| 摘要 |
PURPOSE:To cause a molded object to be easily drawn out from a mold by cooling and shrinking the resin on an insert core and outer periphery, and by molding a clearance therebetween. CONSTITUTION:The metallic core 3 having been thermally expanded by preheating it to high temperature, is inserted into one body core 4 without a parting face. Resin material 2 is injected into between the core 4 and the metallic core 3. The inserted metallic core 3 and the resin 2 are shrunk by cooling, and a clearance is generated in between the resin material 2 and a mold. By using this clearance, the central shaft of the core 3 is driven with a projecting pin 5, and a molded object is drawn out from the mold while twisting said object. |
