Abstract: A circuit breaker includes a case, separable contacts having a fixed contact and a movable contact, and an operating mechanism for opening and closing the separable contacts. The operating mechanism includes a closed position, an open position, an operating handle for moving the operating mechanism between the open and closed positions, a movable contact arm carrying the movable contact, a linkage having a first end and a second end, and a snap lever. The second end of the linkage is pivotally mounted to the movable contact arm. The snap lever holds the linkage in the open position of the operating mechanism and releases the linkage as the operating handle moves from the open position toward the closed position of the operating mechanism, in order to snap close the separable contacts.

Abstract: A circuit breaker includes a case, a frame fixedly disposed within the case, separable contacts, and an operating mechanism for opening and closing the separable contacts. The frame includes a tab. The operating mechanism includes an operating handle, a closed position, an open position, a linkage, such as a pair of links, having a first end and a second end, and a link pivotally mounted to the case and to the first end of the linkage. The tab of the frame engages and stops movement of the link in the closed position.

Abstract: A circuit breaker includes a handle having OFF, ON and intermediate positions, and an extension. A blocking disk has a spring, and first, second and third surfaces. The handle and disk are co-pivotally mounted. The extension engages the third surface for rotation therewith. A pivot lever includes a first end adapted for engagement with a movable contact arm, and a second end adapted for engagement with the first and second surfaces. The first surface blocks the second end as the handle moves from OFF toward the intermediate position, and releases the second end to the second surface at the intermediate position. The first end blocks movement of the movable contact arm when the first surface blocks the second end, and releases the movable contact arm when the first surface releases the second end, thereby moving a movable contact toward a fixed contact in response to the bias of a spring.

Abstract: A circuit breaker includes a handle having OFF, ON and intermediate positions, and an extension. A blocking disk has a spring, and first, second and third surfaces. The handle and disk are co-pivotally mounted. The extension engages the third surface for rotation therewith. A pivot lever includes a first end adapted for engagement with a movable contact arm, and a second end adapted for engagement with the first and second surfaces. The first surface blocks the second end as the handle moves from OFF toward the intermediate position, and releases the second end to the second surface at the intermediate position. The first end blocks movement of the movable contact arm when the first surface blocks the second end, and releases the movable contact arm when the first surface releases the second end, thereby moving a movable contact toward a fixed contact in response to the bias of a spring.

Abstract: A circuit breaker includes a housing, line and load terminals, first and second circuit breaker mechanisms, an operating handle having on and off positions, and first and second links from the operating handle to the respective first and second operating mechanisms. Each of the circuit breaker mechanisms includes a set of separable contacts in series with the other separable contacts between the line and load terminals, an operating mechanism for moving the corresponding separable contacts between open and closed positions, and a trip mechanism cooperating with the corresponding operating mechanism for moving the corresponding separable contacts from the closed to the open position thereof. The first and second links engage the first and second operating mechanisms to move the first and second separable contacts, respectively, between the corresponding closed and open positions thereof responsive to the on and off positions, respectively, of the operating handle.

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 cover positioned on top of a base, the cover including first contact surfaces for contacting and mating with second contact surfaces of the base. The cover also includes a contact region. The operating mechanism includes a support member that is situated within the base and which has an upper surface with a raised region. The raised region is positioned to make contact with and pierce into the contact region before the first contact surfaces fully mate with the second contact surfaces.

Abstract: A circuit interrupter including a housing, separable main contacts within the housing, and an operating mechanism within the housing and interconnected with the separable main contacts. A trip mechanism is disposed within the housing that includes a trip bar assembly rotatable about an axis and that, when rotated, generates a tripping operation causing the operating mechanism to open the contacts. The trip bar assembly includes a trip member translatable along the axis. The trip mechanism includes a tripping actuator movable along a predetermined path of travel as a function of electrical current. The tripping actuator contacts a contact area of the trip member at a predetermined location along the predetermined path of travel of the tripping actuator and causes the trip bar assembly to rotate and generate the tripping operation upon a predetermined current threshold.

Abstract: A circuit interrupter including a housing including an abutment wall, separable main contacts within the housing, and an operating mechanism within the housing and interconnected with the contacts. A terminal is at least partially disposed within the housing. A locking plate is positionable between the terminal and the abutment wall for securing the terminal within the housing.

Abstract: A circuit interrupter including a housing including an abutment wall, separable main contacts within the housing, and an operating mechanism within the housing and interconnected with the contacts. A terminal is at least partially disposed within the housing. A locking plate is positionable between the terminal and the abutment wall for securing the terminal within the housing.

Abstract: A plunger assembly support structure for a molded case circuit breaker magnetic trip mechanism for aligning a trip mechanism plunger assembly. The plunger assembly support structure includes a base member assembly having a plurality of guide members, and a plunger carriage assembly slidably disposed adjacent to said base member assembly.

Abstract: A circuit interrupter including a housing, separable main contacts disposed in the housing, and an operating mechanism disposed in the housing and interconnected with the contacts. The operating mechanism includes a handle having a base into which is formed a channel. The base includes a compressible protrusion that is disposed within the channel. The operating mechanism further includes a handle assembly having a platform that inserts into the channel of the base. The platform includes an indent that mates with the protrusion.

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 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: A circuit interrupter including a housing, separable main contacts within the housing, and an operating mechanism within the housing and interconnected with the contacts. A trip mechanism is disposed within the housing and includes a rotatable trip bar assembly that, when selectively rotated, generates a tripping operation. The trip bar assembly includes an attaching structure which interconnects with an accessory trip member. The accessory trip member causes the trip bar assembly to rotate and generate a tripping operation when the accessory trip member is moved in a first direction. The accessory trip member is configured to enable flexing of the accessory trip member in a second direction opposite of the first direction.

Abstract: A molded case circuit breaker has paddles on the trip bar to utilize the arc gases generated during interruption to speed operation of the latchable operating mechanism and to protect the trip mechanism from debris in the arc gases. Alternatively, or in addition, lateral projections can be provided on the crossbar for similar purposes.

Abstract: A circuit interrupter including a housing, separable main contacts disposed in the housing, and an operating mechanism disposed in the housing and interconnected with the contacts. The operating mechanism includes a cradle for rotating from a first position to a second position in the event of a tripping operation. The cradle has an aperture with a smaller cutout portion and a larger cutout portion. The operating mechanism further includes a pivot pin disposed within the housing. The pivot pin is insertable through the larger cutout portion and is seated in the smaller cutout portion.

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: A circuit breaker handle is provided with a curved bearing surface at its pivot point. The handle bearing surface has a substantially constant radius and is connected to the body of the handle with a necked down handle extension. The handle extension has a width that is less than the width of the curved bearing surface at the point of connection between the bearing surface and the necked down region. The handle pivot mates with a corresponding bearing surface on a notch in the side plate that it pivots within. The arc of the curved bearing surface in the side plate is greater than that of the corresponding bearing surface on the handle and captures the handle pivot within the notch in the sideplate, so the handle cannot lift off the bearing surface on the notch as it is moved.

Abstract: A circuit breaker includes a housing, an operating mechanism and separable main contacts, and a rotatable crossbar which rotates to open and close the contacts. The crossbar interacts by way of a protrusion thereon with a rotatable, positive off-link. A handle mechanism is disposed in the housing and has a handle protruding from the housing which is normally movable from a closed to open disposition. However, if the operating mechanism has reacted in such a way as to open the separable main contacts but, in fact, they have not opened because, for example, they are welded shut, the protrusion on the crossbar will interact with the positive off-link and prevent the handle mechanism from moving to the opened position thus warning personnel that the contacts have not opened.