| 摘要 |
PURPOSE:To form a hollow part having a necessary size at a necessary position in the molding of a large blow injection molded product having a change in its wall thickness and an asymmetric shape. CONSTITUTION:After a molten resin is injected in a mold cavity 2, a pressure introducing period and introducing pressure are controlled corresponding to the pressure of the molten resin at an injection position to inject a pressure fluid in the cavity from a plurality of pressure fluid introducing ports 9a, 9b. Since the pressure irregularity of the pressure fluid caused by the non-uniformity of the pressure of the molten resin in the mold cavity 2 can be prevented, a hollow part having a necessary size can be formed even to a large blow injection molded product having a change in its wall thickness and an asymmetric shape at a necessary position. |
