| 摘要 |
<p>A temperature compensated differential fluid pressure switch (16) includes a housing (22) having a fluid inlet (18) and outlet (20), an actuatable differential fluid pressure sensor (24) for sensing differential fluid pressure across the inlet (18) and outlet (20), a wax motor (54) and poppet valve (62) for controlling fluid communication between the fluid inlet (18) and fluid outlet (20) to inhibit actuation of the differential fluid pressure sensor (24) in response to the fluid being below a temperature threshold, and a magnetic device (74, 76) for generating a signal respons ive to the differential fluid pressure. The temperature compensated differential pressure switch detects a plugged filter. Prior switches permit actuation of the differential pressure sensor during cold operating conditions and use a temperature sensor wich is not highly accurate. The present invention uses a temperature sensor or wax motor that inhibits actuation of the differential pressure sensor during such conditions and is accurate to within a small percentage of the threshold temperature.</p> |
