Abstract: A rotor outer peripheral surface includes first arcs and second arcs. The first arc is positioned in a magnetic pole center portion. The second arc is positioned in an inter-pole portion. The first arc bulges toward a radially outer side to a higher degree than the second arc. An air gap is varied in a manner of being increased as approaching from each of the magnetic pole center portions to the adjacent inter-pole portions. A hole defining portion of a magnet insertion hole on the radially outer side has a curvature of a third arc, and a hole defining portion of the magnet insertion hole on a radially inner side has a curvature of a fourth arc. An opening angle of a tooth tip portion, an opening angle of the first arc, and an opening angle of the third arc coincide with each other.

Abstract: In an interior permanent magnet motor, at least one magnetic pole center slit and a plurality of side slits are formed between a rotor outer peripheral surface of a rotor and a radially-outer insertion hole contour surface of a magnet insertion hole. The plurality of side slits are formed so that at least one side slit is formed on each of both sides of the magnetic pole center slit in a width direction. The area of the magnetic pole center slit is smaller than the area of each of the plurality of side slits. A width of each of the plurality of side slits is larger than an interval between the adjacent slits.

Abstract: In an interior permanent magnet motor, a magnet insertion hole of a rotor core is curved into an arc shape, and a convex portion side of the arc shape is arranged on a center side of a rotor. The magnet insertion hole has a first line, a second line, and a pair of third lines. The first line is located on the radially outer side of the second line. Each of the third lines connects the first line and the second line to each other. The first line includes an arc portion and a pair of concave portions. Each of the concave portions is located at an end of the arc portion of the first line.

Abstract: Provided is an interior permanent magnet motor, including: a stator; and a rotor, in which an outline of each of magnet insertion holes includes a radially inner-side line, a radially outer-side line, a pair of side lines, a pair of first round portions, and a pair of second round portions, in which a thin portion is formed between an outer peripheral surface of the rotor and each of the side lines, in which each of the first round portions is provided between a corresponding end of the corresponding radially outer-side line and a corresponding end of the corresponding side line, and in which each of the second round portions is provided between a corresponding end of the corresponding radially inner-side line and a corresponding end of the corresponding side line.

Abstract: A rotor iron core includes: a plurality of first iron cores and arranged in an outer side in a radial direction of each permanent magnet; and a second iron core with mechanical strength higher than mechanical strength of each first iron core and that includes an inner iron core arranged on an inner side in the radial direction of each permanent magnet and a plurality of inter-magnetic pole iron cores formed integrally with the inner iron core and arranged between magnetic poles of each permanent magnet, wherein each inter-magnetic pole iron core is formed from an end part in a circumferential direction of each first iron core to the inner iron core, and a flux barrier is formed between each permanent magnet and each inter-magnetic pole iron core.

Abstract: A rotor is connected to a shaft member and rotates about a central axis. The rotor includes a shaft hole having at least part of the shaft member disposed therein; and flow paths disposed around the shaft member and penetrating the rotor in a direction parallel with the central axis. Each flow path has a first surface facing outward in the radial direction; a second surface disposed outward of the first surface in the radial direction and facing the first surface; a third surface connecting the first and second surfaces at one end in a rotational direction about the central axis; a fourth surface connecting the first and second surfaces at the other end in the rotational direction. The condition C<D is satisfied, where C is the distance between both ends of the first surface, and D is the distance between both ends of the second surface.

Abstract: A motor including a rotor, and a stator having a plurality of coils wound around slots, wherein at least any one of the coils includes a single aluminum wire, a single copper wire joined to the aluminum wire, a stranded wire (lead wire) joined to the copper wire, a cold-pressure-welded joint portion (joint portion) joined between the aluminum wire and the copper wire by cold pressure welding, and a non-pressure welded joint portion (joint portion) provided between the copper wire and the stranded wire (lead wire). A burr covered by an insulation member (insulation tube) is provided in the cold-pressure-welded joint portion (joint portion). A thickness of the insulation member (insulation tube) is larger than a height of the burr.

Abstract: A drive circuit for a synchronous motor including a rotor having ten magnetic poles formed by a permanent magnet, and a stator in which a winding is wound in a concentrated manner around nine teeth facing the rotor, the drive circuit including: an inverter including a plurality of switching elements in bridge connection; and a control unit that controls the inverter in such a manner that a square-wave-shaped current flows to the winding, wherein the control unit operates in such a manner that an energization phase at which to pass the square-wave-shaped current falls within a range of electric angles of ?10° to +5° from an energization phase at which the current is minimum when a target torque of the synchronous motor is generated.

Abstract: A rotor of an interior permanent magnet motor includes a rotor core; permanent magnet insertion holes formed in an outer circumferential portion of the rotor core along a circumferential direction; a permanent-magnet end-portion air gap formed in each of both end portions of each permanent magnet insertion hole; a permanent magnet inserted in each permanent magnet insertion hole; and slits formed in an outer circumferential core portion on an outer side in a radial direction with respect to each permanent magnet insertion hole, wherein a width of a core present between the permanent-magnet end-portion air gap and the slit and a width of a core present between the slits are such that a width of a core gradually increases as the core is closer to a magnet pole center from the interpolar line.

Abstract: An interior permanent magnet motor includes a stator and a rotor. The rotor includes a rotor core having a plurality of magnet receiving holes, and a plurality of permanent magnets are received in each of the magnet receiving holes. A plurality of slits are formed at a part between an outer peripheral surface of the rotor and an outer-side defining line of the each of the magnet receiving holes. At least one space portion is secured between the plurality of permanent magnets, and the space portion is opposed to any one of the plurality of slits in a direction parallel to a magnetic pole center line.

Abstract: Provided is an interior permanent magnet motor including: a stator; and a rotor, the rotor including separated permanent magnets for one magnetic pole, in which: a rotor core includes the same number of separated magnet insertion holes as that of the plurality of permanent magnets for one magnetic pole; bridges are formed between respective adjacent ones of the magnet insertion holes in each magnetic pole; each of the bridges includes a pair of parallel linear portions and two pairs of curved portions; under a state in which the permanent magnets are inserted into the magnet insertion holes, the pair of linear portions are in contact with edge surfaces of the permanent magnets; the pair of curved portions are connected to ends of the linear portions; and an interval between the pair of curved portions becomes larger as the interval becomes away from the linear portions.

Abstract: An interior permanent magnet motor includes a stator and a rotor rotatably arranged so as to be opposed to the stator. The rotor includes a rotor core having a plurality of magnet insertion holes formed therein, into which corresponding permanent magnets are respectively inserted. The plurality of permanent magnets and the plurality of magnet insertion holes are each formed into an arc shape that is convex toward a center side of the rotor. When a shortest distance between the adjacent magnet insertion holes is defined as an inter-pole shortest distance (L), a ratio of the inter-pole shortest distance (L) to an outer diameter (D) of the rotor is 0.035?L/D?0.045.

Abstract: A permanent magnet embedded electric motor includes a stator core disposed inside the frame and having a back yoke and a plurality of magnetic pole teeth; a rotor disposed on an inner diameter side of the plurality of magnetic pole teeth; and compression sections in which compression stress higher than compression stress occurring in the back yoke due to pressing force generated between the frame and the back yoke occurs. A compression section group having a set of two or more compression sections and of the plurality of compression sections is disposed on an outer circumferential section of the stator core. A sum of the rotating direction widths of the plurality of compression sections constituting the compression section group is smaller than a radial direction thickness of the frame.

Abstract: An interior permanent magnet motor includes a stator and a rotor. The rotor includes a rotor core formed by laminating a plurality of plate members. The rotor core has a plurality of magnet insertion holes formed therein, into which corresponding permanent magnets are respectively inserted. At least one slit and at least one caulked portion are formed between a rotor outer peripheral surface of the rotor and a radially-outer insertion hole contour surface of the magnet insertion hole. At least a part of the caulked portion is positioned between a pair of width extended lines of the slit.

Abstract: An interior permanent magnet motor includes: a rotator; a stator; a permanent magnet inserted into a magnet accommodating hole; and a slit formed on a radially outer side of the magnet accommodating hole. A space portion is ensured between a radially outer surface of the permanent magnet and a rotator core in each region opposed to the slit. The permanent magnet is apart from the rotator core via the space portion in the each region opposed to the slit.

Abstract: In an interior permanent magnet motor, a plurality of slits are formed between a rotor outer peripheral surface of a rotor and a radially-outer insertion hole contour surface of a magnet insertion hole. Assuming that a total area of the plurality of slits per magnetic pole is represented by Ss, and an area of a region in a rotor core on a radially outer side with respect to the corresponding one magnet insertion hole is represented by Si, the plurality of slits are formed so as to satisfy a relationship of 0.35?Ss/Si?0.5.

Abstract: In an interior permanent magnet motor, at least one magnetic pole center slit and a plurality of side slits are formed between a rotor outer peripheral surface of a rotor and a radially-outer insertion hole contour surface of a magnet insertion hole. The plurality of side slits are formed so that at least one side slit is formed on each of both sides of the magnetic pole center slit in a width direction. The area of the magnetic pole center slit is smaller than the area of each of the plurality of side slits. A width of each of the plurality of side slits is larger than an interval between the adjacent slits.

Abstract: A synchronous motor includes a stator that includes nine teeth that are divided into three phases, each of which includes three adjacent teeth, windings being concentratedly wound around the teeth. The circumferential width of a tip portion of a central tooth among three teeth forming each phase is made smaller than the circumferential widths of tip portions of both-side teeth, and the tooth thickness of the tip portion of the central tooth is made smaller than the tooth thicknesses of the tip portions of the both-side teeth.

Abstract: In an interior permanent magnet motor, each of permanent magnets has a radially-inner magnet contour surface, a radially-outer magnet contour surface, and a pair of side-end magnet contour surfaces. Each of magnet insertion holes has a radially-inner insertion hole contour surface, a radially-outer insertion hole contour surface, and a pair of side-end insertion hole contour surfaces. The radially-outer magnet contour surface and the radially-outer insertion hole contour surface are each formed by a first arc surface. The radially-inner magnet contour surface and the radially-inner insertion hole contour surface are each formed by a second arc surface and at least one straight surface configured to suppress movement of the permanent magnet along the magnet insertion hole having an arc shape.

Abstract: A permanent magnet embedded motor includes a rotor and permanent magnets. The outer circumferential surface of the rotor is formed by divided outer circumferential surfaces divided at equal angle intervals in a circumferential direction corresponding to permanent magnets. The divided outer circumferential surface is formed by a first curved surface, a radial direction distance of which from a rotor axis is maximized in a circumferential direction center of divided outer circumferential surface and second curved surfaces formed from the circumferential direction both ends to the circumferential direction center and crossing the first curved surface. The second curved surfaces are formed by—arcuate surfaces each having the rotor axis as a central axis. A distance between both ends of the first curved surface is smaller than the width of a permanent magnet in a direction orthogonal to a radial direction in the circumferential direction center.