| 摘要 |
<p>A valve assembly comprising a rigid mounting (14) and a valve member (15) located in an opening in the mounting wherein an annular part (16) of the mounting around the opening provides a first valve seat (21) on one side thereof and a second valve seat (22) on the other side; wherein the valve member (15) comprises a first head (23) joined to a second head (25) by a neck (17) which extends through the aperture; wherein the first head has a resilient flange (24) which resiliently engages the first valve seat (21) to form a first valve (12) and the second head has a resilient flange (26) which resiliently engages the second seat (22) to form a second valve (13); and wherein the flange (26) of the second head has an actuator formation (27) thereon which is movable to move at least part of this flange off the second seat whereby, in use, to allow fluid under pressure to flow past this flange into the opening for automatically lifting the flange of the first head off the first seat when the fluid pressure in the opening is greater than the fluid pressure at said one side of the mounting.</p> |
