METHOD FOR WELDING MOLDED PRODUCT MOLDED BY THERMOPLASTIC RESIN, AND ELECTRODE FOR WELDING USED FOR THE METHOD

摘要

PROBLEM TO BE SOLVED: To prevent a deformation of a resin of a resistance heater and a voltage applying part at the time of applying a voltage. SOLUTION: The method for welding a molded product molded by a thermoplastic resin comprises the steps of sandwiching a resistance heater 20 between welding surfaces of molded products molded by a thermoplastic resin, bringing an electrode 10 for welding into contact with the heater 20, applying a voltage to heat it, and spraying a cooling gas toward a voltage applying part 21 from a vent hole provided at the electrode 10 in the case of welding the moldings to suppress a heating temperature of the heater 20 at the part 21 to a melting temperature or lower of the resin.