Abstract: A rocking contactor switch of the two-circuit progressive action type having three spaced stationary contacts, a flexible contactor connected to the first stationary contact and self-biased to disengage the second stationary contact, and a three-position rocking contactor. The switch is operable from an "off" position wherein the rocking contactor engages only the first stationary contact and the flexible contactor to a one circuit "on" position wherein the rocking contactor rocks over to press the flexible contactor into engagement with the second stationary contact while remaining in engagement with the first stationary contact, and then to a two circuit "on" position wherein the rocking contactor rocks further to engage the third stationary contacts while maintaining the flexible contactor pressed against the second stationary contact thereby to connect electrically all three stationary contacts.

Abstract: A rocker switch having a spring-biased lock lever within the contact actuator that extends out to catch beneath the rim of the hole in the frame to lock the rocker button in the "off" position. An insertable key, which may include the entire face of the rocker button, has a projecting cam effective when inserted to retract the lock lever to allow normal operation. Removal of the key prevents unlocking of the rocker switch for operation to "on" position. The lock lever has an angular end that allows actuation of the rocker button from "on" to "off" position even when the key is removed. This angular end cams on the frame to momentarily depress the lock lever and allow it to snap below the rim of the hole in the frame. This lock lever is then inaccessible except to the projecting cam of the key.

Abstract: A unitary three-phase current transformer having its three iron cores and three secondary coils enclosed and retained in their positions by a pair of like molded housing halves. The housing halves also have pairs of juxtaposed slots in their upper, adjacent edges for clamping pairs of secondary coil terminal inserts therebetween to mount the same so as to allow connection of the secondary coils to external conductors. The housing halves are connected together by symmetrically arranged sets of screws with the screws of each set extending through holes in the respective half and threaded into the respectively opposite half. The asembled housing halves provide three apertures through which are inserted respective bus bars serving as one-turn primary windings. A terminal strap is attached to one end of each bus bar, the bus bar is inserted through the aperture, and the other terminal strap is attached to the other end thereof.

Abstract: A branch electrical connection is made at any selected joint of a busway run without disturbing the joint connection in any manner apart from removing a side housing cover plate. A unitary connector assembly is plugged into the exposed side of the joint and bolted to the bus duct housing using the existing bolt holes provided for the joint cover.

Abstract: A multipurpose electric trigger switch adapted to be mounted in the handle of a portable electric tool for controlling the A.C. power circuit and, to afford a higher rating, the switch is provided with double-pole butt contacts. The contacts of the switch have a controllable amount of wipe, very low bounce, are non-teasible, have steady contact pressure at the point of tripping open, and have a considerable amount of trigger lever movement between trip "on" and trip "off" positions. The amount of wipe is controlled by the amount of flexure of flexible contract terminals. The low bounce and non-teasibility are controlled by the angular rocking of a spring-biased self-centering rockable plunger and the snapping action of an actuator having camming surfaces in engagement with the plunger and rocking surface in engagement with the flexible contact terminals. Steady contact pressure at the point of tripping open is achieved due to an inclined camming surface of the actuator rising to an apex point.

Abstract: Electric receptacle apparatus having a ground fault detector and current interrupter. The apparatus may be mounted in the standard receptacle box used for housing a double socket outlet. The apparatus includes means for automatically testing the operation of the system upon connector plug insertion and means for providing a visual indication of the occurrence of a ground fault.

Abstract: A double-throw rocker switch having a selectively shiftable lockout member which when shifted to one lateral position allows depression of only one end of the rocker button and when shifted to the opposite lateral position allows depression of only the other end of the rocker button. This lockout member is secured to the center of a mounting shaft having pushbuttons at its ends and this shaft is mounted to the switch housing for limited lateral sliding movement sufficient to shift the lockout member, this shaft serving also as a pivot pin for the rocker button and the contact actuator. This selective lockout may be used in a tool reversing application where plugging of the motor could be hazardous.

Abstract: A vacuum contactor for motor control applications and method of making the same that produces a switch of minimum size and extremely long mechanical life. This method comprises the step of heating the vacuum assembly to not over 450.degree. C during the evacuation process thereby allowing use of welded diaphragm bellows having the attendant advantages of much smaller size and longer life for a given length of stroke as compared to formed bellows. Because the operating conditions for motor control applications do not require as high voltage and current breakdown levels and thus the residual gas level inside the vacuum contactor enclosure need not be as low as in the case of circuit breaker (interrupter) applications, limiting the heating to not over 450.degree. C allows use of AM-350 stainless steel welded diaphragm bellows without sacrificing its required mechanical life.

Abstract: A rocker switch having non-illuminated indicator means comprising a ribbon or sheet member which effectively slides along the interior surface of a rocker cap having a window visually exposing the appropriate indicia on the ribbon as the rocker is pivoted. The ribbon is flexible enough to assume the interior shape of the rocker cap and stiff enough to slide therealong during rocking operation. A window or lens may assume various positions on the rocker cap with appropriate positioning of indicia on the ribbon therebeneath.

Abstract: A toggle lever for operating an electric switch and easily assembled, anti-rotation means for mounting the lever for limited pivotal movement within the mounting bushing of the switch. The toggle lever has an intermediate enlarged spherical portion including two short trunnions extending in opposite directions therefrom. The mounting means comprises a pair of interlocking semi-cylindrical molded insert halves having on their inner surfaces an annular socket for the spherical portion and each having a central hole to journal the corresponding trunnion when the two halves are placed therearound to form a subassembly.

Abstract: An improved limit switch operator head assembly is disclosed. The assembly includes a rotatable operating shaft which is rotatable in reverse switch commutating directions, and a helically coiled torsion spring for effecting return of the operating shaft to a center or non switch commutating position. It further includes a U-shaped member formed of thin spring steel which is held in friction producing abutting relation against the coils of the torsion spring to damp the snap-back action of the latter and thereby prevent reverse rotations of the operating shaft beyond its center position.