Abstract: A circuit breaker includes separable contacts for movement between a closed position and an open position to switch electrical current. An operating mechanism moves the separable contacts between the closed and open positions. A sensor senses the electrical current and outputs a sensed current signal corresponding to the electrical current. A shunt shunts a portion of the electrical current. A trip mechanism employs the sensed current signal to produce a trip signal. A trip actuator trips the operating mechanism to move the separable contacts to the open position. The trip actuator includes a trip solenoid having a coil energized by the trip signal and also includes one or more loops energized by the shunted portion of the electrical current.

Abstract: An integral electrical circuit controller apparatus selectively connects a load to a power source and includes an electrical contactor having contacts, a circuit breaker having separable contacts connected in series with the electrical contactor and a trip mechanism responsive to current flowing through the separable contacts for tripping the contacts open in response to predetermined current conditions, and a current throttle impedance for limiting short circuit current. The trip mechanism and the electrical contactor independently interrupt current flowing through the electrical contactor and the circuit breaker. The current throttle impedance limits short circuit current flowing through the electrical contactor and the circuit breaker until current is interrupted. The electrical contactor may include an overload relay. The current throttle may include a coiled conductor of nichrome or iron wire enclosed in a dielectric housing.

Abstract: A springclip for use on a changa lever of a latchable operating mechanism in a circuit breaker. The springclip is attached to the changa lever to dampen vibration thereof so that undesired disengagement of the changa lever from the projection of a trip bar of the circuit breaker is resisted.

Abstract: A circuit breaker with improved magnetic trip assembly includes electrical contacts operable between a closed position in which a circuit is completed and an open position in which the circuit is interrupted, 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. The circuit breaker further includes a magnetic trip assembly comprising a stationary magnetic structure, a movable armature which is attracted to the stationary magnetic structure by an abnormal current through the conductor to rotate the trip bar to the trip position and a plate means mounted to the movable armature and disposed between the armature and the stationary magnetic structure. The plate means adjusts the amount of abnormal current required to attract the movable armature to the stationary magnetic structure and in turn rotate the trip bar.

Abstract: A remotely positioned rotary operator handle for cooperating with a circuit breaker with a linearly movable handle. A housing is mounted over the circuit breaker handle. Within the housing a slide carrying a rack engages the circuit breaker handle which further engages a pinion gear sector mounted on a rotatable shaft. The rotatable shaft extends from the housing and has positioned thereon a motion translating device which translates between rotational motion and linear motion. The rotary handle extends from a housing which is flange mounted on a cabinet in which the circuit breaker is disposed. A corresponding motion translating device is attached to the flange mounted rotary handle which is in turn connected to the motion translating device attached to the rotatable shaft. The connection between the motion translators comprises a linearly moving link. The rotary handle has an extendable hasp which comprises part of the connection between the rotatory handle and the motion translating device.

Abstract: A circuit interrupter characterized by a movable contact on a contact-carrying arm movable between open and closed positions of a stationary contact mounted on one leg of a U-shaped conductor with another leg secured to the circuit breaker housing with a current throttling resistive element being disposed within the U-shaped conductive element for limiting the amount of fault let through current.

Abstract: A rotary handle operator for a circuit breaker with a linearly movable handle has a housing which is mounted over the circuit breaker handle. A slide carrying a rack engages the circuit breaker handle and is slidable within a chamber in the housing. The rack engages a pinion gear sector mounted on a rotatable shaft which extends through a cover on the housing. A rotating handle mounted on the shaft is rotated to linearly operate the circuit breaker handle or is positioned thereby when the circuit breaker trips. The handle may be locked in the off position by inserting the shackle of a lock through an aperture in a lever arm on the rotating handle to urge a pin on a spring biased locking piece within the handle lever into an aperture in the housing cover, or the shackles of several locks may engage a slot in a shroud surrounding the rotating handle to interfere with rotation of the handle out of the off position.

Abstract: A multipole circuit breaker, for example, a three pole circuit breaker, can detect a condition when less than all of the phases are open circuited to trip the circuit breaker. This reduces the tripping time and hence risk of damage to the electrical load. The circuit breaker includes a thermal trip unit and a phase sensitivity assembly that is interlocked with the bimetals included with the thermal unit. The phase sensitivity assembly includes one or more levers, responsive to the deflection of a bimetal corresponding to the open circuited phase resulting from cooling action of a bimetal relative to the other bimetals. The relative displacement of the cooling bimetal is used to either trip or reduce the tripping time of the circuit breaker.

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: A circuit breaker embodies with a single electromagnetically actuated plunger two levels of actuation, corresponding to two levels of excessive current or voltage defined by two different airgaps, one at the lower level for triggering the toggle mechanism, the other at the higher level for directly actuating the movable arm through a kicker arm. The preferred embodiment provides a double-ended lever pulled by the plunger at midpoint for actuating the trip bar, and the kicker arm is actuated in an overriding situation by the lever rotating about the trip bar blocked at the end of its initial move.

Abstract: A clip-connected terminal conductor uses a terminal lug for tightening together with a screw the line cable and the conductor end. A channel is provided in the lug for inserting therein, and guided by lateral wall of the channel, a spring-like member having centrally a boss which engages the aperture of the conductor end. The spring-like member has opposite ledges for clipping with the front and the rear edge of the base of the lug and channel.

Abstract: A power drive mechanism for a circuit breaker handle which includes a reversible electrical motor, a carriage assembly and a cooperating slide plate assembly mechanically coupled to the motor shaft. The carriage assembly includes a pivotally mounted L-shaped lever, interlocked with the circuit breaker operating handle for driving the operating handle to an on position or alternatively to an off position on command. Microswitches are located at both the on position and the off position for controlling operation of the motor. The microswitches are actuated by the slide plate assembly which, in turn, is driven by the carriage assembly. The slide plate assembly is slidably mounted with respect to the carriage assembly with one or more wave washers. The slide plate assembly provides mechanical damping for the carriage assembly to minimize damage to the microswitches.

Abstract: Briefly, the present invention relates to a molded case circuit breaker. The molded case circuit breaker includes at least one pair of separable main contacts, mounted on upper and lower contact arms. One end of the lower contact arm is formed as a U-shaped portion defining depending leg portions and a bight portion forming a reverse current loop. Disposed adjacent the lower main contact on the lower contact arm is an arc runner assembly which directs the arc resulting from a separation from the upper and lower main contacts into an arc chute to quench the arc. The arc runner assembly includes an arc runner and a support block. The arc runner may be formed from steel and is carried by the support block, disposed between depending leg portions of the lower contact arm. The support block is formed from an electrically insulating material, such as a glass polyester.

Abstract: A molded case circuit breaker is provided with a magnetic trip device which allow for a relatively wide range of adjustment. The magnetic trip device allows the magnetic air gap to be varied as well as the spring force on the plunger. Additionally, the magnetic trip device allows the force required to rotate the trip bar to be varied. By providing a means for adjust the force required to rotate the trip bar, the adjustment range of the magnetic trip device can be substantially enhanced. The molded case circuit breaker includes at least one pair of separable main contacts. The separable main contacts are mounted on upper and lower contact arms. The lower contact arm may be rigidly mounted to a line side conductor, while the upper contact arm is pivotally mounted to a load side conductor. The upper contact arm is mechanically coupled to an operating mechanism. A pivotally mounted trip bar is operatively coupled to the operating mechanism.

Abstract: A trip interlock assembly trips a circuit breaker any time the circuit breaker is removed from its panel mounting. The trip assembly is adapted to be disposed about a load side terminal and cooperate with the circuit breaker tripping device. In one embodiment, the trip assembly includes a housing and a spring-loaded actuation arm, disposed generally perpendicular to the circuit panel surface. The actuation arm is formed with a cam surface which cooperates with a trip pin adapted to actuate said circuit breaker tripping device. The trip pin acts as a cam follower and rides along the cam surface formed in the actuation arm. When the actuation arm is in an inward position the trip pin is in a normal position. However, when the circuit breaker is removed from the panel, the actuation arm under the influence of a biasing spring moves outwardly. This causes the cam surface on the actuation arm to actuate the trip pin to trip the circuit breaker.

Abstract: A circuit breaker having a trip mechanism comprising a primary armature which is attracted toward a bimetal by magnetic flux produced by a predetermined overcurrent flowing through the bimetal to unlatch an operating mechanism and open electrical contacts, includes a pivoted supplemental armature which is also attracted toward the bimetal by the overcurrent and which bears against and urges the primary armature toward the bimetal to thereby reduce the predetermined overcurrent at which the breaker opens the electrical contacts. The supplemental armature comprises a flat strip of magnetically permeable material which is bent at one end to form a hook which merely drops into a recess in the breaker housing. Integral flanges on the strip form a magnetic yoke which concentrates the magnetic flux to increase the sensitivity of the magnetic trip function.

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 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, a flux concentrating plate spaced from and on the side of the armature opposite the core and for concentrating the magnetic field between the core and the armature, and a hold-back bracket having 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 push-to-trip button for a circuit breaker characterized by a circuit breaker within an insulating housing and having trip means for releasably holding a circuit breaker operating mechanism in an untripped position and including a trip bar biased in an untripped position, a trip delay member biased away from the trip bar and including an adjustment bar for applying a pressure on the member, a trip button extending through the housing and having a first surface contacting the trip bar, and the adjustment bar having a second surface for applying limited pressure on the trip button for holding the first surface in contact on the trip bar, without moving the trip bar to a tripped position.

Abstract: A circuit breaker having a trip delay mechanism characterized by a variable magnetic air gap that is adjustable to permit time delay at low level overcurrents to avoid nuisance tripping during motor starting.