Rotor for rotating electric machines

Abstract

In a rotor for a rotating electric machine having a skew structure, the short-circuit magnetic flux is reduced without increasing the axial size of the entire rotor core. [Solution] A rotor for a rotating electric machine having a skew structure is disclosed, comprising a rotor core including a first core and a second core stacked in the axial direction, a first magnet in a first magnet hole of the first core, a second magnet in a second magnet hole of the second core, and a non-magnetic member formed of a non-magnetic material and placed in at least one of the magnet holes of the first magnet hole and the second magnet hole, wherein the first core and the second core are in contact in the axial direction while being offset from each other by a skew angle in the circumferential direction, with the first magnet hole and the second magnet hole partially overlapping when viewed in the axial direction, and the non-magnetic member is positioned between the first magnet and the second magnet in the axial direction.

Description

Technical Field

[0001] The present disclosure relates to a rotor for a rotating electric machine.

Background Art

[0002] In a rotor for a rotating electric machine having a skew structure, a technique is known in which a non-magnetic core spacer is sandwiched between core blocks to seal the excess of the magnet fixing adhesive so that it does not protrude outside the rotor core, and the positioning of the skew of the magnet is realized by the non-magnetic core spacer.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in a rotor for a rotating electric machine having a skew structure, the magnets embedded in the rotor are displaced in the circumferential direction, so a magnetic flux short circuit occurs between the magnetic poles of the magnets whose magnetic pole positions are displaced. When a short-circuited magnetic flux occurs, the magnetic flux contributing to the generation of torque decreases, and although the torque ripple is reduced, the driving torque itself becomes small.

[0005] In this regard, in the conventional technology as described above, although the short-circuited magnetic flux can be reduced by providing a non-magnetic core spacer, there is a problem that the axial size of the entire rotor core increases by the axial thickness of the non-magnetic core spacer.

[0006] Therefore, on one side, an object of the present disclosure is to reduce the short-circuited magnetic flux in a rotor for a rotating electric machine having a skew structure without increasing the axial size of the entire rotor core.

Means for Solving the Problems

[0007] In one aspect, a rotor for a rotating electric machine having a skew structure. A rotor core including a first core and a second core stacked in the axial direction, A first magnet is placed in the first magnet hole of the first core, A second magnet is placed in the second magnet hole of the second core, Formed from a non-magnetic material, the magnet hole comprises a non-magnetic member in at least one of the first magnet hole and the second magnet hole, The first core and the second core are in contact in the axial direction while being offset from each other by a skew angle, such that the first magnet hole and the second magnet hole partially overlap when viewed in the axial direction. The non-magnetic member is provided in a rotor for a rotating electric machine, which is positioned axially between the first magnet and the second magnet. [Effects of the Invention]

[0008] In one aspect, according to this disclosure, in a rotor for a rotating electric machine having a skew structure, it is possible to reduce the short-circuit flux without increasing the axial size of the entire rotor core. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic cross-sectional view showing the cross-sectional structure of a rotating electric machine according to one embodiment. [Figure 2] This is a cross-sectional view of a rotating electric machine (a cross-sectional view taken from a plane perpendicular to the axial direction). [Figure 3] This is an explanatory diagram of the skew structure, showing the relationship between the misalignments between multiple core blocks. [Figure 4] This is an explanatory diagram of a two-tiered V-shaped skew structure. [Figure 5] This is a cross-sectional view passing through the permanent magnet of the first core. [Figure 6] This is a cross-sectional view passing through the permanent magnet of the second core. [Figure 7] This is a cross-sectional view passing through the permanent magnet of the third core. [Figure 8]It is a schematic cross-sectional view showing an example of a magnet cap structure, and is a cross-sectional view of a first core and a second core by a plane along line V-V in FIG. 5. [Figure 9] It is a cross-sectional view along line A-A in FIG. 8. [Figure 10] It is an explanatory view of an example of the concavo-convex shape for fitting of the magnet cap. [Figure 11] It is an explanatory view of another example of the concavo-convex shape for fitting of the magnet cap.

Mode for Carrying Out the Invention

[0010] Hereinafter, each embodiment will be described in detail with reference to the accompanying drawings. Note that the dimensional ratios in the drawings are merely examples and are not limited thereto, and the shapes etc. in the drawings may be exaggerated partially for convenience of explanation. Also, in the drawings, for ease of viewing, only some of the parts having the same attribute existing in plural may be provided with reference signs.

[0011] FIG. 1 is a cross-sectional view schematically showing the cross-sectional structure of a rotating electrical machine 10 according to an embodiment. FIG. 2 is a cross-sectional view of the rotating electrical machine 10 (a cross-sectional view by a plane perpendicular to the axial direction).

[0012] In FIG. 1, the axis X of the rotating electrical machine 10 is shown. In the following description, the axial direction refers to the direction in which the axis X, which is the rotation axis (rotation center) of the rotating electrical machine 10, extends, and the radial direction refers to the radial direction centered on the axis X. Therefore, the outer side in the radial direction refers to the side away from the axis X, and the inner side in the radial direction refers to the side toward the axis X. Also, the circumferential direction corresponds to the rotation direction around the axis X.

[0013] The rotating electrical machine 10 may be, for example, a motor for vehicle drive used in a hybrid vehicle or an electric vehicle. However, the rotating electrical machine 10 may be used for any other arbitrary application.

[0014] The rotating electrical machine 10 is, for example, an inner rotor type, and the stator 200 is provided so as to surround the outside in the radial direction of the rotor 100. The stator 200 is fixed to the motor housing 11. The stator 200 includes, for example, a stator core 220 made of a laminated steel sheet of an annular magnetic material, and a plurality of slots 222 around which coils 240 are wound are formed on the inner side in the radial direction of the stator core 220.

[0015] The rotor 100 is disposed on the inner side in the radial direction of the stator 200.

[0016] The rotor 100 includes a rotor core 120, a shaft 110, end plates 35A and 35B, and permanent magnets 160. Note that the end plates 35A and 35B may be omitted.

[0017] The rotor core 120 is fixed to the surface on the outer side in the radial direction of the shaft 110 and rotates integrally with the shaft 110. The rotor core 120 has a shaft hole 320 (see FIG. 2), and the shaft 110 is fitted into the shaft hole 320. The rotor core 120 is coupled in a manner having a radial interference fit with respect to the shaft 110. That is, the rotor core 120 and the shaft 110 are coupled to each other by fixing with an interference fit. For example, the rotor core 120 and the shaft 110 may be coupled in a manner having a radial interference fit by shrink fitting, press fitting, hydroforming, or the like. However, the coupling force between the rotor core 120 and the shaft 110 may include an axial force by a nut or the like in addition to the radial interference fit.

[0018] The shaft 110 is rotatably supported by the motor housing 11 via bearings 14a and 14b. Note that the shaft 110 defines the axis X of the rotating electrical machine 10.

[0019] The rotor core 120 is formed of, for example, a laminated steel sheet of an annular magnetic material. Permanent magnets 160 (see FIG. 5 etc.) are disposed inside the rotor core 120. Note that in a modified example, the rotor core 120 may be formed of a compacted body in which magnetic powder is compressed and solidified.

[0020] The rotor core 120 has an annular shape. In modified examples, the annular shape of the rotor core 120 does not need to be a perfect circle; for example, it may be a circular shape with a notch in part, or it may be an elliptical shape that is close to a circle.

[0021] As shown in Figure 2, the rotor core 120 has a rotationally symmetrical configuration with respect to the axis X when viewed in the axial direction. In the example shown in Figure 2, the rotor core 120 is configured such that each set of permanent magnets 160 overlaps each time it rotates 45 degrees around the axis X.

[0022] The multiple permanent magnets 160 are in the form of sintered magnets and may be formed from neodymium or the like. However, in a modified example, magnets formed from bonded magnet material may be used instead of the permanent magnets 160. In this embodiment, the permanent magnets 160 are magnetized such that the surface with the largest area among the rectangular parallelepipeds becomes the magnetic pole (N pole, S pole). Hereinafter, the surface of the permanent magnet 160 that has a magnetic pole will be referred to as the magnetic pole surface.

[0023] In this embodiment, as an example, as shown in Figure 2, the multiple permanent magnets 160 are arranged in a manner that is rotationally symmetrical with respect to each magnetic pole when viewed in the axial direction. The multiple permanent magnets 160 are arranged in a manner that alternates between south poles and north poles in the circumferential direction. In this embodiment, there are eight magnetic poles, but the number of magnetic poles is arbitrary. In this embodiment, the multiple permanent magnets 160 are linear and identical in shape when viewed in the axial direction, but they may be different in shape. Also, some or all of the multiple permanent magnets 160 may be arc-shaped when viewed in the axial direction.

[0024] Although Figure 1 shows a rotating electric machine 10 having a specific structure, the structure of the rotating electric machine 10 is not limited to this specific structure. For example, in Figure 1, the shaft 110 is hollow, but it may be solid.

[0025] In this embodiment, the rotor 100 has a skew structure. Specifically, the rotor core 120 of the rotor 100 is formed by stacking a plurality of core blocks in the axial direction, with each block offset from the others by a skew angle in the circumferential direction.

[0026] Figure 3 is an explanatory diagram of a skew structure, showing the relationship between the misalignments of multiple core blocks. In Figure 3, the relationship between the misalignments of eight core blocks is shown, with a dotted line L2 representing the angle (0 degrees) at the initial position (reference position). Then, dotted lines L3 and L1 are shown, representing the angular position shifted in the positive direction relative to the initial position and the angular position shifted in the negative direction relative to the initial position, respectively. In Figure 3, dotted lines L1 to L3 show the amount of circumferential misalignment (skew angle) between the multiple core blocks. The example shown in Figure 3 is a so-called three-tiered V-shaped skew structure, with the first core 140, second core 145, second core 145, third core 150, third core 150, second core 145, second core 145, and first core 140, in that order from top to bottom. The second core 145 is not displaced from its initial position, the first core 140 is displaced in the negative direction from its initial position, and the third core 150 is displaced in the positive direction from its initial position. In the modified example, the skew structure may be of other forms, and the number of stages is arbitrary. For example, as shown in Figure 4, it may be a two-stage V-shaped skew structure, i.e., a structure consisting of a first core 140A, a second core 145A, a second core 145A, and a first core 140A.

[0027] Figure 5 is a cross-sectional view of the first core 140 through the permanent magnet 160, Figure 6 is a cross-sectional view of the second core 145 through the permanent magnet 160, and Figure 7 is a cross-sectional view of the third core 150 through the permanent magnet 160. Figures 5 to 7 are cross-sectional views taken with a plane perpendicular to the axis X.

[0028] The configurations of the first core 140, the second core 145, and the third core 150 are rotationally symmetric, with a skew angle between them.

[0029] In this embodiment, as described above, the rotor 100 has 8 poles, and each permanent magnet 160 is placed in the magnet holes 122, 124, and 126 of the first core 140, second core 145, and third core 150, respectively.

[0030] As shown in Figures 5 to 7, a flux barrier 132 is formed continuously from the longitudinal end of the magnet hole 122 of the rotor core 120. Similarly, flux barriers 134 and 136 are formed continuously from the longitudinal ends of the magnet holes 124 and 126.

[0031] The flux barrier 132 is a gap that extends radially outward from both ends in the longitudinal direction of the magnet hole 122. Each flux barrier 132 is divided into two parts by a bridge to ensure strength, but the bridge is not necessarily required if the required strength can be ensured.

[0032] The flux barrier 134 is a void that extends radially outward from the radially outer ends in the longitudinal direction of the magnet holes 124 and 126.

[0033] The flux barrier 136 is a gap that extends circumferentially from the radially inward end of the magnet holes 124 and 126 in the longitudinal direction, and is located radially inward from the magnet holes 124 and 126, and is formed to connect the magnet holes 124 and 126. The entire hole, including the flux barriers 134 and 136 and the magnet holes 124 and 126, has a U-shape that is open radially outward. The flux barrier 136 is divided into three parts by two bridges to ensure strength, but the bridges are not necessarily required if the required strength can be ensured.

[0034] In this way, the rotor core 120 has flux barriers 132, 134, and 136, which prevents short circuits of magnetic flux between adjacent permanent magnets 160 and suppresses a decrease in the driving torque of the rotating electric machine 10. However, in modified examples, some or all of the flux barriers 132, 134, and 136 may be omitted.

[0035] Note that the configuration of the rotating electric machine 10 shown in Figures 1 to 7 is merely an example, and other configurations are arbitrary as long as they have a skew structure. For example, in this embodiment, there is a two-layer magnet configuration, but there may also be a one-layer magnet configuration or a configuration with three or more layers of magnets.

[0036] The rotating electric machine 10 is a type of synchronous motor. The permanent magnets 160 of the rotor 100 are attracted to the rotating magnetic field generated by applying an alternating current to the coils 240 of the stator 200, and the rotor 100 rotates in synchronization with the rotational speed of the rotating magnetic field. At this time, the rotating magnetic field is concentrated on the teeth 224 located between the slots 222 of the stator 200, and the permanent magnets 160 are attracted to the teeth 224. Since the teeth 224 are formed with equal spacing in the circumferential direction, the driving torque generated in the rotor 100 differs depending on whether the area is facing the teeth 224 or not, and this causes torque ripple.

[0037] In this embodiment, in order to reduce such torque ripple, the rotor 100 has a skew structure (hereinafter also simply referred to as skew). That is, as shown in Figures 5 to 7, the rotor core 120 is divided into a first core 140, a second core 145, a third core 150, etc., in the direction along the axis X, and the first core 140 is shifted relative to the second core 145 by a skew angle (for example, 1 / 4 of 360 / 48) to the first side in the circumferential direction. The third core 150 is shifted relative to the second core 145 by a skew angle (for example, 1 / 4 of 360 / 48) to the second side in the circumferential direction.

[0038] In this embodiment, the skew angle is arbitrary as long as the permanent magnets 160 (especially the permanent magnets 160 in the magnet holes 124 and 126) partially overlap when viewed in the axial direction between adjacent core blocks in the axial direction.

[0039] By introducing skew into the rotor core 120, the permanent magnets 160 of the first core 140, the second core 145, and the third core 150 are also shifted by a skew angle in the circumferential direction. In this case, the permanent magnets 160 in the magnet hole 122 have their pole surfaces aligned in the circumferential direction, so the amount of displacement of the pole surfaces due to skew (the amount of displacement in the direction perpendicular to the pole surface) is small. However, the permanent magnets 160 in the other magnet holes 124 and 126 have their pole surfaces aligned in the radial direction, so the amount of displacement of the pole surfaces due to skew is large. In other words, permanent magnets 160 arranged in a orientation where the radial component is larger than the circumferential component when viewed in the axial direction will experience a larger amount of displacement of their pole surfaces due to skew.

[0040] When the magnetic pole planes are misaligned, a magnetic path is created in the area where the permanent magnet 160 of the first core 140 and the permanent magnet 160 of the second core 145 overlap when viewed in the axial direction, short-circuiting one magnetic pole (e.g., N pole) of the permanent magnet 160 of the first core 140 and the other magnetic pole (e.g., S pole) of the permanent magnet 160 of the second core 145. The magnetic flux passing through this magnetic path (hereinafter also referred to as "short-circuit magnetic flux") causes irreversible demagnetization (hereinafter simply referred to as "demagnetization") to the permanent magnet 160 of the first core 140 and the permanent magnet 160 of the second core 145. When demagnetization occurs to the permanent magnet 160 of the first core 140 and the permanent magnet 160 of the second core 145, the magnetic flux generated by the permanent magnet 160 of the first core 140 and the permanent magnet 160 of the second core 145 decreases, and the driving torque generated by the rotating electric machine 10 decreases. This is also true between the permanent magnet 160 of the second core 145 and the permanent magnet 160 of the third core 150.

[0041] The demagnetization rate, which indicates the degree of demagnetization, increases with increasing displacement of the magnetic pole surfaces and skew angle. Furthermore, the demagnetization rate increases with decreasing axial distance between the permanent magnet 160 of the first core 140 and the permanent magnet 160 of the second core 145. The same applies between the permanent magnet 160 of the second core 145 and the permanent magnet 160 of the third core 150.

[0042] In this embodiment, by realizing the magnet cap structure described later, it is possible to prevent the demagnetization rate from becoming large even when the amount of displacement of the magnetic pole surfaces and the skew angle are relatively large. Further characteristic configurations (magnet cap structure) of this embodiment will be described below with reference to Figure 8 and onward.

[0043] Figure 8 is a schematic cross-sectional view showing an example of a magnet cap structure, and is a cross-sectional view of the first core 140 and the second core 145 along line VV in Figure 5. Figure 9 is a cross-sectional view along line AA in Figure 8. Here, the magnet cap structure is explained using the cross-sections of the first core 140 and the second core 145, but the magnet cap structure for the second core 145 and the third core 150 may be similar. That is, the cross-sectional view in Figure 8 can be replaced with the cross-sectional view of the second core 145 and the third core 150. Furthermore, here, the magnet cap structure for the permanent magnet 160 in the magnet hole 126 is explained, but the magnet cap structure for the permanent magnet 160 in the magnet hole 124 may be similar. Also, the same magnet cap structure may be applied to the permanent magnet 160 in the magnet hole 122.

[0044] In this embodiment, magnet caps 71 and 72 are provided between the permanent magnet 160 of the first core 140 and the permanent magnet 160 of the second core 145 in the axial direction.

[0045] The magnetic caps 71 and 72 are formed from a non-magnetic material. For example, the magnetic caps 71 and 72 may be formed from a resin material. This allows the magnetic caps 71 and 72 to function as flux barriers. Therefore, even if the amount of misalignment of the magnetic pole surfaces or the skew angle between the permanent magnets 160 of the first core 140 and the permanent magnets 160 of the second core 145 is relatively large, it is possible to prevent the demagnetization rate from becoming large.

[0046] The magnetic caps 71 and 72 may be joined to the magnetic holes 126. For example, the magnetic caps 71 and 72 may be formed by injecting a resin material (for example, by injection molding) into the magnetic holes 126 in which the permanent magnets 160 are located.

[0047] The magnetic caps 71 and 72 are provided in such a manner that they completely cover the opening of the magnetic hole 126 (the opening at the axial end face), but they may also be provided in such a manner that they cover only a part of the opening. In the latter case, the magnetic caps 71 and 72 may be provided so as to overlap the permanent magnet 160 when viewed in the axial direction.

[0048] In this embodiment, the magnet caps 71 and 72 are provided so as to fit within the magnet holes 126 of the first core 140 and the second core 145. That is, the magnet caps 71 and 72 are provided in such a manner that they do not obstruct the axial contact between the first core 140 and the second core 145. This prevents the axial size of the rotor core 120 from increasing due to the magnet cap structure. In other words, according to this embodiment, the short-circuit magnetic flux (and the resulting demagnetization rate) can be reduced without increasing the axial size of the rotor core 120.

[0049] Furthermore, the magnet caps 71 and 72 have the function of restricting (positioning) the axial position of the permanent magnets 160 (permanent magnets 160 in the magnet holes 126) of the first core 140 and the second core 145, respectively. Specifically, the magnet cap 71 can restrict the axial position of the permanent magnet 160 of the first core 140 by contacting the axial end face of the permanent magnet 160 of the first core 140 in the axial direction. Similarly, the magnet cap 72 can restrict the axial position of the permanent magnet 160 of the second core 145 by contacting the axial end face of the permanent magnet 160 of the second core 145 in the axial direction. Because of these functions, the magnet cap 72 may be provided on the open side of the first core 140 (the side that does not contact other core blocks), as shown in Figure 8.

[0050] Furthermore, the magnetic caps 71 and 72 have the function of preventing the permanent magnet 160 from scattering. This eliminates the need to inject resin material or otherwise fix the permanent magnet 160 separately within the magnetic hole 126.

[0051] Furthermore, as shown in Figure 8, the shape of the magnet hole 126 may differ in the axial range where the magnet caps 71 and 72 are placed compared to the axial range where the permanent magnet 160 is placed. In the example shown in Figure 8, the shape of the magnet hole 126 may be larger in the axial range where the magnet caps 71 and 72 are placed than in the axial range where the permanent magnet 160 is placed. In this case, the bonding strength of the magnet caps 71 and 72 to the rotor core 120 can be increased.

[0052] In this embodiment, the magnetic caps 71 and 72 are preferably arranged in an overlapping manner when viewed in the axial direction. In this case, the magnetic caps 71 and 72 may simply be in contact with each other in the axial direction, but preferably, as shown in Figure 9, they are connected via an axial interlocking fitting. This enables circumferential positioning between the first core 140 and the second core 145 via the magnetic caps 71 and 72. The interlocking fitting may be a press-fit fitting or a non-press-fit fitting.

[0053] In the example shown in Figure 8, the magnetic cap 71 has a protrusion 712, and the magnetic cap 72 has a recess 722, with the protrusion 712 and the recess 722 fitting together. However, the reverse is also possible. That is, the magnetic cap 72 may have a protrusion, and the magnetic cap 71 may have a recess that fits into the protrusion.

[0054] Incidentally, the three-stage V-shaped skew structure shown in Figure 3 is more difficult to implement with a simple structure a positioning mechanism to appropriately achieve the displacement corresponding to the circumferential skew angle of each core compared to the two-stage V-shaped skew structure shown in Figure 4. In other words, with the two-stage V-shaped skew structure shown in Figure 4, the first core 140A and the second core 145A are key-fitted to the shaft 110, and positioning is easy by shifting the circumferential position of the keyway by an angle corresponding to the skew angle.

[0055] In contrast, in this embodiment, the magnetic caps 71 and 72 are connected via a recessed-protrusion fitting, making circumferential positioning easy even in a three-stage V-shaped skew structure as shown in Figure 3. In this embodiment, the rotor core 120 and the shaft 110 do not need to have a key fitting portion.

[0056] In this embodiment, the magnet caps 71 and 72 that connect via the protrusions and recesses may be provided only in the stator core 220 where they are stacked with a skew angle. For example, in the example shown in Figure 3, the magnet caps 71 and 72 that connect via the protrusions and recesses may be provided, in order from top to bottom in Figure 3, between the first core 140 and the second core 145, between the second core 145 and the third core 150, between the third core 150 and the second core 145, and between the second core 145 and the first core 140. Furthermore, magnet caps 71 without the protrusions 712 and magnet caps 72 without the recesses 722 may be provided between the second core 145 and the third core 150.

[0057] Furthermore, in this embodiment, the magnetic caps 71 and 72 that connect via the protrusions and recesses may be provided only for a portion (for example, only one location) of the multiple permanent magnets 160. In this case, the magnetic caps 71 and 72 may be provided only for a portion of the permanent magnets 160 within the magnetic holes 124 and 126. This is because, as described above, the magnetic pole surfaces of the permanent magnets 160 within the magnetic holes 124 and 126 are aligned radially, and the amount of displacement of the magnetic pole surfaces due to skew is large (therefore, the above-mentioned effect of the magnetic caps 71 and 72 becomes more pronounced). In this case, the other permanent magnets 160 may be provided with magnetic caps 71 without the protrusions 712 and magnetic caps 72 without the recesses 722.

[0058] Furthermore, in core blocks stacked with skew angles on both axial sides, a magnet cap 71 may be placed on one axial side and a magnet cap 72 on the other axial side. In this case, magnet caps 71 and 72 can be formed (injection molded) for similar core blocks using a common mold.

[0059] Figures 10 and 11 are explanatory diagrams illustrating various examples of the interlocking shapes of the magnetic caps 71 and 72.

[0060] In the example shown in Figure 10, the protrusion 712 of the magnet cap 71 is in the shape of a rectangular parallelepiped, and the recess 722 of the magnet cap 72 is also in the shape of a rectangular parallelepiped. In this case, the protrusion 712 and recess 722 are not formed along the entire length of the magnet caps 71 and 72, but may be formed only in part. If they are formed only in part, the recess 722 may be in the shape of a through hole. On the other hand, in the example shown in Figure 11, the protrusion 712 of the magnet cap 71 is in the shape of a cylindrical shape, and the recess 722 of the magnet cap 72 is also in the shape of a cylindrical shape. In this case, the recess 722 may be in the shape of a through hole. Thus, the shape of the protrusions and recesses is arbitrary, as long as they fit together.

[0061] Although each embodiment has been described in detail above, the invention is not limited to any particular embodiment, and various modifications and changes are possible within the scope described in the claims. Furthermore, it is possible to combine all or more of the components of the embodiments described above.

[0062] For example, in the embodiment described above, magnet caps 71 and 72 are provided on the side where the core blocks abut each other. However, only the magnet cap with the convex portion of magnet caps 71 and 72 may be provided. In this case, the magnet cap may be provided in such a manner that the convex portion of the magnet cap fits into the other magnet hole. In this case as well, the convex portion and the magnet hole can achieve the same positioning function as the fitting of the convex portion and concave portion described above.

[0063] Furthermore, although the magnet caps 71 and 72 are separate in the above-described embodiment, they may be integrated. In this case, the integrated magnet caps 71 and 72 can be assembled by inserting them into one of the magnet holes 126 of the first core 140 and the second core 145 after molding, and then inserting them into the other magnet hole 126.

[0064] Furthermore, the following additional information is disclosed regarding the above-mentioned embodiment.

[0065] [Note 1] A rotor for a rotating electric machine having a skewed structure, A rotor core including a first core and a second core stacked in the axial direction, A first magnet is placed in the first magnet hole of the first core, A second magnet is placed in the second magnet hole of the second core, Formed from a non-magnetic material, the magnet hole comprises a non-magnetic member in at least one of the first magnet hole and the second magnet hole, The first core and the second core are in contact in the axial direction while being offset from each other by a skew angle, such that the first magnet hole and the second magnet hole partially overlap when viewed in the axial direction. The non-magnetic member is a rotor for a rotating electric machine, positioned axially between the first magnet and the second magnet.

[0066] [Note 2] The non-magnetic member has a convex portion that protrudes axially from the one magnet hole while axially contacting the magnet in the one magnet hole. The rotor for a rotating electric machine as described in Appendix 1, wherein the protrusion is housed within the other of the first and second magnet holes.

[0067] [Note 3] The non-magnetic member is A first cap member is provided at the end of the first magnet hole on the second core side, which abuts the first magnet in the axial direction. The second magnet hole includes a second cap member that abuts the second magnet in the axial direction at the end on the first core side, Rotor for a rotating electric machine according to Appendix 1 or 2, wherein either the first cap member or the second cap member has the protrusion, and the other of the first cap member or the second cap member has an axial recess for receiving the protrusion.

[0068] [Note 4] A third cap member having the same shape as the second cap member is provided at the end of the first magnet hole that is furthest from the second core in the axial direction, The rotor for a rotating electric machine according to Appendix 3, further comprising a fourth cap member having the same form as the first cap member at the end of the second magnet hole that is axially furthest from the first core.

[0069] [Note 5] The rotor for a rotating electric machine as described in any one of the appendices 1 to 4, wherein the first magnet and the second magnet have a longitudinal direction in which, when viewed in the axial direction, the radial component is greater than the circumferential component. [Explanation of Symbols]

[0070] 10 Rotating electric machine, 100 Rotor, 120 Rotor core, 140 First core, 145 Second core, 126 Magnet hole (First magnet hole, Second magnet hole), 160 Permanent magnet (First magnet, Second magnet), 71 Magnet cap (Non-magnetic material, First cap material), 72 Magnet cap (Non-magnetic material, Second cap material), 712 Protrusion, 722 Recess

Claims

1. A rotor for a rotating electric machine having a skewed structure, A rotor core including a first core and a second core stacked in the axial direction, A first magnet is placed in the first magnet hole of the first core, A second magnet is placed in the second magnet hole of the second core, Formed from a non-magnetic material, the magnet hole comprises a non-magnetic member in at least one of the first magnet hole and the second magnet hole, The first core and the second core are in contact in the axial direction while being offset from each other by a skew angle, such that the first magnet hole and the second magnet hole partially overlap when viewed in the axial direction. The non-magnetic member is a rotor for a rotating electric machine, positioned axially between the first magnet and the second magnet.

2. The non-magnetic member has a convex portion that protrudes axially from the one magnet hole while axially contacting the magnet in the one magnet hole. The rotor for a rotating electric machine according to claim 1, wherein the protrusion is housed within the other of the first and second magnet holes.

3. The non-magnetic member is A first cap member is provided at the end of the first magnet hole on the second core side, which abuts the first magnet in the axial direction. The end of the second magnet hole on the first core side includes a second cap member that abuts the second magnet in the axial direction, Rotor for a rotating electric machine according to claim 2, wherein either the first cap member or the second cap member has the protrusion, and the other of the first cap member or the second cap member has an axial recess for receiving the protrusion.

4. The rotor for a rotating electric machine according to any one of claims 1 to 3, wherein the first magnet and the second magnet have a longitudinal direction in which, when viewed in the axial direction, the radial component is greater than the circumferential component.

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