Injection mold for producing spool

摘要

An injection mold for molding a spool with flanges at both ends of a shaft such that the inner wall surfaces of the flanges are not flawed, and the dimension between the flange inner wall surfaces is uniform and thus the flange inner wall surfaces are free from distortion, and further the cooling time is short and hence the molding cycle can be shortened. Two mold members for molding the outer periphery of the shaft of the spool and the inner wall surfaces of the flanges are formed of a material having relatively low thermal conductivity. A pair of mold members for molding the outer wall surfaces of the flanges are formed of a material having relatively high thermal conductivity at least at portions thereof that mold the outer wall surfaces of the flanges.