A rotary transformer for an electrical machine includes a rotary printed circuit board and a stator printed circuit board. The rotary printed circuit board is operatively connected to the stator printed circuit board for relative rotation with respect to the stator printed circuit board. A conductor is fixed to the one of the printed circuit boards and includes a spiral coil for transferring electrical energy between the rotary printed circuit board and stator printed circuit board.

In a single phase transformer core and transformer, thin-strip metal is wound into multiple rings of different widths and arranged to define a ring-like structure having a stepped, substantially circular cross-section without any cuts or gaps in the magnetic path, or the core is wound from a tapered strip that is configured to define a substantially circular cross-section when wound, while in a three phase transformer core and transformer two inner frames, each made of one or more wound rings are arranged side-by-side and an outer frame of one or more rings is wound around the two inner frames, the core being covered with epoxy prior to winding coils on it.

An electronic component including a body portion and an electrode disposed on the body portion is provided. The electrode includes a first metal layer, a second metal layer, and a third metal layer. The first metal layer contains silver (Ag) as a main component and includes first dispersion portions containing glass as a main component and second dispersion portions containing nickel as a main component. The second metal layer is disposed on the first metal layer and contains nickel (Ni) as a main component. The third metal layer is disposed on the second metal layer and contains tin (Sn) as a main component. An area of the first dispersion portions is larger than an area of the second dispersion portions in a sectional view of the electrode.

An electronic component including a body portion and an electrode disposed on the body portion is provided. The electrode includes a first metal layer, a second metal layer, and a third metal layer. The first metal layer contains silver (Ag) as a main component and includes first dispersion portions containing glass as a main component and second dispersion portions containing nickel as a main component. The second metal layer is disposed on the first metal layer and contains nickel (Ni) as a main component. The third metal layer is disposed on the second metal layer and contains tin (Sn) as a main component. An area of the first dispersion portions is larger than an area of the second dispersion portions in a sectional view of the electrode.

A magnetic element includes at least one primary winding, at least one secondary winding, a magnetic core, and an auxiliary winding. A winding segment or an entire of the primary winding or a winding segment or an entire of the secondary winding is defined as a parallel-connected winding set. The magnetic core includes a plurality of winding legs, two lateral legs, and two connection parts. The at least one primary winding and the at least one secondary winding are wound around each winding leg. The directions of magnetic fluxes through every two adjacent winding legs are opposite. The auxiliary winding is wound on one of two lateral legs, and electrically connected with the parallel-connected winding set. A direction of a magnetic flux generated by the auxiliary winding is opposite to a direction of the magnetic flux through the adjacent winding leg.

A magnetic element includes at least one primary winding, at least one secondary winding, a magnetic core, and an auxiliary winding. A winding segment or an entire of the primary winding or a winding segment or an entire of the secondary winding is defined as a parallel-connected winding set. The magnetic core includes a plurality of winding legs, two lateral legs, and two connection parts. The at least one primary winding and the at least one secondary winding are wound around each winding leg. The directions of magnetic fluxes through every two adjacent winding legs are opposite. The auxiliary winding is wound on one of two lateral legs, and electrically connected with the parallel-connected winding set. A direction of a magnetic flux generated by the auxiliary winding is opposite to a direction of the magnetic flux through the adjacent winding leg.

A coil part includes: a bobbin including a flange part constituting a winding frame part around which a lead wire is to be wound; a core attached to the bobbin; and a core pressing part which is provided integrally with the flange part, includes a pressing plate part facing the flange part to form a first gap, and presses the core between the flange part and the pressing plate part by inserting at least a part of the core into the first gap.

A coil part includes: a bobbin including a flange part constituting a winding frame part around which a lead wire is to be wound; a core attached to the bobbin; and a core pressing part which is provided integrally with the flange part, includes a pressing plate part facing the flange part to form a first gap, and presses the core between the flange part and the pressing plate part by inserting at least a part of the core into the first gap.

A microelectronic device includes a magnetic component having a first magnetic core segment and a second magnetic core segment, with a winding lamina between them. The first magnetic core segment includes a winding support portion with ferromagnetic material. The winding lamina is attached to the winding support portion. The first magnetic core segment also includes an extension portion with ferromagnetic material extending from the winding support portion. The winding lamina has winding loops of electrically conductive material that surround ferromagnetic material. A filler material is formed between the winding lamina and the first magnetic core segment, contacting both the winding lamina and the first magnetic core segment. The second magnetic core segment is attached to the extension portion of the first magnetic core segment. The second magnetic core segment includes ferromagnetic material. The winding loops are electrically coupled to external leads through electrical connections.

A microelectronic device includes a magnetic component having a first magnetic core segment and a second magnetic core segment, with a winding lamina between them. The first magnetic core segment includes a winding support portion with ferromagnetic material. The winding lamina is attached to the winding support portion. The first magnetic core segment also includes an extension portion with ferromagnetic material extending from the winding support portion. The winding lamina has winding loops of electrically conductive material that surround ferromagnetic material. A filler material is formed between the winding lamina and the first magnetic core segment, contacting both the winding lamina and the first magnetic core segment. The second magnetic core segment is attached to the extension portion of the first magnetic core segment. The second magnetic core segment includes ferromagnetic material. The winding loops are electrically coupled to external leads through electrical connections.