MANUFACTURE OF HOLLOW RESIN MOLDING

    公开(公告)号:JPS61202827A

    公开(公告)日:1986-09-08

    申请号:JP4388585

    申请日:1985-03-05

    Abstract: PURPOSE:To enable to discharge a core mold in a short period of time by contriving molding of a precise hollow product, by a method wherein a core made of resin inside of which is filled with substance such as sand or iron dust is inserted into a mold and the skin is molded on an external circumferential part of the core through injection molding. CONSTITUTION:An open part 3a at one side end of a core material 1 is closed with a plug 4a, a powdery filler 2 such as sand or iron dust is pressed in the inside of the core material 1 through an open part 3b at the other side end so as not to leave a gap behind, the end open part 3b is closed with a plug 4b and a core 5 made of resin is formed. Then the core 5 made of the resin is inserted into a cavity of a mold 6 for skin mold surface and the skin 8 based on injection molding is formed by fixing the core 5 by fitting parts 7a, 7b with the mold. As for the resin for the skin 8, thermoplastic resin such as nylon or polyester is appropriate and it is desirable to make the fusion point of the same is higher than that of the core material 1 and to make quality of the same identical with that of the core material. A hollow molded article is obtained by a method wherein cylindrical end parts 9a, 9b of a product material 9 is cut off along flange parts 10, 11 of the skin and the filler 2 in the inside of the core material 1 is pulled out.

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