Abstract: A magnetic core includes a first core having a recess and a second core, which has a first end portion and a second end portion both held in contact with the first core and forms a closed magnetic path with the first core. The second core is formed of material having a lower magnetic permeability and a higher saturation magnetic flux density than those of the first core. The second end portion includes a distal surface having an area larger than the cross-sectional area of the first end portion in a direction perpendicular to the direction in which a magnetic flux flows in the closed magnetic path. The distal surface of the second end portion is held in contact with the first core and the first end portion is engaged with the recess in the first core.

Abstract: An electronic component has a drum-shaped core member constituted by an assembly of soft magnetic alloy grains containing iron (Fe), silicate (Si) and chromium (Cr), a coil conductive wire wound around the core member, a pair of terminal electrodes connected to ends of the coil conductive wire, and an outer sheath resin part covering the wound coil conductive wire and constituted by a magnetic powder-containing resin; wherein there is an area where only the resin material in the magnetic powder-containing resin is permeated from the surface of the core member to a specified depth.

Abstract: A coil-type electronic component has a coil inside or on the surface of its base material and is characterized in that: the base material is constituted by a group of grains of a soft magnetic alloy containing iron, silicon and other element that oxidizes more easily than iron; the surface of each soft magnetic alloy grain has an oxide layer formed on its surface as a result of oxidization of the grain; this oxide layer contains the other element that oxidizes more easily than iron by a quantity larger than that in the soft magnetic alloy grain; and grains are bonded with one another via this oxide layer.

Abstract: A micromagnetic device includes a first insulating layer formed above a substrate, a first seed layer formed above the first insulating layer, a first conductive winding layer selectively formed above the first seed layer, and a second insulating layer formed above the first conductive winding layer. The micromagnetic device also includes a first magnetic core layer formed above the second insulating layer, a third insulating layer formed above the first magnetic core layer, and a second magnetic core layer formed above the third insulating layer. The micromagnetic device still further includes a fourth insulating layer formed above the second magnetic core layer, a second seed layer formed above the fourth insulating layer, and a second conductive winding layer formed above the second seed layer and in vias to the first conductive winding layer. The first and second conductive winding layers form a winding for the micromagnetic device.

Abstract: The disclosed embodiments relate to a power supply for a portable electronic device. The power supply includes a power source and a nonlinear inductor. The nonlinear inductor includes a first core and a second core connected in series to the first core, wherein the second core has a higher permeability than the first core.

Abstract: An Fe-based amorphous alloy of the present invention has a composition formula represented by Fe100-a-b-c-x-y-z-tNiaSnbCrcPxCyBzSit, and in the formula, 1 at %?a?10 at %, 0 at %?b?3 at %, 0 at %?c?6 at %, 6.8 at %?x?10.8 at %, 2.2 at %?y?9.8 at %, 0 at %?z?4.2 at %, and 0 at %?t?3.9 at % hold. Accordingly, an Fe-based amorphous alloy used for a powder core and/or a coil encapsulated powder core having a low glass transition temperature (Tg), a high conversion vitrification temperature (Tg/Tm), and excellent magnetization and corrosion resistance can be manufactured.

Abstract: An electronic device including a core, at least a wire and a magnetic material is provided. The core includes a pillar, a top board and a bottom board. The pillar is disposed between the top board and the bottom board. An area of the top board is smaller than an area of the bottom board. A winding space is formed among the top board, the bottom board and the pillar. The wire is winded around the pillar and located in the winding space. The magnetic material fills the winding space to encapsulate the wire. The magnetic material includes a resin and a metallic powder, wherein an average particle diameter of the magnetic powder is smaller than 20 ?m.

Abstract: A flux concentrator and method for manufacturing a flux concentrator is provided. The method can include combining powdered soft magnetic material, a binder, a solvent, a internal lubricant; mixing the materials to create a mixture, evaporating the solvent from the mixture, molding the mixture to form a flux concentrator, and curing the flux concentrator. The flux concentrator may be laminated and broken into multiple pieces, which makes the flux concentrator more flexible. Breaking the flux concentrator does not significantly affect the magnetic properties. Since the permeability of the binder is very similar to that of air, adding tiny air gaps between the fractions is not significantly different than adding more binder.

Abstract: Provided is a reactor having a small size with consideration of loss reduction. A reactor 1A includes a coil 10 and a magnetic core 20. The coil 10 is formed by winding a wire. The magnetic core 20 includes an internal core portion 21 that is inserted through the coil 10 and a couple core portion 23 that is coupled to an end of the internal core portion 21 and that covers an outer periphery of the coil 10. The core portions 21 and 23 form a closed magnetic path. An interposed core portion 25 is disposed between the coil 10 and the internal core portion 21. The reactor 1A satisfies 0<S2/S1<0.15, where S1 is an inner cross-sectional area of the coil 10 and S2 is a cross-sectional area of the interposed core portion 25; and satisfies B1>B2 and B1>B3, where B1 is a saturation magnetic flux density of the internal core portion 21, B2 is a saturation magnetic flux density of the couple core portion 23, and B3 is a saturation magnetic flux density of the interposed core portion 25.

Abstract: A planar magnetic component and a method for manufacturing the same are provided. The planar magnetic component includes a substrate and a magnetic structure embedded in the substrate; wherein the magnetic structure includes a ferromagnetic material layer and at least one first hard protective layer disposed on a first surface of the ferromagnetic material layer to prevent the ferromagnetic material layer from being breaking in a pressing process.

Abstract: A composite iron-based powder suitable for soft magnetic applications such as inductor cores. Also, a method for producing a soft magnetic component and the component produced by the method.

Abstract: The disclosed reactor has a case and a cylindrical molded coil assembly which is disposed inside of the case and which is formed by covering a coil with a resin, wherein the coil assembly is sealed by an iron powder mixed resin to which iron powder has been admixed. The reactor has a pillar provided as a single body with the case, and one or multiple ring-shaped core members. The ring-shaped core members are disposed outside the outer surface of the pillar such that the pillar is inserted inside the inner surface of said ring-shaped core members, and the assembly coil is disposed outside the outer surface of the ring-shaped core members such that the ring-shaped core members are inserted inside the inner surface of said coil assembly. The ring-shaped core members are sealed by means of the aforementioned iron powder-mixed resin.

Abstract: Inductor core including: a base core portion having a first surface and an opposite second surface; an inner core portion extending from the first surface in a direction transverse to the first surface; an outer core portion extending, in the direction transverse to the first surface, from the first surface to an end surface of the outer core portion, the outer core portion at least partly surrounding the inner core portion, thereby forming a space around the inner core portion for accommodating a winding; wherein the first surface includes a recess for accommodating a connection portion of the winding, said recess extending at least a part of a distance between the inner core portion and the outer core portion, and wherein the outer core portion presents a slit extending from said end surface towards the recess, and wherein the second surface comprises a first protrusion oppositely arranged to the recess.

Abstract: A magnetic core including a winding core portion; and a flange portion provided on the axial end side of at least one of the winding core portion, wherein the flange portion is formed such that contour line OL1 of cross-section P, of the flange portion, which becomes perpendicular with respect to the axis line of the winding core portion forms a shape of a first irregular convex polygon which is substantially a non-regular polygon and also a convex polygon, and the contour line OL1 contacts with respect to all of sides Sb1, Sb2, Sb3 and Sb4 which are the four sides of a first circumscribed rectangle which becomes minimum within imaginary rectangles circumscribed with the contour line OL1 and also, the contour line OL1 includes side Sa1 and side Sat which respectively overlap with portions of respective ones of the side Sb1 and the side Sb2.

Abstract: A magnetic core is provided for an integrated circuit, the magnetic core comprising: a plurality of layers of magnetically functional material; a plurality of layers of a first insulating material; and at least one layer of an secondary insulating material; wherein layers of the first insulating material are interposed between layers of the magnetically functional material to form subsections of the magnetic core, and the at least one layer of second insulating material is interposed between adjacent subsections.

Abstract: A method for manufacturing a spiral coil, the method including: forming a solenoid having a diameter larger than a length by spirally winding an insulated electric wire; forming a spiral coil having folded corners by folding four corners in a circumference direction with respect to the solenoid; fixing the folded corners of the spiral coil; and fixing two terminal portions corresponding to start and end points of the spiral coil to a fixing module. According to the method, a thin and long spiral coil having folded corners is easily manufactured by using a general insulated electric wire. In addition, the spiral coil manufactured by using such a method is applicable to a surface radio frequency (RF) coil optimized for various applications of an electro-magnetic acoustic transducer (EMAT) and enables easy access to an optimized transducer.

Abstract: The invention discloses a soft magnetic amorphous alloy and a soft magnetic nanocomposite alloy formed from the amorphous alloy. Both alloys comprise a composition expressed by the following formula: (Fe1-x-yCoxMy)100-a-b-cTaBbNc where, M is at least one element selected from the group consisting of Ni and Mn; T is at least one element selected from the group consisting of Nb, W, Ta, Zr, Hf, Ti, Cr, Cu, Mo, V and combinations thereof, and the content of Cu when present is less than or equal to 2 atomic %; N is at least one element selected from the group consisting of Si, Ge, C, P and Al; and 0.01?x+y?0.5; 0?y?0.4; 1?a?5 atomic %; 10?b?30 atomic %; and 0?c?10 atomic %. A core, which may be used in transformers and wire coils, is made by charging a furnace with elements necessary to form the amorphous alloy, rapidly quenching the alloy, forming a core from the alloy; and heating the core in the presence of a magnetic field to form the nanocomposite alloy.

Abstract: Magnetic component assemblies including coil coupling arrangements, that are advantageously utilized in providing surface mount magnetic components such as inductors and transformers.

Abstract: A reactor 1A includes a single coil 2 formed by spirally winding a wire 2w and a magnetic core 3 that is disposed inside and outside the coil 2 and forms a closed magnetic circuit. The magnetic core 3 includes an inner core portion 31 disposed inside the coil 2 and an outer core portion 32 disposed so as to cover the outer periphery of the coil 2. The outer core portion 32 is formed of a composite material containing a magnetic powder and a resin. In a section of this composite material, the maximum bubble diameter is 300 ?m or less. In the reactor 1A, the outer core portion 32 has a maximum bubble diameter of 300 ?m or less and, as a result, the loss is low and magnetic characteristics are less likely to be decreased.

Abstract: The present invention concerns a composite iron-based powder mix suitable for soft magnetic applications such as inductor cores. The present invention also concerns a method for producing a soft magnetic component and the component produced by the method.

Abstract: Ferromagnetic cores made from amorphous glasses and methods of forming ferromagnetic cores from metallic glasses are provided. The method forms a magnetic core from a section of a series of concentrically nested ferromagnetic tubes formed of an amorphous metallic material having a Curie-point temperature above room temperature and demonstrating soft ferromagnetic properties, thereby simplifying the manufacturing process and improving the electrical and mechanical performance of the core itself.

Abstract: A magnetic core of superparamagnetic core shell nanoparticles having a particle size of less than 200 nm; wherein the core is an iron cobalt ternary alloy and the shell is a silicon oxide is provided. The magnetic core is a monolithic structure of superparamagnetic core grains of an iron cobalt ternary alloy directly bonded by the silicon dioxide shells. A method to prepare the magnetic core which allows maintenance of the superparamagnetic state of the nanoparticles is also provided. The magnetic core has little core loss due to hysteresis or eddy current flow.

Abstract: Disclosed herein are a ferrite powder not including pores in a surface thereof, a method for preparing the same, and a common mode noise filter including the same as a material for a magnetic layer. The spherical ferrite powder in which the pores in the surface thereof are removed as a magnetic layer of the common mode noise filter has high density, such that dispersibility is improved, thereby making it possible to improve adhesive strength with a polymer binder to be mixed. In addition, the adhesive strength between the polymer binder and the ferrite powder is improved, such that at the time of manufacturing or mounting of a chip, a defect such as a crack generated by a thermal impact due to a lack of adhesive strength between the ferrite powder and the polymer binder may be suppressed, thereby securing the reliability with respect to the thermal impact.

Abstract: As an embodiment, a pair of first conductive films 12, 13 are formed from the side face to the bottom face of the sheet part 11a of a magnetic core 11, and one end 14b of the conductive wire of the coil 14 and the other end 14c of the conductive wire are joined to the side faces 12a, 13a of the first conductive films 12, 13, respectively. Also, as an embodiment, the joined parts 14b1, 14c1 are sandwiched by the side faces 12a, 13a of the first conductive films 12, 13 and the part 15a of the magnetic sheath 15 covering the side face of the sheet part 11a of the magnetic core 11, wherein the parts of the magnetic sheath 15 covering the joined parts 14b1, 14c1 are sandwiched by the side faces 12a, 13a of the first conductive films 12, 13 and the side faces 16a, 17a of second conductive films 16, 17 as well as the side faces 18a, 19a of third conductive films 18, 19.

Abstract: An electronic component and manufacturing method for preparing an electronic component includes providing a first insulator layer having a first nickel content rate. A coil conductor and a second insulator layer having a first bismuth content rate and a second nickel content rate higher than the first nickel content rate are provided on the first insulator layer. The first insulator layer, the coil conductor, and the second insulator layer constitute a first unit layer. The first unit layer and an exterior insulator layer are laminated to obtain a laminate. After a step of firing the laminate, a nickel content rate in a first portion of the first insulator layer, the first portion being sandwiched between the coil conductors from both sides facing in a lamination direction, is lower than a nickel content rate in a second portion of the first insulator layer other than the first portion.

Abstract: Provided are a small wire-wound inductor having desired inductor characteristics, while allowing for high-density mounting and low-height mounting on circuit boards at the same time, as well as a method for manufacturing such wire-wound inductor which has a drum-shaped core member constituted by an assembly of soft magnetic alloy grains containing iron (Fe), silicon (Si) and 2 to 15 percent by weight of chromium (Cr), a coil conductive wire wound around the core member, a pair of terminal electrodes connected to the terminals of the coil conductive wire, and an outer sheath member covering the wound coil conductive wire and constituted by a magnetic powder-containing resin having a specified magnetic permeation ratio.

Abstract: The main purpose of this invention is to improve high forming pressure of existing Fe—Si—Al insulating magnetic powder which is not suitable for forming, combine heterogeneous insulating magnetic powder, produce hollow cup-like cover and Fe—Si—Al rod core for full magnetic path component assembling, and change the shape structure of rod core and cover design, so there will be advantages including easy to winding, assemble and cooling.

Abstract: Disclosed herein is a common mode noise filter independently including ferrite powder having pores formed in a surface thereof or including at least two kinds of ferrite powder having different particle sizes as a magnetic layer. According to the present invention, the adhesive strength between the polymer binder and the ferrite powder that are included in the magnetic layer is improved, such that at the time of manufacturing or mounting of a chip, a defect such as a crack generated by a thermal impact due to a lack of adhesive strength between the ferrite powder and the polymer binder may be suppressed, thereby securing the reliability with respect to the thermal impact.

Abstract: A power acquisition device fixed to an illuminating device having a fluorescent tube and a reflective plate so as to acquire power from a magnetic field generated by an alternating current flowing through the fluorescent tube by electromagnetic induction. The power acquisition device is fixed so as to surround the fluorescent tube and at least one of the thickness in the direction perpendicular to the surface of the fluorescent tube and the length in the direction parallel to the length direction of the fluorescent tube is non-uniformly.

Abstract: A magnetic core of superparamagnetic core shell nanoparticles having a particle size of less than 50 nm; wherein the core is an iron oxide and the shell is a silicon oxide is provided. The magnetic core is a monolithic structure of superparamagnetic core grains of iron oxide directly bonded by the silicon dioxide shells. A method to prepare the magnetic core which allows maintenance of the superparamagnetic state of the nanoparticles is also provided. The magnetic core has little core loss due to hysteresis or eddy current flow.

Abstract: Provided is a reactor that enables high inductance to be generated with stability in a wide current range, while minimizing noise, processing cost, and eddy-current loss. The reactor (D1) has the ratio (t/W) of the width (W) to the thickness (t) of a conductive member that composes an air-core coil configured to be 1 or less, and preferably, 1/10 or less. Furthermore, the reactor also has the absolute value of a value ((L1?L2)/L3) that has had: the difference (L1?L2) between; the space interval (L1) between an inner wall face of a first core member (3) and an inner wall face of a second core member (4), at the innermost circumference position of the air-core coil (1); and the space (L2) between the inner wall face of the first core member (3) and the inner wall face of the second core member (4), at the outermost circumference position of the air-core coil (1); divided by an average value (L3); configured to be 1/50 or less.

Abstract: A laminated inductor having an internal conductive wire forming region, as well as a top cover region and bottom cover region formed in a manner sandwiching the internal conductive wire forming region between top and bottom; wherein the internal conductive wire forming region has a magnetic part formed with soft magnetic alloy grains, as well as helical internal conductive wires embedded in the magnetic part and constituted by a conductor; and at least one of the top cover region and bottom cover region (or preferably both) is/are formed with soft magnetic alloy grains whose constituent elements are of the same types as those of, and whose average grain size is greater than that of, the soft magnetic alloy grains constituting the magnetic part in the internal conductive wire forming region.

Abstract: A choke includes a single-piece core made of a same material, the single-piece core having a first board, a second board, and a pillar located between the first and second boards, a winding space located among the first board, the second board and the pillar, wherein the pillar has a non-circular and non-rectangular cross section having a first axis and a second axis substantially perpendicularly intersecting with each other at a center of the cross section of the pillar, and wherein a circumference of the cross section of the pillar includes two arc edges, four first substantially straight edges substantially parallel to the first axis, and two second substantially straight edges substantially parallel to the second axis, each of the first substantially straight edges being a joint of and in direct contact with one of the arc edges and one of the second substantially straight edges.

Abstract: In one embodiment, a stimulation lead comprises: a lead body of insulative material surrounding a plurality of conductors; a plurality of electrodes; and a plurality of terminals, the plurality of terminals electrically coupled to the plurality of electrodes through the plurality of conductors; wherein each conductor of the plurality of conductors is helically wound about an axis within the lead body in at least an outer portion and an inner portion relative to the axis, the outer portion comprises a first winding pitch and the inner portion comprises a second winding pitch, the second winding pitch is less than the first winding pitch, the inner portion of each respective conductor being disposed interior to the outer portions of other conductors of the plurality of conductors; wherein an impedance of each conductor of the plurality of conductors substantially reduces MRI-induced current when the stimulation lead is present in an MRI system.

Abstract: A low-loss compact and a method for producing the compact are provided. A method for producing a compact by using coated soft magnetic powder that includes coated soft magnetic particles constituted by soft magnetic particles and insulating coatings coating outer peripheries of the soft magnetic particles includes a raw material preparation step and an irradiation step. In the raw material preparation step, a raw compact is prepared by press-forming coated soft magnetic powder. In the irradiation step, part of a surface of the raw compact is irradiated with a laser. Irradiating a part of a surface of a raw compact with laser increases the number of disrupted portions of conductive portions where constituent materials of the soft magnetic particles at the surface of the raw compact have become conductive to each other, and the loss of the compact can be decreased.

Abstract: Provided is a laminated inductor having a magnetic body, a conductor part covered in a manner directly contacting the magnetic body, and external terminals provided on the outside of the magnetic body and conducting to the conductor part; wherein the magnetic body is a laminate constituted by layers containing soft magnetic alloy grains, and the soft magnetic alloy grain contacting the conductor part is flattened on the conductor part side.

Abstract: A tape wound inductor core device, inductors including same and methods of manufacture. Tape wound material may be cut and/or shaped into “pucks” that have an exterior surface made up of or defined substantially by the edge surfaces of the layers of the constituent conductive material, with all or most of the broad surfaces disposed inwardly, thereby reducing eddy currents and associated losses. Various puck configurations, inductor arrangements and fabrication techniques are disclosed.

Abstract: A magnetic device including a first magnetic core is disclosed. The first magnetic core includes a base having a first edge; a first contacting structure disposed on the base; and a second contacting structure disposed on the base, wherein a distance between an inner surface of the first contacting structure and the first edge is larger than a distance between an inner surface of the second contacting structure and the first edge.

Abstract: A laminated inductor having a laminate structure constituted by magnetic layers and internal conductive wire-forming layers, wherein the magnetic layer is formed by soft magnetic alloy grains, the internal conductive wire-forming layer has an internal conductive wire and a reverse pattern portion around it, and the reverse pattern portion is formed by soft magnetic alloy grains whose constituent elements are of the same types as those of, and whose average grain size is greater than that of, the soft magnetic alloy grains constituting the magnetic layer.

Abstract: Provided is a reactor having a small size. A reactor 1? includes a coil 2? and a magnetic core 3? in which the coil 2? is disposed. The magnetic core 3? includes an internal core portion 3i that is inserted through the coil 2? and a couple core portion 3o that covers the outer periphery of the coil 2?, and these core portions form a closed magnetic path. The reactor 1? satisfies 1<(B1/B2) and 0.17×(B1/B2)+0.42?(S1×B1)/(S2×B2)?0.50×(B1/B2)+0.62, where S1 is the cross-sectional area of the internal core portion, B1 is the saturation magnetic flux density of the internal core portion, S2 is the cross-sectional area of the couple core portion, B2 is the saturation magnetic flux density of the couple core portion, (B1/B2) is the saturation magnetic flux density ratio between the core portions, and (S1×B1)/(S2×B2) is the magnetic flux ratio between the core portions.

Abstract: An electronic device including a magnetic body and a wire is provided. The magnetic body has a first magnetic powder and a second magnetic powder mixed with the first magnetic powder. The Vicker's Hardness of the first magnetic powder is greater than that of the second magnetic powder and the mean particle diameter of the first magnetic powder is greater than that of the second magnetic powder.

Abstract: Magnet core for low-frequency applications and method for producing a magnet core for low-frequency applications A magnet core for low-frequency applications made of a spiral-wound, soft-magnetic, nanocrystalline strip is provided, the strip essentially having the alloy composition FeRestCoaCubNbcSidBeCf, wherein a, b, c, d, e and f are stated in atomic percent and 0?a?1; 0.7?b?1.4; 2.5?c?3.5; 14.5?d?16.5; 5.5?e?8 and 0?f?1, and cobalt may wholly or partially be replaced by nickel, the magnet core having a saturation magnetostriction ?s of ?s<2 ppm, a starting permeability ?1 of ?1>100 000 and a maximum permeability ?max of ?max>400 000, and a sealing metal oxide coating being provided on the surfaces of the strip.

Abstract: A magnetostrictive element is provided comprising at least one device for generating a magnetic field, and at least one shaped part made of porous polymer containing ferromagnetic particles. The magnetostrictive element is characterized by having a distinct magnetostrictive effect.

Abstract: In a reactor core, a gap section between a plurality of core material portions is fixed by adhesion through a spacer, and a resin is arranged vertical to the adhering surface between the core material and the spacer, for sandwiching at least a part of the core material. The resin material preferable a molded material.

Abstract: Disclosed is an iron-based soft magnetic powder obtained by preparing an iron-oxide-based soft magnetic powder through water atomization, and thermally reducing the iron-oxide-based soft magnetic powder. The iron-based soft magnetic powder has an average particle size of 100 ?m or more and has an interface density of more than 0 ?m?1 and less than or equal to 2.6×10?2 ?m?1, where the interface density is determined from a cross-sectional area (?m2) and a cross-sectional circumference (?m) of the iron-based soft magnetic powder. The iron-based soft magnetic powder obtained by preparing an iron-oxide-based soft magnetic powder through water atomization and thermally reducing the iron-oxide-based soft magnetic powder, when used for the production of a dust core, can give a dust core having a low coercive force. Also disclosed is a duct core having a low coercive force and exhibiting superior magnetic properties.

Abstract: A composite magnetic core assembly includes an inner magnetic core and an outer magnetic core. The inner magnetic core is made of a high saturation flux density and low permeability material. The outer magnetic core is made of a low saturation flux density and high permeability material. The outer magnetic core includes a ring-shaped wall and a receptacle. The inner magnetic core is accommodated within the receptacle.

Abstract: A protective coating system for application to exposed surfaces of a transformer core prevents corrosion of the core. The protective coating is suitable for use in industrial and marine environments where many factors impact the life of the transformer core. The protective coating comprises at least three coating layers. The first coating layer is an inorganic zinc silicate primer. The second coating layer is a polysiloxane. The third coating layer is a room temperature or high temperature vulcanizing silicone rubber. A silicone rubber sealant may be further applied to outer edge surfaces of the core.

Abstract: A transformer structure having double-axis iron core is disclosed. The iron core structure mainly includes an iron core main body that has a base. The base has a parallel salient side convex part furnished respectively at the two opposite side edge thereof, and has a chamfered part furnished respectively at the two end parts corresponding to the side convex part thereof. It utilizes two iron core main bodies to be oppositely combined. In association with different shapes of coil, it is capable of forming various transformer structures and possesses a variety of combination, and is capable of adapting to various requirements of the product.

Abstract: A reactor device is provided with a yoke section incorporating an elliptical wire-wound iron core and an iron-core leg section having wire-wound iron cores stacked one on another. The reactor device may have significantly deteriorated magnetic properties due to an abnormal current caused by a magnetic flux developed in the leg section. The short circuit of the abnormal current is cut by providing a cut portion from the center of the end surface of a wire-wound iron core in the leg section to the outer shape thereof and then insulating the cut portion. Use is made of a fixture jig to maintain the shape of the iron core even after the iron core has been cut, and at a final stage, use is made of a band or tape for maintaining the shape. The band used for maintaining the shape is adapted to prevent a magnetic flux developed in the iron core from making one turn.

Abstract: A reactor has a cylindrical molded coil assembly formed by covering a coil with a resin, wherein the coil assembly is sealed by an iron powder mixed resin to which iron powder has been admixed. The reactor has an axial core shaft, and single or multiple ring-shaped core members. The ring-shaped core members are disposed outside the outer surface of the core shaft such that the core shaft is inserted inside the inner surface of said ring-shaped core members, and the coil assembly is disposed outside the outer surface of the ring-shaped core member such that the ring-shaped core members are inserted inside the inner surface of said coil assembly. A protrusion protruding inwards from the inner surface of the coil assembly contacts the axial end surface of a ring-shaped core member.