A method for manufacturing an electromagnetic coil with an intentionally engineered heat flow path is provided. The method includes defining at least one preferential heat flow path for heat to flow for the electromagnetic coil. A coil cartridge in which to encase the electromagnetic coil is designed by selecting dimensions of different portions of the insulating coil cartridge that will result in the at least one preferential heat flow path. The electromagnetic coil is then encased in coil cartridge material to produce an encased electromagnetic coil.

An inductor device includes a first and a second inductor. First inductor includes plural first wires and a first connection member. Second inductor includes plural second wires and a second connection member. Part of first wires are winded/located at a first area, and part of first wires are winded/located at a second area. First and second areas are located on two opposite sides of inductor device. First connection member connects first wire located at first area and located at second area. Part of second wires are winded/located at first area, and part of second wires are winded/located at second area. One terminal of second connection member connects a terminal of second wire at an inner side of inductor device, and another terminal of second connection member is disposed outside inductor device. First and second inductors are symmetrical with respect to a center line of inductor device.

An inductor device includes a first and a second inductor. First inductor includes plural first wires and a first connection member. Second inductor includes plural second wires and a second connection member. Part of first wires are winded/located at a first area, and part of first wires are winded/located at a second area. First and second areas are located on two opposite sides of inductor device. First connection member connects first wire located at first area and located at second area. Part of second wires are winded/located at first area, and part of second wires are winded/located at second area. One terminal of second connection member connects a terminal of second wire at an inner side of inductor device, and another terminal of second connection member is disposed outside inductor device. First and second inductors are symmetrical with respect to a center line of inductor device.

A coil electronic component includes a body having first to fourth surfaces, an insulating substrate disposed in the body, coil portions disposed on opposing surfaces of the insulating substrate, respectively, a first lead-out portion connected to one of the coil portions and exposed from the first and third surfaces, a second lead-out portion connected to another of the coil portions and exposed from the second and third surfaces, and first and second external electrodes covering the first and second lead-out portions, respectively. The insulating substrate includes a support portion supporting the coil portions, a first end portion extending from the support portion and including end surfaces respectively exposed from the first and third surfaces and spaced apart from each other, and a second end portion extending from the support portion and including end surfaces exposed from the second and third surfaces and spaced apart from each other.

A coil electronic component includes a body having first to fourth surfaces, an insulating substrate disposed in the body, coil portions disposed on opposing surfaces of the insulating substrate, respectively, a first lead-out portion connected to one of the coil portions and exposed from the first and third surfaces, a second lead-out portion connected to another of the coil portions and exposed from the second and third surfaces, and first and second external electrodes covering the first and second lead-out portions, respectively. The insulating substrate includes a support portion supporting the coil portions, a first end portion extending from the support portion and including end surfaces respectively exposed from the first and third surfaces and spaced apart from each other, and a second end portion extending from the support portion and including end surfaces exposed from the second and third surfaces and spaced apart from each other.

A wire wound-type coil component with an integrated structure does not have a bonding portion where there is concern about reliability with respect to a spiral conductive wire, a terminal electrode, and an annular core. A coil component includes a core with an integrated structure, at least part of which is a winding core portion, which has an annular shape having a through-hole, and which is made of a non-conductive material; and a coil conductor with an integrated structure, which has a spiral conductive wire arranged to spirally extend around the winding core portion and first and second terminal electrodes formed at both end portions of the spiral conductive wire, respectively. The coil component is manufactured through three-dimensionally shaping the core, the coil conductor, and a shape holding member for holding a shape of a wall surface of the core defining the through-hole, by using a 3D printer.

A wire wound-type coil component with an integrated structure does not have a bonding portion where there is concern about reliability with respect to a spiral conductive wire, a terminal electrode, and an annular core. A coil component includes a core with an integrated structure, at least part of which is a winding core portion, which has an annular shape having a through-hole, and which is made of a non-conductive material; and a coil conductor with an integrated structure, which has a spiral conductive wire arranged to spirally extend around the winding core portion and first and second terminal electrodes formed at both end portions of the spiral conductive wire, respectively. The coil component is manufactured through three-dimensionally shaping the core, the coil conductor, and a shape holding member for holding a shape of a wall surface of the core defining the through-hole, by using a 3D printer.

A transformer that can easily cope with various input voltage specifications and that, has improved productivity is obtained. A transformer includes: a core portion for forming a magnetic circuit; and a primary-side winding and a secondary-side winding wound at the core portion. One or both of the primary-side winding and the secondary-side winding are divided into a plurality of division windings, and each of the plurality of the division windings of the at least one divided winding has a wound part wound at the core portion, and two extending members extending from both ends of the wound part. The extending members of the plurality of the division windings of the at least one divided winding are mutually connected, and a number of turns in the transformer of the at least one divided winding is set.

A transformer that can easily cope with various input voltage specifications and that, has improved productivity is obtained. A transformer includes: a core portion for forming a magnetic circuit; and a primary-side winding and a secondary-side winding wound at the core portion. One or both of the primary-side winding and the secondary-side winding are divided into a plurality of division windings, and each of the plurality of the division windings of the at least one divided winding has a wound part wound at the core portion, and two extending members extending from both ends of the wound part. The extending members of the plurality of the division windings of the at least one divided winding are mutually connected, and a number of turns in the transformer of the at least one divided winding is set.

A method for manufacturing a coil component includes: a first winding step to wind a first conductive wire around a winding core in a single layer from a first flange part toward a second flange part; and a second winding step to wind a second conductive wire around the winding core on the first conductive wire by the same number of turns and in the same direction as in the first winding step in a single layer in a manner that center B of the cross-section of the second conductive wire closest to the first flange part is positioned closer to the first flange part than is center A of the cross-section of the first conductive wire closest to the first flange part, and that the distance in the axial direction, between centers A and B is smaller than the radius of the wire.