Abstract: Inductive microcomponent (1), such as a microinductor or microtransformer, comprising a metal winding (2) having the shape of a solenoid, and a magnetic core (4) including a strip made of a ferromagnetic material, positioned at the center of the solenoid (2), and characterized in that the core comprises at least one additional strip made of a ferromagnetic material (13), separated from the other strip (12) by a spacer layer (14) made of a non-magnetic material, the thickness of which is such that the strips (12, 13) located on either side of the spacer layer (14) are antiferromagnetically coupled.

Abstract: A high-frequency choke coil achieves the same low loss across a wide band as a choke coil comprising an external resistor, without using an external resistor. The choke coil comprises a wire-like conductor, wound around a rod-like core; a plurality of individual rod-like cores are joined parallel to their axes with insulators therebetween, forming a rod-like core having a predetermined length; one of the individual rod-like cores has at least (i) a specific dielectric constant at 1 MHz which is more than five times that of the other individual rod-like cores, and/or (ii) a volume resistivity which is less than one-hundredth of that of the other individual rod-like cores.

Abstract: This invention relates to the planarization of inductive components by reducing standard coiled designs to single turn designs from which the required parameters are obtained by scaling the length. Single turn designs having magnetic material encircling the conductors along their full length enable the thinnest form. The single turn form also enables the inductive component to be routed according to any shape in the plane or on any conformal surface. The single turn inductors do not need to coil hence there is no overlap necessary in the plane. The planar form allows integration of inductive components with integrated circuits. These inductive components can be embedded in other materials. They can also be fabricated directly onto parts.

Abstract: The invention relates to a current transformer for three-phase systems and it used to detect currents, for example with three-phase current meters or electronic devices which trigger low voltage protection breakers. The invention aims at developing a current transformer that can be produced and fixed in a simple and low cost fashion and permitting to measure total current. Therefore, four mutually spaced apart, parallel, identical cylindrical conversion coils (4-7) are provided. In each case, a three-phase current lead (1, 2, 3) runs between two conversion coils (4-5, 5-6, 6-7) arranged adjacent and substantially normal to their longitudinal axes (10). Conversion coils (4-7) are held headwise through two low coercivity yokes (8, 9) extending in their longitudinal axes plane.

Abstract: A choke for suppressing radio interference, having a terminal wire composed of an electrically conductive and thermally conductive, non-ferromagnetic, first alloy and having a magnetic tape core composed of a ferromagnetic, second alloy. The magnetic tape core includes a thin band wound into a coil around the terminal wire that has one end positively connected to the terminal wire. In addition, an optimum thermal contact of the magnetic tape core with a printed circuit board via the terminal wire implemented as current-carrying conductor is achieved by the to choke. As a result, an excess temperature occurring in the magnetic tape core can be reduced to values compatible for the alloys employed. In this way, the problem of aging, which depends functionally on the temperature, can be dramatically minimized.

Abstract: This current transformer is provided, in particular, for a metal-enclosed gas-insulated high-voltage installation. It has a toroidally formed current sensor enclosing a current path and a signal processing system downstream of said sensor. The current sensor is surrounded by an electrically conducting screen which encloses an annular cavity filled with a compound (4). The screen is interrupted by a circumferential gap (9) designed as an interruption in the screen. It is intended to provide, for metal-enclosed gas-insulated high-voltage installations, a current transformer which is insensitive even to extremely high-frequency electrical interferences, which is inexpensive to construct and which is notable for small dimensions and for a high measurement accuracy. This is achieved by designing said interruption in the screen so that it is effective during the normal operation of the current transformer (1) and is shunted if high-frequency interferences occur.

Abstract: An inductive component for the attenuation of common mode and push-pull interferences in n-lead systems with n≧2 leads, includes a body of a permeable material having n bores formed therein. Electric leads are disposed in the bores.

Abstract: A ferrite-core housing case 20 has a first split case half 21, and a second split case half 22 that is openable with respect to the first split case half 22, and houses a ferrite core 1 for a flat cable. A pair of spring portions 27 which press the ferrite core 1 are formed in at least one of the first and second split case halves 21 and 22, and a fulcrum of each of the spring portions 27 is located on a side face 22b of the split case half while an acting point is located on a center side.

Abstract: An electric noise absorber for clamping to a cord of an electronic device comprises a holding case composed of two box-shaped case members. Each case member contains a magnet having a hemi-cylindrical groove at the upper part of the magnet for receiving the cord. It is possible to easily and securely attach and detach the electric noise absorbing magnet to the cord by simply closing and opening the case members.

Abstract: A surface mount self-induction component comprises a drum core having a winding core around which a winding is to be wound, and a pair of flanges which are opposedly placed at ends of the winding core, respectively, a plate core which elongates above the pair of flanges, and electrodes which are respectively formed on side faces of the opposed flanges, the side faces being parallel with an axial direction of the winding core, a diameter of the winding being collapsed by pressurizing or heating, thereby connecting terminals of the winding to said electrodes.

Abstract: This invention relates to the planarization of inductive components by reducing standard coiled designs to single turn designs from which the required parameters are obtained by scaling the length. Single turn designs having magnetic material encircling the conductors along their full length enable the thinnest form. The single turn form also enables the inductive component to be routed according to any shape in the plane or on any conformal surface. The single turn inductors do not need to coil hence there is no overlap necessary in the plane. The planar form allows integration of inductive components with integrated circuits. These inductive components can be embedded in other materials. They can also be fabricated directly onto parts. The differential current transformer by virtue of its fabrication next to a capacitive pick-off enables the preservation of the purity of the signal obtained by taking signal differences close to the transducer and minimizing pick-up from leads.

Abstract: A current transformer includes transformer units combined into a bundle, each of the transformer units including an annular iron core surrounding a bus conductor and a secondary winding wound around the iron core for measuring an electric current flowing through the bus conductor, and a shield winding wound around the bundle of the transformer units. The secondary winding may be provided with an air gap in which no secondary winding is present, located at a portion of the current transformer in a direction of a resultant vector, perpendicular to a line connecting bus conductors neighboring the bus conductor to be measured and passing through the bus conductor to be measured. A second air gap may be provided at the position opposite the air gap of the transformer, relative to the bus conductor to be measured, and the shield winding may be divided into two parts at the air gap and opposite the air gap relative to the bus conductor to be measured.

Abstract: A current transformer assembly comprises a toroidal core and a conductor having a body portion and a mounting portion. The conductor's body portion extends through the aperture of the toroidal core. The mounting portion is positioned for a mechanical and electrical connection between an external conductor and the current transformer. A connection is made between the body portion and the mounting portion wherein mechanical engagement is sufficient to prevent unintended separation of the body portion from the mounting portion and electrical coupling is sufficient to permit the flow of current between the body portion and the mounting portion.

Abstract: A transformer is provided that consists of a primary winding, a secondary winding and a magnetic core. The primary winding is wound directly around the magnetic core, thereby removing the need for a bobbin. By removing the need for the bobbin, the transformer has a large window utilization factor, and associated low profile. As a result, the transformer has a high power to form factor ratio. A method for making the transformer includes the steps of joining two halves of the core before winding the primary winding. Because the half-cores are joined prior to the wrapping of the primary winding, the core provides bobbin functionality. In addition, a header plate is provided for coupling a plurality of leads of a transformer to sources on an integrated circuit board, where the transformer consists of a magnetic core, a primary winding and a secondary winding. The header plate engages the magnetic core, providing a termination path for the wire of the secondary winding.

Abstract: The present invention relates to a gas-insulated current transformer of simple structure for a single-phase or multi-phase switchgear, which transformer can be made in various dimensions and with magnetic cores of various lengths. The transformer comprises at least one support tube carrying three annular cores carrying respective secondary windings. The windings are superposed and disposed coaxially about the tube, and they are held by a clamping strap. The tube and the windings are disposed inside an enclosure defined by two metal plates constituting a bottom closure end plate and a top closure end plate, and by four metal side walls. The end plates are interconnected by link rods disposed in their corners. The two end plates are fixed to the ends of the rods by screws, and the metal side plates are screwed to said rods.

Abstract: A current-detection coil for a current transformer operating by the Rogowski principle has an insulating annular body made of a fiber-reinforced thermosetting plastic and manufactured as a single-piece solid body in a divisible mold. The parting line of a mold serving for manufacturing the annular body is in a flattened region on the outer periphery of the annular body and on a flattened region on the inner periphery. The annular body allows current transformers operating by the Rogowski principle to be manufactured that are capable of measuring in the entire range of currents that may occur and are resistant to mechanical and thermal stresses.

Abstract: A circuit interrupter employing an electronic trip unit utilizes a current transformer assembly containing both air and metal cores on a common load strap for providing sensing current to the electronic trip unit along with supplying operating power to the trip unit electronic components. A two-part plastic housing provides support for the metal core and the sensing coil while further providing thermal transfer of heat generated within the transformer secondary windings out to the load strap.

Abstract: A current transformer assembly has an annular transformer encompassing a busbar where it projects through the wall of equipment. The assembly has an electrically-insulative housing bolted to the equipment wall. The housing has a rear wall with an aperture through which the busbar extends, the transformer being located in a recess between the rear wall of the housing and the front of the equipment wall. The housing is open on its front and has a removable cover plate. The busbar is bolted to the upper surface of a plinth in the housing, which also supports the end of a cable entering through the front wall and bolted to the busbar.

Abstract: The Rogovski coil (1) is provided with a winding (2) applied to a winding support made from an insulating material. It has a central axis (4) and an opening (5), which is enclosed by the winding support and is penetrated by the central axis (4). A particularly homogeneous winding (2) and, associated therewith, very accurate current measurement are achieved by virtue of the fact that a surface, facing the central axis (4), of the winding support is provided with first stops (7), which are distributed on the circumference, extend in the direction of the central axis (4), and divide the winding (2) into winding segments (9). In this case, the spacing between in each case two of the first stops (7) is always an integral multiple of the diameter (D) of the wire forming the winding (2).

Abstract: A device for improving the quality of audio and/or video signals comprises a main electrical circuit comprising an integrated circuit arranged for producing an output pulse signal having a predetermined frequency, and a toroidal inductor having a magnetic core which has a central opening and which is surrounded by a conducting wire, said toroidal inductor being arranged to be powered by said output signal.The device is arranged between a power supply unit and a signal processing unit which is connected by at least a phase- and a neutral conductor to said power supply unit such that said conductors pass through said central opening of said magnetic core, said toroidal inductor creating an alternating magnetic field within its core when it is powered by said output signal, so that said magnetic field induces an electric field which acts on said conductors.

Abstract: A magnetic core-coil assembly generates an ignition event in a spark ignition internal combustion system having at least one combustion chamber. The assembly comprises a magnetic core of amorphous metal having a primary coil for low voltage excitation and a secondary coil for a high voltage output to be fed to a spark plug. A high voltage is generated in the secondary coil within a short period of time following excitation thereof. The assembly senses spark ignition conditions in the combustion chamber to control the ignition event. The assembly is constructed from sub-assembly parts that can be manufactured with existing machines at reasonable cost.

Abstract: A magnetic core-coil assembly generates an ignition event in a spark ignition internal combustion system having at least one combustion chamber. The assembly comprises a magnetic core of amorphous metal having a primary coil for low voltage excitation and a secondary coil for a high voltage output to be fed to a spark plug. A high voltage is generated in the secondary coil within a short period of time following excitation thereof. The assembly senses spark ignition conditions in the combustion chamber to control the ignition event. The assembly is constructed from sub-assembly parts that can be manufactured with existing machines at reasonable cost.

Abstract: A current transformer assembly has three pairs of contacts projecting from the upper and lower surface of a mounting plate. Below the plate, the contacts in each pair are interconnected by a conductor embraced by a toroidal current transformer. The transformers are electrically connected to a connector accessible on the upper surface of the plate. Four mounting bolts project from the upper surface of the plate so that the assembly can be connected to cooperating contacts on an equipment panel. The lower surface of the plate is enclosed by a housing.

Abstract: A toroidal current transformer magnetic shield includes, in one form, a cup portion and a cap portion. Both the cup and the cap are C-shaped, and when the cap is placed over the cup, the cup and cap define a toroidal sensor chamber. The cup portion and the cap portion are constructed of magnetically permeable material, such as iron or steel. A toroidal current transformer is positioned within the sensor chamber, so that the cap and cup enclose, and magnetically shield, the toroidal current transformer.

Abstract: A radio frequency choke for use in a cable television transmission and distribution circuit is disclosed. The radio frequency choke comprises a core of zinc-ferrite material as provided by MMG/NEOSID, Ltd., part number 31P0250012, and a wire coil wound around the core. The coil includes a first lead, a first clockwise winding of N1 turns around the core, the first lead being connected to an input of the first winding, a second counterclockwise winding of N2 turns around the core, a third counterclockwise winding of N3 turns around the core, and a second lead connected to an output of the fourth winding. In a preferred embodiment, there are six turns in the first clockwise winding, five turns in the second clockwise winding, and five turns in the third counterclockwise winding. Moreover, in the preferred embodiment, resonance damping resistors of approximately 2 K.OMEGA. are connected between the windings of the radio frequency choke.

Abstract: An inductor has a winding arranged on a straight magnetic core formed by a plurality of ferrite cylinders disposed in line with one another with a space between adjacent cylinders. The ferrite cylinders are accommodated in a common cylinder made of a molded plastic material which has a helical groove in its outer cylindrical surface. The inductor is used for the injection of a low-frequency current into a cable of a CATV system.

Abstract: A coil for an electrical apparatus such as a transformer is disclosed which includes an electric field control means to minimize flashover or arching at a lead of the coil.

Abstract: A control unit accommodates various equipment, such as a circuit breaker, an electromagnetic switch, a zero-phase current transformer, and an operating transformer. The zero-phase current transformer is generally triangular-shaped to fit more compactly within the control unit. More specifically, the zero-phase current transformer comprises an annular core having a shape which is substantially triangular, wherein the annular core encloses an aperture region having a shape which is also substantially triangular. A primary conductor is disposed within the aperture region, and a secondary conductor is wound on the annular core.

Abstract: Electric current, flowing through a penetration conductor extending through a main housing, is detected by a non-contact current detection unit incorporated in the main housing. Connector housings are provided respectively at those portions of opposite sides of the main housing through which the penetration conductor extends, and opposite end portions of the penetration conductor as connector terminals are disposed within the connector housings, respectively. Each of the connector housings and the associated connector terminal received therein jointly constitute a connector.

Abstract: A small toroidal inductor is mounted by inserting a high valued resistor or a ceramic coil form into the central hole of the toroid. The fine leads of the inductor are then soldered to the much stiffer leads of the part that has been inserted. These stiffer leads may be bent in any desired way, and will hold their shape. This makes insertion easier and is strong enough to withstand the necessary amounts of shock and vibration. The toroid may be glued or otherwise affixed with an adhesive to the resistor or coil form.

Abstract: Electrical isolation which is required between adjacent windings of a device such as a transformer is provided by wrapping a group of individually insulated conductive cores 62, 64, 66, 68 with multiple turns of a thin tape 32. Use of a thin tape rather than solid insulation provides a long creepage path from the cores 62, 64, 66, 68 to adjacent components. The invention can also be applied to components other than transformers.

Abstract: A magnetically variable inductor for high power, high frequency applications which includes a solenoid with a magnetic core therein, disposed coaxially around a conductor for carrying the high power, high frequency signal and a variable current source coupled with the solenoid so that a manipulation of the current through the solenoid results in a variable inductance for said conductor. Also disclosed are additional features of ferrite rings disposed around each end of the magnetic core, a shield disposed between the core and the solenoid, and a sheath disposed around the solenoid.

Abstract: A connecting member is fixedly mounted in a predetermined location so as to penetrate a closed space formed with a ferrite core, and an end of a first lead wire is inserted and connected with an engagement part formed at one end part of the connecting member, and an end of a second lead wire is inserted and connected with an engagement part formed at the other end part of the connecting member, thereby, the trigger winding is formed.

Abstract: A current sensor is provided with a planar member formed within a first opening of the sensor housing and extending inwardly from an inner periphery of the housing. The planar member extends into the first opening and is provided with a second opening through its structure. The second opening formed in the planar member is shaped to permit a portion of an electrical conductor to extend therethrough. The planar member is captured between a portion of the electrical conductor and an external object in order to permit the current sensor to be rigidly retained in a predetermined position relative to the external object. This means of fastening a current sensor to an external object eliminates the need for additional rivets, screws and bolts that would otherwise be required to perform this function.

Abstract: A current transformer device is formed on a ceramic substrate which is provided with a plurality of planar conductive tracks formed on a surface of the substrate where the conductive tracks extend substantially radially from an imaginary point on the surface of the substrate. A structure of permeable material layers is then tape cast or epitaxially formed by vapor deposition of a thick film of magnetic ceramic over the major portion of each of the conductive tracks to form a permeable toroidal core. A lead frame is then placed over the core and a plurality of metal conductors are soldered to each of the respective exposed ends of the metal conductive tracks on the substrate to form a toroidal coil surrounding the toroidal core. The required electrical elements to complete the current transformer device are mounted to a second side of the ceramic substrate and electrically connected to the toroidal coil for powering and/or receiving signals therefrom.

Abstract: A Rogowski coil comprising at least one printed circuit plate provided with a circular cutout, the coil being implemented by rectilinear metal deposits on each of the two faces of the plate and extending along radii such that geometrical projections thereof intersect in the center of said cutout, electrical connections between the radii on one face and those on the opposite face being implemented by plated through holes that pass through the thickness of the plate.

Abstract: A transformer, particularly for use in intrinsically safe systems, has separate first and second magnetic cores mounted in wells in a one-piece elastics housing which serves both as a housing and to electrically segregate the cores. Passing through the housing and through the cores is a wire loop which is turned back and joined outside the housing so as to link the two cores electromagnetically. The cores are preferably toroidal cores carrying windings.

Abstract: For use in a trip unit, a transformer assembly is provided in a compact and cost effective form. The assembly includes a toroidal transformer between a pair of busses, and plastic retainers around a conductor which connects the busses. Each of the plastic retainers are molded as a plastic part which features: a flat portion separating the transformer axially from the adjacent bus, a tubular section attached to the flat portion which protrudes through the center of the transformer and serves to separate it radially from the bus, and a set of ribs protruding from the tubular, flat portions which serve to slightly penetrate the insulation material in the center of the transformer and grip the transformer to prevent it from rotating, and a lip protruding from the flat portion which causes the retainer to stop rotational motion relative to the bus.

Abstract: An induction heater for heating a material is described which has an alternating current carrying conductor 30 extending along an axis of rotation. Mounted about the axis are containers 32 which rotate about the axis and hold the material to be heated. A core 34 is provided encircling the alternating current carrying conductor 30. The core 34 guides the magnetic flux resulting from an alternating current flowing in the conductor 30 to induce a current in the inner sleeve 38 between the conductor 30 and core 34. Current flowing in the inner sleeve 38 is conducted to end plates 40 and 42 and through the containers 32. The containers 32 are heated by the electrical current induced by the magnetic flux in the core 34.

Abstract: A wire-wound bobbin serves as the core of a current transformer. A magnetic material flux path is disposed on the core that encircles the core coincident with the coils of the bobbin at least once and radially encircles the cross section of the core at lest once. The magnetic flux path comprises an assembly of distinct magnetic members positioned on the core and held in place by tape or the like.

Abstract: An AC/DC current detection method that can detect small and large changes in current, by employing a high-frequency excitation current applied to a coil wrapped around an annular iron core. The change in this value is determined for operation in the region of the coercive force of the iron core or as the change in an extreme value thereof.

Abstract: A device for injecting an electromagnetic signal into a conductive cable to be tested, the device being generally cylindrical and having a central bore through which the cable passes. A plurality of concentric cylinders is arranged around the central bore, including an inner conductive cylinder, an intermediate ferromagnetic cylinder and an outer conductive cylinder. The inner and outer cylinders are connected at one end to a signal generator by coaxial cable, and are interconnected at the opposite end.

Abstract: A power conditioner for AC power lines has a choke and capacitor coupled in series across the power lines. The choke comprises a coil terminating in a line, with the line looped back through the coil. The power lines are thereby balanced to provide greater operating efficiency. Capacitors and transient suppressors (e.g., varistors) are used for transient suppression and power factor correction.

Abstract: An AC current sensor comprising a generally C-shaped main coil with a fixed gap between its ends. A pair of compensating coils are positioned at fixed locations in the main coil's gap. The longitudinal axes of the compensating coils lie on an imaginary straight line which extends between the centers of the main coil's ends; and their electrical centers are each spaced the same distance from their respective ends of the main coil. A compensating coil gap is defined between the electrical centers of the compensating coils. The main coil defines a measuring recess in which the sensed AC current carrying conductor is located when a measurement is taken. When the ratio of the size of the main coil gap to the size of the compensating coil gap is equal to the square root of three, the AC current sensor's accuracy and outside signal rejection increase most rapidly with increased distance of the sensed AC current carrying conductor from the compensating coil gap, and the AC current sensor's size can be minimized.

Abstract: A device for measuring electric current includes a toric core having a gap that establishes a pair of opposed end faces, and a continuous conductor having terminal ends and wound around the core in contiguous turns forming a toric solenoid interrupted by the gap. The solenoid has first and second ends adjacent the respective end faces of the core, and the conductor at each end of the solenoid passes through the core and extends along the axis thereof from the opposed end faces of the core such that the terminal ends of the conductor are located diametrically opposite the gap. A first compensation coil is serially connected to said first end of the solenoid such that the first coil overlies the first end of the solenoid to which the first compensation coil is connected.

Abstract: A current sensing element is included as an integral part of a magnetic component by mounting a toroidal magnetic core having a current sensing winding into a receptacle of a winding bobbin of the magnetic component. This eliminates a need for a separate board mounted current sensing winding thereby saving circuit board space and reducing overall parts count on the circuit board, and circuit assembly costs.

Abstract: The problem of effectively and quickly detecting fault conditions in an electromotive machine (10) is solved using a current transformer assembly (28) having a neutral lead (44). The neutral lead (44) comprises a single piece copper strap (80) having laterally extending strips or posts (81-83) provided for connection to the neutral end conductors (31-33) of armature windings (22 and 24). The strap (80) is punched and bent into shape to include the three neutral posts (81-83). Each neutral post (81-83) carries a current transformer (46-48).

Abstract: The current converter or transformer component of a high voltage measurement transformer comprises a primary lead or conductor which is surrounded by secondary windings or optical conducting elements. The primary and secondary components of the current converter or transformer component are housed in a casing having an integrally formed entry duct for the secondary leads. The secondary components of the current converter or transformer component are surrounded by plastic or synthetic insulation material. This insulation material or insulation also surrounds a channel for the secondary leads extending completely through the entry duct. The primary lead or conductor is provided with connecting flanges at both ends for mechanically or electrically connecting the high voltage measurement transformer to a high voltage or high power circuit breaker or similar device.

Abstract: An electromagnetic shield for electromagnetic apparatus comprises a plurality of shield coils (2-7) wound intermittently on a looped magnetic core (11). Same polarity terminals of the shield coils are connected to form current paths which prevent external fluxes .phi..sub.1, .phi..sub.2 from entering into the core.

Abstract: A current detection device has an annular dielectric substrate with a thin (e.g., less than one skin depth at maximum frequency) resistive foil laid down on the substrate outer surface and extending completely thereabout. Annular metal rims are affixed to the substrate edges respectively contacting the metal foil or film. A conductive strip of appropriate dimensions is received onto the outer edges of the metal rims and extends about the complete circumference of the rims. A resistive material is used to secure the conductive strip to the edges of the rims so that the entire resistance of the strip and resistance material exceeds that of the sensing metal foil to prevent shorting out of the foil.