| 摘要 |
PURPOSE:To perform the supply and suction of air by a simple mechanism and to reduce manufacturing cost/running cost by interposing the inflow and outflow passages of an aspirator between pressure flow passages. CONSTITUTION:A parison 6 is extruded from a molding machine and arranged between left and right split molds 2, 3. The molds 2, 3 are clamped and the air from a pressure source is allowed to flow in a pressure flow passage 7. At this time, the air successively passes through the inflow and outflow passages 14, 15 of an aspirator 13, a pressure flow passage 8, a change-over valve 17 and the air blow-in port of a mandrel 5 to be supplied into the parison 6 to expand the parison 6 along the inner peripheral surface of a cavity 1a. Since a suction flow passage 11 sucking air on the side of the molding surface 2a for the cavity is connected to a suction flow passage 16 when the air passes through the aspirator 13, the parison 6 is sucked to the inner peripheral surface of the cavity la to be shaped and molded into a predetermined shape. When the parison 6 is brought into contact with the inner peripheral surface of the cavity 1a under pressure during molding and the pressure in the parison 6 rises, the change-over valve 17 is automatically operated to escape the air supplied into the parison 6 to a branched flow passage. |
