Method of molding synthetic resin and apparatus for use therein

摘要

A molded article having a large undercut part is efficiently produced by a method of molding a synthetic resin with the use of an apparatus comprising an outer mold (S) and an inner mold (N) arranged so as to form a cavity (C) inside the outer mold (S), said inner mold (N) comprising a central mold segment having a part whose size is reduced toward its head and mold segments (6, 7) for forming an inner surface of a molded article which are supported so as to be able to meet and get apart from each other around the central mold segment (4) and divided into a plurality of separate segments, wherein said mold segments for forming the inner surface of the molded article are rendered movable toward the center of the apparatus by moving the central mold segment and wherein the inner mold (N) is withdrawn in the form of its size reduced as a whole from inside the molded article (21) supported in the outer mold (S).