CIRCUIT BREAKER

A circuit breaker is provided which is capable of effecting an instant cutoff when excess current is introduced while the circuit breaker is in operation. In addition, the circuit breaker has means cooperatively associated therewith for selectively indicating normal cutoffs and those arising because of excess current from the condition in which the contact members are engaged during normal operation. In this device, a movable arm rotatably disposed on a second rotatably mounted arm has a contact secured to one end which detachably contacts a fixed contact to switch a circuit. Means are provided for normally urging the first movable arm in a direction to separate the contacts. A driving device for displacing the first movable arm and the second movably arm jointly through an engaging mechanism connected therebetween causes the contacts to engage, and another device responsive to an excess current sensing means is provided for disengaging the engaging mechanism to permit the contacts to be separated in such cases, even while the circuit breaker is being normally operated.