| 摘要 |
PURPOSE:To control the rising/lowering of a pallet always with the correct number of count pulses by carrying out correction when an elongation with the lapse of time on a cable body is generated, by counting the number of pulses and controlling a rising/lowering means, having the number of pulses as learning value. CONSTITUTION:The number of pulses which are generated by the revolution of a disc 22 during the time from the turning-OFF of an upper limit position detector through the separation of a pallet 8 up to the turning-ON of a detector for the arrival on a floor is previously memorized as the learning value N. Further, the number of pulses which are generated from an arrival floor surface to the deceleration position at a prescribed height is previously set, and the value which is obtained by subtracting this number of pulses from the learning value N is memorized as the deceleration pulse value. A high speed descent signal is transmitted when the pallet lowers, and the counting of the number of pulses supplied from a pulse generator 25 is started, and when the set number of deceleration pulses is obtained, a low speed descent signal is transmitted. The pulse count value in the case where the arrival floor detector is turned ON is memorized as the new learning value N. Since the number of deceleration pulses can be changed successiveley according to the change of the learning value, the deceleration position of the pallet can be kept always constant. |
