Abstract: Provided is an armature structure of a three-phase motor which includes: 6N (N is a natural number) slots; 3N coils per phase; 3N main poles; and 3N auxiliary poles.

Abstract: A stator core including field slots housing field windings and armature slots housing armature windings is provided. Permanent magnets are housed in the respective armature slots. Field windings face to the permanent magnets directly or via the stator core on the outer and inner circumferential sides. A coil end of one of the armature windings straddles the predetermined one of the field slots and passes over the axial end face of each of the permanent magnets in the corresponding one of the field slots over which the coil end straddles.

Abstract: A permanent-magnet-embedded electric motor includes a stator core including a yoke and a plurality of teeth, a rotor core including a plurality of magnet insertion holes, and a plurality of permanent magnets respectively inserted into the magnet insertion holes, each being arranged with a lateral direction set in a radial direction of the rotor core and with a longitudinal direction set in a direction orthogonal to the radial direction. When a width of base sections of the teeth is represented as S1, a width of a distal end sections of the teeth is represented as S2, a width of the permanent magnets in the longitudinal direction is represented as R1, and a width of the magnet insertion holes in an extension direction thereof is represented as R2, relations of S1?R1<S2 and S1?R2?R1 are satisfied.

Abstract: A permanent magnet electrical machine has a rotor supporting a circumferential row of permanent magnets. The electrical machine further has a stator coaxial with the rotor and having a circumferential row of stator teeth carrying respective coils. The teeth provide paths for magnetic flux produced by the magnets, thereby electromagnetically linking the magnets and the coils when the rotor rotates relative to the stator. The teeth have respective core portions on which the coils are mounted, and respective tip portions located between the core portions and the rotor, neighbouring tip portions being circumferentially spaced from each other by respective gaps. Each pair of neighbouring tip portions has a bridge member and a thermal switching mechanism carried by a first tip portion of the pair.

Abstract: A motor, which can reduce a shaft current by a cheap configuration and has a high reliability, is provided. A motor which is provided between an internal combustion engine and a transmission and installed in a housing for connecting the internal combustion engine and the transmission, in which a number of magnetic poles of a rotor is “10×n” (n is a natural number), and a number of teeth of a stator is “12×n” (n is a natural number); and a rotary shaft of the rotor, bearings for supporting the rotary shaft, and the housing are composed of electric conductors; and an electric conductor circuit, which includes the rotary shaft, the bearings, and the housing and is interlinked to the stator, is formed.

Abstract: A motor pump includes a base body, a pump, and a motor. The motor includes a tubular yoke having a bottom and an opening on a base body side, a bearing, a rotation shaft, a rotor, a commutator, a brush and a brush shaft. The bearing is fitted to an inside of a bearing hole of the base body. The brush holder is fitted to an inside of the yoke and engages with an outer peripheral surface of the bearing. The brush holder and the bearing are disposed so as to be spaced from the base body in an axial direction of the rotation shaft. The motor-side seal member is provided between the yoke and the base body. The base body constitutes a stopper that prevents the brush holder from being extracted from the yoke.

Abstract: A variable speed drive (VSD) can be used to vary the voltage-to-frequency ratio (V/f) supplied to a compressor motor of a heating, ventilation, air conditioning or refrigeration (HVAC&R) system to make the motor stronger or weaker to compensate for varying conditions in the HVAC&R system. The VSD and corresponding control system or algorithm can monitor an operating parameter of the HVAC&R system, such as the kW absorbed by the motor, and then raise or lower the V/f of the VSD to obtain the lowest possible power consumption from the motor.

Abstract: A phase control circuit for a brushless motor includes a signal output unit that outputs M signals, whose phases differ from each other, in response to a change in the magnetic field resulting from the rotation of magnets placed in a rotor, and a control signal generator that generates two or more different kinds of group of phase control signals, based on at least the M signals, the group of phase control signals being used to control drive voltages, whose phases differ from each other, which are supplied to each phase of an N-phase coil (N being an integer greater than or equal to two). The control signal generator is configured such that a first phase control signal group and a second phase control signal group can be generated.

Abstract: Embodiments of the present disclosure include an actuator for steering mirrors with low magnetic hysteresis losses at high frequencies, with a fast step response, and without excessive heating of the steering mirror. Various embodiments of the actuator include two stators (a left stator and a right stator or an inner stator and an outer stator) and a rotor positioned between the stators. Each stator has a core assembly with one or more cores, two or more legs, and two or more faces positioned proximate to the rotor. The two or more legs are separated from one another by portions of the one or more coils. The rotor includes a core and a plurality of magnets, where each magnet has a face positioned proximate to the faces of one core assembly.

Abstract: An in-wheel motor includes: a motor rotor installed inside a wheel of a vehicle; and a plurality of motor stators installed on the circumference of the motor rotor so as to be separated from each other, and forming magnetic fields to rotate the motor rotor.

Abstract: A stator for an electric motor or generator comprising a circumferential support having a plurality of protrusions circumferentially distributed about the support; and a plurality of teeth arranged to receive coil windings, wherein each tooth includes a recess with interlocking means formed within the recess for engaging with a protrusion mounted on the circumferential support in a radial direction.

Abstract: A magnetic flux enhancer system for a reluctance type resolver and an electromagnetic angle sensor having the same are provided. The electromagnetic angle sensor has a stator (210) and a rotor (115) that is rotatably supported by a rotation axis on the stator and separated therefrom by a gap, the stator having at least one magnetic field generating means (220) adapted to generate a distribution of magnetic flux that extends over the gap to the rotor, and at least one magnetic field detecting means (220) adapted to detect a change in the magnetic flux distribution caused by a rotation of the rotor. The electromagnetic angle sensor comprises a magnetic flux enhancer (230) adapted to be positioned on a side of the at least one magnetic field generating means that faces the rotor and to concentrate the generated distribution of magnetic flux over the gap along a radial direction substantially perpendicular to the rotation axis.

Abstract: Sensor for continuously measuring the angular position of a shaft rotatably mounted relative to a housing. The sensor includes a stator, a rotor attachable to the shaft, and permanent magnets having alternating polarities located on a stator or a rotor capable of creating magnetic induction during the rotation of the rotor. A magnetic circuit channels the magnetic induction such that it is proportional to a sinusoidal function of the angle of the rotor. At least two electric transducers having linear output, each angularly offset one from the other relative to the stator, are located in the gaps arranged in the circuit. The magnetic circuit is toothed and includes at least one measuring unit having three teeth per pair of magnets, each tooth including a gap with a transducer.

Abstract: A rotor for a brushless motor is resistant to degradation in alternative fuels and has desirable magnetic properties. A stator for a brushless DC motor includes coils wound both clockwise and counterclockwise around teeth of a back iron. Pairs of the coils are electrically connected in parallel.

Abstract: A stator for an electrical machine, the stator including a plurality of stator teeth distributed in a non-uniform pattern with a short and long tooth spans along a circumference of the stator, wherein each stator slot between two stator teeth distanced by a long tooth span including an intermediate tooth for carrying a magnetic flux.

Abstract: The invention relates to an electrical drive having a motor with a rotor and a stationary stator, which has a coil arrangement, and having a motor controller for controlling the motor, with the motor controller being configured to pass current through the coil arrangement in order to produce an excitation field, with the coil arrangement having a plurality of coil winding sections, and with each coil winding section having a plurality of coil sections, wherein the polarity of at least one coil section of the plurality of coil sections of each coil winding section can be selectively reversed with respect to the other coil sections of the coil winding section. The drive is particularly suitable for use for an electrical tool.

Abstract: A small PMDC motor has a wound salient pole armature. The armature 22 has a winding guide 38 disposed within each winding tunnel 36 formed between adjacent salient poles of the armature. The winding guide 38 is arranged to separate the radially inner portion of the respective winding tunnel whereby windings 30 wound about the adjacent salient poles of the armature are restrained from entering into the opposite radially inner portion of the winding tunnel 36.

Abstract: An apparatus for controlling a wheel motor is provided. A plurality of switches is provided for controlling a direction of current through motor coils of the wheel motor. A brushless motor control circuit is connected to each of the plurality of switches. Responsive to a request to adjust one of an angular velocity and an angular acceleration of the wheel motor, the plurality of switches are activated to place the motor coils in a predetermined configuration to maximize torque or reduce a total back electromotive force (BEMF) from the motor coils.

Abstract: A brushless motor includes a two-phase winding stator having 4×n winding poles and auxiliary poles provided between the winding poles, and a rotor constituted by 6×n permanent magnet rotating poles having divided angle. The two-phase brushless motor can be driven by a control device for the two-phase motor which can transform electric power and rectify electronically. The two-phase brushless DC motor can increase a permeance coefficient of the rotor, improve the efficiency and the starting of the motor, and reduce torque ripple and noise thereof.

Abstract: The brushless motor has a first and second drive member. The first drive member is equipped with M phase coil groups each having N electromagnetic coils where M is an integer of 1 or greater and N is an integer of 1 or greater. The second drive member has a plurality of permanent magnets, and is able to move relative to the first drive member. The first drive member has 2 (M×N) magnetic body cores. Each phase electromagnetic coil is coiled on a periodically selected magnetic body core at a ratio of 1 to 2M from among the arrangement of 2 (M×N) magnetic body cores.

Abstract: The present invention relates to a two-phase brushless DC motor which can increase a pemerance coefficient of a rotor to the maximum to thereby improve efficiency and starting feature of the motor, and to reduce torque ripple and noise thereof. The brushless motor of the present invention includes a two-phase winding stator having 4×n winding poles and auxiliary poles provided between the winding poles, and a rotor constituted by 6×n permanent magnet rotating poles having divided angle. Auxiliary poles between the stator poles can be provided. The two-phase brushless motor of the present invention can be driven by a control device for the two-phase motor which can transform electric power and rectify electronically.

Abstract: A magnet comprising grains of a ferromagnetic material whose main component is iron and a fluorine compound layer or an oxy-fluorine compound layer of fluoride compound particles of alkali metals, alkaline earth metals and rare earth elements, present on the surface of the ferromagnetic material grains, wherein an amount of iron atoms in the fluorine compound particles is 1 to 50 atomic %.

Abstract: A dynamoelectric machine comprising a stator having a plurality of slots and teeth, armature windings wound around the teeth, and a rotor disposed inside the stator, wherein an alloy member is disposed in the inner periphery of the stator and the magnetic compensator has its surface or inside thereof a high resistance layer.

Abstract: The present invention provides an electricity generator for a lighting tower having a plurality of discharge lamps, each lamp being of power greater than 750 W, the generator being arranged to be driven by an engine, the generator being a multiphase generator having n phases, where n is an even integer, each phase being independent in a magnetic circuit that is common to all of the phases and being configured to power one lamp, the generator comprising a rotor with permanent magnets, having 3 n poles, and a stator concentric with the rotor and subjected to the radial magnetic flux from the magnets, the stator comprising a stack of laminations of silicon iron having a silicon content greater than 0.5% and of individual thickness greater than 0.35 mm, defining 4 n magnetic circuit teeth, with every other tooth carrying a winding.

Abstract: The present invention is intended to provide a winding arrangement of single star connection for a rotating electrical machine, capable of enhancing insulation performance in coils of the same phase. In such winding arrangement, a first coil U1 to a sixth coil U6 are formed respectively in coil arranging parts 1U to 6U. Next, a coil arranging part 7U is skipped and the seventh coil U7 is formed in a coil arranging part 8U. Then, a coil formed at the end of winding (eighth coil U8) is formed in the skipped coil arranging part 7U.

Abstract: A motor having a structure configured to reduce magnetic resistance between a rotor and a stator, a method for manufacturing the motor, and a washing machine using the motor are disclosed. The motor includes a rotor, and a stator co-operating with the rotor. The stator includes a main core and an auxiliary core. The main core includes a base and a plurality of teeth protruding from the base. The auxiliary core is structured to prevent the occurrence of magnetic resistance from being generated from spaces, defined between adjacent teeth, when the stator co-operates with the rotor.

Abstract: A rotor for a brushless motor is resistant to degradation in alternative fuels and has desirable magnetic properties. A stator for a brushless DC motor includes coils wound both clockwise and counterclockwise around teeth of a back iron. Pairs of the coils are electrically connected in parallel.

Abstract: A stator structure of a motor. The stator structure has a base including a main body and a plurality of protrusions extending from the main body. A stator part has a plurality of magnetic-pole portions, wherein each protrusion is positioned in a gap between every two adjacent magnetic-pole portions when the stator part is disposed on the base, and a coil wound around the stator part. The outer circumference of the main body of the base includes a plurality of circular arcs with different radii, so as to provide a function of attaining bias when the motor is driven to start and preventing reduced rotational efficiency of the motor.

Abstract: An inductor-type resolver capable of reducing a residual voltage by providing a correction winding inside the resolver is provided. Two magnetic pole portions 11 and 15 include winding portions W11 and W12, respectively, which constitute a first signal detecting winding W1. Two magnetic pole portions 13 and 17 include winding portions W21 and W23, respectively, which constitute a second signal detecting winding W2. A remaining magnetic pole portion W19 includes a correction winding W3 for obtaining a correction voltage used for reducing the residual voltage.

Abstract: A brushless electric motor system comprises a rotor and a stator comprising poles. Electrical phase windings have coils (U1-6, V1-6, W1-6) wound around the poles. Power switches (T1-24) controlled by a control device supply electric current the windings from positive and negative rails connected to power supply. For each phase at least one group of four power switches arranged in a H-bridge configuration is provided. The coils of each phase winding are preferably divided into winding group (U1-3, Ua-6, V1-3, V4-6, W1-3, W4-6) and the electric conductor of each winding group is then electrically conductor of the other winding groups. Then four power switches arranged in an H-configuration is provided for each winding group. The use of power switches in H-bridge configurations allows the faulty windings or winding groups to be disabled and that the rest of the windings or coils can be used for driving the rotor, this giving the motor system a high reliability.

Abstract: An electrical motor or generator comprises a rotor 79 without windings, a stator 78 having armature windings comprising at least two coils A1, A2 having active portions positioned within armature winding slots 81 in a stator iron, and field windings F having active portions positioned within field winding slots 80 in the stator iron. An electronic control circuit is provided for controlling the currents in the coils A1, A2 in synchronism with rotation of the rotor such that periods in which a magnetomotive force is generated in one direction by current flow in one of the coils alternate with periods in which a magnetomotive force is generated in the opposite direction by current flow in another of the coils. The armature winding slots and the field winding slots are equal in number and alternate with one another in the stator iron.

Abstract: An electric motor with a stator structure having a high thermal conductivity from coils to a stator core, and capable of suppressing vibration of coils and adjusting an output torque and a cogging amount of the motor. A stator core is provided at its inner periphery with main teeth extending radially and spaced at regular intervals from one another. Auxiliary teeth are provided in slots formed between adjacent main teeth. Coils are arranged such that, when wound around the main teeth, their outer peripheral faces are in close contact with the auxiliary teeth. Since the coils are in contact at their central portions with the main teeth and in close contact at their outer peripheral portions with the auxiliary teeth, heat generated from the coils energized is efficiently conducted to the stator core, and removed by cooling devices provided at outer peripheral portions of the stator, thereby cooling the motor. Since the coils are fixedly held between the main and auxiliary teeth, vibration can be prevented.

Abstract: A series-wound motor is disclosed which is particularly suitable as a universal motor for an electric power tool. The motor comprises a stator with at least two field poles, each having two pole horns. At least one of the pole horns of each pole comprises first and second protrusions extending circumferentially from an axial edge of the pole horn. Sparking is reduced thereby. Also a retarded motor is disclosed, wherein each pole comprises a pole horn having a run-on edge, and further comprises a pole horn having a run-off edge. The pole horns having run-off edges are shortened in circumferential direction compared to the pole horns having run-on edges or comprise at least one cutout section extending in circumferential direction. The motor can be switched between a motor operation and a brake operation, without the need for providing commutating windings or additional coils to avoid excessive sparking.

Abstract: A superconducting PM machine has a stator, a rotor and a stationary excitation source without the need of a ferromagnetic frame which is cryogenically cooled for operation in the superconducting state. PM material is placed between poles on the rotor to prevent leakage or diffusion of secondary flux before reaching the main air gap, or to divert PM flux where it is desired to weaken flux in the main air gap. The PM material provides hop-along capability for the machine in the event of a fault condition.

Abstract: An electric power steering system for a vehicle includes a steering wheel and a steering shaft that is connected to the steering wheel. A worm gear is connected to the steering shaft. A worm is threadably engaged to the worm gear. A permanent magnet motor is connected to the worm. The permanent magnet motor includes a stator with twelve slots and a rotor with ten poles. The rotor includes one or more axial rotor sections. If more than one axial rotor section is employed, the axial rotor sections are rotationally offset. The axial rotor sections are rotationally offset by an offset angle that is equal to a cogging angle divided by the number of axial rotor sections. The rotor includes breadloaf, spoke, radial or arc permanent magnets.

Abstract: A brushless electric machine (30) having a stator (31) and a rotor (32) and a main air gap (34), the rotor (32) having pairs of rotor pole portions (22b, 22c, 32f, 32l) disposed at least partly around the axis of rotation (32p) and facing the main air gap (24b, 24c, 34), at least one stationary winding (20b, 20c, 33b) separated from the rotor (22b, 22c, 32) by a secondary air gap (23b, 23c, 35) so as to induce a rotor-side flux in the rotor (22b, 22c, 32) which controls a resultant flux in the main air gap (24b, 24c, 34). PM material (27b, 27c) is disposed in spaces between the rotor pole portions (22b, 22c, 32f, 32l) to inhibit the rotor-side flux from leaking from said pole portions (22b, 22c, 32f, 32l) prior to reaching the main air gap (24b, 24c, 34). By selecting the direction of current in the stationary winding (20b, 20c, 33b) both flux enhancement and flux weakening are provided for the main air gap (24b, 24c, 34).

Abstract: A stator comprises plural stacked silicon steel plates having aligned axle holes. An auxiliary plate is superimposed on the stacked silicon steel plates and comprises an axle hole aligned with the axle holes of the silicon steel plates. Each silicon steel plate comprises even-numbered radial arms each having a magnetic pole face at a distal end thereof. The auxiliary plate comprises auxiliary radial arms, wherein the auxiliary radial arms and the radial arms of the silicon steel plates are alternately disposed. Form on a distal end of each auxiliary radial arm is a magnetic pole face that extends vertically, the magnetic pole face being appropriately spaced from the magnetic pole faces of the radial arms of the silicon steel plates. The magnetic pole faces of the auxiliary radial arms of the auxiliary plate and the magnetic pole faces of the silicon steel plates have different widths or thicknesses.

Abstract: An electro magnetic rotating machine comprising at least a rotor having at least one magnet creating rotor magnetic poles; and at least one pair of axially spaced apart solenoids disposed on opposite sides of the rotor magnetic poles, the axis of each solenoid is arranged to be transverse a radius of the path of rotation of the rotor. The solenoids are configured to minimize overlapping of magnetic flux between at least one of the rotor magnetic poles and one of the solenoids when said magnetic pole is adjacent to said solenoid.

Abstract: A brushless motor is composed of a stator for generating a rotating magnetic field by supplying three-phase alternating current consisting of U, V and W-phases thereto and a rotor having plural poles and rotatably disposed inside the stator. The rotor is rotated by the rotating magnetic field generated in the stator. The stator includes core teeth on which coils are wound. A tooth-group consisting of a center tooth and two side teeth is allocated to each phase, and excitation current in one phase is simultaneously supplied to three coils wound on the three teeth in the same tooth-group. The center teeth of each phase are positioned with equal intervals therebetween, while the side teeth are positioned so that they substantially coincide with the centers of the rotor poles when a center tooth in the same tooth-group coincides with the center of one of the rotor poles.

Abstract: An apparatus for stabilizing the spin axis of a rotating system, the rotating system having a rotor and motor means to cause rotation of the rotor about the spin axis and a magnet, windings, a source of drive current and an actuator combined with the motor means and forming a source of actuator current energizing the windings to generate a radial force which stabilizes the position of the spin axis and dampens other than rotational movements of the rotor.

Abstract: A low inductance electrical machine that may be used as an alternator or motor with low armature inductance is disclosed. Arrangements of complementary armature windings are presented in which the fluxes induced by currents in the armature windings effectively cancel leading to low magnetic energy storage within the machine. This leads to low net flux levels, low core losses, low inductance and reduced tendency toward magnetic saturation. The inclusion of additional gaps in the magnetic circuit allows for independent adjustment of air gap geometry and armature inductance. Separately excited field arrangements are disclosed that allow rotor motion to effect brush-less alternator or brush-less motor operation. An exemplary geometry includes a stator including two annular rings and a concentric field coil together with a rotor structure separated from the stator by four air gaps.

Abstract: A low inductance electrical machine which may be used as an alternator or motor with low armature inductance is disclosed. Arrangements of complementary armature windings are presented in which the fluxes induced by currents in the armature windings effectively cancel leading to low magnetic energy storage within the machine. This leads to low net flux levels, low core losses, low inductance and reduced tendency toward magnetic saturation. Separately excited field arrangements are disclosed that allow rotor motion to effect brushless alternator or brushless motor operation. An exemplary geometry includes a stator including two toroidal rings and a concentric field coil together with a rotor structure separated from the stator by four air gaps. An alternate embodiment allows for counter-rotation of two rotor elements for use as a flywheel energy storage system in which the external gyroscopic effects cancel.

Abstract: A discharge lamp lighting device driven by an internal combustion engine is disclosed which is capable of lighting a discharge lamp without using a ballast constituted by a leakage transformer. The device includes a generator which is driven by the internal combustion engine and of which output characteristics exhibit drooping characteristics, so that an output voltage of the generator may be applied to a discharge lamp without using any ballast. Output characteristics of the generator are so set that an output voltage of the generator at a non-load state thereof may be higher than a break-down voltage of the discharge lamp, a short-circuit current of the generator may have a level sufficient to restrict a discharge current of the discharge lamp just after starting of discharge thereof to an allowable level or below, and a voltage across the discharge lamp and a discharge current thereof at a steady state thereof each are kept within a rated range.

Abstract: This invention is to provide a low-cost structure that a cogging torque and a torque ripple are small and a stable rotation is provided in a radial gap type motor.A portion that stator pole teeth 37 to become interpoles are provided between stator poles 38 and a plurality of stator pole teeth 37 are not continuously provided between the partial stator poles 38 is provided. As a result, in this invention, a magnetic attraction force between the stator pole teeth 38 and the rotating pole 9 of a rotor 6 is stronger in the case that the pole teeth 37 are provided than in the case that the pole teeth 37 are not provided.Accordingly, the rotational shaft 12 of the rotor 6 is supported at three points of points P, Q and R of the bearing cylinder 4, and a rotary force is received at the point P as a center. As a consequence, the rotational shaft 12 is rotated with less contact friction with the bearing cylinder 4.

Abstract: A hybrid single-phase variable reluctance motor system has a stator (1) having a pair of oppositely disposed salient main poles (4) provided with main windings (12) and at least one pair of oppositely disposed salient auxiliary poles (5, 6) provided with auxiliary windings (13, 14) and disposed intermediate the main poles (4) on the stator (1). Furthermore the motor system has a rotor (2) having a pair of oppositely disposed salient poles (7) without windings. Additionally the motor system includes a control circuit (11) for rotating the rotor (2) during normal running by supplying current pulses to the main stator windings (12) in synchronism with rotation of the rotor (2) and for rotating the rotor (2) on starting by supplying current pulses to both the main and auxiliary stator windings (12, 13, 14) in synchronism with rotation of the rotor (2).

Abstract: A brushless DC motor comprises a rotor (20) and a stator (22) having confronting surfaces. Permanent magnets (M) are provided at one of the confronting surfaces, the magnets being equally angularly spaced around an axis (A--A) of rotation of the rotor such that each magnet occupies part of a respective pole arc (PA) of a first circle (C1) centred on the axis (A--A), the pole arcs each subtending a common pole angle .alpha. to the axis. Teeth (Tm) are provided at the other of the confronting surfaces, the teeth being angularly spaced from one another around the axis (A--A) such that each tooth occupies part of a respective tooth arc (TA) of a second circle (C2) centred on the axis, the tooth arcs each subtending a common tooth angle .beta. to the axis. Windings (40) are wound around the teeth (Tm) whereby energisation of the windings with electrical currents at respective phases will produce a torque that will rotate the rotor (20). The tooth angle .beta. is substantially equal to the pole angle .alpha..

Abstract: A three-phase brushless dc motor includes a permanent-magnet rotor magnet arrangement having at least four poles and a Y-connected, or star-connected, three-phase stator winding. The winding's phases are arranged non-overlapping in slots of a slotted stator, the currents flowing in the three phases being controlled via at least three semiconductor elements by at least three magnetic-field-sensitive rotor position sensors. Each sensor is associated with a respective two of the winding's three phases and triggers a commutation which switches off the current in one of the associated two phases and switches on the current in the other of the associated two phases. The sensors are located to sense the permanent-magnet flux emanating from the rotor poles themselves. The rotor position sensors are provided at special angular locations on the stator.

Abstract: Electric machine in which parts subject to magnetostrictive forces are sized and configured in a particular manner. Such parts (1) have radial dimensions that vary along the axial direction. The pads are formed by laminations (12) that are assembled in an alternated arrangement, either individually or by groups, and have differing inner and/or outer dimensions and/or shapes. Such a solution is instrumental in reducing the noise caused by vibrations brought about by the electromagnetic forces generated by the machine.

Abstract: A DC brushless motor 3 is provided which comprises armature 31 and rotor 32. Rotor 32 is provided with a rotor yoke that has four main poles 321 on its periphery. Slots with a radial-direction size of L.sub.m are formed on main poles 321 of the rotor yoke. Magnetic-field permanent magnet 323 with an approximate thickness of L.sub.m is embedded in each slot 322, such that the radial-direction size L.sub.m of slot 322 and the air gap length L.sub.g of the air gap formed between rotor 32 and armature 31 satisfy the relationship 0<L.sub.m +L.sub.g .ltoreq.2 mm.

Abstract: A three-phase brushless dc motor includes a permanent-magnet rotor magnet arrangement having at least four poles and a Y-connected, or star-connected, three-phase stator winding. The winding's phases are arranged non-overlapping in slots of a slotted stator, the currents flowing in the three phases being controlled via at least three semiconductor elements by at least three magnetic-field-sensitive rotor position sensors. Each sensor is associated with a respective two of the winding's three phases and triggers a commutation which switches off the current in one of the associated two phases and switches on the current in the other of the associated two phases. The sensors are located to sense the permanent-magnet flux emanating from the rotor poles themselves. The rotor position sensors are provided at special angular locations on the stator.