Abstract: A current transformer characterized by a terminal bushing extending from a tank with a pair of spaced conductors extending through the bushing and into the tank and with the portions of the conductors in the tank being enclosed within tubular means. The assembly of the conductors, bushing, and tubular means being clamped together by resilient (spring) means for holding the conductors in tension and the bushing and tubular means in compression. The transformer also embodies two separate oil systems.

Abstract: A circuit breaker with an arc shield characterized by a movable contact assembly which is rotatable between open and closed positions with respect to stationary contacts, and a cylindrical arc shield mounted on the assembly and rotatable therewith.

Abstract: A three-phase transformer including tap changing apparatus for switching the turns ratio between the primary and secondary windings of a transformer. The tap changer comprises a cable operated mechanism for moving a movable contact carrier relative to three sets of fixed contacts disposed in a linear pattern, the movable contact carrier supporting three movable contacts for engagement with any pair of fixed contacts in each set of contacts, whereby a cable operated mechanism provides a high degree of flexibility in switch mounting position on a transformer.

Abstract: Vapor cooled induction apparatus having a winding with predetermined surface irregularities on the turn surfaces of the winding to provide spaces to permit a cooling/insulating vaporizable liquid dielectric to flow between the turn surfaces of the winding to enable a film of the insulating cooling detection to be deposited on the surface area of the winding. The surface irregularities may be transverse grooves disposed at predetermined intervals in at least one surface of an elongated metallic conductor used to form the winding or they may be bosses of insulation disposed on a predetermined spacing on at least one surface of the elongated metallic conductor. Also disclosed are a method and apparatus for forming precisely spaced grooves in the surface of a continuously moving elongated conductor and thereafter insulating the grooved conductor with a uniform, solid, homogeneous coating of electrical insulation.

Abstract: A reinforced structure for resisting deflection of a tank wall that is subjected to a range of positive and negative pressures within the tank characterized by a plurality of closely spaced braced members disposed in general alignment and mounted on the tank wall so that upon limited deflection of the wall the brace members move into contact and thereby increase wall resistance to additional damaging deflection.

Abstract: A secondary circuit breaker for a distribution transformer characterized by electrical inductive apparatus within an oil-filled housing, and circuit interrupter for controlling current flow through the transformer and comprising a releasable latch arm, trip means operable upon overload conditions to release the latch arm, a latch lever between the trip means and the latch arm and comprising the only operable part therebetween, and the latch lever having a cam surface for latching and unlatching the releasable arm.

Abstract: Electrical inductive apparatus characterized by pancake coils comprised of an outer layer and a plurality of inner layers formed by spirally winding an elongated conductor which conductor has a plurality of strands formed in a row of strands in each layer including an end strand at each end of the row, the end strand being enclosed in dielectric covers with each layer being encased in a dielectric casing, whereby the end strands of adjacent layers are sufficiently insulated to prevent electrical breakdown therebetween.

Abstract: A watthour meter enclosure with tamper resistance means characterized by a meter cover and a meter base assembled for preventing unlocking rotation of the cover and including locking means between the base and cover for preventing unlocking and/or for indicating surreptitious tampering if it occurs.

Abstract: A power transformer characterized by inner and outer low voltage winding sections and a high voltage winding section disposed therebetween. The low voltage windings are comprised of a plurality of pancake coils, and the high voltage winding are comprised of a plurality of conductor strands spirally wound for a plurality of coil layers. The low and high voltage winding sections are laterally spaced with the low voltage windings disposed in side-by-side positions and adjacent to the high voltage windings. The high voltage windings having a smaller turn height than the low voltage windings and having conductor strands of smaller gauge than the pancake coils of the low voltage windings.

Abstract: A coil winding procedure for winding pairs of coils, whereby a first coil is wound inwardly to the start and the second coil is wound from the start to the finish lead from the same continuous conductor strand, thereby eliminating the need for a start-start brazing operation.

Abstract: A laminated magnetic core characterized by an electromagnetic core having core legs which comprise elongated apertures and edge notches disposed transversely to the longitudinal axis of the legs, such as high reluctance cores with linear magnetization characteristics for high voltage shunt reactors. In one embodiment the apertures include compact bodies of microlaminations for more flexibility and control in adjusting permeability and/or core reluctance.

Abstract: A circuit breaker mechanism for use with a transformer characterized by a pair of open-close load break switches operated by a single handle through two four-bar linkages for operating the switches simultaneously between three- or four-position combinations.

Abstract: A retort pipe seal characterized by a retort and a crucible and passage means therebetween; a closure diaphragm for closing said means; means for heating the crucible; and rupture means for rupturing the closure diaphragm to enable a reactant in the retort to transfer to the crucible at a predetermined temperature.

Abstract: Electrical inductive apparatus having a tank, an insulating and cooling liquid in the tank and an electrical winding structure immersed in the liquid, the liquid having a low vapor pressure and containing contaminants derived from various sources within the tank. Filter means associated with the liquid including a liquid recirculating device for degassing, demoisturizing, and filtering insoluble particles out of the liquid, whereby the liquid is decontaminated and upgraded in a continual process.

Abstract: A transformer motor pump unit for circulating a fluid in a transformer characterized by a rotating pump shaft mounted in non-electrically conductive bearings, means for detecting shaft displacement due to bearing wear, and a static arrester grounding the pump shaft and all rotating parts for preventing static electricity buildup on the shaft and subsequent discharge from the shaft to the bearing area. Power circuit means for operating the pump includes the static arrester as a control circuit for tripping the pump out of operation should mechanical failure occur.

Abstract: A resistance thermal unit for a thermal electric energy demand meter responsive to a variable electric quantity characterized by a dielectric housing having a pair of opposed chambers for accommodating a pair of thermal responsive bimetallic spiral springs wound on a common shaft, the springs being effective when heated to rotate the shaft in opposite directions, heating means including a heating element for each spring which element includes a flattened heat resistant dielectric core and an electric-resistant wire spirally wound on the core which wire is connected to spaced load terminals, and the assembly being disposed in a clearance space around each corresponding spring.

Abstract: An oil-immersed switch characterized by movable contacts mounted on a piston for movement in a cylinder for forcing oil or dielectric fluid through stationary contacts for extinguishing any arc during opening and closing of the contacts, and whereby any arcing generated during closure of the contacts generates gas pressure which acts upon a piston for aiding enclosure of the contacts.

Abstract: Apparatus for firing ceramic greenware including a container and a plurality of independently movable granules disposed within the container so as to provide a readily levelable minimum friction support surface for supporting the ceramic greenware. During firing, those granules which contact the greenware move in correspondence with the shrinkage of the greenware so that friction related distortion of the greenware is reduced. The ceramic greenware is fired by a method which includes providing a sufficient depth of granules to permit relative movement of those granules in contact with the ceramic greenware, leveling the surface of the granules, placing the greenware on the level surface and firing the ceramic greenware.

Abstract: A transformer cooling structure characterized by a plurality of coolant fluid cooling panels extending outwardly from the transformer tank wall, and the panels being comprised of a pair of sheet-like sides formed to a corrugated configuration through which the fluid flows in heat exchange with ambient air.

Abstract: A circuit breaker with unitary actuating shaft characterized by a dielectric housing having separable housing sections for mounting opposed stationary contacts; a unitary, hollow actuating shaft for mounting movable contacts between open and closed positions with the opposed stationary contacts; and each section having an end wall with an aperture through which the shaft extends and is retained in alignment.