| 摘要 |
Provided is an opening and closing device for a hydraulic device which improves the convenience of use by automatically opening and closing a valve and enabling the manual opening and closing of the valve in a power failure; reduces damage to devices by preventing the overload of a pump by automatically discharging the oil to a tank when the pressure of oil flowing into a port exceeds a preset pressure; rapidly operate the valve by automatically draining the oil to the tank when the pressure of the oil inside the valve is increased due to a temperature rise ; and controls the opening and closing speed of a disk by controlling the flow rate of the oil supplied to the valve without the control of a motor. |
