JPH0321581A - Manufacture of member in three-dimensional form - Google Patents

Abstract

PURPOSE:To carry out manufacture easily and quickly by filling the inside of a female die with a foaming substance while a soft sheet is interposed, foaming it and taking out of the female die, then putting a foaming sheet, etc., on the outside of the mentioned foamed substance, and accommodating this substance again in the female die followed by a thermal hardening process. CONSTITUTION:In manufacturing, first bi-sected dies 31, 31' are provided whose inside assumes the shape of the intended product, and soft sheets 32, 32' are affixed to the inner surfaces. The inside of thse dies 31, 31' is filled with a foaming substance, which is allowed to foam and harden. Then the substance is taken out of the dies, and the soft sheets 32, 32' are exfoliated from the inner surfaces. Thus a molding is obtained, in which the foaming material 2 is in tight contact with the periphery of a skeleton 1. From above the skelet 1 and foaming substance 2, a foamed sheet and continuous fiber impregnated with resin are placed, and the dies are tightened again, and the whole is heated to accomplish a three-dimensionally shaped final product 33.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a method for manufacturing a structure made from a synthetic resin (hereinafter referred to as FRP) having a structure reinforced with continuous fibers. This is a method that can easily manufacture structural members having original shapes, and is suitable for, for example, manufacturing bicycle frames.

(Prior art) Generally, when manufacturing a member with a complex three-dimensional shape using FRP, a foam material that has already been foamed and is often divided into two or more is placed inside, and then resin is placed on top of it. A method has been used in which continuous fibers impregnated with the same material are laminated, mold-clamped, and heat-cured.

In order to produce a member having a desired three-dimensional shape, there is a method of laminating or winding continuous fibers impregnated with resin, but these materials are generally expensive and have poor working efficiency. As a means of solving these problems, there is a method of using an inexpensive foam material. However, according to the conventional technology, it is necessary to process the foamed foam into the desired shape, and from the viewpoint of the strength and aesthetics of the frame joint part,
If it is necessary to fit foam material to the outside of the joint that already exists, a gap will inevitably occur between the foam material and the joint, or between the foam materials. This will require a lot of effort.

(Problems to be Solved by the Invention) The present invention has been made in view of the above problems, and an object of the present invention is to provide a manufacturing method that can easily mold a complicated three-dimensionally shaped member. Furthermore, the aim is to simplify post-processing by using foam material to obtain something close to the final shape.

(Means for Solving the Problems) That is, the present invention provides a method for manufacturing a member having a three-dimensional shape by laminating continuous fibers impregnated with a resin.
A female mold with the inside shaped like a product is prepared in advance, and a soft sheet is pasted on the inner wall of the female mold.The foaming material raw material is supplied into the mold and foamed, and then the foamed molded product is taken out from the female mold and made into a soft sheet. After peeling off the sheet, a foam sheet and then resin-impregnated continuous fibers are laminated on the outside of the foam rod, and then the mold is clamped using the female mold described above, and the whole is subjected to a heat curing treatment. There are a wide range of methods for producing members with characteristic three-dimensional shapes.

The female mold, whose inner side is shaped like a product, is usually made of a rigid object such as metal or FRP, and is preferably a split mold for ease of demolding.

Moreover, the reason why a foamed molded article is produced using a foamed material is to easily realize a curved shape and to save on expensive reinforcing fibers. The material of the foam material is not particularly specified, and conventionally known materials can be used. For example, urethane is suitable.

The soft sheet is preferably made of wax or the like and is so soft that it does not easily follow the curved surface inside the mold, and has a thickness of 1 to 3 m. In other words, it is desirable to select a thickness of the above-mentioned soft sheet that is comparable to the final thickness of the FRP laminated as the outermost layer, because continuous fibers impregnated with resin are clamped and molded with a rigid mold. This is to ensure that the surface of the final product obtained is smooth and the dimensions are accurate. As the continuous fiber impregnated with a resin serving as a raw material, so-called FRP, which is a continuous fiber of carbon, organic, or glass impregnated with a thermosetting resin such as epoxy or unsaturated polyester, is used.

As a foamable sheet, in order to create a rigid mold by applying foaming pressure from the inside of the resin-impregnated continuous fibers in conjunction with the above-mentioned mold clamping action, foaming is performed by applying heat treatment. A resin sheet that hardens is suitable, such as an epoxy film adhesive. For lamination on the surface of a foam molded article, it is desirable that the foam sheet 1 be coated with an adhesive or that it itself has adhesive properties. However, the lack of adhesion is not an essential problem in the present invention.

(for production) The above will be specifically explained using the drawings.

Half-split mold 31 with the inner side shown in Fig. 1a as a product shape
Prepare a soft sheet 32. inside it. 32' (Figure b is a cross-sectional view of the mold). Only the half-split mold 31 is applied to the core portion, the foaming material raw material is supplied into the mold, the other half-split mold 31' is applied, and the mold is tightened. Or half type 31. It is also possible to supply the foaming material raw material into the mold through the gap between the two parts 31'. After the foam material has hardened, the mold is removed and a soft sheet 32.
Peel off 32'. At this time, the cross section of the molded member is obtained in a form in which the foamed molded body 2 is tightly attached around the framework 1, as shown in FIG. A foamed sheet and resin-impregnated continuous fibers are laminated or wrapped over the foam molded body and framework to form a half-split mold 31. 31' and tighten the mold (d in the same figure). The whole is heated and hardened into a half-split mold 31.
By demolding 31', a final product having the three-dimensional shape shown in the figure e can be obtained.

(Example) Hereinafter, a case will be described in which a lug portion of a bicycle is manufactured using the method of the present invention.

Figure 2 shows the skeleton of the bicycle frame body, and the metal vibe 1
1, 12. 13 and continuous carbon fiber reinforced plastic pipes 21, 22, 23. 24 is an overall view of the structure fixed within the holder. FIG. 3 is an enlarged view of the head lug section. A two-split wooden mold having the same dimensions and shape as the final molded product is made, and based on the wooden mold, a female continuous fiber-reinforced plastic mold 28 as shown in FIG. Prepare 26'. And the mold 28 shown in the figure. Paste a 3lII1 thick wax sheet as a soft sheet on the inner wall of 28' and apply only the half-split mold 2B to the core of the frame. Next, pour the urethane foam material into the mold and place it in the other half mold 2.
Align 6′ and tighten the mold.

After the foaming material raw material is foamed and cured, it is removed from the mold to obtain a foamed molded product with a shape close to that of the final product. Next, peel off the wax sheet from the mold. A sheet of epoxy-based foam adhesive approximately 2 mm thick and carbon fiber impregnated with epoxy resin are laminated on the cured foam molding, and the core portion is again molded into mold 28. 26'
Apply and tighten the mold.

Thereafter, a heat curing treatment is performed at 120° C. for 2 hours and the mold is removed. Through this series of operations, a member having a complicated three-dimensional shape as shown in FIG. 5 can be easily manufactured, and a structure having a complicated curved surface and a smooth surface, such as the bicycle frame mentioned as an example, can be provided. I can do it.

(Effects of the Invention) The manufacturing method of the present invention makes it possible to easily and quickly manufacture members having complex three-dimensional shapes, and to supply structures with high reliability in terms of strength and rigidity. .

[Brief explanation of drawings]

The drawings show embodiments of the present invention, and FIG. 1 shows an example of a manufacturing process diagram of an FRP member having a three-dimensional shape.
The figures show a skeletal diagram of the bicycle frame body, FIG. 3 shows an enlarged view of the head lug part, FIG. 4 shows a molding die diagram of the head lug part, and FIG. 5 shows a diagram of the final molded part of the head lug part. 1: Frame 2: Foamed molded body 1: Metal vipe I2: Metal pipe 13: Metal pipe 21: FRP pipe 22: FRP pipe
23: FRP vipe 24: FRP vipe
25: FRP pipe 2G, 2B': FRP mold 31, at': hard sheet 32. 32
': Molding sub-agent Patent attorney Hiroaki Tamoto (4) (ko) (d)

Claims (1)

[Claims] In a method of manufacturing a member having a three-dimensional shape by laminating resin-impregnated continuous fibers, a female mold with the inside shaped like a product is prepared in advance, a soft sheet is pasted on the inner wall of the female mold, and then, After supplying the foam material raw material into the mold and allowing it to foam, the foam molded body is taken out from the female mold and the soft sheet is peeled off.The foamed sheet is then laminated on the outside of the foam molded body, and then continuous fibers impregnated with resin are laminated on the outside of the foam molded body. A method for manufacturing a member having a three-dimensional shape, which comprises: then clamping the mold using the female mold described above, and subjecting the entire member to a heat curing treatment.