| 摘要 |
PURPOSE:To prevent the outflow of a molten metal from a venting passage irrespectively of the inflow speed of the molten metal by installing a molten metal contact detector in the valve head of a stop valve provided in the venting passage and making the valve openable and closable in accordance with the output therefrom. CONSTITUTION:When a molten metal is charged into the cavity of a die 40, a part of the molten metal infilters the inside of a venting passage 42 communicating with the cavity. A part of the molten metal contacts with the valve head 54 of a stop valve 52 in this stage, then a molten metal contact detector 70 provided in the head part detects the state thereof and outputs a detection signal. The supply of the pressure fluid to a fluid pressure chamber 60 is controlled in accordance with the output and the valve 52 is moved via a piston 58 housed in the chamber 60 is moved, whereby a venting port 48 is closed. The passage 42 and by-pass passages 44, 46 are shut off from the outside, by which the outflow of the molten metal is prevented. |
