JPS6138032B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of molding a composite material plate in which a reinforcing fiber cloth such as glass fiber is impregnated with a resin such as polyethylene.

Conventionally, this type of molding method, as seen in Japanese Patent Publication No. 47-27796, involves heating sheet-shaped reinforcing fibers coated with resin and then sequentially laminating them, and then pressing the laminates with compression rolls. A method is provided in which the material is compression molded and then cooled using a cooling roll.

According to this conventional method, the laminate is only under pressure while it is being applied to the compression rolls, and after passing through the compression rolls, it expands. Therefore, the amount of resin attached increases according to the amount of expansion, and the content of reinforcing fibers is approximately 70%V.
(volume %) is the limit. In other words, the amount of expensive resin used increases. Moreover, there is a possibility that bubbles will be generated again in the laminate during expansion.

An object of the present invention is to provide a method for molding a composite material plate that can greatly increase the fiber content and reduce the amount of resin used, and can also be molded while maintaining a sufficiently defoamed state. be.

In order to achieve the above object, the method for forming a composite material plate of the present invention involves laminating a reinforcing fiber cloth, a thermoplastic resin sheet, and a thin metal plate coated with a release agent on both sides with the thermoplastic resin sheet in between. After connecting the inner end of the thin metal plate of this laminate to the mandrel, this laminate was wound around the mandrel while applying tension, and in a vacuum chamber, with tension and vibration applied, A high-frequency voltage is applied between the outer edge of the thin metal plate and the core metal, and the thermoplastic resin sheet is melted by dielectric heating to impregnate the reinforcing fiber cloth, and then cooled.

An embodiment of the present invention will be described below based on the drawings.

In Figure 1, 1 is a reinforced fiber cloth such as glass fiber, polyester fiber, or carbon fiber, 2 is a thermoplastic resin sheet made from polyester resin, nylon resin, polypropylene resin, etc., and 3 is a sheet with a mold release agent coated on both sides. These 1,
2 and 3 are formed into a laminate 5 through a plurality of guide rollers 4 with the thermoplastic resin sheet 2 as an intermediate, and then wound around a mandrel 6. The winding is carried out so that the reinforcing fiber cloth 1 is on the outside, the thermoplastic resin sheet 2 is in the middle, and the thin metal plate 3 is on the inside. is applied. Further, the metal thin plates 3 are heated by a heating device 8 before lamination. During winding, the inner end 5a of the laminated plate 5 is inserted into the groove 9 of the mandrel 6, as shown in FIG. 2, so that the inner end of the thin metal plate 3 is connected to the mandrel 6. As shown in Figure 2, after winding, the mandrel 6
is fixedly supported by a bracket 12 within a vacuum chamber 11 formed by the partition wall 10, and the bracket 12 is attached to the inner surface of the partition wall 10 via a vibrator 13. and the outer end 5 of the laminate 5
A tension force is applied to b by a spring 14. In this state, the inside of the vacuum chamber 11 is absorbed and degassed by the vacuum pump 15, and the vibrator 13 is operated. Further, a high frequency voltage is applied from a high frequency power source 16 between the outer end of the thin metal plate 3 and the mandrel 6. As a result, the thermoplastic resin sheet 2 is melted by dielectric heating, and the reinforcing fiber cloth 1 is impregnated with the melted resin liquid. At this time, the inside of the reinforcing fiber cloth 1 is suctioned and degassed, and is further subjected to vibration, so that the impregnation is sufficiently carried out without generating bubbles. Furthermore, the gap that is likely to occur due to impregnation is absorbed because the laminate 5 is tightened by the tension force of the spring 14. After sufficiently dissolving and impregnating,
Now let it cool. By peeling off the gold layer thin plate 3 in a slightly cooled state, a spiral-shaped composite material plate can be obtained. To use this composite material plate for a secondary purpose, it can be heated again to soften it and processed in the next step.

Note that before lamination, chopped strands may be supplied to the reinforcing fiber cloth 1 and laminated, or pellet resin may be supplied to the thermoplastic resin sheet 2 and laminated.

As described above, according to the present invention, the thermoplastic resin sheet is melted by dielectric heating while the laminate wound around the mandrel is under tension, and the melted resin liquid is applied to the reinforcing fiber cloth. A composite material plate can be easily obtained by impregnating the metal, followed by cooling and peeling off the metal sheet. In this way, impregnation and cooling are performed while applying tension and maintaining compression pressure, so no expansion occurs, and the amount of resin used can be extremely reduced, while the content of reinforcing fibers can be greatly increased ( about
60%V) is possible. In particular, the dissolution and impregnation is carried out under conditions where compression pressure is maintained under tension and further under conditions where vibration is applied under vacuum, so that it can be carried out satisfactorily without generating any bubbles.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, with FIG. 1 being a schematic side view when laminating, and FIG. 2 being a side view when dissolving and impregnating. DESCRIPTION OF SYMBOLS 1... Reinforced fiber cloth, 2... Thermoplastic resin sheet, 3... Metal thin plate, 5... Laminate, 6... Core metal, 7... Tension roller device, 8... Heating device, 11... Vacuum chamber, 13...vibrator, 1
4... Spring, 16... High frequency power supply.

Claims (1)

[Claims] 1. Laminate a reinforcing fiber cloth, a thermoplastic resin sheet, and a thin metal plate coated with a release agent on both sides with the thermoplastic resin sheet in the middle, and connect the inner end of the metal thin plate of this laminate to the core metal. , this laminate is wound around a mandrel while applying tension, and in a vacuum chamber, under tension and vibration, a high frequency voltage is applied between the outer edge of the thin metal plate and the mandrel. A method for forming a composite material plate, which is characterized by melting a thermoplastic resin sheet by dielectric heating, impregnating it into a reinforcing fiber cloth, and then cooling it.