| 摘要 |
<p>A vacuum relief valve includes: a housing with a central cavity, the housing having a system branch, a vacuum branch, a pilot branch, and an exhaust branch, each of the branches in fluid communication with the central cavity and having a respective port; a piston assembly comprising a first disk located in the pilot branch, a second disk located adjacent the exhaust branch, and a connecting member to which the first and second disks are mounted; and an actuator attached to a pilot seal, the actuator configured to move the pilot seal between a closed position, in which the pilot seal is positioned in and seals the pilot port, and an open position, in which the pilot seal is spaced from and does not seal the pilot port. When the pilot seal is in the closed position, the second disk is positioned on and seals the exhaust port, and when the pilot seal is in the open position, the second disk is spaced from and does not seal the exhaust port In this configuration, often a smaller, less expensive actuator may be used to actuate the valve.</p> |
