Stator of rotary electric machine

Abstract

To easily perform work of binding and fixing a lead wire to an insulator while avoiding unstable binding and fixing of the lead wire to the insulator.SOLUTION: Since the lead wire 35 is locked in the lead groove 70 by interference fit, it is avoided that the binding and fixing of the lead wire 35 to the insulator 50 becomes unstable. Furthermore, since the lead wire 35 is loosely fitted in the return groove 80, the lead wire 35, which is drawn from the lead groove 70 toward the 51b of the outer circumferential surface of the insulator base 51, can be easily drawn back toward the inner circumferential surface of the insulator base 51 through the return groove 80. Therefore, the work of binding and fixing the lead wire 35 to the insulator 50 is easily performed.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a stator for a rotating electrical machine. [Background technology]

[0002] For example, as disclosed in Patent Document 1, a stator for a rotating electric machine includes a stator core, a coil, and an insulator. The stator core has a cylindrical yoke and a plurality of teeth. The plurality of teeth extend from the circumferential surface of the yoke in the radial direction of the yoke. The coil is formed by winding a wire around each tooth. The coil includes coil ends. The coil ends protrude from a core end face, which is the end face of the stator core located in the axial direction of the yoke. The insulator is arranged opposite the core end face. The insulator provides insulation between the coil ends and the core end face. The insulator has a cylindrical insulator base portion arranged in a position overlapping with the yoke in the axial direction. The insulator base portion has a first circumferential surface located on the coil end side and a second circumferential surface located opposite the coil ends.

[0003] The coil has a winding portion formed by winding the wire around the teeth in a concentrated winding manner. A lead wire on the winding end side, which is part of the wire, is drawn out from the winding portion. Here, the winding start side of the winding portion is fixed as the wire is wound around the teeth. Therefore, the winding start side of the winding portion is prevented from loosening. On the other hand, in order to prevent the winding end side of the winding portion from loosening, it is necessary to fix the lead wire on the winding end side.

[0004] Therefore, the insulator base may have a lead-out groove and a return groove. The lead-out groove opens to the insulator end, which is the end of the insulator base opposite the stator core. A first end of the lead-out groove opens to the first peripheral surface of the insulator base, and a second end of the lead-out groove opens to the second peripheral surface of the insulator base. The lead-out groove leads the lead wire from the first peripheral surface side to the second peripheral surface side of the insulator base. The return groove opens to the insulator end, and has a first end opening to the first peripheral surface of the insulator base, and a second end opening to the second peripheral surface of the insulator base. The return groove is located adjacent to the lead-out groove in the circumferential direction of the insulator base. The return groove leads the lead wire, which has been led out of the lead-out groove, from the second peripheral surface side of the insulator base to the first peripheral surface side.

[0005] In this way, the lead wire passes through the lead-out groove and is drawn out to the second peripheral surface side of the insulator base, and then passes through the return groove and is drawn back to the first peripheral surface side of the insulator base, thereby becoming entangled and fixed to the insulator. As a result, the lead wire is fixed to the insulator, and the end-winding portion of the winding is prevented from loosening. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-259318 Summary of the Invention [Problem to be solved by the invention]

[0007] However, if the lead wire is not tightly secured by at least one of the lead groove and the return groove, the lead wire becomes unstable when bound to the insulator. As a result, the end-winding portion of the winding may become loose. On the other hand, if the return groove secures the lead wire with an interference fit, the lead wire may be pulled from the coil end while avoiding interference with other lead wires at the coil end when the lead wire is pulled from the lead groove to the second circumferential surface of the insulator base and then returned to the first circumferential surface of the insulator base via the return groove. In this case, it may be difficult to avoid interference with other lead wires. This makes the task of binding and securing the lead wire to the insulator complicated. [Means for solving the problem]

[0008] A stator for a rotating electric machine that solves the above-described problems includes a stator core having a cylindrical yoke and a plurality of teeth extending from a peripheral surface of the yoke in a radial direction of the yoke, a coil formed by winding a wire around each of the teeth and including coil ends protruding from a core end face, which is an end face of the stator core located in the axial direction of the yoke, and an insulator disposed opposite the core end face and providing insulation between the coil ends and the core end face, wherein the coil has a winding portion formed by winding the wire around the teeth in a concentrated winding, and a lead wire on the winding end side, which is a part of the winding, is drawn out from the winding portion, and the insulator has a cylindrical insulator base portion disposed in a position overlapping the yoke in the axial direction, and the insulator base portion is configured to have a cylindrical shape. a first peripheral surface located on the coil end side of the insulator base, a second peripheral surface located on the opposite side from the coil end, a lead-out groove that opens at an insulator end that is an end of the insulator base opposite the stator core, with a first end opening at the first peripheral surface and a second end opening at the second peripheral surface, and leads the lead wire from the first peripheral surface side to the second peripheral surface side; and a return groove that opens at the insulator end, with a first end opening at the first peripheral surface and a second end opening at the second peripheral surface, and is positioned adjacent to the lead-out groove in the circumferential direction of the insulator base, and leads the lead wire drawn out from the lead-out groove from the second peripheral surface side to the first peripheral surface side, wherein the lead-out groove engages the lead wire with an interference fit, and the return groove engages the lead wire with a clearance fit.

[0009] According to this, because the lead-out grooves retain the lead wires with an interference fit, unstable bundling of the lead wires to the insulator is avoided. Furthermore, because the return grooves retain the lead wires with a clearance fit, the lead wires, which have been drawn from the lead-out grooves toward the second peripheral surface of the insulator base, can be easily pulled back to the first peripheral surface of the insulator base via the return grooves. Therefore, when pulling the lead wires back toward the first peripheral surface of the insulator base via the return grooves, interference with other lead wires at the coil ends can be easily avoided when pulling the lead wires from the coil ends. This facilitates the task of bundling the lead wires to the insulator. As described above, unstable bundling of the lead wires to the insulator is avoided while the task of bundling the lead wires to the insulator is easily performed.

[0010] In the stator of the above-mentioned rotating electric machine, the return groove has a pair of return groove forming surfaces located on both sides of the lead wire, the pair of return groove forming surfaces extending parallel to each other in the axial direction from the end of the insulator, and the width between the pair of return groove forming surfaces is preferably larger than the outer diameter of the lead wire in its original shape.

[0011] According to this, the width between the pair of return groove forming surfaces is larger than the outer diameter of the lead wire in its original shape, so the return groove locks the lead wire with a clearance fit. In this way, the pair of return groove forming surfaces extend parallel to each other in the axial direction of the yoke from the end of the insulator, and the width between the pair of return groove forming surfaces is larger than the outer diameter of the lead wire in its original shape. This configuration is suitable for the return groove to lock the lead wire with a clearance fit.

[0012] In the stator of the above-mentioned rotating electric machine, the return groove has a pair of return groove forming surfaces located on both sides of the lead-out wire, and of the pair of return groove forming surfaces, the return groove forming surface located farther from the lead-out groove has an inclined shape that gradually moves away from the lead-out groove as it approaches the end of the insulator.

[0013] According to this, of the pair of return groove forming surfaces, the return groove forming surface located farther from the pull-out groove is inclined so as to gradually move away from the pull-out groove as it approaches the end of the insulator. Therefore, when the pull-out wire is pulled out from the pull-out groove to the second peripheral surface side of the insulator base and returned to the first peripheral surface side of the insulator base via the return groove, the pull-out wire can be easily passed inside the return groove. This makes it even easier to bind and fix the pull-out wire to the insulator.

[0014] In the stator of the above-mentioned rotating electric machine, the return groove has a pair of return groove forming surfaces located on both sides of the lead wire, and when the return groove is viewed from the axial direction, the pair of return groove forming surfaces are inclined so as to gradually move away from the lead groove as they move from the second circumferential surface toward the first circumferential surface, and the width between the pair of return groove forming surfaces is preferably larger than the outer diameter of the lead wire in its original shape.

[0015] According to this configuration, the width between the pair of return groove-forming surfaces is larger than the outer diameter of the lead wire in its original shape, so the return groove engages the lead wire with a clearance fit. When viewed from the axial direction of the yoke, the pair of return groove-forming surfaces are inclined, gradually moving away from the lead groove as they extend from the second peripheral surface of the insulator base toward the first peripheral surface. Consider, for example, a case in which the pair of return groove-forming surfaces extend from the second peripheral surface of the insulator base toward the first peripheral surface, each maintaining the same distance from the lead groove. Compared to this case, it is easier to return the lead wire, which has been drawn from the lead groove toward the second peripheral surface of the insulator base, to the first peripheral surface of the insulator base via the return groove. This further facilitates the task of tying and securing the lead wire to the insulator.

[0016] In the stator of the above-mentioned rotating electric machine, the lead groove has a pair of lead groove forming surfaces located on both sides of the lead wire, the pair of lead groove forming surfaces extending parallel to each other in the axial direction from the end of the insulator, and the width between the pair of lead groove forming surfaces is preferably smaller than the outer diameter of the lead wire in its original shape.

[0017] According to this, the width between the pair of lead groove forming surfaces is smaller than the outer diameter of the lead wire in its original shape, so the lead groove locks the lead wire with an interference fit. In this way, the pair of lead groove forming surfaces extend parallel to each other in the axial direction of the yoke from the end of the insulator, and the width between the pair of lead groove forming surfaces is smaller than the outer diameter of the lead wire in its original shape. This configuration is suitable for the lead groove to lock the lead wire with an interference fit.

[0018] A stator for a rotating electric machine that solves the above-described problems includes a stator core having a cylindrical yoke and a plurality of teeth extending from a peripheral surface of the yoke in a radial direction of the yoke, a coil formed by winding a wire around each of the teeth and including coil ends protruding from a core end face, which is an end face of the stator core located in the axial direction of the yoke, and an insulator disposed opposite to the core end face and providing insulation between the coil ends and the core end face, wherein the coil has a winding portion formed by winding the wire around the teeth in a concentrated winding manner, and a lead wire on a winding end side, which is a part of the winding, is drawn out from the winding portion, and the insulator has a cylindrical insulator base portion disposed at a position overlapping the yoke in the axial direction, and the insulator base has a first peripheral surface located on the coil end side, a second peripheral surface located opposite the coil ends, and a winding end portion of the insulator base. a lead-out groove that opens at an insulator end opposite the stator core, with a first end opening at the first circumferential surface and a second end opening at the second circumferential surface, and that leads the lead wire from the first circumferential surface side to the second circumferential surface side; and a return groove that opens at the insulator end, with a first end opening at the first circumferential surface and a second end opening at the second circumferential surface, and that is disposed adjacent to the lead-out groove in a circumferential direction of the insulator base and that leads the lead wire drawn out from the lead-out groove back from the second circumferential surface side to the first circumferential surface side, wherein the return groove has a pair of return-groove-forming surfaces located on both sides of the lead wire, and when viewed from the axial direction, the pair of return-groove-forming surfaces are inclined so as to gradually move away from the lead groove as they move from the second circumferential surface toward the first circumferential surface, and the width between the pair of return-groove-forming surfaces is smaller than the outer diameter of the lead wire in its original shape.

[0019] According to this, the width between the pair of return groove-forming surfaces is smaller than the outer diameter of the lead wire in its original shape, so the return groove engages the lead wire with an interference fit. This prevents the lead wire from being unstablely entangled with the insulator. Furthermore, when viewed from the axial direction of the yoke, the pair of return groove-forming surfaces are inclined, gradually moving away from the lead groove as they extend from the second peripheral surface of the insulator base toward the first peripheral surface. Consider, for example, a case in which the pair of return groove-forming surfaces extend from the second peripheral surface of the insulator base toward the first peripheral surface, each maintaining the same distance from the lead groove. Compared to this case, it is easier to pull the lead wire, which has been pulled from the lead groove toward the second peripheral surface of the insulator base, back toward the first peripheral surface of the insulator base via the return groove. Therefore, when the lead wire is pulled back toward the first peripheral surface of the insulator base through the return groove, interference with other lead wires at the coil end can be avoided when the lead wire is pulled from the coil end side. Therefore, the work of tying and fixing the lead wire to the insulator can be easily performed. As described above, the work of tying and fixing the lead wire to the insulator can be easily performed while avoiding instability in the tying and fixing of the lead wire to the insulator.

[0020] In the stator of the above-mentioned rotating electric machine, the lead-out groove has a pair of lead-out groove forming surfaces located on both sides of the lead-out wire, and the width between the pair of lead-out groove forming surfaces is preferably larger than the outer diameter of the lead-out wire in its original shape.

[0021] According to this, the width between the pair of lead-groove-forming surfaces is larger than the outer diameter of the lead wire in its original shape, so the lead grooves retain the lead wire with a clearance fit. Here, for example, if the insulator thermally expands, even if the return grooves retain the lead wire with an interference fit, the lead grooves retain the lead wire with a clearance fit, so that the stress acting on the lead wire from the insulator can be alleviated. This improves the durability of the lead wire and therefore the reliability of the stator of a rotating electric machine.

[0022] In the stator of the above-mentioned rotating electric machine, the insulator base has a protrusion protruding from a portion between the pull-out groove and the return groove on the second circumferential surface, and the lead wire pulled out from the pull-out groove is engaged with a portion of the protrusion opposite the insulator end.

[0023] This allows the lead wire pulled out from the lead groove to the second peripheral surface side of the insulator base to be engaged at the portion of the protrusion opposite the insulator end, thereby further stabilizing the attachment of the lead wire to the insulator. [Effects of the Invention]

[0024] According to the present invention, the work of tying and fixing the lead wire to the insulator can be easily performed while avoiding unstable tying and fixing of the lead wire to the insulator. [Brief explanation of the drawings]

[0025] [Figure 1] FIG. 1 is a cross-sectional view showing a rotating electric machine according to a first embodiment. [Figure 2] FIG. 2 is an exploded perspective view showing the stator core and two insulators. [Figure 3] FIG. 3 is a perspective view of the stator. [Figure 4] FIG. 4 is a perspective view of the stator. [Figure 5] FIG. 5 is an enlarged side view of a portion of the stator. [Figure 6] FIG. 6 is an enlarged cross-sectional view of a portion of the stator. [Figure 7] FIG. 7 is a diagram for explaining the operation of tying and fixing the lead wire to the insulator. [Figure 8] FIG. 8 is a diagram for explaining the operation of tying and fixing the lead wire to the insulator. [Figure 9] FIG. 9 is a diagram for explaining the operation of tying and fixing the lead wire to the insulator. [Figure 10] FIG. 10 is a diagram for explaining the operation of tying and fixing the lead wire to the insulator. [Figure 11] FIG. 11 is an enlarged perspective view of a portion of the stator according to the second embodiment. [Figure 12] FIG. 12 is an enlarged front view of a portion of the stator according to the second embodiment. [Figure 13] FIG. 13 is an enlarged side view showing a part of the stator in the modified example. [Figure 14] FIG. 14 is an enlarged front view of a portion of the stator in the modified example. DETAILED DESCRIPTION OF THE INVENTION

[0026] [First embodiment] A first embodiment of a stator for a rotating electrical machine will be described below with reference to FIGS.

[0027] <Basic configuration of a rotating electric machine> As shown in FIG. 1 , a rotating electric machine 10 includes a stator 11 and a rotor 12. The stator 11 is cylindrical. The rotor 12 is disposed inside the stator 11. The rotor 12 includes a cylindrical rotor core 13 and a plurality of permanent magnets (not shown) embedded in the rotor core 13. The rotor core 13 is fixed to a rotating shaft 14. The rotor core 13 is configured to be rotatable integrally with the rotating shaft 14.

[0028] As shown in FIGS. 1 and 2 , the stator 11 includes a stator core 23. The stator core 23 includes a yoke 24 and a plurality of teeth 25. The yoke 24 is cylindrical. The plurality of teeth 25 extend radially from an inner circumferential surface 24a, which is the circumferential surface of the yoke 24. The plurality of teeth 25 are arranged at intervals in the circumferential direction of the yoke 24. The plurality of teeth 25 are arranged at equal intervals in the circumferential direction of the yoke 24. The circumferential direction of the yoke 24 is also the circumferential direction of the stator core 23. Each tooth 25 extends from the inner circumferential surface 24a of the yoke 24 toward the axis of the stator core 23. In this embodiment, the stator core 23 has 12 teeth 25. The number of teeth 25 is not particularly limited, but is a multiple of three.

[0029] As shown in Fig. 2, both end faces of the yoke 24 located in the axial direction are flat. Both end faces of each tooth 25 located in the axial direction of the yoke 24 are flat. The axial length of the yoke 24 is the same as the axial length of each tooth 25. The end face of the yoke 24 located on one side in the axial direction is located on the same plane as the end face of each tooth 25 located on one side in the axial direction of the yoke 24. The end face of the yoke 24 located on the other side in the axial direction is located on the same plane as the end face of each tooth 25 located on the other side in the axial direction of the yoke 24.

[0030] The end face located on one side of the axial direction of the yoke 24 and the end face of each tooth 25 located on one side of the axial direction of the yoke 24 form a first core end face 23a, which is an end face located on one side of the axial direction of the yoke 24 of the stator core 23. The end face located on the other side of the axial direction of the yoke 24 and the end face of each tooth 25 located on the other side of the axial direction of the yoke 24 form a second core end face 23b, which is an end face located on the other side of the axial direction of the yoke 24 of the stator core 23. The first core end face 23a and the second core end face 23b are core end faces, which are end faces located on the axial direction of the yoke 24 of the stator core 23.

[0031] 1 and 2, each tooth 25 has a tooth extension portion 26 and a tooth flange portion 27. The tooth extension portion 26 is a thin plate extending from the inner circumferential surface 24a of the yoke 24. The tooth extension portion 26 extends from the first core end face 23a to the second core end face 23b of the stator core 23. The tooth flange portions 27 protrude from the ends of the tooth extension portions 26 opposite the yoke 24 to both sides in the circumferential direction of the yoke 24.

[0032] As shown in FIG. 2 , the stator 11 includes two insulators 50. Each insulator 50 is cylindrical. Each insulator 50 is made of, for example, a resin material. Each insulator 50 has an insulator base 51 and a plurality of insulator teeth 52. The insulator base 51 is cylindrical. Each insulator 50 is disposed relative to the stator core 23 with the axis of each insulator base 51 coinciding with the axis of the yoke 24. The insulator base 51 is disposed at a position overlapping the yoke 24 in the axial direction of the yoke 24. The circumferential direction of the insulator base 51 coincides with the circumferential direction of the yoke 24. The radial direction of the insulator base 51 coincides with the radial direction of the yoke 24.

[0033] One of the two insulators 50 is disposed opposite the first core end face 23a of the stator core 23 while in contact with the first core end face 23a. The other of the two insulators 50 is disposed opposite the second core end face 23b of the stator core 23 while in contact with the second core end face 23b. The outer diameter of the insulator base 51 is smaller than the outer diameter of the yoke 24. The inner diameter of the insulator base 51 is the same as the inner diameter of the yoke 24.

[0034] Each insulator tooth 52 extends from the inner circumferential surface 51a of the insulator base 51 in the radial direction of the insulator base 51. The multiple insulator teeth 52 are arranged at intervals in the circumferential direction of the insulator base 51. The multiple insulator teeth 52 are arranged at equal intervals in the circumferential direction of the insulator base 51. Each insulator tooth 52 extends from the inner circumferential surface 51a of the insulator base 51 toward the axis of the insulator base 51. In this embodiment, the insulator 50 has 12 insulator teeth 52. The number of insulator teeth 52 is the same as the number of teeth 25 of the stator core 23.

[0035] Each insulator tooth 52 has an insulator extension 53 and an insulator flange 54. The insulator extension 53 is columnar and extends from the inner circumferential surface 51a of the insulator base 51. The circumferential width of each insulator extension 53 of the insulator base 51 is the same as the circumferential width of each tooth extension 26 of the yoke 24. Each insulator extension 53 is in contact with each tooth 25. The insulator flange 54 protrudes along the insulator base 51 from the end of the insulator extension 53 opposite the insulator base 51.

[0036] A plurality of crossover wire accommodating grooves 61 are formed in the outer peripheral surface 51b of the insulator base 51 of one of the two insulators 50. The plurality of crossover wire accommodating grooves 61 are arranged side by side in the axial direction of the insulator base 51. Each crossover wire accommodating groove 61 extends in the circumferential direction of the yoke 24. Each crossover wire accommodating groove 61 extends around the entire outer peripheral surface 51b of the insulator base 51. Each crossover wire accommodating groove 61 does not penetrate the insulator base 51.

[0037] A plurality of through grooves 62 are formed in the insulator base 51 of one of the two insulators 50. Each through groove 62 penetrates the insulator base 51 in the radial direction. The total number of through grooves 62 matches the number of teeth 25. Each through groove 62 extends in the axial direction of the insulator base 51 from an insulator end 51e, which is the end of the insulator base 51 opposite the stator core 23.

[0038] As shown in Fig. 1, the stator 11 includes three-phase coils 28. The coils 28 each have a plurality of winding portions 30. Each winding portion 30 is formed by winding the wire 31 in a concentrated winding manner so as to collectively surround each tooth extension portion 26 and each insulator extension portion 53 of each insulator 50. Thus, each winding portion 30 is formed by winding the wire 31 around the tooth 25 in a concentrated winding manner.

[0039] The winding of the winding 31 of the coil 28 of each phase onto the tooth extensions 26 and the insulator extensions 53 of the insulators 50 is performed automatically by, for example, winding equipment equipped with a winding nozzle.

[0040] 3, a part of the winding portion 30 is a first coil end 281 that protrudes from the first core end face 23a. Therefore, the first coil end 281 is a coil end that protrudes from the first core end face 23a. The first coil end 281 is a part of the coil 28.

[0041] 4, a part of the winding portion 30 is a second coil end 282 that protrudes from the second core end face 23b. Therefore, the second coil end 282 is a coil end that protrudes from the second core end face 23b. The second coil end 282 is a part of the coil 28.

[0042] In this way, coil 28 includes first coil end 281 protruding from first core end face 23a. Coil 28 also includes second coil end 282 protruding from second core end face 23b. Therefore, coil 28 includes coil ends protruding from the core end faces. In this way, coil 28 is formed by winding wire 31 around each tooth 25.

[0043] 3, of the two insulators 50, the insulator 50 arranged opposite the first core end face 23a of the stator core 23 provides insulation between the first coil end 281 and the first core end face 23a. Therefore, one of the two insulators 50 provides insulation between the coil 28 and the first core end face 23a. The inner circumferential surface 51a of the insulator base 51 of one of the two insulators 50 is a first circumferential surface located on the first coil end 281 side. The outer circumferential surface 51b of the insulator base 51 of one of the two insulators 50 is a second circumferential surface located on the opposite side from the first coil end 281.

[0044] As shown in FIG. 4 , of the two insulators 50, the insulator 50 arranged opposite the second core end face 23b of the stator core 23 provides insulation between the second coil end 282 and the second core end face 23b. Therefore, the other of the two insulators 50 provides insulation between the coil 28 and the second core end face 23b. The inner circumferential surface 51a of the insulator base 51 of the other of the two insulators 50 is a first circumferential surface located on the second coil end 282 side. The outer circumferential surface 51b of the insulator base 51 of the other of the two insulators 50 is a second circumferential surface located on the opposite side from the second coil end 282. In this way, the insulator base 51 has a first circumferential surface located on the coil end side and a second circumferential surface located on the opposite side from the coil end.

[0045] As shown in Fig. 3, a crossover wire 32, which is part of the winding 31, is drawn out from the winding portion 30 of the coil 28 of each phase. The crossover wire 32 of the coil 28 of each phase is drawn out from the first coil end 281 of the coil 28 of each phase. The crossover wire 32 of the coil 28 of each phase connects the winding portions 30 forming the coils 28 of each phase in series. Each crossover wire 32 is housed in each crossover wire housing groove 61 via each through groove 62 and is guided in the circumferential direction of the yoke 24.

[0046] As shown in Fig. 4, a lead wire 34, which is part of the winding 31, extends from the winding portion 30 of the coil 28 of each phase at the winding start side. The lead wire 34 of the coil 28 of each phase extends from the second coil end 282 of the coil 28 of each phase. The lead wire 34 of the coil 28 of each phase is electrically connected to a connection terminal (not shown) housed in the cluster block 40. Power is supplied to the lead wire 34 of the coil 28 of each phase from an external power source via the connection terminal.

[0047] Electric power from an external power source is input to the lead wires 34 of the coils 28 of each phase. By inputting electric power to the coils 28 of each phase in this manner, the rotor 12 and the rotating shaft 14 rotate integrally.

[0048] A lead wire 35, which is part of the winding 31, is drawn out from the winding portion 30 of the coil 28 of each phase on the winding end side. The lead wire 35 of the coil 28 of each phase is drawn out from the second coil end 282 of the coil 28 of each phase. The lead wires 35 of the coils 28 of each phase are electrically connected to each other to form a neutral point.

[0049] <Drawer groove> The other insulator base 51 of the two insulators 50 has a plurality of lead-out grooves 70. The lead-out grooves 70 open to an insulator end 51e, which is the end of the insulator base 51 opposite the stator core 23. The lead-out grooves 70 penetrate the insulator base 51 in the radial direction of the yoke 24. A first end of each lead-out groove 70 opens to an inner circumferential surface 51a of the insulator base 51, and a second end opens to an outer circumferential surface 51b of the insulator base 51. The lead-out grooves 70 lead the lead wires 35 from the inner circumferential surface 51a of the insulator base 51 to the outer circumferential surface 51b of the insulator base 51. In this way, the lead-out grooves 70 lead the lead wires 35 from a position radially inward of the insulator base 51 to a position radially outward of the yoke 24.

[0050] As shown in FIG. 5 , the lead groove 70 has a pair of lead groove forming surfaces 71 and a connecting surface 72. When the lead groove 70 is viewed from the radial direction of the yoke 24, the pair of lead groove forming surfaces 71 extend parallel to each other in the axial direction of the yoke 24 from the insulator end 51e. The pair of lead groove forming surfaces 71 are located on both sides in the circumferential direction of the yoke 24, with the lead wire 35 sandwiched therebetween. The connecting surface 72 connects the ends of the pair of lead groove forming surfaces 71 on the opposite side from the insulator end 51e. When the lead groove 70 is viewed from the radial direction of the yoke 24, the connecting surface 72 extends in the circumferential direction of the yoke 24.

[0051] The width H1 between the pair of lead-groove-forming surfaces 71 is smaller than the outer diameter D1 of the lead wire 35 in its original shape. Therefore, when the lead wire 35 passes between the pair of lead-groove-forming surfaces 71, it is sandwiched and crushed between the pair of lead-groove-forming surfaces 71, and is then pulled out of the lead groove 70 radially outward of the yoke 24 beyond the insulator base 51. In this manner, the lead groove 70 retains the lead wire 35 by an interference fit. Note that the "original shape of the lead wire 35" refers to the shape of the lead wire 35 before it is sandwiched and crushed between the pair of lead-groove-forming surfaces 71, and before it is retained in the lead groove 70 by an interference fit.

[0052] <Return groove> As shown in FIG. 4 , the other insulator base 51 of the two insulators 50 has a plurality of return grooves 80. The return grooves 80 open to the insulator end portion 51e. The return grooves 80 penetrate the insulator base 51 in the radial direction of the yoke 24. A first end of each return groove 80 opens to the inner circumferential surface 51a of the insulator base 51, and a second end of each return groove 80 opens to the outer circumferential surface 51b of the insulator base 51. Each return groove 80 is disposed adjacent to each of the pull-out grooves 70 in the circumferential direction of the insulator base 51. Each return groove 80 pulls the lead wires 35 drawn out from each pull-out groove 70 from the outer circumferential surface 51b side of the insulator base 51 back to the inner circumferential surface 51a side of the insulator base 51. In this way, the return groove 80 returns the lead wire 35 drawn out from the lead groove 70 to a position radially inward of the insulator base portion 51 of the yoke 24 .

[0053] As shown in FIG. 5, the return groove 80 has a pair of return groove forming surfaces 81 and a connecting surface 82. When the return groove 80 is viewed from the radial direction of the yoke 24, the pair of return groove forming surfaces 81 extend parallel to each other in the axial direction of the yoke 24 from the insulator end 51e. The pair of return groove forming surfaces 81 are located on both sides in the circumferential direction of the yoke 24, with the lead wire 35 sandwiched therebetween. The connecting surface 82 connects the ends of the pair of return groove forming surfaces 81 opposite the insulator end 51e. When the return groove 80 is viewed from the radial direction of the yoke 24, the connecting surface 82 extends in the circumferential direction of the yoke 24.

[0054] The length from the insulator end 51e to each return groove forming surface 81 is the same as the length from the insulator end 51e to each pull-out groove forming surface 71. The connection surface 82 of each return groove 80 is adjacent to the connection surface 72 of each pull-out groove 70 in the circumferential direction of the yoke 24.

[0055] The width H2 between the pair of return groove forming surfaces 81 is larger than the outer diameter D1 of the lead wire 35 in its original shape. Therefore, when the lead wire 35 passes between the pair of return groove forming surfaces 81, the lead wire 35 is pulled back from the return groove 80 toward the radially inner side of the yoke 24 beyond the insulator base 51 without being pinched and crushed between the pair of return groove forming surfaces 81. In this way, the return groove 80 retains the lead wire 35 with a clearance fit.

[0056] <Protrusion> 4, the other of the two insulators 50 has a plurality of protrusions 90 on the insulator base 51. Each protrusion 90 protrudes from a portion of the outer peripheral surface 51b of the insulator base 51 between each of the pull-out grooves 70 and each of the return grooves 80.

[0057] 5 and 6, the protrusion 90 has a locking surface 91 on the opposite side from the insulator end 51e. The locking surface 91 extends from the outer peripheral surface 51b of the insulator base 51 in the radial direction of the yoke 24. The locking surface 91 is flat. The locking surface 91 is positioned closer to the insulator end 51e than the connection surface 72 of the pull-out groove 70 and the connection surface 82 of the return groove 80.

[0058] The lead wire 35 drawn out from the lead groove 70 extends toward the return groove 80 while being locked by the locking surface 91 of the protrusion 90. In this manner, the lead wire 35 drawn out from the lead groove 70 is locked at a portion of the protrusion 90 opposite to the insulator end 51e.

[0059] [Operation of the first embodiment] Next, the operation of the first embodiment will be described while explaining the procedure for tying and fixing the lead wires 35 to the insulator 50.

[0060] 7 , when the lead wire 35 is bound and fixed to the insulator 50, the lead wire 35 is first pulled out from the lead groove 70 to a radially outer side of the yoke 24 beyond the insulator base 51 so that the lead wire 35 passes through the lead groove 70. At this time, the lead groove 70 holds the lead wire 35 in place with an interference fit. This prevents the lead wire 35 from slipping out of the lead groove 70.

[0061] 8, the lead wire 35 drawn out from the lead groove 70 is then bent in the circumferential direction of the yoke 24 toward the return groove 80. At this time, the lead wire 35 is bent in the circumferential direction of the yoke 24 so that the lead wire 35 is locked by the locking surface 91 of the protrusion 90.

[0062] 9, the lead wire 35 is then bent in the axial direction of the yoke 24 from the engagement portion with the protrusion 90 toward the insulator end portion 51e. At this time, the lead wire 35 is bent until a part of the portion of the lead wire 35 opposite the engagement portion with the protrusion 90 from the lead groove 70 overlaps with the return groove 80 in the radial direction of the yoke 24.

[0063] As shown in Figure 10, the lead wire 35 is then bent radially inward of the yoke 24 so that the lead wire 35 passes through the return groove 80. At this time, the return groove 80 retains the lead wire 35 with a clearance fit. This makes it easy for the lead wire 35 to pass inside the return groove 80. Furthermore, when the lead wire 35 is pulled back toward the inner circumferential surface 51a of the insulator base 51 through the return groove 80, interference with other lead wires 35 in the second coil end 282 can be easily avoided when the lead wire 35 is pulled from the second coil end 282 side while avoiding interference with the other lead wires 35.

[0064] 5, the lead wires 35 that have been pulled back through the return grooves 80 to a position radially inward of the yoke 24 relative to the insulator base 51 are then bent inside the insulator base 51 toward the opposite side of the lead grooves 70 in the circumferential direction of the yoke 24. As a result, the lead wires 35 that have been pulled back through the return grooves 80 to a position radially inward of the yoke 24 relative to the insulator base 51 extend along the inner circumferential surface 51a of the insulator base 51. This prevents the lead wires 35 from interfering with components that are radially outward of the yoke 24 relative to the insulator base 51.

[0065] In this way, the lead wires 35 are bound and fixed to the insulator 50. By being bound and fixed to the insulator 50, the lead wires 35 are fixed to the insulator 50 in a state in which tension is applied thereto.

[0066] The winding start portion of the winding portion 30 of the coil 28 is fixed as the winding wire 31 is wound around the teeth 25. Therefore, the winding start portion of the winding portion 30 is prevented from loosening. Furthermore, because the lead wire 35 is wound and fixed to the insulator 50, the winding end portion of the winding portion 30 is prevented from loosening.

[0067] [Effects of the first embodiment] The first embodiment can provide the following effects. (1-1) Because the lead-out groove 70 retains the lead-out wire 35 with an interference fit, unstable entanglement of the lead-out wire 35 with respect to the insulator 50 is avoided. Furthermore, because the return groove 80 retains the lead-out wire 35 with a clearance fit, the lead-out wire 35, which has been drawn from the lead-out groove 70 toward the outer circumferential surface 51b of the insulator base 51, can be easily pulled back toward the inner circumferential surface 51a of the insulator base 51 via the return groove 80. Therefore, when pulling the lead-out wire 35 back toward the inner circumferential surface 51a of the insulator base 51 via the return groove 80, interference with other lead-out wires 35 at the second coil end 282 can be easily avoided when the lead-out wire 35 is pulled from the second coil end 282 while avoiding interference with other lead-out wires 35. This facilitates the task of entanglement of the lead-out wire 35 with respect to the insulator 50. As a result, the work of tying and fixing the lead wire 35 to the insulator 50 can be easily performed while preventing the lead wire 35 from being tied and fixed to the insulator 50 from becoming unstable.

[0068] (1-2) Because the width H2 between the pair of return groove forming surfaces 81 is larger than the outer diameter D1 of the lead wire 35 in its original shape, the return groove 80 locks the lead wire 35 with a clearance fit. In this way, the pair of return groove forming surfaces 81 extend parallel to each other in the axial direction of the yoke 24 from the insulator end 51e. The width H2 between the pair of return groove forming surfaces 81 is larger than the outer diameter D1 of the lead wire 35 in its original shape. This configuration is suitable for the return groove 80 to lock the lead wire 35 with a clearance fit.

[0069] (1-3) Because the width H1 between the pair of lead-groove-forming surfaces 71 is smaller than the outer diameter D1 of the lead wire 35 in its original shape, the lead groove 70 locks the lead wire 35 with an interference fit. In this way, the pair of lead-groove-forming surfaces 71 extend parallel to each other in the axial direction of the yoke 24 from the insulator end 51e. The width H1 between the pair of lead-groove-forming surfaces 71 is smaller than the outer diameter D1 of the lead wire 35 in its original shape. This configuration is suitable for the lead groove 70 to lock the lead wire 35 with an interference fit.

[0070] (1-4) The lead wire 35 drawn from the lead groove 70 toward the outer peripheral surface 51b of the insulator base 51 is locked to the protrusion 90 at a location opposite the insulator end 51e. This further stabilizes the binding and fixation of the lead wire 35 to the insulator 50.

[0071] (1-5) For example, consider a case where the insulator 50 thermally expands. In this case, even if the lead-out groove 70 holds the lead-out wire 35 with an interference fit, the return groove 80 holds the lead-out wire 35 with a clearance fit, thereby mitigating the stress acting on the lead-out wire 35 from the insulator 50. This improves the durability of the lead-out wire 35, thereby improving the reliability of the stator 11 of the rotating electric machine 10.

[0072] [Second embodiment] A second embodiment of a stator for a rotating electrical machine will be described below with reference to Figures 11 and 12. In the embodiment described below, the same components as those in the first embodiment will be denoted by the same reference numerals, and redundant description will be omitted or simplified.

[0073] 11 and 12 , when the return groove 80 is viewed from the axial direction of the yoke 24, the pair of return groove forming surfaces 81 are inclined so as to gradually move away from the pull-out groove 70 from the outer peripheral surface 51b toward the inner peripheral surface 51a of the insulator base 51. The return groove forming surfaces 81 extend parallel to each other. When the lead wire 35 is pulled from the pull-out groove 70 toward the outer peripheral surface 51b of the insulator base 51 toward the inner peripheral surface 51a of the insulator base 51 via the return groove 80, the return groove forming surfaces 81 guide the lead wire 35 in a direction away from the pull-out groove 70.

[0074] As shown in FIG. 12 , the width H2 between the pair of return groove forming surfaces 81 is smaller than the outer diameter D1 of the lead wire 35 in its original shape. Therefore, the return groove 80 engages the lead wire 35 with an interference fit. Note that the "original shape of the lead wire 35" refers to the shape of the lead wire 35 before it is sandwiched between the pair of return groove forming surfaces 81 and crushed, i.e., the shape of the lead wire 35 before it is engaged with the return groove 80 with an interference fit. The width H1 between the pair of lead groove forming surfaces 71 is larger than the outer diameter D1 of the lead wire 35 in its original shape. Therefore, the lead groove 70 engages the lead wire 35 with a clearance fit.

[0075] [Effects of the second embodiment] The second embodiment can provide the following effects. (2-1) Because the width H2 between the pair of return groove forming surfaces 81 is smaller than the outer diameter D1 of the lead wire 35 in its original shape, the return groove 80 engages the lead wire 35 with an interference fit. This prevents the lead wire 35 from being unstably entangled with the insulator 50. When the return groove 80 is viewed from the axial direction of the yoke 24, the pair of return groove forming surfaces 81 are inclined, gradually moving away from the lead groove 70 as they extend from the outer peripheral surface 51b toward the inner peripheral surface 51a of the insulator base 51. Here, consider a case where the pair of return groove forming surfaces 81 extend from the outer peripheral surface 51b toward the inner peripheral surface 51a of the insulator base 51 at the same distance from the lead groove 70. Compared to this case, the lead wire 35 drawn from the lead groove 70 toward the outer peripheral surface 51b of the insulator base 51 can be more easily pulled back toward the inner peripheral surface 51a of the insulator base 51 via the return groove 80. Therefore, when pulling the lead wire 35 back toward the inner peripheral surface 51a of the insulator base 51 via the return groove 80, it is possible to easily avoid interference with other lead wires 35 when pulling the lead wire 35 from the second coil end 282 while avoiding interference with other lead wires 35. This makes it easier to bind and secure the lead wire 35 to the insulator 50. As described above, the lead wire 35 can be easily bound and secured to the insulator 50 while avoiding instability in the binding and securing of the lead wire 35 to the insulator 50.

[0076] (2-2) Because the width H1 between the pair of lead-groove-forming surfaces 71 is larger than the outer diameter D1 of the lead wire 35 in its original shape, the lead groove 70 retains the lead wire 35 with a clearance fit. Here, consider, for example, a case where the insulator 50 thermally expands. In this case, even if the return groove 80 retains the lead wire 35 with an interference fit, the lead groove 70 retains the lead wire 35 with a clearance fit, thereby mitigating the stress acting on the lead wire 35 from the insulator 50. This improves the durability of the lead wire 35, thereby improving the reliability of the stator 11 of the rotating electric machine 10.

[0077] (2-3) When the return groove 80 is viewed from the axial direction of the yoke 24, the pair of return groove forming surfaces 81 are inclined so as to gradually move away from the lead groove 70 from the outer peripheral surface 51b toward the inner peripheral surface 51a of the insulator base 51. Therefore, when the lead wire 35 is returned to the inner peripheral surface 51a of the insulator base 51 through the return groove 80, the winding equipment can be disposed radially outward of the insulator base 51. Therefore, for example, by disposing the winding equipment radially inward of the insulator base 51, it is possible to avoid a problem such as interference with the lead wire 35 of the coil 28 of another phase.

[0078] [Example of change] The above-described embodiments can be modified as follows: The above-described embodiments and the following modifications can be combined with each other within the scope of technical compatibility.

[0079] Fig. 13 shows a modification of the first embodiment. As shown in Fig. 13, when the return groove 80 is viewed from the radial direction of the yoke 24, of the pair of return groove forming surfaces 81, the return groove forming surface 81 located farther from the drawn groove 70 is inclined so as to gradually move away from the drawn groove 70 as it approaches the insulator end portion 51e.

[0080] This makes it possible to easily pass the lead wire 35 inside the return groove 80 when the lead wire 35, which has been drawn out from the lead groove 70 toward the outer peripheral surface 51b of the insulator base 51, is returned to the inner peripheral surface 51a of the insulator base 51 through the return groove 80. This makes it easier to bind and secure the lead wire 35 to the insulator 50. Furthermore, when returning the lead wire 35 to the inner peripheral surface 51a of the insulator base 51 through the return groove 80, the winding equipment can be disposed radially outward of the insulator base 51 from the yoke 24. This makes it possible to avoid problems such as interference with the lead wire 35 of the coil 28 of another phase, which may occur when the winding equipment is disposed radially inward of the insulator base 51 from the yoke 24.

[0081] 14 shows a modification of the first embodiment. As shown in FIG. 14, when the return groove 80 is viewed from the axial direction of the yoke 24, the pair of return groove forming surfaces 81 are inclined so as to gradually separate from the lead groove 70 from the outer peripheral surface 51b toward the inner peripheral surface 51a of the insulator base 51. A width H2 between the pair of return groove forming surfaces 81 is larger than the outer diameter D1 of the lead wire 35 in its original shape.

[0082] According to this, the width H2 between the pair of return groove forming surfaces 81 is larger than the outer diameter D1 of the lead wire 35 in its original shape, and therefore the return groove 80 retains the lead wire 35 with a clearance fit. When the return groove 80 is viewed from the axial direction of the yoke 24, the pair of return groove forming surfaces 81 are inclined so as to gradually move away from the lead groove 70 from the outer peripheral surface 51b toward the inner peripheral surface 51a of the insulator base 51. Here, consider, for example, a case in which the pair of return groove forming surfaces 81 extend from the outer peripheral surface 51b toward the inner peripheral surface 51a of the insulator base 51 while maintaining the same distance from the lead groove 70. Compared to this case, it is easier to pull the lead wire 35, which has been pulled from the lead groove 70 toward the outer peripheral surface 51b of the insulator base 51, back toward the inner peripheral surface 51a of the insulator base 51 via the return groove 80. Therefore, the operation of tying and fixing the lead wire 35 to the insulator 50 can be performed more easily.

[0083] In the second embodiment, the width H1 between the pair of lead-out groove forming surfaces 71 may be smaller than the outer diameter D1 of the lead-out wire 35 in its original shape. In other words, in the second embodiment, the lead-out groove 70 may lock the lead-out wire 35 by an interference fit.

[0084] In each of the above-described embodiments, the insulator base 51 does not necessarily have to have the protrusion 90 . In the above embodiments, the lead wires 35 on the winding end side drawn out from the winding unit 30 are electrically connected to each other to form a neutral point, but this is not limited to this. For example, the lead wires 35 on the winding end side drawn out from the winding unit 30 may be electrically connected to an external power supply via a connection terminal housed in the cluster block 40. In this case, parts of the winding wires on the winding start side drawn out from the winding unit 30 are electrically connected to each other to form a neutral point.

[0085] In each of the above embodiments, the rotor 12 is disposed inside the stator 11. However, the stator 11 may be disposed inside a cylindrical rotor 12. In this case, the teeth 25 extend radially outward from the outer peripheral surface of the yoke 24. In short, it is sufficient for the teeth 25 to extend radially from the outer peripheral surface of the yoke 24. When the stator 11 is disposed inside the rotor 12, the outer peripheral surface 51b of the insulator base 51 is a first peripheral surface located on the coil end side, and the inner peripheral surface 51a of the insulator base 51 is a second peripheral surface located on the opposite side from the coil end.

[0086] In each of the above-described embodiments, the winding 31 of the coil 28 of each phase may be wound around the tooth extensions 26 and the insulator extensions 53 of the insulators 50 by hand.

[0087] [Note] The technical ideas that can be understood from the above-described embodiment and modifications will be described below. <Appendix 1> a stator core having a cylindrical yoke and a plurality of teeth extending radially from a circumferential surface of the yoke; a coil formed by winding a winding around each of the teeth and including a coil end protruding from a core end surface, which is an end surface of the stator core positioned in the axial direction of the yoke; an insulator disposed opposite the core end surface and insulating between the coil end and the core end surface, The coil has a winding portion formed by winding the winding around the teeth in a concentrated winding manner, A lead wire on the winding end side, which is part of the winding, is drawn out from the winding portion, the insulator has a cylindrical insulator base portion disposed at a position overlapping the yoke in the axial direction, The insulator base is a first circumferential surface located on the coil end side; a second circumferential surface located on the opposite side to the coil end; a lead-out groove that opens at an insulator end portion that is an end portion of the insulator base portion opposite to the stator core, and has a first end that opens at the first circumferential surface and a second end that opens at the second circumferential surface, and leads the lead wires from the first circumferential surface side to the second circumferential surface side; a return groove that opens at an end of the insulator, has a first end that opens in the first circumferential surface and a second end that opens in the second circumferential surface, is disposed adjacent to the lead-out groove in the circumferential direction of the insulator base, and leads the lead wires drawn out from the lead-out groove from the second circumferential surface side to the first circumferential surface side, The lead-out groove engages the lead-out wire with an interference fit, A stator for a rotating electric machine, characterized in that the return groove retains the lead wire with a clearance fit.

[0088] <Appendix 2> the return groove has a pair of return groove forming surfaces located on both sides with the lead wire therebetween, the pair of return groove forming surfaces extend parallel to each other in the axial direction from the insulator end, The stator of a rotating electric machine described in <Appendix 1>, wherein the width between the pair of return groove forming surfaces is larger than the outer diameter of the lead wire in its original shape.

[0089] <Appendix 3> the return groove has a pair of return groove forming surfaces located on both sides with the lead wire therebetween, The stator of a rotating electric machine described in <Appendix 1>, characterized in that of the pair of return groove forming surfaces, the return groove forming surface located farther from the drawn-out groove is inclined so as to gradually move away from the drawn-out groove as it approaches the end of the insulator.

[0090] <Appendix 4> the return groove has a pair of return groove forming surfaces located on both sides with the lead wire therebetween, When the return groove is viewed from the axial direction, the pair of return groove forming surfaces are inclined so as to gradually move away from the pull-out groove from the second peripheral surface toward the first peripheral surface, The stator of a rotating electric machine described in <Appendix 1>, wherein the width between the pair of return groove forming surfaces is larger than the outer diameter of the lead wire in its original shape.

[0091] <Appendix 5> The lead groove has a pair of lead groove forming surfaces located on both sides with the lead wire therebetween, the pair of drawing groove forming surfaces extend parallel to each other in the axial direction from the end of the insulator, A stator for a rotating electric machine described in any one of <Appendix 1> to <Appendix 4>, characterized in that the width between the pair of lead-out groove forming surfaces is smaller than the outer diameter of the lead-out wire in its original shape.

[0092] <Appendix 6> a stator core having a cylindrical yoke and a plurality of teeth extending radially from a circumferential surface of the yoke; a coil formed by winding a winding around each of the teeth and including a coil end protruding from a core end surface, which is an end surface of the stator core positioned in the axial direction of the yoke; an insulator disposed opposite the core end surface and insulating between the coil end and the core end surface, The coil has a winding portion formed by winding the winding around the teeth in a concentrated winding manner, A lead wire on the winding end side, which is part of the winding, is drawn out from the winding portion, the insulator has a cylindrical insulator base portion disposed at a position overlapping the yoke in the axial direction, The insulator base is a first circumferential surface located on the coil end side; a second circumferential surface located on the opposite side to the coil end; a lead-out groove that opens at an insulator end portion that is an end portion of the insulator base portion opposite to the stator core, and has a first end that opens at the first circumferential surface and a second end that opens at the second circumferential surface, and leads the lead wires from the first circumferential surface side to the second circumferential surface side; a return groove that opens at an end of the insulator, has a first end that opens in the first circumferential surface and a second end that opens in the second circumferential surface, is disposed adjacent to the lead-out groove in the circumferential direction of the insulator base, and leads the lead wires drawn out from the lead-out groove from the second circumferential surface side to the first circumferential surface side, the return groove has a pair of return groove forming surfaces located on both sides with the lead wire therebetween, When the return groove is viewed from the axial direction, the pair of return groove forming surfaces are inclined so as to gradually move away from the pull-out groove from the second peripheral surface toward the first peripheral surface, A stator for a rotating electric machine, wherein a width between the pair of return groove forming surfaces is smaller than an outer diameter of the lead wire in its original shape.

[0093] <Appendix 7> The lead groove has a pair of lead groove forming surfaces located on both sides with the lead wire therebetween, The stator of a rotating electric machine according to <Appendix 6>, wherein the width between the pair of lead-out groove forming surfaces is larger than the outer diameter of the lead-out wire in its original shape.

[0094] <Appendix 8> the insulator base portion has a protrusion portion that protrudes from a portion of the second circumferential surface between the pull-out groove and the return groove, The stator of a rotating electric machine described in any one of <Appendix 1> to <Appendix 7>, characterized in that the lead wire drawn out from the lead groove is engaged with a portion of the protrusion opposite the end of the insulator. [Explanation of symbols]

[0095] 10...rotating electric machine, 11...stator, 23...stator core, 23b...second core end face which is the core end face, 24...yoke, 24a...inner circumferential surface which is the circumferential surface, 25...teeth, 28...coil, 30...winding portion, 31...winding, 35...lead wire, 50...insulator, 51...insulator base, 51a...inner circumferential surface which is the first circumferential surface, 51b...outer circumferential surface which is the second circumferential surface, 51e...insulator end, 70...drawing groove, 71...drawing groove forming surface, 80...return groove, 81...return groove forming surface, 90...protrusion, 282...second coil end which is the coil end.

Claims

1. a stator core having a cylindrical yoke and a plurality of teeth extending radially from a circumferential surface of the yoke; a coil formed by winding a winding around each of the teeth and including a coil end protruding from a core end surface, which is an end surface of the stator core positioned in the axial direction of the yoke; an insulator disposed opposite the core end surface and insulating between the coil end and the core end surface, The coil has a winding portion formed by winding the winding around the teeth in a concentrated winding manner, A lead wire on the winding end side, which is part of the winding, is drawn out from the winding portion, the insulator has a cylindrical insulator base portion disposed at a position overlapping the yoke in the axial direction, The insulator base is a first circumferential surface located on the coil end side; a second circumferential surface located on the opposite side to the coil end; a lead-out groove that opens at an insulator end portion that is an end portion of the insulator base portion opposite to the stator core, and has a first end that opens at the first circumferential surface and a second end that opens at the second circumferential surface, and through which the lead wires are led from the first circumferential surface side to the second circumferential surface side; a return groove that opens at an end of the insulator, has a first end that opens in the first circumferential surface and a second end that opens in the second circumferential surface, is disposed adjacent to the lead-out groove in the circumferential direction of the insulator base, and leads the lead wires drawn out from the lead-out groove from the second circumferential surface side to the first circumferential surface side, The lead-out groove engages the lead-out wire with an interference fit, A stator for a rotating electric machine, characterized in that the return groove retains the lead wire with a clearance fit.

2. the return groove has a pair of return groove forming surfaces located on both sides with the lead wire therebetween, the pair of return groove forming surfaces extend parallel to each other in the axial direction from the insulator end, 2. The stator of claim 1, wherein a width between the pair of return groove forming surfaces is larger than an outer diameter of the lead wire in its original shape.

3. the return groove has a pair of return groove forming surfaces located on both sides with the lead wire therebetween, 2. The stator of claim 1, wherein the return groove forming surface of the pair of return groove forming surfaces that is located farther from the drawn-out groove is inclined so as to gradually move away from the drawn-out groove as it approaches the end of the insulator.

4. the return groove has a pair of return groove forming surfaces located on both sides with the lead wire therebetween, When the return groove is viewed from the axial direction, the pair of return groove forming surfaces are inclined so as to gradually move away from the pull-out groove from the second circumferential surface toward the first circumferential surface, 2. The stator of claim 1, wherein a width between the pair of return groove forming surfaces is larger than an outer diameter of the lead wire in its original shape.

5. The lead groove has a pair of lead groove forming surfaces located on both sides with the lead wire therebetween, the pair of drawing groove forming surfaces extend parallel to each other in the axial direction from the end of the insulator, 5. The stator for a rotating electric machine according to claim 1, wherein a width between the pair of lead-out groove forming surfaces is smaller than an outer diameter of the lead-out wire in its original shape.

6. a stator core having a cylindrical yoke and a plurality of teeth extending radially from a circumferential surface of the yoke; a coil formed by winding a winding around each of the teeth and including a coil end protruding from a core end surface, which is an end surface of the stator core positioned in the axial direction of the yoke; an insulator disposed opposite the core end surface and insulating between the coil end and the core end surface, The coil has a winding portion formed by winding the winding around the teeth in a concentrated winding manner, A lead wire on the winding end side, which is part of the winding, is drawn out from the winding portion, the insulator has a cylindrical insulator base portion disposed at a position overlapping the yoke in the axial direction, The insulator base is a first circumferential surface located on the coil end side; a second circumferential surface located on the opposite side to the coil end; a lead-out groove that opens at an insulator end portion that is an end portion of the insulator base portion opposite to the stator core, and has a first end that opens at the first circumferential surface and a second end that opens at the second circumferential surface, and through which the lead wires are led from the first circumferential surface side to the second circumferential surface side; a return groove that opens at an end of the insulator, has a first end that opens in the first circumferential surface and a second end that opens in the second circumferential surface, is disposed adjacent to the lead-out groove in the circumferential direction of the insulator base, and leads the lead wires drawn out from the lead-out groove from the second circumferential surface side to the first circumferential surface side, the return groove has a pair of return groove forming surfaces located on both sides with the lead wire therebetween, When the return groove is viewed from the axial direction, the pair of return groove forming surfaces are inclined so as to gradually move away from the pull-out groove from the second circumferential surface toward the first circumferential surface, A stator for a rotating electric machine, wherein a width between the pair of return groove forming surfaces is smaller than an outer diameter of the lead wire in its original shape.

7. The lead groove has a pair of lead groove forming surfaces located on both sides with the lead wire therebetween, 7. The stator for a rotating electric machine according to claim 6, wherein a width between the pair of lead-out groove forming surfaces is larger than an outer diameter of the lead wire in its original shape.

8. the insulator base portion has a protrusion portion that protrudes from a portion of the second circumferential surface between the pull-out groove and the return groove, 7. The stator for a rotating electric machine according to claim 1, wherein the lead wires drawn out from the lead grooves are anchored to portions of the protrusions on the opposite side to the end of the insulator.

Images