Stator

Abstract

The invention relates to a stator. A magnetic circuit is set to be wide. In a stator according to the present invention, a first wire portion of a coil has a first axis portion and a first inclined portion connected to the first axis portion. The first axis portion extends in the axial direction and is disposed between the first tooth portion and the second tooth portion. The first inclined portion is inclined toward the first tooth portion in the circumferential direction with respect to the first axis portion, and protrudes from the first end surfaces of the plurality of tooth portions. When viewed in the radial direction, a point at which a straight line extending along the side surface of the first tooth section intersects with a straight line extending along the first end surface at a position facing the first line section is defined as a first intersection point. When a point at which a straight line extending along the side surface of the second tooth section and a straight line extending along the first end surface intersect at a position facing the first line section is defined as a second intersection point, the shortest distance between the first intersection point and the first tooth section is greater than the shortest distance between the second intersection point and the second tooth section.

Description

Related Application

[0001] This application claims the priority of a Japanese patent application filed with the Japan Patent Office on January 17, 2024, with application number 2024-005513, the entire content of which is incorporated herein by reference. Technical Field

[0002] The technology disclosed in this specification relates to a stator. Background Art

[0003] Japanese Patent Publication No. 2017-077125 discloses a stator of an electric motor. In this stator, wire portions of a coil are arranged between a plurality of tooth portions. Each wire portion has an axis portion extending in the axial direction and an inclined portion inclined in the circumferential direction with respect to the axis portion. The inclined portion projects from the end face of each tooth portion. In this stator, a stepped recess is formed in the shoulder portion (i.e., the boundary portion between the end face and the side face of each tooth portion) of each tooth portion. By providing the recess in each tooth portion, a gap is ensured between each inclined portion and each tooth portion. Therefore, the height of the coil end can be reduced, and the stator can be miniaturized in the axial direction. Summary of the Invention Problems to be Solved by the Invention

[0004] In Japanese Patent Laid-Open No. 2017-077125, recesses are provided in all the shoulder portions of each tooth portion, and the magnetic path of each tooth portion is narrow. In this specification, a technology is proposed that can achieve miniaturization of the stator and can provide a wider magnetic path in each tooth portion. Means for Solving the Problems

[0005] The stator of Structure 1 disclosed in this specification has: a core portion that is annular with respect to a central axis extending in the axial direction; and a coil wound around the core portion. The core portion has a back yoke and a plurality of tooth portions. The back yoke has a cylindrical shape. The plurality of tooth portions project from the inner circumferential surface of the back yoke, extend in the axial direction, and are arranged at intervals in the circumferential direction. The plurality of tooth portions have: a first tooth portion; and a second tooth portion that is arranged at an interval from the first tooth portion in the circumferential direction. The coil has a first wire portion that has a first axis portion and a first inclined portion connected to the first axis portion. The first axis portion extends in the axial direction and is arranged between the first tooth portion and the second tooth portion. The first inclined portion is inclined in the circumferential direction toward the first tooth portion with respect to the first axis portion and projects from an end surface on one side in the axial direction of the plurality of tooth portions, that is, a first end surface. When observing in the radial direction, a point where a straight line extending along the side surface of the first tooth portion at a position opposite to the first wire portion intersects a straight line extending along the first end surface is set as a first intersection point, and a point where a straight line extending along the side surface of the second tooth portion at a position opposite to the first wire portion intersects a straight line extending along the first end surface is set as a second intersection point. At this time, the shortest distance between the first intersection point and the first tooth portion is greater than the shortest distance between the second intersection point and the second tooth portion. Advantages of the Invention

[0006] In this stator, for the first tooth portion located in the direction in which the first inclined portion is inclined, the shortest distance between the first intersection point and the first tooth portion is large. Therefore, while ensuring the distance between the first inclined portion and the first tooth portion, the first inclined portion can be arranged at a position closer to the first tooth portion in the axial direction. Therefore, the height of the coil end can be reduced, and the stator can be miniaturized. In addition, for the second tooth portion located on the side opposite to the direction in which the first inclined portion is inclined, the shortest distance between the second intersection point and the second tooth portion is small. Therefore, a wider magnetic path of the second tooth portion can be ensured. Description of the Drawings

[0007] Figure 1 is a perspective view of the stator of the embodiment.

[0008] Figure 2 is a perspective view of the stator core.

[0009] Figure 3 is a perspective view of the segmented conductor.

[0010] Figure 4 is a side view of the coil end of the stator core (a view when the core 20 is viewed through from the side).

[0011] Figure 5 is a view showing the plurality of segmented conductors connected in the circumferential direction.

[0012] Figure 6 It is an enlarged top view of the tooth portion 24 and the gap 30 when viewed in the axial direction.

[0013] Figure 7 This is a cross-sectional view obtained by cutting the tooth portion 24 along the circumferential direction at the position of the first line portion S1.

[0014] Figure 8 It is a perspective view showing the end portion of the tooth portion 24 on the end surface 20 a side.

[0015] Figure 9 This is an enlarged cross-sectional view of a section obtained by cutting the tooth portion 24 in the circumferential direction at a position including the first line portion S1 and the end surface 20 a , as viewed in the radial direction.

[0016] Figure 10 This is an enlarged cross-sectional view of a section obtained by cutting the tooth portion 24 in the circumferential direction at a position including the second line portion S2 and the end surface 20 a , as viewed in the radial direction.

[0017] Figure 11 This is an enlarged cross-sectional view of a section obtained by cutting the tooth portion 24 in the circumferential direction at a position including the first line portion S1 and the end surface 20 b , as viewed in the radial direction.

[0018] Figure 12 This is an enlarged cross-sectional view of a section obtained by cutting the tooth portion 24 in the circumferential direction at a position including the second line portion S2 and the end surface 20 b , as viewed in the radial direction.

[0019] Figure 13 The tooth portion 24 of the modification example 1 is Figure 9 The corresponding cross-sectional view.

[0020] Figure 14 The tooth portion 24 of the second modification is Figure 9 The corresponding cross-sectional view.

[0021] Figure 15 The tooth portion 24 of the modification example 3 is Figure 6 Corresponding enlarged top view.

[0022] Figure 16 The tooth portion 24 of the modification example 4 is Figure 6 Corresponding enlarged top view. DETAILED DESCRIPTION

[0023] Next, based on the above-mentioned structure 1, an additional structure of the stator disclosed in this specification will be described.

[0024] (Structure 2) According to the stator of structure 1, The coil has a second wire portion, the second wire portion having a second axis portion and a second inclined portion connected to the second axis portion. The second axial portion extends along the axial direction and is disposed between the first tooth portion and the second tooth portion. The first axial portion and the second axial portion are stacked in the radial direction. The second inclined portion is inclined in the circumferential direction toward the second tooth portion with respect to the second axial portion and protrudes from the first end face. When viewed in the radial direction, the intersection point of the straight line extending along the side surface of the first tooth portion and the straight line extending along the first end face at a position opposite to the second line portion is defined as the third intersection point, and the intersection point of the straight line extending along the side surface of the second tooth portion and the straight line extending along the first end face at a position opposite to the second line portion is defined as the fourth intersection point. At this time, the shortest distance between the fourth intersection point and the second tooth portion is greater than the shortest distance between the third intersection point and the first tooth portion.

[0025] (Structure 3) The stator according to Structure 2. Respectively have a plurality of the first line portions and a plurality of the second line portions. Between the first tooth portion and the second tooth portion, the first line portion and the second line portion are alternately stacked in the radial direction.

[0026] (Structure 4) The stator according to any one of Structures 1 to 3. The first inclined portion passes through the region between the first intersection point and the first tooth portion.

[0027] (Structure 5) The stator according to any one of Structures 1 to 4. A stepped recess is provided at a portion of the boundary between the side surface of the first tooth portion and the first end face that is opposite to the first inclined portion.

[0028] (Structure 6) The stator according to any one of Structures 1 to 4. A chamfered portion is provided at a portion of the boundary between the side surface of the first tooth portion and the first end face that is opposite to the first inclined portion.

[0029] (Structure 7) The stator according to Structure 5 or 6. The bent portion between the first axial portion and the first inclined portion is axially disposed within the range of the recess or the chamfered portion.

[0030] (Structure 8) The stator according to any one of Structures 1 to 7. The first linear portion has a third inclined portion that is connected to the first axial portion on the side opposite to the first inclined portion. The third inclined portion is inclined with respect to the first axial portion in the circumferential direction toward the direction approaching the second tooth portion, and protrudes from a second end surface on the side opposite to the first end surface of the plurality of tooth portions. When viewed in the radial direction, a point where a straight line extending along the side surface of the first tooth portion at a position opposite to the first linear portion intersects a straight line extending along the second end surface is defined as a fifth intersection point, and a point where a straight line extending along the side surface of the second tooth portion at a position opposite to the first linear portion intersects a straight line extending along the second end surface is defined as a sixth intersection point. At this time, the shortest distance between the sixth intersection point and the second tooth portion is greater than the shortest distance between the fifth intersection point and the first tooth portion.

[0031] (Structure 9) The stator according to Structure 3. Regarding the shortest distance between the first intersection point and the first tooth portion and the shortest distance between the fourth intersection point and the second tooth portion, the greater the position is in the radial direction and closer to the inner side.

[0032] (Structure 10) The stator according to Structure 3. Regarding the shortest distance between the first intersection point and the first tooth portion and the shortest distance between the fourth intersection point and the second tooth portion, the smaller the position is in the radial direction and closer to the inner side.

[0033] (Structure 11) The stator according to Structure 2 or 3. Between the first tooth portion and the second tooth portion, the two first linear portions and the two second linear portions are stacked in the radial direction.

[0034] According to Structures 2 to 3, it is possible to ensure a wider magnetic path while miniaturizing the stator.

[0035] According to Structure 4, it is possible to further miniaturize the stator.

[0036] According to Structure 7, it is possible to ensure a wider distance between the first linear portion and the core portion.

[0037] According to Structure 8, it is possible to ensure a wider magnetic path while miniaturizing the stator.

[0038] Figure 1The stator 10 of the illustrated embodiment has a substantially cylindrical shape. Hereinafter, the direction parallel to the central axis AX of the stator 10 is referred to as the axial direction. Further, hereinafter, the direction along the circumference centered on the central axis AX is referred to as the circumferential direction. Further, one direction in the circumferential direction is referred to as direction C1, and the other direction in the circumferential direction is referred to as direction C2. Further, hereinafter, the direction along the radius of the circle centered on the central axis AX is referred to as the radial direction. Although not shown, a rotor is disposed inside the central hole of the stator 10. The rotor is disposed concentrically with the stator 10. An electric motor is constituted by the stator 10 and the rotor. The stator 10 has a core portion 20 and a coil 50. The coil 50 is wound around the core portion 20.

[0039] The core portion 20 may be a core portion made of laminated electromagnetic steel sheets or a pressed core portion. As Figure 2 shown, the core portion 20 has a back yoke 22 and a plurality of tooth portions 24. The back yoke 22 has a cylindrical shape.

[0040] The core portion 20 has an end face 20a on one side in the axial direction and an end face 20b on the other side. The end faces 20a and 20b extend along a plane orthogonal to the central axis AX. A plurality of tooth portions 24 are provided on the inner peripheral surface of the back yoke 22. It should be noted that, in Figure 2 the shape of each tooth portion 24 is simply shown. Each tooth portion 24 is a convex portion protruding from the inner peripheral surface of the back yoke 22 toward the central axis AX. Each tooth portion 24 extends relatively long in the axial direction. Each tooth portion 24 extends from the end face 20a to the end face 20b. That is, both end faces in the axial direction of each tooth portion 24 are constituted by the end face 20a and the end face 20b. The plurality of tooth portions 24 are arranged at intervals in the circumferential direction. A groove-like gap 30 is provided between the tooth portions 24. The gap 30 extends in the axial direction from the end face 20a to the end face 20b.

[0041] Figure 3 The segmented conductor 52 constituting the coil 50 is shown. The segmented conductor 52 is a bent rod-shaped metal member. The surface of the segmented conductor 52 is covered with an insulating coating. The coil 50 is constituted by a plurality of segmented conductors 52 connected to each other. The segmented conductor 52 has a U-shaped portion 52a bent in a U shape and two axial portions 52b extending linearly from the U-shaped portion 52a. In Figure 3 the dotted line shows the shape of the segmented conductor 52 before being mounted on the core portion 20. In the segmented conductor 52 before being mounted on the core portion 20, each axial portion 52b extends linearly to the end portion 52c on the side opposite to the U-shaped portion 52a.

[0042] As Figure 4 shown, each axial portion 52b of the segmented conductor 52 is inserted through the corresponding gap 30 from the end face 20a. The two axial portions 52b of one segmented conductor 52 are respectively inserted through different gaps 30. As Figure 5As shown, each segmented conductor 52 is inserted through and into each gap 30 in such a way that the end 52c protrudes from the end face 20b of the core 20. After each segmented conductor 52 is inserted through and into the gap 30, as Figure 3 , 5 shown, the portion protruding from the end face 20b of the core 20 is bent in the circumferential direction. As Figure 5 shown, after each segmented conductor 52 is bent on the end face 20b side, the ends 52c of adjacent segmented conductors 52 are connected to each other by welding or the like. In this way, the coil 50 is formed by the segmented conductors 52 connected to each other. It should be noted that, although not shown, insulating members such as insulating paper are disposed between the segmented conductors 52 and the core 20. In the state where the coil 50 is completed, each axis portion 52b extends in the axial direction within the corresponding gap 30. Hereinafter, the portions of each segmented conductor 52 that are inclined in the circumferential direction with respect to the axis portion 52b will be referred to as inclined portions 52d and 52f. The inclined portion 52d protrudes from the end face 20a. That is, the inclined portion 52d extends in the axial direction from a position within the core 20 to a position outside the end face 20a. The inclined portion 52f protrudes from the end face 20b. That is, the inclined portion 52f extends in the axial direction from a position within the core 20 to a position outside the end face 20b. In addition, hereinafter, the portion where the segmented conductor 52 is bent at the boundary between the axis portion 52b and the inclined portion 52d will be referred to as the bent portion 52e, and the portion where the segmented conductor 52 is bent at the boundary between the axis portion 52b and the inclined portion 52f will be referred to as the bent portion 52g. In addition, the portion of each segmented conductor 52 that linearly extends from one end to the other end in the axial direction (that is, the linear portion including the inclined portion 52d, the axis portion 52b, and the inclined portion 52f) will be referred to as the wire portion S.

[0043] As Figure 6 shown, within each gap 30, two first wire portions S1a and S1b and two second wire portions S2a and S2b are alternately stacked in the radial direction. Within each gap 30, the wire portions S1a, S2a, S1b, and S2b are arranged in order from the inner circumferential side. Within each gap 30, four axis portions 52b are stacked in the radial direction. It should be noted that hereinafter, the first wire portions S1a and S1b may be collectively referred to as the first wire portion S1, and the second wire portions S2a and S2b may be collectively referred to as the second wire portion S2.

[0044] Figure 6 The dashed arrows shown indicate the directions in which the respective inclined portions 52d are inclined with respect to the axis portion 52b within the gap 30 at the end face 20a. As Figure 6 , 7As shown, the inclined portion 52d of the first line portion S1 is inclined in the direction C1, and the inclined portion 52d of the second line portion S2 is inclined in the direction C2. That is, in each slit 30, the first line portions S1 with the inclined portion 52d inclined in the direction C1 and the second line portions S2 with the inclined portion 52d inclined in the direction C2 are alternately arranged in the radial direction.

[0045] like Figure 7 As shown, at the end surface 20b, the inclined portion 52f of the first line portion S1 is inclined in the direction C2, and the inclined portion 52f of the second line portion S2 is inclined in the direction C1. That is, in each gap 30, the first line portion S1 with the inclined portion 52f inclined in the direction C2 and the second line portion S2 with the inclined portion 52f inclined in the direction C1 are alternately arranged in the radial direction.

[0046] like Figure 8 As shown, each tooth portion 24 has side surfaces 24a and 24b. The side surfaces 24a and 24b are planes extending in the axial direction. The side surface located on the direction C1 side relative to the gap 30 is the side surface 24a, and the side surface located on the direction C2 side relative to the gap 30 is the side surface 24b. In addition, the boundary between the side surface of each tooth portion 24 and the end surface (i.e., the end surface of the tooth portion 24 in the axial direction) is referred to as the shoulder portion 25. Figure 8 As shown, the shoulder 25 is a portion of a ridgeline extending in the radial direction. A plurality of recesses 26 are provided on each shoulder 25. More specifically, two recesses 26a are provided on the shoulder 25a between the side surface 24a and the end surface 20a. The recesses 26a are arranged at intervals in the radial direction. In addition, two recesses 26b are provided on the shoulder 25b between the side surface 24b and the end surface 20a. The recesses 26b are arranged at intervals in the radial direction. Each recess 26 is a stepped recess. As shown in FIG. Figure 6 As shown, in each gap 30, the recess 26a and the recess 26b are arranged differently from each other in the radial direction. That is, the radial positions of the recess 26a and the recess 26b located on both sides of each gap 30 are staggered. In more detail, the recess 26a is provided in the area of the shoulder 25a opposite to the first line portion S1 (that is, the area overlapping with the first line portion S1 when viewed in the circumferential direction), and the recess is not provided in the area of the shoulder 25b opposite to the line portion S1. In addition, the recess is not provided in the area of the shoulder 25a opposite to the second line portion S2, and the recess 26b is provided in the area of the shoulder 25b opposite to the second line portion S2. As described above, the inclined portion 52d of the first line portion S1 is inclined in the direction C1, and the inclined portion 52d of the second line portion S2 is inclined in the direction C2 (refer to Figure 6(by the dashed arrow). Therefore, a recess 26a is provided in a region of the shoulder 25a that faces the first line portion S1 and is in a direction in which the inclined portion 52d of the first line portion S1 is inclined with respect to the gap 30. Further, a recess 26b is provided in a region of the shoulder 25b that faces the second line portion S2 and is in a direction in which the inclined portion 52d of the second line portion S2 is inclined with respect to the gap 30.

[0047] Figure 9 FIG. shows a circumferential cross-section of the shoulders 25a and 25b in a range adjacent to the first line portion S1. It should be noted that in Figures 9 - 14 , the tooth portion 24 on the C1 side with respect to the line portion S is shown as the first tooth portion 24-1, and the tooth portion 24 on the C2 side with respect to the line portion S is shown as the second tooth portion 24-2. In other words, the tooth portion 24 disposed on the inclined side of the inclined portion 52d of the first line portion S1 is the first tooth portion 24-1, and the tooth portion 24 disposed on the opposite side thereof is the second tooth portion 24-2. Which tooth portion 24 corresponds to the first tooth portion and the second tooth portion varies depending on the line portion S used as a reference. In Figures 9 - 14 the range shown, the tooth portion 24 on the left side in the drawing is the first tooth portion 24-1, and the tooth portion 24 on the right side in the drawing is the second tooth portion 24-2. In a range adjacent to the first line portion S1, a recess 26a is provided in the shoulder 25a, and no recess is provided in the shoulder 25b. Figure 9 The first intersection point P1 shows a point where a straight line extending along the side surface 24a of the first tooth portion 24-1 intersects a straight line extending along the end surface 20a at a position opposite to the first line portion S1. Further, the second intersection point P2 shows a point where a straight line extending along the side surface 24b of the second tooth portion 24-2 intersects a straight line extending along the end surface 20a at a position opposite to the first line portion S1. Further, the shortest distance L is the shortest distance between the intersection point P and the tooth portion 24 when viewed in the radial direction. The shortest distance L between the first intersection point P1 and the first tooth portion 24-1 is the distance between the first intersection point P1 and the side surface of the recess 26a. Further, since the second intersection point P2 overlaps with the shoulder 25b, the shortest distance L between the second intersection point P2 and the second tooth portion 24-2 is 0. Therefore, in a region opposite to the first line portion S1, the shortest distance L between the first intersection point P1 and the first tooth portion 24-1 is greater than the shortest distance L between the second intersection point P2 and the second tooth portion 24-2. As Figure 9 shown, the bent portion 52e of the first line portion S1 is axially disposed within the range of the recess 26a. That is, the bent portion 52e of the first line portion S1 is disposed below (closer to the end surface 20b side) the end surface 20a and above (closer to the end surface 20a side) the bottom surface of the recess 26a. The inclined portion 52d of the first line portion S1 passes through the recess 26a (i.e., the region between the first intersection point P1 and the first tooth portion 24-1).

[0048] Figure 10 Shows a circumferential cross-section of the shoulders 25a, 25b in the range adjacent to the second line portion S2. In the range adjacent to the second line portion S2, no recess is provided in the shoulder 25a, and a recess 26b is provided in the shoulder 25b. Figure 10 The third intersection point P3 shows the point where a straight line extending along the side surface 24a intersects a straight line extending along the end surface 20a at a position opposite to the second line portion S2. In addition, the fourth intersection point P4 shows the point where a straight line extending along the side surface 24b intersects a straight line extending along the end surface 20a at a position opposite to the second line portion S2. In the region opposite to the second line portion S2, the shortest distance L between the third intersection point P3 and the first tooth portion 24-1 is 0. In addition, in the region opposite to the second line portion S2, the shortest distance L between the fourth intersection point P4 and the second tooth portion 24-2 is the distance between the fourth intersection point P4 and the side surface of the recess 26b. Therefore, in the region opposite to the second line portion S2, the shortest distance L between the fourth intersection point P4 and the second tooth portion 24-2 is greater than the shortest distance L between the third intersection point P3 and the first tooth portion 24-1. The bent portion 52e of the second line portion S2 is axially disposed within the range of the recess 26b. The inclined portion 52d of the second line portion S2 passes through the recess 26b (i.e., the region between the fourth intersection point P4 and the second tooth portion 24-2).

[0049] As Figure 7 shown, on the end surface 20b side, recesses 26c, 26d are also provided in the shoulders 25c, 25d of each tooth portion 24. It should be noted that the shoulder 25c is the boundary portion between the side surface 24a and the end surface 20b, and the shoulder 25d is the boundary portion between the side surface 24b and the end surface 20b.

[0050] Figure 11 Shows a circumferential cross-section of the shoulders 25c, 25d in the range adjacent to the first line portion S1. In the range adjacent to the first line portion S1, no recess is provided in the shoulder 25c, and a recess 26d is provided in the shoulder 25d. Figure 11The fifth intersection point P5 is shown as the point where a straight line extending along the side surface 24a at a position opposite to the first line portion S1 intersects with a straight line extending along the end surface 20b. Additionally, the sixth intersection point P6 is shown as the point where a straight line extending along the side surface 24b at a position opposite to the first line portion S1 intersects with a straight line extending along the end surface 20b. In the region opposite to the first line portion S1, the shortest distance L between the fifth intersection point P5 and the first tooth portion 24-1 is 0. Additionally, in the region opposite to the first line portion S1, the shortest distance L between the sixth intersection point P6 and the second tooth portion 24-2 is the distance between the sixth intersection point P6 and the side surface of the recess 26d. Therefore, in the region opposite to the first line portion S1, the shortest distance L between the sixth intersection point P6 and the second tooth portion 24-2 is greater than the shortest distance L between the fifth intersection point P5 and the first tooth portion 24-1. The bent portion 52g of the first line portion S1 is axially disposed within the range of the recess 26d. The inclined portion 52f of the first line portion S1 passes through the recess 26d (i.e., the region between the sixth intersection point P6 and the second tooth portion 24-2).

[0051] Figure 12 Shows the circumferential cross-section of the shoulders 25c, 25d in the range adjacent to the second line portion S2. In the range adjacent to the second line portion S2, a recess 26c is provided in the shoulder 25c, and no recess is provided in the shoulder 25d. Figure 12 The seventh intersection point P7 is shown as the point where a straight line extending along the side surface 24a at a position opposite to the second line portion S2 intersects with a straight line extending along the end surface 20b. Additionally, the eighth intersection point P8 is shown as the point where a straight line extending along the side surface 24b at a position opposite to the second line portion S2 intersects with a straight line extending along the end surface 20b. In the region opposite to the second line portion S2, the shortest distance L between the seventh intersection point P7 and the first tooth portion 24-1 is the distance between the seventh intersection point P7 and the side surface of the recess 26c. Additionally, in the region opposite to the second line portion S2, the shortest distance L between the eighth intersection point P8 and the second tooth portion 24-2 is 0. Therefore, in the region opposite to the second line portion S2, the shortest distance L between the seventh intersection point P7 and the first tooth portion 24-1 is greater than the shortest distance L between the eighth intersection point P8 and the second tooth portion 24-2. The bent portion 52g of the second line portion S2 is axially disposed within the range of the recess 26c. The inclined portion 52f of the second line portion S2 passes through the recess 26c (i.e., the region between the seventh intersection point P7 and the first tooth portion 24-1).

[0052] As described above, in the stator 10, at the position on the inclined side of the inclined portion of each wire portion S in each slit 30, a recess 26 is provided in the shoulder portion 25. Therefore, a sufficient insulation distance can be ensured between the inclined portion of the wire portion S and the tooth portion 24, and at the same time, the bent portions 52e and 52g of the wire portion S can be arranged near the tooth portion 24. By arranging the bent portions 52e and 52g of the wire portion S near the tooth portion 24, the size of the stator 10 in the axial direction can be reduced. In particular, in the present embodiment, since the inclined portion of the wire portion S passes through the recess 26, the size of the stator 10 in the axial direction can be further reduced.

[0053] In addition, in the stator 10, at the position on the side opposite to the inclined side of the inclined portion of the wire portion S in each slit 30, no recess is provided in the shoulder portion 25. Therefore, a relatively wide magnetic path cross-sectional area can be ensured in each tooth portion 24. Therefore, magnetic saturation in the stator 10 is suppressed. Therefore, high torque performance can be achieved in the electric motor using the stator 10.

[0054] As described above, according to the embodiment, miniaturization of the stator 10 can be achieved, and the magnetic path can be made wider in each tooth portion 24.

[0055] It should be noted that, in the above embodiment, the coil is a segmented coil composed of a plurality of segmented conductors, but the coil is not limited to a segmented coil. The coil can also be a coil formed by winding a wire.

[0056] It should be noted that, in the above embodiment, at the shoulder portion 25 on the side opposite to the inclined side of the inclined portion of the wire portion S, the shortest distance L is 0. However, it can also be as Figure 13 shown, a chamfered portion is provided at the shoulder portion 25 on the side opposite to the inclined side of the inclined portion of the wire portion S. In this case, by making the shortest distance L of the shoulder portion 25 on the inclined side of the inclined portion greater than the shortest distance L of the shoulder portion 25 on the opposite side, miniaturization of the stator and ensuring of the magnetic path can also be achieved.

[0057] In addition, in the above embodiment, a stepped recess 26 is provided in the shoulder portion 25 at the position on the inclined side of the inclined portion of the wire portion S. However, it can also be as Figure 14 shown, a chamfered portion 26x is provided in the shoulder portion 25 at the position on the inclined side of the inclined portion of the wire portion S. By providing the chamfered portion 26x, the shortest distance L can be increased. In this case, it is also possible that each of the bent portions 52e and 52g is arranged in the axial direction within the range of the chamfered portion 26x.

[0058] In addition, in the above embodiment, the shortest distance L of each recess is constant, but the shortest distance L of each recess (for example, the width and depth of the recess 26 in the circumferential direction) can also vary according to the position in the radial direction. For example, there is as Figure 15As shown, the width of each gap 30 becomes wider toward the outer peripheral side. In this case, for the line portion S located more radially inward, it is more difficult to ensure the insulation distance from the tooth portion 2. Therefore, it can also be as Figure 15 shown that the more radially inner the recess 26 is, the larger the shortest distance L (in Figure 15 , the circumferential width of the recess 26). According to this structure, since the shortest distance L of each recess can be set to the minimum, a wider magnetic path can be ensured. It should be noted that in the case where a chamfered portion is provided instead of the recess, it can also be that the more radially inner the chamfered portion is, the larger the shortest distance L is.

[0059] In addition, Figure 16 each dashed line 90 in Figure 16 shows the connection relationship of each line portion S of the coil end. As Figure 16 shown, the more radially outer the line portion S is, the longer the connection distance of the coil end, and thus the larger the inclination angle of the inclined portion. Therefore, it can also be as Figure 16 shown that the more radially inner the recess is, the smaller the shortest distance L (in

[0060] In the above, the embodiments have been described in detail, but these are merely examples and do not limit the claims. The technologies described in the claims include the technologies obtained by various deformations and changes of the above-exemplified specific examples. The technical features described in this specification or the drawings can exhibit technical utility alone or through various combinations, and are not limited to the combinations recited in the claims at the time of application. In addition, the technologies exemplified in this specification or the drawings can achieve multiple purposes simultaneously, and achieving one of the purposes itself has technical utility.

Claims

1. A stator having: A core portion that is annular with respect to a central axis extending in the axial direction; and A coil wound around the core portion, The core portion has: Back yoke, which has a cylindrical shape; And A plurality of tooth portions that project from the inner peripheral surface of the back yoke, extend in the axial direction, and are arranged at intervals in the circumferential direction, The plurality of tooth portions have: A first tooth portion; And A second tooth portion that is arranged at an interval from the first tooth portion in the circumferential direction, The coil has a first wire portion that has a first axis portion and a first inclined portion connected to the first axis portion, The first axis portion extends in the axial direction and is arranged between the first tooth portion and the second tooth portion, The first inclined portion is inclined in the circumferential direction toward the first tooth portion with respect to the first axis portion and projects from an end surface on one side in the axial direction of the plurality of tooth portions, that is, a first end surface, When observing in the radial direction, a point where a straight line extending along the side surface of the first tooth portion at a position opposite to the first wire portion intersects a straight line extending along the first end surface is set as a first intersection point, and a point where a straight line extending along the side surface of the second tooth portion at a position opposite to the first wire portion intersects a straight line extending along the first end surface is set as a second intersection point. At this time, the shortest distance between the first intersection point and the first tooth portion is greater than the shortest distance between the second intersection point and the second tooth portion.

2. The stator according to claim 1, wherein The coil has a second wire portion that has a second axis portion and a second inclined portion connected to the second axis portion, The second axis portion extends in the axial direction and is arranged between the first tooth portion and the second tooth portion, The first axis portion and the second axis portion are stacked in the radial direction, The second inclined portion is inclined in the circumferential direction toward the second tooth portion with respect to the second axis portion and projects from the first end surface, When observing in the radial direction, a point where a straight line extending along the side surface of the first tooth portion at a position opposite to the second wire portion intersects a straight line extending along the first end surface is set as a third intersection point, and a point where a straight line extending along the side surface of the second tooth portion at a position opposite to the second wire portion intersects a straight line extending along the first end surface is set as a fourth intersection point. At this time, the shortest distance between the fourth intersection point and the second tooth portion is greater than the shortest distance between the third intersection point and the first tooth portion.

3. The stator according to claim 2, wherein There are a plurality of the first wire portions and a plurality of the second wire portions respectively, Between the first tooth portion and the second tooth portion, the first wire portion and the second wire portion are alternately stacked in the radial direction.

4. The stator according to any one of claims 1 to 3, wherein The first inclined portion passes through the region between the first intersection point and the first tooth portion.

5. The stator according to claim 1, wherein A stepped recess is provided at a portion of the boundary between the side surface and the first end surface of the first tooth portion that is opposite to the first inclined portion.

6. The stator according to claim 1, wherein A chamfered portion is provided at a portion of the boundary between the side surface and the first end surface of the first tooth portion, which is opposite to the first inclined portion.

7. The stator according to claim 5 or 6, wherein a bent portion between the first axis portion and the first inclined portion is axially disposed within the range of the concave portion or the chamfered portion.

8. The stator according to any one of claims 1 to 3, wherein the first line portion has a third inclined portion connected to the first axis portion on the opposite side of the first inclined portion, the third inclined portion is inclined in the circumferential direction toward the second tooth portion with respect to the first axis portion and protrudes from a second end surface of the plurality of tooth portions on the side opposite to the first end surface, when viewed in the radial direction, a point where a straight line extending along the side surface of the first tooth portion at a position opposite to the first line portion intersects a straight line extending along the second end surface is defined as a fifth intersection point, and a point where a straight line extending along the side surface of the second tooth portion at a position opposite to the first line portion intersects a straight line extending along the second end surface is defined as a sixth intersection point. At this time, the shortest distance between the sixth intersection point and the second tooth portion is greater than the shortest distance between the fifth intersection point and the first tooth portion.

9. The stator according to claim 3, wherein with respect to the shortest distance between the first intersection point and the first tooth portion and the shortest distance between the fourth intersection point and the second tooth portion, the portion closer to the inner side in the radial direction is larger.

10. The stator according to claim 3, wherein with respect to the shortest distance between the first intersection point and the first tooth portion and the shortest distance between the fourth intersection point and the second tooth portion, the portion closer to the inner side in the radial direction is smaller.

11. The stator according to claim 2 or 3, wherein between the first tooth portion and the second tooth portion, the two first line portions and the two second line portions are stacked in the radial direction.

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