A coil component includes an insulator part and a coil part. The insulator part is constituted by an electrical insulation material, and is no more than 600 μm long and no more than 600 μm high. The coil part is wound around one axis and placed inside the insulator part. The coil part has an opening part constituted by straight line parts and curved line parts and whose shape as viewed from the one axis direction is an approximate quadrangle, wherein the line length of the curved line parts along the inner periphery of the opening part is 20% or more but no more than 40% of the line length of the inner periphery of the opening part. The coil component can satisfy both a size reduction need and the properties need.

A coil component includes an insulator part and a coil part. The insulator part is constituted by an electrical insulation material, and is no more than 600 μm long and no more than 600 μm high. The coil part is wound around one axis and placed inside the insulator part. The coil part has an opening part constituted by straight line parts and curved line parts and whose shape as viewed from the one axis direction is an approximate quadrangle, wherein the line length of the curved line parts along the inner periphery of the opening part is 20% or more but no more than 40% of the line length of the inner periphery of the opening part. The coil component can satisfy both a size reduction need and the properties need.

A coil assembly including a plurality of substantially planar plates interconnected to define a plurality of electrically conductive windings for surrounding a magnetic core. In one example the invention is used for a magnetic core assembly, including a magnetic core and at least two coil assemblies, the coil assemblies each including a plurality of substantially planar plates interconnected to define a plurality of electrically conductive windings for surrounding the magnetic core.

A coil assembly including a plurality of substantially planar plates interconnected to define a plurality of electrically conductive windings for surrounding a magnetic core. In one example the invention is used for a magnetic core assembly, including a magnetic core and at least two coil assemblies, the coil assemblies each including a plurality of substantially planar plates interconnected to define a plurality of electrically conductive windings for surrounding the magnetic core.

A method is provided for the production of a wound nanocrystalline magnetic core in which a nanocrystalline metal strip made of (Fe.sub.1-aM.sub.a).sub.100-x-y-z-α-βCu.sub.xSi.sub.yB.sub.zM′.sub.αX.sub.β is pre-wound to form a first coil. An insulating foil is provided that is coated with an adhesive on at least one side. An adhesive is applied to the nanocrystalline metal strip to laminate the insulating foil onto the metal strip and thereby to stabilise the metal strip as it is wound off the coil. The laminated nanocrystalline metal strip and the insulating foil are bifilar wound to form a bifilar, layer-insulated coil.

A coating layer is formed on a coil made of an insulated conductive wire comprising a metal wire and an insulating layer encapsulating the metal layer, wherein the coating layer encapsulates at least one portion of the insulating layer of the insulated conductive wire so that a terminal part of the metal wire exposed from the insulating layer can be positioned firmly while going through an automatic soldering process for electrically connecting with an external circuit.

A coating layer is formed on a coil made of an insulated conductive wire comprising a metal wire and an insulating layer encapsulating the metal layer, wherein the coating layer encapsulates at least one portion of the insulating layer of the insulated conductive wire so that a terminal part of the metal wire exposed from the insulating layer can be positioned firmly while going through an automatic soldering process for electrically connecting with an external circuit.

In some examples, an isolation transformer can include a first wire having a first insulation thickness and a second wire having a second insulation thickness that is different than the first insulation thickness. The isolation transformer can further include a plurality of magnetic cores of magnetic material that can be configured to surround portions of each of the first and second wires along respective circumferences of the first and second wires to provide the isolation transformer.

In some examples, an isolation transformer can include a first wire having a first insulation thickness and a second wire having a second insulation thickness that is different than the first insulation thickness. The isolation transformer can further include a plurality of magnetic cores of magnetic material that can be configured to surround portions of each of the first and second wires along respective circumferences of the first and second wires to provide the isolation transformer.

A coil component is capable of suppressing occurrence of peeling at an interface between a coil conductor and resin in a magnetic portion due to heating during mounting. The coil component includes an element body that includes a coil conductor formed by winding a conductive wire coated with an insulating film, and a magnetic portion that contains metal magnetic particles and resin, and external electrodes that are electrically connected to exposed surfaces of extended portions of the coil conductor exposed on a surface of the element body, and are arranged on the surface of the element body. The metal magnetic particles are arranged in recesses formed in a surface of the conductive wire in the extended portions of the coil conductor.