A rotor of a motor includes first and second rotor cores, a field magnet, and a commutator magnet. The first and second rotor cores each include a core base and a plurality of claw poles. The claw poles of the first rotor core and the claw poles of the second rotor core are alternately arranged in a circumferential direction. The field magnet is located between the core bases. The field magnet is magnetized in an axial direction so that the claw poles of the first rotor core and the claw poles of the second rotor core function as different magnetic poles in the circumferential direction. The commutator magnet is located on an outer circumference of the field magnet around the claw poles. The commutator magnet is magnetized so that surfaces having the same polarity face each other between the claw poles and the commutator magnet.

A motor includes a stator having a winding, and a rotor. The rotor rotates by receiving a rotational magnetic field generated by drive current supplied to the winding. The winding includes a first winding and a second winding, the first and second windings both being excited at the same timing by the drive current. The first winding and the second winding are connected in series. The rotor includes a first pole section and a second pole section. The second pole section faces the second winding at the rotation position of the rotor at which the first pole section faces the first winding. The magnetic force exerted on the stator by the second pole section is weaker than that exerted by the first pole section.

A technique by which the magnetic flux of the magnetic pole facing the stator of the magnet can be further increased in a rotor, is provided. An electric motor according to the present disclosure includes a stator 10; a rotor 20 facing the stator 10 in an axial direction (first direction) and configured to be rotatable in a circumferential direction (second direction) that is orthogonal to the axial direction; and a short-circuit reduction member 25, 26, wherein the rotor 20 includes a main magnet 22 having a first magnetic pole on a surface facing the stator 10; an auxiliary magnet 23, 24 arranged adjacent to the main magnet 22 and having a second magnetic pole and a third magnetic pole that is different in polarity from the second magnetic pole, and configured to increase a magnetic flux of the first magnetic pole, and wherein the auxiliary magnet 23, 24 is arranged adjacent to the main magnet 22 in a radial direction (third direction) that is orthogonal to the axial direction, and the short-circuit reduction member 25, 26 is provided at a portion around the auxiliary magnet 23, 24 facing the auxiliary magnet 23, 24 in parallel with a virtual line connecting the second magnetic pole and the third magnetic pole, to reduce a short-circuit of a magnetic flux between the second magnetic pole and the third magnetic pole.

A reduction gearbox which has: an input, which can be coupled to an input shaft, which has an input speed; an output, which rotates at an output speed that is lower than the input speed; and at least one statically arranged component. It is envisaged that an electric generator is integrated into the reduction gearbox, said generator comprising a rotor and a stator, wherein the rotor of the electric generator is coupled to the output of the reduction gearbox, and the stator of the electric generator is coupled to a statically arranged component of the reduction gearbox.

An electric motor for reciprocating an object along a rod having a predetermined length is provided, comprising: a housing; a rotor unit that is mounted to the inside of the housing via a bearing to be rotatable and comprises a rotor shaft, which is axially-coupled to the rod to linearly reciprocate along the rod during rotation, and a plurality of magnets mounted along the circumference direction of the rotor shaft; and a stator unit comprising at least one stator core and a coil, the at least one stator core comprising a yoke portion of a closed loop shape that is built in the housing so as to surround the circumference of the rotor unit, and a plurality of slot portions extending from the yoke portion toward the rotor, and the coil being wound around at least one slot portion among the plurality of slot portions.

An electric motor for reciprocating an object along a rod having a predetermined length is provided, comprising: a housing; a rotor unit that is mounted to the inside of the housing via a bearing to be rotatable and comprises a rotor shaft, which is axially-coupled to the rod to linearly reciprocate along the rod during rotation, and a plurality of magnets mounted along the circumference direction of the rotor shaft; and a stator unit comprising at least one stator core and a coil, the at least one stator core comprising a yoke portion of a closed loop shape that is built in the housing so as to surround the circumference of the rotor unit, and a plurality of slot portions extending from the yoke portion toward the rotor, and the coil being wound around at least one slot portion among the plurality of slot portions.

An axial flux motor includes a housing and a rotor assembly rotatably secured to the housing. The rotor assembly includes a body having first and second opposed faces and defining an axis of rotation and plurality of rotor poles including a first rotor pole and a second rotor pole. The first rotor pole and the second rotor pole cooperatively define an axially extending pocket circumferentially therebetween. The rotor assembly further includes a plurality of spaced apart magnets extending from the first face, a first magnet of the plurality of magnets being positioned within the axially extending pocket. The axial flux motor further includes a coreless stator assembly fixedly secured to the housing, the coreless stator assembly including a supporting platform and a plurality of coils attached on the supporting platform.

An axial gap motor having a rotor and a stator core. A plurality of pressed powder teeth extends in a radial direction of the stator core and each has a trapezoidal shape in which a circumferential length of a pressed-powder-tooth-radial-direction-outer-end portion is larger than a circumferential length of a pressed-powder-tooth-radial-direction-inner-end portion. The rotor includes a plurality of field magnets, each configured such that a circumferential length of a magnet-radial-direction-inner-end portion is greater than or equal to a circumferential length of a magnet-radial-direction-outer-end portion. When the rotor and the stator core rotate relative to each other about a rotation axis, a part of the field magnets first overlaps with pressed-powder-tooth-radial-direction-inner portions of pressed powder teeth, and while the field magnets are located at a q-axis position with respect to the pressed powder teeth, adjacent ones of the field magnets individually overlap with one pressed powder tooth.

Construction of a permanent magnet rotor assembly having a plurality of magnetic poles and comprising a number of magnetic pole pieces arranged in circular array. Two sets of permanent magnets—one set magnetised in circumferential direction of the rotor and the second set providing flux in axial direction of rotor, generating a magnetic flux focused through the pole piece and interacting with the magnetic flux of the stator. End-plates made of magnetic material are present such there is an axial gap between the them and the array of magnetic pole pieces. Circumferentially magnetised magnets are placed in the circumferential gaps between the pole pieces, whereas the magnets providing flux in axial direction are placed in the gaps between the array of pole pieces and end-plates.

Construction of a permanent magnet rotor assembly having a plurality of magnetic poles and comprising a number of magnetic pole pieces arranged in circular array. Two sets of permanent magnets—one set magnetised in circumferential direction of the rotor and the second set providing flux in axial direction of rotor, generating a magnetic flux focused through the pole piece and interacting with the magnetic flux of the stator. End-plates made of magnetic material are present such there is an axial gap between the them and the array of magnetic pole pieces. Circumferentially magnetised magnets are placed in the circumferential gaps between the pole pieces, whereas the magnets providing flux in axial direction are placed in the gaps between the array of pole pieces and end-plates.