| 摘要 |
A two-threshold pressure switch, for example for providing an early warning and an alarm condition concerning oil pressure in a hydraulic circuit for lubricating or braking a vehicle, comprises an insulating housing (1) bearing contact blades (spade-type blades 5 and 6), and receiving a moving member (14) driven by a pressure-sensitive membrane (12) and supporting contact members (16, 17) for making selective contact with a fixed conductive cup (10). In accordance with the invention, said fixed cap closes a cavity (9) in said insulating housing (1) in such a manner that said moving member (14), said contact members (16, 17), and resilient contact member holding means (22, 23) are all located on the same side of the cap (10). Said moving member (14) is in the form of a sleeve having a first one of said contact members (16) slidably mounted on its outside and having a second one of said contact members (17) slidably mounted on its inside. Different outside and inside abutments (27, 15 ) are associated with respective ones of said contact members to provide two different pressure thresholds for said switch.
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