| 摘要 |
<p>A pneumatic pilot valve comprises a valve body having an inlet, an outlet, a flow passage, and first and second valves arranged to control flow through the valve. The second valve includes a tapered valve seat opening into a cylindrical bore, and a thrust pin includes a tapered second part and an annular recess having a seal. The thrust pin is movable between a first position, a second position, and an intermediate position. The tapered second part of the thrust pin is arranged to engage the tapered valve seat to close the second valve when the thrust pin moves to the second position, and the resilient seal is sized to engage the cylindrical bore when the thrust pin is in the intermediate position.</p> |
