Patent attributes
Since there exists a draw-out portion of a triple insulated wire in a winding structure of a transformer in which the triple insulated wire is used as a secondary winding, the thickness of the transformer is increased by an amount corresponding to the wire diameter of the draw-out portion. Further, when reduction of the thickness of the transformer is prioritized, the secondary winding can be provided only on one side, making it impossible to achieve the sandwich structure. Thus, the coupling between the primary and secondary windings has been sacrificed. An inductance part provided with a magnetic core, two or more sheet coils, and a winding includes: a bobbin constituted by at least two or more sheet coils; and a winding formed by winding a triple insulated wire between the two or more sheet coils constituting the bobbin. A triple insulated wire draw-out portion on the center side of the winding is drawn out to one outer surface side of the bobbin.