A steering reaction force apparatus for a vehicle includes: a housing that is openable and closable by a cover unit, a stator unit fixed to an inside of the housing, a rotor unit disposed to face the stator unit and to be rotated by electromagnetic interaction with the stator unit, a transmission shaft unit connected to the rotor unit to rotate in conjunction with the rotor unit, a power transmission unit disposed inside the rotor unit to transmit a rotational force of the transmission shaft unit to a steering shaft, and a retainer unit to support the power transmission unit with respect to the cover unit.

A casting coil for a motor assembly, which is formed in a multi-layer structure, includes: a first coil formed to extend in one direction; a second coil bent to extend from an end of the first coil; a third coil bent to extend from an end of the second coil in a direction parallel to the first coil; and a fourth coil bent to extend from an end of the third coil in a direction parallel to the second coil. The first coil, the second coil, the third coil, and the fourth coil form one layer so that a hollow multi-layer structure is formed. A larger magnetic field can be formed by securing a slot filling factor of 50% or more of a stator in the same motor package.

The torque of a permanent magnet motor is increased. There is provided a permanent magnet type motor with concentrated windings, in which each stator pole has a circumferential pitch of 185° or more in an electric angle. In this motor, the circumferential distribution of the magnetic flux density in an air gap surface of the rotor poles PR of the permanent magnet type has an approximately trapezoidal shape. Moreover, the induced voltages of the concentrated windings of the stator have an approximately trapezoidal waveform. An approximately trapezoidal-shaped waveform current is energized in the concentrated winding of each phase. Even if the magnetic flux density is close to the maximum flux density of the soft magnetic member of the stator, large slot cross-sectional areas of the stator can be secured, thus outputting a large torque.

An electric work machine includes a first brushless motor including a first stator and a first rotor combined with the first stator, and a controller. The first stator includes a first stator core and multiple first coils wound around multiple teeth on the stator core. The controller magnetizes the teeth to cause the first rotor to rotate about a rotation axis. In a plane orthogonal to the rotation axis, the first stator core has the same shape as a second stator core in a second stator used in a second brushless motor in another electric work machine. The first rotor can be combined with the second stator. The first rotor has a different number of poles from a second rotor used in the second brushless motor.

An electric work machine includes a first brushless motor including a first stator and a first rotor combined with the first stator, and a controller. The first stator includes a first stator core and multiple first coils wound around multiple teeth on the stator core. The controller magnetizes the teeth to cause the first rotor to rotate about a rotation axis. In a plane orthogonal to the rotation axis, the first stator core has the same shape as a second stator core in a second stator used in a second brushless motor in another electric work machine. The first rotor can be combined with the second stator. The first rotor has a different number of poles from a second rotor used in the second brushless motor.

A motor for a vehicle may include: a shaft member rotatably installed; a magnet attached to the outside of the shaft member; a cover covering the magnet, and fixing the magnet on the shaft member; and a stator disposed outside the cover and the magnet. A distance between the cover and the stator may be equal to a distance between the magnet and the stator.

A motor for a vehicle may include: a shaft member rotatably installed; a magnet attached to the outside of the shaft member; a cover covering the magnet, and fixing the magnet on the shaft member; and a stator disposed outside the cover and the magnet. A distance between the cover and the stator may be equal to a distance between the magnet and the stator.

A motor improves the accuracy of position estimation of a rotor. The rotor included in the motor includes a rotor core containing a magnetic material, a plurality of magnets located on the rotor core in a rotation direction of the rotor, and a plurality of Hall devices located on a mounting surface to detect a magnetic field from the magnets. The magnets have heights from the mounting surface varying regularly in the rotation direction of the rotor when the rotor has a central axis extending in a vertical direction.

A motor improves the accuracy of position estimation of a rotor. The rotor included in the motor includes a rotor core containing a magnetic material, a plurality of magnets located on the rotor core in a rotation direction of the rotor, and a plurality of Hall devices located on a mounting surface to detect a magnetic field from the magnets. The magnets have heights from the mounting surface varying regularly in the rotation direction of the rotor when the rotor has a central axis extending in a vertical direction.

A stator defines multiple stator poles with associated electrical windings. A rotor includes multiple rotor poles. The rotor is movable with respect to the stator and defines, together with the stator, a nominal gap between the stator poles and the rotor poles. The rotor poles includes a magnetically permeable pole material. The rotor also includes a series of frequency programmable flux channels (FPFCs). Each FPFC includes a conductive loop surrounding an associated rotor pole. The stator and the rotor are arranged such that the electrical windings in the stator induce an excitement current within at least one of the FPFCs during start-up.