INJECTION NOZZLE, INJECTION MOLDING DEVICE EQUIPPED WITH INJECTION NOZZLE, AND INJECTION MOLDING METHOD

摘要

PROBLEM TO BE SOLVED: To enhance the quality level of a molded product and increase the yield of a finished product by precisely controlling the temperature of a nozzle tip and upgrade the productivity beyond the conventional level by rapidly controlling the temperature of the nozzle tip. SOLUTION: A pore 21d is bored inwardly from the outer peripheral surface of a nozzle body 21 at the tip part of the nozzle body 21 and the inner end part of the pore 21d reaches a spot near the inner surface of a reversely tapered part 21c. A thermocouple is insetted in the pore 21d and a temperature-sensing part 23 of the thermocouple is arranged at the inner end part of the pore 21d. The temperature-sensing part 23 is arranged in a region A where the reversely tapered part 21c is provided as viewed in the axial direction of the nozzle body 21. At the tip of the nozzle body 21, a coolant introduction passage 21e which is opened in the outer peripheral surface of the nozzle body 21 is formed. This coolant introduction passage 21e communicates with a coolant passage 21f formed in an almost annular shape nearly encircling an injection channel 21a slightly to the tip side rather than the reversely tapered part 21c.