| 摘要 |
PURPOSE:To prevent generation of lack of a thickness in a screw part formed on a protrusion of a molded product, by a method wherein a core for molding the screw part provided on the protrusion of the molded product is arranged within a mold and a device cutting off a part of a film facing on the core is provided prior to blow molding. CONSTITUTION:Needle members 41, 41 ara provided so as to be capable of going in or out toward the inside of a molding space of a mold from a front end face 31b of a core 31 for molding a screw part provided on a protrusion Wa of a molded product W. Therefore, a part of a film F facing on the core 31 can be cut off prior to blow molding and hindrance to expansion of a parison 2 with tension of the film F can be prevented at the time of the blow molding. Consequently, material resin can be extended sufficiently to a screw molding part 31a of the core 31 and generation of lack of a thickness in a screw part of the molded product W can be prevented. |
