Nippon Steel Chemical Co., Ltd.

Shoichi Hamada

Hisanori Kato

Hiroshi Aida

An expansion injection molding die having a plate forming the die cavity, a backup plate, a core plate, ejector pins inserted through the backup plate and the core plate for separating the molded products from the die cavity, and a gas introducing passage communicating with the pressurized gas source for introducing gas into the die cavity. The plate that has holes through which the ejector pins are injected are formed with hollow portions. In each of the hollow portions, a guide ring is installed so that it is freely movable at least two-dimensionally. A sealing member is installed in an expanded hole portion in the guide ring so that it is in sliding contact with the ejector pin.

Growing community of inventors

Kawasaki, Japan

Shoichi Hamada