JPS5920635A - Manufacture of cushion member - Google Patents

Abstract

PURPOSE:To manufacture a cushion member having a sharp shape, by injecting foamable resin into a molding die into which a skin material formed of thermoplastic resin softened by heating is inserted, and by molding the skin material monolithically under the foaming pressure. CONSTITUTION:A hollow skin material 2 formed of thermoplastic resin softened by heating is inserted into a molding die 1 composed of splits, and after the lower end of the material 2 is closed up, foamable resin 3 is injected into the material. Next, while heating is made to a foaming temperature, the pressure inside the molding die 1 is lowered through the intermediary of a pressure reducing pipe 1A so as to foam the resin 3. The skin material 2 is swollen by the foaming pressure of the resin 3, and thus a cushion member 4 formed of a skin material 2A and a cushion material 3A is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing members having cushioning properties such as headrests and seats of automobiles.

This type of cushion member usually consists of a skin material and a cushioning material housed inside the skin material.

Conventionally, to manufacture such cushioning members, a method has been used in which the skin material is first manufactured by blow molding, sewing, etc., and then a foamable plastic material is injected into the skin material and foamed to form the cushion material. It is being However, this method requires a two-step process of forming the skin material and then forming the cushioning material, and since the molded skin material is flexible, it is easily deformed by the foaming pressure when forming the cushioning material, and is sharp. It has drawbacks such as the difficulty of manufacturing products with a specific shape.

The present invention aims to improve the above-mentioned conventional drawbacks and provide a method for manufacturing cushion members in one step, preventing deformation of the product, and easily manufacturing products with sharp shapes. The main idea is to expand and mold the skin material using the foaming pressure applied during the process.

To explain the present invention with reference to an embodiment shown in the drawings, the mold (1) is a split mold, and a hollow skin material (2) in a heat-softened state is inserted into the dispersed mold (1) (Fig. 1). ). The skin material (2) is made of thermoplastics such as polyethylene, polypropylene, polyvinyl chloride, etc.

The lower end of the skin material (2) is then closed and the foamed plastic material (3) is injected (FIG. 2). Expandable plastic materials include, for example, expandable urethane prepolymers, expandable plastisols, expandable plastic melts, and the like. The foamable plastic material (3) can be foamed as it is or by heating to an appropriate foaming temperature. Thus, the foaming pressure causes the skin material (2) to swell 1
1 is molded to become skin material 2)A, and at the same time skin material (2)
Cushion material (3) A is formed inside A (Figure 3)
. At this time, if the pressure inside the mold (1) is reduced using the pressure reducing pipe (1)A, the skin material (2) will be bulged more smoothly and its shape will be sharper.

The cushion member (4) is thus manufactured, and if necessary, after cooling, the mold (1) is opened and taken out.

The mold (1) during molding may be heated or cooled. However, since the skin material (2) is in a heated and softened state, even if the mold (1) is cooled, the skin material (2)
) The foaming of the foamable plastic material (3) is promoted by the heat of the foaming material (3).

Except for this example, the skin material (2) does not necessarily have to be in the shape of a hollow bag, but is inserted into the mold (1) in the form of a sheet, and foamed by injecting the foamable plastic material (3) from one side. You can also force it (Figure 4). In Figure 4 (5)
is a stopper that closes the lower end of the mold (1).

Since the present invention has the above-described structure, the skin material made of thermoplastic plastic in a heat-softened state in the mold is expanded and molded by the foaming pressure when the foamable plastic material is foamed to form a cushioning material. It becomes a skin material, and cushion members can be manufactured in one step. At this time, the foaming of the foamable plastic material can be promoted by the heat of the skin material. Furthermore, since the skin material and the cushioning material are formed simultaneously in the mold, the product shape is regulated by the mold and is sharp without deformation.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a cross-sectional view of the mold with the skin material inserted, FIG. 2 is a side cross-sectional view of the mold when the foamable plastic material is injected, and FIG. FIG. 4 is a sectional side view of the mold when manufacturing is completed, and FIG. 4 is a sectional side view of the mold when manufacturing of another embodiment is completed. In the figure (1)...molding mold (2)...skin material (
3)...Foamable plastic material (2)A...
Skin material (3)□A...Cushion material patent applicant Ikeda Bussan Co., Ltd.; t'1 mouth; l''2 figure 3 concave; 1'4

Claims (1)

[Claims] A skin material made of heat-softened thermoplastics is inserted into a mold, and then a foamable plastic material is injected into the mold and foamed to form a cushioning material. A method for manufacturing a cushion member, characterized in that it is made into a skin material by bulge molding.