JPS6121876A - Method of manufacturing fiber reinforced resin hull - Google Patents

Abstract

PURPOSE:To manufacture a hull having a reinforced core by forming a recess part in a male mold, inserting a core member covered with unwoven fabric and woven cloth as reinforcing fiber while also placing similar unwoven fabric and woven cloth as reinforcing fiber between the core member and a female mold, and carrying out injection molding. CONSTITUTION:Woven cloth 20 of reinforcing fiber and unwoven fabric 22 of reinforcing fiber are placed in a molding space formed by a male mold 14 and a female mold 12. Further, a core member 26 of foamed plastic, etc. covered with unwoven fabric 28B of reinforcing fiber and woven cloth 28B of reinforcing fiber, is equally inserted in a recess part in the male mold 12. When a resin is injected from an injection port 18, the resin penetrates through the weave patterns of the woven cloths 20, 28B, into the unwoven fabrics 22, 28A, and spreads in the mold widely and uniformly, along the unwoven fabrics 22, 28A. Thereby, an FRP hull having a reinforced core can be molded by means of injection molding.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a hull made of fiber-reinforced resin, ie, FRP, and particularly to a method for manufacturing a hull for a small vessel such as a boat, which can employ injection molding.

2. Description of the Related Art A method of manufacturing a ship body is conventionally known in which a woven fabric of reinforcing fibers such as glass fibers and a resin such as polyester are laminated and then integrally molded in a mold.

However, in conventional methods, the injection molding method cannot be used because the pressure during resin injection presses the woven fabric against one side of the mold, preventing the resin from reaching the back side of the woven fabric. It was virtually impossible. This is because if the woven fabric is lopsided, the desired strength will not be obtained and the appearance will also be impaired.

The present invention allows the resin to be uniformly distributed with little movement of the woven fabric even when resin is pressure-injected. Therefore, even when injection molding is employed, the above-mentioned problems do not occur and products with excellent strength can be produced. The purpose is to provide a manufacturing method for a ship that can be manufactured.

According to the present invention, using a mold partially formed with a recess,
After wrapping a core material such as resin with a reinforcing fiber body in which a non-woven fabric of reinforcing fibers is arranged on one side of a woven fabric of reinforcing fibers and inserting it into the recess, resin is injected into the mold, and the core material is integrated. A method for manufacturing a fiber-reinforced resin hull is provided, which comprises molding and forming reinforcing bones using the recesses.

In this case, it is preferable that the nonwoven fabric be made of long fibers to ensure resin distribution and strength.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for manufacturing a fiber-reinforced resin hull according to the present invention will be described below with reference to the drawings.

The mold for molding the hull is equipped with a male mold 12 and a female mold 14, the periphery of which can be sealed during molding via a rubber seal 16. male type 12
An injection hole 18 for injecting the resin in the mold is provided at a desired location, and the resin is injected under pressure in the direction of arrow A.

The molding space formed between the male mold 12 and the female mold 14 has the shape of a ship's body, for example, the hull of a small vessel such as a boat.

In the manufacturing method of the present invention, first, a woven fabric 20 made of reinforcing fibers and a nonwoven fabric 22 made of reinforcing fibers positioned in an overlapping relationship on one side of the woven fabric are placed in the molding space. The peripheries of these woven fabrics and non-woven fabrics are clamped by the packing seal 16 at the same time as the mold is sealed.

Further, a recess 24 is formed in a part of the male die 12, and a core material 26 made of resin or the like wrapped in a nonwoven fabric 28A and a woven fabric 28B made of glass fiber or the like is inserted into the recess.

As the core material 26, it is preferable to use a relatively lightweight material such as foamed plastic.

Next, after the periphery of the mold is clamped and sealed, resin is injected through the injection hole 18 to form a hull made of fiber-reinforced resin, that is, FRP.

The woven fabric 20 is preferably formed into a single layer, and a layer of nonwoven fabric 22 is provided on either side of the woven fabric.

Since the method for manufacturing a resin hull of the present invention is carried out in the manner described above, the following effects can be obtained.

First, during injection molding, the woven fabric 20 is pressed against one side of the mold, that is, the inner surface of the male die in the case shown, by the elasticity of the nonwoven fabric 22, so that the woven fabric does not move significantly due to the injection pressure of the resin.

Further, the injected resin permeates through the weave of the woven fabric 20 and enters the nonwoven fabric 22. The resin leached into the nonwoven fabric 22 spreads widely and uniformly into the mold along the nonwoven fabric. Thus, according to the method for manufacturing a resin hull of the present invention,
The reinforcing fibers are held in a predetermined position within the molding space, and at the same time the resin is uniformly distributed throughout the molding space, resulting in stable quality with excellent strength and appearance, even with injection molding, which was previously difficult to implement. The hull of the ship can be molded.

Furthermore, by forming a recess in a part of the mold and inserting a core material around which fibers are wound into the recess, it is possible to easily mold a ship body with a floating body. In the case of a floating body, it is preferable to use a material with relatively low specific gravity, such as resin foam, as the core material 26 . It should be noted that if recesses 24 corresponding to the parts of the hull that require reinforcement are provided in the same manner as in the molding of the floating body, a reinforced bone hull can be easily molded. In the case of reinforced bone, a material with relatively high strength should be selected as the core material.

As explained above, according to the method for manufacturing a resin hull of the present invention, it becomes possible to mold a fiber-reinforced resin (FRP) hull by employing an injection molding method, which has been virtually impossible to implement in the past. Therefore, not only can productivity be greatly improved, but also FRP hulls of a constant quality with excellent strength and appearance can be manufactured in large quantities. Furthermore, the number of molds required to produce a certain quantity can also be reduced.

[Brief explanation of the drawing]

The drawing is an explanatory cross-sectional view of a mold for carrying out the method for manufacturing a resin hull according to the present invention. In the drawings, 12...male type, 14...female type, 20...
Reinforced fiber woven fabric, 22...Reinforced resin nonwoven fabric, 24.
...A recess provided in a part of the mold, 26...Core material, 28A1
2BB... each indicates a fiber.

Claims (1)

[Claims] A mold with a recess formed in a part is used, and a core material such as a resin is wrapped with a reinforcing fiber body in which a non-woven reinforcing fiber is arranged on one side of a woven reinforcing fiber, and the core material is inserted into the recess, and then the mold is inserted into the recess. 1. A method for manufacturing a fiber-reinforced resin hull, characterized in that a resin is injected into the hull, a core material is integrally molded, and reinforcing bones are formed by the recesses.