INJECTION-MOLDED DUCT

摘要

PROBLEM TO BE SOLVED: To improve the precision of the inside diameter of a duct end part in a duct having an undercut part when the duct is produced by injection molding. SOLUTION: An injection-molded duct 10 is formed by injection-molding a thermoplastic polyolefin elastomer in a cavity formed by a cavity mold for forming a duct outer surface 10A and a core mold for forming a duct inner surface 10B. The duct 10 has the bellows-shaped undercut part 12, and the connection opening end 10D (outside diameter size B) of the duct 10 in the opposite side end part 10C the extraction direction from a core mold C (arrow X direction in Fig. 1) is located inside the amplitude A of the undercut part 12.