| 摘要 |
A deflation control valve that automatically varies the rate of air flow through said control valve to provide a constant but adjustable rate of change of pressure during the deflation or exhaust of gas held in a closed pressurisable vessel to which said valve is connectable comprising a valve body having a passage communicatable with said pressurisable vessel, said valve body defining a valve chamber communicating with said passage in which a flexible diaphragm is provided partially or substantially closing said valve chamber, said diaphragm being in sealing abutment with a seat in said valve housing around the periphery of said diaphragm, and forming on the opposing side a part of an exhaust chamber, said diaphragm, in use, being, on the valve chamber side subject to the gas pressure in said pressurisable vessel and, on the opposing side, subject to the gas pressure in the exhaust chamber, which may be atmospheric pressure, and said diaphragm having an aperture or port extending therethrough, and said diaphragm on one side being in communication with said valve chamber and, on the opposite side, being in communication with said exhaust chamber or atmosphere and being closeable or partially closeable by a displaceable closure disc, plate or platen which is releasably held in the closing position against said diaphragm and covering said port by an operable, controllable or adjustable release means, which by adjusting said release means to open and closed positions or intermediate positions, controls the rate at which gas flows through the valve, gas passing from the valve chamber through the port in the diaphragm and between the face of the closure disc and diaphragm to exhaust or atmosphere to allow the pressure of the pressure chamber to drop in a controlled manner.
|
