A printed coil assembly including a flexible dielectric material, a patterned top conductive layer formed on a top surface of the flexible dielectric material, and a patterned bottom conductive layer formed on a bottom surface of the flexible dielectric material. The patterned top conductive layer and the patterned bottom conductive layer form a plurality of printed coils arranged in a plurality of printed coil rollers concentrically arranged in a cylindrical shape. Each of the plurality of printed coils includes a top layer printed coil disposed within the patterned top conductive layer and a bottom layer printed coil disposed within the patterned bottom conductive layer. Coil pitches of the coils within each roller are chosen such that corresponding ones of the plurality of printed coils in adjacent rollers are axially aligned relative to a center of the cylindrical shape.

A printed coil assembly including a flexible dielectric material, a patterned top conductive layer formed on a top surface of the flexible dielectric material, and a patterned bottom conductive layer formed on a bottom surface of the flexible dielectric material. The patterned top conductive layer and the patterned bottom conductive layer form a plurality of printed coils arranged in a plurality of printed coil rollers concentrically arranged in a cylindrical shape. Each of the plurality of printed coils includes a top layer printed coil disposed within the patterned top conductive layer and a bottom layer printed coil disposed within the patterned bottom conductive layer. Coil pitches of the coils within each roller are chosen such that corresponding ones of the plurality of printed coils in adjacent rollers are axially aligned relative to a center of the cylindrical shape.

An electromagnetic coil where a conductive member is wound so as to surround an air core region includes an effective coil portion, a first coil end portion, and a second coil end portion. The effective coil portion is formed of a coil-use conductive wire formed by bundling a plurality of conductive base members, the first coil end portion is formed of a first end member that is made of a solid conductive material, and the second coil end portion is formed of a second end member made of a solid conductive material. In the air core region of “one magnetic material” to which an electric current of a first phase is supplied, the effective coil portion of “the other electromagnetic coil” to which an electric current of a second phase is supplied is fitted.

A stator for interacting with magnets carried by a rotor of an electric machine, the stator comprising: an active region arranged to be aligned with the magnets carried by the rotor; a first inactive region and a second inactive region, wherein the first and second inactive regions are separated by the active region; and a slotless phase winding comprising a plurality of conductive elements, wherein each conductive element comprises a conductor provided in an insulating housing, and wherein the slotless phase winding is arranged in a serpentine structure comprising: a first active segment in which the conductive elements extend across the active region from the first inactive region to the second inactive region; a second active segment in which the conductive elements extend across the active region from the second inactive region to the first inactive region; and an inactive segment coupling the first active segment to the second active segment, wherein the inactive segment comprises a turn provided in the second inactive region, and wherein at least one of the conductive elements is twisted in the second inactive region.

A slot-less motor includes a rotor and a stator which is equipped with a coil assembly made of a combination of a plurality of coils. Each of the coils is designed as an air core coil which includes a pair of effective coil portions and a pair of coil ends. The coils assembly has the effective coil portions each of which is disposed in air cores of the respective adjacent coils. The coils include first coils each of which is not located between a center line and each of outer outlines of a respective adjacent one of the first coils.

One variation of a system for an electric motor includes a rotor including magnetic elements within a body. The system also includes a stator including coil assemblies arranged about the rotor. Each coil assembly includes an outer hook element and an inner hook element. The outer hook element extends across a first axial face and an outer radial surface of the rotor. The inner hook element: extends across a second axial face of the rotor; extends partially across the inner radial surface of the rotor; and is coupled to the outer hook element to define a throat configured to locate the rotor within the coil assembly. The system includes a shaft coupled to the inner radial surface of the rotor. Furthermore, the system includes a controller configured to drive current through the coil assemblies to generate a toroidal magnetic field configured to couple the magnetic elements to rotate the rotor.

A motor includes a rotor, a stator that surrounds the radial outer side of the rotor, a housing that contains the rotor and the stator, a holder axially above the stator, a substrate fixed to the axial upper side of the holder, and a connector radially outward of the housing and electrically connected to the substrate. The holder includes a holder body, and a holder protrusion that connects to the holder body and extends radially outward from the housing. The connector contacts the underside of the holder protrusion.

A motor includes a rotor, a stator that surrounds the radial outer side of the rotor, a housing that contains the rotor and the stator, a holder axially above the stator, a substrate fixed to the axial upper side of the holder, and a connector radially outward of the housing and electrically connected to the substrate. The holder includes a holder body, and a holder protrusion that connects to the holder body and extends radially outward from the housing. The connector contacts the underside of the holder protrusion.

A coil with a distributed winding formed from hairpins that each have two straight-line conductor portions arranged in different slots of a coil body. Contact regions shaped in circumferential direction adjoin the conductor portions at one axial end and are connected at the other axial end through a turning region. The contact regions have at the end remote of the coil body a connection portion that are aligned in radially extending rows. The contact regions of a layer are shaped in the same circumferential direction. A portion of the contact regions of an outer layer is deformed in radial direction to form an additional, and these contact regions are shaped in a circumferential direction opposite to the contact regions of the outer layer.

A coil with a distributed winding formed from hairpins that each have two straight-line conductor portions arranged in different slots of a coil body. Contact regions shaped in circumferential direction adjoin the conductor portions at one axial end and are connected at the other axial end through a turning region. The contact regions have at the end remote of the coil body a connection portion that are aligned in radially extending rows. The contact regions of a layer are shaped in the same circumferential direction. A portion of the contact regions of an outer layer is deformed in radial direction to form an additional, and these contact regions are shaped in a circumferential direction opposite to the contact regions of the outer layer.