| 摘要 |
PURPOSE:To fill only the clean molten metal into a cavity and to obtain a product having a high grade by filling a molten metal into the cavity from under the molten metal surface of an injection cylinder and discharging the stagnating gas from the upper part of the cylinder to the outside. CONSTITUTION:The molten metal 4 which is poured into the injection cylinder 1 and has heavy specific gravity is admitted through a sprue runner 9 communicating with the bottom part of the cylinder and a gage 10 into the cavity 8 when a piston 3 advances. The oxide and combustion gas, etc. having the light specific gravity stagnate in a gas layer 5 in the upper part of the molten metal in the cylinder and the greater part thereof is discharged to the outside of the die through an air vent 13. The flow of such gases into the cavity 8 is obviated even if the extremely slight amt. thereof may remain in the runner 9. |
