JPS6266912A - Manufacture of closed cross-sectional structural material composed of fiber-reinforced composite material - Google Patents

Abstract

PURPOSE:To obtain a closed cross-sectional structural material composed of FRP which is high-quality and is high in reliability by reducing production cost and production time, by a method wherein a core member having an uneven surface is covered with the FRP by providing the core member on a closed cross section forming part along with arrangement of the FRP within a mold and the closed cross-sectional structural material composed of the FRP is compressed through heating. CONSTITUTION:A mold whose temperature and compression pressure, for example, are set at 130 deg.-140 deg.C and 5-100kg/cm<2> respectively is constitutied of a top force 6 and bottom force 5 and FRP is mounted on the bottom force 5. When compression molding of the FRP is performed, FRP 3 (under a dotted line) is formed. Then a core material 2 is mounted and the FRP is mounted on the same. the compression molding is performed by lowering the top force 6 under this state. In this instance, for example, SMC (Sheet molding compound) requires 2-5min and requires an epoxy material, 1-2hr. FRP 1 and the core material 2 after compression molding can get resin of the FRP entering a concave port of the surface of the core material to improve strength and rigidity of closed cross-sectional structure.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for manufacturing a closed cross-section structure made of IIi reinforced composite material (hereinafter referred to as FRP).

Conventional technology In recent years, fiber and i-reinforced composite materials have been used in various fields, and because they are lightweight, have great strength, and are easy to mold, they are also applied to automobiles.
As shown in Japanese Patent No. 706, fiber-reinforced composite materials are also used in suspension arms provided at the rear of front-wheel drive automobiles.

As can be seen from Figure 3, this type of suspension arm has left and right arm sections parallel to each other, and front and machine side beam sections that face each other in the longitudinal direction of these arm sections and are close to each other in the center, which are integrally formed into a bow tie. It has upper and lower frames made of shaped fiber-reinforced composite material, and a torque tube 1 is formed in the front beam part. The torque tube is formed to provide the frame with the necessary bending and torsional rigidity, and has a closed cross-sectional structure.

In this case, the suspension arm is generally manufactured by heating and compression molding the upper and lower frames using FRP, respectively, and then aligning the upper and lower frames with adhesive. Therefore, if a closed cross-section structure is used, there are problems such as not only increasing the number of manufacturing steps but also reducing the reliability of the bond due to variations in the adhesive strength of the bonded parts and requiring multiple molds. Ta.

Problems to be Solved by the Invention Therefore, the present invention has been developed to solve these conventional problems by reducing the number of manufacturing steps by heating and compressing in a mold, and reducing the manufacturing cost. It is an object of the present invention to provide a manufacturing method capable of obtaining a high-quality and highly reliable open cross-section structure made of FRP with reduced waiting time.

Means for solving the problem, that is, the present invention comprises a step of arranging FRP in a mold, a step of arranging a core material having an uneven surface in a closed section form part, and a step of further arranging FRP. After completing these steps, the mold is heated and compressed to integrally compression mold the FRP and the core material.

Therefore, according to the process of the present invention, FRP is placed in a mold, a core member with an uneven surface is placed in a closed cross-section forming part, and covered with FRP, and the m cross-section structure of FRP is heated and compressed with the mold. Since the manufacturing process is made using FRP, the number of steps and process time are greatly reduced, and since the surface of the core member has irregularities in the closed cross-sectional structure, the bonding surface with FRP becomes larger, and the bonding force between the two increases, and at the same time, the bonding area In addition, when using the closed cross-section structure of the tube as a torque tube, bending rigidity and torsion can be improved by selecting the core member.
The stiffness can be changed appropriately.

Example The present invention will be explained below according to the embodiments shown in the drawings.

Figure 1 shows an R11m11-sided structure made of FRP manufactured by the manufacturing method according to the present invention, and this structure is used for parts such as airplanes and automobiles, as well as sporting goods such as golf equipment, fishing rods, yachts, and rackets. Since the applications in which FRP is used are widely diversified, a wide range of choices can be made in terms of the shape and material of the closed cross-sectional structure.

FIG. 2 shows core 02. The core material 2 should preferably be one that does not deform under pressure and should have an uneven surface. Therefore, it is possible to use either a three-dimensional fabric or a tea towel structure in which the outer and inner members are different.

In this example, the mold temperature was 130'' to 140°C, the compression pressure was 5 to 100 Kg/cIR2, and the upper mold 5
and a lower mold 6, and the FRP is placed on this lower mold 5. When this FRP is compression molded, the FRP below the dotted line in Figure 1
3.

Next, place the core material 2 and FRP'&li< on top of it.

In this state, when the upper mold 6 is lowered and compression molded, the result is as shown in Fig. 1, and 3 M (:, (5hear n+
(oldingCOIDOund) 2 to 5 minutes for compression molding, 1 to 2 hours for epoxy molding.

The FRPI and core material 2 after molding are
P's S! Fat gets in.

Effects of the Invention As described above, according to the present invention, the two members sandwiching the core material as in the conventional method can be replaced with agent II or the like. There is no need to bond the two parts together, and there is no need for the process of sandwiching and bonding the core material after the two parts are heated and compression molded separately, so the number of molds and processes can be reduced, and combined with the uneven surface of the core material, It is possible to improve the strength and rigidity of a closed cross-section structure made of FRP.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing a method for manufacturing a 11N cross-section structure made of FRP according to the present invention, FIG. 2 is a perspective view of a core material, and FIG. 3 is a perspective view showing a conventional automobile suspension arm. 1.3.4...FRP, 2...Core material, 5...Lower mold, 6...Upper mold.

Claims (1)

[Claims] The process includes a step of arranging a fiber-reinforced composite material in a mold, a step of arranging a core material having an uneven surface in a closed cross-section forming part, and a step of further arranging a fiber-reinforced composite material, and after completing these steps, the mold is A method for manufacturing a closed cross-section structure made of a fiber-reinforced composite material, characterized in that the fiber-reinforced composite material and the core material are integrally compression-molded by heating and compressing the fiber-reinforced composite material.