A magnetic pole piece device disposed between an inner diameter side magnet field and an outer diameter side magnet field of a magnetic gear, includes: an outer circumferential cover member disposed opposite to the outer diameter side magnet field and having a cylindrical shape; an inner circumferential cover member disposed opposite to the inner diameter side magnet field and having a cylindrical shape; and a plurality of magnetic pole pieces disposed at intervals in a circumferential direction between the outer circumferential cover member and the inner circumferential cover member. The outer circumferential cover member includes a plurality of outer circumferential side facing portions facing outer circumferential surfaces of the plurality of magnetic pole pieces, and a plurality of outer circumferential side connecting portions for connecting two adjacent outer circumferential side facing portions of the plurality of outer circumferential side facing portions.

A planar member for a stator stack comprises a stator yoke defining a central longitudinal axis, a first surface facing radially outward, and a second surface facing radially inward, a tooth extending radially inwards from the second surface, a first tooth tip extending circumferentially from a radially inward end of the tooth, a second tooth tip extending circumferentially from the radially inward end of the tooth, a first slot portion defined between the first tooth tip and the second surface, a second slot portion defined between the second tooth tip and the second surface, and a slot cooling fin extending radially from the stator yoke into the first slot portion.

A planar member for a stator stack comprises a stator yoke defining a central longitudinal axis, a first surface facing radially outward, and a second surface facing radially inward, a tooth extending radially inwards from the second surface, a first tooth tip extending circumferentially from a radially inward end of the tooth, a second tooth tip extending circumferentially from the radially inward end of the tooth, a first slot portion defined between the first tooth tip and the second surface, a second slot portion defined between the second tooth tip and the second surface, and a slot cooling fin extending radially from the stator yoke into the first slot portion.

A stator includes: a stator core including a plurality of stator teeth in a circumferential direction with respect to a center of rotation of a rotary electric machine; a stator coil disposed on a bottom portion side of each of a plurality of stator slots formed between the stator teeth; and a stator magnet disposed on an opening side of each of the plurality of stator slots and having the same polarity in a radial direction, and in each of the stator slots, the stator magnet is divided at a center in the circumferential direction of the stator slot.

A stator includes: a stator core including a plurality of stator teeth in a circumferential direction with respect to a center of rotation of a rotary electric machine; a stator coil disposed on a bottom portion side of each of a plurality of stator slots formed between the stator teeth; and a stator magnet disposed on an opening side of each of the plurality of stator slots and having the same polarity in a radial direction, and in each of the stator slots, the stator magnet is divided at a center in the circumferential direction of the stator slot.

An electrical rotating machine includes a laminated stator core having a first axial duct to convey a cooling air stream generated by a turbomachine through the laminated stator core to a rear stator winding overhang, and a second axial duct to return the cooling air stream from the rear stator winding overhang back through the laminated stator core. An air guide is attached to the laminated stator core on a side of the rear stator winding overhang to redirect the cooling air stream via the rear stator winding overhang. Radial slots between the ducts and an air gap between the laminated stator core and a rotor are spaced from one another at an axial distance which decreases toward a turbomachine-distal side of the laminated stator core so as to compensate a temperature gradient caused by the one-sided cooling.

An electrical rotating machine includes a laminated stator core having a first axial duct to convey a cooling air stream generated by a turbomachine through the laminated stator core to a rear stator winding overhang, and a second axial duct to return the cooling air stream from the rear stator winding overhang back through the laminated stator core. An air guide is attached to the laminated stator core on a side of the rear stator winding overhang to redirect the cooling air stream via the rear stator winding overhang. Radial slots between the ducts and an air gap between the laminated stator core and a rotor are spaced from one another at an axial distance which decreases toward a turbomachine-distal side of the laminated stator core so as to compensate a temperature gradient caused by the one-sided cooling.

Electronic devices are disclosed including hydrophobic or oleophobic coatings that control coolant flow therein or thereon. In at least one embodiment, an electric machine is provided including a stator core defining a cavity, windings disposed within the cavity and including end windings protruding from the cavity, and one or more layers of an oleophobic coating overlying the end windings and configured to control a flow of coolant over the end windings. A method may include applying one or more layers of a oleophobic coating to end windings of an electric machine stator such that the one or more layers control a flow of coolant over the end windings. The one or more layers may define coolant flow paths, which may direct coolant to areas of the electric machine requiring additional cooling, such as hot spots or neutral points.

Electronic devices are disclosed including hydrophobic or oleophobic coatings that control coolant flow therein or thereon. In at least one embodiment, an electric machine is provided including a stator core defining a cavity, windings disposed within the cavity and including end windings protruding from the cavity, and one or more layers of an oleophobic coating overlying the end windings and configured to control a flow of coolant over the end windings. A method may include applying one or more layers of a oleophobic coating to end windings of an electric machine stator such that the one or more layers control a flow of coolant over the end windings. The one or more layers may define coolant flow paths, which may direct coolant to areas of the electric machine requiring additional cooling, such as hot spots or neutral points.

An electric motor apparatus is described that utilizes a Halbach array and a ferrofluid core. The electric motor comprises a rotor assembly and a stator assembly, each of which utilizes a Halbach array. A ferrofluid core is utilized in the stator, which results in a motor that is less susceptible to core loss and operates with increased efficiency.