METHOD AND MOLD FOR MOLDING FAN MADE OF SYNTHETIC RESIN

摘要

PROBLEM TO BE SOLVED: To provide the method and mold capable of producing a fan made of a synthetic resin reduced in the generation of a sink in its boss part and excellent in balance when mounted on a rotary shaft. SOLUTION: A heater 13 for heating a runner 12 and a valve 15 for opening and closing a gate 14 are provided to a mold 10 and the heating by the heater 13 and the supply of a resin by an injection molding machine are continued for a predetermined time after a thermoplastic resin is pushed in a molding space 20 while the valve 15 is opened to hold the pressure in the molding space to predetermined pressure and, subsequently, the valve 15 is closed and the heating by the heater 13 is stopped and the mold 10 is opened to take out a fan.