Patent ID: 7186941

Claim:
An arc extinguisher assembly for a molded case circuit breaker provided with an electrically insulated case, a fixed contactor and a movable contactor in the case, the assembly comprising: a plurality of plates made of a ferro magnetic material, each having a recess portion that allows a movement of the movable contactor, laminated to surround contacts of the movable contactor and the fixed contactor and installed in the case, to drive an arc when the arc is generated between the fixed contactor and the movable contactor; and a pair of plate support plates including outer wall portions to support the plates and inner wall portions provided adjacent to contacts of the movable contactor and the fixed contactor to compress an arc to be narrow, the plate support plates being installed to have a U-shaped horizontal section opened towards an opposite side of the contacts, wherein the outer wall portions of the plate support plates include connection holes formed therein, a guiding protrusion portion that guides a portion of a plate that is inserted in a connection hole being provided directly under each connection hole.