| 摘要 |
PURPOSE: To produce a structure into a desired size without using a mold having a size corresponding to that of the structure by partially taking out a formed structure while a part of the structure remaining in a mold is confined in the mold and molding the next part of the structure on the part remaining in the mold. CONSTITUTION: A plastic material containing a foaming agent is introduced into a molding cavity 20 to immediately start foaming. A movable part 18 is pushed forwardly and the foamed molten material is compressed by water pressure, oil pressure, air pressure or other means. When the molten material is coagulated, a mold is perfectly opened and a part 16 is perfectly detached from the part. This split mold assembly is constituted so as to extract the molded part of a roller door by the quantity just sufficient to leave the dragging end part of the molded part in the mold. The key 24 remaining in the mold after the separation of the mold is formed to each of the dragging ends 22 of the door molded in the mold. The key is formed by the restriction structure contoured in the rear end of the molding cavity 20. |
