| 摘要 |
PURPOSE:To facilitate production of hollow plastic articles by placing in main molds a core in which a heating wire is embedded, pouring a plastic material into the main molds, hardening the plastic, and then energizing the heating wire to melt and remove the core. CONSTITUTION:A heating wire 49 is embedded in the center of a melt core 51 formed of a low-melting alloy. After the core 51 is placed in a set of simplified main molds 40a, 40b, a plastic material 52 is poured thereinto through an inlet 41 and gradually hardened. The plastic material is preferably a thermosetting resin that slowly hardens, for example, an epoxy resin or urethane resin. When sufficiently hardened, the plastic article, for example, a valve casing 5, is taken out. By energizing the embedded heating wire 49, the low-melting alloy core 51 is melted and removed. The method thus enables production of hollow plastic articles in small quantities at a low costs. |
