Abstract: A low resistance electrical connecting assembly, each assembly including a plurality of operably arranged conductive elements, each element comprising a pair of relatively narrow, thin, outwardly convex, conducting contact surfaces supported on opposite sides of a latitudinal plane between them. The outwardly convex contact surfaces of each element are conductively associated to provide parallel current paths between source-side and load-side conductors in contact respectivley with opposite ones of said conductive surfaces of each element. Such elements may be embodied in the form of a helical coil of conductive wire, each ring of the coil constituting one element. Another embodiment may be individual disks of conductive metal arranged in stacking relationship. Any number of other embodiments are possible which provide a plurality of elements as described, thin, outwardly convex conductive surfaces on opposite sides of a latitudinal plane, in closely adjacent side by side arrangement.

Abstract: A proximity switch including a base assembly rotatably carries a sensing head formed of a support part rotatable about one axis extending through a base assembly for positioning a sensing face on a complementary sensing part in any one of four planes parallel to the one axis. A pivot between for the support and sensing parts enable the sensing face to be placed in a plane transverse to the one axis by rotation about a second axis at 45.degree. to the one axis. Flexible connections extend along the one axis and stops between the sensing and support parts avoid undue twisting of the connections. An annular printed circuit board supported by the base assembly and a plurality of fine wires carried on an elastomeric member supported in the support part provides separable multiple connections between each conductor on the board and the flexible connections.

Abstract: Arc suppressor plates in a high amperage molded case circuit breaker are arranged in an arc corresponding to blade travel and define passageways having larger exits aligned with respective vents defined by a molded insulator engaged in the wall of the circuit breaker base.

Abstract: A desensitizing circuit for the electronic fault sensing system of high amperage molded case circuit breaker to prevent a ground fault signal from tripping the breaker in the event of current transformer saturation or the response of a downstream breaker to the ground fault signal.

Abstract: A pair of toggle links in a high amperage molded case circuit breaker are driven over center in response to the discharge of a closing spring for pivoting a plurality of blades and closing the breaker contacts. A latch link pivotally connected to the upper toggle link also is engaged by a pivotable latch along an arcuate surface on the latch so that shock forces are transmitted along a radial line of the latch for minimizing inadvertent rotational forces on the latch. The latch release force is rendered dependent on the spring force exerted through the links from the blade overtravel springs and the coefficient of friction of the latch arcuate surface. The force exerted through the links is controlled by an adjustable stop having an inclined surface engaging the pivot connection between the toggle links. Large movements of the stop provide small changes in the inclined surface position relative the pivot connection to provide small changes in the overcenter position.

Abstract: An interlock assembly for a high amperage molded case circuit breaker is provided with a slide biased to interfere with movement of a push to close link whose operation enables discharge of the breaker closing spring. The slide is operated by the toggle assembly in the event the contacts are open to permit operation of the link except if the breaker is being tripped or held tripped. A trip solenoid of the permanent magnet type is reset, when tripped, by a reset spring under control of blade carrier which has excess energy available.

Abstract: A high amperage molded case circuit breaker utilizing a ratchet adapted to be operated manually or electrically and carrying a spring biased clutch connecting the ratchet to a crank for rotating the crank to tense a helical closing spring. The ratchet is disconnected from the crank when the closing spring has a predetermined tension by a crank operated trip assembly while the closing spring axis passes close to the crank axis to exert a relatively low torque on the crank. The crank rotates a handle positioner to prevent manual operation of the ratchet after the spring is tensed, while electrical operation of the ratchet continues until a switch located in any one of a large variety of positions terminates electrical operation.

Abstract: Arc control in a high amperage molded case circuit breaker is provided by a steel horn for each of a plurality of contact blades for each phase. The horn has a portion extending into a U-shaped recess in a steel arc runner plate. As the contacts separate, the portion travels close to one wall of the recess and then close to the other wall to transfer the arc from the contacts first to the one wall and then to the other wall which is located adjacent the arc suppressor assembly. A respective adjustment member extending through each horn controls the spacing between the blades and a contact carrier to in turn control the opening sequence of the contacts for minimizing arcing across certain contacts. Arc suppressor plates of alternating length are arranged in an arc corresponding to blade travel and define passageways having their larger exits aligned with respective vents defined by a molded insulator engaged in the wall of the base.

Abstract: An electronic system for a high amperage molded case circuit breaker employing a voltage to frequency converter circuit for transforming fault current levels to a number of pulses corresponding to the fault level. The pulses are applied to a long time delay and short time delay circuit respectively which integrates the pulses to provide an output in a time period inversely proportional to the fault level. The long time circuit is provided with a second stage activated for a selected time by each output of the respective first stage to further count the pulses and provide a long time delay output in a time period inversely proportional to the square of the fault current. A variable resistance power supply provides a fixed voltage drop across the current transformer output to facilitate changes in breaker rating with a simple rating resistor change. A bimetal switch is also employed to sense the temperature adjacent the breaker contacts.

Abstract: Trip indicator electromagnets of the permanent magnet type for use in a high amperage molded case circuit breaker under control of the long time delay and the short time delay or instantaneous circuits respectively for indicating the nature of a fault current and which can be reset by operating a viewing window that renders the indicator visible in response to armature movement.

Abstract: An interlock assembly for preventing two electrical control devices from simultaneously assuming a closed or "ON" position. The assembly comprises two subassemblies which are operably connected by a push/pull flexible cable. Each subassembly includes a frame member which carries a reciprocally movable plunger unit. A stop link is pivotally connected to the plunger unit at one end and carries a guide rod at its opposite end. The guide rod is retained within a guideway formed in the frame member which has a main longitudinally extending portion and an offset portion. The plunger unit is prevented from reciprocal movement to a depressed position when the guide rod is in the offset portion whereas reciprocal movement of the plunger unit to a depressed position is permitted when the guide rod is in the main portion of the guideway.

Abstract: The following specification describes a circuit breaker having a handle pivoted about an axis transverse to the axis of blade rotation for controlling an operating assembly to pivot a cam about an axis parallel to the blade axis to open or close the breaker contacts. The operating assembly is located in the center compartment of the breaker while the contacts and blades are located in end compartments of the breaker, and when the blades are moved past a predetermined position, they are then independently moved by a respective snap acting spring. Sensing means control the operating assembly in the event of a fault current to move to a trip position and open the contacts while providing a visual signal of the trip condition. Arc gases are vented to prevent engagement with the copper conductor connected to each contact and a stainless steel blade bracket is interposed between the movable contact and the copper blade to prevent an arc from contacting the copper blade.

Abstract: A multipole circuit breaker having a housing with a top wall center recess receiving a center strut of an interior trim. An operating assembly is interconnected with a trip assembly through a transistor link passing beneath the center recess and is operable by the magnetic assembly to assist the operating assembly in separating the breaker contacts in response to a fault current. A closure member overlapped by the interior trim prevents access to the load wires. A voltage reject configuration is provided on the housing to prevent mounting in a panelboard designed to carry voltages higher than that for which the circuit breaker is rated and a jaw assembly for the breaker is disclosed having a plurality of contact positions with each leg of a U shaped bus stab.

Abstract: An arc chute for a high voltage load interrupter switch has a pair of closely spaced side walls defining an arc chamber. An inner side of each wall has at least one groove between an open outer end of the chamber and an inner area of the chamber where blade contact is first broken resulting in a electrical arc. The longer axes of the grooves are generally perpendicular to the direction of flow of expanding arc gases that form at an inner end of the chamber when the switch is opened under load. The grooves have a semi-teardrop shaped cross section with the deeper portions of the grooves nearer the outer end of the chamber. As the expanding arc gases flow toward the chamber opening, some gas flows into the grooves which function as vortex generators causing the gases to swirl.

Abstract: A gangable wireway assembly including a plurality of generally U-shaped troughs and trough covers utilized as either tandem sections or as fittings which connect the tandem sections in an elbow, tee or cross configuration. Trough covers have upstanding lips at opposite ends and drip hood flanges running along longitudinal margins which overlap flanges on the U-shaped trough. The tandem section covers include a reverse bend on one drip hood flange to interlock one margin of the cover with the trough. Adjacent trough ends are nestingly received by a connector and adjacent trough covers are overlapped by a connector cover at the juncture of adjacent cover sections. The connector cover includes a recess receiving the lips of adjacent covers and includes flanges in overlapping relationship with the drip hood flanges. One flange on the connector cover also includes a reverse bend to interlock with the associated drip hood flanges.

Abstract: A screw orienting assembly in which slotted headless screws are sequentially fed with their elongate axis perpendicular to and in the same plane as a guide rail having a width less than the width of the screw slots. The screws are rotated about their elongate axis and advanced along the rail. The slots of those screws having their slotted end engaged with the rail become engaged with the rail in response to the rotation of those screws such that the slot is in alignment with the rail. The slot-engaged or "seated" screws are advanced along the rail to a predetermined point and discharged therefrom in like orientation with respect to their slotted ends for further processing. Those screws not seated on the rail are discharged from the rail before reaching the predetermined point.

Abstract: An electric circuit breaker including a U-shaped bimetal operably associated with a trip crossbar to effect rotation of the crossbar and subsequent opening of breaker contacts in response to heating of the bimetal to a predetermined temperature by the passage of an electrical current of a selected magnitude therethrough. The bimetal provides self-contained adjustment through the use of a calibration screw threaded into the lower leg of the bimetal which exerts force through an insulating member to the upper leg of the bimetal permitting ready calibration of the bimetal according to ampere rating of the particular circuit breaker.

Abstract: A multipole circuit breaker having a housing with a top wall center recess receiving a center strut of an interior trim. An operating assembly is interconnected with a trip assembly through a translator link passing beneath the center recess and is operable by the magnetic assembly to assist the operating assembly in separating the breaker contacts in response to a fault current. A closure member overlapped by the interior trim prevents access to the load wires. A voltage reject configuration is provided on the housing to prevent mounting in a panelboard designed to carry voltages higher than that for which the circuit breaker is rated and a jaw assembly for the breaker is disclosed having a plurality of contact positions with each leg of a U shaped bus stab.

Abstract: The following specification describes a fusible switch assembly having a thermoplastic base supporting a plurality of pivotal knife blades. A one piece thermoplastic arc suppressor housing common to a plurality of phases is also described together with arc suppressor plates snap fit in the housing and a common one piece thermoplastic rotor for moving the blades. The rotor is retained by engagement with the knife blades and walls of the base.

Abstract: The following specification describes a panelboard assembly comprising a plurality of modular insulators having spaced integrally formed resilient mounting rails for supporting a circuit breaker housing above the panelboard bus bars. Each circuit breaker is connected to a bar carrying current of one phase and on tripping may generate ionized arc gases that exit the arc chute passage and engage a bus bar carrying current of another phase. A thermoplastic insulating material is interposed in the path between the arc chute passage and a bus bar carrying current of another phase. A bend is also introduced in the bus bars intermediate their ends to force an insulating member interposed between the bus bars and a cabinet wall against the cabinet wall.