PURPOSE: To efficiently and sufficiently vent gas and to improve the quality of a casting by arranging supplementary gas vent hole besides gas vent passage and executing gas vent in a cavity by working suction mechanism together with them.
CONSTITUTION: The cavity C in a mold M is formed by an upper mold 10, side molds 111, 112, lower mold 12, sand core 16, core print 16 and core bedding frame 18. This cavity C is communicated with an overflow part 20 connecting with the gas vent passage P at the upper part thereof and the runner 19 is shaped at the lower part thereof and the gas vent passage P is connected with the suction mechanism 26. Further, in roof face forming part 10a in the cavity in the mold M, plural hole parts 28 are formed and the gas vent pin 29 is arranged in each hole part. By this constitution, molten metal is poured into the cavity C and the gas vent is executed through each overflow part 20 and gas vent passage P. At the time of cutting off the gas exhaust passage P by filling up the molten metal into the overflow part 20, gas in the cavity C is vented from the gas vent hole arranging in the pin 29 in the hole part 28, and this gas vent hole is clogged by solidification following to invasion of the molten metal.
KAWASE AKIO
OHARA YUJI
MITSUO TAICHI
| JPS60250867A | 1985-12-11 |