JP3413357B2 - Golf club shaft - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a shaft for a golf club.

[0002]

2. Description of the Related Art Conventionally, as for a golf club shaft, there is known a technique for adjusting a kick point by connecting shaft materials having different elasticity in the longitudinal direction, as disclosed in Japanese Patent Publication No. 6-26638. Has been. For example, when molding a shaft by winding a prepreg in which reinforcing fibers are impregnated with synthetic resin, by joining and winding multiple prepregs with different elastic moduli of reinforcing fibers in the axial direction, the kick point and kick point It is disclosed that the curve can be adjusted.

[0003]

However, in practice, it is difficult to adjust the kick point only by joining and winding the prepregs having different elastic moduli in the axial direction. There is a drawback that the variation in strength becomes large.

The present invention has been made based on the above-mentioned drawbacks, and an object of the present invention is to provide a golf club shaft that efficiently achieves performance adjustment in the axial direction and that prevents reduction in strength and increase in variations. To do.

[0005]

Means for Solving the Problems The above-mentioned problems are divided by splitting a main body prepreg forming a main body layer of a golf club shaft in the axial longitudinal direction and winding the ends so as to abut each other. Each prepreg wrapped around is thick
Are different from each other, the elastic modulus of the reinforcing fiber or the wound formed
This is achieved by forming the prepreg having the higher bending elastic modulus of the layer into a thin wall thickness .

As described above, regarding the prepreg divided in the front-rear direction, by increasing the elastic modulus of the reinforcing fiber of the thin prepreg or the bending elastic modulus of the wound layer, the abutting portions of the front and rear prepregs are increased. The rigidity difference and the strength difference can be suppressed within a certain range, and the performance can be efficiently adjusted in the axial direction.

[0007]

1 is a view showing the overall shape of a golf club, in which a head 3 is attached to the tip of a shaft 1 and a grip 5 is attached to the base. The shaft 1 is configured by winding a plurality of prepregs, and in this embodiment, as shown by the cross-sectional shape of FIG. 2, prepregs (CP) in which reinforcing fibers are aligned in the circumferential direction are used.
An inner layer 10 made of prepreg), an intermediate layer 20 made of prepreg (AP prepreg) in which reinforcing fibers are aligned in a direction inclined with respect to the axial direction, and a prepreg (SP prepreg) made of aligned reinforcing fibers in the axial direction. It is constituted by the outer layer 30.

Each layer is formed by a CP prepreg (circumferential direction fiber layer) 11 in which the inner layer 10 is wound once, as shown in the laminated structure of FIG. 3 and the prepreg arrangement configuration example of FIG.
The outer layer 30 is wound twice by the AP prepreg (oblique direction fiber layer) 21 and 22 in which the intermediate layer 20 is wound twice.
P prepreg (axial length direction fiber layer) 31 and 1 each
SP prepreg (fiber layer in axial direction) 32,3 to be wound
It is composed of three. The CP prepreg 11, the AP prepregs 21 and 22 and the SP prepregs 31 to 33 described above are prepregs (main body prepregs) that form the entire length direction of the shaft and form a main body layer.

In each of the above-mentioned prepregs, the AP prepreg is such that the prepregs in which the reinforcing fibers are aligned in the inclination direction cross the inclination directions (preferably ±).
(45 degrees) Two sheets are superposed on each other, and the twisting strength can be improved in any twisting direction. In addition to these main body prepregs, the prepregs are partially wound to reinforce necessary parts. That is, in the region where the head at the tip end is attached, the auxiliary prepregs 41 and 42 in which the reinforcing fibers are aligned in the axial direction are arranged on the inner layer side and the outer layer side, and the portion where the grip at the base end is attached is the outer layer side. The auxiliary prepreg 45 in which the reinforcing fibers are aligned in the axial direction is
Each is wound for reinforcement.

According to the present invention, at least one or more of the main body prepregs are divided in the axial direction, and the ends thereof are in abutting shape (or at predetermined intervals).
It is wound around the core metal M. In this case, the laminated structure of the main body prepreg and the structure of the main body prepreg divided in the axial direction are appropriately changed. That is, the laminated structure of the prepreg of the shaft shown in FIGS. 3 and 4 is merely an example, and the number of prepregs used, the number of windings, the wall thickness, the resin impregnation amount, the alignment direction of the reinforcing fibers, and the elasticity. The rate and the like can be variously changed according to the required characteristics of the golf club and the like.

Specifically, for example, the main body prepreg can be configured as follows. Circumferential fiber layer 1
1 is not necessary. Further, a prepreg may be wound around the surface of the outermost layer 33 to form a surface layer thinner than the axial fiber layer. The CP prepreg 11, the SP prepreg 31, and the surface layer prepreg (not shown) may be separately overlapped with the CP prepreg. With this configuration, it is possible to prevent crushing and improve strength. The diagonal fiber layers 21 and 22 have a total of 4 layers, but normally 2
It may be wound in the range of 6 layers. Further, a part thereof may be separated somewhere in the axial length direction fiber layers 31 to 33, or the oblique direction fiber layers 21 and 22 may all be arranged on the outer layer side. With this structure, the torsional strength can be improved. In addition, the axial length direction fiber layers 31 to 33 are four layers in total, and it is preferable that the number of axial fiber layers 31 to 33 be within the range of 2 to 6 layers.

[0012]

EXAMPLES Specific examples of the present invention will be described below. The following examples will be specifically described with reference to the laminated structure of the shaft shown in FIG. 3 and the structure of the prepreg shown in FIGS. 4 to 6 as necessary. (1) The main body prepreg forming the main body layer is divided into front and rear in the axial direction, and the ends thereof are abutted and wound around the core metal M. In this case, the prepregs divided into the front and the rear have different wall thicknesses, and the prepreg having the higher elastic modulus of the reinforcing fiber or the higher bending elastic modulus of the wound layer is made thinner. That is, when the elastic modulus of the reinforcing fiber of each prepreg which is divided into front and rear and wound or the bending elastic modulus of the layer formed by winding is E1 and E2, and the wall thickness is T1 and T2, E1 <
A prepreg satisfying the requirements of E2 and T1> T2 is wound in an abutting shape.

Specifically, for example, as shown in FIG.
The SP prepreg 32 forming the main body prepreg is divided into front and rear in the axial direction to form a front prepreg 32a and a rear prepreg 32b. Each prepreg 32a, 3
2b is in a state of being cut in a direction orthogonal to the core metal M, and each end 32c is abutted and wound. In this configuration, the prepregs 32a and 32b have different wall thicknesses and flexural moduli, and the prepreg having a higher elastic modulus of the reinforcing fiber or the flexural modulus of the wound layer is made thinner. There is. Then, in the configuration as shown in the figure, by forming the rear prepreg 32b with high elasticity and thin wall thickness, it is possible to efficiently manufacture a lightweight shaft having a beam. Also, the front prepreg 32a
The high elasticity and thin thickness of the shaft makes it possible to obtain a sharp and flexible shaft.

As described above, in the structure in which the main body prepreg is divided in the axial direction, by making the prepreg having the higher bending elastic modulus a thin wall thickness (the higher strength has a larger wall thickness), the rigidity difference between the abutting portions is increased. It is possible to efficiently reduce the weight and improve the specific rigidity by suppressing the strength difference within a certain range. In addition,
When actually winding, the front prepreg 32a and the rear prepreg 32b may be attached to the prepreg 33 so that the end portions of the front prepreg 32a and the rear prepreg 32b abut against each other. In this case, by winding the prepreg 33 so as to be on the inner side, the meandering of the reinforcing fibers of the divided prepreg is prevented, and the strength can be improved and stabilized. Alternatively, when the prepreg 33 is used as a polishing stock, the prepreg 33 may be wound so as to be on the outside. Further, the prepreg 33 is configured by aligning the reinforcing fibers in the axial direction, but a CP prepreg, a woven fabric, a resin sheet made of a resin, or the like may be used. For rate and wall thickness,
There is no limitation. However, by making the prepreg 33 thinner and thinner than the prepregs 32a and 32b, the characteristics of the prepreg 32a and the prepreg 32b become more remarkable.

Further, in the above structure, the abutting portion may be provided at a plurality of positions in the axial direction, and the main body prepreg divided into front and rear in the axial direction may extend over a plurality of sheets. Further, the alignment directions of the fibers of the prepreg divided in the axial direction may be different. (2) The main body prepreg that forms the main body layer is divided into front and rear in the axial direction, and its ends are wound around the core metal M together with other main body prepregs with a predetermined interval. In this case, as shown in FIG. 5, in the main body prepreg 50 divided into the front and the rear, the opposite ends form an angle Θ with the axial direction.
They are formed and wound in a state of being separated by a predetermined distance d.

In this way, the ends of the divided prepregs are butted against each other in the axial direction and are arranged at a predetermined interval, and the prepregs are wound together with the other main body prepregs to form a kick point. For example, the amount of bending at the position where the bending is desired to be emphasized can be relatively increased. Moreover, actual manufacturing becomes easy.

In the configuration shown in FIG. 5, the angle Θ with respect to the axial direction is approximately 20 to 70 degrees, and the distance between the ends may be 1 to 100 mm. However, the front and rear of the prepreg is to prevent them heavy. Further, in such a configuration, since the divided prepregs have unstable positional relationship during manufacturing, it may be wound after being attached to an ultrathin sheet having substantially the same shape as the main body prepreg. preferable.

Also in this configuration example, the prepregs to be disassembled in the front and rear direction may be different from each other in thickness and flexural modulus. (3) The main body prepreg that forms the main body layer is divided into front and rear in the axial direction, the ends of the front and rear prepregs are abutted, and an ultrathin sheet as indicated by reference numeral 32d in FIG. 4 is attached to the abutted portion. Then, it is wound around the core metal M together with the other main body prepreg. In this case, the ultra-thin sheet 32d can be formed into a sheet shape, a tape shape, a film shape, or the like,
It is made of synthetic resin or fiber reinforced synthetic resin. When reinforcing fiber is mixed, it is not possible to limit the load, so it is better to configure it in the form of woven fabric or non-woven fabric. Since the resin impregnation amount must have high adhesiveness, the main body prepreg It is preferable that the amount is more than

As described above, since the front and rear prepregs are not overlapped with each other, a large uneven thickness is generated, rigidity anisotropy,
It is possible to prevent the meandering of the fibers of the outer prepreg, and to suppress the decrease in strength. Further, in the axial direction, the strength of the butted portion where the fibers are cut can be improved, and prepregs having different thicknesses and elastic moduli are wound,
The physical property difference in the longitudinal direction can be efficiently adjusted.

The connection of the front and rear prepregs using such an ultra-thin sheet can also be applied to the configuration examples of (1) and (2) described above, and the prepregs are butted to each other. The facing portions may be butted to each other or partially to each other. (4) The main body prepreg that forms the main body layer is divided into front and rear in the axial direction, the front and rear prepregs are wound so that the ends thereof are in abutting shape, and the thickness of each prepreg is different and the prepreg is wound. The core metal M is wound so that the number of times is an integral number. That is, as shown in FIG. 6, when the main body prepreg 60 is divided into, for example, three pieces in the axial direction, the divided prepregs 60a to 60c have different wall thicknesses and each prepreg is wound an integral number of times. To be done.

In the above structure, the prepregs are
It may be connected with an ultrathin sheet 32d as shown in FIG. 4 or may be attached to another main body prepreg. In addition, each prepreg forms a lap margin within a range not exceeding 0.3 ply (-0.2 to +0.3 in consideration of manufacturing variations) due to the lap margin when wound. Keep it.

With this configuration, it is possible to prevent an increase in uneven thickness at the abutting portion and to change the thickness of the shaft in the axial direction in stages. As a result, it is possible to obtain a shaft which has little directivity and can exhibit desired physical properties remarkably in the axial direction of the shaft. (5) The main body prepreg that forms the main body layer is divided into front and rear in the axial direction, the front and rear prepregs are wound with their ends abutting each other, and a core is formed by combining prepregs having different bending elastic moduli and wall thicknesses. Wind around gold M.

For example, by increasing the thickness difference between the prepregs before and after the axial direction in the axial direction to be larger than 1.5 times (preferably in the range of 2 to 4 times), it is possible to obtain characteristics such as a large difference in rigidity and a weight reduction. To be Alternatively, if it is desired to reduce the strength difference or the rigidity difference in the axial direction, or to reduce the meandering of the fibers, it may be set to 1.5 times or less.

Further, three or more kinds of prepregs may be wound in the axial direction, and the characteristics such as thickness, elastic modulus and fiber direction may be changed stepwise according to the axial direction. Or 3
The characteristics of the prepreg in the intermediate region among the prepregs of at least one kind may be made larger or smaller than various characteristics of the prepregs before and after the intermediate area. Further, materials having different specific gravities and compressive strengths may be arranged in stages along the axial direction.

With the above structure, the performance can be efficiently adjusted in the axial direction of the shaft. By greatly changing the bending elastic modulus difference and the wall thickness difference between the front and rear prepregs, it is possible to increase the performance difference in the axial direction, and by increasing the bending elastic modulus difference and reducing the wall thickness difference, It is possible to obtain a shaft having a stable structure with little variation in strength. The configurations (1) to (5) described in detail above can be implemented in an appropriate combination.

[0026]

According to the present invention, performance adjustment in the axial direction of the golf club shaft can be efficiently achieved.
It is possible to prevent a decrease in strength and an increase in variations.

[Brief description of drawings]

FIG. 1 is a diagram showing an overall shape of a golf club.

FIG. 2 is a partial vertical sectional view of a shaft portion.

FIG. 3 is a cross-sectional view showing an example of a laminated structure of prepregs forming a shaft.

FIG. 4 is a view showing an arrangement configuration example of prepregs for obtaining the golf club shaft having the laminated structure shown in FIG.

FIG. 5 is a diagram showing one configuration example of a main body prepreg that forms a golf shaft.

FIG. 6 is a diagram showing another configuration example of a main body prepreg forming a golf club.

[Explanation of symbols]

1 shaft 11,2,22,31,32,33 Main body prepreg

Claims (4)

(57) [Claims] 1. A main body prepreg forming a main body layer of a golf club shaft is divided into front and rear in the axial direction, and its end portions are wound so as to abut each other, and the divided prepregs are wound. The wall thickness is different from each other,
The elastic modulus or the flexural modulus of the wound layer is higher.
A golf club shaft having a thin prepreg. 2. A main body prepreg that forms a main body layer of a golf club shaft is divided into front and rear in the axial direction, and its end portions are wound together with other main body prepregs with a predetermined interval, The main body prepreg divided into two parts has opposite ends that form a predetermined angle with respect to the axial direction.
A golf club shaft, which is formed and wound around a predetermined distance. 3. Each prepreg which is divided and wound.
It is in claim 1, characterized in that the number of turns is an integer times
The described golf club shaft. 4. Each prepreg which is divided and wound.
Is that the ultra-thin sheet is attached and wound integrally.
The golf club shaft according to any one of claims 1 to 3, which is regarded as a characteristic .