JP2012019623A - Rotor core - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotor core which can enhance coupling force between adjacent segment pieces of core pieces and improve performance of a rotary electric machine.SOLUTION: A rotor core 11 is configured by laminating a plurality of core pieces 12. In the rotor core 11, a plurality of permanent magnets 15 are buried so as to extend in the lamination direction of the core pieces 12 such that the magnets are disposed at intervals in a circumferential direction. Each of the core pieces 12 is configured by combining segment pieces 12a shaped by division between the permanent magnets 15 via plural fitting parts 16A, 16B in convexoconcave shapes. At least the fitting parts 16A of the fitting parts are arranged outside of a concentric circle C which passes through the gravity center M in each of the permanent magnets 15.

Description

  The present invention relates to a rotor core used in rotating electrical machines such as motors and generators.

  Conventionally, as this type of rotor core, for example, a structure as shown in FIG. 4 is known. The rotor core 21 of this conventional configuration is configured by laminating a plurality of annular core pieces 22 stamped and formed from a sheet material such as a steel plate. Near the outer periphery of each core piece 22, a plurality of pairs of magnet insertion holes 23 are formed at intervals in the circumferential direction. In a state where a plurality of core pieces 22 are laminated, a permanent magnet 24 is embedded in each magnet insertion hole 23 so as to extend in the lamination direction of the core pieces 22.

  However, in the conventional configuration shown in FIG. 4, since the core piece 22 is integrally formed in an annular shape, when the core piece 22 is punched from a hoop material such as a steel plate, There is a problem that a large end material 25 is formed between the core pieces of the hoop material, and the material utilization rate is deteriorated. In order to cope with such a problem, for example, a rotor core having a configuration as shown in FIG. 5 and a configuration as disclosed in Patent Document 1 has been proposed.

  In the conventional configuration shown in FIG. 5, the core piece 22 is constituted by a plurality of divided pieces 22 a having a substantially fan shape divided between the magnet insertion holes 23. Then, in a state in which the core pieces 22 composed of a plurality of divided pieces 22a are laminated, the divided rings 22a of the core pieces 22 are bonded and fixed by shrinking the coupling ring 26 on the outer periphery thereof, so that the rotor core 21 is bonded. Is configured.

  In the conventional configuration described in Patent Document 1, as shown in FIG. 6, the core piece 22 is composed of a plurality of divided pieces 22 a having a substantially fan shape divided between the magnet insertion holes 23. A fitting portion 27 including a convex portion 27a and a concave portion 27b that can be fitted to each other is provided on the opposing joint surface of the adjacent divided pieces 22a. Then, by fitting the convex portion 27a and the concave portion 27b of the fitting portion 27, the adjacent divided pieces 22a are coupled and fixed to form an annular core piece 22, and the core piece. The rotor core 21 is configured by laminating a plurality of 22 sheets.

Japanese Patent Laid-Open No. 2002-262496

However, the conventional configuration has the following problems.
In the conventional configuration shown in FIG. 5, each of the divided pieces 22 a is coupled and fixed by shrinking the coupling ring 26 around the outer periphery of the core pieces 22 including a plurality of divided pieces 22 a stacked. Yes. For this reason, when the coupling ring 26 is contracted, there is a problem that a deviation occurs between the divided pieces 22a of the core pieces 22 in the laminated state, and it is difficult to secure the roundness of the inner diameter portion of the rotor core 21. . Further, since the coupling ring 26 having a predetermined thickness is present on the outer periphery of the rotor core 21, the permanent magnet 24 cannot be embedded close to the outer periphery of the rotor core 21, and there is a problem in that the performance of the rotating electrical machine is reduced. . In addition, since the coupling ring 26 is required, there is a problem that the number of parts increases.

  Furthermore, in the conventional configuration described in Patent Document 1, as shown in FIG. 6, the fitting portion 27 for coupling and fixing the split pieces 22 a is disposed inside the concentric circle C passing through the center of gravity M of each permanent magnet 24. Therefore, in the vicinity of the outer peripheral portion of the rotor core 21, the coupling force between the adjacent divided pieces 22a is weak. Therefore, when a rotor of a rotary electric machine such as a motor or a generator is constituted by the rotor core 21 having the conventional configuration, the centrifugal force acts between the adjacent divided pieces 22a in the vicinity of the outer peripheral portion of the rotor core 21 when the rotor rotates at high speed. A gap due to is easy to occur. In this case, since a large amount of magnetic flux generated from the stator side electromagnetic coil in the rotating electrical machine flows on the outer peripheral surface portion of the rotor, if there is a gap between the divided pieces 22a near the outer peripheral portion of the rotor core 21, the performance of the rotating electrical machine is large. There was a problem of affecting. In addition, when the coupling force between the adjacent divided pieces 22a is weak in the vicinity of the outer peripheral portion of the rotor core 21, there is a problem that the rotor may come into contact with the stator due to deformation due to centrifugal force during high-speed rotation. .

  The present invention has been made paying attention to such problems existing in the prior art. An object of the present invention is to provide a rotor core capable of increasing the coupling force between adjacent divided pieces of the core piece and improving the performance of the rotating electrical machine.

  In order to achieve the above object, the present invention comprises a rotor core in which a plurality of core pieces are laminated and a plurality of permanent magnets are embedded at intervals in the circumferential direction. It is constituted by connecting divided pieces of a shape divided between permanent magnets via a concave and convex fitting portion, and the fitting portion is arranged outside a concentric circle passing through the center of gravity of each permanent magnet. Yes.

  Therefore, in the present invention, the divided pieces in the vicinity of the outer peripheral portion of the rotor core are firmly coupled by the fitting portion disposed outside the concentric circle passing through the center of gravity of each permanent magnet. Therefore, when the rotor of the rotating electrical machine using this rotor core is rotated at a high speed, it is possible to suppress the possibility that a gap is generated between the divided pieces near the outer periphery of the rotor core or the rotor is deformed by centrifugal force. It is possible to improve the performance of the rotating electrical machine. Moreover, since the core piece is composed of a plurality of divided pieces, it is possible to reduce the end material generated when the core piece is punched and formed from a sheet material such as a steel plate, and to improve the material utilization rate. it can.

The said structure WHEREIN: It is good to provide the said fitting part in multiple places of a core radial direction.
The said structure WHEREIN: Each said fitting part is good to arrange | position to the outer side and the inner side of the said concentric circle.
The said structure WHEREIN: It is good to provide a magnetic path division part in the fitting part inside the said concentric circle.

  In the above configuration, the fitting portion may be formed in an ant shape.

  As described above, according to the present invention, the coupling force between the adjacent divided pieces of the core piece can be increased, and the performance of the rotating electrical machine can be improved.

The perspective view which shows the rotor core of one Embodiment. The front view of the rotor core of FIG. The partial enlarged front view which shows the state which assembled | attached the same rotor core to the stator core. The perspective view which shows the conventional rotor core. The front view which shows another structure of the conventional rotor core. The perspective view which shows another structure of the conventional rotor core.

An embodiment of a rotor core embodying the present invention will be described below with reference to FIGS.
As shown in FIGS. 1 and 2, the rotor core 11 of this embodiment is configured by laminating a plurality of annular core pieces 12 and caulking and fixing them in a laminated state at a plurality of uneven caulking portions 13. ing. Near the outer periphery of each core piece 12, a plurality of pairs of magnet insertion holes 14 are formed at intervals in the circumferential direction. And in the lamination | stacking state of the core piece 12, the permanent magnet 15 is embed | buried so that it may extend in the lamination direction of the core piece 12 in each magnet insertion hole 14. As shown in FIG.

  Each of the core pieces 12 is composed of a plurality (eight in the embodiment) of divided pieces 12a that are substantially fan-shaped and divided between the magnet insertion holes 14. A plurality (two in the embodiment) of concave and convex fitting portions 16A and 16B are provided on the opposing joint surfaces of the adjacent divided pieces 12a so as to be juxtaposed in the core radial direction. These fitting parts 16A and 16B are comprised from the dovetail-shaped convex part 16a and the dovetail-shaped recessed part 16b which can be mutually fitted. And the dovetail-shaped convex part 16a of this fitting part 16A, 16B is positioned in the core radial direction and the core circumferential direction between the adjacent divided pieces 12a by being shrink-fitted to the dovetail-shaped concave part 16b. An annular core piece 12 is configured to be coupled and fixed.

  In this case, as shown in FIGS. 2 and 3, among the plurality of fitting portions 16 </ b> A and 16 </ b> B, the outer fitting portion 16 </ b> A in the core radial direction is from a concentric circle C passing through the center of gravity M of each permanent magnet 15. Are also arranged on the outer side, and the inner fitting portion 16B in the core radial direction is arranged on the inner side of the concentric circle C. A gap 17 as a magnetic path dividing part for dividing the magnetic path is provided between the dovetail convex part 16a and the dovetail concave part 16b of the fitting part 16B arranged inside the concentric circle C.

Next, the function of the motor provided with the rotor core configured as described above will be described.
When the motor using the rotor core 11 is rotated, as indicated by solid line arrows in FIG. 3, a magnetic flux MF1 generated from an electromagnetic coil (not shown) on the stator 18 side and formed between the permanent magnets 15 is generated by the rotor core 11. A large amount flows through the outer peripheral surface portion. In this case, the segment 12a of the core piece 12 near the outer periphery of the rotor core 11 is firmly coupled by the fitting portion 16A disposed outside the concentric circle C passing through the center of gravity M of the permanent magnet 15, so that the rotor core No gap is formed between the divided pieces 12a near the outer peripheral portion of 11 or the outer peripheral portion of the rotor core 11 is not deformed by centrifugal force. For this reason, the magnetic flux MF1 effectively flows along the outer peripheral portion of the rotor core 11 without being divided by a gap or the like, and high rotational performance of the motor can be obtained.

  Further, at the time of rotation of the motor, as indicated by a two-dot chain line arrow in FIG. 3, a leakage magnetic flux MF2 is generated at a position on the rotor axis side between the permanent magnets 15 of the adjacent divided pieces 12a. However, since the gap 17 serving as the magnetic path dividing portion is provided in the fitting portion 16B disposed inside the concentric circle C passing through the center of gravity M of the permanent magnet 15, the leakage flux MF2 is divided by the gap 17. For this reason, the effective magnetic flux MF1 flowing in the outer peripheral surface portion of the rotor core 11 is increased, and the rotational performance of the motor is further enhanced.

Therefore, according to this embodiment, the following effects can be obtained.
(1) In this embodiment, the rotor core 11 is configured by laminating a plurality of core pieces 12, and a plurality of permanent magnets 15 are embedded in the rotor core 11 at intervals in the circumferential direction. Each core piece 12 is configured by connecting divided pieces 12a having a shape divided between the permanent magnets 15 via concave and convex fitting portions 16A and 16B. The fitting portion 16 </ b> A is disposed outside a concentric circle C passing through at least the center of gravity M of each permanent magnet 15.

  For this reason, the divided pieces 12 a in the vicinity of the outer peripheral portion of the rotor core 11 can be firmly coupled by the fitting portions 16 </ b> A arranged outside the concentric circle C passing through the center of gravity M of each permanent magnet 15. Therefore, when the rotor of the rotating electrical machine using the rotor core 11 is rotated at a high speed, it is possible to suppress a possibility that a gap is generated between the divided pieces 12a near the outer peripheral portion of the rotor core 11 or the rotor is deformed by centrifugal force. This can improve the performance of the rotating electrical machine. Further, since the core piece 12 is composed of a plurality of sector-shaped divided pieces 12a, the edge material generated when the core piece 12 is stamped and formed from a sheet material such as a steel plate can be reduced, and the material utilization rate Can be improved, and the yield can be improved.

  (2) In the rotor core 11 of this embodiment, the fitting portions 16A and 16B are provided at a plurality of locations in the core radial direction so as to be disposed outside and inside the concentric circle C. For this reason, the division pieces 12a can be firmly coupled over the entire length in the core radial direction by the plurality of fitting portions 16A and 16B.

  (3) In the rotor core 11 of this embodiment, the fitting portions 16A and 16B are constituted by ant-shaped convex portions 16a and ant-shaped concave portions 16b. For this reason, between the divided pieces 12a can be firmly coupled without being displaced in the core radial direction and the core circumferential direction by fitting the dovetail convex portions 16a and the dovetail concave portions 16b.

  (4) In the rotor core 11 of this embodiment, a gap 17 as a magnetic path dividing portion is provided in the fitting portion 16B inside the concentric circle C. For this reason, the leakage magnetic flux MF2 flowing between the permanent magnets 15 of the adjacent divided pieces 12a can be divided by the gap 17 as the magnetic path dividing portion, and the effective magnetic flux MF1 flowing in the outer peripheral surface portion of the rotor is increased. And the performance of the rotating electrical machine can be further improved.

  (5) In the rotor core 11 of this embodiment, the configuration in which the split pieces 12a are connected via the concave and convex fitting portions 16A and 16B without using the conventional coupling ring 26 is adopted. The roundness of the inner diameter portion can be easily secured and the number of parts can be reduced.

(6) In the rotor core 11 of this embodiment, since the conventional coupling ring 26 does not exist, the permanent magnet 15 can be embedded close to the outer periphery of the rotor core 11, suppressing the performance deterioration of the rotating electrical machine, and the rotor core 11. The efficiency of the rotor core 11 can be increased by concentrating the magnetic flux MF1 on the outer periphery of the rotor core 11.
(Example of change)
In addition, this embodiment can also be changed and embodied as follows.

In the above-described embodiment, the concave and convex fitting of the divided pieces 12 a is performed only by the fitting portion 16 </ b> A located outside the concentric circle C passing through the center of gravity M of the permanent magnet 15.
-In the said embodiment, changing the division | segmentation number of the division piece 12a of the core piece 12 arbitrarily.

-In the said embodiment, changing the number of fitting part 16A, 16B between the division pieces 12a arbitrarily.
-In the said embodiment, changing the shape of fitting part 16A, 16B into shapes other than an ant shape, for example, as shown in FIG.

  DESCRIPTION OF SYMBOLS 11 ... Rotor core, 12 ... Core piece, 12a ... Split piece, 15 ... Permanent magnet, 16A ... Outer fitting part, 16B ... Inner fitting part, 16a ... Ant-shaped convex part, 16b ... Ant-shaped concave part, 17 ... Gap as magnetic path dividing part, M ... center of gravity, C ... concentric circles.

Claims (5)

A rotor core in which a plurality of core pieces are laminated and a plurality of permanent magnets are embedded at intervals in the circumferential direction,
The core piece is configured by connecting divided pieces having a shape divided between permanent magnets via a concave and convex fitting portion, and the fitting portion is arranged outside at least a concentric circle passing through the center of gravity of each permanent magnet. A rotor core characterized by that. The rotor core according to claim 1, wherein the fitting portion is provided at a plurality of locations in the core radial direction. The rotor core according to claim 2, wherein each of the fitting portions is disposed outside and inside the concentric circle. The rotor core according to claim 3, wherein a magnetic path dividing portion is provided in a fitting portion inside the concentric circle. The rotor core according to any one of claims 1 to 4, wherein the fitting portion is formed in an ant shape.

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