Abstract: An induction motor has a rotor core including a plurality of conductor bars and a shorting end ring having a plurality of grooves aligned with and mated to the first ends of the conductor bars. The rotor core further includes a cylindrically shaped steel laminate stack including a plurality of longitudinal grooves distributed around the periphery of the steel laminate stack. The conductor bars are each located in one of the plurality of longitudinal grooves and each includes a first end projecting from a first end of the steel laminate stack. The rotor core further includes an end sheet located to the end of the steel laminate stack, the end sheet including a retention feature configured to retain the shorting end ring to the end sheet.

Abstract: An induction motor includes multiple conductor bars buried and disposed in a rotor core in a circumferential direction, and end rings joined with the multiple conductor bars so as to cause respective both ends thereof to be electrically conducted. Each conductor bar includes a first bar-shape metal portion, and two second metal portions joined with both ends thereof. The second metal portion is formed in a solid block shape. The first and second metal portions are joined with each other by friction stir welding or friction welding.

Abstract: The invention relates to a cage rotor for an asynchronous machine (1) comprising starting bars for improving the starting behavior. The invention further relates to a method for producing such a cage rotor. In order to achieve as great an efficiency as possible, the cage rotor comprises a laminated rotor core (2) having grooves (3) and operating bars (5; 6; 7; 8; 15) disposed in the grooves (3) and contacting the laminated rotor core (2) directly on the inner groove base as seen in the radial direction of the cage rotor, wherein the operating bars (5; 6; 7; 8; 15) comprise partial cladding (9; 10; 11) enclosing an outer surface of the operating bars (5; 6; 7; 8; 15) as seen in the radial direction (12) of the cage rotor, wherein the material of the operating bars (5; 6; 7; 8; 15) comprises a greater specific conductivity than the material of the partial cladding (9; 10; 11).

Abstract: A squirrel-cage rotor of an asynchronous machine, in particular a die-cast rotor, includes a rotatable shaft, a laminated core being rotation-locked on the shaft and having grooves and opposing end faces. A squirrel-cage winding has rotor rods disposed in the grooves and a cage ring disposed on each of the end faces and electrically connecting the rotor rods. A pair of retaining elements is disposed on the shaft, wherein each retaining element extends in a radial direction in form of a disk or a spoke and has in an axial direction a wall and/or an axially extending finger. The wall overlaps on a radial periphery in the axial direction both the cage ring and a predefined axial section of the rotor rods that terminate in the cage ring, without increasing an external diameter of the laminated core.

Abstract: A squirrel-cage rotor of an asynchronous machine includes a laminated core having grooves and positioned in fixed rotative engagement on a shaft, and a squirrel cage including short-circuit rods which are received in the grooves and have opposite front faces, and short-circuit rings which connect the short-circuit rods on the front faces. Shrink rings respectively surround the short-circuit rings at least radially outside and rest on the shaft. A pressure-resistant hardenable plastic is provided in a gap between the short-circuit rings and the shrink rings.

Abstract: A rotor (1) for an induction torque motor according to the present invention comprises an axial body (1a) and a cylindrical body (1b) which is coupled to the axial body (1a) coaxially with the core of the axial body (1a) and is formed with a soft magnetic material wherein the specific electric resistivity is 0.4 [[mu]ohmsm] or less and the specific magnetic permeability is 1000 to 50000. An induction torque motor (TM) according to the present invention comprises the rotor (1) for an induction torque motor. Therefore, the rotor (1) for an induction torque motor and the induction torque motor (TM) according to the present invention can further improve performance.

Abstract: The efficiency of an induction motor is improved while suppressing the generation of magnetic flux saturation of a rotor core. In an induction motor, “a magnetic path width of a rotor” which is the product of a circumferential width of a rotor tooth formed in the rotor and the number of rotor teeth is equal to or larger than “a magnetic path width of a stator” which is the product of a circumferential width of a stator tooth formed in the stator and the number of stator teeth.

Abstract: A rotor for an induction motor includes a rotor core having first and second ends and a plurality of conductor bars. Each conductor bar has a respective first end extending beyond the first end of said rotor core. Each first exposed end has a respective enclosed opening. The rotor also includes an end ring comprising a casting of material flowed between the respective first ends of the conductor bars and through the respective closed openings.

Abstract: A rotor assembly and a method for fabricating the same are provided in which a pair of end caps, positioned at either end of the stack of laminated discs, are fusion welded to the rotor bars using an electron beam welder, thereby yielding improved electrical and mechanical characteristics in a low weight assembly.

Abstract: A BAS machine that includes a specific combination of the number of stator slots to the number of rotor bars to reduce torque ripple without the need for skewing the rotor bars. Particularly, the ratio of the number of stator slots to the number of rotor bars is selected to prevent first and second order harmonics between the stator slots and the rotor bars, where the ratio includes 36/26, 54/44, 72/56, 72/58 or 72/62 for a six pole machine, 48/36, 72/52, 72/58 or 84/86 for an eight pole machine, and 60/44 or 60/46 for a ten pole machine.

Abstract: A rotor includes a shorting ring defining a plurality of cavities therein, and a plurality of conductor bars each integral with the shorting ring and having an end disposed within a respective one of the plurality of cavities. The shorting ring and each of the conductor bars are formed from an aluminum alloy including a lanthanoid present in an amount of from about 0.1 part by weight to about 0.5 parts by weight based on 100 parts by weight of the aluminum alloy. An aluminum alloy, and a method of forming a rotor are also disclosed.

Abstract: The centrifugal casting apparatus comprises: a lower half-mould (10) mounted on a support (12) provided with driving means for rotation about a substantially vertical central axis (14), the lower half-mould (10) being a solid of revolution having a first central cavity (36); an upper half-mould (16) facing the lower half-mould (10), the upper half-mould (16) being a solid of revolution having a second central cavity (56); and means for causing the axial movement of the half-moulds (10, 16) towards and away from each other. The lower half-mould (10) and the upper half-mould (16) each have at least one passage (46, 66) which puts the respective central cavity (36, 56) into communication with the outside through an outlet aperture through which the central axis (14) does not pass.

Abstract: A squirrel-cage rotor includes a laminated core provided on an outer circumference of a rotational axis, and a plurality of slots formed in the laminated core in a circumferential direction, so as to be spaced apart from each other. The cross-section shape of each slot includes an inner circumferential edge and an outer circumferential edge extending in the circumferential direction so as to face each other, and a first side portion and a second side portion extending in a radial direction so as to face each other. The radius of curvature of the inner circumferential edge is larger than that of corners on an inner circumferential side of the slot. The radius of curvature of the outer circumferential edge is larger than that of corners on an outer circumferential side of the slot.

Abstract: The invention comprises a squirrel cage rotor, in particular for use in an asynchronous machine, with a shaft, a laminated rotor core with cage bars and short-circuiting rings arranged within it, at least part of a short-circuiting ring consisting of a disk stack, which is built up in layers from disks with clearances, through which the ends of the cage bars extend out from the laminated rotor core, wherein the disks of a short-circuiting ring have, starting from the lateral surface as the outside face, over the outer circumference at least one bevel or step, which is directed radially inward, and wherein, by their respective bevels or steps, neighboring disks form in the disk stack a slot, in which there is a joining connection, at least in certain portions. The invention also concerns individual parts of a squirrel cage rotor and also a method for the production thereof.

Abstract: An object of the present invention is to provide a squirrel-cage induction motor with high efficiency. In a squirrel-cage induction motor including a stator in which stator windings are wound in a number of stator slots arranged at intervals in the vicinity of the inner periphery of a stator core and a rotor in which rotor conductors are embedded in a number of rotor slots arranged at intervals in the vicinity of the outer periphery of a rotor core and end rings are provided at both ends of the rotor core, the rotor core is formed of a plurality of blocks, an annular short-circuit ring is provided between respective blocks of the rotor core to short-circuit the rotor conductors, and laminated thickness of the rotor core is made larger than laminated thickness of the stator core.

Abstract: The invention relates to a squirrel-cage rotor for an asynchronous machine. In order to increase the electrical efficiency for a cage rotor composed of two materials, the cage rotor comprises a rotor core (1) having grooves (3), end rings (5) of a first material that are cast onto the rotor core on the end face, and conductors (4) that are arranged in the grooves and that are made of a second material that has an electric conductivity that is higher than the electric conductivity of the first material, wherein the conductors (4) comprise a coating (8) made of a coating material on the surface of the conductors, wherein the coating adjoins the second material of the conductors (4) by means of a first alloy layer (2) made of the second material and the coating material and adjoins the cast first material by means of a second alloy layer (9); made of the first material and the coating material.

Abstract: There is provided an induction machine having a squirrel-cage rotor, the rotor including: a rotor core; a plurality of rotor slots formed on the rotor core and aligned circumferentially at a predetermined interval; a plurality of rotor bars inserted into one of the plurality of rotor slots; and a plurality of rotor slits formed adjacent to the plurality of rotor slots on an outer circumferential side of the rotor core. The each rotor slit is formed as a hollow such that a cross sectional shape thereof is distinguished into three parts of a slit outer circumferential part, a slit intermediate part, and a slit inner circumferential part. A circumferential width of the each rotor slit on an innermost circumferential side is larger than that on an outermost circumferential side. A circumferential width of the slit intermediate part increases from an outer circumferential side toward an inner circumferential side.

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: An electric machine includes a stator core defining a number of stator slots (S) extending along a longitudinal axis and angularly spaced about the longitudinal axis. The machine includes a rotor assembly rotatable relative to the stator core and defining first and second ends. The rotor assembly includes a plurality of laminations stacked between the first and second ends. Each respective one of the plurality of laminations defines a number of rotor slots (R) positioned along an outer periphery. A stator slot pitch is defined as 360 divided by the number of stator slots (S). A rotor slot pitch is defined as 360 divided by the number of rotor slots (R) in each respective one of the plurality of laminations. The laminations are skewed relative to each other. An optimal rotor skew angle is determined by the greater of the stator slot pitch and rotor slot pitch.

Abstract: A squirrel cage induction motor includes: a stator core (11); a plurality of stator slots (12) radially disposed in a circumferential direction of the stator core (11) with predetermined intervals; a plurality of stator windings (13) housed in the stator slots respectively; a rotor core (21); a plurality of rotor slots (22) radially disposed in a circumferential direction of the rotor core (22) with predetermined intervals; a plurality of rotor conductors (23) housed in the rotor slots (22) respectively. The stator windings (13) and the rotor conductors (23) includes electrically conductive materials mainly composed of copper. An area ratio of a total area of the stator slots (12) to a total area of the rotor slots (22) is not smaller than 2.7 and not greater than 8.0 to provide compatibility between the starting characteristic (starting torque) and the steady characteristic (for a high efficiency) can be provided.

Abstract: A rotor including a cylindrical iron core having a through hole for receiving a rotational shaft, and a squirrel-cage conductive body including a plurality of conductive bars and a pair of annular conductive end rings provided at both ends of the plurality of conductive bars is provided. The conductive bars extend along a direction in which the rotational shaft is received and are arranged at an outer circumference of the iron core at certain intervals. The rotor further includes a conductive reinforcing layer extends on at least a part of an outer surface of the conductive end ring. The conductive reinforcing layer is formed by spraying conductive particles in a solid phase onto the outer surface of the conductive end ring.

Abstract: A squirrel-cage rotor includes a rotor core formed having a plurality of slots, a plurality of conductor bars inserted into the slots respectively and made of copper or copper alloy, two conductor end rings joined to the plurality of conductor bars on both end faces of the rotor core and made of copper or copper alloy and a reinforcing-member end ring attached to at least one of the conductor end rings and made of material having a specific strength greater than that of either copper or copper alloy. The plurality of conductor bars are arranged so as to extend through the conductor end rings and the reinforcing-member end ring. Consequently, the rotor can be manufactured by any manufacturing method but die-casting. Further, the conductor end rings can be reinforced with an easily-obtainable material and additionally, the junction of conductor end rings can be easily viewed from an outside.

Abstract: The present invention relates to a magnetic actuation method according to which a magnetized mobile (4) is directed by means of at least one magnetic element (2, 2a, 2b) placed opposite said magnetized mobile, characterized in that the preferred direction (or easy axis) of magnetization is made to turn at every point of said element by applying at least one mechanical constraint to said magnetic element(s) (2, 2, 2b), causing anisotropy within said element and thus moving the magnetized mobile in a preferred linear direction or causing the same to rotate.

Abstract: A squirrel cage rotor includes: a rotor core having a plurality of slots formed in a circumferential direction, each slot extending in an axial direction; a plurality of conductive bars housed within the respective slots of the rotor core and having both ends thereof projecting out from end faces in an axial direction of the rotor core; and a pair of end rings disposed at both ends of the rotor core, each end ring having a plurality of fitting portions into which respective end portions of the conductive bar projecting out from the end faces of the rotor core in the axial direction are fitted. A material of the conductive bar is an aluminum alloy having an aluminum component ratio of 99.00% or more, and a material of the end ring is an aluminum alloy having proof stress higher than that of the material of the conductive bar.

Abstract: A method for forming rotor bar slots in an induction machine rotor includes providing a rotor body having an outer circumference, a central axial axis and a radial axis and forming opposed first and second rotor slot sidewalls having profiles diverging outwardly in opposite directions from the rotor radial axis. The opposed first and second rotor slot sidewalls are formed using a cutting tool having a first rotational axis oriented at a first angle outwardly diverging from the radial axis and with a second cutting tool having a second rotational axis oriented at a second angle outwardly diverging from the radial axis that is opposed from the first angle.

Abstract: An induction motor has a rotor core including a plurality of conductor bars and a shorting end ring having a plurality of grooves aligned with and mated to the first ends of the conductor bars. The rotor core further includes a cylindrically shaped steel laminate stack including a plurality of longitudinal grooves distributed around the periphery of the steel laminate stack. The conductor bars are each located in one of the plurality of longitudinal grooves and each includes a first end projecting from a first end of the steel laminate stack. The rotor core further includes an end sheet located to the end of the steel laminate stack, the end sheet including a retention feature configured to retain the shorting end ring to the end sheet.

Abstract: The efficiency of an induction motor is improved while suppressing the generation of magnetic flux saturation of a rotor core. In an induction motor, “a magnetic path width of a rotor” which is the product of a circumferential width of a rotor tooth formed in the rotor and the number of rotor teeth is equal to or larger than “a magnetic path width of a stator” which is the product of a circumferential width of a stator tooth formed in the stator and the number of stator teeth.

Abstract: A method of assembling an induction rotor includes inserting a plurality of conductor bars into a stack of disks whereby distal ends of the conductor bars project from respective axial ends of the stack, placing first and second end rings onto the respective axial ends of the stack so that the ends of the conductor bars fit into slots in the respective end rings, and compressing the slots against the conductor bars by impacting at least one of the end rings. The method may include selectively adjusting an amount of end ring material being compressed by varying heights of respective areas of a top surface of the end ring and/or selectively adjusting an amount of end ring material being compressed by varying heights of respective areas of an impacting surface.

Abstract: A rotor core for an electric motor includes a stack of laminations having peripherally spaced openings receiving copper bars with opposite end portions projecting from the stack. The core is mounted on an arbor and is inserted into a mold on a vertical die cast press having a shot chamber. The mold has upper and lower mold members defining annular cavities receiving end portions of the bars. Molten copper or aluminum is poured into the shot chamber and forced upwardly by a shot piston through passages in the lower mold member and into the cavity around the lower end portions of the bars. The pressurized molten metal solidifies and shrinks around the bar end portions to form an endring for the rotor. The core, endring and arbor are inverted and confined in the mold, and the casting steps are repeated to form the opposite endring.

Abstract: A rotor slot is asymmetrically shaped with respect to a straight line drawn from the central axis of the rotation of the rotor in a radial direction, and has a slot opening, the circumferential width of which is smaller than that of the rotor slot, at the top of the rotor slot, so that a loss generated in the rotor due to a carrier harmonic component can be reduced and the power factor can be improved, enabling a current generated in an armature winding to be suppressed and thereby improving efficiency in a rated operation.

Abstract: Hybrid rotor bar assemblies and electric motors having hybrid rotor bar assemblies are disclosed, as are other aspects. The hybrid rotor tar assemblies have rotor bars lined with shims. The rotor bars can be copper rotor bars. In certain aspects, the shim may be about one fourth to about one eighth of a thickness of the rotor bar. Also disclosed are electric motors with shims lining the rotor bars and functioning as secondary rotor bars.

Abstract: An electric machine with a stator and a rotor. The rotor core is formed by a stack of laminations with the laminations being generally planar and oriented substantially perpendicular to the rotational axis. One of the laminations includes an axially projecting tab. An electically conductive end ring is located at an axial end of the rotor core and is in communication with a plurality of axially extending conductor bars on the rotor core. The tab is coupled with the end ring and resists a portion of the centrifugal forces acting on the end ring during rotation of the rotor. A plurality of such tabs may be used to provide support to the end ring. A method of manufacture is also disclosed.

Abstract: The efficiency of an induction motor is improved while suppressing the generation of magnetic flux saturation of a rotor core. In an induction motor, “a magnetic path width of a rotor” which is the product of a circumferential width of a rotor tooth formed in the rotor and the number of rotor teeth is equal to or larger than “a magnetic path width of a stator” which is the product of a circumferential width of a stator tooth formed in the stator and the number of stator teeth.

Abstract: Induction electrical rotating machine includes a stator which has plural stator slots 114 formed at a predetermined spacing in a circumferential direction of a stator iron core 111 and in which a stator winding 120 is accommodated in the plural stator slots 114, and a rotor 130 in which a rotor bar 132 extending in an axial direction of the rotor iron core 111 is provided in a plural number at a spacing in a circumferential direction and in which a pair of end rings that shorts the plural rotor bars 132 at ends in the axial direction is provided. A shape of a stator-side end, of a sectional shape within a plane orthogonal to a rotor axial direction of the rotor bar 132, is asymmetrical and a notch 133 is formed.

Abstract: An end ring assembly for a rotor, wherein the rotor is rotatable about a central longitudinal axis, includes a plurality of annular sheets stacked adjacent one another. Each of the plurality of annular sheets has a first surface and a second surface spaced opposite the first surface. The end ring assembly also includes a braze material sandwiched between and joining only a first portion of the first surface of each of the plurality of annular sheets, and a corresponding second portion of the second surface of a respective adjacent one of the plurality of annular sheets without joining an entirety of the first surface of each of the plurality of annular sheets and the second surface of the respective adjacent one of the plurality of annular sheets. A method of forming the end ring assembly is also disclosed.

Abstract: A squirrel-cage rotor for asynchronous motors is provided with a lamination stack made of a magnetic material and a plurality of bars, the intermediate portions of which engage respective slots of the lamination stack; the end portions of the bars protrude with respect to the lamination stack at both axial ends of the rotor and are fixed to two shorting rings; a plurality of spaces are defined, axially, by the lamination stack and the shorting rings, and tangentially by the end portions of the bars; part of such spaces is engaged by stiffening blocks arranged in contact with the end portions of the adjacent bars.

Abstract: A rotating electrical machine includes a rotor and a stator including an annular stator core formed by helically stacking a plurality of core pieces that are connected to each other by connecting portions, the rotor being disposed inside an inner periphery of the stator core. The connecting portions are linearly arranged along a stacking direction of the stator core so that grooves that extend in the stacking direction of the stator core are formed in an outer peripheral surface of the stator core at positions where the connecting portions are provided.

Abstract: A method of assembling an induction rotor includes inserting a plurality of conductor bars into a stack of disks, placing first and second end rings onto respective axial ends of the stack, thereby inserting ends of the conductor bars into corresponding slots in the respective end rings, compressing the slots against the conductor bars by impacting the end rings, and applying an electric current through the end rings and conductor bars. The compressing and the applying of current bond end rings and conductor bars together by simultaneous mechanical and electrical heat.

Abstract: The efficiency of an induction motor is improved while suppressing the generation of magnetic flux saturation of a rotor core. In an induction motor, “a magnetic path width of a rotor” which is the product of a circumferential width of a rotor tooth formed in the rotor and the number of rotor teeth is equal to or larger than “a magnetic path width of a stator” which is the product of a circumferential width of a stator tooth formed in the stator and the number of stator teeth.

Abstract: A squirrel-cage rotor includes a rotor core having in its circumferential direction a plurality of slots extending in an axial direction, a plurality of conductor bars stored in each slot of the rotor core and whose ends are projected from an axial direction end surface of the rotor core, and a pair of end rings arranged at the ends of the rotor core and each having a plurality of fitting portions into which the both ends of the conductor bars projecting from the axial direction end surface of the rotor core are fitted. In the conductor bar, among the cross-sectional shape in a plane perpendicular to the axial direction, the shape on the rotor central axis side is a circular arc shape. In the plane perpendicular to the axial direction, a gap is provided on the rotor central axis side of the fitting portion fitted with the conductor bar.

Abstract: A rotor assembly for an electric device includes a laminated stack of electric steel sheets defining a plurality of longitudinally extending grooves. A conductor bar is disposed within each of the grooves. Each of the conductor bars includes a first end and a second end extending longitudinal outward from opposing axial end surfaces of the laminated stack. The first end and the second end of the conductor bars include a textured surface having micro-sized surface irregularities. A first end ring is cast in place over the first ends of the conductor bars, and a second end ring is cast in place over the second ends of the conductor bars. The textured surface in the first ends and the second ends of the conductor bars mechanically interlocking with the cast in place first end ring and second end ring respectively.

Abstract: A rotor of an ultra high speed induction motor includes a stacked body having a plurality of loop type steel sheets stacked to form a cylinder, with a plurality of slots circumferentially formed in a lengthwise direction of the stacked body. Loop type upper, lower end rings are disposed on the upper and lower portions of the stacked body and having a plurality of upper and lower through-holes, respectively, to correspond to the slots. Conductive bars are coated with fusible bonding flux and are inserted into the upper through-holes, the slots, and the lower through-holes such that the conductive bars are integrally bonded into the upper through-holes, the slots, and the lower through-holes, following the fusion and solidification of the fusible bonding flux.

Abstract: A rotor core for an induction motor. The rotor core includes a body that at least (i) extends axially from an outer surface of the body inward toward a central axis, (ii) extends from a first axial end to a second axial end, and (iii) defines a plurality of internal grooves. Further, each groove at least (iv) includes an opening at the outer surface of the body, (v) is defined by two opposing walls, (vi) extends from the first axial end to the second axial end, (vii) extends axially between the opening at the exterior surface and an inward end, and (viii) includes a body section. And wherein (ix) at least one wall of the opposing walls of the groove includes, in the body section of the groove, an extended segment forming a portion of increased breadth for the groove.

Abstract: A piezoelectric element comprises a piezoelectric layer comprising a mixed crystal including at least cerium, bismuth, iron, barium, and titanium and an electrode provided to the piezoelectric layer. The molar ratio of cerium to the total amount of cerium and bismuth in the piezoelectric layer is 0.03 or more and 0.10 or lower.

Abstract: A rotor including a cylindrical iron core having a through hole for receiving a rotational shaft, and a squirrel-cage conductive body including a plurality of conductive bars and a pair of annular conductive end rings provided at both ends of the plurality of conductive bars is provided. The conductive bars extend along a direction in which the rotational shaft is received and are arranged at an outer circumference of the iron core at certain intervals. The rotor further includes a conductive reinforcing layer extends on at least a part of an outer surface of the conductive end ring. The conductive reinforcing layer is formed by spraying conductive particles in a solid phase onto the outer surface of the conductive end ring.

Abstract: A squirrel-cage rotor of an asynchronous machine includes a laminated core having grooves and positioned in fixed rotative engagement on a shaft, and a squirrel cage including short-circuit rods which are received in the grooves and have opposite front faces, and short-circuit rings which connect the short-circuit rods on the front faces. Shrink rings respectively surround the short-circuit rings at least radially outside and rest on the shaft. A pressure-resistant hardenable plastic is provided in a gap between the short-circuit rings and the shrink rings.

Abstract: A squirrel-cage rotor of an asynchronous machine has a rotor bar (4) in a rotor stack (1), wherein the bar (4) can be tipped at a tipping point (11, 12, 13) when the bar (4) has not yet been cast. The rotor bar (4) can in this case have a contour on a radial outer face, wherein the bar (4) can also have a channel (27), the opening (29) in said channel being wider than the shoulders (32, 33) of the limbs (30, 31) which form the channel (27).

Abstract: In one embodiment, a rotor for an induction motor comprises a punching assembly, a plurality of conductive bars, and an end-ring. The plurality of conductive bars may be substantially parallel to an axis of the rotor and connected to the punching assembly at a periphery of the punching assembly. Each conductive bar includes an end connected to the end-ring. The end-ring comprises a punching side having a surface facing the punching assembly and a housing side having a surface opposite the punching surface. The end-ring may be thicker on the punching side than the housing side. In this manner, the peak end ring stresses may be reduced at higher speeds and the mean time between failures of the rotor may be increased. Alternatively, the threshold speed may be increased and the top-speed of the off-highway vehicle may be increased for a given expected mean time between failures of the rotor.

Abstract: A rotor (4) of an induction motor (1) rotatably disposed inside a hollow portion (3) of a stator (2) of the induction motor (1) and rotating under a magnetic force from a magnetic field formed inside the hollow portion (3) by the stator (2). The rotor (4) includes a pair of annular conductors (10, 10), and a plurality of bar-like conductors (11) connected between the pair of annular conductors (10, 10) and configured to form a basket shape along with the pair of annular conductors (10, 10). The annular conductors (10, 10) and the bar-like conductors (11) are respectively formed by a compound material with a conductive core conductor (12) and a carbon nanotube structure (15) attached to an outer periphery of the core conductor (12) in an electric contact state.

Abstract: A rotor of an induction motor according to the present invention is a rotor including a squirrel-cage secondary conductor, wherein the rotor slot is constituted by an outer circumferential slot formed near an outer circumference of the rotor and an inner circumferential slot communicating with the outer circumferential slot and formed inside of the outer circumferential slot, a circumferential width TC of an innermost circumference of the outer circumferential slot is smaller than a circumferential width TD of an outermost circumference of the inner circumferential slot, and a circumferential width of the outer circumferential slot is smaller as the outer circumferential slot approaches to the outer circumference of the rotor.