Abstract: A sump pump switch has a swingable insulating yoke carrying flexible contact strips which are pivotally connected to the yoke for relative lateral movement. The movable contacts swingably engage in notches in electric terminal members. Over-center mechanism moves the yoke and contact strips between two positions, in one of which the movable contacts engage fixed contacts. Such engagement, and disengagement, is maintained by the flexibility of the movable contact strip, in the area of dead center position of the over-center mechanism and the resiliency of the contact strips absorbs energy on switch closing movement.

Abstract: A circuit breaker includes a recessed zone in the breaker housing for accommodating the bus clip of a mating circuit breaker when the breakers are mounted adjacent one to another on a panelboard. An arcuate groove of varying depths formed in the breaker housing communicates at its lower end with the recessed zone to permit the bus clip of the mating breaker to be moved from the recessed zone and along the arcuate groove, such that the mating breaker can be readily removed from, or installed into, the panelboard.

Abstract: An arcing contact for a high current capacity switch having a pair of switch members in sliding face-to-face engagement is formed from a set of resilient laminations that shunt the switch members as the switch makes on closing or breaks on opening. One end of the set of laminations is mounted on a face of one of the switch members, usually a blade, and the other end of the set of laminations is angled so that the end surfaces or tips bear against a face of the other switch member, usually a termination, when the arcing contact shunts the switch members. While in this position, a deflection of the laminations develops a spring force that urges the tips of the laminations into contact with the termination. The tips are inwardly bevelled with respect to the face of the termination and lie in a common plane so that during electrical connection they are in a substantially parallel relationship with the face of the termination, at substantially the same pressure.

Abstract: An arcing contact for a high current capacity switch having a pair of switch members in sliding face-to-face engagement is formed from a set of resilient laminations that shunt the switch members as the switch makes on closing or breaks on opening. One end of the set of laminations is mounted on a face of one of the switch members, usually a blade, and the other end of the set of laminations is angled so that the end surfaces or tips bear against a face of the other switch member, usually a termination, when the arcing contact shunts the switch members. While in this position, a deflection of the laminations develops a spring force that urges the tips of the laminations into contact with the termination. The tips are inwardly bevelled with respect to the face of the termination and lie in a common plane so that during electrical connection they are in a substantially parallel relationship with the face of the termination, at substantially the same pressure.

Abstract: An electric switch of the sort capable of carrying high amperage currents, especially under short circuit conditions is provided with a ferromagnetic U-shaped yoke piece around the contacts and an armature mounted on the movable contact carrier in position to be attracted by the magnetic force created in the yoke when current flows through the contacts. The fixed and movable contact members act like a one-turn electromagnetic coil especially under severe short circuit conditions to hold the contacts together against electromagnetic forces which otherwise would cause contact separation under such conditions. Rocking of the movable contact on the fixed contact is prevented by a leaf spring which acts in closed circuit position of the contacts and in cooperation with the holding means on short circuit conditions.