Abstract: A stator for a rotary electric machine, having a stator mass that has slots in which electrical conductors introduced axially into the slots are housed, each of the slots having a continuously closed contour.

Abstract: 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.

Abstract: The rotor with a non-through shaft for a rotary electric machine comprises a cylindrical magnetic body clamped between two half-shafts, each comprising an attachment flange connected to the magnetic body, axial housings being uniformly provided in the magnetic body on at least one diameter of the magnetic body in order to house conductive bars. At least one attachment flange comprises insertion holes, each arranged facing a housing for inserting the conductive bars into the housings and the exterior diameter of the attachment flange is substantially equal to the exterior diameter of the magnetic body, the attachment flange comprising as many insertion holes as housings.

Abstract: A stator for an electric machine provided for purely electrically driving a motor vehicle is provided with a stator body forming stator grooves, a stator winding through which current can flow, which engages in the respective stator groove and axially protrudes from the stator groove, for forming an electromagnetic rotating field and an insulation paper, which is provided in the stator groove between the stator winding and the stator body, for electrically insulating the stator winding from the stator body, wherein the insulation paper protrudes from the stator groove, wherein the insulation paper is provided with an additional layer on the surface thereof for providing a higher creepage resistance compared to the surface of the insulation paper without the additional layer.

Abstract: A rotor core of a rotating electrical machine has interpole bridges each disposed on an outer circumferential side with respect to a permanent magnet in a non-magnetic portion between the poles, and interpole diameter bridges each surrounded by two permanent magnets and an interpole bridge. The outer circumferential surface of each interpole bridge is formed by a first flat surface. Thus, a path of a magnetic flux passing through a magnetic gap is lengthened, so that a q-axis inductance is reduced. In addition, a width in a radial direction of each interpole bridge and a width in a circumferential direction of each interpole diameter bridge are constant, and each interpole bridge and each interpole diameter bridge are disposed so as to be perpendicular to each other to form a T shape. Thus, the concentration of stress during press-fitting of the permanent magnet into a magnet hole can be reduced.

Abstract: An electric machine may include an stator and a rotatable rotor. At least one of the stator or the rotor may include a plurality of multi-part trapezoidal teeth with an electromagnetic coil disposed around each tooth.

Abstract: To solve the problem of large electromagnetic noise in AC traction motor, embodiments have open square notches at symmetrical positions on both sides of stator teeth of AC traction motor to effectively reduce electromagnetic noise without affecting other performance indicators of motor. In addition, embodiments fit the functional relationship between the optimal notch size or optimal slotting position size of motors and their power by determining the optimal notch size or optimal slotting position size of motors with different power grades, so as to achieve the noise reduction effect.

Abstract: A laminated core for a rotor and/or a stator of a rotating electric machine includes teeth arranged adjacent to one another in a peripheral direction of the laminated core and delimiting slots for accommodating an electrical conductor that forms a winding. A cover unit is arranged on a side of an air gap between the rotor and the stator and delimits the slots in the radial direction. The cover unit has in a region of a respective one of the slots at least two tapering regions which are spaced apart from one another in the peripheral direction of the laminated core, with a material of the cover unit being thinner in the tapering regions in a radial direction of the laminated core than in a region of the cover unit adjoining the tapering regions.

Abstract: A stator for a rotary electric machine includes a stator core and a stator winding. The stator core has a hollow cylindrical shape and includes slots. The stator winding includes segment conductors held in the slots. The slots extending outward in a radial direction from an inner peripheral surface of the stator core. The slots include first and second slots. The second slot is shallower than the first slot. The segment conductors include a segment conductor including a first rectilinear portion held in the first slot, a second rectilinear portion held in the second slot, and a coupler coupling the first rectilinear portion and the second rectilinear portion to each other. The first rectilinear portion and the second rectilinear portion protrude from an end surface of the stator core.

Abstract: An electric motor comprises a stator presenting a first surface. A rotor is rotatable relative to the stator. The rotor presents a rotor raceway disposed in spaced relationship with the first surface of the stator. The first surface of the stator defines a plurality of slots in spaced relationship with one another to define a plurality of spaced teeth between the slots. At least one electrical conductor is disposed in each of the slots and configured to selectively create a moving magnetic field for acting upon the rotor for providing rotational movement of the rotor. A portion of the at least one electrical conductor extends substantially into radial alignment with, or past the first surface of the stator to at least partially define a stator raceway of the stator for engaging the rotor raceway of the rotor during relative radial movement between the rotor and the stator.

Abstract: An interior permanent magnet machine is described. The machine includes a rotor rotatable about a central machine axis. The rotor includes a plurality of permanent magnet openings and a plurality of permanent magnets disposed therein. The permanent magnet openings are separated by rotor webs configured to facilitate reducing leakage flux through the rotor webs. The machine also includes a stator disposed coaxially with the rotor and separated from the rotor by a circumferential air gap. The stator includes a plurality of stator teeth that define a plurality of stator slots therebetween. The stator teeth include a stator tooth tip configured to facilitate reducing cogging torque and torque ripple.

Abstract: A lamination for use in an electric machine stator includes a body having a generally circular outer periphery and a generally circular inner periphery, spaced from the outer periphery and a plurality of spaced apart teeth extending inwardly from the circular inner periphery. Each of said teeth define opposed inner edges thereof. The lamination includes a first pair of tips extending tangentially in opposed directions from the inner edge of one of said teeth and a second pair of tips extending tangentially in opposed directions from the inner edges of another one of said teeth. A tip of the first pair of tips and a tip of the second pair of tips define a first configuration having a first gap therebetween and defining a second configuration having a second gap therebetween. The first gap being substantially less than the second gap.

Abstract: A coil is a coil of a conductive wire that has a quadrangular cross section, that is spirally wound and laminated to have a series of turns including first to n-th turns (n is an integer of 3 or more), and that is provided, on at least some of the first to n-th turns in the coil, with deformed portions representing recesses each having a shape different from a shape of another portion of the conductive wire. In each of the first and n-th turns respectively lying at both ends of the series of turns, an outer surface lying on a side opposite to a center of the series of turns extends flush along with a plane intersecting the series of turns.

Abstract: A method of manufacturing an armature coil includes the steps of: stacking multiple armature coils to generate a stack of armature coils in a stacking direction as a first step; securing first and second ends of the stack of armature coils with a pair of clamping dies, respectively, as a second step after completing the first step; and sandwiching and depressing the stack of armature coils with pressing die in a given direction intersecting the stacking direction as a third step after completing the second step. The pressing die includes a pair of sandwiching dies to sandwich and depress the stack of armature coils in the given direction. The pair of sandwiching dies has a narrower interval at a position closer to a first end of the stack than that at another position closer to a second end thereof.

Abstract: An EC motor for an electric hand tool having a stator in which a rotor is rotatably mounted, which comprises a rotor lamination stack, which has a passage opening and is formed of individual laminations, and a rotor shaft which is cast in the passage opening of the rotor lamination stack by means of a casting compound, and having a plurality of permanent magnets, which are received in the pockets formed in the rotor lamination stack. An annular channel, which is connected to the pockets in a fluid-conducting manner via radial channels, each of which is formed of a plurality of channel sections formed in adjacent laminations of the rotor lamination stack, is formed between the rotor shaft and the wall of the passage opening for supplying the casting compound from the annular channel to the pockets. A method is also provided for producing a rotor for an EC motor.

Abstract: Provided is a stator segment for the stator or the rotor of an electrical machine including a segment body circumferentially extending about a longitudinal axis of the stator segment between two circumferential ends. The segment body includes: a plurality of teeth protruding according to a radial direction orthogonal to the longitudinal axis, each tooth circumferentially extending between two respective side faces, the teeth being circumferentially distributed between two end teeth of the teeth, the teeth including at least one intermediate tooth circumferentially included between the end teeth, a plurality of slots, the plurality of slots including a plurality of intermediate slots circumferentially included between the two end slots, wherein side faces of the two end teeth are inclined with or parallel to each other and the side faces of the at least one intermediate tooth are respectively parallel to each other or inclined with respect to each other.

Abstract: A brushless motor includes a stator (26) having six slots (30), and a rotor having two poles. The rotor is adapted to rotate with respect to the stator. By adopting a 6-slots-2-poles structure, the brushless motor effectively reduces operational noise due to iron loss and unbalanced pull. As a result, the working life of the motor can be improved.

Abstract: A stator comprises multiple, stacked laminations, which collectively define a core having a number of posts arranged circumferentially about the core. Each post extends into two prongs defining a first slot between the prongs. The spacing between each posts and its two prongs defines a second slot having a radially inner and outer slot. The outer slot geometry has an increasing width extending radially outward from the radially inner end, and transitioning to a decreasing width extending to the radially outer end.

Abstract: A stator is assembled by stacking, in the axial direction, a plurality of magnetic steel sheets having tooth portions. The steel sheets include connected tooth steel sheets in which the inner-circumferential-side end portions of the tooth portions are connected via connection portions in an annular shape along the circumferential direction, and non-connected tooth steel sheets which are separated from each other with the tooth portions not connected to each other. The connected tooth steel sheets and the non-connected tooth steel sheets are joined to each other in the axial direction via swage portions provided in the tooth portions. The thickness of each connection portion is smaller than the thickness of the other part of each steel sheet.

Abstract: An armature core is configured by arranging into an annular shape: at least one first core segment that includes: a first core back portion; a first tooth portion; and a mounting portion that is formed on an outer circumferential portion of the first core back portion; and a plurality of second core segments that include: a second core back portion; and a second tooth portion; the mounting portion includes projecting portions that project on two circumferential sides from the first core back portion; and the first core segments and the second core segments that are adjacent to each other are fixed in a state in which facing side surfaces between the first core back portions and the second core back portions contact each other, and inner circumferential surfaces of the projecting portions and outer circumferential surfaces of the second core back portions are in contact.

Abstract: A brushless motor includes: a stator core having a cylindrical yoke portion and a teeth portion having a shape protruding from an inner circumferential surface of the yoke portion; and a rotor that is disposed inside the stator core, spaced apart from the teeth portion, and uses a center axis of the yoke portion as an axis of rotation. The yoke portion includes, on its outer circumferential surface, a notch portion at a position on the back side of the teeth portion. The notch portion has a circumferential width smaller than a circumferential width of the teeth portion.

Abstract: A core segment linked body when opened out rectilinearly is configured: such that a distance between adjacent width reduced portions is greater than a width dimension of width expanded portions when adjacent core segments are in an expanded position, and the distance between the adjacent width reduced portions is less than the width dimension of the width expanded portions when the adjacent core segments are in a contracted position; and so as to satisfy (te?tn)/?s?>0, and 0<(te?tn)/te?0.27, where ?s? is a distance between center lines of the adjacent magnetic pole teeth in the expanded position, te is a width dimension of tooth main portions, and tn is the width dimension of the width reduced portions.

Abstract: In an armature coil according to the present invention and, more particularly, in an armature coil including a plurality of coil conductors wound around a plurality of slots which are formed in a stator core and opened on the radially inner side, the circumferential width of the plurality of the coil conductors is formed in a substantially trapezoidal shape which gets narrower toward the radially inner side and the cross-sectional areas of the plurality of the coil conductors in the slot are each substantially the same and the circumferential width thereof is formed narrower as the coil conductor is arranged toward the radially inner side; and one coil conductor is formed in a convex shape and another coil conductor is formed in a concave shape along the convex shape.

Abstract: A tubular body for an electrical machine is provided. The tubular body comprises a curved surface area, a first tooth and a second tooth. The tubular body is arrangable with respect to a further tubular body such that one of the tubular body or the further tubular body is rotatable with respect to the other one around a rotary axis. The first tooth and the second tooth extend from the curved surface area along a radial direction with respect to the rotary axis. The first tooth comprises a first side wall facing a second side wall of the second tooth, wherein the first side wall comprises a first section which is parallel to the second side wall such that a circumferential distance between the first section and the second side wall is constant along the radial direction.

Abstract: A tooth of a stator has a tapered shape in which a tooth width decreases toward a distal end portion thereof. A winding is formed of an edgewise winding wound around the tooth in a row. The winding is supplied with power so that a terminal on a base portion side of the tooth may have a higher voltage than that of a terminal on the distal end portion side thereof. A tooth width Th of the base portion is set within the range of Tmin<Th<1.25Tha defined by a tooth width Tha that maximizes an index using an outer radius and a core back width of a stator core, a clearance of the windings in the slot, a winding width, an air gap between the teeth and the winding, a pitch of the slot, and an inclination angle of the winding, and a permissible lower limit Tmin.

Abstract: Provided is a permanent magnet type motor including: a rotor including a rotor core and a plurality of permanent magnets; a conducting circuit including a first electric conductor extending in an axial direction of the rotor and being disposed between permanent magnets in a circumferential direction of the rotor and a second electric conductor for connecting the first electric conductors electrically; and a stator disposed so as to be opposed to the rotor, including a stator core and an armature winding. A rotation angle is detected by measuring current flowing in the armature winding. The stator core is formed to have a shape in which, a slot pitch is defined by ?s=(2×?×Rs)/Ns, where an inner radius of the stator is represented by Rs and a number of slots is represented by Ns, a value Wsn obtained by dividing a slot opening width Ws by the slot pitch ?s satisfies “0.08?Wsn”.

Abstract: Obtain a rotary electric machine by which a share of coil slots for a stator winding in slots, which are formed in a stator core, can be increased, and heat generation at a central portion of a stator can be decreased. The stator winding is composed of coil slots, which are inserted to the slots, and coil ends extended toward the outside in the axis direction of the stator core; and the coil conductors of the coil slots are configured in such a way that cross-sectional areas at central portions in the axis direction are wider cross-sectional areas at both end portions, and the cross-sectional areas of the coil conductors are reduced along the coil slots from the central portions to the both end portions.

Abstract: A three dimensional soft magnetic metal mass suitable for milling is formed wrapping soft magnetic metal ribbon into a three dimensional shape and then applying adhesive to the three dimensional shape. The adhesive permeates the three dimensional shape. The adhesive is then cured. If the soft magnetic metal mass is made as a toroid, then it could be processed into an electromechanical component. The electro-mechanical component would then be suitable for use in very high frequency electric motors.

Abstract: A three-phase electromagnetic motor includes: a stator that is formed by winding a winding around a magnetic pole formed between slots of a stator core; and a rotor that is disposed inside the stator and has a permanent magnet. The three-phase electromagnetic motor is formed of 8n poles and 6n slots (n is a natural number). 3n windings are wound around every other magnetic pole among a plurality of magnetic poles of the stator core.

Abstract: A wind turbine rotary electric machine having a tubular body, in turn having a cylindrical wall; and a plurality of clips formed integrally with the cylindrical wall and configured so that each pair of facing clips defines a seat for housing an active sector.

Abstract: An armature for a rotating electric machine includes an armature core and an armature coil. The armature core includes a substantially annular main body disposed in radial opposition to a field of the machine and teeth extending from the main body radially toward the field. The armature coil is arranged between the teeth of the armature core. For each of the teeth, there are formed a protrusion and a pair of claws at a distal end of the tooth. The protrusion protrudes from a circumferentially central part of the distal end of the tooth radially toward the field. The claws extend, respectively on opposite circumferential sides of the protrusion, from the distal end of the tooth toward the field. Each of the claws has a smaller width at its distal end than at its proximal end and is arcuate-shaped so as to engage with and thereby retain the armature coil.

Abstract: A cogging torque can be significantly reduced in a three-phase permanent magnet-type synchronous motor. In a three-phase permanent magnet-type synchronous motor where a fraction of 2N/3P is not an integer assuming the number of magnetic poles of a rotator is P and the number of slots of a stator is N, the stator includes a tooth facing a surface of a magnetic pole of the rotator via a void and a tooth width of the tooth in the circumferential direction is approximately ½ of a slot pitch of the stator. In a three-phase permanent magnet-type synchronous motor of an outer rotor type, the tooth of the stator has a radial cross section with an approximately uniform shape from a tooth tip portion to a tooth root portion or a radial cross section with a larger tooth root portion than a tooth tip portion to allow mounting a winding unit from the tooth tip portion. The winding unit is preliminarily wound by a coil.

Abstract: A method of manufacturing a stator assembly for an electrical machine, including the steps of: arranging a plurality of elongate wire segments in single file along the depth of a stator slot located between opposing walls of a pair of adjacent stator core teeth; compressing the wire segments substantially in a direction of the stator slot depth, whereby the wire segments are compacted into the stator slot; plastically deforming at least one of the wire segments, whereby a cross-section of the plastically deformed wire segment is expanded in a direction along which the opposing tooth walls are spaced from each other; and deforming the tip of at least one of the pair of adjacent stator core teeth to at least partially close up the stator slot upon the compressed wire segments and further compacting the wire segments into the stator slot.

Abstract: A tubular body for an electrical machine is provided. The tubular body comprises a curved surface area, a first tooth and a second tooth. The tubular body is arrangable with respect to a further tubular body such that one of the tubular body or the further tubular body is rotatable with respect to the other one around a rotary axis. The first tooth and the second tooth extend from the curved surface area along a radial direction with respect to the rotary axis, wherein the first tooth and the second tooth are spaced apart from each other along a circumferential direction around the rotary axis. The first tooth comprises a first side wall facing a second side wall of the second tooth, wherein the first side wall comprises a first section which is parallel to the second side wall such that a circumferential distance between the first section and the second side wall is constant along the radial direction.

Abstract: An armature core of a stator has an annular portion and a plurality of teeth extending radially from the annular portion. A segment coil is configured by electrically connecting a plurality of segment conductors together. The segment conductors extend axially through slots S, each of which is defined between each adjacent pair of the teeth. Each of the teeth has a width adjustment portion for decreasing a slot width in a direction perpendicular to a radial direction in the radially inward direction.

Abstract: A rotating electrical machine includes a rotor and a stator. A permanent magnet is attached to the rotor. The stator opposes the rotor with a gap provided therebetween, and has an open slot that opens toward the rotor and in which a high-voltage wire is installed. The gap has a gap length at which the sum of losses including a surface loss that occur when the high-voltage wire is excited and the rotor is rotated at a high rotation speed is less than or equal to a threshold that corresponds to a target loss.

Abstract: A method of inserting a continuous conductor having a rectangular cross-section into slot segments formed in a stator core includes forming a core member having a plurality of slot segments each having an opening and inserting a stator winding having a plurality of phases into select ones of the slot segments. Each of the plurality of phases has at least one conductor including a plurality of substantially straight segments alternately connected by a plurality of end loop segments. A section of the at least one conductor includes three consecutive end loop segments and three consecutive straight segments formed from a single continuous conductor. The method further includes narrowing the opening of each of the plurality of slot segments by forming an annular stator core having a central axis. The three consecutive straight segments are substantially similarly radially spaced from the central axis.

Abstract: A rotating electrical machine includes a stator having a stator core having a plurality of slots formed therein and a plurality of stator coils to be accommodated in the respective slots, and a rotor arranged on an inner peripheral side of the stator. The plurality of slots include a first slot and a second slot, and when a first ratio between the number of coils having the same phase to be accommodated within the first slot and the number of the plurality of coils exceeds a predetermined ratio, and a second ratio between the number of coils having the same phase to be accommodated in the second slot and the number of the plurality of coils is the predetermined ratio or lower, a width of a first slot opening that the first slot has so as to face the rotor side is 0 or wider, and is smaller than a width of a second slot opening that the second slot has so as to face the rotor side.

Abstract: A stator of a motor comprises a stator core including a plurality of plate members stacked together; the stator core including: a yoke of a tubular shape; and teeth each of which includes an extending portion extending inward in a radial direction of the yoke from the yoke and an increased-width portion formed at a tip end of the extending portion so as to have a greater width than the extending portion in a circumferential direction of the yoke; wherein the extending portion has a constant-width portion extending radially in a straight-line shape so as to have a constant circumferential width, a narrower portion having a circumferential width smaller than a circumferential width of the constant-width portion, and a clamp portion for securing the plurality of plate members to each other; and wherein at least a portion of the clamp portion is located in the narrower portion.

Abstract: The invention relates to a synchronous machine with hybridenergisation, in particular a generator for supplying the electrical system of a motor vehicle, comprising a laminated stator (16) with a multiphase stator winding (18) and a laminated rotor (20) with an energizer winding (29), which together with permanent magnets (24,25) around the rotor periphery, provides the energisation for the machine. According to the invention, favorable electrical and magnetic properties and an improvement in manufacturing conditions of the machine can be achieved, wherein the grooves (40) for the energiser windings (29) are disproportionately enlarged in relation to the groove base (44) and are preferably bell-shaped.

Abstract: A stator core includes a cylindrical yoke and teeth that are disposed in an inner circumference surface of the yoke along its circumferential direction and that are subjected to magnetic flux from the rotor of the rotating electrical device. The teeth include a trapezoidal tooth that has a trapezoidal cross section that is taken vertically along a central axis of the yoke and an oddly shaped tooth of which a tip section has the same shape as the trapezoidal tooth and a base section from the tip section to the yoke has a different shape from the trapezoidal tooth.

Abstract: Provided is a permanent magnet motor that realizes reduction of both cogging torque and torque ripple, and also downsizing and weight reduction together with torque ripple reduction. When two sets of three-phase armature windings are defined such that a first armature winding 30-1 corresponds to U1 phase, V1 phase, and W1 phase and a second armature winding 30-2 corresponds to U2 phase, V2 phase, and W2 phase, U1 phase is provided in both of any adjacent slots of a plurality of slots 27, or at least one of U1 phase and U2 phase is provided in one of any adjacent slots 27, U1 phase, V1 phase, and W1 phase are shifted by an electric angle of 20° to 40° from U2 phase, V2 phase, and W2 phase upon driving, and a slot opening width Ws of a stator iron core 22 is set to satisfy Ws/(2?Rs/Ns)?0.15, where Rs is an inner radius of the stator iron core and Ns is a slot number of the stator iron core.

Abstract: An electric machine (1), particularly used as an electric motor, has a rotor (2) comprising a plurality of disks (4). A disk (4) of the rotor (2) is divided in a circumferential direction (5) into a plurality of disk sectors (6, 7, 8) between which magnetic pockets (9, 10) are designed. Furthermore, the disk (4) has an inner fastening collar (15) and connecting members (20, 23, 24) connecting the disk sectors (6, 7, 8) to the fastening collar (15). Such a connecting member (20) comprises a main web (21), a side arm (30) branching off the main rib (21) in the circumferential direction (5), and a side arm (31) branching off the main web (21) opposite to the circumferential direction (5). High mechanical stability of the disk (4) can thus be ensured, wherein magnetic flow losses are reduced.

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: Provided is a stator of a motor which is capable of reducing a loss generated in a motor and thereby attaining a high-efficient motor, and a motor including the stator.

Abstract: A motor includes a stator and a rotor, equipped to be movable in at least a first direction relative to the stator, the rotor operably interfacing the stator so that a motor force is generated in a first direction, where the stator comprises an anti-cogging element configured to generate anti-cogging forces on the rotor in at least the first direction and a second direction at an angle to the first direction.

Abstract: An induction motor includes: a stator and a rotor arranged so as to face the stator via a void, the rotor including conductor bars in a plurality of slots formed by a plurality of teeth arranged so as to extend in the circumferential direction of a rotatably held rotor core, wherein the circumferential width of distal end portions of the slots on the radially outside of the rotor core are narrowed by distal end portion of the teeth on the radially outside of the rotor core, and the teeth are each formed with a projection protruding in an arcuate shape from the distal end of the tooth on the radially outside of the rotor core toward the conductor bar in each of the slots.

Abstract: Provided is a stator of a motor which is capable of reducing an iron loss generated in a motor and thereby attaining a high-efficient motor. A stator of a motor comprises a yoke of a tubular shape; and teeth each of which includes an extending portion extending inward in a radial direction of the yoke from the yoke and an increased-width portion formed at a tip end of the extending portion so as to have a greater width than the extending portion in a circumferential direction of the yoke; wherein the extending portion has a narrower portion having a smaller width than a remaining portion of the extending portion.

Abstract: A rotating electric machine includes a case, a plurality of teeth, coils and insulating films. The teeth are circumferentially arranged around a predetermined axis forming a center of the teeth. Each tooth has a first end disposed radially at an opposite side thereof from the predetermined axis. The a back yoke has a circular outer periphery, and a cylindrical inner periphery connecting the first ends of the teeth. The outer periphery has a plurality of concave parts opening radially inwardly toward the teeth at positions overlapping with the teeth as viewed radially. A minimum distance measured from an exposure surface of each tooth to the concave part overlapping therewith is smaller than a radial width of the back yoke at a portion where the concave parts are not provided. The exposure surfaces extend radially inwardly of the inner periphery.

Abstract: To provide an indication motor rotor capable of improving motor performance by concentrating portions under magnetic saturation conditions of rotor teeth. The rotor 1 of an induction motor of this invention may include slots 3 formed approximately in the shape of a T. The slots 3 may be formed so that top slots 3a are arranged on an outer peripheral portion of a rotor core 1a, and bottom slots 3b are arranged on an inner side of the top slots 3a. The width in the circumferential direction of the top slot 3a is wider than the width in the circumferential direction of the bottom slot 3b, and the width in the circumferential direction of a rotor tooth 4 between adjacent top slots 3a is narrower than the width in the circumferential direction of the rotor tooth 4 between adjacent bottom slots 3b.