| 摘要 |
PURPOSE:To reduce the pressure loss of an opening/closing valve during the rising operation of a hydraulic elevator and stop a car within a short distance even in the service interruption in the lowering operation. CONSTITUTION:When a car 2 rises, the first opening/closing valve 5 is closed, and the second opening/closing valve 21 is opened, and the pressurized oil discharged by a hydraulic pump 3 is sent into a hydraulic jack 1, and the car 2 is raised. In the lowering, the second opening/closing valve 21 is closed, and the first opening/closing valve 5 is opened, and the pressurized oil in the hydraulic jack 1 is discharged into an oil tank 8 by controlling the hydraulic pump 3. Since the first opening/closing valve 5 is exclusively used for lowering, the opening degree can be set small independently of the rising operation. Since the valve body 21b of the second opening/closing valve 21 has the opening degree corresponding to the flow rate of the pressurized oil, speedy closure can be realized when the flow of the pressurized oil is suspended because of the service interruption. |
