Abstract: The operating mechanism of the four-pole circuit breaker comprises an auxiliary mechanism coupled to the main mechanism. The spring of the auxiliary mechanism exerts a torque on the bar, opposing the force of the contact springs when the circuit breaker completes its closing travel and when it is closed; the spring ceases to act on the bar when the circuit breaker has begun its opening travel and when it is open.

Abstract: An electrical breaking device including a movable contact assembly. The movable contact assembly includes a support cage and upper and lower contact fingers pivotally mounted thereto on respective upper and lower transverse spindles. The upper and lower contact fingers are parallel to each other and each include a head having a movable contact at a first end thereof, and a second end opposite the first end which is connected to a flexible conductor. The lower and upper contact fingers are cooperable with a stationary contact assembly. The lower transverse spindle is positioned to be closer to the first end of the lower contact finger than to its second end. In contrast, the upper transverse spindle is positioned to be closer to the second end of the upper contact finger than to its first end. The longitudinal spacing between the upper end contact spindles yield an attraction force which counter-balances repulsion forces acting on the movable contacts through which a current flows.