Molded case circuit breaker with removable arc chutes and disengageable transmission system between the operating mechanism and the poles

Claim 1

A multipole electrical circuit breaker comprising: a molded insulating case including an inner partition wall of insulating material, said case enclosing: an operating mechanism for activating said circuit breaker between open and closed positions; a plurality of poles located side-by-side with interposed insulating separation walls; each pole having a pair of separable contacts comprising a stationary contact cooperating in the closed position of the circuit breaker with a plurality of elementary movable contact fingers; a transverse rotatable switching bar common to all the poles and coupled to said operating mechanism for driving simultaneously the movable contact fingers of each pole between the open and closed positions; an arc chute for extinguishing an arc drawn in each pole between said movable contact fingers and the stationary contact in the open position; an insulating cage for supporting the movable contact fingers of each pole; a pair of first and second connection pads electrically connected respectively to the stationary contact and to the movable contact fingers of each pole; said cage and the second connection pad forming a sub-assembly which is securedly united to said partition wall of the case; a fixing device associated to said second connection pad for attachment of said sub-assembly to the partition wall; and a mechanical transmission link interconnecting the insulating cage with said switching bar by means of a disengageable coupling device which can be operated between a first retracted position for disengaging said link, and a second retaining position for establishing said link between the bar and the cage.