| 摘要 |
A valve assembly is disclosed in which a main valve comprising a piston 13 controls the flow of gas from an inlet 4 to an outlet 9. An auxiliary valve, comprising a bore 28 and membrane 24, which can block the bore 28 controls the pressure in a first chamber 19, and by means of this controls the position of the piston 13. The auxiliary valve is actuated by the pressure in the outlet 9 acting on the membrane 24, such that, when the bore 28 is not obstructed by the membrane 24, the first chamber can be vented to atmosphere via the bore 28, a second chamber 26 partially defined by the membrane 24, and a duct 29. <IMAGE> |
