Rotor of a rotating electrical machine, and method for manufacturing the rotor

Abstract

To suitably fix a magnet in a housing hole of a rotor core.SOLUTION: A rotor comprises a rotor core 21 and a plurality of permanent magnets housed in each housing hole 23 of the rotor core 21. The permanent magnet consists of two split magnets 22a, 22b arranged in the circumferential direction in the housing hole 23. The two split magnets 22a, 22b are gathered to one side so that core thickness in the radial direction among both sides in the radial direction of the housing hole 23 is close to a first side face 23a of a thick side in the radial direction and are gathered to one side to be respectively close to second side faces 23c, 23d in the circumferential direction. In the housing hole 23, a filler 24 is filled into a separation part between the permanent magnet and the rotor core 21 formed by gathering each split magnet 22a, 22b to one side in the radial direction and the circumferential direction.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The disclosure in this specification relates to a rotor of a rotating electrical machine and a method for manufacturing the rotor.

Background Art

[0002] In a configuration having an embedded magnet type rotor (IPM rotor) as a rotating electrical machine, it is conceivable that the fixed positions of the permanent magnets vary within the magnet accommodation holes. In this case, along with the variation in the fixed positions of the permanent magnets, an increase in the rotational imbalance and torque ripple of the rotor, a decrease in the induced voltage, etc. may occur, and there is concern that the motor characteristics may deteriorate.

[0003] Also, in order to eliminate such inconveniences, for example, in the technique described in Patent Document 1, among the first and second surfaces of the permanent magnet that face each other, the first surface and the rotor core are adhesively fixed via a foaming adhesive that foams and cures by heating, while the second surface and the rotor core are adhesively fixed via a thermosetting adhesive that does not foam by heating. And according to this configuration, it is assumed that the position of the permanent magnet within the magnet accommodation hole can be made constant according to the foaming ratio of the foaming adhesive.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the technique of the above Patent Document 1, as a fixing means for the permanent magnet within the magnet accommodation hole, it is necessary to prepare two types of adhesives: a foaming adhesive that foams and cures by heating and a thermosetting adhesive that does not foam by heating. Therefore, there is concern that the operation of fixing the permanent magnet within the magnet accommodation hole may become complicated.

[0006] The present invention has been made in view of the above circumstances, and an object thereof is to provide a rotor of a rotating electrical machine capable of properly fixing a magnet in an accommodation hole of a rotor core, and a method for manufacturing the rotor.

Means for Solving the Problems

[0007] A plurality of aspects disclosed in this specification employ different technical means in order to achieve their respective objects. The objects, features, and effects disclosed in this specification will become clearer by referring to the subsequent detailed description and the attached drawings.

[0008] Means 1 is A rotor of a rotating electrical machine including a rotor core made of a soft magnetic material and a plurality of magnets respectively accommodated in a plurality of accommodation holes provided at predetermined intervals in the circumferential direction in the rotor core, wherein the magnets are fixed by a filling agent filled in the accommodation holes, The rotor core has different core thicknesses in the radial direction on one side and the other side in the radial direction with the accommodation hole interposed therebetween, The accommodation hole is formed surrounded by a first side surface facing each other in the radial direction and a second side surface facing each other in the circumferential direction, The magnet is composed of two divided magnets arranged in the circumferential direction in the accommodation hole, The two divided magnets are offset so as to be close to the first side surface on the side where the core thickness in the radial direction is thick among both sides in the radial direction of the accommodation hole in the radial direction, and are offset so as to be close to the second side surface in the circumferential direction, In the accommodation hole, the filling agent is filled in a separation portion between the magnet and the rotor core formed by the offset of each divided magnet in the radial direction and the circumferential direction.

[0009] In the rotor with the above configuration, two split magnets arranged in the circumferential direction are accommodated in the accommodation holes of the rotor core. Further, in the rotor core, the core thickness is different between one side and the other side in the radial direction with the accommodation hole interposed therebetween. In this case, each split magnet is configured such that the variation in position within the accommodation hole is suppressed by the magnetic force of the magnet itself. Specifically, since the core thickness is different between the inner and outer sides in the radial direction with the accommodation hole interposed in the rotor core, each split magnet is offset so as to be close to the first side surface on the side where the core thickness is thick in the radial direction. Further, since a magnetic repulsive force is generated between the split magnets in the accommodation hole, each split magnet is offset so as to be close to the second side surface on the opposite side in the circumferential direction. Further, since the accommodation hole is filled with a filler, the offset state of each split magnet is maintained. In this configuration, since the variation in the position of each split magnet is suppressed by utilizing the magnetic force of the magnet itself, for example, the complexity during manufacturing can be suppressed as compared with a configuration using a plurality of types of adhesives. As a result, the magnet can be properly fixed in the accommodation hole of the rotor core.

[0010] In means 2, in means 1, each of the split magnets is divided into two in the axial direction, and in the accommodation hole, the split magnets arranged in the axial direction are separated from each other, and the filler is filled in the separated portion.

[0011] In the configuration in which each split magnet is divided into two in the axial direction, a magnetic repulsive force is generated between the magnets divided in the axial direction. Therefore, in addition to the radial direction and the circumferential direction in the accommodation hole of the rotor core, the variation in the position of each split magnet can be suppressed also in the axial direction.

[0012] In means 3, in means 1 or 2, in the two split magnets, the radial thickness dimension on the side of the d-axis which is the magnetic pole center is larger than the radial thickness dimension on the side of the q-axis which is the magnetic pole boundary.

[0013] Since each of the divided magnets in the accommodation hole has a larger radial thickness dimension on the d-axis side than on the q-axis side, the magnetic repulsive force in the circumferential direction between the divided magnets can be increased, and the circumferential position variation can be more appropriately suppressed. Further, according to the above configuration, the effect of magnetic flux strengthening on the d-axis can be expected for each magnetic pole of the rotor.

[0014] The means 4 is comprising a rotor core made of a soft magnetic material and a plurality of magnets respectively accommodated in a plurality of accommodation holes provided at predetermined intervals in the circumferential direction in the rotor core, the rotor core has different core thicknesses in the radial direction on one side and the other side in the radial direction with the accommodation hole interposed therebetween, The accommodation hole is formed to be surrounded by a first side surface facing each other in the radial direction and a second side surface facing each other in the circumferential direction. A manufacturing method of a rotor, an insertion step of filling a non-cured filler into the accommodation hole and inserting two divided magnets in a state of being arranged in the circumferential direction in the accommodation hole as the magnet; a shifting step of shifting each of the divided magnets so as to be close to the first side surface on the side having a thicker core thickness in the radial direction of both sides in the radial direction of the accommodation hole by the magnetic force of each of the divided magnets after the insertion step, and shifting each of the divided magnets so as to be close to the second side surface in the circumferential direction; a fixing step of curing the filler in the accommodation hole to fix each of the divided magnets after the shifting step; characterized by having the above.

[0015] According to the above manufacturing method, while the filler in an uncured state is filled in the accommodation hole and the two split magnets arranged in the circumferential direction are inserted, the displacement arrangement due to the magnetic force of each split magnet is performed. In this case, each split magnet is displaced so as to approach the first side surface on the thicker side of the core thickness in the radial direction among both sides in the radial direction of the accommodation hole by the magnetic force of the magnet itself. Further, since a magnetic repulsive force is generated between the split magnets, each split magnet is displaced so as to approach the second side surface on the opposite side in the circumferential direction. Then, after each split magnet is displaced, the filler is cured to fix each split magnet. As a result, the variation in the position of each split magnet in the accommodation hole is suppressed. In this manufacturing method, since the variation in the position of each split magnet is suppressed by utilizing the magnetic force of the magnet itself, for example, the complexity during manufacturing can be suppressed as compared with a method using a plurality of types of adhesives. As a result, the magnet can be properly fixed in the accommodation hole of the rotor core.

[0016] In means 5, in means 4, in the insertion step, each of the split magnets in a non-magnetized state is inserted into the accommodation hole, and in the displacement step, magnetization is performed on each of the split magnets in a non-magnetized state in the accommodation hole using a magnetization device, and due to the magnetic force of the magnet after the magnetization, displacement of each of the split magnets in the radial direction and the circumferential direction is caused in the accommodation hole.

[0017] In the displacement step, magnetization of each of the split magnets in a non-magnetized state inserted into the accommodation hole is performed by a magnetization device, and due to the magnetic force of the magnet after the magnetization, displacement of each of the split magnets in the radial direction and the circumferential direction is caused in the accommodation hole. In this case, by continuously performing the magnetization and positioning of each split magnet, the rotor can be efficiently manufactured.

[0018] In means 6, in means 4 or 5, in the insertion step, as the magnet, the split magnet divided into two in the circumferential direction and the axial direction respectively is inserted into the accommodation hole, and in the shifting step, due to the magnetic force of each split magnet, the split magnet is shifted in the radial direction and the circumferential direction in the accommodation hole, and the split magnets arranged in the axial direction are arranged in a state of being separated from each other.

[0019] In the shifting step, using the magnetic repulsive force between the magnets axially divided into two, the axial positioning of each magnet is performed. Thereby, in addition to the radial direction and the circumferential direction in the accommodation hole of the rotor core, the variation in the position of each split magnet can be suppressed also in the axial direction.

[0020] Means 7 is comprised of a rotor core made of a soft magnetic material and a plurality of magnets respectively accommodated in a plurality of accommodation holes provided at predetermined intervals in the circumferential direction in the rotor core, the rotor core has different core thicknesses in the radial direction on one side and the other side in the radial direction with the accommodation hole interposed therebetween, the accommodation hole is surrounded by a first side surface facing each other in the radial direction and a second side surface facing each other in the circumferential direction, and is a method for manufacturing a rotor, an insertion step of filling a non-cured filler into the accommodation hole and inserting the magnet, after the insertion step, due to the magnetic force of the magnet, the magnet is shifted so as to be close to the first side surface on the side where the core thickness in the radial direction is thick among both sides in the radial direction of the accommodation hole, and due to an external magnetic force facing one side in the circumferential direction, the magnet is shifted so as to be close to one side of the second side surfaces on both sides in the circumferential direction, a shifting step, a fixing step of curing the filler in the accommodation hole to fix the magnet after the shifting step, characterized by having.

[0021] According to the above manufacturing method, the magnet is offset while the filler in a non-cured state is filled and the magnet is inserted in the accommodation hole. In this case, the magnet is offset so as to approach the first side surface on the side where the core thickness in the radial direction is thicker among both sides in the radial direction of the accommodation hole by the magnetic force of the magnet itself. Further, by applying an external magnetic force directed to one side in the circumferential direction to the magnet in the accommodation hole, the magnet is offset so as to approach one side of the second side surfaces on both sides in the circumferential direction. Then, after the magnet is offset, the filler is cured to fix the magnet. As a result, the variation in the position of the magnet in the accommodation hole is suppressed. In this manufacturing method, since the variation in the position of the magnet is suppressed by using the magnetic force of the magnet itself and the external magnetic force, for example, the complexity during manufacturing can be suppressed as compared with a method using a plurality of types of adhesives. As a result, the magnet can be properly fixed in the accommodation hole of the rotor core.

[0022] In means 8, in means 7, in the insertion step, the magnet in a non-magnetized state is inserted into the accommodation hole, and in the offset step, magnetization is performed on the magnet in the non-magnetized state in the accommodation hole using a magnetization device that generates a magnetization magnetic field, and the magnet is offset so as to approach one side of the second side surfaces on both sides in the circumferential direction using an offset magnetic force device that generates an external magnetic force directed to one side in the circumferential direction.

[0023] In the offset step, magnetization of the magnet in the non-magnetized state inserted into the accommodation hole is performed by a magnetization device, and the magnet is offset so as to approach one side of the second side surfaces on both sides in the circumferential direction by the external magnetic force of the offset magnetic force device. In this case, by continuously performing magnetization and positioning of the magnet, the rotor can be efficiently manufactured.

[0024] Means 9 is composed of a rotor core made of a soft magnetic material and a plurality of magnets respectively accommodated in a plurality of accommodation holes provided at predetermined intervals in the circumferential direction in the rotor core, the rotor core has different core thicknesses in the radial direction on one side and the other side in the radial direction with the accommodation hole interposed therebetween, The accommodating hole is surrounded by a first side surface facing each other in the radial direction and a second side surface facing each other in the circumferential direction, and is a rotor of a rotating electrical machine formed thereby. The magnet is composed of two split magnets arranged in the circumferential direction within the accommodating hole. The two split magnets are offset so as to be close to the first side surface on the side where the core thickness in the radial direction is thick among both sides in the radial direction of the accommodating hole in the radial direction, and are offset so as to be close to the second side surface in the circumferential direction, respectively.

[0025] In the rotor having the above configuration, since the core thickness is different inside and outside in the radial direction across the accommodating hole in the rotor core, each split magnet is offset so as to be close to the first side surface on the side where the core thickness is thick in the radial direction. Further, since a magnetic repulsive force is generated between the split magnets in the accommodating hole, each split magnet is offset so as to be close to the second side surface on the opposite side in the circumferential direction. In this configuration, the positional variation of each split magnet is suppressed by utilizing the magnetic force of the magnet itself, so that, for example, the complexity during manufacturing can be suppressed as compared with a configuration using a plurality of types of adhesives. As a result, the magnet can be properly fixed in the accommodating hole of the rotor core.

Brief Description of the Drawings

[0026]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Mode for Carrying Out the Invention

[0027] Hereinafter, embodiments will be described with reference to the drawings. The rotating electrical machine in the present embodiment is, for example, used as an in-vehicle electric device. However, the rotating electrical machine can be widely used as an industrial, marine, aircraft, household electric appliance, OA equipment, gaming machine, etc. In addition, in each of the following embodiments, parts that are the same or equivalent to each other are denoted by the same reference numerals in the drawings, and the description of the parts with the same reference numerals is incorporated by reference.

[0028] (First Embodiment) The rotating electrical machine 10 according to the present embodiment is an inner rotor type (internal rotation type) polyphase AC motor, and its outline is shown in FIGS. 1 and 2. FIG. 1 is a longitudinal sectional view showing a longitudinal section in the direction along the rotating shaft 11 of the rotating electrical machine 10, and FIG. 2 is a cross-sectional view showing a cross section of the rotor 12 and the stator 13 in the direction orthogonal to the rotating shaft 11. In the following description, the direction in which the rotating shaft 11 extends is defined as the axial direction, the direction extending radially around the rotating shaft 11 is defined as the radial direction, and the direction extending circumferentially around the rotating shaft 11 is defined as the circumferential direction.

[0029] The rotating electrical machine 10 includes a rotor 12 fixed to a rotating shaft 11, a stator 13 provided at a position surrounding the rotor 12, and a housing 14 that houses the rotor 12 and the stator 13. The rotor 12 and the stator 13 are coaxially arranged. The housing 14 has a pair of housing members 14a and 14b having a bottomed cylindrical shape, and the housing members 14a and 14b are integrated by fastening bolts 15 in a state where the openings are joined to each other. Bearings 16 and 17 are provided in the housing 14, and the rotating shaft 11 and the rotor 12 are rotatably supported by these bearings 16 and 17.

[0030] As shown in FIG. 2, the rotor 12 is configured as an embedded magnet type rotor (IPM rotor), and includes a rotor core 21 that rotates integrally with the rotating shaft 11, and a plurality of permanent magnets 22 held by the rotor core 21. The rotor core 21 is made of a soft magnetic material and is configured by laminating a plurality of electromagnetic steel sheets in the axial direction and fixing them by caulking or the like. A plurality of accommodation holes 23 are provided in the rotor core 21 at predetermined intervals in the circumferential direction, and the permanent magnets 22 are respectively accommodated in the accommodation holes 23. Thereby, the permanent magnets 22 are arranged side by side in the circumferential direction for each magnetic pole. In the present embodiment, the rotor 12 is provided with 10 poles (5 pole pairs) such that N poles and S poles are alternately arranged in the circumferential direction. However, the number of poles is arbitrary.

[0031] The stator 13 includes an annular stator core 32 having a plurality of slots 31 in the circumferential direction, and three-phase (U-phase, V-phase, W-phase) stator windings 33 wound around each slot 31 of the stator core 32. The stator core 32 is configured by laminating a plurality of annular electromagnetic steel sheets in the axial direction and fixing them by caulking or the like. The stator core 32 has an annular yoke 34 and a plurality of teeth 35 protruding radially inward from the yoke 34 and arranged at a predetermined distance in the circumferential direction, and slots 31 are formed between adjacent teeth 35. Each tooth 35 is provided at equal intervals in the circumferential direction.

[0032] In each slot 31, a stator winding 33 is wound around teeth 35 and fixed. The stator winding 33 is configured by using a conductor 36 made of a flat conductor wire, and the conductor 36 is accommodated in each slot 31 in a state of being radially arranged in a plurality of layers. More specifically, the stator winding 33 is configured by joining a plurality of conductor segments to each other. Note that in the stator core 32, the conductors 36 having the same phase with a logarithm of 2 for each magnetic pole are arranged side by side in the circumferential direction.

[0033] By the way, on the rotor core 21 of the rotor 12, an accommodation hole 23 is provided with a dimension larger than that of the permanent magnet 22 for reasons such as convenience in work. When the permanent magnet 22 is accommodated in the accommodation hole 23, an excess gap is formed between the outer peripheral surface of the permanent magnet 22 and the inner wall of the accommodation hole 23. Therefore, there is a concern about the variation in the position of the permanent magnet 22 in the accommodation hole 23. Thus, in the present embodiment, in the rotor 12, the variation in the position of the permanent magnet 22 in the accommodation hole 23 is suppressed by using the magnetic force of the magnet itself. The detailed configuration thereof will be described below.

[0034] FIG. 3 is a cross-sectional view showing an enlarged configuration of the magnetic poles of the rotor 12. (a) shows the accommodation hole 23 in a state where the permanent magnet 22 is not accommodated, and (b) shows a state where the permanent magnet 22 is accommodated in the accommodation hole 23.

[0035] As shown in FIG. 3(a), in the rotor core 21, the accommodation holes 23 are formed for each magnetic pole so as to extend linearly between two q - axes which are the magnetic pole boundaries with the d - axis, which is the center of the magnetic pole, as the center in the circumferential direction. The accommodation hole 23 extends in a direction orthogonal to the d - axis and is formed surrounded by a pair of first side surfaces 23a and 23b facing each other in the radial direction and a pair of second side surfaces 23c and 23d facing each other in the circumferential direction. In the first side surface 23a on the radially inner side of the pair of first side surfaces 23a and 23b, recesses 23e are formed at both ends in the circumferential direction. Further, in the pair of second side surfaces 23c and 23d, recesses 23f are formed so as to bulge outward in the circumferential direction.

[0036] The accommodation hole 23 is provided near the outer peripheral portion of the rotor core 21, and the core thickness in the radial direction is different between one side and the other side in the radial direction with the accommodation hole 23 interposed therebetween. Specifically, the core thickness on the inner side in the radial direction is thicker than the core thickness on the outer side in the radial direction.

[0037] As shown in FIG. 3(b), in the accommodation hole 23, two divided magnets 22a and 22b are accommodated in a state of being arranged in the circumferential direction, and these divided magnets 22a and 22b are fixed by a filling agent 24 filled in the accommodation hole 23. The filling agent 24 is, for example, an adhesive. The divided magnets 22a and 22b have a rectangular cross section, and the direction of magnetic force lines inside the magnets is parallel or substantially parallel to the d-axis.

[0038] Here, in each of the divided magnets 22a and 22b accommodated in the accommodation hole 23, a force is generated in the direction indicated by the arrow in FIG. 4 due to the magnetic force of the magnet itself, and the positioning of each of the divided magnets 22a and 22b is performed by this force. Specifically, the two divided magnets 22a and 22b are arranged in a state of being shifted so as to be close to the first side surface 23a on the inner side in the radial direction among both sides in the radial direction of the accommodation hole 23 by the magnetic attraction force F1 generated inward in the radial direction. That is, the core thickness is different on both sides in the radial direction of the accommodation hole 23, and since the core thickness is thicker on the inner side in the radial direction, a strong magnetic attraction force F1 is generated inward in the radial direction. As a result, each of the divided magnets 22a and 22b is arranged so as to be close to the side with the thicker core thickness, that is, the first side surface 23a on the inner side in the radial direction.

[0039] Further, the two split magnets 22a and 22b are arranged in a state of being offset so as to approach the second side surfaces 23c and 23d, respectively, due to the magnetic repulsive force F2 and the magnetic attractive force F3 generated in the circumferential direction. That is, in the rotor core 21, the split magnets 22a and 22b of the same polarity are accommodated in one accommodation hole 23, and the split magnets 22a and 22b of different polarities are respectively accommodated in the adjacent accommodation holes 23 in the circumferential direction. For example, if the central magnetic pole in Fig. 3(b) is the N pole, the polarities of the magnetic poles on both sides thereof are the S poles. In this case, in the vicinity of the d-axis, a magnetic repulsive force F2 is generated in the circumferential direction between the split magnets 22a and 22b, while in the vicinity of the q-axis, a magnetic attractive force F3 is generated in the circumferential direction between the split magnet 22a or 22b and the adjacent magnetic pole. As a result, the split magnet 22a on the left side of the figure is offset so as to approach the left second side surface 23c, and the split magnet 22b on the right side of the figure is offset so as to approach the right second side surface 23d. Each of the split magnets 22a and 22b may be in contact with the first side surface 23a or the second side surfaces 23c and 23d.

[0040] And in the accommodation hole 23, the filler 24 is filled in the region formed by the offset in the radial direction and the circumferential direction of each of the split magnets 22a and 22b, that is, the separated portion between the permanent magnet 22 and the rotor core 21.

[0041] Next, a method for manufacturing the rotor 12 will be described. Fig. 5 is a flowchart showing the manufacturing procedure of the rotor 12.

[0042] When manufacturing the rotor 12, in the first step S11, an adhesive in a non-cured state (flexible state before curing) is applied as the filler 24 to either the split magnets 22a and 22b or the accommodation holes 23 of the rotor core 21. It is also possible to apply the adhesive to both the split magnets 22a and 22b and the accommodation holes 23 of the rotor core 21.

[0043] Also, in the second step S12, the unmagnetized split magnets 22a and 22b are inserted into the accommodation holes 23. The split magnets 22a and 22b prepared at this time are magnets in an unmagnetized state generated by synthesis, molding, sintering, etc. of magnet raw materials. Each of the split magnets 22a and 22b is inserted in a state of being arranged in the circumferential direction within the accommodation hole 23. The first step S11 and the second step S12 correspond to the "insertion step".

[0044] Thereafter, in the third step S13, magnetization of the split magnets 22a and 22b in the accommodation holes 23 and offset arrangement of the respective split magnets 22a and 22b in the accommodation holes 23 are performed. FIG. 6 is a diagram showing a magnetization device 40 for magnetizing the split magnets 22a and 22b. The magnetization device 40 is a device for magnetizing the split magnets 22a and 22b of each pole by an electromagnet, and includes a magnetization yoke 41 having an annular shape and a plurality of convex portions 42 on the radially inner side, and magnetization coils 43 wound around each of the convex portions 42. The convex portions 42 of the magnetization yoke 41 are provided in the same number and at the same pitch as the number of poles of the rotor 12.

[0045] The rotor 12 is disposed inside the magnetization yoke 41 in the radial direction. At this time, the rotor 12 is disposed such that the magnetic pole center (d-axis) of the rotor 12 coincides with the circumferential center position of the convex portion 42 of the magnetization yoke 41. Then, when current flows through each magnetization coil 43 by energization of a power supply unit (not shown), a magnetization magnetic field is generated for each convex portion 42. As a result, magnetization is performed on each of the split magnets 22a and 22b in the accommodation holes 23, and magnetic poles of different polarities are alternately formed in the circumferential direction on the rotor 12.

[0046] After magnetization of each of the divided magnets 22a and 22b, due to the magnetic force of the divided magnets 22a and 22b themselves, the divided magnets 22a and 22b are displaced in the radial and circumferential directions in the accommodation holes 23. At this time, the adhesive in the accommodation holes 23 is in a non-cured state, and the divided magnets 22a and 22b move within the accommodation holes 23 due to the magnetic force of the magnets themselves. Specifically, as described with reference to FIG. 4, due to the radially inward magnetic attraction force F1, the divided magnets 22a and 22b are displaced so as to approach the first side surface 23a on the inner side in the radial direction. Further, due to the circumferential magnetic repulsive force F2 and magnetic attraction force F3, the divided magnets 22a and 22b are displaced so as to approach the second side surfaces 23c and 23d, respectively.

[0047] When the divided magnets 22a and 22b are displaced in the accommodation holes 23, the adhesive between each of the divided magnets 22a and 22b and the first side surface 23a on the inner side in the radial direction is extruded, and each of the divided magnets 22a and 22b and the first side surface 23a come into a close state. Also, the adhesive between each of the divided magnets 22a and 22b and each of the second side surfaces 23c and 23d is extruded, and each of the divided magnets 22a and 22b and each of the second side surfaces 23c and 23d come into a close state. The third step S13 corresponds to the "displacement step".

[0048] Thereafter, in the fourth step S14, the adhesive in the accommodation holes 23 is cured to fix each of the divided magnets 22a and 22b. As a result, each of the divided magnets 22a and 22b is fixed at the same position in each of the circumferentially arranged accommodation holes 23. The fourth step S14 corresponds to the "fixing step".

[0049] According to the present embodiment described in detail above, the following excellent effects can be obtained.

[0050] In the rotor 12 having the above-described configuration, since the variation in the positions of the divided magnets 22a and 22b is suppressed by using the magnetic force of the magnets themselves, for example, the complexity during manufacturing can be suppressed as compared with a configuration using a plurality of types of adhesives. As a result, the permanent magnets 22 can be properly fixed in the accommodation holes 23 of the rotor core 21. And by suppressing the variation in the magnet positions, the deterioration of the characteristics of the rotating electrical machine 10 can be suppressed.

[0051] Further, according to the above manufacturing method, by determining the magnet position using the magnetic force of the magnet itself, the rotor 12 with no variation in the position of the permanent magnet 22 can be suitably manufactured. Also, by continuously magnetizing and positioning each of the split magnets 22a and 22b, the rotor 12 can be manufactured efficiently.

[0052] As a modification of the first embodiment, the following configuration can also be adopted.

[0053] · As shown in FIG. 7, the rotor core 21 may be provided with a connecting portion 25 extending in the radial direction at the circumferential center position (d-axis position) of the accommodation hole 23 in each magnetic pole. That is, the accommodation hole 23 of each magnetic pole is divided into two in the circumferential direction by the connecting portion 25, and the split magnets 22a and 22b are accommodated in each of the divided holes one by one. Also in this configuration, similarly to the above, the two split magnets 22a and 22b are shifted so as to approach the first side surface 23a on the inner side in the radial direction by the magnetic attraction force generated in the radial inward direction, and are shifted so as to approach the second side surfaces 23c and 23d respectively by the magnetic repulsive force and the magnetic attraction force generated in the circumferential direction.

[0054] According to the configuration of FIG. 7, in addition to being able to suppress the variation in the magnet position in the accommodation hole 23 as described above, the centrifugal strength of the rotor 12 can be improved by providing the connecting portion 25.

[0055] · As shown in Fig. 8, within the accommodation hole 23, each of the divided magnets 22a and 22b may be axially divided into two parts. In the rotor 12 shown in Fig. 8, in its longitudinal section, magnets 26 and 27 divided into two upper and lower parts as the divided magnets 22a and 22b are shown. In this case, an axial magnetic repulsive force is generated between the magnets 26 and 27 arranged axially, so that the magnets 26 and 27 are separated from each other axially. And the filler 24 is filled in the separated portion. The total axial length of each of the divided magnets 22a and 22b (the length obtained by adding the lengths of the magnets 26 and 27) may be shorter than the axial length of the rotor core 21. Plates 28 for closing the openings of the accommodation holes 23 are provided at both axial ends of the rotor core 21, and the plates 28 regulate the protrusion of the magnets 26 and 27 from the accommodation holes 23.

[0056] During the manufacture of the rotor 12, in the second step S12 of Fig. 5, the divided magnets 22a and 22b divided circumferentially and axially are inserted into the accommodation hole 23. That is, in this case, four magnet pieces are inserted for each accommodation hole 23. Then, in the third step S13, magnetization of each of the divided magnets 22a and 22b is performed, and after the magnetization, due to the magnetic force of the magnets, the divided magnets 22a and 22b are offset in the radial and circumferential directions in the accommodation hole 23, and the magnets 26 and 27 arranged axially are arranged in a state of being separated from each other. At this time, plates 28 are attached to both axial ends of the rotor core 21 so as to close the openings of the accommodation holes 23, and in this state, by generating an axial magnetic repulsive force, the magnets 26 and 27 may be brought into contact with the plates 28.

[0057] Then, in the fourth step S14, the adhesive in the accommodation hole 23 is cured to fix each of the divided magnets 22a and 22b.

[0058] Note that instead of regulating the axial positions of the magnets 26 and 27 by the plates 28, it is also possible to regulate the axial positions of the magnets 26 and 27 by a working jig. In this case, after the positions of the magnets 26 and 27 are determined as the adhesive cures, the jig may be removed.

[0059] According to the above configuration, in addition to the radial and circumferential directions in the accommodation hole 23 of the rotor core 21, it is possible to suppress the positional variation of each divided magnet 22a, 22b also in the axial direction.

[0060] · As shown in FIG. 9, in each of the divided magnets 22a, 22b, the radial thickness dimension on the d-axis side may be larger than the radial thickness dimension on the q-axis side. In the illustrated configuration, among the side surfaces on both radial sides of each divided magnet 22a, 22b, the radially inner side surface is provided to be inclined obliquely with respect to the direction orthogonal to the d-axis, thereby increasing the radial thickness dimension on the d-axis side. Regarding the first side surfaces 23a, 23b of the accommodation hole 23, the radially outer first side surface 23b is provided in the direction orthogonal to the d-axis, while the radially inner first side surface 23a is symmetric on both sides across the d-axis and is provided obliquely with respect to the direction orthogonal to the d-axis.

[0061] In this case, the circumferential magnetic repulsive force between the divided magnets 22a, 22b can be increased, and the circumferential positional variation can be suppressed more appropriately. Further, according to the above configuration, the effect of magnetic flux enhancement on the d-axis can be expected at each magnetic pole of the rotor 12.

[0062] · It is also possible to use a resin material instead of the adhesive as the filler 24. In this case, in the first step S11 of FIG. 5, the non-magnetized divided magnets 22a, 22b are inserted into the accommodation hole 23. Further, in the second step S12, a resin material in a non-cured state (liquid state before curing) is poured into the gap portion of the accommodation hole 23 in a state where the divided magnets 22a, 22b are accommodated as the filler 24. Then, after performing magnetization and offset arrangement in the third step S13, in the fourth step S14, the resin material in the accommodation hole 23 is cured to fix each divided magnet 22a, 22b.

[0063] · The magnetization device 50 may generate a magnetization magnetic field by a permanent magnet in addition to generating a magnetization magnetic field by an electromagnet.

[0064] · In the above-described embodiment, in the second step S12 of FIG. 5, the split magnets 22a and 22b in the demagnetized state are inserted into the accommodation holes 23, and in the subsequent third step S13, magnetization of the split magnets 22a and 22b in the accommodation holes 23 is performed. However, this can be changed, and in the second step S12, the magnetized split magnets 22a and 22b may be inserted into the accommodation holes 23. In this case, in the third step S13, the split magnets 22a and 22b are not magnetized, and only the offset arrangement of each split magnet 22a and 22b is performed.

[0065] Hereinafter, an embodiment different from the first embodiment will be described focusing on the differences from the first embodiment.

[0066] (Second Embodiment) In this embodiment, as a modification from the first embodiment, a configuration is adopted in which a single permanent magnet 22 is accommodated in each accommodation hole 23 of the rotor core 21. FIG. 10 is a cross-sectional view showing an enlarged configuration of the magnetic poles of the rotor 12. The configuration of the accommodation hole 23 is the same as the configuration shown in FIG. 3 and the like.

[0067] In FIG. 10, a single permanent magnet 22 is accommodated in the accommodation hole 23, and the permanent magnet 22 is fixed by a filler 24. The filler 24 is, for example, an adhesive. However, the filler 24 may be a resin material. The permanent magnet 22 has a rectangular cross-section, and the direction of the magnetic field lines inside the magnet is parallel or substantially parallel to the d-axis. The permanent magnet 22 is offset in the accommodation hole 23 so as to be close to the first side surface 23a on the inner side in the radial direction among both sides in the radial direction, and is also offset so as to be close to the second side surface 23c on one side among both sides in the circumferential direction, and is arranged in this state. The permanent magnet 22 may be in contact with the first side surface 23a or the second side surface 23c. Then, in the accommodation hole 23, the region formed by the offset of the permanent magnet 22 in the radial direction and the circumferential direction, that is, the separation portion between the permanent magnet 22 and the rotor core 21, is filled with the filler 24.

[0068] Next, a method for manufacturing the rotor 12 will be described. FIG. 11 is a flowchart showing the manufacturing procedure of the rotor 12.

[0069] When manufacturing the rotor 12, in the first step S21, an uncured adhesive is applied as the filler 24 to either the permanent magnet 22 or the accommodation hole 23 of the rotor core 21. Further, in the second step S22, the non-magnetized permanent magnet 22 is inserted into the accommodation hole 23. These steps S21 and S22 generally correspond to the steps S11 and S12 in FIG. 5 described above, except that the configuration of the permanent magnet 22 is different.

[0070] Thereafter, in the third step S23, magnetization of the permanent magnet 22 in the accommodation hole 23 is performed using a magnetization device 40 (see FIG. 6). At this time, as shown in FIG. 12(a), the rotor 12 is arranged such that the magnetic pole center (d-axis) of the rotor 12 coincides with the circumferential center position of the convex portion 42 of the magnetization yoke 41, and magnetization is performed by the magnetization magnetic field generated by energizing each magnetization coil 43. In this third step S23, due to the magnetic force of the magnet after magnetization, the permanent magnet 22 is shifted so as to be close to the first side surface 23a on the inner side in the radial direction among both sides in the radial direction of the accommodation hole 23.

[0071] Further, in the fourth step S24, displacement arrangement of the permanent magnet 22 in the circumferential direction is performed in the accommodation hole 23 by the external magnetic force generated from the magnetization device 40. At this time, as shown in FIG. 12(b), the rotor 12 is arranged such that the magnetic pole boundary (q-axis) of the rotor 12 coincides with the circumferential center position of the convex portion 42 of the magnetization yoke 41, and displacement arrangement of the permanent magnet 22 is performed by the displacement magnetic field generated by energizing each magnetization coil 43. The external magnetic force generated from the magnetization device 40 is a magnetic force directed toward one side in the circumferential direction (left direction in FIG. 12(b)), and due to this external magnetic force, the permanent magnet 22 is shifted so as to be close to one second side surface 23c in the circumferential direction. The third step S23 and the fourth step S24 correspond to the "shifting step".

[0072] Note that in the fourth step S24, the magnetization device 40 corresponds to a "bias magnetic force device". In the third step S23 and the fourth step S24, the magnitude of the generated magnetic force by the magnetization device 40 may be made different. Also, when shifting the permanent magnet 22, it is also possible to generate an external magnetic force using a magnetic force generating device (bias magnetic force device) different from the magnetization device used for magnetizing the permanent magnet 22.

[0073] Thereafter, in the fifth step S25, the adhesive in the accommodation hole 23 is cured to fix the permanent magnet 22. As a result, the permanent magnets 22 are fixed at the same position in each of the accommodation holes 23 arranged in the circumferential direction. The fifth step S25 corresponds to the "fixing step".

[0074] According to the above manufacturing method, since the variation in the position of the permanent magnet 22 is suppressed by utilizing the magnetic force of the magnet itself and the external magnetic force, for example, the complexity during manufacturing can be suppressed compared to a method using a plurality of types of adhesives. As a result, the permanent magnet 22 can be properly fixed in the accommodation hole 23 of the rotor core 21.

[0075] In the shifting step, the non-magnetized permanent magnet 22 inserted into the accommodation hole 23 is magnetized by the magnetization device 50, and the permanent magnet 22 is shifted so as to approach one side of the second side surfaces 23c on both sides in the circumferential direction by the external magnetic force of the bias magnetic force device. In this case, by continuously performing the magnetization and positioning of the permanent magnet 22, the rotor 12 can be efficiently manufactured.

[0076] (Other embodiments) The above embodiment may be modified as follows, for example.

[0077] · In the configuration shown in Fig. 3(b), in the accommodation hole 23, the filler 24 was filled in the separation portion between the permanent magnet 22 and the rotor core 21 formed by the displacement of the divided magnets 22a and 22b in the radial direction and the circumferential direction. However, it may be configured such that the filler 24 is not filled. In this case, the rotor 12 has the following configuration. That is, in the accommodation hole 23 of each magnetic pole, the divided magnets 22a and 22b are accommodated in a state of being arranged side by side in the circumferential direction. More specifically, in the radial direction, they are displaced so as to be close to the first side surface on the thicker side of the core thickness in the radial direction on both sides in the radial direction of the accommodation hole 23, and in the circumferential direction, they are displaced so as to be close to the second side surfaces 23c and 23d, respectively.

[0078] In the rotor 12 of this configuration, similar to the above-described embodiment, it is possible to suppress the positional variation of each of the divided magnets 22a and 22b by utilizing the magnetic force of the magnet itself. Further, since a filler such as an adhesive or a resin material is not required, it is possible to reduce the manufacturing cost of the rotor 12. In addition, even in a state where torque is generated by the winding electromagnetic force of the stator 13 during the use of the rotating electrical machine 10, the magnetic attractive force and the magnetic repulsive force at each of the divided magnets 22a and 22b are maintained, and the state of the displaced arrangement of each of the divided magnets 22a and 22b is maintained.

[0079] · In each of the above embodiments, an application example in a rotating electrical machine having an inner rotor type IPM rotor has been described. However, it is also possible to apply it to a rotating electrical machine having an outer rotor type IPM rotor.

Description of Reference Numerals

[0080] 12... Rotor, 21... Rotor core, 22... Permanent magnet, 22a, 22b... Divided magnets, 23... Accommodation hole, 23a, 23b... First side surfaces, 23c, 23d... Second side surfaces, 24... Filler.

Claims

1. A rotor (12) of a rotating electrical machine, comprising a rotor core (21) made of a soft magnetic material and a plurality of magnets (22) respectively accommodated in a plurality of accommodation holes (23) provided at predetermined intervals in the circumferential direction in the rotor core, wherein the magnets are fixed by a filling agent (24) filled in the accommodation holes, the rotor core has different core thicknesses in the radial direction on one side and the other side in the radial direction with the accommodation hole interposed therebetween, the accommodation hole is formed surrounded by first side surfaces (23a, 23b) facing each other in the radial direction and second side surfaces (23c, 23d) facing each other in the circumferential direction, the magnet is composed of two split magnets (22a, 22b) arranged in the circumferential direction in the accommodation hole, the two split magnets are offset so as to be close to the first side surface on the side where the core thickness in the radial direction is thick among both sides in the radial direction of the accommodation hole in the radial direction, and are offset so as to be close to the second side surface on the opposite side of each other's split magnets in the circumferential direction, in the accommodation hole, the filling agent is filled in a separation portion between the magnet and the rotor core formed by the offset of each split magnet in the radial direction and the circumferential direction. The rotor of the rotating electrical machine.

2. each of the split magnets is axially divided into two, in the accommodation hole, the split magnets arranged in the axial direction are separated from each other, and the separation portion is filled with the filling agent. The rotor of the rotating electrical machine according to claim 1.

3. In the two split magnets, the radial thickness dimension on the d-axis side, which is the magnetic pole center, is larger than the radial thickness dimension on the q-axis side, which is the magnetic pole boundary. The rotor of the rotating electrical machine according to claim 1 or 2.

4. A rotor (12) of a rotating electrical machine, comprising a rotor core (21) made of a soft magnetic material and a plurality of magnets (22) respectively accommodated in a plurality of accommodation holes (23) provided at predetermined intervals in the circumferential direction in the rotor core, The rotor core has different core thicknesses in the radial direction on one side and the other side of the accommodation hole in the radial direction with the accommodation hole interposed therebetween. A method for manufacturing a rotor (12) in which the accommodation hole is formed surrounded by a first side surface (23a, 23b) facing each other in the radial direction and a second side surface (23c, 23d) facing each other in the circumferential direction. An insertion step of filling a non-cured filler into the accommodation hole and inserting two split magnets (22a, 22b) as the magnets in a state of being arranged in the circumferential direction within the accommodation hole. After the insertion step, a shifting step of shifting each split magnet so as to approach the first side surface on the side where the core thickness in the radial direction is thick among both sides in the radial direction of the accommodation hole by the magnetic force of each split magnet, and also shifting each split magnet so as to approach the second side surface on the opposite side of each other's split magnets in the circumferential direction. A fixing step of curing the filler in the accommodation hole to fix each split magnet after the shifting step. A method for manufacturing a rotor having the above steps.

5. In the insertion step, each split magnet in a non-magnetized state is inserted into the accommodation hole. In the shifting step, magnetization is performed on each split magnet in a non-magnetized state in the accommodation hole using a magnetization device (40), and the split magnets are shifted in the radial and circumferential directions in the accommodation hole by the magnetic force of the magnet after magnetization. The method for manufacturing a rotor according to claim 4.

6. In the insertion step, the split magnet divided into two in the circumferential direction and the axial direction respectively is inserted into the accommodation hole as the magnet. In the shifting step, the split magnets are shifted in the radial and circumferential directions in the accommodation hole by the magnetic force of each split magnet, and the split magnets arranged in the axial direction are arranged in a state of being separated from each other. The method for manufacturing a rotor according to claim 4 or 5.

7. A rotor core (21) made of a soft magnetic material, and a plurality of magnets (22) respectively accommodated in a plurality of accommodation holes (23) provided at predetermined intervals in the circumferential direction in the rotor core. The rotor core has different core thicknesses in the radial direction on one side and the other side in the radial direction with the accommodation hole interposed therebetween. A method for manufacturing a rotor (12) in which the accommodation hole is formed surrounded by a first side surface (23a, 23b) facing each other in the radial direction and a second side surface (23c, 23d) facing each other in the circumferential direction. An insertion step of filling a non-cured filler into the accommodation hole and inserting the magnet. After the insertion step, the magnet is shifted so as to approach the first side surface on the side where the core thickness in the radial direction is thick among both sides in the radial direction of the accommodation hole by the magnetic force of the magnet, and the magnet is shifted so as to approach one side of the second side surfaces on both sides in the circumferential direction by an external magnetic force facing one side in the circumferential direction. A shifting step. After the shifting step, a fixing step of curing the filler in the accommodation hole to fix the magnet. A method for manufacturing a rotor having the above.

8. In the insertion step, the magnet in a non-magnetized state is inserted into the accommodation hole. In the shifting step, magnetization is performed on the magnet in a non-magnetized state in the accommodation hole using a magnetization device (50) that generates a magnetization magnetic field, and the magnet is shifted so as to approach one side of the second side surfaces on both sides in the circumferential direction using a shifting magnetic force device (50) that generates an external magnetic force facing one side in the circumferential direction. The method for manufacturing a rotor according to claim 7.

9. A rotor core (21) made of a soft magnetic material, and a plurality of magnets (22) respectively accommodated in a plurality of accommodation holes (23) provided at predetermined intervals in the circumferential direction in the rotor core. The rotor core has different core thicknesses in the radial direction on one side and the other side in the radial direction with the accommodation hole interposed therebetween. The rotor (12) of a rotating electrical machine, in which the accommodation hole is formed surrounded by a first side surface (23a, 23b) facing each other in the radial direction and a second side surface (23c, 23d) facing each other in the circumferential direction, The magnet is composed of two divided magnets (22a, 22b) arranged in the circumferential direction within the accommodation hole, The two divided magnets are shifted so as to be close to the first side surface on the side where the core thickness in the radial direction is thick among both sides in the radial direction of the accommodation hole in the radial direction, and are shifted so as to be close to the second side surface on the opposite side of each other's divided magnets in the circumferential direction. The rotor of a rotating electrical machine.

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