ON/OFF VALVE FOR MOLTEN RESIN, AND OPENING/CLOSING DEVICE AND OPENING/CLOSING METHOD FOR MOLTEN RESIN FLOW CHANNEL

摘要

PROBLEM TO BE SOLVED: To provide an on/off valve and an opening/closing device which can solve a problem such as leakage of a molten resin caused by defective operation due to seizure and intrusion of a resin into a gap.SOLUTION: An on/off valve includes: a resin flow channel 2 for passing a thermoplastic molten resin through a valve main body 10; cooling means 3 for cooling and solidifying the molten resin through an inner wall 20 of the resin flow channel 2; and heating means 4 for heating and melting the resin solidified through the inner wall 20 of the resin flow channel 2. The heating means 4 is an electric heater for directly or indirectly heating the valve main body 10. The cooling means 3 is provided with a flow channel 30 for passing a coolant through the vicinity of the resin flow channel 2 of the valve main body 10.SELECTED DRAWING: Figure 1