| 摘要 |
PURPOSE:To increase the force at which an evacuating device attracts and holds tightly top and bottom casting molds in vacuum casting by making the pressure in the evacuating device in the stage of sucking a molten metal into the cavities of the casting molds larger than the pressure in the stage of conveying the casting molds after suction. CONSTITUTION:An evacuating device 7 is lowered down to the top surface of a sealing part 6 of a casting mold and a space part 8 is evacuated to attract and hold top and bottom casting molds 1, 2 and to move the molds to above a furnace 12. The device 7 is lowered to immerse the runners 4a-4c of the mold 2 into a molten metal 11. The pressure in the space part 8 of the device 7 is regulated to evacuate the inside of the part 8 and mold cavities 3a-3c, thereby sucking the molten metal 11. The pressure in the part 8 is reduced after a specified time to hold the molds 1, 2 sucked therein with the metal 11 with the strong attraction force. The molds 1, 2 in this state are moved to a knockout device by which the molds are opened to the atmosphere. The molds 1, 2 are conveyed to the knockout device without any trouble by the above-mentioned mechanism. |
