Abstract: In the magnetic core including a first leg portion around which a wire is wound, a second leg portion for circulating a magnetic flux generated in the first leg portion, and a web portion connecting the first leg portion and the second leg portion, a magnetic gap is provided in a rear area extending from the root of the first leg portion. With the magnetic gap, a magnetic flux leaking outwardly from a rear area extending from the root of the first leg portion is drastically reduced.

Abstract: A pickup device has a core to which a coil is wound about. The core has a body formed by laminating a plurality of plates having a predetermined shape. Eddy currents produced by leakage flux is suppressed at the ends of the core. This is achieved by laminating a plate, which has a certain shape and is made of a material having a higher electric resistance value than the body, to the ends of the body. The generation of eddy currents may also be suppressed by providing notches at the ends of the core to obstruct the formation of a magnetic circuit at the ends. As another option, space may be provided at the ends of the core to disconnect the path of eddy currents.

Abstract: A coil insert for use with a secondary coil portion of a charging system for an electric toothbrush. The secondary coil is positioned within the handle of the toothbrush. The insert includes a first portion which is configured to fit in the central opening of the secondary coil and a base portion which extends out from the secondary coil. The insert has enough weight, approximately one ounce, to significantly dampen the vibrational effects caused by operation of the toothbrush. The steel peen is sufficiently small so as to not absorb any energy from the charging coil during operation of the charging system and to increase coupling efficiency between the primary and secondary charging coils.

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 winding structure of a flyback transformer comprises a plurality of layers of a coiled-circuit pattern sheet. The coiled-circuit pattern sheet includes a tubular sheet, a coiled-circuit pattern formed around the tubular sheet, and a magnetizable core inserted into the tubular sheet. The coiled-circuit pattern sheet and the magnetizable core have a shape of an elongated flexible strip. The coiled-circuit patterns are electrically connected in series with each other, and the magnetizable cores are connected with each other by a conductive binder and so on, so as to form a closed circuit in a zig-zag formation.

Abstract: The measurement device for generating a measurement signal from an object without physical contact with the object includes a magnetizable plastic coil body and at least one coil arranged on the coil body and through which a current flows during generation of the measurement signal. The coil body can be part of a one-piece injection molded plastic part consisting of a magnetizable plastic material. In a preferred embodiment the one-piece injection molded magnetizable plastic part consists of ring-like mounting element and a sleeve-like extension with a exterior circumferential groove for the coil or coils which acts as the magnetizable plastic coil body. The magnetizable plastic substance can be a polyamide plastic substance filled with a weakly magnetizable material such as an iron-cobalt powder.

Abstract: An annular core for a choke, in particular for radio interference suppression of semiconductor circuits by the phase control method, includes two different soft magnetic materials. One material is crystalline and is formed as an annular-core-shaped trough which receives the other material that is in the form of amorphous and/or nanocrystalline particles. The annular core which is thus formed can then be surrounded by a coil, that is connected in series with the consumer by phase control.

Abstract: A magnetic core includes a body made of polycrystalline ceramic and at least one localized gap made of a composite magnetic material. The gap may be preferably fixedly joined to the body by bonding or molding. The magnetic core has applications in inductors or transformers. The inductor preferably has a coil located on the body, which coil is preferably made of multistranded enameled wires.

Abstract: A low profile reactor or inductor with a spiral type of winding which conducts a high level of current for its allotted size. The present invention provides a unique two piece bobbin design in order to produce a reactor of this type in a small space with small dimensional tolerances. The two piece bobbin is designed to provide a connection to the interior terminal end of the reactor coil, which is normally difficult to accomplish because of the limited small size and area. A first bobbin piece defines a first bobbin flange, and the second bobbin piece defines a center post, providing a cylindrical winding surface, and a second bobbin flange. The center post is provided with a first recessed groove in the winding area, and the second bobbin flange is provided with a second recessed groove. A start terminal is positioned in the first and second recessed grooves below the surfaces thereof.

Abstract: A bias coil assembly for use in combination with a magnetomotive generator such as employed in a magneto-optical disc drive. The assembly includes a return yoke having a body portion and a tip having a predetermined thickness and extending beyond the body portion. A winding for receiving electric current is wound around the body portion of the yoke so that the winding is contained below the tip. A first plate is disposed on the winding and includes at least one heat-radiating finger extending substantially around the winding without increasing the vertical height of the assembly. A second plate is disposed on the winding in a magnetic circuit with the first plate and the return yoke so that when the winding is connected to a source of power, the tip receives lines of magnetic flux that are channeled through the body portion while the at least one flange radiates thermal energy thereby produced.

Abstract: A method and apparatus to amplify the magnetic field in an electromagnetic circuit is provided. Amplification factors of several orders of magnitude may be obtained. The system is applicable to a number of different systems, including melt levitation and electromagnetic pumping and propulsion. One embodiment of the invention uses a non-conducting permeable core wound around a dielectric core. An alternating voltage source is connected to a solenoid which is wound around a section of the permeable core. The permeable core has a gap within which a flux concentrating cold crucible is provided. Melt levitation processing takes place within the cold crucible.

Abstract: An inductive coupler forming a closed magnetic circuit by mating a primary core assembly having a primary winding and a secondary core assembly having a secondary winding for transferring electrical power from the primary winding to the secondary winding by electromagnetic induction. A thin magnetic protective sheet having high permeability is attached to the mating surfaces of at least one of said primary and secondary core assemblies or placed to be held by the core assemblies. The magnetic sheet can protect the mating surfaces of ferrite cores, if such cores are used, from breakage by absorbing and dispersing the shock of impact caused when the mating surfaces are abutted against each other to close the cores. Provision of a slit or slits in the magnetic protective sheet can reduce eddy currents flowing in the magnetic sheet.

Abstract: An inductive charging coupler for use in an inductive charging system that minimizes damage thereto caused by shock. The charging coupler comprises a housing, and a magnetic core disposed in the housing that is comprised of a plurality of sections. A primary winding is disposed around the magnetic core, A current conductor is coupled to the primary winding for coupling current thereto. By employing smaller sections of ferrite material to form the magnetic core, there is less potential for encountering broad differences in the crystal structure of the ferrite material. These structural differences can cause the ferrite material to be more prone to crack or shatter under stress conditions, such as if the coupler is dropped during use. Also smaller ferrite pieces are lighter than a single piece of ferrite material, which causes lower distributed loads due to a shock.

Abstract: A choke call includes a bobbin, a pair of windings wound around the bobbin, and two magnetic cores. The bobbin has a rectangular barrel in which a circular hole is defined. The two magnetic cores are partly inserted into the hole of the barrel. The hole is offset from the central axis of the barrel. A central collar extends perpendicular to and at the central portion of the barrel. Two end collars extend beyond and parallel to opposite ends of the barrel. The thickness of the central collar is approximately two times greater than that of the end collars. The magnetic cores collectively form an opening. Within the opening, the gap between the outer periphery of the central collar and the magnetic cores is greater than that between the outer periphery of the end collars and the magnetic cores. A part of the magnetic cores within the hole has a circular or rectangular cross-section.

Abstract: Disclosed herein is a planar magnetic element comprising a substrate, a first magnetic layer arranged over the substrate, a first insulation layer arranged over the first magnetic layer, a planer coil formed of a conductor, having a plurality of turns, arranged over the first insulation layer and having a gap aspect ratio of at least 1, the gap aspect ratio being the ratio of the thickness of the conductor to the gap between any adjacent two of the turns, a second insulation layer arranged over the planar coil, and a second magnetic layer arranged over the second insulation layer. When used as an inductor, the planar magnetic element has a great quality coefficient Q. When used as a transformer, it has a large gain and a high voltage ratio. Since the element is small and thin, it is suitable for use in an integrated circuit, and can greatly contribute to miniaturization of electronic devices.

Abstract: A choke coil which functions not only to eliminate common mode noise but also to eliminate differential mode noise. A couple of coils are wound around a circular first core and a second core which is disposed inside the circular first core. The second core has a circular frame and a bridge which is laid in the frame. The first core may be easy to become magnetic saturation but is made of a material with a large magnetic permeability, and preferably a material with a relative magnetic permeability of several thousand, such as ferrite and amorphous. The second core is made of a material which is hard to become magnetic saturation, and preferably a material with a relative magnetic permeability of some scores to several hundred, such as dust core.

Abstract: A differential type sensing unit which includes a winding core having a winding shaft is described. In one embodiment, a post extends from the winding shaft and is located intermediate first and second winding ends of the winding shaft. The post facilitates reversing the winding direction of a conductor wound on the winding shaft. The conductor is wound such that the sensing unit includes a first sensing coil and a second sensing coil formed in a series opposing configuration. The sensing unit may be integrated with a driving unit to include driving coils formed over the top of the sensing coils.

Abstract: A sum current transformer that acts on a protective switch via an amplifier has a core of a solid metallic material composed of an alloy having more than 40% nickel, so that it can be implemented mechanically solid even given small dimensions. The temperature dependency of the arrangement caused by the ohmic resistance of the winding is compensated by the diminishing eddy currents in the core given increasing temperature, so that the smallest dimensions can be realized for the aggregate current transformer.

Abstract: In accordance with the invention, a variety of magnetic devices can be made up of two or more low-profile surface components on a printed circuit board. For example, low profile devices comparable to gapped U-core pair and gapped E-core pair inductors or transformers can be formed of two and three components, respectively, and four components can be assembled into a gapped toroidal transformer or inductor. The components can be made in form for both linear and non-linear inductors.

Abstract: A common mode choke has a generally rectangular ferrite body for surface mounting on a printed circuit board. First and second spaced apart slotted openings extend vertically between the top face and the bottom face of the ferrite body. At least one pair of electrical conductors extend along parallel paths from the bottom face through the first slotted opening to the top face, along a portion of the top face, and back down through the second slotted opening to the bottom face. One pair of opposing side faces preferably has lower portions extending outwardly past a plane of the bottom face to thereby serve as a support to mount the bottom face of the ferrite body in spaced relation from the circuit board. The electrical conductors may then extend outwardly from the bottom face of the ferrite body for electrical connection through corresponding openings of a circuit board or extend laterally outwardly for electrical connection to corresponding portions of the circuit board in a gull wing configuration.

Abstract: In A method of manufacturing a solid inductor having an inner conductor formed by passing through a magnetic, material. A vitreous diffused material is applied to the surface of the magnetic material, and the diffused material is diffused into the magnetic material by heat treatment, to form a diffusion layer exhibiting low permeability. The thickness of this diffusion layer is adjusted, thereby to make it possible to adjust the inductance value of the solid inductor as well as to improve resistance to humidity of the solid inductor.

Abstract: The inductor has a winding arranged on a straight magnetic core formed by, for example, a ferrite cylinder (4) accommodated in a cylinder (1) made of a moulded plastics material and having a longitudinal groove in its outer cylindrical surface, in which groove a bar (2) of an electrically resistive material is mounted, the bar being fixed underneath the winding wire (3). The inductor is used for the injection of low-frequency current into a cable of a CATV system.

Abstract: A ferromagnetic material (18,20) in ink or tape form is sinterable using a same firing profile as and has approximately the same thermal shrinkage characteristics as low-temperature-cofired-ceramic (LTCC) tape, and is chemically non-reactive therewith. The ferromagnetic material (18,20) is applied to the surfaces of LTCC tape sheets (12,14,16) to form desired elements such as cores for inductors (22) and transformers and magnetic shields. Ferromagnetic vertical interconnects (vias) (54) can be formed by punching holes (56) through tape sheets (46) and filling them with ferromagnetic ink. The tape sheets (12,14,16) and ferromagnetic elements (18,20) are laminated together and cofired to form an integral structure (10). Ferromagnetic and non-magnetic components (114) can be fabricated separately and inserted into cavities (104a,-106a,108a) in tape sheets (104,106,108) prior to cofiring.

Abstract: A composite winding type inductor having a stacked-layer structure formed by stacking a plurality of sets of electrically conductive strips for forming plural sets of coils alternately with a plurality of electrically insulting members. The electrically conductive strips in each of the sets are connected to the adjacent ones by way of edges of the electrically insulating members to thereby form a coil. A plurality of the coils thus formed turn around substantially a generally common axis. At least two of the plural sets of the electrically conducting strips are stacked in layers in such a manner as to follow spiral paths in the directions apposite to each other. The coils formed by at least two sets of the electrically conductive strips are connected to each other at least at one of a start end portion, an intermediate portion and a terminal end portion of the coil.

Abstract: An inductor which has a ferrite core and a coil wound around the ferrite core. The ferrite core is coated with borosilicate zinc glass. The ferrite core is produced by: adding a low-temperature-sintered oxidized metal, such as BiO.sub.2 and PbO, and a resin binder to ferrite powder of Mn, Fe, Co, Ni or the like; mixing the materials together; compression molding the mixture; and sintering the molded article in a low temperature.

Abstract: A common mode choke coil has a couple of coils, a magnetic frame in which the coils are encased, the magnetic frame forming closed magnetic circuits around the respective coils, and a magnetic core which pierces through the magnetic frame. The frame is made of an insulating magnetic material which has a relative magnetic permeability of more than one, preferably two through some scores. For example, a mixture of ferrite powder of Ni--Zn and resin is used as the material of the frame. The core is made of a material which has a relative magnetic permeability of preferably several thousands, such as ferrite and amorphous.

Abstract: Magnetic components are fabricated as monolithic structures using multilayer co-fired ceramic tape techniques. Fabrication of these magnetic components involves constructing multiple layers of a magnetic material and an insulating non-magnetic material to form a monolithic structure with well defined magnetic and insulating non-magnetic regions. Windings are formed using screen printed conductors connected through the multilayer structure by conducting vias.

Abstract: A common mode choke has a generally rectangular ferrite body for surface mounting on a printed circuit board. First and second spaced apart slotted openings extend vertically between the top face and the bottom face of the ferrite body. At least one pair of electrical conductors extend along parallel paths from the bottom face through the first slotted opening to the top face, along a portion of the top face, and back down through the second slotted opening to the bottom face. One pair of opposing side faces preferably has lower portions extending outwardly past a plane of the bottom face to thereby serve as a support to mount the bottom face of the ferrite body in spaced relation from the circuit board. The electrical conductors may then extend outwardly from the bottom face of the ferrite body for electrical connection through corresponding openings of a circuit board or extend laterally outwardly for electrical connection to corresponding portions of the circuit board in a gull wing configuration.

Abstract: A choke coil apparatus for an electromagnetic range comprises an improved ferrite core, so as to prevent an increasing in temperature of the choke coil. The ferrite core in a multiangular bar-shape forms a plurality of ventilation spaces between the choke coil and the ferrite core, thereby air-cooling the choke coil by the air flowing in the ventilation space.

Abstract: A current controlled variable inductor comprises a magnetically saturable E" core having outer limbs each joined to a center limb by connecting limbs. A staggered series of flux bridges and air gaps are formed into alternating sides of the outer limbs. A bias winding on the center limb magnetically couples a direct current into the core to vary the inductance of a signal winding on the outer limbs. A secondary winding magnetically couples an output voltage from the core for application of the inductor as a tunable transformer.

Abstract: A current sensor having a single-turn primary coil where the secondary coil is wound on a straight core that is bent so that diametrically opposed ends are electrically, mechanically and magnetically connected to form the primary coil.

Abstract: A current transformer comprising a primary conductor means 20, secondary conductor means in the form of a first and second coil 21, 22 connected to ensure common-mode rejection of emf induced by external disturbing magnetic fields, and magnetic coupling means defined by first and second magnetic plates 23, 24 and first and second ferrite elements 25, 26 arranged within the first and second coils 21, 22, the elements 25, 26 contacting and physically separating the first and second plates 23, 24, thereby defining a closed magnetic circuit with the plates.

Abstract: The choke coil comprises a bead of a soft-magnetic material in which a number of ducts extend in parallel. An electrically conductive wire comprising fee ends is accommodated in the ducts. The choke coil comprises means for shielding a portion of the turn which extends outside the ducts. To this end, for example an electrically insulating housing is arranged around the bead. The housing consists of two approximately cylindrical portions, each of which comprises a substantially closed end face which is situated on a first end portion. The cylindrical portions are axially slid over the bead with their second open end portion fitting one into the other. In each end face there is provided at least one opening for feeding out the wire. When the choke coil is also provided with electrically insulating caps having a wire passage in the prolongation of the axis of the bead, the wire fed out will be oriented along said axis.

Abstract: A ferrite chip bead includes a ferrite substrate, a plurality of outer electrodes formed at opposite sides of the ferrite substrate, and a plurality of conductive leads each extending transversely through the ferrite substrate and having opposite ends protruded outwardly of opposite side surfaces of the ferrite substrate and connected to corresponding outer electrodes. Conductive leads are embedded in the ferrite substrate by introducing conductive leads in a central portion of a nozzle for extruding the ferrite substrate such that the conductive leads are embedded in the ferrite substrate being extruded, or by introducing conductive leads between ferrite substrate sheets being fed to be bonded together for forming the ferrite substrate such that the conductive leads are interposed between the ferrite substrate sheets being bonded. The ferrite chip has no tendency for outer electrodes to short-circuit from the ferrite substrate upon carrying the chip bead on a circuit board.

Abstract: In a solid inductor having an inner conductor formed by passing through a magnetic material, a vitreous diffused material is applied to the surface of the magnetic material, and the diffused material is diffused into the magnetic material by heat treatment, to form a diffusion layer exhibiting low permeability. The thickness of this diffusion layer is adjusted, thereby to make it possible to adjust the inductance value of the solid inductor as well as to improve resistance to humidity of the solid inductor.

Abstract: Magnetic components are fabricated as monolithic structures using multilayer co-fired ceramic tape techniques. Fabrication of these magnetic components involves constructing multiple layers of a magnetic material and an insulating non-magnetic mataerial to form a monolithic structure with well defined magnetic and insulating non-magnetic regions. Windings are formed using screen printed conductors connected through the multilayer structure by conducting vias.

Abstract: An improved electro/mechanical connector through which multi-media electrical signals are transported includes a first port with resilient contact tongues, a second port for supporting a coaxial assembly and a third port coupled to a circuit module which receives the multi-media electrical signals on an input terminal splits the multi-media electrical signals into broadband signals which are routed to the coaxial assembly and baseband signals which are routed to the first port. The circuit module also receives broadband signals and baseband signals from the coaxial assembly and first port respectively combines them into the multi-media signals which are outputted on the input terminal.

Abstract: An electromagnetic apparatus such as a transformer or a single winding inductor is provided with a cooling arrangement. The apparatus has a magnetic core and a coil winding disposed about and carried by a leg of the core. The magnetic core has legs connected to the leg that carries the coil winding and these legs have flat surfaces that directly contact a flat surface of a metallic heat sink to thereby provide a direct heat conductive path from the legs to the heat sink. Heat generated in the coil winding is transferred to the heat sink via the leg that carries the coil winding and then to the heat sink via the legs that directly engage the heat sink. Heat generated in the magnetic core due to hysteresis or eddy current loss is also transferred to the heat sink.

Abstract: A transducer is disclosed for detecting an electrical pulse from a circuit and for generating an output signal in response to each pulse. The transducer includes a first electric coil having two ends adapted for connection with the circuit and a second electric coil having two ends on which the output signal is generated. The coils are coaxially wound together and a rod constructed of a ferromagnetic material is positioned through the rod. A housing also constructed of a ferromagnetic material includes two spaced end portions which contact the opposite ends of the rod. The housing also includes locking tabs which engage and lock the housing to opposite ends of the rod.

Abstract: The novel magnetic core structure of this invention provides a combination of large differential type inductance and some common mode type inductance while accommodating common mode dc current in two parallel planar conductors such as bus bars or printed circuit lands. This combination of desirable functions is accomplished by incorporating both gapped and ungapped magnetic flux paths into a single core structure. The core structure is composed of two outer posts, two inner posts, and four link segments. The two inner posts of the present core are located in the position of the center leg of a tradiational E--E core structure. Unlike a conventional E--E core, the structural arrangement of the two inner posts provides both a gapped and an ungapped magnetic flux path. The ungapped magnetic flux path travels in a figure eight pattern, encircling each of the windows of the E--E core in one of the loops of the figure eight.

Abstract: An inductive device comprises a soft magnetic core which consists of two E-shaped core halves (1), each of which comprises three parallel limbs (5, 7) which are interconnected by a yoke (9). The core halves (1) are arranged against one another by way of the free ends of the limbs (5, 7), a coil former (3) being provided around the central limbs (7). The outer limbs (5) extend between an upper boundary plane (25) and lower boundary plane (27), which planes extend parallel to the longitudinal directions of the limbs (5, 7) and the yokes (9), the distance between said planes being determined by the height (x) of the outer limbs (5) which is greater than the height (y) of the central limbs (7).

Abstract: The invention relates to a sintered transformer core of MnZn-ferrite material, the initial permeability of which ranges between 10 and 1000. Said transformer cores preferably have an average particle size which ranges between 0.05 and 2.0 .mu.m. The transformer cores according to the invention exhibit surprisingly low overall losses when operating in the frequency range of 2 MHz and higher. Such transformer cores can be very advantageously used in transformers operated in said frequency range, such as SMPS transformers.

Abstract: A folded conductive film winding transformer provides a plurality of poles and enables increased turns ratios or power handling capacity in structures which must meet severe height limitations.

Abstract: A core for an integrated magnetic power converter includes a continuous magnetic structure having first and second legs and a magnetic flux conducting path therebetween. A primary winding is disposed on the first leg. A first secondary winding is disposed on the first leg. A second secondary winding is disposed on the second leg. The first leg has a cross-sectional area which is greater than the cross-sectional area of the second leg.

Abstract: A high power, high frequency inverter has series/parallel resonant inverter elements and employs MOS controlled thyristors (MCTs) in the switching circuit. The resonant inverter elements include a split inductor for reducing peak voltage across the switches. A fault protection circuit cause the power interruption for a short interval before restarting the circuit. High current density is achieved by means of multilayer ceramic chip capacitors and gap ferrite planar inductors.

Abstract: A dual-permeability magnetic core structure is provided for use in small, high-frequency inductors and transformers. The dual-permeability core encloses a winding window containing planar windings and comprises high-permeability and low-permeability sections positioned to produce a highly uniform, or uniformly varying, magnetic field on the winding surfaces. The dual-permeability core products low winding losses and a low AC-to-DC resistance ratio. Fabrication of the dual-permeability core involves a method of controlling the permeability of a magnetic material and a methd of combining structures of two different permeability values.

Abstract: A lamination type inductor has a plurality of ferrite sheets assembled one above the other and laminated together, the uppermost and lowermost sheets being end sheets having lead-out conductor patterns thereon and conductor patterns on the surfaces of the end sheets which face each other which are connected to the lead-out conductor patterns and which are for connection to conductor patterns on intermediate sheets, and a plurality of intermediate ferrite sheets, each having a conductor pattern on one surface thereof which corresponds to a 0.25 turn of an inductor coil and a conductor pattern on the other surface which corresponds to a 0.5 turn of an inductor coil, each ferrite sheet having an opening therethrough through which the conductor patterns of the 0.25 and 0.5 turn are electrically connected to form a 0.75 turn of an inductor coil on each ferrite sheet.

Abstract: An ignition coil for developing spark plug firing voltages. The magnetic current for the coil comprises an axially extending core that joins axially spaced annular parts. The core and parts can be formed of iron particles in a binder of electrical insulating material. A primary winding is disposed about the core and a secondary winding is disposed about the primary winding. An axially extending circular part that is formed of magnetic material is positioned to provide air gaps with outer surfaces of said annular parts. The circular part forms a shield that increases the capacitance of the secondary winding. The total stored magnetic energy does not vary substantially with variations in air gap length. The cross-sectional area A of the air gap is large as compared to the length L of the air gap so that the ratio A/L does not vary much with variations in L.

Abstract: A motor controller or contactor is disclosed which utilizes a non-saturating current transformer for sensing the amount of current flowing in the electrical conductor connected to the contactor. The current sensor is made of homogeneous sintered powdered metal having evenly distributed microscopic air gaps therein which increase the reluctance of the magnetic circuit but resist the influence of stray magnetic flux. This increased reluctance prevents magnetic saturation over a wide range of input current and allows the secondary of the transducer to produce a voltage which is proportional to the derivative of the primary current, that is the current being sensed by the transducer. The aforementioned voltage is linearly proportional to the derivative of the current over a wide range of primary current values. This voltage is integrated to produce an output signal which is directly proportional to the aforementioned primary current over the wide range of current values.

Abstract: A stator assembly for an alternating current generator. The stator core is a one-piece molded part that is formed of iron powder having a particle size in a range of about 10 to 250 microns. The powder is bound together by a thermoplastic material which covers the particles and which serves to insulate the particles from each other. The particles may be coated with phosphorus and the phosphorus layer overcoated with the thermoplastic material. A three-phase output stator winding is carried by the core and has conductor portions located in core slots.