| 摘要 |
PURPOSE:To provide a mold for blow-molding use which is of a double mold structure consisting of a thin wall thickness inner split mold for heating use and an outer split mold for cooling use, and can obtain a molded product, being capable of being cooled in a short time and having an excellent surface luster, at a short molding cycle even if it is molded at a high mold temperature. CONSTITUTION:A thin wall thickness inner split mold 5, formed of Al having a high heat conductivity, is mounted to an outer split mold 8 through an air layer 10 through a force of springs 6, the inner split mold 5 is heated to a given temperature by a heater, and the outer split mold 8 is cooled by a cooling water flowing through a water water aperture 7 to independently regulate its temperature. When a thermoplastic resin, i.e., PE, extruded as a parison 2 through a die 1 reaches the bottom of the split mold, the split mold is closed, the parison 2 is inflated by air forced into through an air blow-in pipe 3, which causes the inner split mold 5 to compress the springs 6 and make contact with the outer split mold 8. When the parison 2 contacts the inner split mold 5, a heating, almost simultaneously, is brought to an OFF state, the mold 5 is cooled by the outer split mold 8 rapidly, and this cools also a molded product in a short period of time to remove a blow-molded product. |
