JP2006025572A - Magnets-embedded motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnets-embedded motor that can decrease torque ripples and cogging torque while controlling reduction in torque. <P>SOLUTION: The magnets-embedded motor is provided with a stator 2 where coil are wound on a plurality of teeth 7 spaced by constant angles in the circumferential direction and formed in such a way as to extend towards the axial center, and a rotor 3 which is rotatably accommodated inside the stator 2 and comprises first to third rotor cores 11 where a plurality of housing holes 21a, 21b, into which V-shaped permanent magnets 14 are accommodated, are provided in the circumferential direction. Both end portions of the housing holes 21a, 21b have outside extension portions 51 that are near the outside circumference of the rotor core 11 at both ends. A pair of the outside extension portions 51 near each other of the housing holes 21a, 21b adjacent in the circumferential direction are all formed in the same shape in each rotor core, but formed in different shapes from a pair of the outside extension portions in the different rotor cores. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an interior magnet type motor.

  As a high efficiency motor, there is an embedded magnet type motor. An embedded magnet type motor is a motor having a rotor in which a permanent magnet is embedded in a rotor core. In addition to a magnet torque between a rotating magnetic field generated by a stator and the rotor, a magnetic path formed in the rotor (magnetic path formation) High motor efficiency can be obtained by effectively utilizing the reluctance torque based on (1).

By the way, the number of teeth generally formed in the stator is set to an integral multiple of the number of permanent magnets (accommodating holes) embedded in the rotor and the number of magnetic path forming portions formed between the permanent magnets. . In general, the permanent magnets and the magnetic path forming portions are formed at equiangular intervals. Therefore, at the predetermined angle when the rotor rotates, the respective circumferential centers of the magnetic path forming portions are in series with each other in the radial direction simultaneously with the circumferential center of the teeth. As a result, a linear coil magnetic flux flow is simultaneously formed (generated) in the magnetic path forming portion, thereby generating a brake torque, and a ripple is generated in the torque output from the motor by the brake torque. In order to reduce this ripple and cogging torque, for example, Patent Document 1 discloses a rotor (rotor) having a skew structure in which a plurality of rotor cores (rotor cores) stacked at an arbitrary height are relatively rotated. ) Is disclosed. This rotor has a skew structure, thereby simultaneously reducing the area of the magnetic path forming portion facing a plurality of teeth, suppressing the flow of linear coil magnetic flux between the teeth and the magnetic path forming portion, and reducing torque ripple and Cogging torque is reduced.
JP-A-5-236687 (FIGS. 1 and 2)

  However, in the motor as described above, the rotor core having the same shape in which the permanent magnet is embedded (the center of each magnetic pole of the permanent magnet) is rotated and laminated in the circumferential direction. The magnetic flux decreases, and there is a concern that the torque of the rotor, which is obtained by the sum of the magnet torque and the reluctance torque, is reduced.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide an embedded magnet type motor that can reduce torque ripple and cogging torque while suppressing a decrease in torque. It is in.

  According to the first aspect of the present invention, a stator having a substantially cylindrical shape and wound around a plurality of teeth formed so as to extend toward the center of the shaft at equal circumferential intervals, and the stator An embedded magnet type motor including a rotor core that is rotatably accommodated inside and has a plurality of rotor cores in the axial direction in which a plurality of accommodation holes for accommodating permanent magnets are provided in the circumferential direction, Both end portions thereof have non-magnetic path end portions close to the outer periphery of the rotor core, and a pair of non-magnetic path end portions adjacent to the accommodation holes adjacent in the circumferential direction are all in the same shape in each of the rotor cores. The pair of non-magnetic path ends in the different rotor cores are formed in different shapes.

  According to a second aspect of the present invention, in the interior magnet type motor according to the first aspect, the number of the rotor cores is a multiple of three, and the number of patterns of the non-magnetic path end portions in the rotor core is three.

  According to a third aspect of the present invention, in the interior magnet type motor according to the second aspect, the pattern of the non-magnetic path ends is such that the pair of non-magnetic path ends are both ends of the permanent magnet. Arranged at the center in the circumferential direction at the end of the permanent magnet, arranged at positions adjacent to each other in the circumferential direction at the end of the permanent magnet, and arranged at positions spaced apart from each other in the circumferential direction at the end of the permanent magnet The three rotor cores in a pattern in which the end portions of the pair of non-magnetic path are both arranged at the center in the circumferential direction at the end portion of the permanent magnet are between the other two core patterns in the axial direction. Placed in.

(Function)
According to the first aspect of the present invention, the pair of nonmagnetic path end portions adjacent to each other in the circumferentially adjacent accommodation holes have the same shape in each rotor core, and the pair of nonmagnetic path end portions in different rotor cores. Are formed in different shapes. Therefore, for example, even if it does not use a skew structure, the area where the magnetic path part which is an outer peripheral part other than the non-magnetic path end part formed on the rotor core simultaneously faces the teeth during rotation becomes small. As a result, the flow of the linear coil magnetic flux between the teeth and the magnetic path portion is suppressed while suppressing the torque reduction based on the permanent magnet, and the torque ripple and the cogging torque are reduced.

  According to the second aspect of the present invention, the number of rotor cores is a multiple of 3, and the number of patterns at the non-magnetic path end portions in the rotor core is three. If it does in this way, torque ripple and cogging torque can be reduced effectively, suppressing the number of patterns of the nonmagnetic path end part in a rotor core, ie, increase in the kind of rotor core.

  According to the third aspect of the present invention, the rotor core having a pattern in which the pair of non-magnetic path ends are arranged in the center in the circumferential direction at the end of the permanent magnet, and the pair of non-magnetic path ends are the ends of the permanent magnet. Between the rotor cores of patterns arranged at positions close to each other in the circumferential direction and the rotor cores of patterns arranged at positions spaced apart from each other in the circumferential direction. If it does in this way, the balance at the time of rotation of a rotor will become favorable because the rotor core which is an intermediate pattern of two patterns is arrange | positioned in the axial center of the other two rotor cores.

  As described above in detail, according to the present invention, it is possible to provide an embedded magnet type motor that can reduce torque ripple and cogging torque while suppressing a decrease in torque.

Hereinafter, an embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, the embedded magnet type motor includes a housing 1, a stator 2, and a rotor 3.
The housing 1 includes a substantially bottomed cylindrical case 4 and a lid 5 for closing the opening (the lower end in FIG. 1) of the case 4. The stator 2 is fixed to the inner peripheral surface of the case 4, and the rotor 3 is rotatable to the inside of the stator 2 by supporting the rotating shaft 6 by bearings 4 a and 5 a provided on the case 4 and the lid 5. Is housed in.

  The stator 2 is formed in a substantially cylindrical shape, and has a plurality of teeth 7 (see FIGS. 3 to 5) formed so as to extend toward the axis center at equal angular intervals in the circumferential direction. And a winding 10 wound through an insulator 9 (see FIG. 1). In the present embodiment, 60 teeth 7 are formed. 3 to 5, the insulator 9 and the winding 10 are not shown. The winding 10 is wound around the tooth 7 by distributed winding.

  As shown in FIG. 1, the rotor 3 includes the rotary shaft 6, first to third rotor cores 11 to 13, and a V-shaped permanent magnet 14 (see FIGS. 2 to 5) as a permanent magnet. The first to third rotor cores 11 to 13 of the present embodiment are formed by laminating a plurality of disk-shaped core sheets. The first to third rotor cores 11 to 13 are set to have the same axial length (thickness). In addition, in FIG.1 and FIG.2, illustration of the boundary line of a several core sheet | seat is abbreviate | omitted. Further, center holes 11a to 13a into which the rotary shaft 6 is fitted are formed at the shaft centers of the first to third rotor cores 11 to 13, respectively. FIG. 2 is a schematic perspective view of the rotor 3 excluding the rotating shaft 6.

  Further, as shown in FIGS. 2 to 5, the first to third rotor cores 11 to 13 penetrate in the axial direction and have a pair of receiving holes 21 a and 21 b that are substantially V-shaped convex radially inward. ˜23a, 23b are formed side by side in the circumferential direction. And in the 1st-3rd rotor cores 11-13, the magnetic path formation parts 31-33 extended in radial direction between the said adjacent V-shape are formed. Further, at both ends of each of the receiving holes 21a, 21b to 23a, 23b, the inner extending portions 41 to 43 are extended so as to reduce the leakage magnetic flux (magnetic flux that immediately goes from the N pole of the magnet to its own S pole). And the outer extension parts 51-53 as a non-magnetic-path edge part are formed (as a part of hole) (refer the partial enlarged view of FIGS. 3-5).

  And in the accommodation holes 21a, 21b to 23a, 23b (excluding the inner extending portions 41 to 43 and the outer extending portions 51 to 53), a V-shaped permanent member arranged in a substantially V shape protruding radially inward. The magnet 14 is accommodated and held. In the present embodiment, the V-shaped permanent magnet 14 is arranged in a substantially V shape by accommodating a pair of quadrangular prism-shaped permanent magnets 14a, 14b in the accommodation holes 21a, 21b-23a, 23b. The adjacent V-shaped permanent magnets 14 are set so that the N pole and the S pole are opposite in the radial direction.

  In the present embodiment, the outer extending portion 51 including the outer peripheral portions other than the outer extending portions 51 to 53 formed on the first to third rotor cores 11 to 13, that is, the magnetic path forming portions 31 to 33. The circumferential direction both sides of -53 comprise the magnetic path part.

  Here, a pair of outer extending portions 51 to 53 (see partial enlarged views in FIGS. 3 to 5) adjacent to the accommodation holes 21 a, 21 b to 23 a and 23 b adjacent in the circumferential direction are all the same in each rotor core. It has a shape (pattern), and is formed in a different shape with respect to the pair of outer extending portions in different rotor cores. That is, the pair of outer extending portions 51 are all in the same shape in the first rotor core 11, and the pair of outer extending portions 52 are all in the same shape in the second rotor core 12. Inside, a pair of outside extension part 53 is made into the same shape altogether. The outer extending portion 51 of the first rotor core 11, the outer extending portion 52 of the second rotor core 12, and the outer extending portion 53 of the third rotor core 13 are formed in different shapes. . Specifically, in the first rotor core 11, the pair of outer extending portions 51 are both arranged at the center in the circumferential direction at the end of the V-shaped permanent magnet 14, as shown in the partially enlarged view of FIG. 3. Further, the second rotor core 12 has a pair of outer extending portions 52 arranged at positions close to each other in the circumferential direction at the end of the V-shaped permanent magnet 14 as shown in the partially enlarged view of FIG. . Further, the third rotor core 13 is disposed at a position where the pair of outer extending portions 53 are spaced apart from each other in the circumferential direction at the end of the V-shaped permanent magnet 14 as shown in the partially enlarged view of FIG. . In the present embodiment, the outer extending portions 52 and 53 of the second and third rotor cores 12 and 13 expand the outer extending portion 51 of the first rotor core 11 in any of the circumferential directions. The shape is set. And the 1st-3rd rotor cores 11-13 of this Embodiment are the order (The order of the 1st rotor core 11, the 2nd rotor core 12, and the 3rd rotor core 13 from the top in FIG.1 and FIG.2). ) And the V-shaped permanent magnets 14 are stacked and arranged so as to be in a straight line.

In the embedded magnet type motor configured as described above, the rotor 3 can be rotationally driven with high motor efficiency using the reluctance torque and the magnet torque as driving forces.
Next, characteristic effects of the above embodiment will be described below.

  (1) A pair of outer extending portions 51 to 53 (see partial enlarged views of FIGS. 3 to 5) adjacent to the accommodation holes 21 a, 21 b to 23 a and 23 b adjacent to each other in the circumferential direction have the same shape in each rotor core. (Pattern), and a pair of outer extending portions in different rotor cores are formed in different shapes. Therefore, even if it is not set as a skew structure, outer peripheral parts other than the outer extension parts 51-53 formed in the 1st-3rd rotor cores 11-13 (the outer extension parts 51- 51 including the magnetic path formation parts 31-33) The area of the magnetic path portion, which is on both sides of 53 in the circumferential direction, simultaneously faces the teeth 7 during rotation is reduced. As a result, the flow of the linear coil magnetic flux between the tooth 7 and the magnetic path portion is suppressed while suppressing the torque reduction based on the V-shaped permanent magnet 14, and the torque ripple and the cogging torque are reduced.

  That is, in the case of a single rotor in which the first to third rotor cores 11 to 13 are three times as long, the first to third characteristics X1 to X3 shown in FIG. Although it becomes large, in the rotor 3 of this Embodiment, it becomes the synthetic | combination characteristic XZ shown in FIG. 7, and a torque ripple and a cogging torque are reduced. In FIG. 6, the first characteristic X1 corresponding to the first rotor core 11 is indicated by a solid line, the second characteristic X2 corresponding to the second rotor core 12 is indicated by a broken line, and the third characteristic corresponds to the third rotor core 13. The third characteristic X3 is indicated by a two-dot chain line. In FIG. 7, the composite characteristic XZ is indicated by a bold line.

  (2) The number of rotor cores is a multiple of 3 (first to third rotor cores 11 to 13), and the number of patterns of the outer extending portions 51 to 53 in the rotor core (first to third rotor cores 11 to 13). Is three. If it does in this way, torque ripple and cogging torque can be reduced effectively, suppressing the increase in the kind (cost increase) of a rotor core.

The above embodiment may be modified as follows.
In the above embodiment, the first to third rotor cores 11 to 13 are arranged in the order (in FIG. 1 and FIG. 2, the first rotor core 11, the second rotor core 12, and the third rotor core 13 from the top. However, it may be changed and stacked in other order. For example, the second rotor core 12, the first rotor core 11, and the third rotor core 13 may be stacked in this order. If it does in this way, it is an intermediate pattern of two patterns (the outer extending part 51 is arrange | positioned in the circumferential direction center in the edge part of the V-shaped permanent magnet 14, as shown in the partial expanded view of FIG. 3). By arranging the first rotor core 11 at the center in the axial direction of the other second and third rotor cores 12 and 13, the balance during rotation of the rotor is good.

  In the above embodiment, the number of rotor cores is three (first to third rotor cores 11 to 13), and the patterns of the outer extending portions 51 to 53 in the rotor core (first to third rotor cores 11 to 13) However, these numbers may be changed.

Moreover, although the axial direction length (thickness) of each rotor core (the 1st-3rd rotor cores 11-13) was set the same, you may make axial length different.
For example, as illustrated in FIG. 8A, the number of rotor cores is two (first and second rotor cores 61 and 62), and the outer extending portion in the rotor core (first and second rotor cores 61 and 62). The number of patterns may be two (for example, the same as the first and second rotor cores 11 and 12 in the above embodiment). In this example, the ratio of the axial lengths of the first rotor core 61 and the second rotor core 62 is 1: 2.

  Further, for example, as shown in FIG. 8B, the number of rotor cores is four (first to fourth rotor cores 66 to 69), and the outer extension of the rotor core (first to fourth rotor cores 66 to 69) is increased. You may make the number of the pattern of an installation part into four. In this example, the axial lengths of the first to fourth rotor cores 66 to 69 are the same.

Further, for example, as shown in FIGS. 9A to 9C, the number of rotor cores may be four or more while the number of patterns of the outer extending portions is three.
That is, as shown in FIG. 9A, the pattern of the outwardly extending portions of the first and fourth rotor cores 71 and 74 among the first to sixth rotor cores 71 to 76 is set, for example, in the first embodiment. The same as that of the first rotor core 11. Also, the pattern of the outer extending portions of the second and fifth rotor cores 72 and 75 is the same as that of the second rotor core 12 of the above embodiment, for example. Further, the pattern of the outer extending portions of the third and sixth rotor cores 73 and 76 is the same as that of the third rotor core 13 of the above-described embodiment, for example. And the 1st-6th rotor cores 71-76 are laminated | stacked and arrange | positioned in the order. In this example, the ratio of the axial lengths of the first to sixth rotor cores 71 to 76 is set to 2: 1 to 2 to 2 to 1 to 2.

  Further, as shown in FIG. 9B, the pattern of the outwardly extending portions of the first and sixth rotor cores 81 and 86 among the first to sixth rotor cores 81 to 86 is set, for example, in the first embodiment. The same as that of the first rotor core 11. In addition, the pattern of the outer extending portions of the second and fourth rotor cores 82 and 84 is the same as that of the second rotor core 12 of the above embodiment, for example. Also, the pattern of the outer extending portions of the third and fifth rotor cores 83 and 85 is the same as that of the third rotor core 13 of the above-described embodiment, for example. And the 1st-6th rotor cores 81-86 are laminated | stacked and arrange | positioned in the order. In this example, the ratio of the lengths in the axial direction of the first to sixth rotor cores 81 to 86 is set to 2: 1: 2: 1: 2: 2.

  Further, as shown in FIG. 9C, the pattern of the outwardly extending portions of the first and fourth rotor cores 91 and 94 among the first to fifth rotor cores 91 to 95 is, for example, the first embodiment. The same as that of the first rotor core 11. Further, the pattern of the outwardly extending portion of the third rotor core 93 is the same as that of the second rotor core 12 of the above embodiment, for example. In addition, the pattern of the outer extending portions of the second and fifth rotor cores 92 and 95 is the same as that of the third rotor core 13 of the above embodiment, for example. And the 1st-5th rotor cores 91-95 are laminated | stacked and arrange | positioned in the order. In this example, the axial lengths of the first to fifth rotor cores 91 to 95 are the same.

  Further, for example, the number of patterns of the outer extending portions may be changed to four or more. In this case, the positions of the pair of outer extending portions are adjacent to each other in the circumferential direction at the end portions of the permanent magnet. It may be changed in a stepwise manner (for example, evenly) from a position to a position away from it.

  In the above embodiment, the magnetic path forming parts 31 to 33 of the first to third rotor cores 11 to 13 are equiangularly spaced (equal pitch), but the magnetic path forming part of at least one rotor core is You may change so that it may not become an equiangular space | interval (it may become unequal pitch). That is, at least one of the rotor cores is connected in series with the circumferential center of the teeth in the radial direction in the magnetic path forming portion extending in the radial direction between the accommodation holes (permanent magnets) adjacent in the circumferential direction. In this state, the circumferential center of the magnetic path forming portions adjacent in the circumferential direction may be set so as to be shifted from the circumferential center of the teeth. For example, as shown in FIG. 10A, out of the first and second rotor cores 96, 97, the first rotor core 96 may have an equal pitch, and the second rotor core 97 may have an unequal pitch. Further, for example, as shown in FIG. 10B, among the first to third rotor cores 98 to 100, the first and third rotor cores 98 and 100 are set at an equal pitch, and the second rotor core 99 is unequal. It is good also as a pitch. In this example, the ratio of the axial lengths of the first to third rotor cores 98 to 100 is set to 2 to 2 to 1.

  In the above embodiment, the first to third rotor cores 11 to 13 are stacked and arranged so that the V-shaped permanent magnet 14 is in a straight line, but the magnetic pole center of the permanent magnet is the same as the skew structure. You may arrange | position and arrange | position so that it may slip | deviate to the circumferential direction. Even in this case, for example, the amount by which the magnetic pole center is shifted in the circumferential direction is made smaller than in the prior art, and the reduction of the effective magnetic flux of the permanent magnet is suppressed, that is, the torque ripple and the torque reduction are suppressed. Cogging torque can be reduced.

  For example, as shown in FIG. 11A, in the first and second rotor cores 101 and 102 (the pattern of the outer extending portion is the same as, for example, the first and second rotor cores 11 and 12 in the above embodiment). The magnetic pole centers Y1, Y2 of the respective permanent magnets (V-shaped permanent magnets 14) may be laminated and arranged so as to be displaced in the circumferential direction. In FIG. 11A, one of a plurality of magnetic pole centers in each rotor core is indicated by a two-dot chain line.

  Further, for example, as shown in FIG. 11B, the first to third rotor cores 106 to 108 (the pattern of the outer extending portion is the same as that of the first to third rotor cores 11 to 13 of the above embodiment, for example). ) May be arranged so that only the magnetic pole center Z2 of the second rotor core 107 is displaced in the circumferential direction. In FIG. 11B, one of the plurality of magnetic pole centers in each rotor core is indicated by a two-dot chain line. In this example, the ratio of the axial lengths of the first to third rotor cores 106 to 108 is set to 2 to 2 to 1.

-In above-mentioned embodiment, although accommodation hole 21a, 21b-23a, 23b and the permanent magnet (V-shaped permanent magnet 14) were made into substantially V shape, it is not limited to this, You may change into another shape. .
For example, as shown in FIG. 12, the accommodation hole and the permanent magnet may be changed to a curved accommodation hole 111 and a permanent magnet 112 that are convex in the radial direction. In FIG. 12, only one rotor core 113 among the plurality of rotor cores is shown, but the other holes in the other rotor cores (not shown) have the same shape for the receiving holes and the permanent magnets but only the outer extending portions 114 are different. The

  Further, for example, as schematically shown in FIG. 13 (a), there are four accommodation holes and permanent magnets in the circumferential direction (only two are shown), and the linear accommodation holes 121 along the circumferential direction and The permanent magnet 122 may be changed. Further, for example, as schematically shown in FIG. 13B, there are four accommodating holes and permanent magnets in the circumferential direction (only two are shown), and the curved accommodating hole 123 whose inner side in the radial direction is convex. Further, the permanent magnet 124 may be changed. Further, for example, as schematically shown in FIG. 13 (c), there are four accommodating holes and permanent magnets in the circumferential direction (only two are shown), and a linear portion along the circumferential direction and radial directions from both ends thereof. You may change into the accommodation hole 125 and the permanent magnet 126 which consist of the extending part extended outside. Of course, also in other rotor cores (not shown) in these examples (FIGS. 13A to 13C), the receiving holes and the permanent magnets have the same shape, but only the outer extending portions are different.

  The first to third rotor cores 11 to 13 of the above embodiment may be laminated via the nonmagnetic material 131 as shown in FIG. 14A, or as shown in FIG. You may laminate | stack via the space | gap 132 (forming a clearance gap). If it does in this way, magnetic flux leakage between the 1st-3rd rotor cores 11-13 will be prevented by nonmagnetic material 131 or space 132. Therefore, a decrease in torque can be suppressed.

  In the above embodiment, the first to third rotor cores 11 to 13 are formed by laminating a plurality of disk-shaped core sheets, but may be of the same shape, for example, magnetic powder May be formed by sintering.

The technical idea that can be grasped from the above embodiments will be described below together with the effects thereof.
(A) In the interior magnet type motor according to any one of claims 1 to 3, at least one of the rotor cores is radially between the accommodation hole and the permanent magnet adjacent in the circumferential direction. The circumferential center of the magnetic path forming portion adjacent to the circumferential direction is the center in the circumferential direction of the teeth, with the circumferential center in the magnetic path forming portion extending in the radial direction in series with the circumferential center of the teeth. An embedded magnet type motor which is set so as to be displaced with respect to the motor.

  In this case, since the respective circumferential centers of adjacent magnetic path forming portions and the circumferential center of the teeth are not in series in the radial direction at the same time, linear coil magnetic fluxes are simultaneously generated in adjacent magnetic path forming portions. Is prevented from forming (occurring). Therefore, torque ripple and cogging torque are reduced.

  (B) In the embedded magnet type motor according to any one of claims 1 to 3 and (A), the plurality of rotor cores are stacked via a non-magnetic material or a gap. Embedded magnet type motor. If it does in this way, since a plurality of rotor cores are laminated via a nonmagnetic material or a space, magnetic flux leakage between rotor cores is prevented. Therefore, a decrease in torque can be suppressed.

The side sectional view of the interior magnet type motor in this embodiment. The schematic perspective view of the rotor except a rotating shaft in this Embodiment. The top view of the stator and 1st rotor core in this Embodiment. The top view of the stator and 2nd rotor core in this Embodiment. The top view of the stator and 3rd rotor core in this Embodiment. The angle-torque characteristic view for explaining the first to third characteristics. The angle-torque characteristic diagram for demonstrating the synthetic | combination characteristic in this Embodiment. (A) (b) The model perspective view of the rotor in another example. (A)-(c) The model perspective view of the rotor in another example. (A) (b) The model perspective view of the rotor in another example. (A) (b) The model perspective view of the rotor in another example. The top view of the rotor in another example. (A)-(c) The partial schematic plan view of the rotor in another example. (A) (b) The model perspective view of the rotor in another example.

Explanation of symbols

  2 ... Stator, 3 ... Rotor, 7 ... Teeth, 10 ... Winding, 11-13, 61, 62, 66-69, 71-76, 81-86, 91-95, 96-102, 106-108, 113 ... 1st-6th rotor core (rotor core), 14 ... V-shaped permanent magnet (permanent magnet), 21a, 21b-23a, 23b, 111, 121, 123, 125 ... accommodation hole, 51-53 ... outside extension part (Non-magnetic path end), 112, 122, 124, 126 ... permanent magnets.

Claims (3)

A stator in which a winding is wound around a plurality of teeth that are formed in a substantially cylindrical shape and extend toward the axis center at equal angular intervals in the circumferential direction;
An embedded magnet type motor including a rotor that is rotatably accommodated inside the stator and has a plurality of rotor cores in the axial direction in which a plurality of accommodation holes for accommodating permanent magnets are provided in the circumferential direction,
The accommodation hole has a non-magnetic path end portion whose both end portions are close to the outer periphery of the rotor core,
A pair of the non-magnetic path end portions adjacent to each other in the circumferential direction adjacent to each other in the circumferential direction has the same shape in each of the rotor cores, and has a different shape with respect to the pair of non-magnetic path end portions in the different rotor cores. An embedded magnet type motor characterized by being formed. The interior magnet type motor according to claim 1,
The number of the rotor cores is a multiple of 3, and the number of patterns of the non-magnetic path end portions in the rotor core is three. The interior magnet type motor according to claim 2,
The pattern of the non-magnetic path end is
The pair of the non-magnetic path end portions are both disposed at the center in the circumferential direction at the end portion of the permanent magnet, the end portions of the permanent magnet are disposed at positions adjacent to each other in the circumferential direction, and Three of the permanent magnets are arranged at positions separated from each other in the circumferential direction at the end of the permanent magnet,
The rotor core having a pattern in which the pair of non-magnetic path end portions are both arranged at the center in the circumferential direction at the end portion of the permanent magnet is arranged between the other two patterns of the rotor core in the axial direction. Features a built-in magnet motor.

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