Abstract: A holder for retaining mirror symmetric E core halves of an electromagnetic core structure consists of angle pieces each having a leg disposed parallel to abutting sides of the E core halves and each having another leg extending around a straight outer surface of one of the halves. The parallel legs engage a retaining plate and terminate in threaded ends for receiving bolts to force the E core halves together and retain the halves by pressure exerted on the outer surfaces of the halves. The threaded ends of the angle pieces extend a sufficient distance for utilization of the holder to mount the electromagnetic core on a circuit board.

Abstract: A pulse transformer having primary and secondary windings on separate insulating bobbins which are carried on the arms of a pair of U-shaped ferrite cores which provide a continuous magnetic path for coupling relatively high energy pulses. The bobbin and core assembly is assembled in and held together by a close fitting molded plastic housing which carries four pins to which the primary and secondary windings are attached. The connecting pins extend from a side of the housing which is open to receive the bobbin/core assembly and are adapted for printed circuit board mounting in which the board covers the housing opening so that the transformer is completely protected.

Abstract: A holder for an electromagneticcoil assembly comprised of joined mirror symmetric E core halves has two bracket pieces which are disposed adjacent to joined legs of the E core halves, each bracket having a pair of bores therein for receiving at least one retainer rod. The rod extends through the brackets and an alignment bore or groove in the core halves. In one embodiment of the holder a retainer plate having bores in registry with the bracket bores also receives the retainer rod, with nuts applied to threaded ends of the retainer rod to exert a uniform retaining pressure along opposite faces of the core halves to maintain a substantially constant core air gap and maximize vibration resistance.

Abstract: A transformer having a core and coil assembly which includes a pair of cores disposed side by side, the core members being of the squared "O" type formed of a plurality of nested, generally rectangular laminations. A space is provided between a pair of adjacent laminations in corresponding locations in each core, and a coil surrounds the adjacent sides of the respective cores through the central openings of the cores. Also included is a terminal board support having a pair of tabs to be inserted in the spaces between the adjacent laminations, the tabs being provided with holes having extruded edges for frictional engagement with the core laminations. The core and coil assembly is placed upon a flat base member and a U-shaped band is placed so as generally to encompass the top and two sides of the core and coil structure to make contact with a part of up-turned flanges of the base member.

Abstract: To permit adjustment of the air gap of an inductance unit suitable as a ballast for fluorescent lamps particularly in form of a leakage transformer or as a choke, for multi-voltage connection, an outer, essentially U-shaped core structure (1, 100), and having an integral connecting cross element (1, 101a), and two parallel leg elements (1b, 101b), has at least one longitudinally slidable cross element (2, 2', 2"; 3, 3'), the cross element being formed with a central longitudinal core element (14, 15; 14', 14") extending parallel to the leg elements, and short of the adjacent cross element, and longitudinally slidable within the leg elements so that the air gap between the longitudinal element and the adjacent cross element, and forming a magnetic shunt, can be adjusted after manufacture of the attached laminate to compensate for manufacturing tolerances and provide an inductance element having design impedance regardless of variation in the size of the longitudinal core element.

Abstract: Improved end clamping members are used in transformers having a horizontal magnetic circuit which is preferably of rectangular cross-section.Each end clamping member is embodied by juxtaposed longitudinal beams--side beams (4) comprising magnetic laminations on edge over substantially their whole thickness, and intermediate beams (5) comprising magnetic laminations on edge over only some of their thickness, the end clamping member being embodied for the rest by a longitudinal flat iron member (15), and each group or set of magnetic laminations has at its center the longitudinally extending wedge-shaped member and on each side another longitudinally extending flat iron member of the same width.The invention is of use more particularly for high-power shell type transformers in a form-fit tank.

Abstract: Each of the plurality of metal strips combined to form a core unit has a width b substantially less than the radius r of the cross section of the core formed by the strips. The direction of the edges of the strips in the cross section is random.

Abstract: An adjustable transformer core and the method of manufacturing an adjustable transformer core, the transformer including a core and coils, the core being formed from a plurality of lamination sets, each lamination set including a number of legs and a pair of yoke members, the lamination sets being stacked in face-to-face relation so that the legs can be moved relative to each other. The coils may be wound directly on the legs and are moved toward each other to obtain predetermined characteristics. The coils are enclosed within a pair of core clamps to retain the relative position of the coils. Such adjustment can be employed to obtain different impedance or insulation levels. It is also within the contemplation of this invention to use the core as a common core for a variety of transformer designs.

Abstract: An inductor such as a fluorescent lamp choke comprises a bobbin carrying a winding, a laminated core, and a sheet metal casing consisting of two parts which have interengaging flanges and grooves along four parallel edges which are slid together and subsequently bent over and pressed against end faces of the core to secure the parts of the casing together so that they exert pressure on the core from all sides.

Abstract: Electrical inductive apparatus having improved support structure for a magnetic core and winding assembly. The support structure includes end plate assemblies, each having a substantially tubular cross-sectional configuration, which are disposed in abutting relation with the outermost turns of the winding assembly and joined to top and bottom end frames disposed adjacent to the top and bottom yokes of the magnetic core. In another embodiment, upper core braces are situated above the winding and are adjustably disposed between the outermost legs of the magnetic core and the end plate assemblies. Lower core braces are disposed below the winding and include members which are disposed in abutting relation with the core legs and joined to bottom end frame.

Abstract: A high frequency drive circuit operating as a push-pull, Class C oscillator for driving a high-intensity, gaseous discharge lamp and avoiding the use of a relatively large ballast coil. A highly stable power supply for operating in conjunction with such circuit is also provided.

Abstract: An arc welder has a transformer comprising a pair of flat aligned primary coils of aluminum strip wound on opposite parallel legs of a rectangular open frame core and a pair of aligned secondary coils of the same strip material wound on the same opposite parallel core legs in lateral spaced relationship with the primary coils, a flexible strip encircles each pair of aligned coils tightly banding them against lateral distortion, a flux shunting core encapsulated in molded plastic material is slidably movable through the core between the pairs of aligned coils, and mechanism for slidably moving and locking the shunting core in adjusted positions is operated by a single handle. One secondary coil of the pair comprises two windings, one wound over the other to provide two output ranges. In a modification, the addition of an outboard choke coil of round wire provides a third output range.

Abstract: A transformer assembly comprising a core structure having an open space, primary and secondary coil units mounted either in parallel or in concentric relationship on the core structure, and a unitary insulating envelope of heat-resistant dielectric material such as silicon rubber, the insulating envelope a portion encapsulating the windings of the primary and secondary coil units and a portion occupying that area of the above mentioned open space which is subject to production of a corona discharge due to the high voltage to be developed in the secondary coil unit. The insulating envelope is formed by injecting the dielectric material of fluid state into a mould to which the subassembly of the core structure and coil units is fitted in part of in its entirety except for terminal elements. A partial vacuum is established in the mould so that the insulating envelope produced is void-free.

Abstract: In a laminated magnetic core wherein an adhesive is utilized to secure laminations in a unitary structure, low core compressibility is obtained by restricting the distribution of adhesive so that regions of metal-to-metal contact which surround axial compression points are kept completely free of adhesive. The core is formed by placing the laminations in assembled relation and applying a limited amount of the adhesive in a liquid state to selected core surface areas. Isolated interlaminar regions which lie intermediate of the axial compression regions are filled by the adhesive which flows therein by capillary action. The quantity of adhesive applied is carefully controlled so that capillary migration is contained wholly within the isolated bonding regions.

Abstract: A bobbin construction, particularly for windings surrounding an assembly of ferromagnetic laminations, is described. It consists of a skeletal frame member of molded plastic having an elongated shape, generally of rectangular cross section, over which a winding may be wound. The frame member has laterally extending walls which define the space for the windings and axially extending walls defining the space of the laminations. The latter walls are so constructed as to support covers for enclosure of the core assembly.

Abstract: A rotary transformer includes rotor and stator cores arranged apart from each other. The rotor core is made of a plurality of U-shaped core plates which are laminated around a rotary shaft and supported by a pair of plates engaged with the opposite side ends of the rotor core and by an insulative band winding the bottom of the annular recess for receiving a rotor coil.

Abstract: A reactor core includes a plurality of laminations of trapezoidal shape forming the legs of the core. These legs are arranged in generally rectangular configuration with air gaps provided at the corners of the core. These air gaps extend diagonally of the core legs and are formed between the inclined faces of adjacent ends of the trapezoidal-shaped core legs. End plates each having a longitudinal section extending parallel to and fixed to one of the legs and having flanges at each end of the longitudinal section extending perpendicularly to the longitudinal section are provided for maintaining the legs of the core in assembled relation and for effecting adjustment of the air gaps. The end plates include elongated openings in the flanges thereof for permitting movement of each of the end plates, and the leg to which it is affixed, relative to the remainder of the core for varying the size of the diagonal air gaps.

Abstract: A precut nested magnetic core having a locking outer turn. The locking turn is formed of magnetic core steel and has a pair of locking slots in one end and a single locking tab in the opposite end. The precut annular core is locked by using the second or inner slot with the locking tab while the formed annealed core is locked by using the first or outer slot with the locking tab.

Abstract: A clamping ring and static plate used for axially compressing the ends of a cylindrically shaped power transformer winding. The electrically conductive static plate portion of the combination device is formed around and is insulated from a foundation providing, high-strength material, clamping ring. In addition to saving material and space, the use of two or more of these devices concentrically positioned, permits the application of unequal clamping forces to concentrically positioned windings; at least one of these devices having reduced insulation requirements.

Abstract: For hydraulically clamping transformer windings, hydraulic pressure generating boxes are arranged between the bottom wall of the transformer tank and a plate which supports the transformer yoke. The transformer coils which surround the legs are supported from the plate by clamping boxes which are connected by conduits to the pressure generating boxes to transmit hydraulic pressure therebetween.