| 摘要 |
PROBLEM TO BE SOLVED: To provide a molding method for a cylindrical hollow molded product with a bellows portion such as a boot for a constant velocity joint, which allows manufacturing the hollow molded product by which the flow nonuniformity of a resin in molding does not occur, good appearance can be obtained, deformation in demolding by high pressure air is reduced, dimensional accuracy and dimensional stability is good, and which can be recycled by injection molding in good productivity. SOLUTION: A molten thermoplastic resin is injected from one point of a top portion of a dome-shaped 40 arranged so as to project from one opening end of the hollow molded product molded in a molding space 30 to the out side in an axial direction of the molded product to fill the molding space with the molten thermoplastic resin, thereby the hollow molded product whose one end is closed is molded, a cavity mold 10 is opened, and the molded product is taken out by blowing the high pressure air to the inner face of the part which becomes the lid formed in the dome-shaped gate 40 portion of the hollow molded product outwardly fitted on the core mold 20 from the core mold 20 after molding. COPYRIGHT: (C)2007,JPO&INPIT |
