Rotating electric machines

Abstract

To provide a rotary electric machine capable of surely being fixed to a rotor core while suppressing damages of a magnet.SOLUTION: A rotary electric machine comprises: a rotor 10 which is rotatable around a center shaft; and a stator which is positioned on a radial direction outer side of the rotor 10. The rotor 10 includes: a rotor core 20 in which a plurality of magnetic steel sheets 25 are laminated in the shaft direction where the center shaft is extended and which has a plurality of housing holes 30; and a plurality of magnets 40 that are housed in each of inner parts of the plurality of housing holes 30. The rotor core 20 includes: a first concave part 80 that is concaved from a first core end surface 20a on one side of the shaft direction to the other side of the shaft direction; a first caulking part 82 that is provided to a bottom surface of the first concave part 80; and a first projection part 84 that is projected to each magnet 40 side in the direction where an inner peripheral edge of each housing hole 30 crosses the shaft direction, and hits against a side surface 40t of each magnet 40.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a rotating electric machine. [Background technology]

[0002] A rotating electric machine is known that includes a rotor core and magnets arranged in holes provided in the rotor core. For example, Patent Document 1 describes a magnet-embedded rotor in which the ends of the magnets inserted into the holes provided in the rotor core are held and fixed to the rotor core by crimping the steel plates located at the ends of the laminated steel plates that make up the yoke of the rotor core. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-64951 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-described configuration, due to manufacturing tolerances and other reasons, the dimensions of the laminated steel plates may be larger than the dimensions of the magnets in the central axis direction of the rotor core. In such cases, when the steel plates located at the ends of the laminated steel plates in the central axis direction are crimped, the portions that protrude in a direction intersecting the central axis direction may not contact the magnets or may abut against the ends of the magnets in the central axis direction. If the crimped steel plates do not contact the magnets, the magnets cannot be fixed. Furthermore, if the crimped steel plates abut against the ends of the magnets, the magnets may be damaged. Thus, the above-described configuration has the problem of making it difficult to securely fix the magnets to the rotor core while minimizing damage to the magnets.

[0005] In view of the above circumstances, one object of the present invention is to provide a rotating electric machine in which magnets can be reliably fixed to a rotor core while preventing damage to the magnets. [Means for solving the problem]

[0006] One aspect of the rotating electric machine of the present invention includes a rotor rotatable about a central axis and a stator positioned radially outward of the rotor. The rotor includes a rotor core formed by stacking multiple electromagnetic steel sheets in the axial direction and having multiple accommodating holes, and multiple magnets accommodated in the multiple accommodating holes. The rotor core includes a first recess recessed from a first core end face on one axial side to the other axial side, a first crimping portion provided on a bottom surface of the first recess, and a first protruding portion extending from an inner peripheral edge of the accommodating hole toward the magnet in a direction intersecting the axial direction and abutting against a side surface of the magnet. [Effects of the Invention]

[0007] According to one aspect of the present invention, there is provided a rotating electric machine in which the magnet can be securely fixed to the rotor core while preventing damage to the magnet. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a cross-sectional view of a rotating electrical machine according to an embodiment. [Figure 2] FIG. 2 is a cross-sectional view showing a part of the rotating electric machine according to the embodiment, taken along line II-II in FIG. [Figure 3] FIG. 3 is a view of a part of a rotor core of a rotor according to an embodiment, viewed from the axial direction. [Figure 4] FIG. 4 is a perspective view showing a part of a rotor core according to an embodiment of the present invention. [Figure 5] FIG. 5 is a perspective cross-sectional view of a rotor core according to one embodiment. [Figure 6] FIG. 6 is a cross-sectional view of a rotor core according to one embodiment. [Figure 7]FIG. 7 is a cross-sectional view showing a rotor core according to one embodiment in the middle of assembly. [Figure 8] FIG. 8 is a cross-sectional view of a rotor core according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, a rotating electric machine according to an embodiment of the present invention will be described with reference to the drawings. Note that the scope of the present invention is not limited to the following embodiments, and can be modified as desired within the scope of the technical concept of the present invention. In addition, in the following drawings, the scale and number of each structure may differ from the actual structure in order to make each configuration easier to understand.

[0010] The Z-axis direction shown in each figure as appropriate is the up-down direction, with the positive side being the "upper side" and the negative side being the "lower side." The central axis J shown in each figure as appropriate is a virtual line parallel to the Z-axis direction and extending in the up-down direction. In the following description, the axial direction of the central axis J, i.e., the direction parallel to the up-down direction, will be simply referred to as the "axial direction," the radial direction centered on the central axis J will be simply referred to as the "radial direction," and the circumferential direction centered on the central axis J will be simply referred to as the "circumferential direction." The arrow θ shown in each figure as appropriate indicates the circumferential direction. The arrow θ points clockwise around the central axis J when viewed from above. In the following description, the side of the circumferential direction toward which the arrow θ points relative to a certain object, i.e., the side proceeding clockwise when viewed from above, will be referred to as the "one circumferential side," and the side of the circumferential direction opposite to the side toward which the arrow θ points relative to a certain object, i.e., the side proceeding counterclockwise when viewed from above, will be referred to as the "other circumferential side."

[0011] Note that the terms "upper direction," "upper side," and "lower side" are simply names used to explain the relative positions of the various parts, and the actual relative positions may be other than those indicated by these names.

[0012] [Rotating Electric Machines] As shown in FIG. 1, the rotating electric machine 1 is an inner rotor type rotating electric machine. In this embodiment, the rotating electric machine 1 is a three-phase AC rotating electric machine. The rotating electric machine 1 is, for example, a three-phase motor that is driven by a three-phase AC power supply. The rotating electric machine 1 includes a housing 2, a rotor 10, a stator 60, a bearing holder 4, and bearings 5a and 5b.

[0013] The housing 2 accommodates the rotor 10, the stator 60, the bearing holder 4, and the bearings 5a and 5b inside. The bottom of the housing 2 holds the bearing 5b. The bearing holder 4 holds the bearing 5a. The bearings 5a and 5b are, for example, ball bearings.

[0014] The stator 60 is located radially outside the rotor 10. The stator 60 has a stator core 61, an insulator 64, and a plurality of coils 65. As shown in FIGS. 1 and 2 , the stator core 61 has a core back 62 and a plurality of teeth 63. The core back 62 is located radially outside the rotor core 20, which will be described later.

[0015] 2, the core back 62 has an annular shape that surrounds the rotor core 20. The core back 62 has an annular shape with the central axis J as its center, for example.

[0016] The teeth 63 extend radially inward from the core back 62. The teeth 63 are arranged side by side at intervals in the circumferential direction. For example, the teeth 63 are arranged at equal intervals around the circumference. For example, 48 teeth 63 are provided. That is, the number of slots 67 of the rotating electric machine 1 is 48, for example.

[0017] As shown in FIG. 1 , multiple coils 65 are attached to a stator core 61. The multiple coils 65 are attached to teeth 63, for example, via insulators 64. In this embodiment, the coils 65 are distributed wound. That is, each coil 65 is wound across multiple teeth 63. In this embodiment, the coils 65 are full-pitch wound. That is, the circumferential pitch between the slots of the stator 60 into which the coils 65 are inserted is equal to the circumferential pitch of the magnetic poles generated when three-phase AC power is supplied to the stator 60. The number of poles of the rotating electric machine 1 is, for example, 8. That is, the rotating electric machine 1 is, for example, an 8-pole, 48-slot rotating electric machine. As such, in the rotating electric machine 1 of this embodiment, when the number of poles is N, the number of slots is N×6.

[0018] The rotor 10 is rotatable about a central axis J. As shown in FIG. 2, the rotor 10 includes a shaft 11, a rotor core 20, and a plurality of magnets 40. The shaft 11 is cylindrical and extends axially about the central axis J. As shown in FIG. 1, the shaft 11 is supported by bearings 5a and 5b so as to be rotatable about the central axis J.

[0019] The rotor core 20 is made of a magnetic material and is fixed to the outer peripheral surface of the shaft 11. The rotor core 20 has a through hole 21 that passes through the rotor core 20 in the axial direction. As shown in FIG. 2, the through-hole 21 has a circular shape centered on the central axis J when viewed in the axial direction. The shaft 11 passes through the through hole 21. The shaft 11 is fixed in the through hole 21 by, for example, press fitting. The rotor core 20 is configured, for example, by stacking a plurality of electromagnetic steel plates 25 in the axial direction.

[0020] As shown in FIGS. 2 to 4, the rotor core 20 has a plurality of accommodating holes 30. The plurality of accommodating holes 30, for example, penetrate the rotor core 20 in the axial direction. A plurality of magnets 40 are accommodated inside the plurality of accommodating holes 30. The plurality of accommodating holes 30 include a pair of first accommodating holes 31a, 31b and a second accommodating hole 32.

[0021] The type of the multiple magnets 40 is not particularly limited. The magnets 40 may be, for example, neodymium magnets or ferrite magnets. The multiple magnets 40 include a pair of first magnets 41a, 41b and a second magnet 42. The pair of first magnets 41a, 41b and the second magnet 42 form poles.

[0022] In this embodiment, the pair of first accommodating holes 31a, 31b, the pair of first magnets 41a, 41b, the second accommodating holes 32, and the second magnets 42 are provided in plural numbers at intervals in the circumferential direction. For example, eight pairs of first accommodating holes 31a, 31b, the pair of first magnets 41a, 41b, the second accommodating holes 32, and the second magnets 42 are provided.

[0023] The rotor 10 has a plurality of magnetic pole portions 70, each including a pair of first accommodating holes 31a, 31b, a pair of first magnets 41a, 41b, a second accommodating hole 32, and a second magnet 42. As shown in FIG. 2, for example, eight magnetic pole portions 70 are provided. The magnetic pole portions 70 are arranged, for example, at equal intervals around the circumference in the circumferential direction. The magnetic pole portions 70 include a plurality of magnetic pole portions 70N having north poles on the outer peripheral surface of the rotor core 20 and a plurality of magnetic pole portions 70S having south poles on the outer peripheral surface of the rotor core 20. For example, four magnetic pole portions 70N and four magnetic pole portions 70S are provided. The four magnetic pole portions 70N and four magnetic pole portions 70S are arranged alternately in the circumferential direction. The configurations of the magnetic pole portions 70 are similar except that the magnetic poles on the outer peripheral surface of the rotor core 20 are different and the circumferential positions are different.

[0024] As shown in FIGS. 3 and 4 , in the magnetic pole portion 70, the pair of first accommodating holes 31a, 31b are spaced apart from each other in the circumferential direction. The first accommodating hole 31a is located, for example, on one circumferential side (+θ side) of the first accommodating hole 31b. The first accommodating holes 31a, 31b extend, for example, in a substantially linear manner obliquely relative to the radial direction when viewed in the axial direction. The pair of first accommodating holes 31a, 31b extend in directions that separate them from each other in the circumferential direction as they move from the radially inner side to the radially outer side when viewed in the axial direction. In other words, the circumferential distance between the first accommodating hole 31a and the first accommodating hole 31b increases as they move from the radially inner side to the radially outer side. The first accommodating hole 31a is located, for example, on one circumferential side as they move from the radially inner side to the radially outer side. The first accommodating hole 31b is located, for example, on the other circumferential side (−θ side) as they move from the radially inner side to the radially outer side. The radially outer ends of the first accommodating holes 31a and 31b are located at the radially outer peripheral edge of the rotor core 20.

[0025] For example, when viewed in the axial direction, the first accommodating holes 31a and 31b are arranged on either side of the magnetic pole center line IL1 shown in FIG. 3, which constitutes the d-axis. The magnetic pole center line IL1 is an imaginary line that passes through the circumferential center of the magnetic pole portion 70 and the central axis J and extends in the radial direction. For example, when viewed in the axial direction, the first accommodating holes 31a and 31b are arranged line-symmetrically with respect to the magnetic pole center line IL1. Hereinafter, a description of the first accommodating hole 31b, which has the same configuration as the first accommodating hole 31a except for being line-symmetric with respect to the magnetic pole center line IL1, may be omitted.

[0026] The first accommodating hole 31a has a first linear portion 31c, an inner end portion 31d, and an outer end portion 31e. The first linear portion 31c extends linearly in the extension direction of the first accommodating hole 31a when viewed in the axial direction. The first linear portion 31c has, for example, a rectangular shape when viewed in the axial direction. The inner end portion 31d is connected to the radially inner end portion of the first linear portion 31c. The inner end portion 31d is the radially inner end portion of the first accommodating hole 31a. The outer end portion 31e is connected to the radially outer end portion of the first linear portion 31c. The outer end portion 31e is the radially outer end portion of the first accommodating hole 31a. The outer end portion 31e extends radially outward from the radially outer end portion of the first linear portion 31c along the magnetic pole center line IL1. The first receiving hole 31b has a first linear portion 31f, an inner end portion 31g, and an outer end portion 31h.

[0027] The second accommodating hole 32 is located circumferentially between the radially outer ends of the pair of first accommodating holes 31a, 31b. That is, in this embodiment, the second accommodating hole 32 is located circumferentially between the outer end 31e and the outer end 31h. The second accommodating hole 32 extends in a substantially linear manner in a direction perpendicular to the radial direction when viewed in the axial direction, for example. The second accommodating hole 32 extends in a direction perpendicular to the magnetic pole center line IL1 when viewed in the axial direction, for example. The pair of first accommodating holes 31a, 31b and the second accommodating hole 32 are arranged along a V shape when viewed in the axial direction, for example.

[0028] In this specification, "an object extending in a direction perpendicular to a certain direction" includes not only the case where an object extends in a direction strictly perpendicular to a certain direction, but also the case where an object extends in a direction approximately perpendicular to a certain direction. "A direction approximately perpendicular to a certain direction" includes a direction tilted within a range of several degrees [°] from the direction strictly perpendicular to a certain direction due to, for example, manufacturing tolerances.

[0029] When viewed in the axial direction, the magnetic pole center line IL1, for example, passes through the circumferential center of the second accommodating hole 32. In other words, the circumferential position of the circumferential center of the second accommodating hole 32 coincides with the circumferential position of the circumferential center of the magnetic pole portion 70, for example. The shape of the second accommodating hole 32 when viewed in the axial direction is, for example, a shape that is line-symmetrical with respect to the magnetic pole center line IL1. The second accommodating hole 32 is located on the radially outer peripheral edge of the rotor core 20.

[0030] The second accommodating hole 32 has a second linear portion 32a, one end portion 32b, and the other end portion 32c. The second linear portion 32a extends linearly in the extension direction of the second accommodating hole 32 when viewed in the axial direction. The second linear portion 32a has, for example, a rectangular shape when viewed in the axial direction. The one end portion 32b is connected to an end portion on one circumferential side (+θ side) of the second linear portion 32a. The one end portion 32b is an end portion on one circumferential side of the second accommodating hole 32. The one end portion 32b is disposed on the other circumferential side (-θ side) of the outer end portion 31e of the first accommodating hole 31a with a gap therebetween. The other end portion 32c is connected to an end portion on the other circumferential side (-θ side) of the second linear portion 32a. The other end portion 32c is an end portion on the other circumferential side of the second accommodating hole 32. The other end 32c is disposed on one circumferential side of the outer end 31h of the first receiving hole 31b with a gap therebetween.

[0031] The pair of first magnets 41a, 41b are housed inside the pair of first housing holes 31a, 31b, respectively. The first magnet 41a is housed inside the first housing hole 31a. The first magnet 41b is housed inside the first housing hole 31b. The pair of first magnets 41a, 41b are, for example, rectangular when viewed in the axial direction. The pair of first magnets 41a, 41b have the same length in the extension direction. The pair of first magnets 41a, 41b have the same length in the direction perpendicular to the extension direction.

[0032] The first magnets 41a, 41b are, for example, rectangular parallelepiped-shaped. As shown in Fig. 5, the axial length of the first magnets 41a, 41b is, for example, slightly shorter than the overall axial length of the first accommodating holes 31a, 31b. As shown in Figs. 3 and 4, the pair of first magnets 41a, 41b are arranged with a gap between them in the circumferential direction. The first magnet 41a is, for example, located on one circumferential side (+θ side) of the first magnet 41b.

[0033] The first magnet 41a extends along the first accommodating hole 31a when viewed in the axial direction. The first magnet 41b extends along the first accommodating hole 31b when viewed in the axial direction. For example, the first magnets 41a, 41b extend in a substantially linear manner in a direction oblique to the radial direction when viewed in the axial direction. The pair of first magnets 41a, 41b extend in directions that separate them circumferentially from each other as they move from the radially inner side to the radially outer side when viewed in the axial direction. In other words, the circumferential distance between the first magnet 41a and the first magnet 41b increases as they move from the radially inner side to the radially outer side.

[0034] For example, the first magnet 41a is positioned on one circumferential side (+θ side) as one moves from the radially inner side to the radially outer side. The first magnet 41b is positioned on the other circumferential side (-θ side) as one moves from the radially inner side to the radially outer side. The first magnet 41a and the first magnet 41b are arranged, for example, on either side of the magnetic pole center line IL1 when viewed in the axial direction. The first magnet 41a and the first magnet 41b are arranged, for example, line-symmetrically with respect to the magnetic pole center line IL1 when viewed in the axial direction. Below, a description of the first magnet 41b, which has the same configuration as the first magnet 41a except for being line-symmetric with respect to the magnetic pole center line IL1, may be omitted.

[0035] The first magnet 41a is inserted into the first accommodating hole 31a. More specifically, the first magnet 41a is inserted into the first straight portion 31c. When viewed in the axial direction, the length of the first magnet 41a in the direction in which the first straight portion 31c extends is the same as, for example, the length of the first straight portion 31c.

[0036] When viewed in the axial direction, both ends of the first magnet 41a in its extension direction are spaced apart from both ends of the first accommodating hole 31a in its extension direction. When viewed in the axial direction, an inner end 31d and an outer end 31e are adjacently disposed on both sides of the first magnet 41a in its extension direction. In this embodiment, the inner end 31d constitutes the first flux barrier portion 51a. The outer end 31e constitutes the first flux barrier portion 51b. That is, when viewed in the axial direction, the rotor core 20 has a pair of first flux barrier portions 51a, 51b disposed on either side of the first magnet 41a in its extension direction. When viewed in the axial direction, the rotor core 20 has a pair of first flux barrier portions 51c, 51d disposed on either side of the first magnet 41b in its extension direction.

[0037] The first flux barrier portion 51b located on the radially outer side extends radially outward from the radial end of the first magnet 41a in parallel to the magnetic pole center line IL1. The first flux barrier portion 51d located on the radially outer side extends radially outward from the radial end of the first magnet 41b in parallel to the magnetic pole center line IL1.

[0038] As described above, the rotor core 20 has a pair of first flux barrier portions 51a, 51b, 51c, and 51d arranged on either side of each of the first magnets 41a and 41b in the direction in which the first magnets 41a and 41b extend, as viewed in the axial direction. The first flux barrier portions 51a, 51b, 51c, and 51d, as well as the second flux barrier portions 52a and 52b described below, are portions that can suppress the flow of magnetic flux. In other words, magnetic flux does not easily pass through each flux barrier portion. Each flux barrier portion is not particularly limited as long as it can suppress the flow of magnetic flux, and may include a gap portion or a non-magnetic portion such as a resin portion.

[0039] The second magnet 42 is accommodated inside the second accommodating hole 32. The second magnet 42 is disposed radially outward of the radially inner ends of the pair of first magnets 41a, 41b, at a circumferential position between the pair of first magnets 41a, 41b. The second magnet 42 extends along the second accommodating hole 32 when viewed in the axial direction. The second magnet 42 extends in a direction perpendicular to the radial direction when viewed in the axial direction. The pair of first magnets 41a, 41b and the second magnet 42 are arranged, for example, along a V shape when viewed in the axial direction.

[0040] In this specification, "the second magnet is positioned at a circumferential position between a pair of first magnets" means that the circumferential position of the second magnet is included in the circumferential position between the pair of first magnets, and the radial position of the second magnet relative to the first magnets is not particularly limited.

[0041] The shape of the second magnet 42 as viewed in the axial direction is, for example, symmetrical with respect to the magnetic pole center line IL1. The second magnet 42 is, for example, rectangular as viewed in the axial direction. As viewed in the axial direction, the radial length of the second magnet 42 is shorter than the length of the first magnets 41a, 41b in a direction perpendicular to the extension direction of the first magnets 41a, 41b. By making the radial length of the second magnet 42 shorter than the length of the first magnets 41a, 41b in a direction perpendicular to the extension direction of the first magnets 41a, 41b, and thereby making the second magnet 42 thinner, the weight of the second magnet 42 can be made smaller than the weight of each of the first magnets 41a, 41b. By reducing the weight of the second magnet 42, the centrifugal force of the second magnet 42 during rotation of the rotor 10 can be reduced. Therefore, the load on the rotor core 20 can be reduced.

[0042] By making the second magnet 42 thinner, the second magnet 42 can be arranged radially outside the rotor core 20. By arranging the second magnet 42 radially outside the rotor core 20, it is possible to increase the output of the rotating electric machine 1. Because the magnetization of the second magnet 42 is strengthened by the first magnets 41a and 41b, it is possible to increase the strength of the rotor core 20 and increase the output of the rotating electric machine 1 without compromising the demagnetization resistance. Furthermore, high demagnetization resistance can be obtained with a small amount of magnet.

[0043] The second magnet 42 has, for example, a rectangular parallelepiped shape. This can increase the output of the rotating electric machine 1. The axial length of the second magnet 42 is, for example, slightly shorter than the overall axial length of the second accommodating hole 32. As shown in FIGS. 3 and 4, the radially inner portion of the second magnet 42 is, for example, located circumferentially between the radially outer ends of the pair of first magnets 41a, 41b. The radially outer portion of the second magnet 42 is, for example, located radially outward of the pair of first magnets 41a, 41b.

[0044] The second magnet 42 is inserted into the second accommodating hole 32. More specifically, the second magnet 42 is inserted into the second straight portion 32a. When viewed in the axial direction, the length of the second magnet 42 in the direction in which the second straight portion 32a extends is the same as, for example, the length of the second straight portion 32a.

[0045] When viewed in the axial direction, both end portions of the second magnet 42 in the extension direction are disposed apart from both end portions of the second accommodating hole 32 in the extension direction. When viewed in the axial direction, one end portion 32b and the other end portion 32c are disposed adjacent to each other on both sides of the second magnet 42 in the extension direction of the second magnet 42. Here, in this embodiment, the one end portion 32b constitutes the second flux barrier portion 52a. The other end portion 32c constitutes the second flux barrier portion 52b. In other words, when viewed in the axial direction, the rotor core 20 has a pair of second flux barrier portions 52a, 52b disposed on either side of the second magnet 42 in the extension direction of the second magnet 42.

[0046] The second flux barrier portions 52a, 52b each have an arc shape that extends radially inward as it extends from the circumferential end of the second magnet 42 away from the second magnet 42 in the circumferential direction. If the second flux barrier portions 52a, 52b extend radially outward, the distance between the second flux barrier portions 52a, 52b and the outer peripheral surface of the rotor core 20 becomes shorter, and the load on the rotor core 20 may increase due to centrifugal force during rotation. By having the second flux barrier portions 52a, 52b extend radially inward, the load on the rotor core 20 can be reduced. By making the second flux barrier portions 52a, 52b arc-shaped, stress concentration at the intersections between the circumferentially extending portions and the radially extending portions can be alleviated, further reducing the load on the rotor core 20.

[0047] The pair of second flux barrier portions 52a, 52b and the second magnet 42 are positioned circumferentially between the first flux barrier portion 51b, which is located radially outward of the pair of first flux barrier portions 51a, 51b that sandwich the first magnet 41a, and the first flux barrier portion 51d, which is located radially outward of the pair of first flux barrier portions 51c, 51d that sandwich the first magnet 41b.

[0048] The magnetic poles of the first magnet 41a are arranged along a direction perpendicular to the extension direction of the first magnet 41a when viewed in the axial direction. The magnetic poles of the first magnet 41b are arranged along a direction perpendicular to the extension direction of the first magnet 41b when viewed in the axial direction. The magnetic poles of the second magnet 42 are arranged along the radial direction.

[0049] The magnetic poles of the first magnet 41a located on the radially outer side, the magnetic poles of the first magnet 41b located on the radially outer side, and the magnetic poles of the second magnet 42 located on the radially outer side are all the same. The magnetic poles of the first magnet 41a located on the radially inner side, the magnetic poles of the first magnet 41b located on the radially inner side, and the magnetic poles of the second magnet 42 located on the radially inner side are all the same.

[0050] 3, in the magnetic pole portion 70N, the magnetic pole of the first magnet 41a located on the radially outer side, the magnetic pole of the first magnet 41b located on the radially outer side, and the magnetic pole of the second magnet 42 located on the radially outer side are, for example, north poles. In the magnetic pole portion 70N, the magnetic pole of the first magnet 41a located on the radially inner side, the magnetic pole of the first magnet 41b located on the radially inner side, and the magnetic pole of the second magnet 42 located on the radially inner side are, for example, south poles.

[0051] Although not shown in the drawings, in the magnetic pole portion 70S, the magnetic poles of the magnets 40 are arranged inverted relative to the magnetic pole portion 70N. That is, in the magnetic pole portion 70S, the magnetic pole located on the radially outer side of the magnetic poles of the first magnet 41a, the magnetic pole located on the radially outer side of the magnetic poles of the first magnet 41b, and the magnetic pole located on the radially outer side of the magnetic poles of the second magnet 42 are, for example, S poles. In the magnetic pole portion 70S, the magnetic pole located on the radially inner side of the magnetic poles of the first magnet 41a, the magnetic pole located on the radially inner side of the magnetic poles of the first magnet 41b, and the magnetic pole located on the radially inner side of the magnetic poles of the second magnet 42 are, for example, N poles.

[0052] As shown in FIG. 6, the rotor core 20 has a first recess 80, a first crimping portion 82, and a first protruding portion 84.

[0053] As shown in FIGS. 3 and 4 , the first recesses 80 are provided corresponding to the respective accommodating holes 30 (first accommodating holes 31a, 31b, second accommodating holes 32). In this embodiment, the first recesses 80 are provided adjacent to and radially inward of the respective accommodating holes 30 (first accommodating holes 31a, 31b, second accommodating holes 32). The first recesses 80a provided corresponding to the first accommodating hole 31a are provided radially inward with respect to the first linear portion 31c of the first accommodating hole 31a and spaced apart in the direction in which the first linear portion 31c extends, for example, two first recesses 80a. The first recesses 80b provided corresponding to the first accommodating hole 31b are provided radially inward with respect to the first linear portion 31f of the first accommodating hole 31b and spaced apart in the direction in which the first linear portion 31f extends, for example, two first recesses 80b. The first recesses 80c provided adjacent to the second accommodating hole 32 are provided radially inward of the second straight portion 32a of the second accommodating hole 32, with, for example, two recesses provided at intervals in the direction in which the second straight portion 32a extends.

[0054] As shown in FIG. 6 , each first recess 80 is recessed from the first core end face 20a on one axial side of the rotor core 20 toward the other axial side. The multiple electromagnetic steel sheets 25 include one or more first electromagnetic steel sheets 25P located on one axial side and second electromagnetic steel sheets 25Q located on the other axial side of the first electromagnetic steel sheets 25P. Each first recess 80 is formed by a notch 81 provided in one or more first electromagnetic steel sheets 25P located on one axial side. In this embodiment, each first recess 80 is formed by a notch 81 provided in, for example, two first electromagnetic steel sheets 25P located on the most axial side. The notch 81 is provided to communicate with the accommodation hole 30. In this embodiment, the notch 81 is provided, for example, in a U-shape when viewed in the axial direction.

[0055] The bottom surface 81d of the first recess 80 is exposed inside the first recess 80 and is formed by a second electromagnetic steel sheet 25Q arranged on the other axial side of the first electromagnetic steel sheet 25P. The bottom surface 81d of the first recess 80 is arranged at the same axial position as the magnet end face 40f on one axial side of the magnet 40, or on the other axial side of the magnet end face 40f. In this embodiment, the bottom surface 81d of the first recess 80 is arranged on the other axial side of the magnet end face 40f. The magnet end face 40f is arranged on the other axial side of the first core end face 20a. In other words, the magnet end face 40f is arranged at a position recessed toward the other axial side of the first core end face 20a. The magnet end face 40g on the other axial side of the magnet 40 is arranged at approximately the same axial position as the second core end face 20b on the other axial side of the rotor core 20. This is achieved by, as shown in Figure 7, when assembling the rotor core 20, butting the second core end face 20b of the rotor core 20 against the assembly work surface F, and inserting the magnets 40 into each accommodating hole 30 until the magnet end face 40g on the other axial side butts against the second core end face 20b.

[0056] As shown in Fig. 6, the first crimping portion 82 is provided on the bottom surface 81d of the first recess 80. As shown in Fig. 7, the first crimping portion 82 is provided by crimping the second electromagnetic steel sheet 25Q exposed inside the first recess 80 with a tool T such as a punch. As shown in Fig. 6, the first crimping portion 82 is a depression provided by crimping the second electromagnetic steel sheet 25Q with the tool T.

[0057] The first protrusions 84 are formed by crimping the second electromagnetic steel sheet 25Q with a tool T inside the first recess 80, so that the second electromagnetic steel sheet 25Q protrudes toward the magnet 40 in a direction intersecting the axial direction of the inner peripheral edge of the accommodating hole 30. The first protrusions 84 abut against the side surfaces 40s of the magnet 40. When the first protrusions 84 abut against the side surfaces 40s of the magnet 40, the side surfaces 40t of the magnet 40 facing radially outward are pressed against the inner peripheral surfaces of the accommodating holes 30.

[0058] As shown in Figure 6, each magnet 40 (first magnets 41a, 41b, second magnet 42) is fixed to the rotor core 20 by the first protrusion 84 abutting against the side surface 40s facing radially inward of the magnet 40 and the side surface 40t facing radially outward abutting against the inner surface of the accommodating hole 30 (first accommodating hole 31a, 31b, second accommodating hole 32).

[0059] According to the above configuration, the first crimping portion 82 is provided on the bottom surface 81d of the first recess 80 recessed from the first core end face 20a of the rotor core 20 to the other axial side, and the first protrusion 84 abuts against the side surface 40s of the magnet 40. This ensures that the magnet 40 is securely fixed to the rotor core 20. Furthermore, because the first protrusion 84 abuts against the side surface 40s of the magnet 40, damage to the magnet 40 is reduced. Therefore, the magnet 40 can be securely fixed to the rotor core 20 while reducing damage to the magnet 40.

[0060] According to the above configuration, the bottom surface 81d of the first recess 80 is positioned at the same axial position as the magnet end surface 40f on one side of the magnet 40, or on the other axial side, so that the first protrusion 84 reliably abuts against the side surface 40s of the magnet 40.

[0061] According to the above configuration, by providing notch 81 in first electromagnetic steel sheet 25P, first recess 80 can be easily provided. Furthermore, because bottom surface 81d of first recess 80 is formed by second electromagnetic steel sheet 25Q, first protrusion 84 can be provided by making second electromagnetic steel sheet 25Q protrude toward magnet 40 in a direction intersecting the axial direction.

[0062] According to the above configuration, even if the magnet end face 40f does not protrude to one side in the axial direction from the first core end face 20a but is located to the other side in the axial direction from the first core end face 20a, the magnet 40 can be securely fixed to the rotor core 20 by abutting the first protruding portion 84 against the side surface 40s of the magnet 40.

[0063] According to the above configuration, by arranging the first protrusion 84 radially inward relative to the magnet 40, the magnet 40 can be arranged radially outward of the rotor core 20. This allows the rotating electric machine 1 to have a higher output.

[0064] According to the above configuration, the notch 81 communicates with the accommodation hole 30, so that the notch 81 and the accommodation hole 30 can be easily formed as a single opening in the laminated steel plate.

[0065] While the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to these examples. The shapes and combinations of the components shown in the above examples are merely examples, and various modifications can be made based on design requirements, etc., without departing from the spirit of the present invention. For example, as shown in Figure 8, the rotor core may have a second crimping portion 92 formed on the second core end face 20b on the other side in the axial direction, and a second protruding portion 94 that protrudes toward the magnet 40 in a direction intersecting the inner peripheral edge of the accommodating hole 30 with the axial direction and abuts against the side surface 40s of the magnet 40.

[0066] According to the above configuration, in addition to the first protrusion 84, by providing a second crimping portion 92 and a second protrusion 94 on the second core end face 20b side on the other axial side of the rotor core 20, it is possible to firmly fix the magnet 40 on one axial side and the other axial side.

[0067] In the above embodiment, two first recesses 80 are provided for each accommodating hole 30, but the number is not limited thereto. One first recess 80 may be provided for each accommodating hole 30, or three or more first recesses 80 may be provided for each accommodating hole 30. Furthermore, although the first recesses 80 are provided radially inward relative to each accommodating hole 30, this is not limitative. The first recesses 80 may be provided radially outward relative to each accommodating hole 30, or may be provided on both the radially inner and radially outer sides of each accommodating hole 30.

[0068] Furthermore, the first recess 80 is formed by a notch 81 provided in the first electromagnetic steel sheet 25P so as to face the accommodating hole 30, but is not limited to this. The first recess 80 may also be formed by a hole provided at a position separated from the accommodating hole 30.

[0069] The rotating electric machine to which the present invention is applied is not limited to a motor, but may also be a generator. In this case, the rotating electric machine may be a three-phase AC generator. The application of the rotating electric machine is not particularly limited. The rotating electric machine may be mounted, for example, on a vehicle or on equipment other than a vehicle. The number of poles and the number of slots of the rotating electric machine are not particularly limited. The coils in the rotating electric machine may be configured in any winding method. The configurations described above in this specification can be combined as appropriate within a range that is not mutually contradictory. [Explanation of symbols]

[0070] REFERENCE SIGNS LIST 1... rotating electric machine, 10... rotor, 20... rotor core, 20a... first core end face, 20b... second core end face, 25... electromagnetic steel sheet, 25P... first electromagnetic steel sheet, 25Q... second electromagnetic steel sheet, 30... accommodation hole, 40... magnet, 40f... magnet end face, 40s... side face, 40t... side face, 60... stator, 80, 80a, 80b, 80c... first recess, 81d... bottom face, 81... notch, 82... first crimping portion, 84... first protruding portion, 92... second crimping portion, 94... second protruding portion, J... central axis

Claims

1. a rotor rotatable about a central axis; a stator positioned radially outward of the rotor, The rotor is a rotor core formed by laminating a plurality of electromagnetic steel plates in the axial direction and having a plurality of accommodating holes; a plurality of magnets respectively housed inside the plurality of housing holes; The rotor core is a first recess recessed from a first core end face on one side in the axial direction to the other side in the axial direction; a first crimping portion provided on a bottom surface of the first recess; a first protrusion that protrudes toward the magnet in a direction intersecting the axial direction of an inner peripheral edge of the accommodating hole and abuts against a side surface of the magnet in a state where an axial end face of the magnet is open, a magnet end face on one side in the axial direction of the magnet is positioned on the other side in the axial direction than the first core end face;

2. A rotor rotatable around a central axis; a stator positioned radially outward of the rotor, The rotor is a rotor core formed by laminating a plurality of electromagnetic steel plates in the axial direction and having a plurality of accommodating holes; a plurality of magnets respectively housed inside the plurality of housing holes; The rotor core is a first recess recessed from a first core end face on one side in the axial direction to the other side in the axial direction; a first crimping portion provided on a bottom surface of the first recess; a first protrusion that protrudes toward the magnet in a direction intersecting the axial direction of an inner peripheral edge of the accommodating hole and abuts against a side surface of the magnet in a state where an axial end face of the magnet is open, The first recess is a notch that communicates with the accommodation hole.

3. 3. The rotating electric machine according to claim 1, wherein a bottom surface of the first recess is positioned at the same axial position as a magnet end face on one side of the magnet in the axial direction, or on the other side of the magnet end face in the axial direction.

4. the plurality of electromagnetic steel sheets include one or more first electromagnetic steel sheets located on one side in the axial direction, and a second electromagnetic steel sheet located on the other side in the axial direction relative to the first electromagnetic steel sheet, the first recess is a hole or a notch provided in the first electromagnetic steel plate, the bottom surface of the first recess is exposed to the inside of the first recess and is made of the second electromagnetic steel sheet; The rotating electric machine according to any one of claims 1 to 3.

5. The first protrusion is disposed on the inner side of the magnet in a radial direction intersecting the axial direction. The rotating electric machine according to any one of claims 1 to 4.

6. The rotor core is a second crimping portion provided on the second core end surface on the other side in the axial direction; A rotating electric machine as described in any one of claims 1 to 5, wherein the inner peripheral edge of the accommodating hole has a second protrusion that protrudes toward the magnet in a direction intersecting the axial direction and abuts against a side surface of the magnet.

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