An electric motor includes an inner rotor unit including a rotary body having an outer ring portion and multiple magnetic members mounted to the outer ring portion, and a stator unit including multiple alternately arranged first and second stators. Each first stator includes a first magnetic conductive member and a first coil. Each second stator includes a second magnetic conductive member disposed between two adjacent first stators, and a second coil . An imaginary circle is defined to be centered at a central point of the rotary body and to pass through central points of the first coils. The second coil of each of the second stators has a central point that does not lie on the imaginary circle.

An axial flux motor includes a rotor and a plurality of stators. The stators are disposed around the rotor. Each stator includes a magnetic modular body, and a winding. The magnetic modular body includes a magnetic base and a top magnetic member. The magnetic base has an armature core surrounded by the winding, and a first connecting portion disposed on the armature core. The top magnetic member has a second magnetic face, and a second connecting portion that is disposed on the second magnetic face and that engages complementarily to the first connecting portion. The top magnetic member is connected to the armature core through an inter-engagement of the first and second connecting portions.

Disclosed is a linear motor that can exert a high propulsive force and reduce cogging. A stator has a plurality of core units in a stroke direction. Each of the core units has a first core having a first magnetic pole and a second magnetic pole, which is different in polarity from the first magnetic pole, coils wound around the first core, a second core having a third magnetic pole and a fourth magnetic pole, which is different in polarity from the third magnetic pole, and coils wound around the second core. The third magnetic pole faces the first magnetic pole, and the fourth magnetic pole faces the second magnetic pole. A movable element is sandwiched between the first magnetic poles and the third magnetic poles, and between the second magnetic poles and the fourth magnetic poles.

The purpose of the present invention is to provide an electric generator which allows the magnitude of mutual magnetic action between a rotor and an armature to be self-adjusted in the electric generator against a fluctuation in a motive power or a fluctuation in an electric load, such that the magnitude of an induced electromotive force is controlled to compensate, with voltage variation, for amounts of the fluctuation in the motive power and the fluctuation in the electric load and to induce electricity with a uniform frequency from the electric generator, while stabilizing the prime mover or load devices, and parts optimized for the same. To this end, the present invention has an iron-piece structure in which the rotor and the armature of the electric generator mutually correspond to each other in a concave-convex structure, and the present invention is configured to be able to control the magnitude of the induced electromotive force, as the armature moves in the axial direction in response to a change in the rotation speed, output voltage, or frequency of the electric generator and, thereby, variably controls a mutually corresponding length of the concave-convex structure.

Disclosed is a yoke-less mover of a homopolar linear synchronous machine. The yoke-less mover may include a cold plate having slots. Ferromagnetic cores are fixed to the cold plate. Each of the ferromagnetic cores may protrude through a respective one of the slots, creating gaps between the ferromagnetic cores. Armature windings are fixed to the cold plate. The armature windings may occupy the gaps between the ferromagnetic cores. The ferromagnetic cores of the yoke-less mover have better ferromagnetic utilization and lower weight. It also enables more flexible topologies in the armature windings.

To reduce a loss of a rotating electric machine by making it difficult for an eddy current to occur in a welding portion of the rotating electric machine. A rotating electric machine includes a rotor including a magnet on an outer circumferential portion, a stator core having plural teeth facing the outer circumferential portion of the rotor via a gap, an electric insulator covering a part of a surface of the stator core, and plural coils wound around the stator core via the electric insulator. The stator core has plural steel plates stacked in an axial direction. At least two plural steel plates [adjacent to each other in the axial direction, of the plural steel plates, are welded at a position on the surface of the stator core, the position being outside a closed magnetic circuit generated in the stator core. The plural steel plates are not welded at a position on the surface of the stator core where each tooth faces the rotor.

A stator assembly including at least one pair of c-shaped stator cores, each c-shaped stator core having a bobbin, and a winding wound around each bobbin, wherein the windings on each adjacent pair of c-shaped stator cores are wound in opposite directions.

The disclosure relates to a rotor for an electrical machine having internal permanent magnets including a yoke consisting of a stack of sheets defining a plurality of recesses for receiving parallelepipedal permanent magnets, the recesses being surrounded by magnetically saturated external transverse isthmuses, by radial isthmuses, lateral isthmuses and oblique isthmuses, wherein the magnets are assembled in pairs of magnets magnetized in the same direction and perpendicular to the radial direction of the radial isthmuses arranged between the coupled magnets, the radial isthmuses having a thickness of less than 5% of the diameter of the rotor, and the perimeter of the cross section of the rotor is formed by a succession of curved profiles, between two consecutive pairs of magnets, and tangential linear profiles at the external transverse isthmuses. The disclosure also relates to the application of such a rotor for creating a motor, in particular a motor for a turbo compressor, or an electrical generator.

Apparatus for use as a motor or generator, comprising: a first part; a second part movable relative to the first part and spaced from the first part by an air gap; and a plurality of spaced electromagnet elements (120) provided on the first part, each electromagnet element being operative to apply a magnetic field in the air gap in response to application of an electric current; wherein each electromagnet element comprises: a pole piece comprising: an outer section (124 A, 124B) defining an elongate air-gap facing surface (125 A) of area A.sub.1, perimeter P.sub.1, lateral width W.sub.1, and longitudinal length L.sub.1, wherein Li is greater than W1; and a coil-winding section of cross-sectional area A.sub.2, cross-sectional perimeter P.sub.2, lateral width W.sub.2, and longitudinal length L.sub.2; and an electrically conductive coil (128) wound around the coil-winding section of the pole piece; characterised in that P.sub.2 is less than P.sub.1 and in that W.sub.2 is substantially equal to L.sub.2.

A stator for an electric motor is described. An example stator includes a stator core having teeth that are radially arranged about a common central axis of the stator and located in a spaced apart manner from one another. Each tooth has an inward portion and an outward portion. The example stator further includes an electrically transmissive coil of wire that is wound contiguously upon the inward portions of at least a subset of teeth from the plurality of teeth. The stator also includes wedge members that are radially arranged about the common central axis and located intermittently with the plurality of teeth such that each wedge member abuts with the outward portions of adjacently located teeth.