A rotor for an electric motor includes: a rotating element extending along an axis; and a retaining body formed of metal and configured to hold the rotating element from an outer peripheral side, where the retaining body includes: a plurality of annular members annularly surrounding an outer peripheral surface of the rotating element and arranged at intervals in the axis direction; and a plurality of connecting members arranged in a circumferential direction between the annular members adjacent to each other so as to connect the annular members. As a result, a path of eddy current is limited and the eddy current can be reduced.

A spherical electromagnetic machine includes a spherical stator, a plurality of longitudinal slots, a plurality of latitudinal slots, a plurality of longitudinal coils, a plurality of latitudinal coils, a first hemispherical shell rotor, and a second hemispherical shell rotor. The longitudinal slots and latitudinal slots are formed in, and are spaced evenly around, the outer surface. The longitudinal coils are disposed within a different one of the longitudinal slots. The latitudinal coils are disposed within a different one of the latitudinal slots. The first and second hemispherical shell rotors are mounted for rotation relative to the spherical stator body and have magnets on their inner surfaces. A Lorentz force causes movement of the first and second hemispherical shell rotors when electrical current is supplied to one or more of the longitudinal coils or to one or more of the latitudinal coils.

Embodiments involve rotors for axial flux induction rotating electric machines that use a soft magnetic composite for the rotor core. A first embodiment is directed to a rotor for a rotating electrical machine that transmits magnetic flux parallel to a shaft of the rotor. The rotor includes a rotor winding and a plurality of cores. The rotor winding consists of a solid piece of conductive material that comprises a plurality of cavities. Each core is placed in a respective cavity and comprises a highly resistive isotropic ferromagnetic powder.

A rotor for a rotary electric machine, including: a stack of magnetic laminations each having openings, the superposition of these openings within the stack forming slots, at least some of the openings having, on at least part of their periphery, friction reliefs, electrically conducting bars made of a first material, received in at least part of the slots and coming to bear via at least one principal face against said reliefs.

A motor for a rotary compressor, and a compressor and an air conditioner having the motor, are disclosed. The motor includes a stator core and a rotor core. The stator core has a through-hole in a center thereof. The stator core is provided with a plurality of circumferentially spaced stator teeth, and the number of stator teeth is M. The rotor core is rotatably disposed in the through-hole. The rotor core is provided with a plurality of circumferentially spaced rotor slots, and the number of the rotor slots is N, wherein 2≤N−M≤6. A cross-sectional area of the stator core is denoted as S, and a distance between two endpoints of two radially opposite curved segments of an outer edge of the cross section is denoted as L, wherein 0.93≤4*S/3.14/L2≤0.96.

A stator core or a rotor core for an electrical machine, the core including a plurality of teeth separated by slots in a circumferential direction of the core, and a plurality of lamination stacks arranged one after another in an axial direction of the core, and separated from each other in the axial direction by cooling ducts. Each lamination stack includes at its each end in the axial direction at least one slit tooth section providing a discontinuity in the electrical conductivity of the lamination material and thereby reducing eddy current losses at the respective slit tooth section, and between the slit tooth sections at least one regular tooth section.

This invention entails the use of fractal shapes as cores for electromagnets, and a concurrent shape of a fractal for the windings which surround it. The novelty of this invention lies not only with the shaping, but the advantage of such shaping, which includes producing a smaller form factor electromagnet for the same desired magnetic field strength, when compared to a conventional electromagnet. It will be appreciated that a range of devices including electromagnets, based on such fractal shaping, are additionally novel and include but are not limited to solenoid switches, relays, and other devices in which the fractal electromagnets are used to make a change in state of some device.

Embodiments involve rotors for axial flux induction rotating electric machines that use a soft magnetic composite for the rotor core. A first embodiment is directed to a rotor for a rotating electrical machine that transmits magnetic flux parallel to a shaft of the rotor. The rotor includes a rotor winding and a plurality of cores. The rotor winding consists of a solid piece of conductive material that comprises a plurality of cavities. Each core is placed in a respective cavity and comprises a highly resistive isotropic ferromagnetic powder.

Embodiments involve rotors for axial flux induction rotating electric machines that use a soft magnetic composite for the rotor core. A first embodiment is directed to a rotor for a rotating electrical machine that transmits magnetic flux parallel to a shaft of the rotor. The rotor includes a rotor winding and a plurality of cores. The rotor winding consists of a solid piece of conductive material that comprises a plurality of cavities. Each core is placed in a respective cavity and comprises a highly resistive isotropic ferromagnetic powder.

Embodiments involve rotors for axial flux induction rotating electric machines that use a soft magnetic composite for the rotor core. A first embodiment is directed to a rotor for a rotating electrical machine that transmits magnetic flux parallel to a shaft of the rotor. The rotor includes a rotor winding and a plurality of cores. The rotor winding consists of a solid piece of conductive material that comprises a plurality of cavities. Each core is placed in a respective cavity and comprises a highly resistive isotropic ferromagnetic powder.