A motor includes a rotor having a shaft, a rotor core, and a permanent magnet, and a stator surrounding the rotor. The permanent magnet forms a magnet magnetic pole, a part of the rotor core forms a virtual magnetic pole. The motor includes first and second bearings support the shaft, and further includes first and second bearing support portions. Of the first and second bearings, the first bearing is located on the load side. A distance D1 from the center axis to the inner circumferential surface of the first bearing support portion, a distance D2 from the center axis to the inner circumferential surface of the second bearing support portion, a distance d1 from the center axis to the outer circumferential surface of the first bearing, and a distance d2 from the center axis to the outer circumferential surface of the second bearing satisfy D1−d1<D2−d2.

The invention reduces tensile stress generated in the rotor core in a radial direction when a rotor core and a rotor support member are joined. A region in an axial direction (L) in which a melted joint portion (W2) for joining a rotor core (2) and a rotor support member (9) is formed is set as an axial joint region (JR). Among a plurality of corner portions (4c) of the permanent magnet (4), at least one corner portion (4c) that overlaps with the axial joint region (JR) when seen in a radial direction and that faces an outer peripheral surface (CP2) of the rotor core (2) is set as a specific corner portion (4s). Among facing surface portions (5p) of an inner wall portion of the magnet insertion hole (5) that face the corner portions (4c), the facing surface portion (5p) that faces the specific corner portion (4s) is set as a specific facing surface portion (5s). A clearance (G) formed between the specific corner portion (4s) and the specific facing surface portion (5s) is larger than a clearance formed between another corner portion (4c) and another facing surface portion (5p).

A retention structure can be created using two or more different materials (e.g., one magnetic material, and one non-magnetic material) as a composite structure. The retention structure can include a cylindrical hoop comprising one or more one or magnetic regions tangentially alternating with one or more non-magnetic regions configured to surround and retain a plurality of magnets to a rotor, wherein the one or more magnetic regions are aligned with each one of the plurality of magnets and the one or more non-magnetic regions are aligned with one or more spaces between the plurality of magnets on the rotor. The magnetic material allows flux from the permanent magnets to flow through to the stators and the non-magnetic sections reduce leakage of magnetic flux to adjoining permanent magnets through use of non-magnetic materials. The retention structure can be fabricated using a hot isostatic press process.

A retention structure can be created using two or more different materials (e.g., one magnetic material, and one non-magnetic material) as a composite structure. The retention structure can include a cylindrical hoop comprising one or more one or magnetic regions tangentially alternating with one or more non-magnetic regions configured to surround and retain a plurality of magnets to a rotor, wherein the one or more magnetic regions are aligned with each one of the plurality of magnets and the one or more non-magnetic regions are aligned with one or more spaces between the plurality of magnets on the rotor. The magnetic material allows flux from the permanent magnets to flow through to the stators and the non-magnetic sections reduce leakage of magnetic flux to adjoining permanent magnets through use of non-magnetic materials. The retention structure can be fabricated using a hot isostatic press process.

A rotor of electric motor is described comprising: a disc with a major surface and a rotation axis (X), the major surface of the disc comprising a circular recess in which a circular band or ring of material is arranged, the material being capable of magnetizing itself under the action of a magnetizing magnetic field, and internally partitioned into areas electrically isolated from one another, a circular series of permanent magnets arranged about the rotation axis (X) and resting on the circular band, a grid fixed to the disc for maintaining the position of the magnets on the disc.

A laminated rotor core for a rotor of a permanently excited electric machine and to a method for producing same are provided. The laminated rotor core consists of a plurality of stacked lamination rings, each lamination ring consisting of a plurality of circular segments. Each circular segment has multiple receiving openings, which are arranged in a V-shaped manner relative to each other in pairs, for permanent magnets and multiple passages for respective fixing elements. The laminated rotor core is mounted on a holding disc using the fixing elements, which run in the passages of the laminated rotor core.

A rotor arrangement for an electric motor is disclosed. The rotor arrangement comprises a first rotor comprising a hollow cylinder and a cylindrical rotor stack shrink-fitted onto the hollow cylinder. The first rotor comprises a first end plate attached to a first end portion of the hollow cylinder. The rotor arrangement further comprises a rotor shaft comprising a first shaft member and a second shaft member arranged coaxially to the first shaft member. The first shaft member is connected to a connection portion of the first end plate. The rotor arrangement comprises a second rotor connected to the second shaft member. The present disclosure further relates to an electric propulsion motor arrangement, a vehicle, and a set of rotors for electric motors.

A rotor arrangement for an electric motor is disclosed. The rotor arrangement comprises a first rotor comprising a hollow cylinder and a cylindrical rotor stack shrink-fitted onto the hollow cylinder. The first rotor comprises a first end plate attached to a first end portion of the hollow cylinder. The rotor arrangement further comprises a rotor shaft comprising a first shaft member and a second shaft member arranged coaxially to the first shaft member. The first shaft member is connected to a connection portion of the first end plate. The rotor arrangement comprises a second rotor connected to the second shaft member. The present disclosure further relates to an electric propulsion motor arrangement, a vehicle, and a set of rotors for electric motors.

A fan for use in agriculture which has a BLDC motor which allows for varying the speed of the fan to vary the airflow rate of the fan and vary the efficiency of the fan. A ventilation system for use in a livestock confinement building to maximize a rate of growth of the livestock. A process for maximizing the growth of livestock in a livestock confinement building by controlling the airflow in the livestock confinement building.

Systems and methods for connecting rotors between multiple permanent magnet motors. By coupling the rotors of multiple modules, torque may be transferred while maintaining the angular alignment between the stator and rotor magnetic fields of each individual permanent magnet motor.