| 摘要 |
A switch mechanism includes a fixed contact bar on which two or more contacts may be mounted. A movable contact is associated with each of the fixed contacts. Two independent toggle mechanisms are provided, each responsive to a different pressure-responsive displacement actuator for selectively actuating one or more of the movable contacts. In one embodiment having two normally open and one normally closed set of contacts, one toggle mechanism is connected by a sliding yoke to the movable contacts of one normally open set and the normally closed set, and the other toggle mechanism is connected by a second, independent sliding yoke to the movable contacts of the other normally open set and the normally closed set. Hence the normally closed contacts (which may be used to de-energize a compressor motor) are opened if either pressure limit is exceeded, but only the normally open set is disclosed which is associated with the tripped toggle mechanism. This may be used to indicate an alarm. Each toggle mechanism may be automatically resetting or require manual reset.
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