Abstract: A bridging contact is arranged across two fixed contacts with a pair of parallel, closely spaced conductors serving as the bridging contact carrier. A high current pulse in opposite direction within the parallel conductors generates electrodynamic forces rapidly propelling the conductors further apart. The bridging contact carried by the parallel conductors is rapidly driven out of contact relation with the fixed contacts to interrupt the circuit.

Abstract: A contact assembly for electrical circuit breakers has a contact lever and a lever support with the contact lever mounted thereon in an articulate fashion. The support lever is flexibly positioned around a fixed pivot bearing by a drive linkage device for on- and off-switching cycles. A pressure lever is used to introduce a current-dependent force onto the contact levers in order to increase the contact force. The pressure lever is similarly flexibly mounted onto the lever support. The contact lever and the pressure lever operate jointly via their working surfaces which permit a conveyance of force in terms of an increase of the contact force. When switching on the contact assembly, the pressure lever is decoupled from the contact lever so that the tendency to bounce is reduced.

Abstract: Individual movable contactors of a circuit breaker are made up of a pair of conductors. The first conductor has one end bifurcated to form a pair of legs separated by a slit. At the open end each leg has a curved inner portion the opposed curved portions of the two legs defining a receptor space which is substantially circular in cross section. The second conductor has one end whose cross section is substantially circular and which fits within the receptor space and makes a good slidable contact therewith, and the other end which supports the main contact. Provision is made for rotating the second conductor about its circular end for opening or closing connection to the main contact.

Abstract: The electromagnetic forces tending to force open the contacts of an electromagnetic contactor are reduced by providing a current flow path having a geometry that tends to minimize the magnetically produced forces acting upon the movable contact of an electromagnetic contactor. A contactor has a frame, a stationary contact attached to the frame, a first conductor supplying the stationary contact, an armature rotatably mounted in the frame, a movable contact attached to the armature, and a second conductor supplying the movable contact. An arm has a first arm end supporting the movable contact and a second arm end attached to the armature.

Abstract: An electro-mechanical circuit breaker device incorporating a fuse cartridge, wherein two contact bars are normally connected by a series of mobile contacts held against their lower edge by springs, two in number for each. An insulating plate, suitably guided at its edges in the insulating envelope of the apparatus, receives the downward displacement that a coil applies by the Thomson effect to an aluminum disc, and it lowers the contacts against spring and latches them in open position by engagement of a bolt in a notch. The lower edge of the plate is provided with teeth to receive the successive contacts and retain them transversely, while each of the mobile contacts is notched to ensure lengthwise retention.

Abstract: A movable contact arm assembly is provided for a circuit breaker. The contact assembly includes a carrier which has first and second guide plates with aligned roller guides and bracket supports and a roller which has a middle portion extending between the guide plates and the end portions and engaging the roller guides. A bracket extends between the guide plates and engages the bracket supports. A spring is positioned between the bracket and roller which urges the roller along the roller guide. The contact arm has first and second cam surfaces and is positioned between the guide plates and pivotally connected thereto. The roller rides in the guide on the first and second cam surfaces and the roller moves from the first cam surface to the second cam surface as the contact arm moves from a closed position to an open position in response to preselected electromagnetic repulsion forces.

Abstract: A contact that has two fixed contact elements and a mobile contact bridge actuated by a switching assembly and is urged by a pole spring. The connection between the mobile contact bridge and switching assembly is provided by a magnetic compensator connected to the switching assembly by means of a magnetic coupling device adapted so that, when the compensating forces rise above a given threshold, the magnetic compensator is disengaged from the switching assembly and becomes inoperative.

Abstract: An electric circuit breaker having fast short circuit response along with reduced arc energy is provided by means of a current limiting contact arm arrangement. The contact arm is arranged to pivot independently of the circuit breaker operating mechanism under the influence of magnetic repulsion forces. A contact spring configuration controls the rate at which the contacts separate, thereby limiting the energy of the arc created upon contact separation.

Abstract: A current-limiting electric switch for low-voltage has a contact device with a contact finger and an elongated fixed contact arranged side by side. The contact finger is rotatably arranged and forms at one end a break together with the fixed contact and is at the other end provided with a flexible current connection conductor. The contact finger has its bearing point located between the two ends of a movable arm. Through the influence of electrodynamic forces from short-circuit currents, the contact finger is first rotated in one direction of rotation while maintaining the galvanic contact at the break, whereby the movable arm is displaced so that the distance between the bearing point of the contact finger and the fixed contact is increased. A stop means limits the movement of the contact finger in the first direction of rotation and brings about a continuation of the rotational movement in the opposite direction of rotation resulting in an instantaneous contact opening.

Abstract: A device is provided comprising a simple means for holding the contacts apart and insulated from each other after circuit breaking.A screen formed by an insulating plate of small thickness, is placed between two mobile contact levers and is urged by springs against flanges which are integral with the levers and which move apart when short circuit currents appear for allowing this screen to be rapidly projected between the contact inserts.This simple circuit-breaker device may be used such as it is or in association with a contactor for protecting lines which supply consumer apparatus.

Abstract: An apparatus comprising a plurality of circuit breakers with a rigid contact bridge 16 cooperating with fixed contacts 9, 10 carried respectively by conductors 11, 12, generating repellent forces; the median region 21 of the bridge cooperates with a magnetic structure 37 providing the bridge with compensation forces for the contact pressure when the latter is under a predetermined threshold, above which the bridge is ejected from the fixed contacts. This contactor is advantageously used for the control of power consuming apparatus and protection of their supply lines.

Abstract: A fast opening contactor comprising an electrodynamic repulsion trip device associated to a standard contactor unit so as to operate the contacts towards the open position against the electromagnetic attraction force in response of a short-circuit current.

Abstract: An electrodynamic operating mechanism is connected to a vacuum interrupter to produce an interrupter with a switching time of about one millisecond. Magnetic latch means are provided to hold the contacts open after interrupter operation.

Abstract: A high speed actuating mechanism for operating the contacts of a circuit interrupter has an operating shaft connected to the contacts and to an operating piston. The operating piston has a short-circuited conductive ring or repulsion disc which is closely coupled to a lenz coil operator in one position of the actuating mechanism. The operating piston also has an enlarged diameter sealing protrusion which seals against an annular seal which is concentric with the lenz coil operator. Both the lenz coil and the sealing ring are spring-mounted to have several degrees of resiliency to enable proper relative location of the repulsion disc and the lenz coil and proper relative location of the annular seal and contact protrusion to control seal penetration and to enable compensation for contact erosion when butt-type contacts are used.

Abstract: A resettable high-voltage fusing device including a vacuum interrupter and an arrangement of magnetically displaceable rod members which are displaced by the magnetic forces resulting from overload currents flowing through them. For currents below the "blow" rating, a spring arrangement keeps the rods in place by applying axially opposing forces at the ends thereof, and the vacuum interrupter is kept closed. After rod displacement caused by overload current the vacuum interrupter opens in response to one of the springs released by displacement of the rods.

Abstract: An electric circuit breaker comprises first and second contacts, which engage each other while the circuit breaker is fully closed and both of which are movable. During the initial portion of an opening operation, the two contacts move together and remain engaged. First electromagnetic-assist means develops while the contacts are engaged a magnetic force on the first contact varying directly with current through the contacts which urges the first contact toward the second contact. Second electromagnetic-assist means develops while the contacts are engaged a magnetic force on the second contact varying directly with current through the contacts which urges the second contact toward the first contact. Means is provided to block motion of the first contact with the second contact after initial opening motion of the second contact and to prevent during subsequent opening motion of the second contact the transmission of force from the first electromagnetic-assist means to the second contact.

Abstract: A current limiter providing for a rapid triple series break in the protected circuit. Two movable contact arms are electromagnetically driven apart by two electromagnetic or slot motor drives for rapid circuit interruption when current through the current limiter exceeds a predetermined value. This provides twice the rate of contact separation than that which can be obtained from a single contact arm and consequently increases the rate of arc voltage rise and reduces peak let through current. The magnetic drive devices are formed from a ferromagnetic material and have a narrow slot formed therein, which is magnetically open on one end. Each contact arm is disposed in the slot of an associated magnetic drive device near the open end thereof. Each movable contact arm has a pair of spaced apart contacts mounted thereon. One of these contacts engages a stationary contact and the other contact engages a mating contact on the opposing movable contact arm when the current limiter is closed.

Abstract: This circuit breaker comprises closing-assist means for opposing the contact-repulsion forces developed when a high current flows through the circuit breaker. This closing-assist means comprises spaced segments of high permeability material fixed to opposite sides of the usual movable contact rod and projecting laterally therefrom. Two stationary bridging members of high permeability material are located at opposite sides of said contact rod, and each extends between said segments when the contacts are engaged. The segments are located in proximity to but slightly spaced from the bridging members when the contacts are engaged so that said bridging members and said segments define a high permeability path around the contact rod containing short gaps between said segments and said bridging members.

Abstract: This electric circuit breaker contains electromagnetic-assist means for opposing the contact-repulsion forces developed when a high current flows through the breaker. The assist means comprises a rigid supporting member which can be restrained in a fixed position to render the assist means capable of transmitting closing force to the movable contact of the breaker but which supporting member is releasable to render said assist means generally ineffective to transmit closing force to said movable contact. The assist means further comprises a toggle connected between the supporting member and the movable contact for imparting a closing force to the movable contact when forced toward an in-line position while said supporting member is restrained.For forcing the toggle toward its in-line position, there is provided magnetic structure cooperating with a conductor connected in series with the circuit breaker contacts.

Abstract: Circuit interrupter having a magnetic circuit energized by the current flowing through the interrupter and an induction plate that is movable with the movable contact of the interrupter. The abrupt rising of a fault current induces secondary currents in the induction plate which is located in the air gap of the magnetic circuit as long as the interrupter is in the closed-circuit position. The secondary currents tend to expel the induction plate from the air gap thereby moving the movable contact vigorously away from the magnetic circuit.

Abstract: A circuit interrupter protective device characterized by a two-level current limiting structure which provides current limiting on the main or supply side of the current limiter to one level of the peak let through current and to a much lower level on the load side which is achieved by activating a short circuit in parallel with the load by closing a set of shunt contacts the instant the current limiter begins to operate while the current limiter remains in the supply circuit to continue opening the circuit and dissipating the energy of an arc in deion plates.

Abstract: In order to eliminate contact bounce and electrodynamic repulsive forces upon closure in a standard high rating circuit breaker device when a fault exists, an armature is disposed on the movable contact assembly and an iron core pole is disposed adjacent the stationary contacts, the normal current path providing a partial turn about the core. As current passes through the contact assembly the resulting magnetic field attracts the armature and hence the movable contact assembly toward the stationary contacts.

Abstract: A current limiting circuit breaker having for each pole, a pair of main contacts separable upon operation of a thermally and electromagnetically operable tripping device and a pair of auxiliary contacts for current limiting in series with the main contacts and in parallel with a transformable resistor having a positive temperature coefficient of resistance. The auxiliary contacts are separable when an electromagnet is energized by a fault current which simultaneously energizes a field magnet to produce a transverse magnetic field across the auxiliary contacts and the arc formed between them when separating. This simultaneous action of electromagnet and field magnet coacting for rapid contact separation and lengthening of the arc upon flow of a fault current serves to increase arc voltage almost instantaneously to that of the source, about which time the fault current is totally shunted into the resistor.

Abstract: Current limiting circuit breaker having for each pole, a pair of main contacts separable upon operation of a thermally and electromagnetically operable tripping device and a pair of auxiliary contacts for current limiting in series with the main contacts and in parallel with a transformable resistor having a positive temperature coefficient of resistance. The auxiliary contacts are separable when an electromagnet is energized by a fault current which simultaneously energizes a field magnet to produce a transverse magnetic field across the auxiliary contacts and the arc formed between them when separating. This simultaneous action of electromagnet and field magnet coacting for rapid contact separation and lengthening of the arc upon flow of a fault current serves to increase arc voltage almost instantaneously to that of the source, about which time the fault current is totally shunted into the resistor.