rotor

Abstract

To provide a rotor which can reliably restrict a slot inner portion of a conductor from moving to an outer side in a radial direction inside a slot before the slot inner portion is fixed to the slot.SOLUTION: In a rotor 100, a rotor core 10 is formed such that electromagnetic steel plates 12 and core sheets 13 are laminated in an axial direction (Z-direction). In a first slot opening 12a of each of the electromagnetic steel plates 12, a slot inner portion 21 is disposed on an inner side (R1-side) in a radial direction (R-direction), and a gap 12b is formed on an outer side (R2-side) in the radial direction (R-direction). Further, a second slot opening 13a of each of the core sheets 13 is shaped such that the slot inner portion 21 is in proximity to the second slot opening 13a on the inner side (R1-side) and the outer side (R2-side) in the radial direction (R-direction).SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a rotor. [Background technology]

[0002] BACKGROUND ART Conventionally, a rotor is known that includes a rotor core including a plurality of slots and a plurality of conductors that include inner-slot portions housed in each of the plurality of slots and through which induced current flows (see, for example, Patent Document 1).

[0003] The above-mentioned Patent Document 1 discloses a rotor including a rotor core having a plurality of slots and a plurality of copper bars (conductors) including portions accommodated in each of the plurality of slots (hereinafter referred to as "intra-slot portions"). In the rotor described in the above-mentioned Patent Document 1, the intra-slot portions are arranged radially inward within the slots. The copper bars are formed by stacking six copper plates. On the axial outer side of the rotor core, three of the six copper plates constituting the copper bar are bent to one side in the circumferential direction of the rotor core, and the remaining three copper plates are bent to the other side in the circumferential direction. As a result, the ends of the copper bars adjacent in the circumferential direction are in axial contact with each other. In addition, an aluminum bar formed by aluminum die-casting is arranged on the radial outer side of the slot where the intra-slot portions are not arranged. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5313552 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the rotor described in Patent Document 1, although the ends of adjacent copper bars (conductors) in the circumferential direction are in axial contact with each other before aluminum die-casting (casting), there is space within the slots radially outside the slot interiors for placing the aluminum bars. That is, when a radially outward force acts on the copper bars, sufficient frictional resistance must be generated between the ends of the copper bars to prevent the copper bars from moving radially outward. Whether sufficient frictional resistance occurs between the ends of the copper bars depends on the degree of axial contact between the ends of the copper bars and the surface roughness of the copper bars, and is therefore uncertain. Therefore, it is possible that the radially outward movement of the slot interiors may not be prevented before aluminum die-casting is completed and the slot interiors are fixed to the slots. Furthermore, if the slot interiors move radially outward within the slots, eddy currents are likely to be generated in the conductors, resulting in increased eddy current loss when the rotor is used as part of a rotating electric machine. Furthermore, if the radial positions of the slot interiors differ among slots, the rotor's weight becomes unbalanced in the circumferential direction, resulting in increased noise and vibration when the rotor is used as part of a rotating electric machine. Therefore, there is a demand for a rotor that can reliably restrict the in-slot portion of the conductor from moving radially outward within the slot before the in-slot portion is fixed to the slot.

[0006] The present invention has been made to solve the above-mentioned problems, and one object of the present invention is to provide a rotor that can reliably restrict the in-slot portion of the conductor from moving radially outward within the slot before the in-slot portion is fixed to the slot. [Means for solving the problem]

[0007] To achieve the above object, one aspect of the present invention provides a rotor comprising: a rotor core including a plurality of slots extending axially and spaced at predetermined intervals in the circumferential direction; and a plurality of conductors through which induced currents flow, each conductor including an inner-slot portion accommodated in each of the plurality of slots and an outer-slot portion axially outside the slots. The rotor core is axially stacked with electromagnetic steel sheets having first slot openings constituting a portion of each of the plurality of slots and a core sheet disposed at at least one axial end of the rotor core and having second slot openings constituting a portion of each of the plurality of slots. The first slot openings of the electromagnetic steel sheets have inner-slot portions disposed radially inside and gaps formed radially outside, and the second slot openings of the core sheet have a shape in which the inner-slot portions are close to the second slot openings on both the radial inside and outside. Note that, in this specification, the term "close to" encompasses both a shape in which the inner-slot portions are close to but spaced from each other and a shape in which the inner-slot portions are in contact with each other.

[0008] In a rotor according to one aspect of the present invention, as described above, the rotor core is formed by axially stacking electromagnetic steel sheets having first slot openings that form part of each of the plurality of slots, and core sheets that are disposed at at least one axial end of the rotor core and have second slot openings that form part of each of the plurality of slots. The first slot openings of the electromagnetic steel sheets have intra-slot portions disposed radially inside and gaps formed radially outside. The second slot openings of the core sheets have a shape such that the intra-slot portions are close to the second slot openings on both the inside and outside in the radial direction. As a result, the intra-slot portions are disposed radially inside the first slot openings of the electromagnetic steel sheets, and gaps are formed radially outside, resulting in the intra-slot portions being disposed radially inside within the slots. Furthermore, with the intra-slot portion positioned radially inward within the slot, the second slot opening of the core sheet has a shape in which the intra-slot portion is close to the second slot opening on both the radially inner and outer sides, so that the intra-slot portion is sandwiched between the second slot openings from the radially inner and outer sides, thereby reliably restricting radial movement of the intra-slot portion by the second slot opening that is close to the intra-slot portion in the radial direction. As a result, it is possible to reliably restrict radial outward movement of the intra-slot portion of the conductor before it is fixed to the slot. [Effects of the Invention]

[0009] According to the present invention, as described above, a rotor can be provided that can reliably restrict the in-slot portion of the conductor from moving radially outward within the slot before the in-slot portion is fixed to the slot. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a perspective view of a rotor according to an embodiment of the present invention; [Figure 2] FIG. 2 is a plan view showing a rotor core and multiple conductors of a rotor according to an embodiment of the present invention. [Figure 3] 3 is a cross-sectional view taken along line 900-900 in FIG. 2 (a cross-sectional view of a rotor according to an embodiment of the present invention as seen in the circumferential direction). [Figure 4] 1 is a plan view showing electromagnetic steel plates that form a rotor core of a rotor according to an embodiment of the present invention. FIG. [Figure 5] 1 is a plan view showing a core sheet that constitutes a rotor core of a rotor according to an embodiment of the present invention. FIG. [Figure 6] FIG. 5 is a partially enlarged plan view of FIG. [Figure 7] FIG. 6 is a partially enlarged plan view of FIG. 5. [Figure 8] 5A to 5C are diagrams showing a manufacturing flow of a rotor according to an embodiment of the present invention. [Figure 9] 5A to 5C are diagrams for explaining an electromagnetic steel sheet lamination step in the manufacturing flow of the rotor according to the embodiment of the present invention. [Figure 10] 5A to 5C are diagrams for explaining a conductor insertion step in the manufacturing flow of the rotor according to the embodiment of the present invention. [Figure 11] FIG. 10 is a cross-sectional view of a rotor according to a first modified example of an embodiment of the present invention, viewed in the circumferential direction. [Figure 12] FIG. 10 is a cross-sectional view of a rotor according to a second modified example of an embodiment of the present invention, viewed in the circumferential direction. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0012] [Rotor configuration] The configuration of a rotor 100 according to one embodiment of the present invention will be described with reference to FIGS.

[0013] In the following description, the axial, radial, and circumferential directions of the rotor 100 are referred to as the Z direction, R direction, and C direction, respectively. One side and the other side in the axial direction (Z direction) are referred to as the Z1 side and the Z2 side, respectively. The inner and outer sides in the radial direction (R direction) are referred to as the R1 side and the R2 side, respectively.

[0014] As shown in Fig. 1, the rotor 100 is used together with a stator (not shown) as part of a rotating electric machine (not shown). The stator is disposed on the R2 side of the rotor 100 so as to face the rotor 100. In other words, the rotor 100 is configured as part of an inner rotor type rotating electric machine. The rotating electric machine is, for example, a motor, a generator, or a motor / generator.

[0015] The rotor 100 includes a rotor core 10. The rotor core 10 has a cylindrical shape with a central axis 90 along the Z direction. As will be described later, the rotor core 10 is formed by stacking a plurality of electromagnetic steel plates 12 (see FIG. 3) and a plurality of core sheets 13 (see FIG. 3) in the Z direction.

[0016] 2, the rotor core 10 includes a plurality of slots 11. The plurality of slots 11 are provided at predetermined intervals in the circumferential direction (C direction) in the R2 side portion of the rotor core 10. Each of the plurality of slots 11 extends along the axial direction (Z direction) so as to penetrate the rotor core 10 in the axial direction.

[0017] The rotor 100 includes a plurality of conductors 20. Each of the plurality of conductors 20 is formed of copper or a copper alloy. The plurality of conductors 20 are configured so that, when the rotor 100 is used as part of a rotating electric machine, an induced current flows through the plurality of conductors 20 when power is supplied to windings arranged in the stator.

[0018] As shown in FIG. 3, each of the plurality of conductors 20 is formed in a plate shape. The plurality of conductors 20 includes an in-slot portion 21 and an out-slot portion 22. Each of the plurality of conductors 20 is composed of a single conductor. That is, the in-slot portion 21 and the out-slot portion 22 are integrally formed. The in-slot portion 21 is configured to extend along the Z direction. The in-slot portion 21 is housed in each of the plurality of slots 11. The out-slot portion 22 is disposed outside the slot 11 in the axial direction (Z direction).

[0019] As shown in FIG. 1, the rotor 100 includes a ring member 30. The ring member 30 has an annular shape. The ring member 30 is made of aluminum or an aluminum alloy. As shown in FIG. 3, the ring member 30 is formed by casting so as to cover the plurality of conductors 20 on both outer sides in the axial direction (Z direction) of the rotor core 10. As a result, the ring member 30 electrically connects the outside-slot portions 22 to each other.

[0020] (Configuration for restricting radial outward movement of conductor) The rotor core 10 is formed by stacking in the axial direction (Z direction) electromagnetic steel sheets 12 having first slot openings 12a that constitute a portion of each of the plurality of slots 11, and core sheets 13 that are arranged at at least one end 10a (Z1 side) of the rotor core 10 in the axial direction (Z direction) and have second slot openings 13a that constitute a portion of each of the plurality of slots 11. An inner-slot portion 21 is arranged on the inner side (R1 side) of the first slot opening 12a of the electromagnetic steel sheets 12 in the radial direction (R direction), and a void portion 12b is formed on the outer side (R2 side) of the first slot opening 12a in the radial direction (R direction). The second slot opening 13a of the core sheet 13 has a shape in which the inner-slot portion 21 is close to the second slot opening 13a on the inner side (R1 side) and the outer side (R2 side) in the radial direction (R direction).

[0021] Specifically, the rotor core 10 is formed by stacking a plurality of electromagnetic steel sheets 12 and a plurality of core sheets 13 in the Z direction. As shown in FIG. 4, the electromagnetic steel sheets 12 have an annular shape when viewed in the Z direction. The electromagnetic steel sheets 12 have a plurality of first slot openings 12a. The plurality of first slot openings 12a are provided at predetermined intervals in the C direction in an R2-side portion of the electromagnetic steel sheets 12. As shown in FIG. 5, the core sheet 13 has a plurality of second slot openings 13a. The plurality of second slot openings 13a are provided at predetermined intervals in the C direction in an R2-side portion of the core sheet 13. The core sheet 13 may be made of a magnetic material (for example, the same material as the electromagnetic steel sheets 12) or a non-magnetic material. As shown in FIG. 3, the first slot openings 12a of the electromagnetic steel sheets 12 and the second slot openings 13a of the core sheet 13 are continuous in the Z direction to form slots 11 extending in the Z direction. When viewed in the Z direction, the second slot opening 13a overlaps with the R1-side portion of the first slot opening 12a. That is, the width W11 of the first slot opening 12a in the R direction is larger than the width W12 of the second slot opening 13a in the R direction. In the first slot opening 12a of the electromagnetic steel sheet 12, an intra-slot portion 21 is disposed on the R1 side, and a void portion 12b is formed on the R2 side. As shown in FIG. 6, the first slot opening 12a has a semi-open slot shape. That is, the width of the R2-side end of the void portion 12b in the C direction is smaller than the width of the portion of the void portion 12b other than the R2-side end in the C direction. And, as shown in FIG. 3, the intra-slot portion 21 is disposed over substantially the entire R direction of the second slot opening 13a of the core sheet 13. That is, the R1 side surface of the second slot opening 13a of the core sheet 13 is close in the R direction to the R1 side surface of the slot inner portion 21. Also, the R2 side surface of the second slot opening 13a of the core sheet 13 is close in the R direction to the R2 side surface of the slot inner portion 21.

[0022] As a result, in the first slot opening 12a of the electromagnetic steel sheet 12, the slot inner portion 21 is positioned on the inner side (R1 side) in the radial direction (R direction), and a gap portion 12b is formed on the outer side (R2 side) in the radial direction (R direction), so that the slot inner portion 21 is positioned on the inner side (R1 side) in the radial direction (R direction) within the slot 11. When the in-slot portion 21 is disposed on the inner side (R1 side) in the radial direction (R direction) within the slot 11, the second slot opening 13a of the core sheet 13 has a shape in which the in-slot portion 21 is close to the second slot opening 13a on the inner side (R1 side) and the outer side (R2 side) in the radial direction (R direction). This sandwiches the in-slot portion 21 between the second slot opening 13a from the inner side (R1 side) and the outer side (R2 side) in the radial direction (R direction). This allows the movement of the in-slot portion 21 in the radial direction (R direction) to be reliably restricted by the second slot opening 13a, which comes into contact with the in-slot portion 21 in the radial direction (R direction). As a result, movement of the in-slot portion 21 of the conductor 20 to the outer side (R2 side) in the radial direction (R direction) within the slot 11 can be reliably restricted.

[0023] Furthermore, since the movement of the slot inner portion 21 in the radial direction (R direction) can be reliably restricted by the second slot opening 13a of the core sheet 13, which is part of the rotor core 10, there is no need to separately provide a dedicated jig or device to hold the slot inner portion 21 at a predetermined position within the slot 11.

[0024] 3, the core sheet 13 is disposed at least at both end portions 10a in the axial direction (Z direction) of the rotor core 10. The second slot opening 13a of the core sheet 13 has a shape such that the slot inner portion 21 contacts the second slot opening 13a on the inner side (R1 side) and outer side (R2 side) in the radial direction (R direction).

[0025] Specifically, a plurality of core sheets 13 are stacked on top of one another at the Z1-side end 10a and the Z2-side end 10a of the rotor core 10. As shown in FIG. 7 , the intra-slot portion 21 has a generally rectangular shape when viewed in the Z direction. The second slot opening 13a also has a generally rectangular shape when viewed in the Z direction. The R1-side surface of the intra-slot portion 21 contacts the R1-side surface of the second slot opening 13a. The R2-side surface of the intra-slot portion 21 contacts the R2-side surface of the second slot opening 13a. That is, the width W13 of the intra-slot portion 21 in the R direction is equal to the width W12 of the second slot opening 13a in the R direction. One side surface of the intra-slot portion 21 in the C direction is closely spaced from one side surface of the second slot opening 13a in the C direction. Furthermore, the other surface of the intra-slot portion 21 in the C direction is closely spaced from the other surface of the second slot opening 13a in the C direction. That is, the width W23 of the intra-slot portion 21 in the C direction is approximately equal to the width W22 of the second slot opening 13a in the C direction. In other words, the second slot opening 13a of the core sheet 13 has a shape in which the intra-slot portion 21 is closely spaced from the second slot opening 13a on one and the other sides in the circumferential direction (C direction). As shown in FIG. 3, the R1-side surface of the first slot opening 12a is spaced from the R1-side surface of the intra-slot portion 21. That is, the R1-side surface of the first slot opening 12a is located closer to the R1 side than the R1-side surface of the second slot opening 13a.

[0026] As a result, the second slot openings 13a of the core sheet 13 arranged at least at both end portions 10a in the axial direction (Z direction) of the rotor core 10 have a shape such that the slot inner portions 21 contact the second slot openings 13a on the inside (R1 side) and outside (R2 side) in the radial direction (R direction).Therefore, when the ring members 30 covering the multiple slot outer portions 22 on both sides in the axial direction (Z direction) of the rotor core 10 are formed by casting, the molten ring members 30 can be prevented from penetrating (leaking out) through the second slot openings 13a into the gap portions 12b formed on the outside (R2 side) in the radial direction (R direction) of the first slot openings 12a. Since the gap 12b is formed on the outer side (R2 side) in the radial direction (R direction) of the first slot opening 12a, if the molten ring member 30 enters the gap 12b of the first slot opening 12a, the material of the ring member 30 that has solidified in the gap 12b of the first slot opening 12a will generate eddy currents in the solidified material of the ring member 30 when the rotor 100 is used as part of a rotating electric machine, resulting in increased eddy current loss. Furthermore, if the amount of material of the ring member 30 that has entered the gap 12b of the first slot opening 12a and solidified and the solidified position differ for each slot 11, the weight of the rotor 100 will become unbalanced in the circumferential direction, resulting in increased noise and vibration when the rotor 100 is used as part of a rotating electric machine.

[0027] Furthermore, the second slot opening 13a of the core sheet 13 has a shape such that the in-slot portion 21, which has an interference in the radial direction (R direction) with respect to the second slot opening 13a and is press-fitted into the second slot opening 13a, contacts the second slot opening 13a on the inner side (R1 side) and outer side (R2 side) in the radial direction (R direction). That is, the in-slot portion 21, which has a width in the R direction larger than the width of the second slot opening 13a in the R direction, is press-fitted into the second slot opening 13a and inserted therein. Note that in the rotor 100, the second slot opening 13a into which the in-slot portion 21 is press-fitted is not bent (in the Z direction).

[0028] As a result, by press-fitting the in-slot portion 21, which has an interference in the radial direction (R direction) with respect to the second slot opening 13a, into the second slot opening 13a, the second slot opening 13a can be easily configured to have a shape in which the in-slot portion 21 contacts the second slot opening 13a on the inner side (R1 side) and outer side (R2 side) in the radial direction (R direction). As a result, when the ring member 30 covering the multiple out-slot portions 22 is formed by casting, it is possible to more reliably prevent the molten ring member 30 from entering (leaking out of) the gap portion 12b of the first slot opening 12a through the second slot opening 13a.

[0029] Furthermore, the core sheets 13 are arranged not only at both end portions 10a in the axial direction (Z direction) of the rotor core 10 but also in portions other than the both end portions 10a in the axial direction (Z direction) of the rotor core 10. Specifically, the core sheets 13 are arranged not only at the end portion 10a on the Z1 side and the end portion 10a on the Z2 side of the rotor core 10 but also at the central portion 10b in the Z direction of the rotor core 10. In the rotor 100, the multiple core sheets 13 are arranged so as to be stacked on top of each other in the central portion 10b of the rotor core 10.

[0030] This allows the second slot openings 13a to reliably restrict movement of the in-slot portions 21 in the radial direction (R direction) not only at both end portions 10a in the axial direction (Z direction) of the rotor core 10 but also at portions other than the both end portions 10a in the axial direction (Z direction) of the rotor core 10. As a result, when the rotor 100 is used as part of a rotating electric machine, it is possible to prevent the in-slot portions 21 from bending outward (toward the R2 side) in the radial direction (R direction) due to centrifugal force acting on the in-slot portions 21.

[0031] [Rotor manufacturing method] A method for manufacturing the rotor 100 according to one embodiment of the present invention will be described with reference to FIGS. 3 to 5 and 8 to 10.

[0032] (Electromagnetic steel sheet forming process) First, in step S1, an electromagnetic steel sheet forming process is performed as shown in Fig. 8. The electromagnetic steel sheet forming process (S1) is a process of forming a plurality of electromagnetic steel sheets 12 having a plurality of first slot openings 12a as shown in Fig. 4. The electromagnetic steel sheet forming process (S1) is performed by, for example, pressing.

[0033] (Core sheet molding process) Next, as shown in Fig. 8, a core sheet forming step is performed in step S2. The core sheet forming step (S2) is a step of forming a plurality of core sheets 13 having a plurality of second slot openings 13a, as shown in Fig. 5. The core sheet forming step (S2) is performed by, for example, press working. Note that the order of the electromagnetic steel sheet forming step (S1) and the core sheet forming step (S2) may be reversed.

[0034] (Lamination process) Next, in step S3, a stacking process is performed as shown in Fig. 8. The stacking process (S3) is a process of stacking a plurality of electromagnetic steel sheets 12 having a plurality of first slot openings 12a and a plurality of core sheets 13 having a plurality of second slot openings 13a in the Z direction as shown in Fig. 9.

[0035] (Conductor insertion process) Next, as shown in Fig. 8, a conductor insertion process is performed in step S4. As shown in Fig. 10, the conductor insertion process (S4) is a process of inserting an in-slot portion 21 into a slot 11 formed by laminating a plurality of electromagnetic steel sheets 12 and a plurality of core sheets 13 together, with a plurality of first slot openings 12a and a plurality of second slot openings 13a. The conductor insertion process (S4) is performed by press-fitting. As a result, as shown in Fig. 3, in the first slot opening 12a of the electromagnetic steel sheet 12, the in-slot portion 21 is disposed on the inner side (R1 side) in the radial direction (R direction), and a void portion 12b is formed on the outer side (R2 side) in the radial direction (R direction), and the second slot opening 13a of the core sheet 13 has the in-slot portion 21 adjacent to the second slot opening 13a on the inner side (R1 side) and the outer side (R2 side) in the radial direction (R direction).

[0036] (Ring component casting process) Next, in step S5, a ring member casting process is performed as shown in Fig. 8. As shown in Fig. 3, the ring member casting process (S5) is a process of casting a ring member 30 so as to cover the plurality of conductors 20 on both outer sides of the rotor core 10 in the axial direction (Z direction).

[0037] [Variations] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims rather than the above description of the embodiments, and further includes all modifications (variations) within the meaning and scope of the claims.

[0038] For example, in the above embodiment, the core sheet 13 is disposed at the Z-direction central portion 10b of the rotor core 10 in addition to the Z1-side end portion 10a and the Z2-side end portion 10a of the rotor core 10, but the present invention is not limited to this. In the present invention, the core sheet 13 may be disposed at a portion of the rotor core 10 other than the Z1-side end portion 10a, the Z2-side end portion 10a, and the central portion 10b, in addition to the Z1-side end portion 10a and the Z2-side end portion 10a of the rotor core 10. In this case, the core sheet 13 may be disposed at a plurality of portions of the rotor core 10 other than the Z1-side end portion 10a, the Z2-side end portion 10a, and the central portion 10b.

[0039] Furthermore, in the above embodiment, an example has been shown in which the core sheet 13 is arranged not only at both end portions 10a in the axial direction (Z direction) of the rotor core 10 but also at portions other than both end portions 10a in the axial direction (Z direction) of the rotor core 10, but the present invention is not limited to this. In the present invention, as in a rotor 200 of a first modified example shown in Fig. 11, the core sheet 13 may be arranged only at both end portions 10a in the axial direction (Z direction) of the rotor core 210.

[0040] Furthermore, in the above embodiment, an example has been described in which the second slot opening 13a into which the slot inner portion 21 is press-fitted is not bent. However, the present invention is not limited to this. In the present invention, the second slot opening 313a into which the slot inner portion 21 is press-fitted may be bent, as in a rotor 300 of a second modified example shown in Fig. 12. Specifically, as shown in Fig. 12, in a rotor core 310, the second slot opening 313a of the core sheet 313 is bent in a state in which the slot inner portion 21, which has an interference in the radial direction (R direction) with respect to the second slot opening 313a and is press-fitted into the second slot opening 313a, is in contact with the second slot opening 313a on the inner side (R1 side) and the outer side (R2 side) in the radial direction (R direction). As a result, even when the slot inner portion 21 having a clamping margin in the radial direction (R direction) relative to the second slot opening 13a large enough to cause the second slot opening 313a to bend is pressed into the second slot opening 313a, the slot inner portion 21 can be configured to have a shape that contacts the second slot opening 313a on the inside (R1 side) and outside (R2 side) in the radial direction (R direction).

[0041] In the above embodiment, the second slot opening 13a of the core sheet 13 has a shape in which the inner-slot portion 21, which has an interference in the radial direction (R direction) with respect to the second slot opening 13a and is press-fitted into the second slot opening 13a, contacts the second slot opening 13a on the inner side (R1 side) and outer side (R2 side) in the radial direction (R direction). However, the present invention is not limited to this. In the present invention, the second slot opening 13a of the core sheet 13 may be configured to have a shape in which the inner-slot portion 21, which is inserted into the second slot opening 13a by a method other than press-fitting (for example, shrink fitting, chill fitting, etc.), contacts the second slot opening 13a on the inner side (R1 side) and outer side (R2 side) in the radial direction (R direction).

[0042] In the above embodiment, the core sheet 13 is disposed at least at both end portions 10a in the axial direction (Z direction) of the rotor core 10, but the present invention is not limited to this. In the present invention, the core sheet 13 may be disposed only at the end portion 10a on one side (Z1 side) in the axial direction (Z direction) of the rotor core 10.

[0043] In the above embodiment, the second slot opening 13a of the core sheet 13 has a shape in which the intra-slot portion 21 contacts the second slot opening 13a on the inner side (R1 side) and outer side (R2 side) in the radial direction (R direction) and the intra-slot portion 21 is closely spaced from the second slot opening 13a on one side and the other side in the circumferential direction (C direction). However, the present invention is not limited to this. In the present invention, the second slot opening 13a of the core sheet 13 may have a shape in which the intra-slot portion 21 contacts the second slot opening 13a on the inner side (R1 side) and outer side (R2 side) in the radial direction (R direction) and the intra-slot portion 21 contacts the second slot opening 13a on one side and the other side in the circumferential direction (C direction). In this case, compared to when the slot inner portion 21 is closely spaced from the second slot opening 13a on one side and the other side in the circumferential direction (direction C), when the ring member 30 covering the multiple slot outer portions 22 is formed by casting, it is possible to reliably prevent the molten ring member 30 from penetrating (leaking out) into the first slot opening 12a through the second slot opening 13a.

[0044] In the above embodiment, the second slot opening 13a of the core sheet 13 has a shape in which the slot inner portion 21 contacts the second slot opening 13a on the inner side (R1 side) and outer side (R2 side) in the radial direction (R direction), but the present invention is not limited to this. In the present invention, the second slot opening 13a of the core sheet 13 may have a shape in which the slot inner portion 21 is spaced close to the second slot opening 13a on the inner side (R1 side) and outer side (R2 side) in the radial direction (R direction).

[0045] In the above embodiment, an example has been shown in which multiple core sheets 13 are arranged to be stacked on top of each other at the Z1-side end 10a, the Z2-side end 10a, and the central portion 10b of the rotor core 10, but the present invention is not limited to this. In the present invention, only one core sheet 13 may be arranged in the portion of the rotor core 10 in the Z direction where the core sheet 13 is arranged, instead of multiple core sheets 13.

[0046] In the above embodiment, the slot inner portion 21 and the second slot opening 13a have a substantially rectangular shape when viewed in the Z direction, but the present invention is not limited to this. In the present invention, the slot inner portion 21 and the second slot opening 13a may have a shape other than a substantially rectangular shape when viewed in the Z direction.

[0047] In the above embodiment, the first slot opening 12a has a semi-open slot shape, but the present invention is not limited to this. In the present invention, the first slot opening 12a may have a fully open slot shape or a closed slot shape. [Explanation of symbols]

[0048] 10, 210, 310... rotor core, 10a... end (in the axial direction of the rotor core), 11... slot, 12... electromagnetic steel sheet, 12a... first slot opening, 12b... gap, 13, 313... core sheet, 13a, 313a... second slot opening, 20... conductor, 21... inner slot portion, 22... outer slot portion, 30... ring member, 100, 200, 300... rotor

Claims

1. a rotor core including a plurality of slots extending along the axial direction and provided at predetermined intervals in the circumferential direction; a plurality of conductors through which an induced current flows, the conductors including an in-slot portion housed in each of the plurality of slots and an out-slot portion disposed outside the slots in the axial direction; the rotor core is formed by stacking in the axial direction electromagnetic steel plates each having a first slot opening that constitutes a part of each of the plurality of slots, and core sheets each being disposed at at least one end of the rotor core in the axial direction and each having a second slot opening that constitutes a part of each of the plurality of slots, the first slot opening of the electromagnetic steel sheet has an inner slot portion disposed on an inner side in a radial direction and a gap portion formed on an outer side in the radial direction, A rotor, wherein the second slot opening of the core sheet has a shape such that the slot inner portion is close to the second slot opening on the inner and outer sides in the radial direction.

2. The rotor core further includes ring members formed by casting on both sides in the axial direction of the rotor core so as to cover the plurality of out-of-slot portions and electrically connect the out-of-slot portions to each other, the core sheets are disposed at least at both end portions of the rotor core in the axial direction, The rotor according to claim 1 , wherein the second slot opening of the core sheet has a shape such that the slot inner portion contacts the second slot opening on the inner and outer sides in the radial direction.

3. 3. The rotor according to claim 2, wherein the second slot opening of the core sheet has a shape such that when the slot inner portion having an interference with the second slot opening in the radial direction is press-fitted into the second slot opening, the slot inner portion contacts the second slot opening on the inside and outside in the radial direction.

4. 4. The rotor according to claim 3, wherein the second slot opening of the core sheet is bent in a state where the slot inner portion, which has an interference with the second slot opening in the radial direction and is press-fitted into the second slot opening, is in contact with the second slot opening on the inner and outer sides in the radial direction.

5. The rotor according to any one of claims 2 to 4, wherein the core sheet is arranged not only at both ends of the rotor core in the axial direction, but also at portions of the rotor core other than the both ends in the axial direction.

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