PURPOSE: To mold a final molded piece with expected dimensions so as to eliminate correcting process of dimension of the molded piece by previously setting dimensions of an outer mold and a core mold to dimensions compressed by a dimension equivalent to an extension of the final molded piece based on the height of the molded piece.
CONSTITUTION: Heights of a core mold 1 and an outer mold are previously set to small compressed dimensions based on 10% and a large diameter W1, a small diameter W2, and each pitch are set to relatively small dimensions accordingly. In a cavity formed by the core mold 1 and the outer mold, a melting synthetic resin is injected to fill it with the resin for molding. In an air hole 4 passing through in the axial direction of the core mold 1, a high pressure air (about 3kg/cm2) is supplied from a large diameter section 2 to a small diameter section 3 in the direction of an arrow. Then, the small diameter section 3 is filled with the high pressure air, the air goes around in a gap between a molded piece 5 and the core mold 1, and the molded piece 5 is taken out at the small diameter section 3 by going over raised parts 6 of the core mold 1.
CHOKAI MASAYUKI
ONO HIROSHI
| JPS61262112A | 1986-11-20 | |||
| JPS5724027U | 1982-02-08 | |||
| JPS50115972U | 1975-09-22 |
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