Abstract: An overload relay comprising three modules, each enclosed in molded housings: the basic unit, the contactor-side terminal block and the load-side terminal block. Both terminal blocks have phase connectors which can be the same or different in terms of their type of connection and/or their clearance between phases and/or their phase height. The terminal blocks can be mechanically and electrically detachably connected to the basic unit. At least the basic unit or the terminal blocks have means for fastening to a mounting plate. In an additional solution, the terminal blocks are part of a series which is compatible with at least two different contactors. A typical field of application for the invention is the protection of electric motors.

Abstract: Each breaking module is formed by a parallelepipedic monoblock cartridge made of plastic material, housed in the corresponding compartment of the base plate, said cartridge housing at least a stationary contact, an arc extinguishing chamber, and a pair of connecting strips for connection to a terminal and to the trip module of the same pole. A mechanical actuation module constituted by the switching bar and mechanism assembly, is securedly united to the cover. The rotary trip bar is supported by clipping means, arranged on the bottom face of the cover. A plurality cf recesses and cutouts are arranged in the spacers of the base plate to act as first bearing surfaces respectively for the switching bar and trip bar when the first sub-assembly A composed of the base plate with the set of breaking modules and trip modules, is adjoined with the second sub-assembly B formed by the cover on which the mechanical actuation module, trip bar and latch are fitted.

Abstract: A circuit breaker has a pair of poles, either of which can experience a ground fault. A sensing device senses an imbalance of current between the phases and neutral, and a trip device responsive to the sensing device simultaneously trips both of the poles when an imbalance of current (ground fault) is sensed in either of the poles. The trip device includes a trip lever engageable with each of the poles and a single solenoid for controlling operation of the trip lever.

Abstract: A relay module, by which a time required when a motor is optionally mounted on a machine tool or removed therefrom can be omitted. The relay module comprises only a case and terminal screws of an electromagnetic contactor for a motor from which internal components are removed. The relay module is disposed when the motor is not connected and an electromagnetic switch is disposed when the motor is connected. Further, the relay module or electromagnetic switch is wired at all times. When the motor is optionally mounted on the machine tool, it suffices only to replace the relay module thereof with the electromagnetic switch and no wiring job is additionally required. Further, when the motor is removed, it suffices only to replace the electromagnetic switch with the relay module and a job for removing the wiring is not necessary.

Abstract: A miniature circuit breaker with two thermal-magnetic poles has an electronic trip device providing ground fault, and sputtering arc fault (if desired), protection located entirely in a large central compartment of a molded housing between compartments housing the two mechanical poles. The current rating of the circuit breaker is increased by a gas vent channel extending between the two mechanical pole compartments adjacent the respective breaker contacts which allows gases generated by arcing during current interruption to expand into both outer compartments, thereby permitting the circuit breaker to interrupt larger short circuit currents. The gas vent channel extends through, but does not communicate with, the central electronics compartment.

Abstract: A removable calibrating unit comprises a body, a front panel and a part in the form of a reversible ramp. The reversible ramp comprises an end close to the front panel and an end away from the front panel. Extraction of the removable unit is achieved by means of a pin comprising an extraction lug. When the pin is subjected to rotational movement in one direction, the lug moves from the end close to the front panel to the end away from the front panel and results in extraction of the unit by applying thereon a force separating the unit from the circuit breaker.

Abstract: A molded case circuit breaker containing a digital trip unit is field-tested for both electronically-induced as well as mechanically-induced test conditions by means of a portable test kit unit. The test kit circuit components are contained within a miniature test plug that temporarily connects with the circuit breaker trip unit by insertion within the rating plug receptacle formed within the circuit breaker cover. A compact power supply plug is received within the test plug to provide operating power to the circuit breaker trip unit components and associated accessories.

Abstract: A ground fault module is provided for protecting a circuit interrupter connected between the load and line terminals of a phase and neutral power line. The module includes a sensor for detecting a current imbalance between the phase and neutral power lines. A phase conductor having a rigid, elongated body made of solid, electrically-conducting material with a first and second end is adapted for connection to the load and line phase power line. A neutral conductor having a rigid, elongated body made of solid, electrically-conducting material with a first and second end is adapted for connection to the load and line neutral power line. Preferably, terminals are used to clamp the ends of the phase and neutral conductors to the load power line and load neutral line. The phase and neutral conductor are operatively connected to the sensor.

Abstract: A molded case circuit breaker enclosure and operating components are provided with additional features to enable compliance with a variety of international electrical requirements for sales in the world market. The circuit breaker operating handle is prevented from returning to the OFF position upon contact welding as one example. Another modification includes a reinforcement and rejection pin used with the enclosure case. A further modification includes a shield used with the movable contact arm to prevent the arc gas contaminants from contacting the circuit breaker operating springs.

Abstract: A reed switch assembly and method of assembling it are disclosed. A preferred embodiment of the reed switch assembly includes an elongate hollow housing having an opening at one end thereof for access to a cavity therein. A reed switch is positioned completely inside the cavity. The first and second connecting leads of the reed switch are bent so that they are each substantially parallel to their respective first and second reeds and so that they lie in planes that are not coplanar with the flat portions of the first and second reeds. The first connecting lead has a length that is long enough so that it extends at least half-way over the reed switch body towards the second connecting lead. A first wire is attached to the first connecting lead at a connection point that is spaced apart from the free end of the first connecting lead a distance equal to at least one-half the total length of the first connecting lead.

Abstract: In this closed type electromagnetic relay, an insulating resin is injection molded to the surface of a coil block so that a part of a coil wound around an iron core at the side opposite a contact opening/closing mechanism is exposed. A force exerted on the coil by the resin pressure during injection molding is relieved by the exposed part, and a gas generated from the coil or the like after the injection molding is discharged out through the exposed part. Accordingly, the coil block is easily coated with the insulating resin without fears that the coil is broken at sealing time or the coated resin is broken after sealing.

Abstract: A molded case for a miniature circuit breaker provides a base and a cover whose outer mating peripheral walls, which form and enclose a cavity for housing a circuit breaker mechanism, have approximately equal widths, except for the projected handle area. In this handle area, the width of the peripheral wall of the base is increased and contains an aperture for receiving the handle, and the width of the peripheral wall of the cover is decreased to receive the increased aperture area of the base. This arrangement provides for full handle support in the base for ease of assembly; high ribbing for maximum strength for short circuits; and a minimum overall thickness of about 0.500 inches.

Abstract: A case for a circuit breaker provides a base and a cover, both having an inner surface ribbing system and an inner surface coring system. The ribbing systems form an inner cavity retaining a circuit breaker mechanism and an outer aperture area for receiving a handle for manual operation of the mechanism. The handle is supported in the arcuate areas of the coring systems near the aperture area. A barrier member is located adjacent to the arcuate area in the base, and a barrier member is located adjacent to the arcuate area in the cover. When the base and the cover are assembled the two barrier members are spaced away from the handle and overlap the handle in the arcuate areas to separate the outer aperture area containing the handle from the inner cavity containing the circuit breaker mechanism and still allow the handle to extend freely down into the inner cavity for its connection to and operation of the circuit breaker mechanism. The width or thickness of the barrier member in the base is about 0.

Abstract: A mid terminal for a double break circuit breaker comprises first and second elongated conductive plates, where each of the plates have first and second ends. The second end of the first plate is longitudinally spaced from the first end of the second plate and the first end of the first plate is connected to the second end of the second plate by a lateral conductive plate. A first are runner is electron beam welded to the second end of the first plate, and a second are runner is electron beam welded to the first end of the second plate. The first and second arc runners are preferably made of steel. A first stationary contact is mounted on the first plate adjacent the first arc runner, and a second stationary contact is mounted on the second plate adjacent the second arc runner.

Abstract: A molded case circuit breaker unit having an accessory compartment within the circuit breaker cover, contains a field-replaceable fuse within the compartment for protecting an electric motor without tripping upon motor current reversal. Upon the occurrence of a short circuit within the protected circuit, the fuse operates to isolate the protected equipment and is conveniently replaced without disassembling the circuit breaker components.

Abstract: A sealed contact unit that attains stabilized contact switching operation and effective dimensional minimization with an arrangement wherein a switching contact section including opposing movable and stationary contacting members is housed within a sealed container together with an electrically insulating gas, a movable shaft interlocked to the movable contacting member is hermetically passed through a wall of the container to be axially shiftable with an end projected externally while the movable contacting member biased away from the stationary contacting member by a resetting spring is mounted through a contact-pressure spring to the other end of the movable shaft inside the container, the contact-pressure spring being provided to coaxially enclose the movable shaft and biasing the movable contacting member against the biasing force of the resetting spring for attaining a contact-pressure when the movable contact member shifts to engage the stationary contact member fixed inside the container, a driving se

Abstract: A two-pole switch for DC current has a housing formed by a pair of open shells abutting each other to enclose components of the apparatus. Each shell rigidly holds a stationary contact, and an actuator is pivotally coupled to the shells. A pair of movable contacts are pivotally attached to the actuator so that each movable contact touches one stationary contact when the actuator is in a first position and the contacts are separated when the actuator is in a second position. A spine plate is between the shells and electrically separates the two stationary contacts and arc extinguishing chambers. A solenoid is within the housing aligned with the contacts and drives the actuator between the second and first positions to close the contacts.

Abstract: A housing is provided for a circuit breaker. The circuit breaker has contacts capable of being in an open state or a closed state, of movement between the open and closed states, and of generating a hot gas in consequence of that movement. An electronics module is provided for controlling movement of the contacts from the closed state to the open state. The housing has a first portion housing the contacts and a second portion housing the electronics module. The second portion is formed of a material subject to damage by the hot gas, and the first portion is constructed to protect the second portion from damage by the hot gas. The first portion is ideally formed of a thermosetting material resistant to damage by the hot gas and the second portion is ideally formed of a thermoplastic material, which reduces the cost of manufacturing the housing. A quick-mounting construction for assembling the second portion with the first portion further reduces the cost of assembly.

Abstract: A circuit breaker including a trip unit interlock. The trip unit interlock provides a trip unit having a plug connectable with a mating plug which is slidable with respect to the circuit breaker. The trip unit engages a pair of pins mounted to the circuit breaker when the trip unit is in its operating position. The pins are oriented to prevent separation of the plug from the receptacle during circuit breaker tripping. Since it is undesirable to insert a trip unit into a circuit breaker where the trip unit is not compatible with the circuit breaker, the pins and openings in the trip unit are configured such that they will not mate if the trip unit is not appropriate for the circuit breaker. When the trip unit is in its operating position, the trip unit holds an interlock lever for the contact operating mechanism of the circuit breaker in a position where the contact operating mechanism may close the contacts and hold the contacts closed when the circuit breaker is in its ON state.

Abstract: A latching block to be coupled to an electromagnetic switching device, which holds the switching device in the working position by locking the mechanism of the switching device which carries out the switching action. The latching block has a housing, a rack which can be coupled to the mechanism which carries out the switching action with a positive lock, and a lever which acts on a ratchet wheel. The engagement of the lever and the ratchet wheel can be released for unlocking.

Abstract: A molded case circuit breaker with interchangeable trip units has on its front face a frame protruding out from the front panel of the circuit breaker, and surrounding the circuit breaker operating handle. The frame has a window in which the end of a bracket support is inserted fixedly secured to the trip unit, when the latter is in place. An inscription, notably of the rating of the trip unit, is borne by a face of the bracket support so as to be visible at all times, even when a front protection plate covers the trip unit.

Abstract: An electromagnetic switching device comprises a housing containing a switch contact space and connection contact space, and a driving space formed by a basic body in which the magnet and coil are lodged. The parts of the connection contacts and coil connections of the pre-assembled contact carrier with return spring and of a switch space cover with an insertion device that can be releasably fastened to said cover, which are to be accommodated in the housing, are assembled in succession from a direction perpendicular to the sliding direction of the contact carrier and retained by interlocking connections.

Abstract: A protective switch device such as a relay switch includes at least one pole having at least one moving contact that cooperates with a stationary contact and a magnetic or thermal trip mechanism for assuring protection against overloads and excess currents and that acts on a control mechanism actuating the moving contact and that can be activated by a rotary control knob rotating about a pivot pin. Recocking of the control mechanism is possible from a "tripped" to an "off" or from a "tripped" to an "on" position. The control mechanism includes a lever for opening the contacts that pivots from an on position corresponding to the closing of the contacts to a position corresponding to the opening of the contacts. The opening lever is associated with a pivoting cocking mechanism, which is able to bring back and hold the opening lever in the on position. A trip mechanism is provided which is able to control the mechanical separation of the opening lever and the cocking mechanism so as to free the opening lever.

Abstract: A switch device using a main switch coupled to a monostable auxiliary switch through a releasable coupling is disclosed. In this device, the auxiliary switch and the main switch are closed in succession by simultaneous movement of their respective contact-holders and are opened in the reverse order by virtue of the presence of the releasable coupling which is released during closing and engaged during opening.

Abstract: A molded case multi-pole circuit breaker having an electronic trip unit to determine overcurrent conditions connects with a corresponding current transformer within each pole to sample circuit current. Upon the occurrence of an overcurrent condition, a trip actuator is energized to interrupt the circuit current. A current transformer adapter unit supports the trip actuator wire conductors and pin connectors while at the same time shielding the current transformers from the circuit breaker exhaust gases.

Abstract: An industrial rate multi-phase molded case circuit breaker is fitted with an exhaust gas barrier and line lug cover at the line end thereof to redirect the arc exhaust gases exiting from the line end. An electric circuit is prevented between the different phases of a multi-phase electric power distribution system connected with the line end of the circuit breaker. Furthermore, an electric circuit is further prevented between the exiting arc exhaust gases and the electrical distribution bus bars to which the multi-phase electric circuit breaker is connected.

Abstract: A modular low voltage multipole circuit breaker, including a plurality of identical single-pole breaking units each including a parallelipipedic insulating box having two opposite parallel large side faces and two opposite parallel small side faces, two terminals located at respective opposite parallel small side faces, a stationary contact electrically connected to one of the terminals, a movable contact cooperable between a first position contacting the stationary contact and a second position separated from the stationary contact and a molded case for housing the single-pole breaking units. The molded case has two opposite parallel side walls having the same thickness, the single-pole breaking units being sequentially arranged and parallel to each other and parallel to the side walls such that adjacent single-pole breaking units are spaced apart a distance equal to twice the thickness of the side walls, the single-pole breaking units being spaced apart at a constant pitch.

Abstract: A protective switch device such as a relay switch is provided with at least one pole having contacts that can be separated. It includes a control mechanism (5) that can cause the opening and closing of contacts (21, 31) and that can be actuated by a protective device (4) that can act in case of electrical failure, and a manual control button (6) controlling an electromagnet (7) for operating the contacts. A moving trap door (11) opens and closes an opening of the box so as to make it possible to change the coil of electromagnet (7). The trap door (11) cooperates with a trap door locking element (81) that can be displaced between a closed position where it immobilizes the trap door on the box and an open position making it possible to open the trap door.

Abstract: Apparatus is illustrated for positioning longitudinally spaced switches upon a base member which member may be the cylinder of a robotic control apparatus and which apparatus achieves a clamping action through the use of a rail (A), a locking bracket (B), a rocker arm (C) fixed upon the rail and an abutment (D) carrying a bearing member (E) forcing the bracket into engagement clamping both sides of the switch against the base member.

Abstract: An electromagnetic relay with a resistor is manufactured through the process comprising the steps of assembling an actuating part of the relay having a coil, contacts, terminals, an armature, a core and the like, setting the resistor on a base having slots to receive the terminals, and mounting the actuating part of the relay on the base by inserting the terminals into the slots of the base. The resistor is connected to coil terminals connected with the coil by fitting lead wires of the resistor into slits formed in the respective coil terminals so as to open in the inserting direction of the terminals at the same time of mounting the actuating part of the relay.

Abstract: A power switching module is adaptable for installation in a variety of existing circuit breaker panels. The module contains electrical controls providing selected control functions, such as an integral timer function. The module plugs into an existing breaker position in the circuit breaker panel adjacent a conventional circuit breaker on the same panel. The module has external terminals, including an interchangeable clip for connecting to the circuit breaker panel buss, a switched-circuit input series-connected to the load line output from the adjacent circuit breaker, a switched circuit output for carrying power to an external load being controlled by the switch, and a neutral wire extending to a neutral terminal on the panel. A microprocessor contained in the module provides the switched timer function that is set by digital inputs and displayed on the module housing. The microprocessor obtains operating power from the circuit breaker panel buss and controls operation of the switch solenoids.

Abstract: A modular crossbar arrangement for molded case circuit breakers allows a plurality of contact arm assemblies to be interconnected from a single modular unit. To provide increased acceleration to the movable contact arms a contact arm accelerator lever interfaces with the contact arm and crossbar assembly. To promote further acceleration of the movable contact arms to their closed positions, the movable contact arms in a multi-pole circuit breaker are staggered with respect to their rotational alignment within each pole on the crossbar assembly.

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 electromagnetic valve assembly having a valve unit with a valve seat and a coil arrangement. An armature is slidably disposed in the bore of the coil arrangement. A yoke unit surrounding the coil arrangement is in two parts having cooperating longitudinally extending edges forming two axially extending air gaps on diametrically opposite sides of the yoke unit. End flange portions of the two parts of the yoke unit are cut to form articulated tabs which facilitate the forming of the flange end portions.

Abstract: An electromagnetic contactor comprising a housing, the housing being adapted to receive internally thereof a stationary armature, a coil subassembly, return springs, and a block subassembly, the block subassembly comprising a block adapted to receive terminals and a carrier subassembly, the carrier subassembly comprising a carrier member adapted to receive and retain a movable armature, the housing having internally thereof a plurality of detents adapted to be overridden by the block subassembly and to snap over exposed surfaces of the block subassembly to lock the block subassembly, the stationary armature, and the coil assembly in the housing, whereby to complete assembly of the contactor without fasteners; and a method for making the contactor.

Abstract: Molded case circuit breaker having collapsible toggle linkage with rectangular cross section knee pin non-rotatably held within open rectangular slots in upper link, bifurcated movable contact fingers loosely guided for pivotal movement about fixed pin to break contact welds, helical compression springs biasing bifurcations against faces of a stationary connector, trapezoidal cross section shaft biasing shaft against a fixed corner of clamping strap and frame, increasing clamping force and increasing tool clearance, operating handle which changes pivot point moving to RESET position, reducing lateral force component of operating springs for reliable return of handle to OFF position, dual stops for movable contact fingers to spread impact forces along fingers, greater contact separation in poles not containing operating mechanism, slot motor laminations providing metal reinforcement to separate arc chamber housing which is cooperatively interlocked with base to distribute structural strength, terminal cover wi

Abstract: A unitary flexible substrate has three planar areas with components and conductors carried thereon. The substrate is folded to provide a subassembly with a compact packaging factor such that each planar area is in a different parallel plane. Two conductor-carrying projections of the substrate extend from different end portions of the substrate to free distal ends of the projections which are positioned adjacent to each other. The projection conductors, at the projection distal ends, are soldered to each other to provide a more direct, low resistance electrical connection between conductors on the substrate end portions. Heat sink rigidizer plates are attached to each of the three planar substrate portions. One rigidizer plate is thermally and planarly coupled to a metal heat sink cover of a protective housing for the folded subassembly. The other rigidizer plates are planarly bonded to each other to form a unitary support structure for two of the planar substrate portions.

Abstract: A current switching device comprises, in a box, at least one polar current path, disposed between two connecting terminals. The at least one polar current path comprising, in series, a break pole formed by at least one stationary contact and at least one mobile contact, a protective thermal tripping device having a bi-metal strip surrounded by a heater element and a protective magnetic tripping device having a coil wound around a coil form in which a mobile core slides. A wire of the coil being connected by an intermediate conductor to an end of the heater element. A wire of the heater element comprising a lower end which is substantially straight and without curvature, the lower end of the wire of the heater element being soldered to the intermediate conductor. The intermediate conductor being soldered to a substantially straight lower end of the coil wire. The two tripping devices being carried by a support which is slidably removable from the box.

Abstract: A polarized electromagnetic relay has two electromagnetic relay portions each constituted by a first yoke, second yoke, coil, movable core, card, and the like. The first yoke and the second yoke are used to flow a magnetic flux caused by a permanent magnet in the movable core in the same direction as a magnetic flux caused by the magnetization of the coil, and thus electrical power flowing in the magnetized coil can be small, or an area occupied by the coil can be small. Therefore, a small size and economical polarized electromagnetic relay having two groups of electromagnetic relays can be provided, and a stable operation regardless the states of magnetization or non-magnetization of one or both coils of the two electromagnetic relay portions can be realized.

Abstract: An overload relay includes a base (22) with electrical contacts (162, 164) thereon. A lever (116) including a contact actuator (140) is in proximity to the contacts (162, 164) and a pivot (122) mounts the lever (116) on the base (22) for pivotal movement between first and second positions. A releasable latch (106) normally holds the lever (116) in a particular one of the positions and a spring (144) is interposed between the base (22) and the lever (116) at a location spaced from the pivot (122) to bias the lever (116) toward the other of the positions by applying a bias thereto in a generally predetermined direction. The direction and location are such that when the lever (116) is in a latched position, the bias will provide a relatively small force tending to move the lever (116) toward the unlatched position and further is such that as the lever (116) moves towards the first position, the bias produces an increasing force tending to move the lever (116) towards the unlatched position.

Abstract: Molded case circuit breaker having collapsible toggle linkage with rectangular cross section knee pin non-rotatably held within open rectangular slots in upper link, bifurcated movable contact fingers loosely guided for pivotal movement about fixed pin to break contact welds, helical compression springs biasing bifurcations against faces of a stationary connector, trapezoidal cross section shaft biasing shaft against a fixed corner of clamping strap and frame, increasing clamping force and increasing tool clearance, operating handle which changes pivot point moving to RESET position, reducing lateral force component of operating springs for reliable return of handle to OFF position, dual stops for movable contact fingers to spread impact forces along fingers, greater contact separation in poles not containing operating mechanism, slot motor laminations providing metal reinforcement to separate arc chamber housing which is cooperatively interlocked with base to distribute structural strength, terminal cover wi

Abstract: A protective housing for enclosing a reed switch which includes an elongate hollow member having an opening at one end for access to a cavity inside the member. The cavity is sized to permit insertion of the reed switch inside the cavity. Fillant substantially closes the opening of the hollow member without making contact with the body of the reed switch. The fillant surrounds wires which are attached to the connecting leads of the reed switch. A method, which utilizes a blocking member, of enclosing a reed switch in a hollow member is also disclosed.

Abstract: A bell alarm unit is attached to the actuator-accessory unit of a molded case circuit breaker. The bell alarm unit consists of a microswitch, printed wire board connector and external wire conductors integrally encapsulated within a plastic composition to provide strain relief to the electrical connections between the printed wire board and the external wire conductors.

Abstract: Assembly of a remote controlled relay has steps of: previous assembling of units which are constituted by components having a concern with each other; positioning of the units on a base member; soldering of wires of electric components; coupling on the units which have mechanical concern; and covering of the units by a cover member which is fit and fixed to the base member.

Abstract: The plastic material used to form the case and cover of a molded case circuit breaker includes a filler material such as glass fibers for strength purposes. To insure that the incoming plastic material contains the requisite filler material, a fluorescent material is included with the filler. Illumination of the plastic material under ultra-violet light confirms the presence of the fluorescent material and the filler material prior to fabrication of the circuit breaker case and cover. Illumination of the circuit breaker under ultra-violet light in the field confirms both the presence of the filler material as well as the source of manufacture.

Abstract: The low dissipation compact circuit breaker of the present invention selectively conducts breaker current in a circuit to be protected. The compact circuit breaker is in an enclosure surrounding at least a stationary contact and a moveable contact. This moving contact selectively assumes one of two bistable states, a contiguous closed state or a noncontiguous open state. A rotary operator including rotary members and a contact lever train selectively causes the stationary contact and the moveable contact to assume either a closed or an open state. A single solenoid for sensing breaker current in each phase causes the rotary operator to move the contacts from a closed state to an open state. Additionally, the solenoid for a faulted phase directly acts on a solenoid bell crank to cause the contact to begin to assume an open state in a trip operation, if breaker current reaches a preselected trip value in the faulted phase.

Abstract: An industrial rated molded case circuit breaker fitted with an exhaust arc gas manifold arranged over ventilation slots of the circuit breaker and disposed at a line end thereof to redirect the arc exhaust gases exiting the ventilation slots. The exhaust arc gas manifold is fixedly attached to the circuit breaker to prevent an electric fault from occurring between the different phases of a multi-phase electric power distribution system connected to the line end of the circuit breaker. An electric fault is further prevented between the exiting arc gases and the line terminals attached to the circuit breaker thereof.

Abstract: A dust preventing device for an electromagnetic contactor prevents foreign matters accumulated on a foreign matter preventing wall from slipping off the wall due to vibrations of electromagnetic contactor. In a case where an arc extinguishing chamber cover is disposed to cover a fixed contact and a movable contact, and includes a foreign matter preventing wall provided under a gas discharging opening formed on the cover, the foreign matter preventing wall is formed with ribs provided therearound in a shape of an embankment. Therefore, foreign matters having entered through the gas discharging opening can be positively trapped in a hollow portion surrounded by ribs, so that the foreign matters do not fall into the electromagnetic contactor from the foreign matter preventing wall due to vibrations of the contactor.

Abstract: A protective switch device such as a contactor/circuit-breaker comprises double-contact switch poles. Contact bridges are housed in a mobile support. Slide members guided in slots of the support and commanded by a tripping mechanism can be applied to the bridges. The mobile support can be actuated by a solenoid without the contact pressure springs transmitting any reaction force to the armature of the solenoid.

Abstract: The present invention aims to provide a current-limiting circuit breaker which is improved in assembling efficiency and which can readily cope with diversification of specifications. The circuit breaker of the invention comprises power source side contact unit including a group of component parts containing a power source side contact and movable contact unit including a group of component parts containing a load side contact. The units are detachably connected to each other. The movable unit is selectively connected to the various power source side contact units. Therefore, according to the invention, circuit breakers of various kinds of types can be obtained which are more useful, and manufactured by a small number of component parts some of which are commonly used in products. The circuit breakers can readily cope with the diversification of the specifications, and are improved in assembling efficiency.