An annular axial flux motor includes a rotor mounted on an annular subsection of a rotatable cam ring and a stator mounted on an annular subsection of a carrier frame. The rotor includes two Halbach arrays of permanent magnets spaced from each other on the cam ring along an axial direction. The stator includes multiple phase electrical windings printed on multiple layers of a printed circuit board (PCB) that are stacked along the axial direction. The multiple layers are positioned between the Halbach arrays, with active side of the Halbach arrays facing to opposite sides of the multiple layers. The Halbach arrays are configured to generate a symmetrical magnetic field and the multiple phase electrical windings are configured to have a same rotor-dependent torque constant, such that the stator can generate a constant torque to rotate the rotor and the cam ring within a finite travel range.

An annular axial flux motor includes a rotor mounted on an annular subsection of a rotatable cam ring and a stator mounted on an annular subsection of a carrier frame. The rotor includes two Halbach arrays of permanent magnets spaced from each other on the cam ring along an axial direction. The stator includes multiple phase electrical windings printed on multiple layers of a printed circuit board (PCB) that are stacked along the axial direction. The multiple layers are positioned between the Halbach arrays, with active side of the Halbach arrays facing to opposite sides of the multiple layers. The Halbach arrays are configured to generate a symmetrical magnetic field and the multiple phase electrical windings are configured to have a same rotor-dependent torque constant, such that the stator can generate a constant torque to rotate the rotor and the cam ring within a finite travel range.

In a wheel drive apparatus, a clutch is configured to switch a coupling mode between a first rotating shaft of a first rotating electrical machine and a second rotating shaft of a second rotating electrical machine to any one of (i) a power transmission mode in which power transmission is enabled between the first rotating shaft and the second rotating shaft; and (ii) a power interruption mode in which power transmission is interrupted between the first rotating shaft and the second rotating shaft.

A rotor rotatable about a center axis extending in an axial direction. The rotor includes an annular rotor core, a rotor magnet fixed to an inner surface of the rotor core in a radial direction, and a protection portion that presses the rotor magnet against the rotor core from an inside in the radial direction, and fixes the rotor core and the rotor magnet.

A spindle shaft device including a shaft, a first torque sensor, and a second torque sensor. The shaft extends along an axial direction and comprises a first side portion, a second side portion, and a central portion located between the first side portion and the second side portion. The central portion has a central torsional rigidity with respect to the axial direction. The first side portion has a first torsional rigidity with respect to the axial direction. The second side portion has a second torsional rigidity with respect to the axial direction. The first torsional rigidity is smaller than the central torsional rigidity. The second torsional rigidity is smaller than the central torsional rigidity. The first torque sensor is disposed on the first side portion. The second torque sensor is disposed on the second side portion.

One aspect of a rotor of the present invention includes: a rotor core rotatable about a central axis; and a rotor magnet fixed to an outer peripheral surface of the rotor core. The rotor magnet has a plurality of magnetized portions arranged along a circumferential direction in a Halbach array. The plurality of magnetized portions include a plurality of radially magnetized portions whose magnetization direction is a radial direction and a plurality of non-radially magnetized portions whose magnetization direction is different from the radial direction. The rotor core is a non-magnetic member that has a hole, recessed from a surface on one side in an axial direction of the rotor core to the other side in the axial direction and is made of a non-magnetic material. The hole is located on the radially inner side of the radially magnetized portion.

One aspect of a rotor of the present invention includes: a rotor core rotatable about a central axis; and a rotor magnet fixed to an outer peripheral surface of the rotor core. The rotor magnet has a plurality of magnetized portions arranged along a circumferential direction in a Halbach array. The plurality of magnetized portions include a plurality of radially magnetized portions whose magnetization direction is a radial direction and a plurality of non-radially magnetized portions whose magnetization direction is different from the radial direction. The rotor core is a non-magnetic member that has a hole, recessed from a surface on one side in an axial direction of the rotor core to the other side in the axial direction and is made of a non-magnetic material. The hole is located on the radially inner side of the radially magnetized portion.

A rotating electric machine is provided with a field magnet having a magnet unit including a plurality of magnetic poles having alternating polarities in a circumferential direction and a magnet supporting section having a cylindrical shape to which the magnet unit is fixed, and an armature having a multi-phase armature winding, disposed facing the magnet unit, either one of the field magnet or the armature being configured as a rotor. The magnet unit is configured annularly along the circumferential direction. The magnet unit is fixed to a fixed surface which is either an outer peripheral surface or an inner peripheral surface of the magnet supporting section via a foamable resin, and a thickness dimension of the foamable resin in a radial direction is set to be differentiated depending on a distance from the fixed surface of the magnet supporting section to an anti-armature side circumferential surface of the magnet.

A multi-degree-of-freedom electromagnetic machine includes a spherical structure, a first coil, a second coil, a non-magnetic structure, and a Halbach array. The spherical structure has a first axis of symmetry, a second axis of symmetry, and a third axis of symmetry, and the first, second, and third axes of symmetry are disposed perpendicular to each other. The first coil is wound on the spherical structure about the first axis of symmetry, and the second coil is wound on the spherical structure about the second axis of symmetry. The non-magnetic structure is spaced apart from, and at least partially surrounds, the spherical structure. The Halbach array is mounted on the non-magnetic structure and includes N-magnets, where N is a multiple of 4. The spherical structure and non-magnetic structure are mounted to allow relative rotation between the non-magnetic structure and the spherical structure.

The present invention relates to a rotor of motor, and more particularly, to a 2-segment quasi-Halbach rotor of motor that includes a radial magnet and a circumferential magnet which are Halbach-arrayed and a back iron providing a flux to reduce a thickness of the magnet and acquire high air-gap flux density.