Multi-pole circuit breaker

DETAILED DESCRIPTION We claim: 1.
The combination of a plurality of circuit breaker units, each unit having its own case containing; a pair of relatively movable contacts, an automatically resettable mechanism including a pivotable contact arm movable between open and closed positions, a tripping device including an armature pivotally movable toward and away from an electromagnetic coil or the like, said mechanism including a crank arm movable between "on" and "off" positions and a collapsible link with one end pivotally connected to said crank arm and its other end to said contact arm, latch means for preventing said link from collapsing, and means for disabling said latch means when said crank arm is moved "on" and said armature has been moved toward said coil, a common trip member of U-shape, with one leg of the "U" located adjacent one inside wall of the case and having a portion engageable with the associated resettable mechanism, the other leg of the U-shaped common trip member having a portion engageable with said means for disabling said latch means; at least two mating cases having abutting side walls assembled adjacent one another and having aligned openings defining a cavity, a common trip coupler located in said cavity and having opposing portions cooperating with portions of the U-shaped common trip members inside adjacent switch cases to cause pivotal movement of one of said members to move said coupler and in turn to effect pivotal movement of the trip member in the adjacent case.
2.
The combination defined by claim 1 wherein said common trip member one leg portion is engageable with said movable contact arm during said contact opening movement, and said other leg portion of said U-shaped common trip member being engageable by a projection on said latch disabling means to cause the said trip member to move and the contacts to open.
3.
The combination defined by claim 1 wherein each said tripping device includes an electromagnetic device including a fixed frame and said armature pivotally carried by the frame for initiating movement of said mechanism to the contact open position upon overload, said U-shaped common trip member also pivotally mounted to said frame