Abstract: A circuit breaker for a multi-pole electrical distribution circuit includes a cassette associated with each pole in the multi-pole electrical distribution circuit. Each cassette includes a housing, a pair of electrical contacts disposed in the housing, and a thermal and magnetic trip unit supported by the housing. The housing includes a first compartment having the electrical contacts disposed therein and a second compartment having at least a portion of the thermal and magnetic trip unit disposed therein. A wall separates the first and second compartments for isolating the second compartment from gasses generated by separation of the first and second contacts. A duct adjacent to the second compartment allows the gasses to pass to an exterior portion of the housing. The housing includes a pair of opposing slots formed therein for receiving edges of a load terminal.

Abstract: This concerns a molded case circuit breaker having separable main contacts and an operating mechanism utilized to cause the separable main contacts to open and close. A trip unit is provided to actuate the operating mechanism in desirable circumstances. The trip unit has a magnetic trip level adjustment dial, which has an adjustment face with a series of detents therein. The dial has a cam service, which interacts with internal portions of the trip unit to set or calibrate the level at which a magnetic trip actuation occurs. The aforementioned detent interacts with a spring loaded L-shaped member which fits into the casing of the trip unit along with the dial as a single unit.

Abstract: An assembly for interacting with a circuit breaker operating mechanism of a circuit breaker including a housing and a pair of contacts within the housing, the operating mechanism arranged to separate the pair of contacts upon the occurrence of a trip event is disclosed.

Abstract: An apparatus for operating a circuit breaker. The circuit breaker includes a housing, a cradle mounted in the housing and coupled to a handle and to a movable contact. The apparatus comprises a latch frame mounted in the circuit breaker housing. A latch roller is mounted on the cradle. A latch member is configured to selectively engage the latch roller and the latch member is rotatably coupled to the latch frame. A latch shaft assembly is rotatably mounted in the latch frame and selectively engaged by the latch member. Upon rotation of the latch shaft assembly, the latch shaft assembly will disengage from the latch member and cause the movable contact to move.

Abstract: A circuit breaker includes a housing, separable contacts, an operating mechanism having a pivotally mounted operator handle for opening and closing the separable contacts, and a trip mechanism releasing the operating mechanism to move the operator handle to its tripped position. A micro-switch includes an actuator lever movable between an actuated position and a non-actuated position and adapted to engage a surface of the operator handle. The micro-switch also includes a normally open contact having a closed state corresponding to the actuated position and an open state corresponding to the non-actuated position. The operator handle surface engages and moves the actuator lever to the actuated position in only the ON position of the operator handle. The actuator lever is in the non-actuated position in the OFF position and the tripped position of the operator handle.

Abstract: An adjustable solenoid having an enclosure containing a winding through which a current is passed. The winding defines an area and a plunger is positioned at one end of the area with a mechanical biasing mechanism for providing a biasing force to the plunger, the mechanical biasing mechanism is secured to the plunger at one end and a support at the other end. A stator having a first threaded portion engaged within a threaded opening of the enclosure causes the stator to travel between a first position and a second position as a rotational force is applied to the stator.

Abstract: A circuit breaker (10, 12) includes a sensing circuit (48, 50, 52), a control circuit (46), an actuator (42), an operating mechanism, and an interlock mechanism (70, 94). The sensing circuit (48, 50, 52) is configured to generate the sense signal representative of a power signal flowing through a power circuit (54, 56, 58). The control circuit (46) has a frame (74, 76) and is configured to receive the sense signal and to provide a trip signal on a first terminal (68). The actuator (42) is external to the control circuit frame (74, 76) and has a second terminal (98) coupleable to the first terminal (68). The actuator (42) is configured to receive the trip signal on the second terminal (98). The operating mechanism is coupled to the actuator (42) and is configured to open and close the power circuit in response to actuation of a lever (36). The actuator (42) is configured to actuate the lever (36), in response to the trip signal.

Abstract: A circuit breaker includes a movable contact, a fixed contact, a switching device, a switching operation handle, and an over-current tripping device. The switching device has a switching lever connected to the handle, a toggle linkage having an upper link and a lower link for connecting to the movable contact, a tripping mechanism for activating the toggle linkage in response to over-current, and an operation spring tightly stretched between the switching lever and the toggle linkage. A locking member is provided in the switching device for interconnecting the toggle linkage and the switching lever and for restricting a movement range of the switching lever according to an operational position of the toggle linkage. When main-circuit contact points are stuck, the locking member restricts the movement of the switching lever and prevents the handle from moving to the OFF position.

Abstract: A circuit breaker includes a housing; separable contacts mounted in the housing; and an operating mechanism for opening and closing the separable contacts. An overcurrent assembly is responsive to selected conditions of current flowing through the separable contacts and actuates the operating mechanism to trip open the separable contacts. A bonnet forms a U-shape which surrounds the separable contacts and which cools and splits an arc when the operating mechanism trips open the separable contacts. A first bonnet piece forms a first leg of the bonnet, and a second bonnet piece forms a second leg and a base of the bonnet.

Abstract: An operating mechanism controls and trips a separable contact structure arranged in a protected circuit. The mechanism includes a frame, a drive member pivotally coupled to the frame, a spring pivotally connecting the drive member to a drive connector, an upper link pivotally seated on the drive connector, a lower link member pivotally coupled to the drive connector, a crank member pivotally coupled to the lower link member for interfacing the separable contact structure, and a cradle member pivotally secured to the frame and pivotally securing the upper link. The cradle member is configured for being releasably engaged by a latch assembly, which is displaced upon occurrence of a predetermined condition in the circuit such as a trip condition. The mechanism is movable between a tripped position, a reset position, an off position, and an on position. Spacers are operatively positioned between movable members, and protrusions are operatively formed on the enclosure of the contact structure.

Abstract: A circuit breaker includes a housing, separable contacts disposed in the housing, a latchable operating mechanism structured to separate the separable contacts, and a magnetic trip mechanism coupled to the latchable operating mechanism. The magnetic trip mechanism includes a plunger assembly support structure and a plunger assembly having a moveable core. The plunger assembly support structure includes a wall having a slot therein. The moveable core rests in the slot. A positioning member has a hook and an opening. The hook engages the wall of the plunger assembly support structure. The moveable core passes through the opening of the positioning member, which retains the moveable core relative to the plunger assembly support structure.

Abstract: An electromagnetic relay (2) includes noise dampening means (20/32/34), such as an elastomeric insert, a noise dampening composition or mataerial, or a resin located at the juncture between the relay armature (4) and the spring (6), which noise dampening means (20/32/34) reduces noise generated by contact between the armature (4) and the spring (6) as the relay (2) is energized and the armature (4) is pulled into the core (8) and when the relay (2) is de-energized and the spring (6) biases the armature (4) away from the core (8).

Abstract: An adjustable magnetic trip unit for a circuit breaker includes a torsion spring which applies a bias force to the plunger of a trip solenoid. The torsion spring is mounted on a driven bevel gear and wound by an adjustment knob coupled to a driving bevel gear to adjust the current at which the solenoid is activated. An indexer having peripheral flats which engage a seat in the circuit breaker housing provides a plurality of discrete positions of the adjustment knob. Depressing the adjustment knob against a second spring unseats the indexer for rotation of the adjustment knob between settings. In addition, a slide with an inclined surface bearing against the plunger and coupled to the driven bevel gear, provides simultaneous adjustment of plunger gap with adjustment of the torsion spring force to increase the range of adjustment.

Abstract: The present invention provides a wire lug arc vent barrier for protecting a wire lug in a molded case circuit breaker, with the circuit breaker having a housing with a terminal for a load connection and a terminal for a line connection. The wire lug/arc vent barrier comprises a body having a first end including a tang, a second end including an elongated finger and a middle portion between the first end and the second end defining a concave space, with an opening at each of the middle portion, wherein the body is mounted in the housing.

Abstract: A magnetic trip unit for actuating a latching mechanism to trip a circuit breaker upon an overcurrent condition, the magnetic trip unit includes: a flux return component in electromagnetic communication with an electrically conductive strap; a tube disposed within the flux return component; a stator disposed at a first end of the tube and connected to the flux return component, the stator having a stator surface at one end; and a plunger slidably extending from a second end of the tube, the plunger comprises a plunger surface at one end facing the stator surface, the plunger further includes another end adapted to operably interact with the latching mechanism, the plunger is biased to a predetermined gap position.

Abstract: A method and magnetic trip unit for actuating a latching mechanism to trip a circuit breaker upon an overcurrent condition, the magnetic trip unit including: a first electrically conductive strap configured to conduct an electrical current; a first magnet yoke disposed proximate to the first electrically conductive strap; and a first armature pivotally disposed proximate to the first magnetic yoke in operable communication with the latching mechanism; the first armature providing a magnetic path having a reluctance to magnetic flux; and the reluctance is adjusted to prevent saturation of the magnetic flux when the current through the strap is a first number times a rated current of the circuit breaker and the reluctance is adjusted to promote saturation of magnetic flux when the current through the strap is a second number times the rated current of the circuit breaker, wherein the first number is a number smaller than the second number.

Abstract: A circuit breaker for interrupting the flow of current upon the detection of excess current or temperature is provided that has a current conducting blade mounted on a blade cross bar, which has a blade biasing spring for urging the blade to a first pivotal position on the blade cross bar during the open, closed, and tripped operation of the breaker, and for latching the blade in a second pivotal position on the blade cross bar upon the occurrence of a blown-open action of the breaker. The spring is a torsion spring that is coiled around a spring mounting pin, having a first end leg extending outwardly and formed into a hook anchored in a hook accommodating opening, and having a second end leg extending outwardly and cantilevered in contact with a spring follower pin. The second end of this leg is bent away from the spring follower pin to reduce the spring force exerted between the blade cross bar and the blade upon the occurrence of a blow-open action of the circuit breaker.

Abstract: A circuit breaker operating mechanism for separating a pair of electrical contacts within an electrical circuit breaker includes a lower link operatively connected to one of the electrical contacts. An upper link includes first and second legs extending from a central portion. The first leg is pivotally secured to the lower link, and the second leg includes a cam surface formed thereon. A roller is in intimate contact with the cam surface, and the cam surface is configured such that movement of the upper link relative to the roller causes the upper link to pivot about the central portion. Pivoting of the upper link about the central portion moves the lower link causing the second contact to move away from the first contact. An operating spring is configured to provide a force for separating the electrical contacts when the operating mechanism is tripped. An operating handle includes a void disposed therein, and an end of the spring is secured to the operating handle within the void.

Abstract: A pressure sensitive trip mechanism for actuating a circuit breaker operating mechanism to trip a circuit breaker includes a trip lever and a trip bar. The trip lever is rotatable about a first pivot. The trip bar is positioned proximate the trip lever. The trip bar is arranged to rotate about a second pivot in response to a predetermined level of pressurized gas created by separation of the pair of electrical contacts, thereby urging the trip lever to unlatch the circuit breaker operating mechanism. The pressure sensitive trip mechanism provides for very fast tripping of the circuit breaker in the event of a short circuit condition or an overcurrent fault condition within any one on the circuit breaker poles. In a multi-pole circuit breaker, the present invention provides for protection against single-phasing.

Abstract: A pivot joint for a movable contact arm assembly and a circuit breaker having an operating mechanism coupled to a line terminal, a trip mechanism and a load terminal with the load terminal coupled to a pivot mounting member. The pivot joint comprises a recess in a first sidewall of the contact arm with the recess co-axial with a mounting hole in the contact arm. A second recess is provided in a second sidewall of the contact arm with the second recess co-axial with the second mounting hole in the contact arm. The first and second recesses are co-axial with each other. A shaped washer, configured to fit in each of the first and second recesses is provided and maintained in position by a mounting axle configured to engage each shaped washer, each mounting hole and the pivot mounting member. The contact arm is then free to pivot about the mounting axle. A spring, with the spring configured to engage both ends of the mounting axle urge the contact arm against each shaped washer thereby completing the pivot joint.

Abstract: In relation to a circuit breaker, a left-side accessory switch storage section and a right-side accessory switch storage section are provided in a breaker case 1. A contact point of an ancillary switch 7 provided in one of the accessory switch storage sections is opened or closed in conjunction with an output protrusion 6a formed on an open-close lever 6 of an open-close mechanism section 3 on the main unit. A contact point of an alarm switch 9 provided in the remaining accessory switch storage section is opened or closed in conjunction with an alarm output plate 8 which operates in association with tripping action of the breaker. The output protrusion 6a is caused to oppose an operation lever 7a of an ancillary switch which is formed into a symmetrical bifurcated shape and which is provided in the accessory switch storage section. The alarm output plate constitutes a pivotal lever coupled to a toggle shaft 3a of the open-close mechanism section.

Abstract: An operating mechanism for a circuit breaker is provided. The operating mechanism includes a holder assembly being positioned to receive a portion of an operating handle of the circuit breaker. The holder assembly is capable of movement between a first position and a second position wherein the first position corresponds to a closed position of the circuit breaker and the second position corresponds to an open position of the circuit breaker. The operating mechanism further includes a drive plate being movably mounted to a support structure of the operating mechanism. The drive plate is coupled to the holder assembly. The operating mechanism also includes an energy storage mechanism for assuming a plurality of states, each state having a prescribed amount of energy stored in the energy storage mechanism.

Abstract: A release unit for a circuit breaker is equipped with a magnet yoke and an armature collaborating with it for actuating a release device, in which case a nonmagnetic weight element that increases the inertia of the armature is applied to the armature.

Abstract: A mechanism for operating a plurality of circuit interruption mechanisms of a circuit breaker, the mechanism applies a uniform force to the circuit interruption mechanisms. The mechanism applies a force to an elongated member for manipulating the circuit interruption mechanisms. The mechanism applies a force to the elongated member at a first position and a second position, the first position and the second position being intermediate to a center of the elongated member and the plurality of circuit interruption mechanisms.

Abstract: A molded case circuit breaker incorporates vacuum switches operated by a toggle mechanism. Pole arms tied together by a cross bar are rotated simultaneously by the toggle mechanism. A drive link translates the rotational movement of each pole arm into linear movement of a driven member along the axis of the movable electrode of the associated vacuum switch. A coupling bracket has a base section secured to the movable electrode, longitudinal sections straddling the movable electrode axis and terminal sections extending inward toward the plane of rotation of the pole arm from the ends of the longitudinal sections. Coupling members extend from the driven member through slots in the terminal sections of the coupling bracket. Springs couple the free ends of the coupling members to the coupling bracket to open and close the vacuum switch with operation of the toggle mechanism.

Abstract: A pressure sensitive trip mechanism for actuating a circuit breaker operating mechanism to trip a circuit breaker includes a trip lever and a trip bar. The trip lever is rotatable about a first pivot. The trip bar is positioned proximate the trip lever. The trip bar is arranged to rotate about a second pivot in response to a predetermined level of pressurized gas created by separation of the pair of electrical contacts, thereby urging the trip lever to unlatch the circuit breaker operating mechanism. The pressure sensitive trip mechanism provides for very fast tripping of the circuit breaker in the event of a short circuit condition or an overcurrent fault condition within any one on the circuit breaker poles. In a multi-pole circuit breaker, the present invention provides for protection against single-phasing.

Abstract: A circuit breaker comprising a fixed contact; a moveable contact, which is moveable into and out of electrically conductive engagement with said fixed contact; a line terminal operatively coupling said fixed contact with a circuit to be protected by said circuit breaker; a middle terminal operatively coupling said moveable contact with said circuit to be protected, in series with said line terminal, said fixed contact and said moveable contact; and a load terminal in series with said middle terminal and operatively coupling said circuit breaker to a load, a trip mechanism responsive to at least a thermal trip element for causing the moveable contact to move out of engagement with the fixed contact in response to a given amount of thermal energy caused by current over time passing through a circuit breaker current path comprising said fixed contact, said movable contact, said line terminal, said middle terminal, said load terminal and said thermal trip element from a circuit to be protected, wherein at least o

Abstract: A circuit breaker (100) for use between a load and a power source, comprising at least two movable contacts (212/222) for electrical connection to the load and power source respectively, a movable contact holder (220) holding the first contact (222), a first spring (224) biassing the contact holder (220) to move, and an actuator (210) arranged to move the second contact (212) into contact with the first contact (222). A locking frame (230) is arranged to lock the contact holder (220) and in turn the first contact (222) at a specific position into the path of movement of the second contact (212), against the action of the spring (224), for contact by the second contact (212). The locking frame (230) is supported for pivotal movement between a first position locking the contact holder (220) in said specific position and a second position releasing the contact holder (220) from said specific position. A second spring (238) biasses the locking frame (230) towards the second position.

Abstract: A pivot joint for a movable contact arm assembly and a circuit breaker having an operating mechanism coupled to a line terminal, a trip mechanism and a load terminal with the load terminal coupled to a pivot mounting member. The pivot joint comprises a recess in a first sidewall of the contact arm with the recess co-axial with a mounting hole in the contact arm. A second recess is provided in a second sidewall of the contact arm with the second recess co-axial with the second mounting hole in the contact arm. The first and second recesses are co-axial with each other. A shaped washer, configured to fit in each of the first and second recesses is provided and maintained in position by a mounting axle configured to engage each shaped washer, each mounting hole and the pivot mounting member. The contact arm is then free to pivot about the mounting axle. A spring, with the spring configured to engage both ends of the mounting axle urge the contact arm against each shaped washer thereby completing the pivot joint.

Abstract: An auxiliary magnetic trip system for a circuit breaker, the auxiliary magnetic trip system includes a strap configured to conduct a first level of electrical current and a second level of electrical current; a u-shape collar with a first pole face, the u-shape collar disposed around the strap; a trip lever rotatably mounted on an axis; and a holdback system releasably coupled to the trip lever, wherein the holdback system prevents movement of the trip lever at the first level of electrical current and releases the trip lever at the second level of electrical current.

Abstract: A circuit breaker system has been provided for the controlled interruption of at least one circuit, with a mechanical breaker element and an adjustment device coupled to the breaker element, so that the mechanical breaker element can be placed in at least a first, second, and third position in order to selectively break or let pass neighboring circuits in the first, second, or third position. The breaker element is rotatably secured in a fastening device, connected with one foot. The interruption conditions are provided by a magnetic coil, which exerts power by way of a magnetic field on a permanent magnet, which is secured to the breaker element. In the simplest case the circuit breaker system has three conditions at its disposal, by which one of two circuits can be broken. When the coil is without power, one circuit is broken. The other circuit is broken by reversing the circuit direction.

Abstract: An auxiliary magnetic trip system for a circuit breaker, the auxiliary magnetic trip system includes a strap configured to conduct a first level of electrical current and a second level of electrical current; a u-shape collar with a first pole face, the u-shape collar disposed around the strap; a trip lever rotatably mounted on an axis; and a holdback system releasably coupled to the trip lever, wherein the holdback system prevents movement of the trip lever at the first level of electrical current and releases the trip lever at the second level of electrical current.

Abstract: A low-voltage circuit breaker has a contact arrangement, a drive mechanism for actuating the contact arrangement , and an actuating shaft, which is used for transmitting a drive force from the drive mechanism to the contact arrangement. A bearing device for the actuating shaft has at least one bearing body, which is connected to a pole component accommodating the contact arrangement. Thus a unit is formed, which can be tested independently of the other components of the circuit breaker. In the case of multipole circuit breakers, a common actuating shaft is used for all contact arrangements and pole components, which is mounted approximately in the center of the main bearing body and near the ends of the auxiliary bearing bodies.

Abstract: A shock-resistant solenoid assembly includes a trip solenoid and an inertia lock, the inertia lock being operable to resist unintended engagement of a core of the trip solenoid with a trip plunger of a trip unit of a circuit breaker. The core is movable along a tripping path between a retracted position and an extended position, with the core engaging the trip plunger in the extended position. The inertia lock includes an inertia member and a latch. In response to shock loading, the inertia member interposes the latch into the tripping path to engage the core and resist the core from operatively engaging the tripping plunger under inappropriate conditions. The Abstract shall not be used for interpreting the scope of the Claims.

Abstract: An electromagnet assembly 200 for a circuit breaker trip unit includes a yoke 222, an armature 218 mounted for movement with respect to the yoke, and a coil 224, mounted with respect to the yoke for generating a magnetic field when energized with electrical current. The yoke and armature have complimentary male and female edges defining a working air gap C therebetween. When the coil 224 is energized, the magnetic field pulls the armature 218 towards the yoke 222 at a beginning of a stroke of the armature reducing the working air gap until the armature is seated at the yoke at an end of the stroke of the armature.

Abstract: An operating mechanism for a circuit breaker comprises: an operating handle movable between on and off positions extending substantially up at a point between the on and off positions; a crank for controlling a contact arm of the circuit breaker to cause the contact arm to move between open and closed positions; mechanism spring connected between the operating handle and the crank, causing said crank to move when discharged and when the operating handle is moved between said on and off positions; a trip latch configured to restrain the mechanism spring from discharging unless moved; and means for moving the trip latch upon removal of an electronic trip unit.

Abstract: An under-voltage tripping device installed on a main body of a circuit breaker includes an electromagnetic under-voltage tripping mechanism; an early-operation auxiliary switch for switching a conductive path of an electromagnet of the electromagnetic under-voltage tripping mechanism in connection with a handle mechanism of the circuit breaker; and a unit case having two opposite ends and external connection terminals at the two opposite ends thereof. The unit case is shaped to fit an outward frame of the main body. The wiring circuits for the electromagnet and the early-operation auxiliary switch are separated from each other in the unit case. The early-operation auxiliary switch is connected between the external connection terminals of the unit case, and the electromagnet has leads emerging directly from the unit case and connected to an external wiring.

Abstract: A magnetic trip with a fixed magnetic circuit polarised by a permanent magnet. The magnetic circuit includes two preferably identical parallel wafers each defining a main branch and a deflection tab with the presence of a coil on each branch. At their ends opposite to the mobile pallet, the wafers have in cross-section an L shape. The insulation structure carrying the coils is formed of two half-shells tightly holding the wafers. The trip can be used in circuit breakers.

Abstract: An operating mechanism controls and trips a separable contact structure arranged in a protected circuit. The mechanism includes a frame, a drive member pivotally coupled to the frame, a spring pivotally connecting the drive member to a drive connector, an upper link pivotally seated on the drive connector, a lower link member pivotally coupled to the drive connector, a crank member pivotally coupled to the lower link member for interfacing the separable contact structure, and a cradle member pivotally secured to the frame and pivotally securing the upper link. The cradle member is configured for being releasably engaged by a latch assembly, which is displaced upon occurrence of a predetermined condition in the circuit such as a trip condition. The mechanism is movable between a tripped position, a reset position, an off position, and an on position. Spacers are operatively positioned between movable members, and protrusions are operatively formed on the enclosure of the contact structure.

Abstract: A return spring mechanism is arranged to operate with a circuit breaker operating mechanism during a trip condition. The circuit breaker operating mechanism is movable between a tripped position, a reset position, an off position and an on position. The return spring mechanism is attached to the exterior of the circuit breaker frame and includes a return spring with a fixed end attached to the frame. When the circuit breaker is tripped, the return spring mechanism operates to provide an additional force to the handle yoke. The additional force applied by the return spring is predetermined to position the handle yoke intermediate to the handle yoke positions when the circuit breaker is off and on. Thus, the movement of the handle yoke to the intermediate position provides clear indication that the circuit breaker is in the tripped condition.

Abstract: The invention provides a tripping device for a circuit breaker having contacts arranged in a housing, said contacts being separable by actuation of a tripping shaft of a shutoff device. An exhaust duct assigned to said contacts is constructed in said housing. A lever rotatably arranged on said housing is interactively connected to said tripping shaft, and has a barrier surface associated with said exhaust duct which as the result of a pressure surge in said exhaust duct deflects said lever to actuate said tripping shaft.

Abstract: A blocking apparatus for blocking a contact structure from closing in a circuit breaker is provided. The apparatus includes a link extending from the circuit breaker and connected to a movable contact arm. The contact structure, being operated by an operating mechanism, remains in a separated position even when the operating mechanism is in the “ON” position due to the connection with the link of the blocking apparatus. A release assembly releases the link when it is desired to close the movable contact arm.

Abstract: An instantaneous trip power transformer includes a high current main outer winding wound to have one or more turns, for providing the main breaker contact current path and for serving as the transformer primary winding for providing power to the breaker electronic components. The transformer includes a secondary winding configured to provide power to trip circuit electronic components. The secondary winding is wound in a substantially cylindrical shape and has a bore therethrough. The main outer winding is wound around an outer surface of the secondary winding. The secondary winding supplies power to the trip circuitry. A third, or trip, winding is located within the secondary winding bore, and is configured to trip the breaker under electronic control by the trip circuitry. The third winding is wound in a substantially cylindrical shape and is energized by the trip circuitry.

Abstract: The circuit breaker (10) including a molded housing (12) including a main breaker cover (20), a first terminal (18) and a second terminal (16) mounted in the casing with a contact (44) electrically coupled to the first terminal (18) and a movable contact (42) electrically coupled to the second terminal (16). It also includes an operating mechanism (40) having a pivoting member (13) movable between an ON position, an OFF position and a TRIPPED position, wherein the pivoting member (13) is coupled to the movable contact (42). An intermediate latching mechanism (52) is mounted in the housing (12) and coupled to the operating mechanism (40) is in selective operative contact with a trip unit having a trip bar (54). The trip unit is also coupled to the movable contact (42) and the second terminal (16). An accessory socket (22) formed in the main breaker cover (20), on either side of an opening for the pivoting member (13) is in communication with the housing (12).

Abstract: An adjustable magnetic trip device for a molded case circuit breaker is provided where the trip device includes a plunger and a stationary core as well as a plunger support structure with a movable plunger carriage. The position of the plunger assembly and carriage relative to the stationary core is determined by a cam assembly having a body with a plurality of sections, each section having a different radius. The plunger carriage is responsive to rotation of said cam assembly and may be adjusted by rotating the cam. The over-current condition for the trip device is a function of the distance between the plunger assembly and the stationary core. Accordingly, the over-current condition may be changed by rotating the cam. As each section of the cam has a constant radius, the over-current condition remains the same no matter where the carriage contacts a certain section of the cam.

Abstract: A trip bar assembly for actuating a latching mechanism to trip a circuit breaker is disclosed. In an exemplary embodiment of the invention, the trip bar assembly comprises a trip bar having an aperture and a calibration screw. The trip bar is configured to interact with the latching mechanism and the aperture has a predetermined length. The predetermined length of the calibration screw is less than said predetermined length of said aperture such that the calibration screw is encased within the aperture prior to calibration of the trip unit. The trip bar assembly increases the calibration yield of circuit breakers by locating the calibration screws during the calibrations process.

Abstract: A parallel pole magnetohydraulic circuit breaker (10), having a single trip element (271) and a pair of trip mechanisms (101, 102), achieving an increased current carrying capacity with reduced nuisance trips. The tip mechanisms (101, 102) are contained within separate housings (14, 16), with electrical connections (30, 40) and multipole trip mechanism (101, 102) communicating through apertures in the common wall (14′). Preferably, the armature (260) of the trip element (271) acts on a single trip mechanism (101, 102), which multiplies the available force to trigger a trip of the other tip mechanism.

Abstract: A circuit breaker which has an auxiliary coil fitted onto the primary bobbin adjacent the pole piece having a dielectric auxiliary bobbin and a dielectric bobbin housing encapsulating the auxiliary coil and forming an encapsulated auxiliary coil assembly. Both the dielectric auxiliary bobbin and the dielectric bobbin housing are comprised of a polymeric material, preferably a liquid-crystal polymer. Preferably, the liquid-crystal polymer is an aromatic liquid-crystal polyester which is reinforced with about 30% glass and has a nematic liquid-crystal structure. Furthermore, it is preferred for the dielectric strength of the liquid-crystal polymer to be about 32 KV/mm to about 35 KV/mm.

Abstract: In an air circuit breaker, the present invention provides an air circuit breaker including an interlock apparatus which is capable of controlling translocation accurately by preventing a deformation and a bent of a lead bar and minimizing a tolerance in production by constructing the lead bar as two separated bodies and including a guide means for guiding a movement of the lead bar.

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. A trip mechanism is disposed in the housing and has an automatic trip assembly that generates a tripping operation. The automatic trip assembly includes a magnetic yoke, an armature, and a plurality of abutment members. The magnetic yoke has pivot supports providing for a rotatable disposition of a head portion of the armature. The assembly also includes a biasing member having a first portion and a second portion, the first portion abutted against a selected one of the plurality of abutment members, the second portion abutted against the armature and applying a force to the armature in a direction to normally rotationally displace a bottom portion of the armature away from the magnetic yoke, wherein selecting a different one of the plurality of abutment members to be the selected one causes the force to vary.