PRODUCTION OF CHECK VALVE

摘要

PURPOSE:To accurately form an outflow port when a check valve is formed of a soft elastic material such as rubber. CONSTITUTION:The vulcanization molding of a check valve 1 is performed using an outer mold 7, a lower mold 8 and a middle mold 11. A thick-walled part is provided to the scheduled part of the outflow port 6 of the molded article 18 obtained by this molding. The middle mold 11 is extracted in such a state that the molded article 18 is left in the outer mold 7 and an underlay member is abutted to the rear surface of the thick-walled part 20 and a cutter is inserted in the molded article 18 to press the article 18 to form the outflow port 6 to the thick-walled part by the leading end of the cutter.