Automatic fluid pressure switching monitor - has pivoting lever inform of snap-action spring carrying moving contact

摘要

The monitor supervises the fluid pressure with respect to preset pressure value lower and upper limits. When the pressure limit is passed, a switching contact is operated. The monitor has a diaphragm dividing its housing into two separate, tightly sealed chambers. It operates against adjustable pressure of a spring pressing through a pin on a lever actuating the contact. The lever carries the moving contact, and is in the form of a snap-action contact spring (15) with two stable end positions between which it can only snap. The free end of the spring carries a contact rivet, round which it has a bishaped recess.