| 摘要 |
PURPOSE: To prevent the repetition of the oil temperature raising operation and the low-speed lifting operation for correcting the grounding level when such a trouble occurs that a car is lowered during the oil temperature raising operation of a hydraulic elevator. CONSTITUTION: When the oil temperature is decreased, a hydraulic pump 3 is operated to feed oil to an oil tank 8 through the third main circuit 20 and the third opening/closing valve 24 for the oil temperature raising operation. When the closing defect of the second opening/closing valve occurs during the oil temperature raising operation, the pressure oil of a hydraulic jack 1 flows through the second main circuit 18 → second opening/closing valve 19 →third main circuit 20 → third opening/closing valve 24 →oil tank 8, and a car 2 is lowered. When the descent of the car 2 occurs, the third opening/ closing valve 24 is closed to stop the car 2. |
