Stator of rotary electric machine and method for manufacturing stator

Abstract

To provide a stator of a rotary electric machine and a method for manufacturing the stator with which it is possible to easily fix a cylindrical cover member to the inner circumferential part of a stator core without requiring complex processing.SOLUTION: A stator 10 comprises an annular stator core 14, a coil 15, and a cylindrical cover member. The stator core 14 includes a plurality of teeth arranged in the circumferential direction, and a plurality of slots 31 formed between the teeth that are adjacent in the circumferential direction. The coil 15 has a plurality of conductors 15a wound around respective teeth through the slots 31. The cover member is inserted and disposed in the inner circumferential part of the stator core 14 so that the outer circumferential surface faces an opening 40 on the radial inside of the plurality of slots 31. Each slot 31 is filled with a foamable insulating member 43 covering the outer surfaces of the plurality of conductors 15a of the coil 15 and adhered to the outer circumferential surface of the cover member through the opening 40 of the slot 31.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a stator of a rotating electrical machine and a method for manufacturing the stator.

Background Art

[0002] A rotating electrical machine such as an electric motor or a generator includes a stator and a rotor that rotates relative to the stator. The stator includes a stator core and a coil wound around the stator core. The stator core is integrally formed with, for example, a cylindrical back yoke (yoke) and a plurality of teeth protruding radially inward from the back yoke. Slots are formed between a plurality of adjacent teeth in the circumferential direction so as to open radially inward. A plurality of conductor portions of the coil are inserted into each slot.

[0003] In addition, as a stator of such a rotating electrical machine, a cylindrical cover member (sleeve) is inserted and arranged on the inner peripheral portion of an annular stator core, and the opening of each slot is covered from the radially inner side by the outer peripheral surface of the cover member (see, for example, Patent Document 1).

[0004] In the stator described in Patent Document 1, engagement holes are formed at a plurality of locations of the cylindrical cover member, and locking protrusions that are fitted into the engagement holes of the cover member are formed on the inner peripheral surface of the stator core. The cover member is fixed to the inner peripheral surface of the stator core by fitting the engagement holes to the corresponding locking protrusions of the stator core.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the stator described in Patent Document 1, in order to fix a cylindrical cover member to the inner peripheral surface of the stator core, it is necessary to form a plurality of engagement holes in the cover member and form locking protrusions on the inner peripheral surface of the stator core. Therefore, in the case of the stator described in Patent Document 1, it is necessary to perform complicated processing on the cover member and the stator core, and there is room for improvement in terms of production efficiency.

[0007] Therefore, the present invention aims to provide a stator of a rotating electrical machine and a method for manufacturing the stator that can easily fix a cylindrical cover member to the inner peripheral portion of a stator core without requiring complicated processing.

Means for Solving the Problems

[0008] The stator of the rotating electrical machine and the method for manufacturing the stator according to the present invention adopt the following configuration in order to solve the above problems. That is, the stator of the rotating electrical machine according to the present invention includes an annular stator core (for example, the stator core 14 in the embodiment) having a plurality of teeth (for example, the teeth 28 in the embodiment) arranged in the circumferential direction and a plurality of slots (for example, the slots 31 in the embodiment) formed between the adjacent teeth in the circumferential direction, a coil (for example, the coil 15 in the embodiment) in which a plurality of conductor portions (for example, the conductor portions 15a in the embodiment) are wound around each of the teeth through the slots, and a cylindrical cover member (for example, the annular partition wall 37 in the embodiment) inserted and disposed in the inner peripheral portion of the stator core so that an outer peripheral surface faces openings (for example, the opening 40 in the embodiment) on the radially inner side of the plurality of slots. Each of the slots is loaded with a foamed insulating member (for example, the foamed insulating member 43 in the embodiment) that covers outer surfaces of the plurality of conductor portions of the coil and is adhered to the outer peripheral surface of the cover member through the opening.

[0009] With the above configuration, the foamable insulating member is adhered to the outer peripheral surface of the cylindrical cover member through the opening of each slot. As a result, the cover member is fixed to the foamable insulating members in the respective slots through the openings of the plurality of slots. Further, the conductor portions of the coils accommodated and arranged in each slot are electrically insulated by the foamable insulating members. When this configuration is adopted, it is not necessary to perform complicated machining for fixing both to the cover member and the stator core, and moreover, the cylindrical cover member can be easily fixed to the inner peripheral portion of the stator core.

[0010] It is desirable that the foamable adhesive be disposed on the outer surface of the foamable insulating member.

[0011] In this case, by covering the outer surfaces of the plurality of conductor portions of the coil with the foamable insulating member, inserting them into the corresponding slots, and causing the foamable adhesive to foam, the cover member can be easily and surely fixed to the foamable insulating members in the plurality of slots by the foamable adhesive.

[0012] The plurality of slots may be configured to form a coolant passage for flowing coolant from one end side in the axial direction of the stator core to the other end side.

[0013] In this case, when the coolant flows in the slot, the conductor portions of the coils inserted and arranged in the slot are efficiently cooled by the coolant. At this time, the outflow of the coolant from the slot radially inward is blocked by the cylindrical cover member. Also, at this time, the opening of the slot is blocked by the foamable insulating member, and the portion of the outer peripheral surface of the cover member where the pressure of the coolant acts is reinforced by the foamable insulating member. Therefore, deformation of the cover member can be suppressed without increasing the overall wall thickness of the cover member. Thus, when this configuration is adopted, the wall thickness of the cover member can be reduced, the gap between the stator and the rotor can be narrowed, and the magnetic performance of the rotating electrical machine can be enhanced.

[0014] Moreover, a method for manufacturing a stator of a rotating electrical machine according to the present invention includes an annular stator core having a plurality of teeth arranged in the circumferential direction and a plurality of slots formed between the adjacent teeth in the circumferential direction, a coil in which a plurality of conductor portions are wound around each of the teeth through the slots, and a cylindrical cover member inserted and disposed on the inner peripheral portion of the stator core so that an outer peripheral surface faces openings on the radially inner side of the plurality of slots. The method for manufacturing a stator of a rotating electrical machine is characterized in that, with the outer surfaces of the plurality of conductor portions of the coil covered with a foamable insulating member, the plurality of conductor portions are inserted into the slots together with the foamable insulating member, and then the foamable insulating member is foamed to bond the foamable insulating member to the outer peripheral surface of the cover member through the openings of the slots.

[0015] In this case, by simply covering the outer surfaces of the plurality of conductor portions of the coil with a foamable insulating member, inserting them into the corresponding slots, and foaming the foamable insulating member, the cylindrical cover member can be adhesively fixed to the foamable insulating member in the plurality of slots through the openings of the slots.

[0016] Furthermore, a rod-shaped spacer member (for example, the spacer member 45 in the embodiment) that extends substantially along the conductor portion may be disposed radially inward of the conductor portion disposed most radially inward in the slot. The outer surfaces of the spacer member and the plurality of conductor portions are covered with the foamable insulating member, and the spacer member and the plurality of conductor portions are inserted into the slots together with the foamable insulating member. Then, the foamable insulating member is foamed to bond the foamable insulating member to the outer peripheral surface of the cover member through the openings of the slots.

[0017] In this case, the outer surfaces of the spacer member and the plurality of conductor portions of the coil are covered with a foamable insulating member, and in this state, the foamable insulating member is foamed within the corresponding slots, so that the plurality of conductor portions can be arranged at appropriate positions radially outside the slots. Also, in this case, the pressure of the coolant acts less easily on the radially outer end surfaces of the conductor portions that are the most radially outside within the slots. For this reason, it becomes difficult for the plurality of conductor portions to be pressed radially inward by the coolant. Furthermore, when the portion of the foamable insulating member that is located radially inside the slots foams, the inner side (the side away from the opening of the slot) of the foamable insulating member is supported by the spacer member. For this reason, when the foamable insulating member foams, a part of the foamable insulating member expands and displaces toward the opening of the slot while the inner side is supported by the spacer member. Therefore, when this configuration is adopted, a part of the foamable insulating member passes through the opening of the slot, and a part of it is surely adhered to the cover member through the opening.

[0018] After foaming the foamable insulating member and adhering the foamable insulating member to the outer peripheral surface of the cover member through the opening of the slot, the spacer member may be removed from the inside of the foamable insulating member.

[0019] In this case, by removing the rod-shaped spacer member after foaming the foamable insulating member, it becomes possible to reduce the weight of the stator. Also, after removing the rod-shaped spacer, a communication hole along the axial direction of the stator is formed inside the foamable insulating member. By using this communication hole as a coolant passage, it becomes possible to efficiently cool the conductor portions of the coil.

Advantages of the Invention

[0020] The stator of the rotating electrical machine according to the present invention has a foamed insulating member loaded in each slot of the stator core, which covers the outer surfaces of a plurality of conductor portions of a coil and is adhered to the outer peripheral surface of a cover member through the opening of the slot. Therefore, the cylindrical cover member is adhered to the foamed insulating members in the plurality of slots through the openings of the slots. Accordingly, when the stator according to the present invention is adopted, the cylindrical cover member can be easily fixed to the inner peripheral portion of the stator core without requiring complicated processing.

[0021] The manufacturing method of the stator of the rotating electrical machine according to the present invention is as follows: with the outer surfaces of a plurality of conductor portions of a coil covered by a foamed insulating member, the plurality of conductor portions are inserted into the slots together with the foamed insulating member, and then the foamed insulating member is foamed to adhere the foamed insulating member to the outer peripheral surface of the cover member through the slots. Therefore, by simply covering the outer surfaces of the plurality of conductor portions with the foamed insulating member, inserting them into the corresponding slots, and foaming the foamed insulating member, the cylindrical cover member can be adhered and fixed to the foamed insulating members in the plurality of slots through the openings of the slots. Accordingly, when the manufacturing method of the stator according to the present invention is adopted, the cylindrical cover member can be easily fixed to the inner peripheral portion of the stator core without requiring complicated processing.

Brief Description of the Drawings

[0022]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0023] Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view of a rotating electrical machine 1 of the present embodiment. The rotating electrical machine 1 of this embodiment includes a stator 10 and a rotor 11. The stator 10 and the rotor 11 are housed inside a rotating electrical machine case 12. The stator 10 is fixed inside the rotating electrical machine case 12 by fastening with bolts 13 or the like. The stator 10 includes a cylindrical stator core 14 and a plurality of coils 15 wound around the stator core 14. The rotor 11 is rotatably disposed radially inside the stator core 14 (stator 10).

[0024] Permanent magnets (not shown) are attached near the outer peripheral surface of the rotor 11. Further, the rotor 11 is integrally rotatably supported on a rotating shaft 17 via a sleeve 16. The rotating shaft 17 serves as an output shaft when the rotating electrical machine 1 is used as a motor, and serves as a power input shaft when the rotating electrical machine 1 is used as a generator. The rotating shaft 17 and the sleeve 16 are rotatably supported on the rotating electrical machine case 12 via bearings 18. In the following description, the direction parallel to the rotation axis C of the rotor 11 is referred to as the axial direction, the rotation direction of the rotor 11 is referred to as the circumferential direction, and the radial direction of the rotor 11 orthogonal to the axial direction and the circumferential direction is referred to as the radial direction.

[0025] Annular first side case 19 and second side case 20 are disposed on one end side and the other end side in the axial direction of the stator core 14. The main parts of the first side case 19 and the second side case 20 are formed by the rotating electrical machine case 12.

[0026] The first side case 19 covers, from the outside, one axial end face of the stator core 14 and the exposed portion of the coil 15 protruding from that end face. The first side case 19 forms an annular first liquid chamber 21 together with one axial end face of the stator core 14. An introduction port 24 for introducing the coolant 23 into the first liquid chamber 21 is formed in the first side case 19. The introduction port 24 is connected to the circulation circuit 25 of the coolant 23. The coolant 23 introduced into the first liquid chamber 21 cools the exposed portion of the coil 15 protruding from one end face of the stator core 14, and then passes through the inside of the stator core 14 and flows into the other end side in the axial direction of the stator core 14.

[0027] The second side case 20 covers, from the outside, the other axial end face of the stator core 14 and the exposed portion of the coil 15 protruding from that end face. The second side case 20 forms an annular second liquid chamber 22 together with the other axial end face of the stator core 14. The coolant 23 introduced into the first liquid chamber 21 flows into the second liquid chamber 22 through the inside of the stator core 14. The coolant 23 introduced into the second liquid chamber 22 cools the exposed portion of the coil 15 protruding from the other end face of the stator core 14. A discharge port 26 for discharging the coolant 23 in the second liquid chamber 22 to the outside is formed in the second side case 20. The discharge port 26 is connected to the circulation circuit 25 of the coolant 23. The coolant 23 that has cooled the coil 15 in the second liquid chamber 22 is returned from the discharge port 26 to the circulation circuit 25.

[0028] A feed pump P is connected in the middle of the circulation circuit 25. A heat exchanger OC that cools the coolant 23 by heat exchange with the outside air is connected upstream of the feed pump P in the circulation circuit 25. The downstream side of the feed pump P is connected to the introduction port 24. Also, the upstream side of the heat exchanger OC in the circulation circuit 25 is connected to the discharge port 26.

[0029] Figure 2 is a cross-sectional view taken along line II-II of Figure 1 of the rotating electrical machine 1. The stator core 14 is formed, for example, by axially laminating a plurality of electromagnetic steel sheets. As shown in FIG. 2, the stator core 14 is integrally formed with a cylindrical back yoke 27 and a plurality of teeth 28 that project radially inward from the inner peripheral portion of the back yoke 27. The back yoke 27 is formed such that the center of the cylinder coincides with the rotation axis C.

[0030] The teeth 28 are arranged at intervals in the circumferential direction. The teeth 28 are formed in a T shape when viewed from the axial direction. That is, the teeth 28 are integrally formed with a tooth body 29 that projects radially inward from the inner peripheral portion of the back yoke 27 and a flange portion 30 that projects from the inner radial end of the tooth body 29 to both sides in the circumferential direction.

[0031] A slot 31 with an open inner diameter is formed between adjacent teeth 28 in the circumferential direction. The slot 31 is formed surrounded by the opposing side walls of adjacent teeth 28 and the inner peripheral wall of the back yoke 27. The side walls of each tooth 28 are formed by the side portion of the tooth body 29 and the side portion of the flange portion 30. The portion of the slot 31 formed by the side portions of the left and right tooth bodies 29 has a substantially constant width. Also, the width of the portion of the slot 31 formed by the side portions of the left and right flange portions 30 is narrower than the width of the portion formed by the side portions of the left and right tooth bodies 29. Note that the inner diameter opening 40 of each slot 31 is formed sandwiched between the tip portions of the flange portions 30 on the left and right (both sides in the circumferential direction) of the slot 31.

[0032] The coils 15 are provided, for example, in three phases of U-phase, V-phase, and W-phase. The coil 15 is configured, for example, by connecting a plurality of segment coils to each other. The conductor portion 15a of the coil 15 has the outer surface of a metal core wire 41 covered by an insulating coating 42. The conductor portion 15a of the coil 15 is formed by a flat wire. That is, the cross-sectional shape of each conductor portion 15a is formed in a substantially rectangular shape.

[0033] As shown in FIG. 2, a plurality of conductor portions 15a of the coil 15 inserted into the same slot 31 are arranged in a row along the radial direction. In the present embodiment, for example, five conductor portions 15a are inserted into the same slot 31. However, the number of conductor portions 15a inserted into the same slot 31 is not limited to this, and can be arbitrarily set.

[0034] A plurality of conductor portions 15a inserted and arranged in each slot 31 are bundled so as to be arranged in parallel in a row, and their surroundings are covered by a sheet of the foaming insulating member 43. The foaming insulating member 43 can adopt, for example, a structure in which a foaming adhesive is arranged (applied) on the surface of an electrically insulating base sheet (the surface facing outward in a state of wrapping the conductor portion 15a), and a non-foaming adhesive is arranged (applied) on the back surface of the base sheet. The foaming insulating member 43 is inserted and arranged in the corresponding slot 31 together with these conductor portions 15a in a state of covering the surroundings of the plurality of conductor portions 15a. The foaming insulating member 43 foams in the corresponding slot 31 by performing heat treatment or the like later. The behavior and the like of the foaming insulating member 43 during foaming will be described in detail later.

[0035] Even after the conductor portion 15a of the coil 15 and the foaming insulating member 43 are arranged in the slot 31 as described above, a gap for communicating the one end side and the other end side in the axial direction of the stator core 14 is secured inside the slot 31. This gap constitutes a coolant passage 44 for flowing the coolant introduced into the first liquid chamber 21 toward the second liquid chamber 22 side. Specifically, the gap constituting the coolant passage 44 is, for example, a gap between the inner surface of the foaming insulating member 43 and the conductor portion 15a, a gap between adjacent conductor portions 15a, a gap between the outer surface of the foaming insulating member 43 and the inner wall of the slot 31, and the like. The coolant 23 flowing through the coolant passage 44 in the slot 31 absorbs the heat of the conductor portion 15a of the coil 15.

[0036] Note that on the surfaces of each conductor portion 15a disposed within each slot 31 that face radially inward and radially outward, concave grooves 50 extending along the axial direction of the stator core 14 are formed. The concave grooves 50 are formed to be recessed in a substantially arc shape toward the central region in the width direction of the conductor portion 15a. When a plurality of conductor portions 15a are disposed in the slot 31 together with the foamed insulating member 43, the concave grooves 50 form gaps (coolant passages 44) extending substantially along the axial direction between the end faces of the conductor portions 15a adjacent in the radial direction and between the end face of the conductor portion 15a and the inner surface of the foamed insulating member 43.

[0037] As shown in FIG. 1, the first side case 19 on one end side in the axial direction of the stator core 14 includes a first inner peripheral wall 32 facing the first liquid chamber 21. The first inner peripheral wall 32 protrudes cylindrically from the radially inner end of the end side wall 33 of the first side case 19 located at the outer axial end of the first liquid chamber 21 toward one end face in the axial direction of the rotor 11. In the case of the present embodiment, the first inner peripheral wall 32 is composed of a peripheral wall main body portion 12a integrally formed with the rotating electrical machine case 12 (end side wall 33) and a separate cylindrical member 34 attached to the outer peripheral surface on the extending end side of the peripheral wall main body portion 12a. The space between the peripheral wall main body portion 12a and the cylindrical member 34 is sealed by an annular seal member 60. However, the first inner peripheral wall 32 may be entirely integrally formed with the rotating electrical machine case 12 (end side wall 33).

[0038] Also, the second side case 20 on the other end side in the axial direction of the stator core 14 includes a second inner peripheral wall 35 facing the second liquid chamber 22. The second inner peripheral wall 35 protrudes cylindrically from the radially inner end of the end side wall 36 of the second side case 20 located at the outer axial end of the second liquid chamber 22 toward the other end face in the axial direction of the rotor 11. In the case of the present embodiment, the second inner peripheral wall 35 is integrally formed with the rotating electrical machine case 12 (end side wall 36). However, the second inner peripheral wall 35 may be configured by a peripheral wall main body portion integral with the rotating electrical machine case 12 (end side wall 36) and a separate cylindrical member, similar to the first inner peripheral wall 32.

[0039] On the outer peripheral surfaces of the outer peripheral surface of the first inner peripheral wall 32 of the first side case 19 and the outer peripheral surface of the second inner peripheral wall 35 of the second side case 20, an annular partition wall 37, which is a cylindrical cover member, is installed. The annular partition wall 37 is formed of, for example, a resin material. However, the annular partition wall 37 can also be formed of other materials such as a metal material. The annular partition wall 37 has a first end portion 37f facing the inside of the first liquid chamber 21, a second end portion 37s facing the inside of the second liquid chamber 22, and a partition wall main body portion 37b between the first end portion 37f and the second end portion 37s and facing the inner peripheral surface of the stator core 14. The first end portion 37f is formed with the same inner diameter as the partition wall main body portion 37b. The second end portion 37s has a reduced diameter in a stepped manner with respect to the partition wall main body portion 37b in the middle of the extending direction.

[0040] The inner peripheral surface of the first end portion 37f is slidably fitted to the outer peripheral surface of the cylindrical member 34 of the first inner peripheral wall 32. An annular groove 38f is formed on the outer peripheral surface of the cylindrical member 34, and an annular seal member 39f such as an O-ring is attached to the annular groove 38f. The space between the cylindrical member 34 (first inner peripheral wall 32) and the first end portion 37f (annular partition wall 37) is hermetically sealed by the seal member 39f. In the present embodiment, the first end portion 37f constitutes a guide member that guides the coolant in the first liquid chamber 21 to the opening of the slot 31 on one end side in the axial direction of the stator core 14 inside the first liquid chamber 21.

[0041] The inner peripheral surface of the reduced diameter portion of the second end portion 37s is slidably fitted to the outer peripheral surface of the second inner peripheral wall 35. An annular groove 38s is formed on the outer peripheral surface of the second inner peripheral wall 35, and an annular seal member 39s such as an O-ring is attached to the annular groove 38s. The space between the second inner peripheral wall 35 and the second end portion 37s (annular partition wall 37) is hermetically sealed by the seal member 39s.

[0042] The annular partition wall 37 has its first end portion 37f fitted in a liquid-tight manner to the first inner peripheral wall 32 of the first side case 19 and its second end portion 37s fitted in a liquid-tight manner to the second inner peripheral wall 35 of the second side case 20 as described above. The annular partition wall 37 partitions the radially inner region of the stator core 14 attached inside the rotating electric machine case 12 from the outer peripheral surface of the rotor 11. Therefore, even if the coolant 23 leaks from the slot 31 of the stator core 14 into the radially inner region, it is possible to prevent the coolant 23 from flowing into the outer peripheral surface side of the rotor 11.

[0043] Also, on the outer peripheral surface of the first end portion 37f of the annular partition wall 37, it bulges radially outward from the outer peripheral surface of the partition wall main body portion 37b. The end portion on the stator core 14 side of this bulging portion stands upright radially outward in a stepped manner with respect to the outer peripheral surface of the partition wall main body portion 37b. This upright end face is in contact with the end face on one axial end side of the stator core 14.

[0044] As shown in FIG. 2, the outer peripheral surface of the partition wall main body portion 37b of the annular partition wall 37 is maintained in contact with the inner peripheral surface of the stator core 14. Also, the inner peripheral surface of the partition wall main body portion 37b of the annular partition wall 37 faces the outer peripheral surface of the rotor 11 with a minute gap therebetween so as not to be in contact.

[0045] Here, the foamed insulating member 43 housed and arranged in each slot 31 of the stator core 14 together with the plurality of conductor portions 15a of the coil 15 is adhered to a part of the inner wall of the slot 31 when the foamed adhesive on the outer surface side foams due to heating or the like. At this time, the portion of the foamed adhesive of the foamed insulating member 43 located at the radially inner end of the slot 31 intrudes into the radially inner opening 40 of the slot 31 due to foaming and is adhered to the outer peripheral surface of the annular partition wall 37 through the opening 40. As a result, the peripheral wall main body portion 12a of the annular partition wall 37 is adhesively fixed to the foamed insulating members 43 inside the plurality of slots 31 through the openings 40 of the slots 31.

[0046] Next, a specific manufacturing method of the stator 10 (a method of fixing the annular partition wall 37 to the stator core 14) will be described. Figure 3 is a cross-sectional view similar to FIG. 2 during one step of manufacturing. Further, FIG. 4 is an enlarged cross-sectional view of a part of FIG. 2 after manufacturing. First, a bundle of a plurality of conductor portions 15a of the coil 15 covered on the outside by the foamed insulating member 43 is inserted into each corresponding slot 31 of the stator core 14, and the peripheral wall main body portion 12a of the annular partition wall 37 is inserted and arranged on the inner peripheral portion of the stator core 14. When covering the outside of the plurality of conductor portions 15a with the foamed insulating member 43, as shown in FIG. 3, a rod-shaped spacer member 45 is arranged radially inward of the one that is located most radially inward when housed in the slot 31 among the plurality of conductor portions 15a. As the spacer member 45, a rod-shaped member that extends linearly along the conductor portion 15a arranged in the slot 31 (along the axial direction of the stator core 14) can be used. The spacer member 45, together with the plurality of conductor portions 15a, has its outer surface covered by the sheet-shaped foamed insulating member 43. In the present embodiment, a spacer member 45 having a circular cross-section that extends linearly along the axial direction is adopted.

[0047] Next, in this state, the foamed insulating member 43 (foamed adhesive) in each slot 31 is foamed by heating or the like. When the foamed insulating member 43 (foamed adhesive) foams in the slot 31, the outer surface of the foamed insulating member 43 is adhered to a part of the inner wall of the slot 31, and a part of the foamed insulating member 43 penetrates into the opening 40 of the slot 31, and a part of it is adhered to the outer peripheral surface of the annular partition wall 37 through the opening 40.

[0048] After this, waiting for the completion of the foaming of the foamed insulating member 43 (foamed adhesive) in the slot 31, the rod-shaped spacer member 45 is axially pulled out from the foamed insulating member 43. As a result, a gap at least corresponding to the cross-section of the spacer member 45 is formed between the foamed insulating member 43 and the most radially inner conductor portion 15a, and a coolant passage 44 with a sufficient cross-sectional area is ensured.

[0049] When a current continuously flows through the coil 15 during operation of the rotating electrical machine 1 configured as described above, the coil 15 generates heat and becomes high in temperature. At this time, the coolant 23 is introduced into the first liquid chamber 21 of the rotating electrical machine 1 from the circulation circuit 25 through the introduction port 24. The coolant 23 introduced into the first liquid chamber 21 cools the one-end side region of the coil 15 exposed to the outside from one axial end side of the stator core 14 by flowing in the first liquid chamber 21. Further, the coolant 23 flows from one axial end side to the other end side through the plurality of slots 31 (coolant passages 44 in the slots 31) of the stator core 14 and flows into the second liquid chamber 22. The coolant flowing in the slot 31 cools the conductor portion 15a of the coil 15 inserted in the slot 31. Further, the coolant 23 flowing into the second liquid chamber 22 cools the other-end side region of the coil 15 exposed to the outside from the other axial end side of the stator core 14, and then is returned to the circulation circuit 25 through the discharge port 26.

[0050] As described above, the stator 10 of the rotating electrical machine 1 is always immersed in the coolant 23 in the rotating electrical machine case 12, and the coolant 23 in the rotating electrical machine case 12 is replaced through the circulation circuit 25 in that state. Therefore, the coil 15 of the stator 10 is efficiently cooled by the coolant 23.

[0051] As described above, in the stator 10 of the rotating electrical machine 1 of the present embodiment, a foamed insulating member 43 that covers the outer surfaces of the plurality of conductor portions 15a of the coil 15 and is adhered to the outer peripheral surface of the annular partition wall 37 (cover member) through the opening 40 of the slot 31 is loaded in each slot 31 of the stator core 14. For this reason, the annular partition wall 37 (cover member) is adhered to the foamed insulating members 43 in the plurality of slots 31 through the openings 40 of the respective slots 31. Therefore, when the stator 10 of the rotating electrical machine 1 of the present embodiment is adopted, the annular partition wall 37 (cover member) can be easily and firmly fixed to the inner peripheral portion of the stator core 14 without requiring complicated machining for fixing the annular partition wall 37 (cover member) to the stator core 14.

[0052] In addition, the stator 10 of the present embodiment can not only fix the annular partition wall 37 (cover member) by the foaming insulating member 43 in each slot 31, but also reliably insulate the peripheral region of the conductor portion 15a of the coil 15 by the foaming insulating member 43. When the stator 10 of the present embodiment is adopted, different from the case where the annular partition wall 37 (cover member) is fixed to the inner peripheral surface of the stator core 14 by a dedicated adhesive, the annular partition wall 37 (cover member) can be simultaneously fixed to the inner peripheral surface of the stator core 14 during the mounting process of the foaming insulating member 43 for insulating the peripheral region of the conductor portion 15a of the coil 15. Therefore, when the stator 10 of the rotating electric machine 1 of the present embodiment is adopted, the manufacturing of the stator 10 can be facilitated.

[0053] Moreover, the stator 10 of the rotating electric machine 1 of the present embodiment employs a foaming insulating member 43 in which a foaming adhesive is disposed on the outer surface. For this reason, the outer surfaces of the plurality of conductor portions 15a of the coil 15 are covered by the foaming insulating member 43, and these are inserted into the corresponding slots 31 and the foaming adhesive is foamed, so that the annular partition wall 37 (cover member) can be easily and reliably fixed to the foaming insulating members 43 in the plurality of slots 31 by the foaming adhesive.

[0054] Furthermore, the stator 10 of the rotating electric machine 1 of the present embodiment forms a coolant passage 44 through which the coolant 23 flows from one end side in the axial direction of the stator core 14 to the other end side inside the plurality of slots 31. For this reason, the conductor portion 15a of the coil 15 inserted and disposed in the slot 31 can be efficiently cooled by the coolant 23. Also, in the case of this configuration, since the outflow of the coolant 23 from the slot 31 to the outer peripheral surface of the rotor 11 can be blocked by the annular partition wall 37 (cover member), the inconvenience that the rotation of the rotor 11 is inhibited due to a large amount of the coolant 23 flowing into the outer peripheral surface of the rotor 11 can be eliminated. In addition, in this configuration, the opening 40 of each slot 31 is blocked by the foaming insulating member 43, and the portion where the pressure of the coolant 23 acts on the outer peripheral surface of the partition body portion 37b of the annular partition wall 37 is reinforced by the adhesive portion of the foaming insulating member 43. Therefore, without increasing the thickness of the partition body portion 37b of the annular partition wall 37, it is possible to suppress the deformation of the partition body portion 37b due to the pressure of the coolant 23. Therefore, when the stator 10 of the present embodiment is adopted, the thickness of the annular partition wall 37 can be reduced, the gap between the stator 10 and the rotor 11 can be narrowed, and the magnetic performance of the rotating electrical machine 1 can be enhanced.

[0055] Moreover, the manufacturing method of the stator 10 of the present embodiment described above is such that, with the outer surfaces of the plurality of conductor portions 15a of the coil 15 covered by the foaming insulating member 43, the plurality of conductor portions 15a are inserted into the slot 31 together with the foaming insulating member 43, and then the foaming insulating member 43 is foamed so that the foaming insulating member 43 adheres to the outer peripheral surface of the annular partition wall 37 (cover member) through the opening 40 of the slot 31. For this reason, by simply covering the outer surfaces of the plurality of conductor portions 15a with the foaming insulating member 43, inserting them into the corresponding slots 31, and foaming the foaming insulating member 43, the annular partition wall 37 (cover member) can be adhesively fixed to the foaming insulating member 43 in the plurality of slots 31 through the openings 40 of the slots 31. Therefore, when the manufacturing method of the stator 10 of the present embodiment is adopted, the annular partition wall 37 (cover member) can be easily and firmly fixed to the inner peripheral portion of the stator core 14 without requiring complicated machining for fixing the annular partition wall 37 (cover member) to the stator core 14.

[0056] Further, in the method for manufacturing the stator 10 of the present embodiment, a rod-shaped spacer member 45 that extends substantially along the conductor portion 15a is disposed radially inward of the conductor portion 15a that is disposed most radially inward within the slot 31, and the outer surfaces of the spacer member 45 and the plurality of conductor portions 15a are covered with the foamable insulating member 43. Then, the spacer member 45 and the plurality of conductor portions 15a are inserted into the slot 31 together with the foamable insulating member 43, and thereafter, the foamable insulating member 43 is foamed, and the foamable insulating member 43 is adhered to the outer peripheral surface of the annular partition wall 37 through the opening 40 of the slot 31. For this reason, the outer surfaces of the spacer member 45 and the plurality of conductor portions 15a of the coil 15 are covered with the foamable insulating member 43, and in this state, the foamable insulating member 43 is foamed within the corresponding slot 31, whereby the plurality of conductor portions 15a can be disposed at appropriate positions radially outside the slot 31. That is, the conductor portions 15a can be disposed so as to be biased radially outside within the slot 31 by the spacer member 45 disposed radially inward of the plurality of conductor portions 15a. And when the conductor portions 15a are disposed so as to be biased radially outside within the slot 31 in this way, the pressure of the coolant 23 hardly acts on the radially outer end surface of the conductor portion 15a that is most radially outer within the slot 31. As a result, it becomes difficult for the plurality of conductor portions 15a to move radially inward under the pressure of the coolant 23, and it becomes possible to prevent the partition wall main body portion 37b of the annular partition wall 37 from deforming radially inward due to the pressing by the conductor portions 15a.

[0057] Also, when the portion of the foamable insulating member 43 located radially inside the slot 31 foams, the inner surface side of the foamable insulating member 43 (the side spaced apart from the opening 40 of the slot 31) is supported by the spacer member 45. For this reason, when the foamable insulating member 43 foams, the inside of the foamable insulating member 43 is well displaced toward the opening 40 of the slot 31 while the inner surface side is supported by the spacer member 45. Therefore, when the manufacturing method of the stator 10 of the present embodiment is adopted, a part of the foamable insulating member 43 surely passes through the opening 40 of the slot 31 during foaming, and a part of it is surely adhered to the partition main body portion 37b of the annular partition 37 through the opening 40. Thus, a part of the foamable insulating member 43 can be surely adhered to the outer peripheral surface of the annular partition 37 (cover member) through the opening 40.

[0058] In particular, in the present embodiment, since the spacer member 45 having a shape in which a circular cross-section is continuous in the axial direction is adopted, when a part of the foamable insulating member 43 foams and enters the opening 40, the foaming reaction force of the foamable insulating member 43 can be efficiently supported at the top of the circular cross-section of the spacer member 45. Therefore, by adopting this configuration, a part of the foamable insulating member 43 can be more surely adhered to the outer peripheral surface of the annular partition 37 (cover member) through the opening 40.

[0059] Furthermore, in the manufacturing method of the stator 10 of the present embodiment, after the foamable insulating member 43 is foamed and the foamable insulating member 43 is adhered to the outer peripheral surface of the partition main body portion 37b of the annular partition 37 through the opening 40 of the slot 31, the spacer member 45 is extracted from the inside of the foamable insulating member 43. In the case of the manufacturing method of the present embodiment, since the rod-shaped spacer member 45 is extracted after the foamable insulating member 43 is foamed, the weight of the stator 10 can be reduced.

[0060] Also, in the manufacturing method of the present embodiment, after foaming the foamable insulating member 43, the rod-shaped spacer member 45 is removed. Therefore, a communication hole along the axial direction of the stator 10 is formed in the portion where the spacer member 45 was located inside the foamable insulating member 43. Thus, when the stator 10 is manufactured in this way, by using the communication hole portion formed inside the foamable insulating member 43 as the coolant passage 44, it becomes possible to efficiently cool the conductor portion 15a of the coil 15.

[0061] Note that the present invention is not limited to the above-described embodiment, and various design changes are possible without departing from the gist thereof. For example, in the above-described embodiment, an annular partition wall 37 that partitions between the inner peripheral surface of the stator core 14 and the outer peripheral surface of the rotor 11 is disposed as a cover member on the inner peripheral portion of the stator core 14. However, the cover member is not limited to the annular partition wall 37 that partitions between the inner peripheral surface of the stator core 14 and the outer peripheral surface of the rotor 11, and may be a cylindrical member that does not partition the space between the stator core 14 and the rotor 11 in a liquid-tight manner.

[0062] Also, in the above-described embodiment, a foamable adhesive is disposed on the outer surface of the foamable insulating member 43. However, the foamable insulating member 43 is not necessarily limited to this structure. After a part of the foamable insulating member 43 has penetrated into the opening 40 of the slot 31 by a foaming process without disposing a foamable adhesive on the outer surface of the foamable insulating member 43, a part of the foamable insulating member 43 exposed outside through the opening 40 may be adhered to the outer surface of the annular partition wall 37 (cover member) by an adhesive separately.

[0063] Furthermore, in the above-described embodiment, the slot 31 of the stator core 14 constitutes a coolant passage 44 that allows the coolant 23 in the first liquid chamber 21 to flow toward the second liquid chamber 22 side. However, the stator may have a structure in which the coolant 23 does not flow through the slot 31.

Explanation of Reference Numerals

[0064] 10... Stator 14... Stator Core 15... Coil 15a... Conductor Portion 28…Teeth 31…Slots 37…Annular partition wall (cover member) 40…Opening 43…Foamable insulating member 44…Coolant passage 45…Spacer member

Claims

1. An annular stator core having a plurality of teeth arranged in the circumferential direction and a plurality of slots formed between the adjacent teeth in the circumferential direction, A coil in which a plurality of conductor portions are wound around each of the teeth through the slots, A cylindrical cover member inserted and disposed on the inner peripheral portion of the stator core so that an outer peripheral surface thereof faces openings on the radially inner side of the plurality of slots, and A stator of a rotating electrical machine, wherein each of the slots is filled with a foaming insulating member that covers an outer surface of the plurality of conductor portions of the coil and is adhered to the outer peripheral surface of the cover member through the opening.

2. The stator of a rotating electrical machine according to claim 1, wherein the foaming insulating member has a foaming adhesive disposed on an outer surface thereof.

3. The stator of a rotating electrical machine according to claim 1 or 2, wherein the plurality of slots constitute a coolant passage through which coolant flows from one axial end side to the other end side of the stator core.

4. An annular stator core having a plurality of teeth arranged in the circumferential direction and a plurality of slots formed between the adjacent teeth in the circumferential direction, A coil in which a plurality of conductor portions are wound around each of the teeth through the slots, A method of manufacturing a stator of a rotating electrical machine, comprising a cylindrical cover member inserted and disposed on the inner peripheral portion of the stator core so that an outer peripheral surface thereof faces openings on the radially inner side of the plurality of slots, With the outer surfaces of the plurality of conductor portions of the coil covered with a foaming insulating member, the plurality of conductor portions are inserted into the slots together with the foaming insulating member, Thereafter, the foaming insulating member is foamed, and the foaming insulating member is adhered to the outer peripheral surface of the cover member through the opening of the slot.

5. A rod-shaped spacer member extending substantially along the conductor portion is disposed radially inward of the conductor portion disposed most radially inward in the slot, The outer surfaces of the spacer member and the plurality of conductor portions are covered with the foaming insulating member, The spacer member and the plurality of conductor portions are inserted into the slots together with the foaming insulating member, Thereafter, the foaming insulating member is foamed, and the foaming insulating member is adhered to the outer peripheral surface of the cover member through the opening of the slot. The method of manufacturing a stator of a rotating electrical machine according to claim 4.

6. The manufacturing method of the stator of the rotating electric machine according to claim 5, characterized in that after foaming the foaming insulation member and adhering the foaming insulation member to the outer peripheral surface of the cover member through the opening of the slot, the spacer member is removed from the inside of the foaming insulation member.

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