| 摘要 |
PROBLEM TO BE SOLVED: To prevent solidifying of a molten resin before closing a gate hole by a valve pin by providing a heater at a lower end portion of a center pin. SOLUTION: A heater 14 is provided at an axial center of a lower end of a center pin 12. The heater 14 is constituted to be heated by supplying a current from a power source through a cord 16 for the heater connected through the pin 12. A current amount from the power source to the heater 14 is controlled by a controller, and a heating temperature of the heater 14 is regulated in response to a type of a resin, a type of a mold or a surrounding environment to mold a product. The heater 14 is controlled to be heated during a forwarding step of a valve pin 13 from a valve open state. Here, the lower end of the pin 12 is heated from the previous step of filling a molten resin in a product molding portion, and the heat is transferred to a fixed pin 20 brought into contact with the pin 12. Thus, the molten resin can be prevented from being cooled on the way and early solidified.
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