DEVICE FOR SUPPLYING MOLTEN METAL

PROBLEM TO BE SOLVED: To enable the supply of molten metal into an injection sleeve in a casting machine with one vacuum source, to reduce the cost and to reduce the entrapment of gas into the molten metal by communicating the vacuum source so as to be possible to reduce the pressure of the inner part of the injection sleeve. SOLUTION: A fixed quantity vessel 20 and the injection sleeve 24 in the die casting machine, are communicated with a molten supplying tube 22. The molten metal supplied into this injection sleeve 24 is filled up into a cavity 32 in a die 30 at high speed and high pressure by driving a plunger tip 26 in the injection sleeve 24 with a hydraulic cylinder 28 to cast a product. A passage 42 for reducing pressure passed through a vacuum pump 40 in the vacuum source, is communicated with the inner part of the injection sleeve 24. At the time of completing the feeding of the molten metal 52 into the fixed quantity vessel 20, the vacuum pump 40 is worked under condition of closing the valves 46, 48 to reduce the pressure in the inner part of the injection sleeve 24, and the molten metal 54, 56 is supplied into the injection sleeve 24.