JPH09117968A - Tube material and production thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce an FRP tube material having rib like reinforcing parts in its hollow part so that the integration properties of the reinforcing parts and a tube main body are excellent, the reinforcing parts are not detached from inner wall and the irregularity is not generated at the arranging positions of the reinforcing parts. SOLUTION: Riblike FRP reinforcing parts 6 stretched across the inner wals of a tube main body 4 along an axial direction are arranged to the FRP tube made body 4 to form a tube material 2 wherein the tube main body 4 and the reinforcing parts 6 are integrally formed. This tube material 2 can be obtained by inserting prepregs into the gap parts of the mandrel formed so that the gap parts having the shapes corresponding to the reinforcing parts 6 and winding prepregs around the mandrel in the state being in contact with the prepregs inserted into the gap parts and heating and curing the prepregs.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an FRP pipe material used for a golf club shaft and the like and a method for manufacturing the same. The present invention relates to a pipe material having improved buckling strength and a manufacturing method thereof.

[0002]

2. Description of the Related Art In recent years, as a shaft for a golf club,
FRP products (so-called black shafts), which mainly contain carbon fibers as fiber reinforcements, are often used. This FRP shaft is usually manufactured by winding a sheet-like prepreg obtained by impregnating parallel rovings with a thermosetting resin around a mandrel, heating and curing the prepreg, and then removing the mandrel. ing.

A golf club shaft has a bending strength,
High buckling strength is required. Therefore, in order to improve the bending strength and the buckling strength of the FRP shaft described above, the prepreg is generally wound so that the fiber orientation direction forms a large angle with the shaft axis of the shaft in a part or the whole of the shaft axial direction. Carbon layer (bias layer)
Is adopted, or a means for providing a layer made of a material having high compressive strength and tensile strength in a concentrated manner at a portion where the bending strength is to be strengthened.

The former measure is intended to improve the strength by designing the thickness of the carbon layer and the fiber orientation direction, and the latter measure is intended to improve the strength by designing the material. However, with these methods, the bending strength of the shaft,
The buckling strength mainly depends on the type, amount and orientation angle of carbon fiber and the type of high strength material, and there is a limit to the degree of freedom in design for improving strength.

On the other hand, in order to increase the degree of freedom in design for improving the strength, a technique of fixing a reinforcing material in the hollow portion has been proposed as a means for improving the strength of the shaft by utilizing the hollow portion in the shaft. It is (actually developed 53-62464
issue). FIG. 5 shows this technique. In the figure, 52 is a pipe body of a shaft, 54 is a reinforcing member made of plastic or the like having a cross-shaped cross section, and 56 is an adhesive for fixing the reinforcing member 54 to the inner wall of the pipe body 52. It is an agent.

[0006]

However, the golf club shaft shown in FIG. 5 has the following drawbacks because the reinforcing material is adhered to the inner wall of the tube body with an adhesive. . (A) Since the adhesive is interposed between the inner wall and the reinforcing material, the integrity of the pipe body and the reinforcing material is not sufficient, and the reinforcing material does not contribute sufficiently to the improvement of strength. Therefore, the desired bending strength and buckling strength may not be obtained even if the reinforcing material is used. (B) The reinforcing material may come off from the inner wall due to defective adhesion, resulting in a defective product. (C) Since the reinforcing member is manufactured by inserting the reinforcing member into the hollow portion of the pipe main body and adhering the reinforcing member to the inner wall, it is difficult to make the position of the reinforcing member uneven, and it is difficult to make the product uniform.

The present invention has been made in view of the above circumstances, and is excellent in the integrity of the reinforcing portion in the hollow portion and the pipe body, the reinforcing portion contributes sufficiently to the improvement of strength, and the reinforcing portion is detached from the inner wall. It is an object of the present invention to provide an FRP pipe material that does not have any variation and does not cause variations in the arrangement position of the reinforcing portion, and a manufacturing method thereof.

[0008]

In order to achieve the above-mentioned object, the present invention has a rib-shaped FRP reinforcing portion extending in the axial direction and hung between a hollow portion of an FRP pipe main body and an inner wall of the pipe main body. Is provided, and the pipe body and the reinforcing portion are formed integrally with each other.

Further, according to the present invention, a rib-shaped FRP reinforcing portion extending along the axial direction and provided between the inner walls of the FRP pipe main body is disposed in the hollow portion of the FRP pipe main body, and the FRP pipe main body is reinforced with the pipe main body. In the method of manufacturing a tubular member integrally formed with a portion, a prepreg is inserted into the void portion of the mandrel in which a void portion having a shape corresponding to the reinforcing portion is formed inside along the axial direction,
Further, the present invention provides a method for producing a pipe material, which comprises winding a prepreg around a mandrel in a state of being in contact with the prepreg inserted in the void and then heating and curing the prepreg.

There is no limitation on the type of FRP forming the pipe material of the present invention, and any one having an arbitrary structure can be used according to the purpose. For example, as the fiber reinforcement, carbon fiber,
One or more of glass fiber, metal fiber, aramid fiber, silicon carbide fiber, alumina fiber, boron fiber, etc., as the resin, thermosetting resin such as epoxy resin, phenol resin, unsaturated polyester resin, polyamide, polycarbonate, etc. One or more kinds of thermoplastic resins and the like, and catalysts, accelerators, fillers, release agents, etc. can be used as auxiliary materials. When the tubular member is a golf club shaft, it is suitable to use carbon fiber, boron fiber as the fiber reinforcing material, epoxy resin, phenol resin, or unsaturated polyester resin as the resin, but not limited to this. .

In the pipe material of the present invention, the shape and size of the pipe body and the reinforcing portion can be appropriately determined according to the purpose. For example, the pipe body has a cylindrical shape, an elliptic cylindrical shape, a rectangular cylindrical shape, or the like, and the reinforcing portion is It can be formed in an arbitrary shape such as an X shape, an I shape, or a Y shape in cross section. In addition, the position where the reinforcing portion is provided is not limited, and the reinforcing portion may be provided at a part in the axial direction of the pipe body, or may be provided over the entire portion. When the tubular member is a golf club shaft, the tubular body is formed in a slightly tapered cylindrical shape, and a reinforcing portion having an X-shaped, I-shaped, or Y-shaped cross section is easily broken in the tip portion of the shaft or It is suitable to be provided in the grip portion, but not limited to this.

In the method of manufacturing a pipe material according to the present invention, a mandrel in which a void having a shape corresponding to the reinforcing portion is formed is used. Examples of the method for producing such a mandrel include, for example, a means for forming a void along the axial direction from an end of a solid mandrel to a part or almost the whole of the mandrel, and fixing the mandrel by combining a plurality of divided bodies. In addition to the above, it is possible to employ a means or the like for forming a void along the axial direction of a shape corresponding to the reinforcing portion between each divided body.

The prepreg used in the manufacturing method of the present invention includes, for example, a sheet-shaped one prepared by impregnating a fiber-reinforced material such as rovings, cloths and mats arranged in parallel with a thermosetting resin. You can

[0014]

1 (A) to 1 (C) each show a preferred embodiment of a pipe material according to the present invention, and these pipe materials 2 are used as shafts for golf clubs.
In these pipe materials 2, 4 is a slightly tapered cylindrical FRP pipe main body, and 6 is an FRP reinforcing portion arranged in the hollow portion of the pipe main body 4. The reinforcing portion 6 is a rib-like member extending between the inner walls of the pipe body 4 along the axial direction, that is, (A) has an X-shaped cross section (cross shape), and (B) has an I-shaped cross section.
(C) has a Y-shaped cross section, and the reinforcing portion 6 and the pipe body 4 are integrally formed. Further, the reinforcing portion 6 is arranged in one or both of the tip portion of the pipe body 4 and the grip portion. Among the pipe materials 2 of FIG. 1, for example, the pipe material 2 of (B) provided with the reinforcing portion 6 having an I-shaped cross section has a bending strength of about 15 to 25% and a buckling strength as compared with a pipe material having no reinforcing portion 6. Is about 20%, and the pipe members 2 of (A) and (C) provided with the reinforcing portion 6 having an X-shaped cross section and a Y-shaped cross section are further improved in bending strength and buckling strength. .

[0015]

Next, the present invention will be specifically described by way of examples, but the present invention is not limited to the following examples. FIG. 2 is a partially omitted perspective view showing the tip of the mandrel used for manufacturing the pipe material shown in FIG. This mandrel 12 divides the tip portion of the solid mandrel into four divided portions 14 by cutting a portion up to 30 cm from the tip of the solid mandrel along the axial direction, and between these divided portions 14. The X-shaped void portion 16 is formed along the axial direction.

The procedure for manufacturing the pipe material of FIG. 1 (A) using the mandrel of FIG. 2 is as follows, for example. Two prepregs 22 cut into a predetermined shape as shown in FIG. 3 are inserted into the space 16 of the mandrel 12.
In this case, the prepreg 22 is folded at a right angle at the position indicated by the dotted line, and both prepregs 22 are bent at the mandrel 1
It is inserted into the gap 16 so as to be in contact with the center of 2 (see FIG. 4). If necessary, the prepreg 22 and the gap 16
Another prepreg may be inserted between the prepreg and the peripheral wall. At this time, it is appropriate that the fiber orientation angle of the prepreg 22 inserted into the space 16 is 45 to 90 degrees, especially about 90 degrees with respect to the axial direction of the mandrel. It is possible to obtain a pipe material having high strength.
In addition, the portion 2 protruding from the void portion 16 of the prepreg 22
4 is pressed against the peripheral surface of the mandrel 12.

The fixing jig 18 is inserted into the tip of the space 16 of the mandrel 12 (see FIG. 2). The fixing jig 18 is
It is formed in an X-shaped cross section corresponding to the shape of the void portion 16, and holds the shape of the void portion 16 by preventing the respective divided portions 14 of the mandrel 12 from moving. Each plate portion 20 of the fixing jig 18 is dimensioned such that the tip end surface thereof is located inward of the peripheral surface of the mandrel 12 when it is inserted into the void portion 16, so that it is fixed at the time of manufacturing the pipe material. Jig 1
8 does not come into contact with the prepreg wound around the mandrel 12.

A prepreg in which the fiber orientation direction is parallel to the mandrel axis, a prepreg in which the fiber orientation direction forms an angle with the mandrel axis, and the like are appropriately wound around the mandrel 12. At this time, prepreg 2
The portion 24 protruding from the void 16 of the mandrel 12 of FIG.
Since it is pressed against the peripheral surface of the mandrel 12, the prepreg 22 inserted into the space 16 and the prepreg wound around the mandrel 12 are in contact with each other. The outer circumference of the wound prepreg may be wrapped with a wrapping tape made of polypropylene or the like.

After the prepreg is cured by heating, the fixing jig 18 is removed from the mandrel 12, and the mandrel 12 is further removed from the cured product. As a result, FIG. 1 (A)
The FRP pipe material shown in is completed.

[0020]

As described above, the present invention has the following effects. (a) In the pipe material of the present invention, the pipe main body and the reinforcing portion in the hollow portion are integrated, and since no adhesive agent is interposed between the inner wall and the reinforcing portion, the reinforcing portion sufficiently contributes to strength improvement. . Therefore, desired bending strength and buckling strength can be obtained by the reinforcing portion. (b) In the pipe material of the present invention, since the pipe body and the reinforcing portion are integrated with each other, the reinforcing portion does not come off from the inner wall to cause a defective product. (c) The pipe material of the present invention can be manufactured by inserting the prepreg into the void portion of the mandrel, further winding the prepreg around the mandrel, and then heat-curing the prepreg, so that the arrangement position of the reinforcing portion varies. It is possible to easily achieve product uniformity. (d) According to the manufacturing method of the present invention, it is possible to easily manufacture the FRP pipe material in which the pipe main body and the rib-shaped reinforcing portion in the hollow portion are integrated.

[Brief description of the drawings]

1 (A) to 1 (C) are cross-sectional views showing a preferred embodiment of the pipe material of the present invention.

FIG. 2 is a partially omitted perspective view showing an example of a mandrel used for manufacturing the pipe material of the present invention.

FIG. 3 is a front view showing an example of a prepreg to be inserted into a void portion of a mandrel.

FIG. 4 is a cross-sectional view showing a state in which a prepreg is inserted in a void portion of a mandrel.

FIG. 5 is a cross-sectional view showing an example of a conventional pipe material with a reinforcing material.

[Explanation of symbols]

 2 Pipe material 4 Pipe body 6 Reinforcement part 12 Mandrel 16 Void part 18 Fixing jig 22 Prepreg

Claims (2)

[Claims] 1. A rib-shaped FRP reinforcing portion extending in the axial direction, which is hung between the inner walls of the FRP pipe main body, is arranged in the hollow portion of the FRP pipe main body, and the pipe main body and the reinforcing portion are integrated. A pipe material characterized by being formed in. 2. A rib-shaped FRP reinforcing portion extending in the axial direction, which is hung between the inner walls of the FRP pipe main body, is provided in the hollow portion of the FRP pipe main body, and the pipe main body and the reinforcing portion are integrated. A method of manufacturing a pipe material formed in, wherein a prepreg is inserted into the void portion of a mandrel in which a void portion having a shape corresponding to the reinforcing portion is formed along the axial direction inside, and further inserted into the void portion. A method for producing a pipe material, which comprises winding a prepreg around a mandrel in a state of being in contact with the prepreg and then heating and curing the prepreg.