| 摘要 |
A valve for a gas, comprising a housing (1,2) provided with an inlet opening (3) and an outlet opening (4) and a movable valve member (5) which can bear against a valve seat (6) for the purpose of closing the valve, with a control chamber (25) being formed on the side of the movable valve member remote from the valve seat, which control chamber comprises the stroke volume of the valve and which is connected, via a throttle channel (10) , to the inlet opening, a vent passage (26) between the control chamber and the outlet opening, a control valve (28) that is capable of closing and opening the vent passage in a controlled manner so as to allow gas to escape from the control chamber to the outlet opening, such that the pressure on the part of the other side of the movable valve member, which is in open communication with the inlet opening, moves the movable valve member away from the valve seat and opens the valve, wherein the vent passage extends beyond the valve seat in the outlet opening in the open position of the valve member, with a non- return valve being provided in or near vent passage, which non-return valve is capable of closing the vent passage so as to prevent gas flowing from the outlet opening to the control chamber in said open position of the valve member. |
