Rotary electric machine

Abstract

To securely fix a cover member covering a coil end part, while preventing or minimizing an increase in radial size of a rotary electric machine as a whole.SOLUTION: A rotary electric machine comprises: an iron core having a plurality of tooth parts; a coil wire which is wound around the iron core in such a manner that it is inserted into a slot, and which forms a coil end part on an axially outer side with respect to an axial end surface of the iron core; a first cover member which covers the coil end part from the axially outer side, a radially inner side, and a radially outer side; a second cover member which covers the axial end surface of the iron core; and a coolant space between the first cover member and the second cover member. In cross-sectional view of a plane passing through a central axis of the iron core, the first cover member and the second cover member are coupled to each other: via a first coupling part on the radially outer side of the coolant space; and via a second coupling part on the radially inner side of the coolant space. In axial view, the first coupling part and the second coupling part overlap the iron core.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] A technique is known in which a coil end cover that covers a coil end portion and an outer cover that covers the outer periphery of a stator core are joined together via a radial snap fit portion. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-226870 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the above-described conventional technology has problems such as an increase in the radial size of the entire rotating electric machine due to the outer cover itself, and an increase in the radial size of the entire rotating electric machine due to the snap-fit ​​portion protruding radially outward.

[0005] Therefore, in one aspect, an object of the present disclosure is to reliably fix a cover member that covers a coil end portion while preventing or minimizing an increase in the radial size of the entire rotating electric machine. [Means for solving the problem]

[0006] According to one aspect, a rotor includes an iron core having a plurality of teeth; a coil wire wound around the iron core in a manner to be inserted into slots formed between the plurality of teeth in the circumferential direction, the coil wire forming a coil end portion on the axially outer side of an axial end face of the iron core; a first cover member that covers the coil end portion from an axially outer side, a radially inner side, and a radially outer side; a second cover member covering an axial end face of the iron core; a refrigerant space between the first cover member and the second cover member, the first cover member and the second cover member are joined to each other via a first joint portion on the radially outer side of the refrigerant space and a second joint portion on the radially inner side of the refrigerant space in a cross-sectional view taken along a plane passing through the central axis of the iron core, At least one of the first joint portion and the second joint portion overlaps the iron core when viewed in the axial direction. [Effects of the Invention]

[0007] According to one aspect, the present disclosure makes it possible to reliably fix a cover member that covers a coil end portion while preventing or minimizing an increase in the radial size of the entire rotating electric machine. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a cross-sectional view schematically showing a cross-sectional structure of a motor according to an embodiment. [Figure 2] FIG. 2 is a cross-sectional view of a portion of a stator core. [Figure 3] FIG. 2 is a cross-sectional view of the stator taken along line AA in FIG. 1. [Figure 4] FIG. 2 is a perspective view of the stator removed from the motor case. [Figure 5A] FIG. 2 is a cross-sectional view of the stator taken along a plane passing through the rotation axis, at a circumferential position where no slots exist. [Figure 5B] FIG. 2 is a cross-sectional view of the stator taken along a plane perpendicular to the rotation axis, the cross-sectional view being taken along a plane passing through the core end face cover. [Figure 6] FIG. 4 is a perspective view of the coil end cover as a single item, as viewed from the axial outside. [Figure 7] FIG. 4 is a perspective view of the coil end cover as a single item, as viewed from the axially inner side. [Figure 8] FIG. 4 is a perspective view of the core end face cover in a separate state as viewed from the outside in the axial direction. [Figure 9] FIG. 4 is a perspective view of the core end face cover in a single state as viewed from the axially inner side. [Figure 10] FIG. 4 is an enlarged perspective view showing a first snap-fit ​​portion of the joining structure between the coil end cover and the core end face cover. [Figure 11] FIG. 4 is an enlarged perspective view of a second snap-fit ​​portion of the joining structure between the coil end cover and the core end face cover. [Figure 12] FIG. 2 is a cross-sectional view of the stator taken along a plane passing through the rotation axis, the cross-sectional view being at a circumferential position passing through the slot. [Figure 13] FIG. 13 is an enlarged view of part B in FIG. [Figure 14] FIG. 13 is a cross-sectional view taken along line CC in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] Each embodiment will be described in detail below with reference to the accompanying drawings. Note that the dimensional ratios in the drawings are merely examples and are not limiting. Furthermore, shapes and the like in the drawings may be partially exaggerated for the sake of explanation. Furthermore, in the drawings, for ease of viewing, reference symbols may be assigned only to some of the parts that exist with the same attribute.

[0010] Fig. 1 is a cross-sectional view that schematically shows the cross-sectional structure of a motor 1 according to an embodiment. Fig. 2 is a cross-sectional view of a portion of a stator core 211. Fig. 3 is a cross-sectional view of a stator 21 taken along line AA in Fig. 1.

[0011] 1 shows the rotating shaft 12 of the motor 1. In the following description, the axial direction refers to the direction in which the rotating shaft (center of rotation) 12 of the motor 1 extends, the axially outer side refers to the side away from the axial center of the stator core 211, and the axially inner side refers to the side toward the axial center of the stator core 211. The radial direction refers to the radial direction centered on the rotating shaft 12, the radially outer side refers to the side away from the rotating shaft 12, and the radially inner side refers to the side toward the rotating shaft 12. The circumferential direction corresponds to the direction of rotation around the rotating shaft 12.

[0012] The motor 1 may be a motor for driving a vehicle, such as that used in a hybrid vehicle or an electric vehicle, but the motor 1 may also be used for any other purpose.

[0013] The motor 1 is housed in and supported by a motor case 10. The motor case 10 may also house a driving element (such as a reduction mechanism) other than the motor 1. The motor case 10 may be formed by combining multiple case members.

[0014] In this embodiment, the motor 1 is an inner rotor type, and the stator 21 is provided so as to surround the outside of the rotor 30 in the radial direction.

[0015] The stator 21 is fixed to the motor case 10. The stator 21 includes a stator core 211, coil wires 22, a foamed insulator 24 (see FIG. 3), a coil end cover 50, and a core end face cover 60.

[0016] Stator core 211 is formed, for example, from laminated steel plates of a circular magnetic material, but may also be formed from a green compact obtained by compressing and solidifying magnetic powder. Stator core 211 may have an inner peripheral portion and an outer peripheral portion (e.g., a back yoke portion) formed as separate pieces. Stator core 211 may also be formed by combining split cores that are divided in the circumferential direction.

[0017] The stator core 211 has fixing portions 2118 that protrude radially outward. The fixing portions 2118 have bolt fastening holes through which bolts BT1 pass. The stator core 211 is fixed to the motor case 10 by the bolts BT1 fastened to the fixing portions 2118.

[0018] As shown in Fig. 2, the stator core 211 has teeth 214 on the radially inner side, spaced at a constant pitch along the circumferential direction. Slots 216 are formed between adjacent teeth 214 in the circumferential direction. The slots 216 are open on both axial sides and also open on the radially inner side. In this embodiment, the teeth 214 have a shape in which the circumferential dimension increases at the radially inner end 2140. In other words, the teeth 214 have a shape in which the radially inner end 2140 expands in the circumferential direction.

[0019] The coil wire 22 may be a conductor wire covered with an insulating coating. Note that in FIG. 3 and other figures, the coil wire 22 is illustrated without the insulating coating for convenience of drawing. The cross section of the coil wire 22 may be any shape, such as rectangular (rectangular wire) or circular (round wire). The coil wire 22 is wound around the stator core 211 to form a stator coil. Note that the coil wire 22 may be wound in any way, such as concentrated winding or distributed winding.

[0020] The coil wire 22 is wound around the stator core 211 while being inserted into the slots 216. Then, a coil end portion 223 is formed axially outward from the axial end face of the stator core 211. The coil end portion 223 is formed by a portion of the coil wire 22 that spans between the slots 216 in the circumferential direction (a portion outside the slots 216). The coil end portion 223 is formed on each axial side of the stator core 211. The coil end portion 223 has an annular shape when viewed in the axial direction.

[0021] In this embodiment, the coil end portions 223 have a configuration in which the axially outer side is tilted radially outward. In this case, it is easier to ensure a radial gap between the coil wires 22 that form the coil end portions 223. This configuration is suitable when the coil wires 22 that form the coil end portions 223 are in the form of so-called segment coils and are joined together by welding. This is because the larger the radial gap between the coil wires 22, the easier it is to ensure space for a welding jig.

[0022] The foamed insulation 24 is formed by foaming foamed insulation paper (slot paper) 240 (described later) arranged in the slot 216. The foamed insulation 24 surrounds the coil wire 22 in the slot 216. The foamed insulation 24 may be provided so as to close the radially inner opening of the slot 216. For example, the foamed insulation 24 may be arranged so as to extend over the entire axial direction of the slot 216, at a position axially inner than a through hole 62 of a core end face cover 60 (described later). In this case, the core end face cover 60 and the foamed insulation 24 can close the radially inner opening of the slot 216.

[0023] The rotor 30 is disposed radially inside the stator 21 .

[0024] The rotor 30 includes a rotor core 32 and a rotor shaft 34 .

[0025] The rotor core 32 is fixed to the radially outer surface of the rotor shaft 34 and rotates integrally with the rotor shaft 34. The rotor core 32 has an axial hole 320 into which the rotor shaft 34 is fitted. The rotor core 32 may be fixed to the rotor shaft 34 by shrink fitting, press fitting, or the like. For example, the rotor core 32 may be connected to the rotor shaft 34 by key connection or spline connection. The rotor shaft 34 is rotatably supported in the motor case 10 via bearings (bearing 14a, etc.). The rotor shaft 34 defines the rotary axis 12 of the motor 1.

[0026] The rotor core 32 is formed of, for example, laminated steel plates of a circular magnetic material. The rotor core 32 may have permanent magnets provided on the inside or on the radially outer surface thereof.

[0027] The coil end cover 50 surrounds the coil end portion 223. That is, the coil end cover 50 covers the axially outer side, the radially inner side, and the radially outer side of the coil end portion 223. The coil end cover 50 may be made of a resin material if low heat dissipation is important, or may be made of a metal material if this is not the case.

[0028] The core end face cover 60 covers the axial end face 2110 of the stator core 211. The core end face cover 60 has through holes 62 at circumferential positions corresponding to the slots 216. The through holes 62 are formed so that the coil wires 22 extending axially outward from the slots 216 can pass through. The core end face cover 60 may be made of a resin material if low heat dissipation is important, or may be made of a metal material if this is not the case.

[0029] The coil end cover 50 and the core end face cover 60 are joined to each other. The coil end cover 50 and the core end face cover 60 form an oil passage 80 (see FIG. 1 ) that is annular when viewed in the axial direction between them and the axial end face 2110 of the stator core 211. Further details of the coil end cover 50 and the core end face cover 60 will be described later, along with details of the joining structure of the coil end cover 50 and the core end face cover 60.

[0030] 1 shows the motor 1 having a specific structure, but the structure of the motor 1 is not limited to such a specific structure. For example, although the rotor shaft 34 is solid in FIG. 1, it may be hollow.

[0031] Next, the characteristic configuration of this embodiment will be described with reference to Figures 1 and 3, as well as Figure 4 onwards. Below, the configuration on one axial side (such as the coil end cover 50 and the core end face cover 60) will be mainly described, but the configuration on the other axial side may be similar.

[0032] FIG. 4 is a perspective view of the stator 21 removed from the motor case 10. FIG. 5A is a cross-sectional view of the stator 21 taken along a plane passing through the rotating shaft 12, at a circumferential position where no slots 216 are present. FIG. 5A shows only one side symmetrically with respect to the rotating shaft 12. FIG. 5B is a cross-sectional view of the stator 21 taken along a plane perpendicular to the rotating shaft 12, passing through the core end face cover 60. FIG. 5B shows only a partial circumferential range. FIGS. 6 and 7 are perspective views of the coil end cover 50 alone, with FIG. 6 being a perspective view from the axial outside and FIG. 7 being a perspective view from the axial inside. FIGS. 8 and 9 are perspective views of the core end face cover 60 alone, with FIG. 8 being a perspective view from the axial outside and FIG. 9 being a perspective view from the axial inside. FIG. 10 is an enlarged perspective view of the first snap-fit ​​portion 73 of the connection structure between the coil end cover 50 and the core end face cover 60. FIG. 11 is an enlarged perspective view of the second snap-fit ​​portion 74 of the joining structure of the coil end cover 50 and the core end face cover 60. As shown in FIG.

[0033] As shown in Figures 6 and 7, the coil end cover 50 has an annular shape when viewed in the axial direction. The coil end cover 50 has an axially outer top surface portion 5030, a radially outer circumferential surface portion 5031, and a radially inner circumferential surface portion 5032 that form a C-shape when viewed in cross section (Figure 1) along a plane passing through the rotating shaft 12. The top surface portion 5030 and the circumferential surface portions 5031 and 5032 of the coil end cover 50 may form substantially the same C-shape at each circumferential position in a circumferential section when viewed in cross section (Figure 1) along a plane passing through the rotating shaft 12. However, the coil end cover 50 may have oil inlets and outlets (not shown) on the circumferential surface portion 5031 or the like in addition to engagement claws 55 and engagement holes 58 (described later) at local circumferential positions or ranges. The coil end cover 50 defines an oil passage 80 by a C-shaped space formed by the top surface portion 5030 and the peripheral surface portions 5031 and 5032.

[0034] The radially outer peripheral surface portion 5031 faces the radially outer side of the coil end portion 223 from the radially outer side over the entire circumference. An axially inner end of the radially outer peripheral surface portion 5031 engages with the core end face cover 60. The radially outer peripheral surface portion 5031 engages with the core end face cover 60 radially outer than the slot 216 (radially outer than the coil end portion 223).

[0035] Specifically, the radially outer peripheral surface portion 5031 is engaged by a radial interference fit with the radially outer standing peripheral surface portion 631 of the core end face cover 60. In the example shown in the figure, the standing peripheral surface portion 631 presses the peripheral surface portion 5031 in the radial direction from the radially inner side toward the radially outer side. Note that the peripheral surface portion 5031 and the standing peripheral surface portion 631 may be engaged in a manner involving fitting of a radially protruding portion and a radially recessed portion.

[0036] The radially inner peripheral surface portion 5032 faces the radially inner side of the coil end portion 223 from the radially inner side over the entire circumference. The axially inner end of the radially inner peripheral surface portion 5032 engages with the core end face cover 60. The radially inner peripheral surface portion 5032 engages with the core end face cover 60 radially inner than the coil wire 22 in the slot 216.

[0037] Specifically, the radially inner circumferential surface portion 5032 is engaged by a radial interference fit with the radially inner standing circumferential surface portion 632 of the core end face cover 60. In the example shown, the standing circumferential surface portion 632 presses the circumferential surface portion 5031 in the radial direction from the radially outer side toward the radially inner side. Note that the circumferential surface portion 5032 and the standing circumferential surface portion 632 may be engaged in a manner involving the fitting of a radially protruding portion and a radially recessed portion.

[0038] In this manner, in the present embodiment, the coil end cover 50 and the core end face cover 60 are joined to each other via an interference-fit joint portion (hereinafter also referred to as a "first interference-fit portion 71") on the radially outer side of the annular oil passage 80, and via an interference-fit joint portion (hereinafter also referred to as a "second interference-fit portion 72") on the radially inner side of the oil passage 80. The first interference-fit portion 71 and the second interference-fit portion 72 are formed over the entire circumferential direction, so that high sealing performance can be ensured over the entire annular oil passage 80.

[0039] In this embodiment, the first interference fit portion 71 and the second interference fit portion 72 are disposed within a range that overlaps with the stator core 211 when viewed in the axial direction. This allows the coil end cover 50 and the core end face cover 60 to be disposed and coupled without increasing the radial size of the entire motor 1.

[0040] Furthermore, in this embodiment, the first interference fit portion 71 overlaps the coil end portion 223 (coil wire 22) in the axial direction. Specifically, in this embodiment, as described above, the coil end portion 223 has a configuration in which the axially outer side leans radially outward, and the first interference fit portion 71 can be disposed by utilizing the dead space formed by such coil end portion 223. Note that in a modified example, instead of or in addition to the first interference fit portion 71, the second interference fit portion 72 may overlap the coil end portion 223 (coil wire 22) in the axial direction. In this case, the second interference fit portion 72 may be located axially outward from the axial position shown in the drawing and may radially face the axially outer end of the coil end portion 223 from the radially inner side.

[0041] The core end face cover 60 has an annular shape and covers the axial end face of the stator core 211. The core end face cover 60 has a base surface 630 that comes into surface contact with the axial end face of the stator core 211.

[0042] The core end face cover 60 has upstanding circumferential surface portions 631, 632 and a flange portion 68 extending axially outward from a base surface 630. Specifically, the core end face cover 60 has the upstanding circumferential surface portion 632 at its radially inner edge, and on its radially outer side, in addition to the upstanding circumferential surface portion 631, has a flange portion 68 at its radially outer edge (outer peripheral edge). The flange portion 68 is located radially outward from the upstanding circumferential surface portion 631. The flange portion 68 cooperates with the upstanding circumferential surface portion 631 to form a recessed portion 69 that is recessed axially inward. An axially inner end portion of the radially outer circumferential surface portion 5031 of the coil end cover 50 described above is inserted into the recessed portion 69. In this case, the axially inner end portion of the radially outer circumferential surface portion 5031 of the coil end cover 50 is radially covered from the radially outer side by the flange portion 68. In this case, even if the circumferential surface portion 5031 attempts to displace radially outward due to the internal pressure of the oil passage 80 or the like, it is stopped from the radially outer side by the flange portion 68. Therefore, even if the interference at the first interference fit portion 71 becomes smaller due to the internal pressure or the like, it is possible to maintain the joined state on the radially outer side between the coil end cover 50 and the core end face cover 60.

[0043] The radial width of the recess 69 formed by the flange 68 and the standing peripheral surface portion 631 may be approximately the same as the thickness of the radially outer peripheral surface portion 5031 of the coil end cover 50.

[0044] Here, the flange portions 68 may be provided around the entire circumference, but are preferably provided in a circumferential range that avoids the fixed portions 2118 of the stator core 211. In this case, the fixed portions 2118 can be moved radially inward by the amount of the flange portions 68, thereby reducing the radial size of the stator 21. Furthermore, even in this case, the flange portions 68 can be arranged over a relatively wide circumferential range, so that the above-described function of the flange portions 68 (the function of suppressing radially outward displacement of the radially outer peripheral surface portions 5031 of the coil end covers 50) can be ensured over a relatively wide circumferential range.

[0045] As described above, the core end face cover 60 has axial through holes 62 at circumferential positions on the base surface 630 corresponding to each slot 216. The through holes 62 are disposed radially between the upright peripheral surface portions 632 and 631. The through holes 62 are provided to allow the coil wires 22 to extend from within the slots 216 to the radially outer side of the stator core 211. As a result, gaps are formed between the inner circumferential walls of the through holes 62 and the coil wires 22. However, in this embodiment, a foamed insulation 24 is disposed in the through holes 62 in the core end face cover 60. Therefore, the foamed insulation 24 can fill the gaps between the inner circumferential walls of the through holes 62 and the coil wires 22. This makes it difficult for oil in the oil passages 80 to enter the slots 216 through the through holes 62, thereby eliminating or reducing the amount of oil in the oil passages 80 leaking into the slots 216. Even if oil leaks into the slots 216, the foam insulation 24 that closes the radially inner openings of the slots 216 substantially prevents the oil from further leaking from the radially inner openings of the slots 216 to between the stator 21 and the rotor 30 in the radial direction. This makes it possible to prevent the occurrence of drag loss due to oil leaking between the stator 21 and the rotor 30 in the radial direction.

[0046] In this embodiment, the coil end cover 50 and the core end face cover 60 are further joined via a first radial snap fit portion 73 and a second radial snap fit portion 74. In this embodiment, the first snap fit portion 73 and the second snap fit portion 74 are provided on the radial outside of the annular oil passage 80, but instead of or in addition to this, the first snap fit portion 73 and / or the second snap fit portion 74 may be provided on the radial inside of the annular oil passage 80.

[0047] The first snap fit portion 73 and the second snap fit portion 74 are provided at different positions in the circumferential direction, and the radial positional relationship between the engagement claws and engagement holes associated with each snap fit is the same.

[0048] Specifically, the first snap-fit ​​portion 73 is a snap-fit ​​portion between the radially outward engaging claws 55 on the coil end cover 50 side and the engaging holes 65 on the core end face cover 60 side. In this case, during assembly, the engaging claws 55 elastically deform radially inward and then enter the engaging holes 65, thereby elastically restoring their original shape and achieving a snap fit. The engaging holes 65 are formed in the peripheral wall portion relating to the flange portion 68 of the core end face cover 60.

[0049] As shown in Fig. 10, the coil end cover 50 may have a portion including the engagement claws 55 surrounded by a notch. That is, notches may be formed on both circumferential sides of the portion including the engagement claws 55. In this case, the portion including the engagement claws 55 can easily elastically deform radially inward. That is, assembly is easier. Furthermore, the core end face cover 60 may have recessed portions 64 (see Fig. 8) formed therein that allow the engagement claws 55 to deform radially inward during assembly.

[0050] The first snap fit portions 73 are preferably provided at a plurality of locations along the circumferential direction. In this embodiment, as an example, as can be seen from Figures 7 and 9, a total of three first snap fit portions 73 are provided at 120 degree intervals.

[0051] The second snap-fit ​​portion 74 is a snap-fit ​​portion between the radially outward engaging claws 67 on the core end face cover 60 side and the engaging holes 58 on the coil end cover 50 side. In this case, during assembly, the engaging claws 67 are first elastically deformed radially inward and then enter the engaging holes 58, whereupon they elastically return to their original shape, achieving a snap-fit.

[0052] 11, the coil end cover 50 may have a portion including the engagement holes 58 surrounded by cutouts. That is, cutouts may be formed on both circumferential sides of the portion including the engagement holes 58. In this case, the portion including the engagement holes 58 can easily elastically deform radially outward. That is, during assembly, the portion including the engagement holes 58 elastically deforms radially outward, and then receives the engagement claws 67, thereby elastically restoring the original shape and achieving a snap fit.

[0053] The second snap-fit ​​portions 74 are preferably provided at a plurality of locations along the circumferential direction. In this embodiment, as an example, they are provided at a total of three locations at 120-degree intervals, as can be seen from Figures 7 and 9. In this case, the second snap-fit ​​portions 74 are provided at circumferential positions different from those of the first snap-fit ​​portions 73.

[0054] 11, the second snap-fit ​​portion 74 may be provided to match the phase of the fixing portion 2118. Since the flange portion 68 is not provided within the circumferential range of the fixing portion 2118, elastic deformation of the coil end cover 50 radially outward (elastic deformation of the portion including the engagement hole 58) becomes easier.

[0055] Thus, according to this embodiment, in addition to the two interference-fit portions (i.e., the first interference-fit portion 71 and the second interference-fit portion 72) on the inside and outside in the radial direction described above, the first snap-fit ​​portion 73 and the second snap-fit ​​portion 74 are provided. This effectively reduces the possibility of the coupling state between the coil end cover 50 and the core end face cover 60 being released (i.e., the possibility of the coil end cover 50 coming off the core end face cover 60). In particular, as described above, the first snap-fit ​​portion 73 and the second snap-fit ​​portion 74 have the same radial positional relationship between the engagement claws and engagement holes associated with each snap fit. That is, in this embodiment, the engagement claws 55, 67 are located on the same radially inner side relative to the engagement holes 65, 58, respectively. This makes it easier to maintain the coupling state between the coil end cover 50 and the core end face cover 60. That is, for example, deformation in the direction in which the first snap-fit ​​portion 73 is released results in deformation in the direction in which the engagement state of the second snap-fit ​​portion 74 is promoted (strengthened), and vice versa. This significantly reduces the possibility of the connection between the coil end cover 50 and the core end face cover 60 being released (i.e., coming off). To maximize this effect, the first snap fit portion 73 and the second snap fit portion 74 may be positioned relatively close to each other in the circumferential direction. In other words, the first snap fit portion 73 and the second snap fit portion 74 may be positioned adjacent to each other in the circumferential direction.

[0056] Furthermore, in this embodiment, the first snap-fit ​​portion 73 and / or the second snap-fit ​​portion 74 may be disposed within a range that overlaps with the stator core 211 when viewed in the axial direction. This allows the coil end cover 50 and the core end face cover 60 to be firmly joined together without increasing the radial size of the entire motor 1.

[0057] Furthermore, in this embodiment, the first snap-fit ​​portion 73 and / or the second snap-fit ​​portion 74 may be arranged within a range that overlaps the coil end portion 223 (coil wire 22) when viewed in the axial direction. Specifically, in this embodiment, as described above, the coil end portion 223 has a configuration in which the axially outer side is tilted outward in the radial direction, and the first snap-fit ​​portion 73 and / or the second snap-fit ​​portion 74 can be arranged by utilizing the dead space formed by such coil end portion 223.

[0058] Next, a manufacturing method of the stator 21 of this embodiment will be outlined with reference to FIGS. 12 to 14, and in connection therewith, the relationship between the core end face cover 60 and the foamed insulation 24 will be described in detail.

[0059] Fig. 12 is a cross-sectional view of stator 21 in an assembled state, taken along a plane passing through rotating shaft 12 (a cross-sectional view of only one side of rotating shaft 12). Fig. 12 is a cross-sectional view at a circumferential position passing through slot 216. Fig. 13 is an enlarged view of portion B in Fig. 12, and Fig. 14 is a cross-sectional view taken along line CC in Fig. 12. In Figs. 12 to 14, foam insulation paper (slot paper) 240 for forming foam insulation 24 is shown in its pre-foaming state.

[0060] In this embodiment, the core end face cover 60 is fixed to the stator core 211 by joining it to the foam insulation 24 which is fixed in the slot 216 of the stator core 211 .

[0061] As described above, the foamed insulation 24 is formed from the foamed insulation paper (slotted paper) 240. The foamed insulation paper 240 contains, for example, a foaming component that foams when heated, as well as a thermosetting component. In this case, the foamed insulation 24 can be bonded to surrounding parts (such as the core end face cover 60) after foaming.

[0062] In the manufacturing process, as shown in FIG. 13 , the foam insulation paper 240 is inserted into the slot 216 of the stator core 211 with its axial end positioned within the through-hole 62 of the core end-face cover 60. At this time, the foam insulation paper 240 preferably remains within the through-hole 62 and does not extend axially outward beyond the core end-face cover 60. That is, the foam insulation paper 240 preferably terminates axially outward beyond the slot 216 of the stator core 211 and within the through-hole 62 of the core end-face cover 60 (at a position overlapping the through-hole 62 when viewed radially). This allows the foam insulation 24 to be formed so that it bonds to a wide area of ​​the inner circumferential wall of the through-hole 62 after foaming, thereby increasing the fixing strength of the core end-face cover 60 by the foam insulation 24. Furthermore, since the foam insulation 24 does not extend axially outward beyond the core end-face cover 60, the surface area of ​​the coil wire 22 that comes into contact with the oil in the oil passage 80 (the surface area that allows efficient heat dissipation) can be maximized.

[0063] In a comparative example in which foam insulation paper 240 is inserted into slot 216 in a manner that it terminates within slot 216 of stator core 211, when foam insulation paper 240 foams, the foaming material is likely to get into the gap between core end face cover 60 and the axial end face of stator core 211. In contrast, according to this embodiment, foam insulation paper 240 is inserted into slot 216 in a manner that it terminates axially outside slot 216 of stator core 211, thereby reducing the possibility of such a problem occurring.

[0064] Here, in this embodiment, the through holes 62 of the core end face cover 60 may have the same shape as the slots 216, but preferably, unlike the slots 216, they do not have an opening on the radially inner side. That is, the through holes 62 preferably have a closed radially inner side. In this case, when the foam insulation paper 240 foams, the foaming material can be prevented from leaking radially inward from the through holes 62. In other words, the gap around the coil wire 22 in the through holes 62 can be reliably filled by the foam insulation paper 240, and there is no need to provide a separate sealing member on the radially inner side of the core end face cover 60 (for example, a sealing member for sealing a radial opening, if such a member has been provided).

[0065] In the manufacturing process, the foam insulation paper 240 is inserted into the slot 216 in a cylindrical shape with overlapping ends. At this time, the foam insulation 24 is inserted so that the overlapping ends are preferably positioned radially outside the slot 216, as shown in Fig. 14. This reduces the possibility that the foam insulation 24 will protrude radially inward beyond the tips of the teeth 214 from the radially inner opening of the slot 216, while efficiently increasing the bonding area of ​​the foam insulation 24 that is bonded to the core end face cover 60, which will be described later.

[0066] Although each embodiment has been described in detail above, it is not limited to the specific embodiment, and various modifications and changes are possible within the scope of the claims. It is also possible to combine all or a plurality of components of the above-described embodiments.

[0067] In addition to the above disclosure, the following is further disclosed.

[0068] [Appendix 1] an iron core having a plurality of teeth; a coil wire wound around the iron core in a manner to be inserted into slots formed between the plurality of teeth in the circumferential direction, the coil wire forming a coil end portion on the axially outer side of an axial end face of the iron core; a first cover member that covers the coil end portion from an axially outer side, a radially inner side, and a radially outer side; a second cover member covering an axial end face of the iron core; a refrigerant space between the first cover member and the second cover member, the first cover member and the second cover member are joined to each other via a first joint portion on the radially outer side of the refrigerant space and a second joint portion on the radially inner side of the refrigerant space in a cross-sectional view taken along a plane passing through the central axis of the iron core, At least one of the first joint portion and the second joint portion is disposed within a range overlapping the iron core when viewed in the axial direction.

[0069] [Appendix 2] 2. The rotating electric machine according to claim 1, wherein the first joint portion or the second joint portion overlaps with the coil end portion when viewed in the axial direction.

[0070] [Appendix 3] the first coupling portion includes a first radial snap-fit ​​portion and a second radial snap-fit ​​portion; the first snap-fit ​​portion is formed by a first engagement claw provided on the first cover and a second engagement hole provided on the second cover member, The second snap-fit ​​portion is formed by a first engagement hole provided in the first cover and a second engagement claw provided in the second cover member. A rotating electric machine as described in Appendix 1 or 2, wherein the first snap fit and the second snap fit portion are provided at different circumferential positions, and the radial positional relationship between the first engagement claw and the second engagement hole is the same as the radial positional relationship between the second engagement claw and the first engagement hole.

[0071] [Appendix 4] The refrigerant space has an annular shape when viewed in the axial direction, the first coupling portion includes a radial interference fit portion; 4. The rotating electric machine according to claim 1, wherein the interference fit portion is provided over the entire circumferential direction.

[0072] [Appendix 5] the second cover member has a recessed portion recessed axially inward at a radially outer end portion, 5. The rotating electric machine according to claim 1, wherein an axially inner end portion on a radially outer side of the first cover member is fitted into the recess.

[0073] [Appendix 6] The recessed portions are arranged over a first circumferential range of the entire circumferential circumference, The rotating electric machine according to Supplementary notes 3 and 5, wherein the first snap-fit ​​portion and the second snap-fit ​​portion are arranged in a second circumferential range different from the first circumferential range.

[0074] [Appendix 7] The rotating electric machine according to Appendix 6, wherein the iron core has a fixing portion for fixing to a case at one or more circumferential positions on the outer periphery, the fixing portion being at a circumferential position within the second circumferential range. [Explanation of symbols]

[0075] 1 motor (rotating electric machine), 211 stator core (iron core), 2118 fixed portion, 214 teeth portion, 216 slot, 22 coil wire, 223 coil end portion, 80 oil passage (refrigerant space), 50 coil end cover (first cover member), 60 core end face cover (second cover member), 69 recess, 71 first interference fit portion (first connecting portion), 72 second interference fit portion (second connecting portion), 73 first snap fit portion (first connecting portion), 74 second snap fit portion (second connecting portion), 55 engaging claw, 58 engaging hole, 65 engaging hole, 67 engaging claw

Claims

1. an iron core having a plurality of teeth; a coil wire wound around the iron core in a manner to be inserted into slots formed between the plurality of teeth in the circumferential direction, the coil wire forming a coil end portion on the axially outer side of an axial end face of the iron core; a first cover member that covers the coil end portion from an axially outer side, a radially inner side, and a radially outer side; a second cover member covering an axial end surface of the iron core; a refrigerant space between the first cover member and the second cover member, the first cover member and the second cover member are coupled to each other via a first coupling portion on a radially outer side of the refrigerant space and a second coupling portion on a radially inner side of the refrigerant space in a cross-sectional view taken along a plane passing through a central axis of the iron core, At least one of the first joint portion and the second joint portion overlaps the iron core when viewed in the axial direction.

2. The rotating electric machine according to claim 1 , wherein the first joint portion or the second joint portion overlaps with the coil end portion when viewed in the axial direction.

3. 2. The rotating electric machine according to claim 1, wherein one of the first connecting portion and the second connecting portion includes a radial snap-fit ​​portion and a radial interference-fit portion, and the other of the first connecting portion and the second connecting portion includes a radial interference-fit portion.

4. The refrigerant space has an annular shape when viewed in the axial direction, the first coupling portion includes a radial interference fit portion; The rotating electric machine according to claim 1 , wherein the interference-fit portion is provided over the entire circumferential direction.

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