METHOD OF MANUFACTURING DOUBLE-WALL BLOW MOLDING AND MOLDING OBTAINED THEREBY

PROBLEM TO BE SOLVED: To provide a double-wall blow molding consisting of an inner and an outer blow molding having an accurate shape. SOLUTION: An inner blow molding 1 having been blow-molded in advance is arranged between blow molding molds 24 and 25, a cylindrical parison 35 is caused to descend outside the inner blow molding 1, and the blow molding molds 24 and 25 are closed for clamping. In the clamping, a part of the parison 35 is pressed toward the inner blow molding 1 through a protrusion 31 formed on the inside surface of the cavity formed by the blow molding molds 24 and 25 so as to fuse the part of the parison with the inner blow molding 1, and another parts of the parison 35 are pressed toward the plate-shaped rib 4 formed on the inner blow molding 1 from both sides in the parting portion so as to fuse the rib 4 and the parison together, with the rib 4 held between the parison. Pressurized air is blown into between the parison 35 and the inner blow molding 1 and into the inner blow molding 1 to blow-mold the parison. COPYRIGHT: (C)2008,JPO&INPIT