Abstract: A molded case circuit breaker is taught with a housing base and a primary cover disposed on the housing base. The primary cover has a recess therein for an auxiliary module which is disposed in the recess. A secondary cover is disposed on the primary cover for covering the recess when the auxiliary module is disposed therein. A combination manual trip and secondary cover interlock is provided which is accessible from outside of the secondary cover for manually opening separable main contacts or for automatically opening separable main contacts when the secondary cover is removed. There is also provided on the back plane of the housing a single piece DIN rail attachment for securing the back plane to a DIN rail. There is provided an under voltage release mechanism for actuating the circuit breaker to trip on the occurrence of an under voltage condition of predetermined magnitude across the lines served by the circuit interrupter.

Abstract: An electrical circuit interrupter comprising a housing with an operating mechanism disposed therein and including first and second separable main contacts disposed within the housing is taught. There is an electrically conducting first contact support which has a shape which substantially doubles back upon itself and which has parallel, spaced apart first and second legs forming a central region. An electrically insulating support member is supplied which is disposed in the central region and has a substantial portion outboard of the central region in a disposition to shield a portion of the contact support member. It also has a portion which captures the first contact support member. In addition, magnetic plates are disposed within the central region for cooperating with other closed loop magnetic plates outside of the support member for providing a slot motor action for the movable contact. An arc runner is provided which is trapped between the support member and the contact support conductor.

Abstract: A molded case circuit breaker is taught with a housing base and a primary cover disposed on the housing base. The primary cover has a recess therein for an auxiliary module which is disposed in the recess. A secondary cover is disposed on the primary cover for covering the recess when the auxiliary module is disposed therein. A combination manual trip and secondary cover interlock is provided which is accessible from outside of the secondary cover for manually opening separable main contacts or for automatically opening separable main contacts when the secondary cover is removed. There is also provided on the back plane of the housing a single piece DIN rail attachment for securing the back plane to a DIN rail. There is provided an under voltage release mechanism for actuating the circuit breaker to trip on the occurrence of an under voltage condition of pre-determined magnitude across the lines served by the circuit interrupter.

Abstract: Insulative guide members secured to an end face of switching apparatus between power terminals route electrical leads from attachment devices mounted inside the molded housing of the switch which exit the housing above the power terminals down between the power terminals toward the rear face thereby providing physical separation and electrical isolation between these leads and the power terminals and conductors connected to them. The insulative guide members are secured to the molded housing by a tongue-and-groove connection. The insulative guide members also form interface barriers with increased, oversurface distance between adjacent power terminals and conductors which can be further increased by longitudinal ribs on the guide members. In another configuration, the guide members can be secured to the confronting end faces of adjacent switching apparatus to provide interface isolation and to route leads from auxiliary switches from adjacent a front face of the switches toward a rear face.

Abstract: A circuit breaker includes a housing having an opening; separable contacts disposed within the housing and moveable between a closed position and an open position; an operating mechanism having a trip position where the separable contacts are tripped open for moving the separable contacts between the closed and open positions; a trip mechanism cooperating with the operating mechanism for tripping the operating mechanism to the trip position; an electromagnetic mechanism cooperating with the trip mechanism for sensing a current flowing between the separable contacts and engaging the trip mechanism with an armature in response to a predetermined current flowing between the separable contacts; and a manual push-to-trip mechanism operatively associated with the opening of the housing and cooperating with the electromagnetic mechanism for engaging the armature thereof, in order to engage the trip mechanism, trip the operating mechanism to the trip position, and trip open the separable contacts.

Abstract: A circuit breaker has an electrically conductive blow open latch which forms part of the power circuit so that only short flexible shunts are needed between the latch and trip mechanism. Load current can be conducted from the contact arm to the electrically conductive latch solely through the interface between the latch and the blow open camming surface on the contact arm, and/or through additional short flexible shunts between the latch and the contact arm, preferably adjacent the pivot of the contact arm.

Abstract: A molded case circuit breaker is provided with a toggle assembly having upper toggle links secured to U-shaped members of a cradle assembly with a hardened pin. The pin is formed with annular grooves disposed intermediate the ends forming a center sleeve portion and stop surfaces at each end. The center sleeve portion is slightly longer than the width of the U-shaped member to provide spacing between the upper toggle links and the U-shaped members. The upper toggle links are formed with U-shaped slots disposed at one end which are received in the annular grooves. The U-shaped slots formed at the other end of the toggle links are offset from the longitudinal axis of the toggle links and receive the pin. The upper toggle links are assembled such the offset U-shaped grooves are disposed in opposite directions to help secure the the assembly together.

Abstract: A molded case circuit breaker is provided with rubber stop assemblies disposed between the contact assemblies adjacent the outside poles and the cover portion of the housing. The rubber stop assemblies are disposed such that they prevent the contact assemblies from damaging the cover. The stop assemblies include a dual purpose U-shaped bracket having two parallel sets of arms. One set of arms is provided with aligned apertures at the free ends for receiving a pin which defines a pivot point for the crossbar assembly. The other set of arms is also provided with aligned apertures at the free end for receiving a metal pin for carrying a cylindrical shock absorber assembly. The shock absorber assembly is mounted adjacent outside poles above the contact carrier but spaced away from the inside of the cover of the circuit breaker. Thus, when the contact arm is opened, it will stop against the shock absorber and not damage the circuit breaker cover.

Abstract: A circuit breaker with electrical disconnect means characterized by a solenoid operator for moving a handle of a circuit breaker between ON and OFF positions. The solenoid operator includes a movable electromagnet and a movable armature for actuating the handle, an interlock switch serially connected to the electromagnet and a manual operator for overriding the solenoid operator by opening a circuit through the interlock switch.

Abstract: A molded case circuit breaker includes a highly integrated operating mechanism having an over-center, trip-free, pivot transfer toggle mechanism for opening and closing a pair of electrical contacts in response to overload and short circuit or fault current conditions. The toggle mechanism includes a pair of stationary, spaced apart links and a pair of movable, spaced apart toggle links. Each of the movable links includes an integrally formed, first or initial pivot point formed along its surface for engagement with a surface of one of the stationary links. Each of the stationary links includes a second pivot point formed along its surface for engagement by a surface of one of the movable links. The movable links are sequentially pivotably movable during a trip operation of the circuit breaker initially about the first pivot points and subsequently about the second pivot points.

Abstract: A molded case circuit breaker includes a movable upper electrical contact member having an end portion with an arcuate cam surface formed thereon for engaging an exposed spherical surface of a spring-loaded ball that is disposed in a pocket provided in a rotatable cross-bar of the operating mechanism of the circuit breaker. A compression spring is also disposed in the pocket between the cross-bar and the ball to supply sufficient biasing force to the end portion of the movable upper electrical contact member to enable the upper electrical contact member to move in unison with the cross-bar during normal operation of the breaker. Upon the occurrence of a high level short circuit or fault current of sufficient magnitude, the upper electrical contact member rotates and the arcuate cam surface thereof moves against the exposed surface of the then stationary spring-loaded ball.

Abstract: A molded case circuit breaker includes a handle lock or locking mechanism for preventing unauthorized use of the circuit breaker. The locking mechanism includes a lock cover disposed over a manually engagable handle of the circuit breaker and a spring biased locking cylinder and spindle assembly disposed normally above the lock cover and movable along an elongated slot formed through the lock cover. The cylinder and spindle assembly is mechanically connected to the handle for movement in unison therewith. The elongated slot includes an enlarged locking portion that is located along the lock cover in a position corresponding to the OFF position of the handle and the OPEN position of the separable electrical contacts of the circuit breaker. An elongated cylinder of the cylinder and spindle assembly is receivable through the locking portion of the elongated slot and when retained therein prevents substantial movement of the handle from its OFF position.