A valve for quickly exhausting a working chamber such as for a press clutch and brake actuator. A cylindrical body has a bore open to the chamber and leading to a transverse vent passage. A poppet is slidable in said body between a closed position separating the chamber from the vent, and an open position. An annular chamber is formed between the poppet and body, and a unidirectional annular seal on the poppet permits rapid filling of this chamber. A restricted passage is provided for exhausting the chamber. The valve is closed by the pressure differential across the valve sealing area, plus a spring, and is opened by pressure on said seal.
Principle of action:
When the single outlet exhaust valve needs to discharge the gas in the pipeline, the air in the pipeline enters the body cavity under the pressure of water and discharges from the exhaust nozzle. Then the water in the pipeline fills the body cavity. Under the buoyancy of water, the float ball moves upward and blockages the exhaust nozzle to achieve self-sealing. The pipeline is in normal operation and in water. Under the action of pressure, air is continuously discharged into the upper part of the body cavity of the exhaust valve, forcing the float ball to descend and leave the original sealing position. In this case, air is discharged from the exhaust nozzle, and then the float ball returns to the original position to self-seal. Therefore, the exhaust valve is always open in normal work, and the float ball repeats the above motions. As a result, the air is continuously discharged. When the body cavity needs to be repaired or cleaned, the valve should be closed.