Switching mechanism for protective cct. breaker - has pivoted spring-loaded contact arm linked over latch to pivoted operating arm

摘要

The switching mechanism has its contact arm (5) pivoted at its centre on a pin and spring-loaded (7) at its upper part. In the ON position the lower end of the contact arm touches a lower fixed contact (11) and in the OFF position the upper end touches an upper fixed contact (8). The operating lever (1) is linked to a locking device (3) and from the locking device to the contact arm centre pin. The contact arm pin and the locking device pin (9) move along separate slots (10, 6) when the switch is operated. The locking device holds the contact arm in its ON position against the action of the spring. When the operating lever is released, i.e. pivoted to the right, the locking mechanism drops and the spring pulls the contact arm away from the lower contact.