An electromagnet comprises a plurality of nested freestanding electrically insulating former layers, and electrically conductive wire wrapped around the outsides of the freestanding electrically insulating former layers to define a multilayer electrical coil in which adjacent layers of the multilayer electrical coil are spaced apart by intervening freestanding electrically insulating former layers. Electrically energizing the multilayer electrical coil generates a magnetic field inside the multilayer electrical coil. In some embodiments the electrically conductive wire is bare wire not having electrical insulation. In some embodiments the former layers comprise a ceramic material. In some such embodiments the electromagnet further comprises a ferromagnetic core disposed inside the multilayer electrical coil. An electric motor employing such an electromagnet as a stator pole is also disclosed. Control rod drive mechanism (CRDM) and coolant pump embodiments are also disclosed employing such a motor, for use in a nuclear reactor.

In an ignition coil for an internal combustion engine, a coil case includes a housing section and a high-voltage tower section. The housing section houses a primary coil, a secondary coil, a center core, and an outer peripheral core, and is arranged outside a plug hole in a cylinder of an internal combustion engine in which an ignition plug is arranged. The high-voltage tower section protrudes from the housing section, and is disposed within the plug hole. A pole joint is disposed within the plug hole, and is mounted to the high-voltage tower section via a seal rubber. The pole joint is provided with a rib that protrudes to an outer periphery and faces an inner peripheral surface of the plug hole. The inner peripheral side of the rib faces the high-voltage tower section via the seal rubber.

An electromagnet comprises a plurality of nested freestanding electrically insulating former layers, and electrically conductive wire wrapped around the outsides of the freestanding electrically insulating former layers to define a multilayer electrical coil in which adjacent layers of the multilayer electrical coil are spaced apart by intervening freestanding electrically insulating former layers. Electrically energizing the multilayer electrical coil generates a magnetic field inside the multilayer electrical coil. In some embodiments the electrically conductive wire is bare wire not having electrical insulation. In some embodiments the former layers comprise a ceramic material. In some such embodiments the electromagnet further comprises a ferromagnetic core disposed inside the multilayer electrical coil. An electric motor employing such an electromagnet as a stator pole is also disclosed. Control rod drive mechanism (CRDM) and coolant pump embodiments are also disclosed employing such a motor, for use in a nuclear reactor.

High-voltage, high-frequency and high-power transformer having a core (1) on which a primary winding (2) is disposed on which a secondary winding (4) is disposed in an insulated manner, whereupon the entire assembly is housed and mounted in an insulator (3), wherein the insulator (3) is made up of two parts or halves (6) and (7) symmetrical with respect to a transverse vertical plane, each part having a hollow tubular element (3.1) housed inside an outer housing (3.2) of each half of the insulator, defining in each part an annular space (3.3) comprised between the outer wall of the tubular element (3.1) and the inner wall of the outer housing (3.2), where the secondary or high-voltage winding is disposed, the insulator (3) presenting in its outer housing (3.2) a slot (5), which is situated at zero volts level, and though which the oil penetrates towards the secondary winding.

A method is provided for manufacturing a transformer. The method includes preparing a core, a first coil portion that covers at least part of the core, and a second coil portion that covers a periphery of the first coil portion perpendicular to a central axis of winding of the first coil portion. The first and second coil portions each include a bobbin and a coil wound therearound. The coil of the first or second coil portion is an edgewise coil. The method also includes: screwing the bobbin and coil of the first coil portion with each other, and screwing the bobbin and coil of the second coil portion with each other; and attaching the second coil portion to the outside of the first coil portion perpendicular to the central axis of winding of the first coil portion, and attaching the core to sandwich the first and second coil portions in an axial direction of the first coil portion.

In an embodiment, an inductive component includes at least one electrical conductor, a coil former with a hollow-shaped winding former, on a surface of which the at least one electrical conductor is wound around the winding former, a magnetic core arranged in a first cavity of the winding former and a potting material, wherein the at least one electrical conductor is surrounded by the potting material, wherein the potting material has no directly adherent contact with the magnetic core, wherein the magnetic core comprises a first part-body and a second part-body, which are connected to one another, wherein at least one of the first part-body or the second part-body of the magnetic core comprises a leg arranged in the first cavity of the winding former and at least one further leg arranged outside the first cavity of the winding former.

A method of assembling the ignition coil assembly including a first spool, a first coil, and a second spool. The first coil is wound around a first spool outer surface. The first spool and the first coil are disposed within a cavity of the second spool and an electrically insulating material injected into an annular space defined between a first coil outer surface and a second spool inner surface. The first spool is configured to allow a decrease of a circumference of the first spool when the first coil is wound around an outer surface of the first spool. Decreasing the circumference of the first spool increases the annular space sufficient to inject the electrically insulating material into the annular space without creating substantial voids in the electrically insulating material.

A transformer in which the high-voltage and low-voltage coils are easily laminated when they are alternately laminated in their axial directions, improving power efficiency. The transformer includes: a high-voltage coil including a wire wound around a cylindrical winding drum of a bobbin which is provided with flanges on both ends of the winding drum; a low-voltage coil formed of a flat plate member having an open ring shape, the low-voltage and high-voltage coils being alternately laminated in their axial directions; and a cover member which has a ring plate shape and is coaxially laminated on an outside of a laminate in an axial direction. The low-voltage coil is between the high-voltage coil and the cover member, and a wall portion protruding in the axial direction from the bobbin of the high-voltage coil and a wall portion protruding in the axial direction of the cover member are alternately disposed.