A method to form a plurality of inductors in a single process by stacking multiple magnetic sheets, wherein each sheet is made to form a particular part in quantities, which can be a base part, a pillar part, a hollow part, or a cover part, for forming a magnetic body of an inductor.

A method and an apparatus for almost scrap-less manufacturing of magnetic cores for electrical power transformers or reactors. The method cutting a cut-out from the middle of a long side of a rectangular yoke plate made of electrical steel such that a symmetric gap is formed in the yoke plate, forming building elements grain oriented electrical steel either from the cut-out or from a rectangular limb plate, repositioning the building elements such that at least some of the building elements get a new orientation and/or position in relation to the yoke plate or the limb plate, and building a magnetic core by assembling at least yoke plates and repositioned building elements such that the repositioned building elements fit into the symmetric gaps. Magnetic cores for electrical power transformers or reactors are also provided, where the core losses and noise levels are reduced compared to prior art technology.

An inductor has one or more wires and a multipart magnetic core. The multipart magnetic core has magnetic core parts that are adjacent and magnetically coupled. The inductor provides an inductance of at least 40 nH for currents greater than 1 A and less than 60 A, and at least 20 nH for currents of at least 60 A.

An iron core including a laminate of a plurality of fixed electromagnetic steel sheets, a laminate of alloy thin strips which is sandwiched between the laminate of the electromagnetic steel sheets, a fastening mechanism which penetrates the laminates of electromagnetic steel sheets and alloy thin strips, and a fixing base. The laminate of alloy thin strips reduces compressive and torsional forces acting on the laminate of alloy thin strips by using the iron core having a structure in which upper and lower portions of a laminate of alloy thin strips having nanocrystal grains are sandwiched together with laminates of amorphous alloy thin strips. Furthermore, a motor including a rotor and the above-described iron core is used.

To provide a magnetic element capable of reducing working man hour, the number of components, and an amount of a copper wire. A magnetic element 1 is provided with a coil assembly 4 including a core 2 formed by a compression molded magnetic body and a coil 3 wound on an outer periphery of the core 2, and an outer peripheral core 5 that surrounds an outer periphery of the coil assembly 4. The outer peripheral core 5 is formed by an injection molded magnetic body and includes an opening 5a into which the coil can be inserted, and a pair of grooves 5b into which both end portions in an axial direction of the core 2, the groove 5b being provided as a fixing unit for fixing the coil assembly 4 in the outer peripheral core and formed on an inner peripheral surface of the outer peripheral core.

A wireless device is provided and includes a substrate, a first coil and a second coil. The first coil is configured to be wound around a first axis, and the first coil is disposed on the substrate and is configured to operate in a wireless charging mode. The second coil is disposed on the substrate and configured to operate in a wireless communication mode. The wires of the second coil partially overlap the wires of the first coil.

A compact is provided. When the compact is used for a magnetic core, a magnetic path cross section has a cross-sectional perimeter of more than 20 mm, and at least part of a surface of the compact is covered with an iron-based oxide film having an average thickness of 0.5 μm or more and 10.0 μm or less. Letting the proportion of the surface area of the compact to the volume of the compact be surface area/volume, the content of Fe.sub.3O.sub.4 present in the iron-based oxide film with respect to 100% by volume of the compact satisfies any one of (1) to (3): (1) less than 0.085% by volume when the (surface area/volume) is 0.40 mm.sup.−1 or less, (2) 0.12% or less by volume when the (surface area/volume) is more than 0.40 mm.sup.−1 and 0.60 mm.sup.−1 or less, and (3) 0.15% or less by volume when the (surface area/volume) is more than 0.60 mm.sup.−1.

In a common mode choke coil having a magnetic core, a decrease in peak value of a common mode impedance in a vicinity of its resonance frequency is suppressed. A common mode choke coil includes a non-magnetic layer, a first magnetic layer formed on a top surface of the non-magnetic layer, a second magnetic layer formed on a bottom surface of the non-magnetic layer, a magnetic core provided between the first magnetic layer and the second magnetic layer so that its axis extends in a top-bottom direction, a first coil conductor embedded in the non-magnetic layer and wound around the magnetic core, a second coil conductor embedded in the non-magnetic layer and wound around the magnetic core, and a first magnetic gap provided between a top surface of the magnetic core and a bottom surface of the first magnetic layer. The magnetic core is made of a ferrite material.

An inductor includes a magnetic core composed of a magnetic material having variable permeability characteristics based on at least one of design parameters or operational parameters of the inductor that includes one or more air gaps. A coil is wound through the one or more air gaps and is configured to be excited by an electric current.

A reactor including: a coil having a winding portion; a magnetic core that is disposed extending inside and outside the winding portion, and is configured to form a closed magnetic circuit; and a resin mold that includes an inner resin disposed between the winding portion and the magnetic core, and does not cover an outer peripheral face of the winding portion.