Abstract: A latch mechanism for a circuit breaker comprises a pair of longitudinal legs, a lateral section bridging the pair of longitudinal legs, and a longitudinal section extending from the lateral section in an opposite direction relative to the pair of legs. The lateral section includes a lower bearing surface for releasably engaging a cradle of the circuit breaker. The lower bearing surface includes a coined radius for facilitating engagement and disengagement of the cradle. The longitudinal section includes a protrusion for supporting a latch spring. The latch mechanism is manufactured in a single stamping operation, during which the protrusion is formed by cold extrusion.

Abstract: A bimetal controlled circuit breaker includes a current bus that is electrically connected in series with the bimetal element. The current bus extends parallel to the bimetal element in the deflection plane of the latter and is rigid relative to the bimetal element. The deflection of the bimetal element is supported by the action of electrodynamic forces. In order for the circuit breaker to be suitable for greater current intensities and the effect of the electrodynamic forces to be better utilized, the bimetal element is electrically connected in parallel with a shunt path.

Abstract: A molded case circuit breaker having a thermal-magnetic trip unit is provided with a mechanical rating plug to allow a number of circuit breakers of different ampere ratings to be used within a common-sized enclosure. The rating plug interacts with a thermal-magnetic trip unit to set the circuit breaker ampere rating.

Abstract: An overcurrent tripping device which is included in a circuit breaker is constituted by a pre-assembly unit of a holder with a conductor, a fixed core for generating a magnetic attraction force responding to an overcurrent, and a bimetal warping responding to the temperature rise of the conductor, and an operation arm rotatably borne on the holder and having a moving core which is to be attracted to the fixed core by the magnetic attraction force.

Abstract: A molded case circuit breaker for residential use employs an additional safety feature to ensure a fail-safe condition in the event that the circuit breaker is installed within a circuit that may be subjected to an excessive over-current fault that disables the circuit breaker trip unit. The integral bimetal-fuse within the circuit breaker trip unit responds to interrupt circuit current before any damage can occur to the associated electrical wiring system.

Abstract: An electric circuit breaker operating mechanism includes an insulated armature latch which prevents deleterious arc formation between the operating mechanism cradle and the armature latch surface when the circuit breaker contacts are separated under overcurrent circuit conditions. The insulated armature latch carries a tolerance take-up spring which interacts between the operating mechanism cradle and the circuit breaker trip bar assembly to insure free travel of the operating cradle during contact separation.

Abstract: A method of manufacturing a circuit breaker comprises the steps of preassembling the movable parts of the circuit breaker between a pair of frame members and providing a housing that is configured for supporting the unitary breaker assembly without attachments. Other circuit breaker components, attached to the unitary breaker assembly, are also supported in the housing without attachments. A cover is secured to the housing to complete the circuit breaker. Another version of the invention preassembles the movable parts of the circuit breaker and the stationary contact mechanism and trip coil, with the line and load terminals attached, between a pair of supporting frame members to form an operable circuit breaker module. The module is in turn supported in a housing without attachments. The circuit breaker module may be tested and adjusted prior to final assembly.

Abstract: An improved miniature circuit breaker is provided which is adapted to improved automatic assembly of all components thereof. Key components of the breaker are individually and collectively designed to be susceptible to total Z-axis assembly. In particular, the magnetic-yoke and armature which comprise the current response mechanism for the circuit breaker are designed to interact with each other so that the magnetic armature can easily be Z-axis assembled onto the magnetic yoke.

Abstract: An improved miniature circuit breaker is provided which is adapted to improved automatic assembly of all components thereof. Key components of the breaker are individually and collectively designed to be susceptible to total Z-axis assembly. In particular, the trip mechanism including the trip lever, and the associated activation means, tension means and reset means are defined by elements designed to interact in a Z-axis assemblable fashion. The trip mechanism components are also designed for improved trip action and enhanced breaker performance in repeated OPEN, CLOSED, and TRIP operations.

Abstract: An improved tripping mechanism for use in a circuit breaker wherein magnetic tripping is responsive to low levels of overcurrent by limiting the depth of engagement of a trip lever of a cradle with respect to the latch engagement tab of the armature. Responsiveness of the magnetic tripping is enhanced by positioning of the magnetic yoke adjacent to the bimetallic member while at the same time being movable with respect to the bimetallic member. Positioning the magnetic member independently of the position of the bimetallic member facilitates having magnetic tripping responsive to low overcurrent conditions while at the same time allowing thermal tripping by movement of the bimetallic member to be fully maintained.

Abstract: A molded case thermal-magnetic circuit breaker having improved low current magnetic trip response pivotally arranges the magnet within the circuit breaker thermal-magnetic trip system for controllably moving toward the latching armature assembly. The movement of the magnet decreases the magnetic separation distance between the magnet and the latching armature to optimize the magnetic trip forces and thereby enhance low current magnetic trip response.

Abstract: A sensor for measuring concentrate of solute in an aqueous solution in which a humidity sensor is enclosed and sealed within a porous fluorine polymer film that is liquid water impermeable but water vapor permeable. The sensor operates by measuring water vapor pressure in the gaseous phase inside the sealed film after the inside and outside have equilibrated with respect to water outside and inside.

Abstract: A circuit breaker having a housing, fixed and movable contacts respectively supported by a fixed contact support structure and a movable contact arm, a trip mechanism, and an operating mechanism which is releasably engageable with the trip mechanism. The operating mechanism includes a pivotable operating member and a tension spring. The fixed contact support structure includes a contact supporting leg portion. The movable contact arm has a contact supporting side, and an opposite spring supporting side. The tension spring links the pivotable operating member and the spring supporting side of the movable contact arm. The contact supporting leg portion of the fixed contact support structure and the movable contact arm are disposed in closely spaced relation when the fixed and movable contacts are in engagement, to provide a reverse current loop which magnetically assists in rapid contact separation.

Abstract: A molded case thermal-magnetic circuit breaker having improved low current magnetic trip response interfaces an intermediate armature between the circuit breaker latching element and the magnet assembly within the circuit breaker thermal-magnetic trip system. The intermediate armature optimizes the magnetic trip forces applied to both the intermediate armature and the latching element to enhance low current magnetic trip response.

Abstract: A molded case thermal-magnetic circuit breaker having improved low current magnetic trip response pivotally arranges the magnet within the circuit breaker thermal-magnetic trip system for controllably moving toward the latching armature assembly. The movement of the magnet decreases the magnetic separation distance between the magnet and the latching armature to optimize the magnetic trip forces and thereby enhance low current magnetic trip response.

Abstract: A molded case circuit breaker utilizes a thermally responsive trip unit for providing long and short-time overcurrent protection and a magnetically responsive trip unit for instantaneous or short-circuit protection. An electrically and thermally insulative lever interfaces between the thermal element and the circuit breaker trip response bar to linearize the movement of the thermal trip element in response to circuit current.

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: A molded case circuit breaker is provided with a magnetic trip unit which includes an armature assembly and a multi-turn magnetic coil assembly. The magnetic coil assembly is formed to occupy substantially the same volume as a single-turn magnetic coil. The added turns in the magnetic coil increase the attraction force on the armature to essentially lower the electric current value at which the magnetic unit trips the circuit breaker. By utilizing a multi-turn magnetic coil assembly which occupies the same space as the single-turn magnetic coil, the same frame size can be used for both single-turn magnetic coils, and multi-turn magnetic coils without the need to locate the thermal unit outside of the molded case circuit breaker.

Abstract: An electric current responsive actuator has a thermally responsive force generator and an electromagnetically responsive force generator. The force generators are coupled together to produce a resultant force on a movable trip actuator. In the preferred specific embodiment of the invention, a shape-memory alloy element serves as the thermally responsive force generator.

Abstract: A limiting circuit breaker with a molded case comprises an overpressure actuator which, when an overpressure occurs in the arc extinguishing chamber due to the action of an arc drawn by the electrodynamic repulsion of the contacts, brings about actuation by a piston, subjected to this overpressure, of the circuit breaker trip bar. The overpressure actuator forms an almost leaktight assembly.

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: 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 accessory module (104) for use with a circuit breaker (10) is configured for mounting to the breaker, and has a rotor (142) which follows the movement of the circuit breaker blade (24) in the breaker by means of a coupling member (118) passing through a passage (110) in the circuit breaker wall. A portion of the rotor is configured as a cam (162) operating a switch (152) in the module, the switch thus giving a reliable indication of the position of the breaker blade. The breaker is preferably of the type which has a trip lever (50) carried on the breaker blade and mounted for slight movement thereon, and the rotor is preferably coupled to the trip lever. A solenoid (148) within the accessory module is disposed to rotate the rotor when energized, this rotation being coupled to trip the breaker to provide for remote tripping. Since the trip lever is carried with the breaker blade, the blade position is monitored by the switch.

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 circuit breaker combines DC and AC arc extinguishing capabilities by associating a magnet applied permanently upon the outside wall of the insulating housing of the breaker and a U-shaped member of ferromagnetic material lodged and held inside the housing, both being in line with the centrally disposed arc chamber and the fixed and stationary contacts thereof.

Abstract: A twin unit circuit breaker has a V-shaped stainless steel combination armature pivot and bias spring, a central offset portion on the armature to increase the armature surface area that is substantially uniformly spaced to pole faces of a pole piece, a thin profile connection of an operating spring with a latch lever, and a preformed U-shaped conductor attachable in circuit between a bimetal and a flexible conductor and insertable over a pole piece from one end thereof.

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: 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: In a transformer primary circuit breaker having a primary switch for opening and closing the transformer primary circuit, an operating handle mounted exteriorly of the transformer for opening and closing the primary switch, a trip mechanism operatively connected to open the primary switch under fault current conditions, the trip mechanism including a conductive metallic sensor element connected in the primary circuit and having a predetermined Curie temperature and a magnet mounted for movement into engagement with the sensor element and biased to open the primary switch when the temperature of the sensor element approaches the Curie temperature, the improvement comprising a shunt circuit connected to the primary circuit in parallel with the sensor element, a normally closed switch in the shunt circuit, a resistance element for limiting the current passing through the shunt circuit, and a tab mounted on the operating handle for opening the shunt circuit switch, a spring mounted in the operating handle for lim

Abstract: A circuit breaker structure having a faster trip unit characterized by a circuit breaker operator and a trip unit comprising a coil, a core, and an armature, and a hold-back bracket extending from and retaining the armature in a spaced position from the core so as to cause the magnetic field lines to flow through the bracket and the armature.

Abstract: A mechanism prevents the start-up of a synchronous a.c. motor in other than a desired direction. The mechanism includes a flexible arm having a finger that will engage a radially projecting abutment on the motor shaft. The finger blocks rotation of the shaft in a first direction and slides over the abutment when the shaft rotates in the opposite direction. A solenoid moves the arm and finger out of the path of the abutment shortly after the motor is energized, to allow the shaft to rotate in the first direction if the motor encounters an overload. Alternately, the arm may be formed of a bi-metal which is differentially heated by electrical current following motor energization to move the arm out of the path of the abutment.

Abstract: The invention relates to a multiple moving contact assembly for a miniature circuit breaker with high ratings and a thermomagnetic trip release. The moving contact part of the circuit breaker includes two independent contact arms connected in parallel and mounted on a transverse spindle of the cradle. The arms are connected to a magnetic circuit of the electromagnetic trip release by two braids situated in symmetrical lateral areas. The contact parts bear on a single stationary contact pad so as to create two contact points enabling the temperature rise to be reduced. The electromagnetic top release has a coil including a tail arranged as an adjustable support device of a bimetallic strip, through whose foot the current flows thicknesswise.

Abstract: A circuit-breaker which includes a housing, an actuator device positioned in generally upstanding relationship to and centrally of the housing, thermal trippers and magnetic trippers mounted on one side of the actuator device, an electromagnetic drive including an armature for operating an associated element, the electromagnetic drive being mounted on a side of the actuator device opposite the thermal and magnetic trippers, a pair of pivotally connecting links, the links being operated by a pivoted yoke by energization of the armature, one of the links having a nose received in a slot of a slide, and the magnetic and thermal trippers also having noses received in slots of a slide such that selective turn-on and turn-off conditions can be achieved manually or automatically.

Abstract: A circuit breaker apparatus characterized by a molded case containing a circuit breaker structure for opening and closing a circuit which structure comprises a releasable lever operable between latched and unlatched positions corresponding to open and closed circuit conditions, latch means including a latch lever for the releasable lever, interconnected toggle connected to the latch lever and that are biased to the unlatched position of the lever, and a movable trip bar responsive to predetermined overcurrents and having a projection contacting the toggle links for holding the links in the unbiased position.

Abstract: An interchangeable operating mechanism assembly for molded case circuit breakers having a detachable movable contact arm and trip unit assembly allows the same mechanism assembly to be employed across a wide range of breaker ratings. A snap-on common trip bar attachment further allows multiple-pole facility off the common interrupter mechanism assembly. The mechanism assembly is designed to maintain the operating handle in the "on" position upon the occurrence of a welded contact and prevents the mechanism from being reset.

Abstract: A protective switching apparatus is provided comprising in an insulating case an interruptible current path in which cooperating contacts are disposed, one of which is fixed and the other is mobile in response to the actuation of a tripping member. The mobile contact is disposed at a first end of a contact holder arm whose second end is associated with a retractable fulcrum forming the output member of the lock, the contact holder arm being subjected to the action of a resilient quick opening means and to the action of a resilient closure means. The contact holder arm is mounted without fixed fulcrum, so as to pivot either by bearing against a bearing surface of the toggle joint during tripping on a fault, or against a bearing surface of the retractable fulcrum of the lock during voluntary manual or automatic tripping.

Abstract: A circuit breaker has a bimetallic element and an electromagnetic element. The bimetallic element has one end connected to the line terminal and the other end connected to the pigtail connector. A shunt is connected at one end to the pigtail connector and has a contact on the other end matable with the line terminal contact. The shunt is connected at one end to the pigtail connector immobilizing the pigtail so that it does not interfere with the operation of the bimetallic element. The electromagnet is positioned about the bimetallic element and has an armature which is movable to trip the circuit breaker. The shunt element has a spring connected which biases the armature away from the electromagnet.

Abstract: A composite line strap is used with molded case circuit breakers to support the circuit breaker stationary contact and to retain the circuit breaker line terminal screw. The fixed contact is welded to the line strap within the breaker at a first end and the line terminal screw is attached to the opposite end of the line strap by a through-hole in a spring-steel retainer which extends partially within the circuit breaker. The line terminal screw is tightly held within the through-hole of the retainer at the first end and the retainer itself is trapped between the bottom of the circuit breaker case and the line strap at the opposite end of the line strap.

Abstract: A circuit interrupter comprising a pair of separable contacts at least one of which is movable, and an operating mechanism operatively connected to the movable contacts for opening and closing the contacts. The operating mechanism includes a movable contact arm having mounted thereon the movable contact, a latch lever pivotally mounted on the movable contact arm, and a toggle link mechanism connected at its one end to an operating handle and the other end of which is directly engageable with said movable contact arm and the latch lever. The movable contact arm has a latch surface, and the latch lever has a latching end which, in cooperation with the latch surface, releasably catches the other end of the toggle link mechanism.

Abstract: A circuit breaker characterized by a circuit breaker structure having separable contacts and a releasable mechanism which mechanism is retained in untripped position by a latch including a rotatable trip bar. A solenoid, that is operable automatically in response to overload current conditions, is located adjacent to the trip bar and has a plunger movable parallel to the axis of the trip bar. A lever is disposed between the plunger and the trip bar to translate longitudinal motion into rotational trip bar motion.

Abstract: An automatic switch comprised of a dual-contact switch mechanism, a bimetallic thermostatic element, a solenoid-style tripping device, and an arc chamber complete with deionization plates. To eliminate one of the three electrical-hook-up steps (one, the physical attachment to a mounting, and the two electrical terminal connections), a group of components is provided for the switch assembly, including a plug-like terminal, which forms one end of the switch's electrical terminals on the rear housing wall, and an additional snap-action holding element disposed at the distal part of the rear housing wall from said plug-like terminal. The automatic switch incorporating these components can thus be snap-mounted onto a conductor rail by means of said plug terminal and onto a separate nonconductive mounting bar or rail--all in a single step. The remaining conductor can be wired-up in the traditional way thereby placing this switch in a circuit by only a two-step procedure.

Abstract: An improvement to prevent alteration of the circuit breaker calibration due to high overloads. A circuit breaker has a U-shaped current path with a brazed junction at the bend of the "U". Upon the occurrence of a large overload, the opposing current in the two legs of the U-shaped path will force the two legs of the "U" apart, possibly weakening the brazed junction. When one of the legs is a closely calibrated component of a trip assembly, the breaker will no longer operate within the proper range. A stop is placed within the housing to prevent the two legs from moving apart such a distance as will cause the brazed junction to fail.

Abstract: An automatic electric side-by-side two-pole circuit breaker having an insulating casing formed from the complementary association of a base casing, an intermediate casing and a cover which provide a pair of mechanism receiving compartments in side-by-side association. Each compartment carries a pivotally supported operating handle which extends partially outward from the casing for external manual operation, a line terminal, a load terminal electrically connected to said line terminal, a stationary contact intermediate said line terminal and said load terminal and a movable blade which carries a movable contact on one end and has its opposite end connected to the handle. A releasably latched generally thin trip lever is pivotally mounted within the compartment and is releasable from its latched position to a tripped position to effect separation of the contacts. The trip lever includes an upstanding leg which is engaged by a protuberance on the handle for resetting the trip lever.

Abstract: A circuit breaker characterized by a roller guide member, 1a, provided on the inside wall of an upper part of the case 1. The roller quite member, 1a, has a curved shape designed to form or smooth curved path, 100, in cooperation with the roller receiving indents 5a and 56, so that the roller can be reliably reset in the roller-receiving indents 5a and 5b.

Abstract: A circuit interrupter which comprises a pair of separable contact structures each including a contact element, at least one of the contact structures being movable between a closed position and an open position relative to the other contact structure for opening and closing an electric circuit extending through the circuit interrupter, the movable contact structure having an arm support that is pivotable about an axis, a movable contact arm pivotally supported on the arm support and extending in a parallel and an opposite direction to the other contact structure for generating an electromagnetic repulsive force therebetween, and a biasing means connected between the arm support and the movable contact arm for biasing the movable contact arm to a predetermined position with respect to said arm support, and an operating mechanism connected to the arm support of the movable contact structure for separating the movable contact structure from the stationary contact structure in response to an overcurrent flowing t

Abstract: A compact equipment protecting electrical circuit breaker having a short-circuit and excess current tripping action as well as a signal change switch for actuating and protecting household appliances, office machines, manufacturing devices and the like, includes a breaker and tripping mechanism which is a combination of a cocking body (5) with an unlatching lever (4) supported therein, a tilting contact piece (6), and a cam lever (14) with the functional inclusion of several spring elements. The combination is mounted on a common axis in a central location below the operating mechanism (1-3) and between the hinged armature system (8) and a bimetal strip (10). The combination is further located or mounted above an arc quenching chamber (12) and above a signal change switch contact device (13) and above the various breaker terminals (15). The change switch has its own terminals for signalling the instantaneous operating condition of the circuit breaker.

Abstract: A temperature-responsive trip assembly for a primary circuit breaker, the assembly including a permanent magnet member biased to a circuit opening position and pertinent to engage a thermally-responsive metallic element having a predetermined Curie temperature, the element being formed of a nickel-iron alloy having approximately 32% nickel and being arranged in edge-abutting relation to the magnet.

Abstract: A circuit breaker including a mechanism comprising an on-off mechanism unit for opening or closing the electric circuit and a trip mechanism unit for cutting off the closed circuit, the on-off and trip mechanism units being coupled independently of each other and relating to each other only when the circuit breaker is tripped, but not when open or closed, thereby aiming at diminution in the time from detection of abnormality to disconnection of contacts, an increase in a distance between the disconnected contacts, and stabilization of trip characteristic, thus improving the cutoff performance.

Abstract: A molded case circuit breaker includes a highly integrated operating mechanism having an over-center toggle mechanism for opening and closing a pair of electrical contacts and a trip mechanism for responding to overload and short circuit or fault current conditions to separate the pair of electrical contacts. A generally flat, intermediate latch plate includes an upper latch surface for latching with a movable cradle of the over-center toggle mechanism and a lower latch surface for latching with a trip bar of the trip mechanism and a pair of outwardly projecting pivot arms disposed between the upper and lower latch surfaces. The over-center toggle mechanism includes a pair of upper toggle links and a pair of lower toggle links interconnected by a toggle spring pin.

Abstract: A circuit breaker characterized by a roller guide member, 1a, provided on the inside wall of an upper part of the case 1. The roller quite member, 1a, has a curved shape designed to form or smooth curved path, 100, in cooperation with the roller receiving indents 5a and 56, so that the roller can be reliably reset in the roller-receiving indents 5a and 5b.