreg on a mandrel having a main taper portion on a tip side and a slow taper portion on a grip side, wherein the main taper is provided. And a bias pattern prepreg covering the slow taper portion, a first bias pattern prepreg covering only the main taper portion, and a shorter bias pattern prepreg covering the main taper portion, and a bias pattern prepreg covering only the main taper portion. The total weight of the bias pattern prepreg covering only the main taper portion and the bias pattern prepreg covering the main taper portion and the slow taper portion is 30% by weight or more, and the taper ratio of the main taper portion is 9/1000 or more. A golf shaft, comprising: