Eaton Corporation

Westinghouse Electric Corporation

Yun-Ko N Chien

John Joseph Shea

Paul Richard Rakus

John A Wafer

Michael B Schulman

Thomas Clements Pendrick

Glen C Sisson

Jeffrey A Miller

Alfred E Maier

William E Beatty, Jr

Douglas Charles Marks

Walter V Bratkowski

Ronald W Crookston

Ralph Mason Ennis

James Alan Trax

Richard E White

Andrew James Male

John G Salvati

Steven Castelein

Edmond F Kowal

Norman L Ovick

A current limiting power switch has a monolithic stationary conductor with a conductor section that mounts fixed contacts that engage moving contacts on moving contact fingers to form a reverse current loop with the contacts closed. A terminal section projects transversely from one end of the conductor section and an arc runner section extends from the other end. The tapered arc runner has a generally laterally centered tapered area that gathers the arcs and urges them along a raised rib on the arc runner to an arc chute. A reinforcing rib running from the back of the conductor and arc runner sections to the terminal section resists distortion of the monolithic stationary conductor by the high temperatures and closing and electromagnetic forces during interruption.

Monolithic stationary conductor and current limiting power switch incorporating same

A moving contact assembly for a high-current interruption electric power switching apparatus has an inner carrier for the contact fingers that is rigidly held in a withstand position in an outer carrier by a spring biased cam follower pin engaging a cam profile on the inner carrier and configured to positively seat an inner carrier stop against an outer carrier stop on the outer carrier and to rapidly drive the inner carrier to a blow open position in response to a fault. The cam profile has an extended width divided between spaced apart cam profile sections to absorb the high closing and withstand forces. An abutment on the outer carrier resists bowing of the cam follower pin between the cam profile sections. Complementary convex and concave partial cylindrical surfaces on the inner carrier and a gas shield on the moving assembly carrier body maintain an arc gas seal during blow open.

Blow open moving contact assembly for electric power switching apparatus with a very high current interruption rating

A shorting switch eliminates arcing faults in power distribution equipment. The shorting switch includes an insulating tubular housing; a first contact; a second contact; and an insulator between the first and second contacts in the insulating housing. The insulator prevents electrical connection of the first and second contacts. First and second terminals are respectively electrically connected to the first and second contacts. A wave spring mechanism moves the first and second contacts toward closure. A slug and an activated charge mechanism drive the insulator from between the first and second contacts, in order to electrically connect the first and second contacts.

Shorting switch and system to eliminate arcing faults in power distribution equipment

A current throttle resistor external to a contactor device protects an electrical power distribution circuit coupling a load to a power line. The contactor has electrical switching contacts in series with the load and the line, and for example, an electromagnetically controllable switch for opening the contacts. A current sensor is coupled to the controllable switch for opening of the contacts upon occurrence of a high current fault in the power distribution circuit exceeding a predetermined threshold. A resistive element in series with the power distribution circuit between the line and the load, provides a voltage drop for limiting current during the high current fault. The resistive element can be a nichrome strip or similar positive temperature coefficient resistance having a low cool resistance, and is thermally isolated from the controllable switch by mounting in a resistor housing external to the contactor. To maximize resistance and minimize space, the nichrome strip is bent in an elliptical arc between two leads that protrude from the resistor housing, for coupling into the circuit on the load side of the contactor.

Three phase throttle current technique

A circuit breaker having electrical contacts operable between a closed position in which a circuit is completed through the conductor and an open position in which the circuit through the conductor is interrupted. The circuit breaker includes a latchable operating mechanism operable to open the electrical contacts when unlatched and a trip bar rotatable from a biased position to a trip position to unlatch the operating mechanism. A magnetic trip assembly is provided including a frame, a stationary magnetic structure mounted to the frame and a movable armature which is attracted to the stationary magnetic structure by abnormal current through the conductor to rotate the trip bar to a trip position. The movable armature includes a nib extending angularly therefrom, the nib defining a detent. The armature is pivotably mounted to the stationary magnetic frame by a pin. A spring biased plunger supported by the frame engages into the detent to bias the armature away from the stationary magnetic structure to form a gap therebetween. The plunger disengages from the detent when the armature is attracted to the stationary magnetic structure by the abnormal current through the conductor to allow the movable armature to rotate about the pin and trip the trip bar to interrupt the circuit.

Circuit breaker

A molded case circuit breaker having current limiting capabilities optimized for relatively smaller frame sizes. More specifically, one aspect of the invention relates to a two-piece carrier assembly for carrying the main and arcing contact arms which allows the main and arcing contacts to be blown open during short circuit conditions. The two-piece carrier assembly includes an inner carrier and an outer carrier pivotally connected together. The contact arms are carried by the inner carrier. When sufficient magnetic repulsion forces are exerted on the contacts due to a short circuit condition, the inner carrier pivots relative to the outer carrier to allow the contact arms to blow open. In order to control the amount of force required for blow open, a compression spring loaded cam assembly is provided. Another important aspect of the invention relates to a contact spring housing which relocates the contact springs away from the separable contacts to protect the springs from damage, for example, from heat due to contact separation. In order to improve the interruption time of the circuit breaker for relatively large overcurrents, such as a short circuit, a reverse current loop is provided which generates sufficient magnetic repulsion forces to blow open the separable contacts in a relatively short period of time. Within the restraints of the physical dimension of a relatively smaller breaker frame size, additional features have also been incorporated. More specifically, an improved rating plug assembly is provided with a one-piece plunger, relatively easier to manufacture than known designs which utilize two-piece plungers. Another aspect of the invention relates to an auxiliary cam plate for controlling the motion of the crossbar at the remote end in a four pole circuit breaker. The cam plate compensates for bending of the crossbar to improve the contact force in the remote pole. Lastly, a molded interphase barrier forms a gas barrier within the circuit breaker and maintains its position during assembly relatively better than known interphase barriers.

Molded case current limiting circuit breaker

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.

Miniature circuit breaker

A current limiting circuit breaker characterized by pairs of stationary and movable contacts with the movable contacts connected in series; an arc-extinguishing chamber including arc guide rails associated with each pair of contacts and in side-by-side relationship; manually operable means for opening and closing the circuit through the contacts; current-limiting electromagnetic means for opening the contact; and linkage means between the manually operable and electromagnetic means for enabling opening of the contacts by the electromagnetic means without tripping the manually operable means.

Current limiting circuit breaker with series double break contact system

A current limiting solenoid operated circuit breaker characterized by an arc quenching chamber having spaced arc guide rails along opposite sides of the chamber, stationary and movable contacts in an arcing zone adjacent to the chamber and electrically connected to corresponding guide rails, and a conductor around the arcing zone to generate a transverse magnetic field through an arc to drive the arc from the contacts and along the guide rails to the arc quenching chamber.

Growing community of inventors

Pittsburgh, PA, United States of America

Yun-Ko N Chien