Patent ID: 7655877

Claim:
An air circuit breaker having a stationary contactor connected to a circuit and a movable contactor movable to a closing position where the movable contactor comes in contact with the stationary contactor to conduct the circuit or to a trip position where the movable contactor is separated from the stationary contactor to block the circuit, comprising: a switching mechanism connected to the movable contactor to drive the movable contactor to move to the closing position or the trip position; an overcurrent trip relay configured to compare a conductive current reference value, which is predetermined to determine whether a fault current has been generated on the circuit, with a current value detected on the circuit, to determine whether a fault current has been generated, and to output an electric trip control signal when being determined the fault current has been generated; an actuator configured to provide a mechanical trigger signal so as to trip the switching mechanism according to the electric trip control signal from the overcurrent trip relay; a first link unit connected between the actuator and the switching mechanism and configured to transmit the mechanism trigger signal from the actuator to the switching mechanism; a mechanical trip indicating mechanism configured to mechanically indicate at a front surface of the air circuit breaker that the trip operation has been performed; and a driving force generator for a trip indication connected both to the actuator and to the mechanical trip indicating mechanism, and configured to drive the mechanical trip indicating mechanism to provide the indication of the trip operation in response to the mechanical trigger signal generated by the actuator.