METHOD AND DEVICE FOR ISOTROPIC PRESSURE-MOLDING

摘要

PURPOSE:To make the increasing and decreasing rate of the pressure in a high- pressure molding vessel freely controllable and maintaining easily the pressure in the vessel by suing a piston actuated by a screw shaft for pressurizing the pressure medium in the high-pressure molding vessel. CONSTITUTION:A metallic powder material to be molded is put into a suitable vessel 10 and is thereafter hermetically closed by a cap 20. The water in a tank 12 is supplied to the vessel 10 by the operation of a pump 11. The water fills the inside of the vessel 10 and fills the water chamber 19 of a pressurizing cylinder 1 through a pipeline 9. A selector valve 18 is closed upon stopping of the pump 11 and a worm 8 is driven to rotate a nut 5 via a worm wheel 7 thereby advancing a screw shaft 3 and a piston 2 and pressurizing the water in the water chamber 19. The pressure is transmitted through a conduit 9 to the vessel 10 so that the powder material to be molded in the vessel is subjected to isotropic pressure-molding by the water of the pressure medium thereby producing the molding having an intended shape. The pressure reduction in the vessel 10 is easily accomplished by a selector valve 16 to permit quick starting of the succeeding high-pressure molding operation.