JPH0620036U - Internal pressure injection ring - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide an internal pressure injection ring capable of easily manufacturing a resin molded product such as a golf club shaft by an internal pressure molding method even if the mandrel is hollow and has no air discharge hole. [Constitution] Hollow part 5 that can be fitted from one end of the mandrel 1
1 and an air injection portion 52 provided outside the hollow portion. [Effect] Since the mandrel and the like are hollow and it is not necessary to form the air discharge hole, there is an advantage that the resin molded product can be manufactured by the internal pressure molding method at a lower cost than the conventional one.

Description

[Detailed description of the device]

[0001]

[Technical Field of Device]

 The present invention relates to an internal pressure injection ring, and more particularly to an internal pressure injection ring used when manufacturing a resin product such as a golf club shaft by an internal pressure molding method.

[0002]

[Prior art and problems]

 In the internal pressure molding method, as shown in FIG. 4, a hollow mandrel 1 having a taper is covered with a release layer 2 for easy release, and a prepreg 3 is wound around the release layer 2 to form a mold 4 By setting the inside of the prepreg 3, air is blown into the hollow portion C of the mandrel 1, and air is ejected from an air discharge hole 11 penetrating the hollow portion of the mandrel 1, thereby applying an internal pressure to the prepreg 3 to perform heat molding. Is the way to do it. At this time, an external pressure is applied to the molding die 4, which is advantageous in that a shaft having a smooth surface can be molded.

When manufacturing a golf club shaft by such an internal pressure molding method, it is necessary to hollow the mandrel 1 and form the air discharge hole 11 as described above. However, the hollow mandrel 1 or the air discharge hole as described above has a drawback that the cost is high.

The present invention has been made in view of the above problems, and it is possible to easily manufacture a resin molded product such as a golf club shaft by an internal pressure molding method even if the mandrel is hollow and has no air discharge hole. It is an object of the present invention to provide an internal pressure injection ring capable of

[0005]

[Means for solving problems]

 In order to solve the above problems, the internal pressure injection ring according to the present invention is characterized by comprising a hollow portion which can be fitted from one end of a mandrel and an air injection portion provided outside the hollow portion.

According to the present invention, the internal pressure injection ring is fitted into the mandrel, the mold release layer is covered so as to cover at least a part of the internal pressure injection ring, and then the prepreg is provided on the mold release layer. A resin molded product can be manufactured by putting it in a mold and injecting air from the air injection portion of the injection ring. That is, it is not necessary to make the mandrel hollow and provide an air discharge hole.

[0007]

[Specific explanation of the device]

 FIG. 1 is a schematic perspective view of an embodiment of the present invention. As is clear from this figure, the internal pressure injection ring 5 of the present invention has a hollow portion 51 for fitting into the mandrel 1. A plurality of air injection pipes 52 are provided in a cylindrical shape around the outside of the hollow portion 51. Further, one end of the internal pressure injection ring is provided with a notch 53 that is obliquely cut along the circumference.

When the internal pressure injection ring as described above is used, it is inserted into the hollow portion 51 of the internal pressure injection ring 5 from one end of the mandrel 1 as shown in FIG. In this embodiment, the end of the mandrel 1 on the side where the internal pressure injection ring 5 is inserted is slightly thin, and the outer circumference of the internal pressure injection ring 5 and the outer circumference of the mandrel 1 are flush with each other. ing. However, the shape is not limited to this, and the shape may be such that the diameter gradually increases from the tip side (thin side) to the butt side (thick side) like the ordinary mandrel 1.

After mounting the internal pressure injection ring 5 on the mandrel 1 as described above, the release layer 2 is covered so that at least a part thereof covers the outer circumference of the internal pressure injection ring 5. The release layer 2 can be, for example, a flexible tube.

After the release layer 2 is covered as described above, the prepreg 3 which is the main body of the golf club shaft is wound around the release layer 2 and set in the mold 4. After being set in the mold 4 as described above, when air is blown from the outer end of the internal pressure injection ring 5 in a heated state, the air is blown into a plurality of air injection pipes on the circumference of the internal pressure injection ring 5. 51 is provided, and at least a part of the end portion having the cutout portion 53 of the internal pressure injection ring 5 is covered with the release layer 2, so that air is injected into the release layer 2. become . Therefore, the prepreg 3 is pressed in the direction of the mold 4, and is heated and hardened in such a pressed state. The notch 53 has an effect of injecting smooth air into the inside of the release layer 2.

In the above embodiment, the air injection part was formed by providing a plurality of air injection pipes around the hollow cylindrical member, but the inner circumference of the hollow part penetrates in the longitudinal direction of the internal pressure injection ring 5. It is obvious that any material can be used as long as it has voids. For example, as a double pipe structure, it is possible to make the inner penetrating portion a hollow portion 51 and the outer penetrating portion an air injecting portion.

In the above description, the golf club shaft has been described as an example, but the internal pressure injection ring of the present invention is not limited to this, and the internal pressure for manufacturing the resin molded product as described above is injected. It is obvious that it can be widely used as a component that works.

[0013]

[Effect of device]

 As described above, according to the internal pressure injection ring of the present invention, since the mandrel and the like are hollow and it is not necessary to form the air discharge hole, the resin molded product can be internally pressure molded at a lower cost than the conventional one. There is an advantage that it can be manufactured by the method.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of an internal pressure injection ring of the present invention.

FIG. 2 is a sectional view of a main part of an internal pressure injection ring of the present invention.

FIG. 3 is a cross-sectional view illustrating a method of manufacturing a golf club shaft by an internal pressure molding method using the internal pressure injection ring of the present invention.

FIG. 4 is a sectional view for explaining a method for manufacturing a golf club shaft by an internal pressure molding method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mandrel 11 Air discharge hole 2 Release layer 3 Prepreg 4 Mold 5 Internal pressure injection ring 51 Hollow part 52 Air injection part 53 Notch part

Claims (1)

[Scope of utility model registration request] 1. An internal pressure injection ring comprising: a hollow portion that can be fitted from one end of a mandrel; and an air injection portion provided outside the hollow portion.