Abstract: A switchgear installation has at least four junctions connected in the form of an annulus. These junctions are connected with each other by means of interruptable current branches. Each junction of a first group of junctions containing at least two elements may be connected with each junction of a second group of junctions by means of a bridging branch. The bridging branches contain a common power or load switch together with a plurality of disconnecting switches, which are provided between a first supply terminal of the power or load switch and each junction of the first group and between a second supply terminal of the power or load switch and each junction of the second group.

Abstract: An improved electronic circuit module retainer apparatus having interlocking, wedge-shaped components which are slotted and keyed together to allow tightening using a single screw which can be turned from the module insertion side of a module enclosure. A module retainer has a minimum of three interlocking parts which are held together by a tightening screw. A center body of the module retainer has holes for attaching it to a module or a module enclosure; it has a U-shaped channel with a square cross section and sloped ends. Each end body has a keying guide extending from a sloped end. A screw extends through a clearance hole in an end-body, then through the center body U-shaped channel and finally into a threaded hole in an opposite end body. When the screw is tightened, the end bodies slide along the sloped ends of the center body causing them to wedge the module against the module enclosure walls.

Abstract: A printed circuit heatsink technique and assembly is disclosed which increases the heat dissipating capabilities of a printed circuit assembly. A thermally conductive plate is etched using the same artwork or mask employed to define the patterns of terminals and conductive areas on one surface of a printed circuit board. The plate is etched in those regions corresponding to the terminal and conductive areas so that holes are produced in the terminal areas and channels are produced in the conductive areas. The plate is then bonded to the printed circuit board prior to the attachment of the leads of electronic components through the holes formed in the thermally conductive plate. The assembly absorbs heat generated by the electronic components and provides a greater surface area for dissipating that heat without the need for specially fabricated heatsink elements or complex milling procedures.

Abstract: A technique and assembly is disclosed which allows more effective heat dissipation in a printed circuit assembly. A heatsink plate is etched using the artwork or masks used to form the conductive strips and terminals on a conventional printed circuit board. The heatsink plate is secured over at least a portion of the surface of the printed circuit board by an adhesive and the resulting heatsink assembly is mounted adjacent to a thermally conductive bracket. The heatsink assembly is then secured to the bracket by a wedge clamp which includes mating wedges configured to provide a high thermally conductive path between the heatsink plate and bracket for dissipating heat generated in or about the printed circuit heatsink assembly. The clamp configuration is such as to allow slidable movement between similarly shaped wedges which produces proper formation of the thermally conductive path during clamping.The Government has rights to this invention pursuant to contract No.

Abstract: Means for fixing a device on supporting a channel bar comprise a leg (5), a fixing component (2) and a compression spring (3). The fixing component has a rod (12) and a body (11) which slide in a longitudinal guide (24) in the base (1) of a housing for said device to be fixed on the bar. Two recesses (9, 10) are provided in the base. The compression spring is installed in a partially compressed condition in the first recess (9) and the rod (12) passes through it, said rod forming shoulders (19) with the body. The end of the rod (12) is fitted with a pin (4). The fixing component has two hooks (13, 14) and a guide (15) which co-operates with a groove (27) of the base to make the fixing component captive.

Abstract: A circuit breaker and mating adapter plate combine to fit a panel opening intended to receive larger breakers. The adapter plate has one resilient and one rigid leg, each with inturned lips so that the adapter can be clipped onto the face of the breaker. One mounting screw utilizes a conventional threaded opening in the breaker, the other attaches to the adapter only.

Abstract: An improved drawout carriage assembly for the contactor of a high voltage controller. The controller carriage is fabricated from a pair of sheet metal sides, interconnected at their lower edge by formed sheet metal cross members. The upper portions of the sides are comprised of planar sheets of insulating material. A series of insulative cross members are bolted between the opposed faces of the carriage side pieces and locate elements of the contactor mechanism.

Abstract: A shield mechanism for isolating line and load stabs within a 2500-4000 ampere circuit breaker compartment is disclosed having a primary operating arm for operating a lower moveable shield and an upper moveable shield interconnected by a reversing bell crank link. Interconnection between the bell crank link and an intermediate lever is made by means of a lower expansion link. The corresponding downward motion fo the lower expansion link, when the circuit breaker is inserted in the compartment, forces the upper moveable shield to pivot into an open clockwise direction by connection between the upper moveable shield, the bell crank link and an upper expansion link against the force exerted by a return spring. Direct connection between the lower moveable shield and the intermediate lever forces the lower moveable shield into an open counterclockwise direction.

Abstract: A Z-shaped bracket (42) is secured to a circuit breaker panel (2) by a fastener (44) to project forwardly along a plug-in main circuit breaker (30) and overlie the forward surface of the main breaker to prevent removal of the main breaker (30) without first removing the bracket (42). The bracket and its function are made plainly evident by placement and indicia.

Abstract: An electric circuit breaker panelboard equipped for lug main connection (22,24) and having a plug-in main circuit breaker (26,28) held securely in place by bracket (36) secured to the panel (2) by a screw (38) and having a forward hook (36c) overlying a forward edge (26c) of an insulating barrier adjacent the load side connector (26b) of the breaker. The bracket (36) has a ledge (36d) overlying a mounting rail (2b) on the panel (2) in position below the hook portion (36c) such that movement of the breaker (26,28) in a direction to cause separation of the plug-in electrical connection thereof with the panelboard exerts a bending on the bracket and a compressive force on the mounting rail to resist such movement. The bracket is colored red to be clearly visible and serve as a warning against removal of the main breaker under electrical power.

Abstract: An electrical jack is supported, at its front end, on a circuit board, by a thin flat member having an aperture therein which is a sliding fit over a tubular extension on the front end of the jack. The flat member has a tongue extending radially inward of the aperture, the tongue being bent or deformed on insertion of the tubular extension in the aperture. The tongue grips the extension and sustains the flat member in position prior to attachment to the board. Legs on the bottom edge of the flat member pass through the circuit board and are attached to the back surface of the board, as by soldering. Terminals at the rear end of the jack pass through the board and are connected to a circuit. The flat member can have a plurality of apertures, for the support of a plurality of jacks positioned together.