Patent ID: 8242864

Claim:
A trip mechanism for a circuit breaker, provided with a stationary contactor, a movable contactor movable to an open circuit position separated from the stationary contactor and a closed circuit position contacted with the stationary contactor, and a switching mechanism configured to drive the movable contactor to the open circuit position or the closed circuit position, the trip mechanism comprising: a coil configured to generate a magnetic absorption force due to a fault current on a circuit; a stationary core fixed to a lower portion of the coil within the coil; a movable core movable down to the stationary core within the coil by the magnetic absorption force generated from the coil; and a trip lever rotatably connected to the movable core so as to be pulled by the movable core when the movable core is downwardly moved, and configured to trigger the switching mechanism such that the movable contactor is moved to the open circuit position, wherein the movable core comprises a pair of circular plate portions outwardly protruding from an upper end thereof in a radial direction and a neck portion formed between the pair of circular plate portions and said trip lever comprises hinge portions at both ends thereof and a channel portion engaged with the neck portion of the movable core, and wherein the trip lever further comprises a triggering protrusion extending from the channel portion and configured to push the switching mechanism for triggering the switching mechanism to trip.