| 摘要 |
<p>A flow limit valve for limiting the flow rate of a pressurized fluid includes a valve body with an interconnecting cavity of circular cross-section. Within the cavity is a piston (31) that slides within the cavity under force generated by a pressure differential across the piston (31) to a closed position in engagement with a seat (29) at the end of the cavity. A first encapsulated magnet (45) is carried within the valve body in a chamber located on the side of the seat (29) opposite the cavity. The first encapsulated magnet (45) can be moved in response to another magnet (75) outside the valve body to move a pin (110) which can extend through the seat (29) when the piston (31) is in a closed position to thereby move the piston (31) to an open position. The magnetic forces applied through the valve body affect internal valve operation via the pin (110) and thus avoid the danger of noxious fluids escaping through sliding seals or flexible membranes.</p> |
