PURPOSE: To always supply a certain quantity of molten metal into an injection sleeve and obtain a cast product having stable quality by measuring the pressures in a molten metal supplying furnace and in a die cavity at the time of supplying the molten metal and matching this pressure difference to the setting pressure.
CONSTITUTION: At the time of casting, the pressure in the molten metal supplying furnace 11 with a pressure gage 16 and the piessure in the die cavity 3 with a pressure gage 7 are measured, respectively, and this pressure difference is matched to the setting pressure by controlling the gas pressure from the gas original pressure 15 through the pressure of the molten metal supplying furnace 11, while the molten metal 21 in the molten metal supplying furnace 11 is supplied into the injection sleeve 4. At this time, molten metal supplying completion signal is transmitted to a casting machine side, and by shifting a plunger tip 5, a molten metal supplying port is closed. Thereafter, by further shifting the plunger tip 5, the molten metal is injected into the die cavity 3. Before starting the supply of molten metal, the pressure in the molten metal supplying furnace and the pressure in the die cavity are equal, and at the time of completing the supply of molten metal, the difference between the pressure in the molten metal supplying furnace and the pressure in the die cavity is matched to the setting pressure. By this method, the fixed quantity of the molten metal can be supplied into the injection sleeve 4.
OTSUKI FUMIKAZU
SASAKI HIROSHI
TAKAHARA KAZUKI
