JP2014225959A - Rotor of dynamo-electric machine and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotor of a dynamo-electric machine which facilitates recycling of metal rare earth, without using adhesive for fixing a permanent magnet, and to provide a manufacturing method therefor.SOLUTION: A rotor 200 of a dynamo-electric machine has a cylindrical rotor core 205, and a plurality of permanent magnets 215 disposed in the magnet insertion holes 210 of the rotor core. The rotor core is constituted of a first rotor core 206 formed by laminating magnetic steel sheets having the magnet insertion holes, and a second rotor core 207 having a magnetic steel sheet on which protrusions 208 are disposed at positions corresponding to the magnet insertion holes. The second rotor core is disposed at the axial end of the rotor core so as to be adjacent to the first rotor core, and the permanent magnets are fixed by the protrusions of the second rotor core in an axial direction.

Description

  The present invention relates to a rotor of a rotating electrical machine and a method for manufacturing the same.

  A rotating electrical machine such as a motor includes a stator and a rotor. The rotor core of the rotor has a plurality of magnet steel plates having a thickness of about 0.05 to 1.0 mm, which has a large number of magnet insertion holes in the circumferential direction, and is provided in a plurality in the circumferential direction of the electromagnetic steel plates. It is integrated by caulking and fixing with a groove. In general, a permanent magnet is embedded in the magnet insertion hole of the rotor core and an adhesive is filled to fix the magnet. The axial and radial fixing of the permanent magnet affects the adhesive state and adhesive strength of the adhesive. However, when further reliability is required, a non-magnetic presser plate that does not impair the magnetic characteristics of the rotating electrical machine is placed in the axial direction. It has a structure in which the permanent magnet is prevented from scattering due to the force applied to the rotating electrical machine.

  For example, in Patent Document 1 (Japanese Patent Application Laid-Open No. 08-126233), when a permanent magnet is fixed to a rotor of a permanent magnet type electric motor having an abduction type rotor with an adhesive, magnetic property deterioration due to the adhesive is prevented. A technique of mixing magnetic powder into an adhesive is disclosed.

Japanese Patent Laid-Open No. 08-126233

  When the permanent magnet is fixed in the magnet insertion hole with an adhesive, strength variations due to the working environment such as temperature and humidity and the working method such as the coating amount are likely to occur, causing a decrease in the fixing strength of the permanent magnet. It was. Therefore, in order to improve the reliability of the product, there is a problem that strict management in the manufacturing process in consideration of the characteristics of the adhesive is necessary.

  In addition, due to the recent rise in the market prices of rare earth metals (neodymium, dysprosium, etc.), a technology for recycling permanent magnets attached to the rotor has attracted attention. However, when removing the permanent magnet fixed by the adhesive from the rotor core, it is necessary to remove the permanent magnet together with the heat-cured adhesive.

  In order to solve the above problems, for example, the configuration described in the claims is adopted. The present application includes a plurality of means for solving the above problems. To give an example, a cylindrical rotor core and a plurality of permanent magnets disposed in the magnet insertion holes of the rotor core are provided. The rotor core includes a first rotor core formed by laminating electromagnetic steel sheets having the magnet insertion holes, and a magnetic steel sheet having protrusions disposed at positions corresponding to the magnet insertion holes. The second rotor core is disposed at an axial end of the rotor core so as to be adjacent to the first rotor core, and the second rotation core The permanent magnet is fixed in the axial direction by the protrusion of the core.

  According to the present invention, it is possible to provide a rotor of a rotating electrical machine that facilitates recycling of a metal rare earth without using an adhesive for fixing a permanent magnet, and a method for manufacturing the same.

It is a mimetic diagram showing the whole rotary electric machine composition concerning an embodiment of the present invention. It is a cross-sectional schematic diagram which shows the rotor and stator of the rotary electric machine which concern on embodiment of this invention. It is the elements on larger scale of the cross-sectional schematic diagram which shows the rotor and stator of the rotary electric machine which concern on embodiment of this invention. It is a cross-sectional schematic diagram which shows the laminated structure of the rotor of the rotary electric machine which concerns on embodiment of this invention. It is a cross-sectional schematic diagram which shows the laminated structure of the rotor of the rotary electric machine which concerns on the 2nd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  In addition, the rotary electric machine which drives an electric vehicle is used as a rotary electric machine explaining each following embodiment. There are two types of electric vehicles that use this rotating electric machine: a hybrid electric vehicle (HEV) that includes both an engine and a rotating electric machine, and a pure electric vehicle (EV) that runs on the rotating electric machine alone without using an engine. Since the rotating electric machine described below can be used for both types, a rotating electric machine for a hybrid type automobile is illustrated here.

[First Embodiment]
FIG. 1 is a schematic diagram showing an overall configuration of a rotating electrical machine 100 according to the present embodiment. In FIG. 1, the inside of the rotating electrical machine 100 is shown by making a part of the rotating electrical machine 100 into a cross section.

  As shown in FIG. 1, the rotating electrical machine 100 is disposed inside a case 105, and includes a stator 300 having a stator core 305 and a rotation disposed rotatably in the stator 300. And a rotor 200 having a child iron core 205. The case 105 includes an engine case and a transmission case.

  The rotating electrical machine 100 is a three-phase synchronous motor with a built-in permanent magnet. The rotating electrical machine 100 operates as an electric motor that rotates the rotor 200 when a three-phase alternating current is supplied to the stator coil 320 wound around the stator core 305. Further, when the rotating electrical machine 100 is driven by an engine, it operates as a generator and outputs three-phase AC generated power. That is, the rotating electrical machine 100 has both a function as an electric motor that generates rotational torque based on electric energy and a function as a generator that generates electric power based on mechanical energy. Functions can be used selectively.

  The stator 300 is fixedly held in the case 105 by fastening a plurality of flanges 315 provided in the circumferential direction to the case 105 with bolts 110.

  The rotor 200 is fixed to a shaft 235 supported by bearings 230 </ b> A and 230 </ b> B of the case 105, and is rotatably held inside the stator core 305.

  The stator 300 and the rotor 200 will be described with reference to FIGS. 2 and 3. 2 is a schematic cross-sectional view showing the rotor 200 and the stator 300 of the rotating electrical machine 100 according to the embodiment of the present invention. FIG. 3 is a schematic cross-sectional view showing the structure of the rotor 200 and the stator 300. It is an enlarged view.

  As shown in FIG. 2, the rotating electrical machine 100 according to the present embodiment includes a stator 300 and a rotor 200 that is rotatably disposed on the inner peripheral side of the stator 300 with an air gap 400 interposed therebetween. It is composed of

  FIG. 3 shows an enlarged view of the part 10. The stator 300 includes a stator core 305 and a stator coil 320.

  The stator core 305 is formed by laminating a plurality of magnetic bodies, for example, a plurality of electromagnetic steel plates in the axial direction, and has a yoke portion (also referred to as a core back portion) and a teeth portion (also referred to as a protruding portion or salient pole portion). It is composed of The yoke portion is composed of a cylindrical yoke core 306 (also referred to as a core back) fitted to the inner peripheral side of the housing. The teeth portion includes a plurality of tea scores 307 that protrude in the radial direction from the inner peripheral side of the yoke core 306 and are arranged in the circumferential direction at a predetermined interval. In the present embodiment, 72 tee scores 307 are formed on the inner peripheral side of the yoke core 306. Thereby, in the present embodiment, the stator 300 having 72 poles of the stator magnetic pole is obtained.

  Each of the adjacent tee scores 307 is continuous in the circumferential direction, and 72 slots 310 are formed on the rotor 200 side. Slot insulation (not shown) is provided in the 72 slots 310, and a plurality of phase windings such as a U phase, a V phase, and a W phase constituting the stator coil 320 are mounted. In the present embodiment, distributed winding is adopted as a method of winding the stator coil 320. Here, the distributed winding is a winding method in which the phase winding is wound around the stator core 305 so that the phase winding is accommodated in the two slots 310 that are separated from each other across the plurality of slots 310. In this embodiment, distributed winding is adopted as the winding method, so that it is possible to control not only a low rotational speed but also a wide rotational speed range up to a high rotational speed by utilizing field weakening control and reluctance torque. Become.

  The rotor 200 includes a rotor core 205 and a permanent magnet 215 held in a magnet insertion hole 210 formed in the rotor core 205.

  In the rotor core 205, rectangular parallelepiped magnet insertion holes 210 are formed at equal intervals in the circumferential direction near the outer periphery, and permanent magnets 215 are embedded in the magnet insertion holes 210. The circumferential width of the magnet insertion hole 210 is formed to be larger than the circumferential width of the permanent magnet 215, and magnetic gaps 220 are formed on both sides of the permanent magnet 215.

  The permanent magnet 215 forms the field pole of the rotor 200. In the present embodiment, one magnetic pole is formed by the four permanent magnets 215. However, one magnetic pole may be formed by a plurality of permanent magnets. By increasing the number of permanent magnets for forming each magnetic pole to a plurality, the magnetic flux density of each magnetic pole emitted from the permanent magnet increases, and the magnet torque can be increased.

  The magnetization direction of the permanent magnet 215 faces the radial direction, and the direction of the magnetization direction is reversed for each field pole. That is, if the surface on the stator side of the permanent magnet 215 for forming a certain magnetic pole is magnetized to the N pole and the surface on the shaft side is magnetized to the S pole, the stator side of the permanent magnet 215 forming the adjacent magnetic pole The surface is magnetized so as to be the south pole and the shaft side surface is the north pole. In the present embodiment, the four permanent magnets 215 are magnetized so that the magnetization direction is alternately changed for each magnetic pole at equal intervals in the circumferential direction, so that the rotor 200 forms 12 magnetic poles. ing.

  The permanent magnet 215 may be embedded in the magnet insertion hole 210 of the rotor core 205 after being magnetized (magnetized), or may be inserted into the magnet insertion hole 210 of the rotor core 205 before being magnetized, and then powerful. It may be magnetized by applying a magnetic field.

  However, the magnetized permanent magnet 215 has a strong magnetic force. If the permanent magnet is magnetized before the permanent magnet 215 is fixed to the rotor 200, the permanent magnet 215 is strong between the rotor core 205 and the permanent magnet 215. A suction force is generated, and this suction force hinders work. Further, dust such as iron powder may adhere to the permanent magnet 215 due to the strong attractive force. Therefore, in order to improve the productivity of the rotating electrical machine 100, it is desirable to magnetize the permanent magnet 215 after inserting it into the magnet insertion hole of the rotor core 205. Here, as the permanent magnet 215, a neodymium-based, samarium-based sintered magnet, a ferrite magnet, a neodymium-based bonded magnet, or the like can be used, but the residual magnetic flux density of the permanent magnet 215 is 0.4 to 1. About 3T is desirable, and a neodymium magnet is more suitable.

  In the present embodiment, auxiliary magnetic poles 225 are formed between the permanent magnets 215 that form the magnetic poles. The auxiliary magnetic pole 225 acts so that the magnetic resistance of the q-axis magnetic flux generated by the stator coil 320 is reduced. The auxiliary magnetic pole 225 causes the reluctance torque to be generated because the magnetic resistance of the q-axis magnetic flux is much smaller than that of the d-axis magnetic flux.

  When a rotating magnetic field is generated in the stator 300 by supplying the three-phase alternating current to the stator coil 320, the rotating magnetic field acts on the permanent magnet 215 of the rotor 200 to generate magnet torque. That is, since the above-described reluctance torque is generated in the rotor 200 in addition to the magnet torque, both the above-described magnet torque and reluctance torque act on the rotor 200 as the rotational torque, resulting in a large rotation. Torque can be obtained.

  FIG. 4 is a schematic cross-sectional view showing a laminated structure of the rotor 200 of the rotating electrical machine 100 according to the present embodiment. The rotor 200 includes a rotor core 205 and a permanent magnet 215.

  The rotor core 205 of the rotor 200 includes a first rotor core 206 formed by laminating electromagnetic steel plates having magnet insertion holes 210, and second rotor cores 207 disposed on both sides in the axial direction. The second stator core 207 is formed with magnet fixing projections 208 extending in the axial direction from the surface of the laminated steel plate. The permanent magnet 215 is pressed and fixed in the axial direction by a magnet fixing projection 208 provided on the second stator core 207 in a state where the permanent magnet 215 is inserted and positioned in the magnet insertion hole 210 disposed in the circumferential direction.

  Since the second stator core 207 for fixing the permanent magnet 215 is a magnetic material, it does not deteriorate the magnetic characteristics of the rotating electrical machine 100, and one laminated steel plate is magnetically with respect to the cross-sectional area of the permanent magnet 215. Since it is thin enough to be ignored, the magnetic characteristics of the rotating electrical machine 100 are not deteriorated.

  Thus, in this embodiment, since the adhesive for fixing the permanent magnet 215 can be reduced, the management man-hour (adhesive filling, adhesive curing process) associated with the use of the adhesive can be reduced.

  In the present embodiment, the permanent magnet 215 is mechanically fixed, so that there is a secondary effect that the magnet can be removed, which is difficult with a magnet fixed with an adhesive. This facilitates recycling of the rare earth metal contained in the permanent magnet.

[Second Embodiment]
A second embodiment of the rotating electrical machine 100 according to the present invention will be described with reference to FIG. FIG. 5 is a schematic cross-sectional view showing the laminated structure of the rotor 200 of the rotating electrical machine 100 according to the second embodiment of the present invention. In the figure, the same or corresponding parts as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  As in the first embodiment, the laminated structure of the rotor core 205 in the present embodiment is arranged on the first rotor core 206 formed by laminating electromagnetic steel plates having the magnet insertion holes 210 and both axial sides thereof. The second rotor core 207 is made up of. In the second rotor core 207 in this embodiment, a magnet fixing projection 209 extending in the axial direction from the surface of the laminated steel plate is formed, and the magnet fixing projection 209 has a spring structure.

  As described above, by fixing the permanent magnet 215 by the pressure of the magnet-fixing protrusion 209 having a spring structure, the reliability of fixing the permanent magnet 215 can be improved.

[Third Embodiment]
Up to the above, the case where the magnetized (pre-magnetized) permanent magnet 215 is fixed has been described. However, the permanent magnet 215 before magnetization can be fixed in the same manner.

  When the magnetized permanent magnet 215 is disposed in the magnet insertion hole 210, it becomes difficult to handle because a magnetic attractive force acts between the magnet steel plate. In consideration of this difficulty in handling, the assembly process of the rotating electrical machine 100 has a structure in which a non-magnetized (post-magnetized) permanent magnet 215 is disposed in the magnet insertion hole 210.

  In this manner, the permanent magnet 215 before magnetization is disposed in the magnet insertion hole 210, and is fixed by the magnet fixing protrusions 208 and 209, and then the permanent magnet 215 is magnetized. A magnetic attraction force acts between the permanent magnet 215 and the magnetic fixing force 208 and the mechanical fixing of the magnet fixing projections 208 and 209, whereby the fixing force of the permanent magnet 215 can be further improved.

  As described above, according to the present invention, it is possible to provide a rotor of a rotating electrical machine that facilitates recycling of a metal rare earth without using an adhesive for fixing a permanent magnet.

  In addition, this invention is not limited to an above-described Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

DESCRIPTION OF SYMBOLS 10 Enlarged part 100 Rotating electrical machine 105 Case 110 Bolt 200 Rotor 205 Rotor core 206 First rotor core 207 Second rotor core 208 Magnet fixed projection 209 Magnet fixed projection 210 Magnet insertion hole 215 Permanent magnet 220 Magnetic gap 225 Auxiliary Magnetic pole 230A Bearing 230B Bearing 235 Shaft 300 Stator 305 Stator core 306 Yoke core 307 Tee core 310 Slot 315 Flange 320 Stator coil 400 Air gap

Claims (4)

A rotor having a cylindrical rotor core and a plurality of permanent magnets arranged in magnet insertion holes of the rotor core,
The rotor core includes a first rotor core formed by laminating electromagnetic steel plates having the magnet insertion holes, and a second rotor core having electromagnetic steel plates provided with protrusions at positions corresponding to the magnet insertion holes. And consists of
The second rotor core is disposed at an axial end of the rotor core so as to be adjacent to the first rotor core;
A rotor that fixes the permanent magnet in the axial direction by the protrusions of the second rotor core. The rotor according to claim 1,
The protrusion has a spring structure;
A rotor in which the spring structure fixes the permanent magnet by applying pressure to the permanent magnet in the axial direction. Comprising the rotor according to claim 1 or 2,
A rotating electrical machine in which the rotor is rotatably arranged on an inner peripheral side of a stator having a plurality of teeth. It is a manufacturing method of the rotor according to claim 1 or 2,
A method for manufacturing a rotor, comprising: arranging the second rotor core at an axial end of the rotor core; and magnetizing a fixed permanent magnet.