Abstract: A mechanism assembly is for a vacuum circuit interrupter including a vacuum housing including a stationary contact and a moveable contact, and an operating mechanism including a drive rod. The mechanism assembly cooperates with the drive rod to open and close the contacts. The mechanism assembly includes a housing having a pair of first longitudinal openings and a pair of second longitudinal openings, the first longitudinal openings defining a first plane, the second longitudinal openings defining a different second plane. A first trunnion member is pivotally and translationally mounted with respect to the first longitudinal openings. The first trunnion member is coupled to the moveable contact. A second trunnion member is pivotally and translationally mounted with respect to the second longitudinal openings. The drive rod is pivotally connected to the second trunnion member. A pair of compression springs are biased between the first and second trunnion members.

Abstract: The present invention provides improved and more efficient methods and apparatus for maintaining and/or adjusting over-travel gaps and contact wipe portions in operating rod assemblies of circuit interrupters.

Abstract: A slide bar interlock for interlocking adjacent first and second circuit breakers having dissimilar actuating means and preventing the first and second circuit breakers from simultaneously being in a closed operating position. The slide bar interlock includes a housing and a slide bar received in the housing. The slide bar includes a first end which extends from the housing adjacent to the first circuit breaker and a second end which extends from the housing adjacent to the second circuit breaker. The slide bar is slidable between a first position where the first end of the slide bar blocks operation of a pivoting actuating handle of the first circuit breaker and a second position where the second end of the slide bar maintains a push-to-open button of the push button actuating means of the second circuit breaker in an actuated position.

Abstract: A bell alarm system is provided for a circuit breaker in which the actuation of a flux shift trip device causes an electrical switch to be energized thus providing a bell alarm indication that the circuit breaker has been tripped. The flux trip device impinges against a pivotally rotated lower lever mechanism which has a knee which causes rotation of an upper lever against the influence of a spring attached between the two levers. As the knee moves along a surface of the upper lever mechanism, the relative rotation of the two lever members about their support pins is such as to cause the tension on the spring to increase. Because of this vibration in the circuit breaker itself or minute low level movements of the plunger mechanism will not cause the bell alarm to be actuated.

Abstract: An apparatus selectively connects a normal power line and an emergency power line to a load, and includes two interlocked switching mechanisms, each having individual interlocks, for selectively connecting the power lines to the load, and an interlock mechanism for interlocking the switching mechanisms in order that only one of the power lines at a time is connected to the load. The switching mechanisms may each have two drawout cassettes including associated switching devices for switching the power lines to the load and, also, including an isolated position for isolation of the associated switching device from at least one of the switched power lines and the load. Each switching device may be a circuit breaker having a trip unit for sensing current flowing from a power line to the load and tripping the circuit breaker. The interlock mechanisms may include keylock mechanisms which selectively disable closing of the switching devices.

Abstract: A powered mechanism displaces the toggle, handle or similar operator of a switch such as a circuit breaker, motor contactor or transfer switch. A linear induction motor drives a motor shaft between extended and retracted positions. A pair of S-shaped cam members pivot at one end on an axis, and a sliding pin carried on the end of the motor shaft rides along slots in the cam members. A couple engages over the switch operator and is pivotally attached to links that in turn are pivotally attached to the cam members, The links attach to the cam members at a point closer to the pivot axis of the cam member than the sliding pin in the slots, thus obtaining leverage. The slots have an inclined or curved section joined to a straight section. The straight section provides an idling action in that no force is applied to the operator via the couple as the sliding pin passes through the straight section, allowing the motor to accelerate unopposed.

Abstract: An interlock for a pair of electrical switching devices includes plungers mounted through the switch housing and engaging the operating mechanism which opens and closes the switch. The plunger of each switch is coupled to a pivotally mounted cam plate by a pin which engages a camming slot in the cam plate for mutual movement of the plunger and cam plate. The cam plates associated with the pair of switches are connected by a connecting link for coordinated rotation. When one switch is closed, the operating mechanism extends the associated plunger which through the cam plates and connecting link raises the other plunger to block closing of the other switch. When a plunger is in blocking position, the coupling pin engages an overtoggle section of the camming slot of the associated cam plate such that a force generated by any attempt to close the associated switch is directed through the pivot axis of the cam plate and generates no component tending to rotate the cam plate.

Abstract: A handle actuator is provided for a circuit interrupter that has a handle or toggle pivotally movable between operative positions. The handle actuator has a pair of pins that fit tightly on the handle, a pair of retainers coupling the pins in a rigidly spaced parallel relationship, and a pair of flanges fixed to the circuit interrupter via a base. The flanges are disposed on opposite sides of the handle and have arcuate slots that guide the pins coaxially with the pivot axis of the handle. The ends of the pins extend through the arcuate openings of the flanges and are received in the retainers. Connecting links pivotally couple the pins with a drive input for selectively driving the pins against the handle to move the handle between the operative positions. The relative position of the pins on both sides of the handle is constant, preventing wear on the handle due to rolling of the pins against the handle, impacts with the handle permitted by lost motion, or bending and twisting forces.

Abstract: A transfer switch mechanism is provided for operating the handles of a pair of circuit interrupters. The transfer switch mechanism has a lever arm movable between advanced and retracted positions, the lever arm having a gripping portion permitting handhold for manual operation. The lever arm turns an axle via a ratchet assembly with pawls that permit the axle to turn in one direction but oppose movement of the axle in the direction counter to that direction. The axle turns a crank, and a pair of connecting rods have proximal ends coupled to the crank. The transfer switch mechanism further includes a pair of handle-engaging heads, each of which has opposed abutment surfaces that removably receive the handle of one or the other circuit interrupters between the opposed abutment surfaces. A base is fixed relative to the circuit interrupters and movably supports the lever arm and the handle-engaging heads.

Abstract: A mechanism for bypass isolation switches of the type comprised of at least three circuit interruption devices each having a handle has at least three switch gears, one positioned over each circuit interruption device and having either a drive gear or a spacer gear therebetween. A cam having a mouth which engages the handle of the circuit interruption device is eccentrically mounted on each switch gear. A stop is provided on at least one gear to permit the gears to rotate only 180.degree.. Since the drive, spacer and switch gears are interconnected, the cams must move or not move simultaneously. As a result, the at least three circuit interruption devices are operated simultaneously.

Abstract: An alarm assembly for use with a circuit breaker is provided. The assembly is used with the flux shunt trip device of the circuit breaker. The flux shunt trip device has a plunger which moves from a retracted position to an extended position to interrupt current through the circuit breaker upon a predetermined condition. The assembly includes an actuating member mounted in engageable relationship with the plunger so that when the plunger moves to its extended position, the actuating member moves to an actuated position. In the actuated position, the actuating member contacts a switch mechanism to actuate a switch which may be connected to an alarm or light indicator to identify that the circuit breaker has tripped. The actuating member remains in its actuated position until it is manually reset. A mechanism is provided for reset of the device.

Abstract: An uninterruptible power source having a static transfer switch which switches rapidly between a commercial power source and an alternate power source is removed from service by a maintenance bypass switch having a first switch in series with the uninterruptible power source and a second switch which shunts the uninterruptible power source and the first switch. The first and second switches are circuit breakers having handles which toggle between open and closed positions. The maintenance bypass switch includes an operator which operates the two circuit breakers in opposition with a closed transition so that one switch is always closed. An interlock prevents operation of the maintenance bypass switch when the alternate power source of the uninterruptible power supply is selected by the static transfer switch.