CHECK VALVE FOR INJECTION MOLDING MACHINE

摘要

PROBLEM TO BE SOLVED: To reduce a frictional heat caused by a friction between a rear end of a screw head and an end face of a check ring at a front end side in the case of metering an injecting resin by decreasing a contact area therebetween without changing a size of a check valve of an injection molding machine. SOLUTION: The check valve 9d comprises a contact preventive step 14 provided so that a ratio of a contact area of rear ends 12 of four fins 4 for forming a front end of a screw head 5c with a front end face 11 of a check ring 7 at a front end 3 side to a sectional area of the substantially cylindrical check ring 7 falls within a range of 0.1 to 0.02, arranged at each rear end 12.