Torque is improved in a composite torque rotating electric machine that uses permanent magnets having a low residual magnetic flux density such as ferrite magnets, and includes: a stator comprising armature windings arranged at a fixed interval at multiple positions on the inner periphery; a rotor which has a permanent magnet in a cylindrical core comprising laminated magnetic steel sheets and is arranged inside of the stator; and magnetic flux blocking units provided across the circumferential direction on the outer periphery of the rotor that block the closed loop magnetic flux generated around the stator windings. The magnetic flux blocking units can be multiple permanent magnets, with a non-magnetic body such as an air gap disposed between them. The distance between the permanent magnets and the non-magnetic part can be smaller than the interval at which the armature windings are arranged.

A method for reducing stress concentration on a rotor sleeve during balance cutting comprising: providing an axial protrusion to an outer diameter of a first end cap and a second end cap of a rotor assembly; and radially cutting at least one of the sleeve or the axial protrusion to balance the rotor assembly.

A permanent magnet speed governor having a fixed magnetic gap. The permanent magnet speed governor has an outer magnetic rotor connected to a drive shaft and an inner magnetic rotor connected to a driven shaft, at least one outer permanent magnet being evenly distributed along the circumferential direction of the inner circumferential surface of the outer magnetic rotor, at least one inner permanent magnet being evenly distributed along the circumferential direction of the outer circumferential surface of the inner magnetic rotor, two magnetic pole sides of the inner permanent magnet being respectively fixed to an iron yoke, another two sides each being provided with a magnetically conductive body, one end of the inner magnetic rotor being provided with a magnetic circuit regulator used for moving each magnetically conductive body along the axial direction. Adoption of the fixed magnetic gap structure reduces the difficulty of assembly.

An electric centrifugal pump having a motor housing, a pump head, a containment shell, and a rotor assembly consisting of a pump impeller and a permanent magnet rotor, wherein the pump head with the containment shell defines a wet chamber, in which the rotor assembly is arranged rotationally around a longitudinal motor axis, the containment shell with the motor housing defines a dry chamber, in which a wound stator is arranged, and the permanent magnet rotor is arranged within the stator and a hollow-cylindrical region of the containment shell. Particle accumulations in the region between the containment shell and the permanent magnet rotor cannot occur or can only occur to a very minor extent and that the consequences of impurities in the wet chamber are reduced in order to prevent premature wear or a blockage of the centrifugal pump.

The invention relates to a device for providing a motor that delivers a larger amount of produced energy than the amount required for the operation thereof, eliminating the need for a primary energy supply. The device consists of electromagnets produced with coils of incomplete turns arranged in a stator and permanent magnets arranged in a rotor. When an electric current is applied to the coils of incomplete turns, a force is generated in the magnets, causing the rotor to rotate and generate mechanical energy. The coils of incomplete turns are characterized in that, when the rotor rotates, they allow the magnets of the rotor to pass continuously through said coils.

A rotor for a permanent magnet machine includes first and second axially successive rotor sections each including permanent magnets generating magnetic field having a pole pitch. The rotor includes a first coupling system for connecting the first rotor section to a shaft and a second coupling system for connecting the second rotor section to the shaft or to the first rotor section. The second rotor section is rotatable with respect to the first rotor section by an angle corresponding to the pole pitch in response to releasing the second coupling system so as to set the stator flux-linkages generated by the first and second rotor sections to be substantially zeroes. Thereafter, the permanent magnets do not substantially induce voltages on the stator windings even if the rotor is rotating during for example an internal fault of stator windings.

A control circuit switches over a shift range by controlling driving of a motor to rotationally drive a detent plate. A current detection circuit detects a current value corresponding to a driving current supplied to drive the motor. A current increase check part performs check processing to check whether the current value detected by the current detection circuit has increased. A motor rotation stop part stops rotation of the motor when the current increase check part determines that the current has increased. A reverse driving part reverses the rotation direction of the motor and rotationally drives the motor after stopping of the motor by the motor rotation stop part.

Provided herein is a BLDC motor having a control system, a rotor including a motor magnet having a plurality of alternating magnetic poles thereon, a stator and a ring magnet. The ring magnet is mounted on the rotor axially adjacent the motor magnet. The number of poles on the ring magnet is an integer multiple of the number of poles on the motor magnet. Also provided is a method for controlling the BLDC motor including the steps of supplying a current to the motor, determining if the torque produced by the motor is in a positive or negative direction, determining a multiplier based on the direction of the torque, multiplying the supplied current by the multiplier, implementing a commutation sequence to provide current to the motor, measuring the current in each of the plurality of windings and adjusting the current provided to the motor based on the measured current.

A torsion bar of a torque detection device converts torque applied between an input shaft and an output shaft to a torsional displacement. A pair of yokes is secured to the output shaft, and forms a magnetic circuit in a magnetic field of a multipolar magnet secured to the input shaft. A magnetic flux guide member has a main body facing the yoke to guide magnetic flux of the magnetic circuit. A magnetic sensor is placed at an extension, and detects magnetic flux guided by the magnetic flux guide member. The magnetic flux guide member is configured to allow magnetic permeance per unit area between the magnetic flux guide member and the yoke to be greater at a location in the main body from which the extension is branched, than at a circumferential end portion of the main body.

A torsion bar of a torque detection device converts torque applied between an input shaft and an output shaft to a torsional displacement. A pair of yokes is secured to the output shaft, and forms a magnetic circuit in a magnetic field of a multipolar magnet secured to the input shaft. A magnetic flux guide member has a main body facing the yoke to guide magnetic flux of the magnetic circuit. A magnetic sensor is placed at an extension, and detects magnetic flux guided by the magnetic flux guide member. The magnetic flux guide member is configured to allow magnetic permeance per unit area between the magnetic flux guide member and the yoke to be greater at a location in the main body from which the extension is branched, than at a circumferential end portion of the main body.