Abstract: A circuit interrupter includes a movable contact assembly having a movable contact, a stationary contact assembly, and an operating mechanism. The stationary contact assembly includes a conductor, a first stationary contact disposed on the conductor, and a second stationary contact disposed on the same such conductor proximate the first stationary contact. The first stationary contact has a first contact surface disposed a first distance from the conductor. The second stationary contact has a second contact surface disposed a second distance from the conductor. The second distance is smaller than the first distance. The operating mechanism is structured to move the movable contact assembly and cause the movable contact to engage or disengage from at least the first contact surface of the first stationary contact.

Abstract: A circuit interrupter includes a movable contact assembly having a movable contact, a stationary contact assembly, and an operating mechanism. The stationary contact assembly includes a conductor, a first stationary contact disposed on the conductor, and a second stationary contact disposed on the same such conductor proximate the first stationary contact. The first stationary contact has a first contact surface disposed a first distance from the conductor. The second stationary contact has a second contact surface disposed a second distance from the conductor. The second distance is smaller than the first distance. The operating mechanism is structured to move the movable contact assembly and cause the movable contact to engage or disengage from at least the first contact surface of the first stationary contact.

Abstract: A circuit breaker includes a circuit breaker frame and a trip unit. The circuit breaker frame includes a housing, a line terminal, a load terminal, separable contacts electrically connected between the line terminal and the load terminal, an operating mechanism structured to open and close the separable contacts, and a latch cooperating with the operating mechanism to open the separable contacts when actuated. The trip unit includes a housing, a line end terminal electrically connected to the load terminal of the circuit breaker frame, a load end terminal, and a fuse including a plunger. The fuse is housed by the housing of the trip unit and is electrically connected between the line end terminal and the load end terminal. An interface mechanism is structured to actuate the latch of the circuit breaker frame when the interface mechanism is engaged by the plunger of the fuse.

Abstract: A lockable fastener connects together a plurality of components of a circuit breaker and maintains electrical conductivity between the components while permitting relative movement therebetween. The lockable fastener includes a first clinch nut member and a second clinch bolt member. The clinch nut member includes a threaded cavity formed therein, a side having opening therein, and a passageway between the side at the opening and a surface proximate the threaded cavity. The clinch bolt member includes a threaded shank. At least a portion of the threaded shank is threadably receivable in the threaded cavity of the clinch nut member, in order to axially align the clinch nut and clinch bolt members. The clinch nut and clinch bolt members are adapted to be locked by deformation of the surface of the clinch nut member to prevent loosening of the members.

Abstract: A circuit breaker includes a housing including a primary cover and a secondary cover having a tab; separable contacts; and an operating mechanism adapted to open and close the separable contacts. The operating mechanism includes a cradle pivotally mounted within the housing, the cradle including a latch, and a latch mechanism within the housing. The latch mechanism is adapted to capture the latch of the cradle when the separable contacts are closed. The operating mechanism also includes a rotary interlock pivotally mounted within the housing and cooperating with the latch mechanism and the tab of the secondary cover to release the latch of the cradle and to trip open the separable contacts when the secondary cover is removed from the primary cover.

Abstract: A circuit breaker includes a housing and an operating mechanism having a cross bar supported by a first housing surface and moving in an arcuate path between open/tripped and closed positions, a pivotally mounted cradle including a latch, and pivotally mounted primary and secondary latches. The primary latch includes a pivot, an opening and a free end. The cradle latch rests within the opening when the contacts are not tripped open. The secondary latch includes a pivot and a surface. The latches are between a second housing surface and the cross bar in a first position. The cross bar is offset from the latches in a second position. The secondary latch surface and pivot are between the second housing surface and the primary latch pivot. The secondary latch surface engages the primary latch free end when the contacts are not tripped open and maintain the cradle latch within the opening.

Abstract: An improved lockable fastener that can be employed in a circuit breaker application includes a first member and a second member that are threadably cooperable with one another and a locking member that extends between the first and second members to resist loosening of the first and second members. The second member includes a threaded shank that is threadably received in a first threaded portion of a cavity formed in the first member. The locking member includes a threaded body and a taper, with the threaded body being threadably receivable in a second threaded portion of the first member, and with the taper being at least partially receivable in a receptacle formed in the shank of the second member. The receptacle defines a seat on the shank, and the taper engages the seat to deform at least a portion of the shank into engagement with a ledge that is interposed between the first and second threaded portions of the cavity.

Abstract: A baffle for use in a circuit breaker includes a first baffle mechanism and a second baffle mechanism. Each of the first and second baffle mechanisms includes a base, a plurality of elongated members supported by the base, and cross-pins or other elongated members for supporting the base of one of the baffle mechanisms substantially parallel to the base of the other baffle mechanism. The elongated members of the first and second baffle mechanisms are interleaved to form a labyrinth.

Abstract: A molded case circuit breaker having current limiting capabilities is dimensionally optimized for relatively smaller frame size circuit breakers. The handle yoke is supported with rollers thereby allowing the crossbar to be disposed in the space normally utilized for the handle yoke pivot axis. A clinch joint arcer assembly with a plurality of arcing contact arms, each pivotally connected by a clinch joint to a pivotally mounted main contact arm permits additional main contact arms to be provided in the same space normally occupied by the arcing contact arms alone. Additionally, arcing contact spring housings protect the arcing contact springs from deterioration due to corrosive ionizing gases generated during interruption. A positive off link assembly prevents the operating handle from being placed on an OFF position when the main contacts are welded together and transfers the force applied to the operating handle to the upper link to allow the weld to be broken.