Abstract: A circuit interrupter including separable main contacts, an operating mechanism interconnected with the contacts, and a housing in which the contacts and the operating mechanism are disposed. The housing includes a first attaching region and a mounting cutout. A shield is provided that includes a second attaching region attaching with the first attaching region for connecting the shield to the housing. The shield includes a tab adapted for covering the mounting cutout when the connection is made.

Abstract: A circuit interrupter including a housing, separable main contacts disposed in the housing and rotatable between a contact open position and a contact closed position, and an operating mechanism disposed in the housing and interconnected with the contacts for rotating the contacts alternatively between the contact open position and the contact closed position. The operating mechanism includes a handle moveable by an operator between handle open and handle closed positions normally corresponding to and resulting in the contact open position and the contact closed position, with the handle including a protrusion. The operating mechanism further includes a crossbar assembly for rotating with the contacts as the contacts rotate between the contact open position and the contact closed position.

Abstract: A circuit interrupter including an operating mechanism and separable main contacts interconnected with load and line terminals has an interface region between the top and bottom portions of the completed housing thereof, which may be of reduced cross section relative to the remainder of the side walls of the circuit interrupter for being moved or pushed outwardly under the pressure of expanding gas during a circuit interruption operation. To more easily clear or separate abutment surfaces by near lateral movement thereof to provide a small opening for pressurized gas to escape the elasticity of the side wall is utilized for this purpose. Provided that the elasticity limit is not exceeded, the wall will return to its original position sealing the internal portions of the circuit interrupter from the exterior once the gas pressure has dropped below a predetermined level.

Abstract: A circuit breaker has a shock absorber to prevent nuisance tripping which results from shock generated during ON to OFF operation of the circuit breaker. The shock is primarily caused by a snap action which occurs within the operating mechanism of the circuit breaker when the handle is moved from the ON to OFF position. The snap action results from the circuit breaker employing, as part of the operating mechanism, a toggle mechanism within an over center tension spring as a means for imparting motion in the operating mechanism. By strategically positioning the shock absorber for engagement with the operating mechanism when the circuit breaker is in the OFF position, the shock may be effectively absorbed thereby preventing the undesirable nuisance tripping.

Abstract: A circuit controller for selectively connecting a power source to a load includes a switching mechanism, which selectively connects the power source to the load and switches a current which flows through the switching mechanism, and a substantially radiant energy dissipating positive temperature coefficient current limiter for limiting the current which flows through the switching mechanism. The switching mechanism includes a current sensor, which senses the current flowing through the switching mechanism and provides a sensed current value, and a switching controller for disconnecting the power source from the load whenever the sensed current value is above a predetermined current value. The switching mechanism may include a contactor having separable contacts which are responsive to the switching controller. The current limiter may have a first resistance which results from a first series current, and a higher second resistance which results from a second series current.

Abstract: An improved trip device for operating a trip mechanism which, in turn, operates a circuit breaker mechanism for opening a set of electrical contacts. The trip device includes a spring-biased actuating rod which is mechanically operated by a solenoid. The actuating rod has a notched end which is secured by a rotatable shaft at a notch portion of the shaft. The shaft has latch arms, and the core of the solenoid has projections extending into slots in the latch arms. When the solenoid receives a faulty current signal, the core moves and causes the projections to forcibly impact against the latch arms which rotates the shaft, whereby the notch portion of the shaft aligns with the notched end of the actuating rod and the actuating rod reciprocally moves into the notched portion of the shaft thereby actuating the trip mechanism.