| 摘要 |
PURPOSE:To control precisely the immersion depth of the molten metal in a casting mold by attaching a suction head holding the casting mold to a lifting arm via a load cell, stopping the descent and evacuating the inside of the casting mold after the value obtd. by subtracting the output signal value of the load cell after the start of the descent from the output signal of the load cell before starting the descent attains a prescribed value. CONSTITUTION:A cylinder 12 descends and the signal of a level L1 is obtd. from the load cell 8 when the casting mold 3 is attached to the suction head 4 and a directional control valve 17 is changed over to the position on the right side. When the casting mold 3 contacts with the molten metal 2 and is immersed therein, the mold 3 receives the buoyancy and the signal of the cell 8 decreases like in the section C. Since the buoyancy is proportional to the immersion depth, the immersion depth at the time alpha can be regarded as the quantity proportional to L3 obtd. by subtracting the signal L2 from the signal L1 before the immersion. The mold 3 is thus held at the desired depth in the molten metal when the mold 3 is lowered to an stopped at the point where L3 attains a desired value. |
