| 摘要 |
PURPOSE:To reduce the cost of a hydraulic device and to improve the responsiveness in controlling a sliding nozzle, by driving the nozzle by means of the single hydraulic cylinder incorporating a position detector and is mechanically connected to the sliding nozzle. CONSTITUTION:There is no deviation between the actually measured signal (a) for the melt level from a melt level detector 14 and a set signal (b) for said level while the melt level in a casting mold 10 coincides with the set value; therefore, a servocontrol amplifier 17, a servocontrol valve 18 and a hydraulic cylinder 13 maintain the present condition. When the melt level deviates from th set value, the amplifier 17 and the valve 18 initiate new operations with a D/A converter 16 according to the deviation thereof, thereby actuating the cylinder 13. A piston rod is moved forward or backward until the signal (d) from the position detector incorporated in the cylinder 13 coincides with a command signal (c), by which the movable plate 12b of a sliding nozzle 12 is slid and the melt level is reset to its set value. |
