Abstract: Adjustment of the static position of the armature of a solenoid or relay-type structure is used to adjust the trip level. An armature stop rod extends through an opening in the structure and is bent over to adjust the length of the stop rod between the frams opening an the active part of the armature. A compact structure is achieved by winding the device coil on a plastic bobbin which provides a bearing for the armature at one end, and an extension through which the adjustment portion of the stop rod extends. This permits ready adjustment after assembly, even when the device spring is arranged around the armature inside the bobbin.

Abstract: A switch which is superior in current limiting performance. The switch comprises a movable contact element having a pair of movable contacts secured thereto, a pair of fixed contacts individually secured to fixed contact elements for individually contacting with the movable contacts, an electromagnetic driving device including a movable iron core, and a first operating rod secured to the movable iron core. An electromagnet is disposed alongside the electromagnetic driving device and includes a movable iron core, and movement of the movable iron core of the electromagnet is transmitted to the movable contact element by way of a transmitting member and a second operating rod. The first and second operating rods are disposed for movement along a common axial line, and movement of the movable iron core of the electromagnetic driving device is transmitted from the first operating rod to the movable contact element either directly or by way of the second operating rod.

Abstract: Field-installable accessories are used within a thermal-magnetic industrial-rated circuit breaker. One such accessory in the form of a combined undervoltage release and shunt trip unit is field-installable within the circuit breaker cover. A bell alarm accessory unit can also be inserted within the circuit breaker cover either in combination with or apart from the undervoltage-shunt trip accessory unit.

Abstract: A circuit breaker includes a compressive turning spring hung between a movable contact arm pivoted at an end to a handle rotatably mounted to a first reference position and a cradle pivotably mounted to a second reference position and disengageably locked to an abnormal current detection and trip mechanism. Under normal operation of the breaker, the turning spring exerts a contact pressure between movable and fixed contacts. Upon detection of an abnormal current, the turning spring is caused to turn so as to open the contacts. With this arrangement, the dispositions of constituent elements and their interlocking assembly can be simplified.

Abstract: A molded case circuit breaker of the type containing an electronic trip unit and a combined actuator-accessory unit to articulate the circuit breaker operating mechanism employs an optimum cradle configuration within the circuit breaker operating mechanism. The operating cradle is fabricated from a steel composition that is optimized to promote improved hardness properties. The optimized cradle interacts with the circuit breaker latch assembly to substantially reduce the tripping force required to articulate the operating mechanism.

Abstract: A molded case circuit interrupter of the type employing a thermal-magnetic trip unit to interrupt circuit current utilizes a flexible electrical braid conductor to connect between the thermal-magnetic trip unit and the movable contact arm. A helical spring arranged around the braid conductor at the welded connection with the movable contact arm provides long-term strain relief. A metal phosphate coating on the surface of the circuit breaker operating cradle and latch assembly eliminates polishing while insuring release of the cradle from the cradle-latch interface surfaces.

Abstract: An interrupter actuator comprising a frame, a pivot lever mounted on the frame for pivotal movement relative thereto about a first axis and between first and second positions, an operating lever mounted on the pivot lever for pivotal movement relative thereto about a second axis spaced from the first axis, and the operating lever being moveable between an open position and a closed position, and a linkage for opening an interrupter in response to movement of the operating lever when the pivot lever moves to the second position, for opening the interrupter in response to movement of the operating lever to the open position when the pivot lever is in the first position, and for closing the interrupter in response to movement of the operating lever to the closed position when the pivot lever is in the first position.

Abstract: Since industrial-rated circuit breakers are often located remote from the associated protected electrical equipment it is often times necessary to monitor the operation of such electrical equipment by observing the condition of the circuit breaker contacts to ensure that such equipment remains operational. When a plurality of such circuit breakers are mounted within a common enclosure, an auxiliary device within each of the circuit breakers readily provides visual indication of the ON-OFF condition of the circuit breaker contacts. With such auxiliary devices, an actuator-reset lever is used to interface between the circuit breaker operating mechanism, the circuit breaker trip mechanism and the auxiliary device to activate the auxiliary device when the circuit breaker contacts are open and closed and to reset the trip mechanism when the circuit breaker contacts are opened.

Abstract: A trip accelerator interfaces the thermal-magnetic trip unit and the operating mechanism within a thermal-magnetic molded case circuit breaker for improved response to overcurrent conditions within an associated electrical distribution circuit. The trip accelerator is in the form of a trip lever rotatably mounted on the operating mechanism side frame and is reset by the operating mechanism upon displacement of the circuit breaker operating handle.

Abstract: Self-coordinated device for the control and protection of electric motors and electrical equipment, for example, comprising, in a housing (2), a single control solenoid (5), a magnetothermal release device (M), a movable main contact (4) with a double break for each phase, which main contacts (4) are mounted on a contact-carrying bar (25) which is slidable and elastically preloaded (31), with which there interacts a composite mechanism (A) for the control of circuit-opening comprising two interacting mechanisms (B; C). One mechanism (B) interacts with the control solenoid (5) for desired circuit openings and for current surges. Both mechanisms (B; C) cause circuit-opening when short-circuit currents occur, more precisely with a double pushing action on the contact-carrying bar (25). The mechanism (C) also interacts with a locking mechanism (D) interacting in turn with a control knob (3) for the manual opening of the main contacts (4).

Abstract: A new single pole circuit breaker, intended for use in a multipole circuit breaker, is disclosed. Among other distinctions, upon being tripped, a relatively large torque is imparted to the trip lever of the single pole circuit breaker. This is achieved by interacting the contact bar stop pin on the contact bar of the single pole circuit breaker with a camming surface on the trip lever. In addition, when pivotal motion is imparted to the trip lever by an external agent, the trip lever directly engages the toggle mechanism of the circuit breaker, to collapse the toggle mechanism and produce tripping. Moreover, the trip lever has a configuration which permits convenient pivotal mounting to a frame.

Abstract: Field-installable accessories are used within a thermal-magnetic industrial-rated circuit breaker. On such accessory in the form of a combined undervoltage release and shunt trip unit is field-installable within the circuit breaker cover. A bell alarm accessory unit can also be inserted within the circuit breaker cover either in combination with or apart from the undervoltage-shunt trip accessory unit.

Abstract: A molded-case circuit breaker having an undervoltage release device housed therein is provided with a flexible molded double ended lever for resetting the undervoltage release device and a torsion spring braced upon the two arms of the lever so as to minimize the effects of stress and creep on the molded members when manually actuating repeatedly to reset the undervoltage release device against the biasing spring of the device.

Abstract: A circuit breaker embodies with a single electromagnetically actuated plunger two levels of actuation, corresponding to two levels of excessive current or voltage defined by two different airgaps, one at the lower level for triggering the toggle mechanism, the other at the higher level for directly actuating the movable arm through a kicker arm. The preferred embodiment provides a double-ended lever pulled by the plunger at midpoint for actuating the trip bar, and the kicker arm is actuated in an overriding situation by the lever rotating about the trip bar blocked at the end of its initial move.

Abstract: A residual current circuit breaker 1 has a partition wall 3 which separates an over-current protection device 4 from a residual current detection circuit 5. A plunger rod 24 extends through a bore 23 in the armature 21 of a coil 20 and is moved independently through the coil 20 to trip the breaker if a residual current is detected by the circuit 5. The plunger rod 24 is moved by a drive rod 31, the operation of which is controlled by a permanent magnet which retains the drive rod 31 retracted and an electromagnet which allows the drive rod 31 to drive forwardly under the action of a spring 32 in the event of a residual current being detected. The plunger rod 30 is reset by a reset lever 40 which is moved when an operating handle 18 of the breaker moves from a non-tripped to a tripped position upon tripping of the breaker.

Abstract: A measuring sensor of an electronic trip device of a circuit breaker comprises a shunt in the form of a hollow cylinder inside which there is located an electronic processing unit, comprising an amplifier circuit and an input resistance in good thermal contact with the internal face of the cylinder.

Abstract: An operating mechanism assembly used within molded case circuit breakers employing electronic trip units interconnects the operating mechanism with the circuit breaker movable contact arms by means of a slotted-cam arrangement. The slotted-cam optimizes the manual closing of the movable contact arms by controllably over-centering the circuit breaker operating mechanism springs.

Abstract: A circuit breaker is constructed to maximize the range of current over which it may operate, and to enhance its safety of operation in both single-pole and multipole embodiments. Improved operating devices are disclosed for both the manual and automatic modes of operation in single-pole or multipole embodiments.

Abstract: An integrated protection unit is a circuit interrupter which includes basic overcurrent protection facility along with selective electrical accessories. A molded plastic accessory access cover secured to the integrated protection unit cover protects the accessory components contained within the integrated protection unit cover from the environment. A combined overcurrent trip actuator and multiple accessory unit can be field-installed within the integrated protection unit. The combined actuator-accessory unit includes electronic control circuitry for the accessories along with mechanical trip and reset interface components. An actuator-accessory unit arranged within the interrupter cover interacts between the actuator-accessory unit and the interrupter operating mechanism to separate the interrupter contacts and interrupt a protected circuit.

Abstract: An integrated protection unit is a circuit breaker which includes basic overcurrent protection facility along with selective electrical accessories. A molded plastic accessory access cover secured to the integrated protection unit cover protects the accessory components contained within the integrated protection unit cover from the environment. A combined overcurrent trip actuator and multiple accessory unit can be field-installed within the integrated protection unit. The combined actuator-accessory unit includes electronic control circuitry for the accessories along with supplemental trip and reset interface components. The reset mechanism allows the actuator-accessory unit to become reset without interfering with the operation of the integrated protection unit. The trip interface components allow the circuit interrupter to interrupt a protected circuit by operation of the actuator-accessory unit.

Abstract: A molded case circuit breaker employs a multiple latch assembly for maintaining the circuit breaker operating mechanism in a closed condition. The multiple latch assembly includes three separate latch levers mounted on a common latch support frame. The multiple latch arrangement substantially reduces the amount of tripping force required to articulate the circuit breaker operating mechanism.

Abstract: A molded case circuit breaker includes an operating handle yoke that contacts the cradle operator and drives the operating mechanism springs over-center when the circuit breaker operating handle is moved from its RESET to its ON position. The contact between the handle yoke and cradle operator accelerates the over-centering of the powerful operating mechanism springs.

Abstract: A circuit breaker wherein a linkage transmits movements of a manual operating lever to a movable contact for moving the movable contact against a spring bias into engagement with a fixed contact. The linkage is arranged to hold the movable contact in an "ON" position and a releasable latch couples the linkage and the movable contact. A fault detector can effect release of the latch to permit the movable contact to move under the action of its spring from engagement with the fixed contact independently of movement of the linkage and the lever.

Abstract: A positive trip indication spring is used with circuit breakers that provide colored trip indication through a visual access opening in the circuit breaker cover to ensure that the trip indicia on the circuit breaker operating handle align with the visual access opening upon the occurrence of a trip condition. The trip indication spring cooperates with the powerful circuit breaker operating mechanism springs to provide additional bias to the circuit breaker operating handle to move the operating handle to its fully "TRIPPED" position.

Abstract: An integrated protection unit is a circuit breaker which includes basic overcurrent protection facility along with selective electrical accessories. A molded plastic accessory access cover secured to the integrated protection unit cover protects the accessory components contained within the integrated protection unit cover from the environment. A combined overcurrent trip actuator and multiple accessory unit can be field-installed within the integrated protection unit. The combined actuator-accessory unit includes electronic control circuitry for the accessories along with mechanical trip and reset interface components. The reset mechanism allows the actuator-accessory unit to become reset without interfering with the operation of the integrated protection unit.

Abstract: Trip device of the suction or pull-in armature type, having a yoke (18; 35) supporting a fixed permanent magnet (22) and a movable elongated armature (23) having a head member (25). The armature (23) and the yoke (18; 35) forming a first magnetic circuit for holding the armature (23) in a first position with the permanent magnet (22), in which first position the head member (25) protrudes outside the yoke (18; 35). For moving the armature (23) electromagnetically and/or electrothermally to a second position in which the head member (25) protrudes further outside the yoke (18; 35), the yoke (18; 35) is provided with electrothermal bimetal device (33; 37).

Abstract: An alarm switch operating apparatus for operating a plurality of circuit breaker alarm switches wherein a circuit breaker crossbar is further rotated from a tripped position by a rotation of a latch through a latch receiver during a tripping operation such that an alarm switch actuator is operated by the crossbar and wherein because the insulating bar of the crossbar extends across the left and right poles of the circuit breaker, the plurality of alarm switches are easily provided without damaging the insulation of the alarm switches.

Abstract: A circuit breaker has a magnetic trip assembly which can be adjusted to trip the breaker for low level overcurrents in the range of five to ten times rated current. The magnet trip includes for each pole of the breaker a helical torsion spring having one torsion arm which biases an armature against an adjusting bar to form a gap between the armature and a stationary magnetic structure in which magnetic flux strong enough to attract the armature and trip the breaker is induced by overcurrent. A second torsion arm of the spring has a first portion which bears against and slides along a pivot member carried by the adjusting bar to adjust the bias force applied to the armature by a given amount per unit travel of the adjusting bar over a low trip current portion of the range of travel of the adjusting bar.

Abstract: An assembly frame having first and second frame plates secures the movable parts of a breaker assembly together for ready assembly of the breaker assembly in a housing. A pivot pin supports the trip lever between the frame plates. The movable contact carrying blade has an elongated hole through which the pivot pin passes, the elongated hole forming a floating point for the pivot pin.

Abstract: A trip interlock assembly trips a circuit breaker any time the circuit breaker is removed from its panel mounting. The trip assembly is adapted to be disposed about a load side terminal and cooperate with the circuit breaker tripping device. In one embodiment, the trip assembly includes a housing and a spring-loaded actuation arm, disposed generally perpendicular to the circuit panel surface. The actuation arm is formed with a cam surface which cooperates with a trip pin adapted to actuate said circuit breaker tripping device. The trip pin acts as a cam follower and rides along the cam surface formed in the actuation arm. When the actuation arm is in an inward position the trip pin is in a normal position. However, when the circuit breaker is removed from the panel, the actuation arm under the influence of a biasing spring moves outwardly. This causes the cam surface on the actuation arm to actuate the trip pin to trip the circuit breaker.

Abstract: A fastenerless electromagnetic trip assembly employs minimal parts for effecting the release of a set of circuit breaker contacts. The parts include an armature, an armature bias spring, a yoke and a trip bar, all of which may be retractably supported in associated compartments within the circuit breaker housing. The yoke provides an electromagnetic field in response to electric current flowing in the circuit breaker. A spring biases the armature until the electromagnetic field reaches a predetermined strength, at which point the bias is overcome, and the armature strikes the trip bar and is drawn toward the yoke, thereby causing the trip member to actuate the release of the circuit breaker contacts.

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 circuit breaker is constructed to maximize the range of current over which it may operate, and to enhance its safety of operation in both single-pole and multipole embodiments. The operating mechanism for both manual and automatic modes of operation in single-pole or multipole embodiments of the circuit breaker is improved.

Abstract: An operating mechanism of an electrical circuit breaker comprises a handle coupled to a transmission rod to form a toggle, a movable contact support device having a plate mounted with rotation on a pivot, and a mechanical link breakable by the action of a trip lever. The link is formed by a retaining catch of the trip lever cooperating with a latch pivotally mounted on a spindle of the plate. The rod is coupled directly to the latch, the assembly constituting a gearing-down stage enabling the tripping force to be reduced. The bimetal strip is connected to the trip lever by a rotating tie-rod with uni-directional transmission.

Abstract: An integrated protection unit is a circuit breaker which includes basic overcurrent protection facility along with selective electrical accessories. A molded plastic accessory access cover secured to the integrated protection unit cover protects the accessory components contained within the integrated protection unit cover from the environment. A combined overcurrent trip actuator and multiple accessory unit can be field-installed within the integrated protection unit. The combined actuator-accessory unit includes electronic control circuitry for the accessories along with mechanical trip and reset interface components. The reset mechanism allows the actuator-accessory unit to become reset without interferring with the operation of the integrated protection unit.

Abstract: An electronic circuit breaker having withstand capability. When the fault current exceeds the required withstand level, the mechanism force trips the circuit breaker. The forces generated by a blow-on contact loop are exerted on the various components of the operating mechanism, including the quick trip latch and secondary latch. As the fault current exceeds the required withstand level, the forces on the operating mechanism exceed the spring force holding together the quick trip latch and secondary latch. These two components rotate as one assembly during a trip operation initiated by energizing the trip coil. In the force trip operation, these two components separate unlatching the mechanism and opening the circuit breaker contacts.

Abstract: A circuit breaker mechanism has an armature component that is slidably displaceable between latched and tripping positions. The armature is connected to a moving contact carrier that is pivotally connected to an operating handle that is also pivotal. The armature is connected to the carrier by a spring. The armature has a latching formation which engages a projection. When tripped,the armature is slightly pivoted to clear the projection.

Abstract: An integrated protection unit is a circuit breaker which includes basic overcurrent protection facility along with selective electrical accessories. A molded plastic accessory access cover secured to the integrated protection unit cover protects the accessory components contained within the integrated protection unit cover from the environment. A combined overcurrent trip actuator and multiple accessory unit can be field-installed within the integrated protection unit. The combined actuator-accessory unit includes electronic control circuitry for the accessories along with mechanical trip and reset interface components.

Abstract: In a trip relay mechanism (50) of circuit breaker wherein a latch (23A), a latch lever (25A) and a trip bar (34) are urged to engage with each other; the trip bar (34) is disposed between the latch (23A) and the latch lever (25A) in the direction of power source side-load side of the circuit breaker and they (23A, 25A, 34) are urged by one double-torsion spring (35), and further the trip bar (34) is separated into a main part (34B) extended over each pole and a latching part (34A) for engaging the latch lever (25A).

Abstract: A trip bar interlock for a circuit breaker characterized by an electrically insulating housing having an apertured bottom wall. A rotatable trip bar is in the housing for releasably holding the circuit breaker in an untripped condition. An actuator is provided for releasing the trip bar when the circuit breaker is dismounted from a mounting surface. The trip bar and the actuator have engaging surfaces and the actuator has an end portion extending through the aperture. The actuator is biased toward the mounting wall.

Abstract: A switch latch for a power switch including a supporting part of the type having two planar, parallel connected bearing plates, a switching mechanism adapted to hold a lock mechanism, wherein the levers of the switch latch are configured as planar members, simple pins are used as bearing pins and as connecting pins, and simple tension springs serve as spring elements, wherein one side of each bearing plate projects to form an assembling tab which projects at right angles to another portion of the respective bearing plate, and the bearing plates are connected with one another by an assembling bracket connected at the side opposite the tab ends, with the assembling bracket being configured as a planar member.

Abstract: There are arranged at a magnetic trigger for a selectively operative switch, a plunger-type armature, a pivotable armature and a tripping device. A plunger of the plunger-type armature acts directly upon a movable contact of a pair of contacts and the plunger-type armature is actuated using a magnetic coil or winding when the current flowing through the magnetic coil at least corresponds to a predetermined threshold current for opening the contacts. A pivotable armature is actuated by the plunger-type armature and redirects the magnetic return flux. The tripping device acts upon a switch lock mechanism and is switched into or out of the magnetic return flux by the plunger-type armature. The degree of overlap between pole shoes of the pivotable armature and of the tripping device is preselectable by an adjusting screw. There is thus realized a current-dependent, selective tripping of the switch lock mechanism.

Abstract: A switch assembly especially suitable for use as part of an overall electrical circuit breaker is disclosed herein. This switch assembly includes a three-link arrangement consisting of three links interconnected together for movement between a first positional configuration in order to open a circuit and a second positional configuration in order to close and circuit. A mechanism is provided for applying a force to the linkage arrangement in a way which causes the links to open from a closed position, that is, to move from their first positional configuration to their second positional configuration, and thereafter for maintaining the links in their open configuration.

Abstract: An industrial rated molded case circuit breaker having an electronic trip circuit contained within the circuit breaker enclosure includes a reset spring in cooperation with the circuit breaker latch spring to insure manual reset of circuit breaker after an automatic trip function. The reset spring allows the circuit breaker latch assembly to be manually reset upon minimum travel of the circuit breaker operating handle due to internal circuit breaker component space restrictions. The circuit breaker latch assembly is robotically loaded to the operating mechanism which is then attached to the circuit breaker case by an automated fastening process.

Abstract: A circuit interrupter comprising an automatic trip unit connected to an interrupting unit for tripping the interrupting unit to open separable contacts in response to an overcurrent, the automatic trip unit being a replaceable unit selected from a plurality of differing types of trip units including an electronic trip unit and a thermally responsive electromagnetic trip unit.

Abstract: A circuit breaker has an insulated casing including an upper casing portion and a lower casing portion. A switching mechanism is attached to a frame which is seated in a positioning recess portion of the lower casing portion. The frame and switching mechanism are captured by extending support arms of the lower casing portion and are fixedly secured thereto to permit operation of the switching mechanism prior to final assembly of the upper and lower casing portions.

Abstract: In a circuit interrupter having a base with a stationary contact, a toggle link mechanism including an operating handle supported by the base for manually operating the circuit interrupter and a link rotatably connected at one end to the operating handle; a movable member pivotally supported on the base and having a movable contact on one pivoting end portion; a latch lever pivotally supported on the base for latching the link so that the movable member and the link are normally connected to hold the movable member against the force of a biasing spring so that the contacts are in engagement, and an overcurrent trip means including a plunger actuated responsive to a large overcurrent to strike and pivot the latch lever so as to release the link from the movable member to move and separate the contacts, the improvement comprising a pivotal support for the latch lever and the movable member on the base, allowing both bodily movement and pivotal movement only of the movable member; the pivotal support including a

Abstract: A circuit breaker operating mechanism for automated assembly finds application within circuit breakers of different ampere ratings. The circuit breaker contacts are opened and closed by means of a roller connected to the circuit breaker operating handle through a cradle link and a cam arranged on the movable contact carrier. The operating springs, cradle and latch are first assembled to the operating mechanism prior to assembly of the operating mechanism within the breaker housing.

Abstract: A circuit breaker has a metal frame (10) disposed on a base of a housing. A trip-bar (6) made of molded plastic of like material is rotatably held on the frame (10) by insertion of a trip-bar pin (15) into a center through-hole provided on the trip-bar, and pinchers (14,14) of the trip-bar (6) pinch the trip-bar pin by elasticity of the plastic material to hold the same in place with very little lateral play.

Abstract: A push-to-trip button for a circuit breaker characterized by a circuit breaker within an insulating housing and having trip means for releasably holding a circuit breaker operating mechanism in an untripped position and including a trip bar biased in an untripped position, a trip delay member biased away from the trip bar and including an adjustment bar for applying a pressure on the member, a trip button extending through the housing and having a first surface contacting the trip bar, and the adjustment bar having a second surface for applying limited pressure on the trip button for holding the first surface in contact on the trip bar, without moving the trip bar to a tripped position.