stator

Abstract

This invention relates to stators. It provides a technique for efficiently cooling coils disposed within slots. A stator is constructed comprising: an annular stator core having a plurality of teeth arranged circumferentially and a plurality of slots formed circumferentially between the teeth; a coil disposed within the slots; and an end cover mounted on an axial end of the stator core, the coil being fixed to the end cover, and a refrigerant flow path, i.e., a refrigerant path, being formed between the coil and the slots.

Description

Technical Field

[0001] This invention relates to a stator. Background Technology

[0002] Conventionally, it is known that stators have coils arranged in slots formed in the stator core. For example, Patent Document 1 discloses a structure in which an insulator (insulating member) is arranged around the coil arranged in the slot, thereby insulating the coil and the stator core. In addition, Patent Document 1 discloses a structure in which a clamping member is arranged at the axial end of the stator core, and the clamping member is bonded to the end of the coil using an epoxy resin.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2015-77040

[0004] The goal is to efficiently cool the coils configured within the slot. In Patent Document 1, for example, as... Figure 4 As shown, an insulator is arranged around the coil, and there is no refrigerant path for refrigerant to flow around the slot. Therefore, it is difficult to dissipate the heat of the coil efficiently. Summary of the Invention

[0005] The present invention was made in view of the above-mentioned problems, and aims to provide a technique for efficiently cooling coils disposed in slots.

[0006] One embodiment of the stator includes: an annular stator core having a plurality of teeth arranged circumferentially and a plurality of slots formed circumferentially between the teeth; a coil disposed in the slots; and an end cover mounted on the axial end of the stator core, the coil being fixed to the end cover, and a refrigerant flow path, i.e., a refrigerant path, being formed between the coil and the slots.

[0007] That is, by fixing the coil disposed in the slot to the end cover so that the coil does not move, a refrigerant flow path, i.e., a refrigerant path, is fixedly formed between the coil and the slot. According to this structure, by allowing the refrigerant to flow into the refrigerant path, the coil disposed in the slot can be cooled efficiently. Attached Figure Description

[0008] Figure 1 This is a 3D diagram of the stator.

[0009] Figure 2 This is a diagram representing the state of the stator as viewed from the direction along the central axis Ax.

[0010] Figure 3 It is Figure 2 A magnified portion of the image.

[0011] Figure 4 It means in Figure 3 The diagram shows the state after removing the end caps and inner circumferential caps.

[0012] Figure 5 It is a diagram showing the state of the aperture when observed from the direction along the axial direction.

[0013] Figure 6 yes Figure 2 AA sectional view.

[0014] Figure 7 yes Figure 2 BB cross-sectional view.

[0015] Figure 8 This is a diagram illustrating a structural example where insulating components are arranged around a coil.

[0016] Figure 9 This is a diagram illustrating a structural example where insulating components are arranged around a coil.

[0017] Figure 10 This is a diagram illustrating a structural example where insulating components are arranged around a coil.

[0018] Figure 11 This is a diagram illustrating a structure without an inner circumferential cover.

[0019] Figure 12 This is a cross-sectional view of a structural example without an inner circumferential cover.

[0020] Figure 13 This diagram illustrates a structural example in which the refrigerant orifice is not formed radially inside the terminal cover.

[0021] Figure 14 This is a cross-sectional view showing a structural example in which the refrigerant holes are not formed on the radially inner side of the terminal cover.

[0022] Figure 15 This diagram illustrates a structural example in which refrigerant holes are formed radially outward within the terminal cover.

[0023] Figure 16 This is a cross-sectional view showing a structural example in which refrigerant holes are formed radially outward within the terminal cover.

[0024] Figure 17 This is a diagram illustrating a structural example of a coil configured within a slot, close to the radially inward side.

[0025] Figure 18 This is a diagram illustrating a structural example of a coil being configured within a slot, positioned close to the radially outer side.

[0026] Explanation of reference numerals in the attached figures

[0027] 1…Stator, 10…Stator core, 11…tooth, 12…slot, 12a…refrigerant path, 12b…refrigerant path, 12c…protrusion, 12d…through section, 13…hole, 14…refrigerant path, 15…refrigerant path, 20…coil, 21…slot, 30…end cover, 31…hole, 31a…engagement section, 32…protrusion, 33…protrusion, 34…protrusion, 35…coil insertion hole, 36…refrigerant hole, 40…inner circumferential cover, 50…insulating component. Detailed Implementation

[0028] Here, embodiments of the present invention will be described in the following order.

[0029] (1) Structure of the stator:

[0030] (2) Other implementation methods, etc.:

[0031] (1) Structure of the stator:

[0032] Figure 1 This is a perspective view of the stator 1 according to this embodiment. The stator 1 includes a stator core 10, a coil 20, an end cover 30, and an inner circumferential cover 40. Furthermore, in... Figure 1 The portion of the coil 20 that is not housed in the stator core 10, i.e., the end of the coil, is shown cut off in a direction perpendicular to the axial direction.

[0033] The stator core 10 in this embodiment is a ring-shaped component. A rotor (not shown) is disposed inside the ring formed by the stator core 10. The rotor is a component that rotates about an axis Ax centered on the center of the ring formed by the stator core 10. In this specification, the direction parallel to the central axis Ax is called the axial direction, the direction perpendicular to the central axis Ax is called the radial direction, and the direction of rotation about the central axis Ax is called the circumferential direction. Furthermore, in the radial direction, the direction away from the central axis Ax is called the radial outer direction, and the direction close to the central axis Ax is called the radial inner direction.

[0034] Figure 2 This is a diagram representing the state of stator 1 as viewed from the direction along the central axis Ax. Figure 3 It is Figure 2 A portion of the enlarged image, Figure 4 It means in Figure 3 The diagram shows the state after removing the end cover 30 and the inner circumferential cover 40.

[0035] like Figure 4As shown, the stator core 10 has a plurality of teeth 11 arranged circumferentially and a plurality of slots 12 formed circumferentially between the teeth 11. In this embodiment, the teeth 11 are portions that protrude radially inward on the radially inner circumferential side of the stator core 10. The teeth 11 are formed at constant intervals circumferentially around the entire circumference of the inner circumference of the stator core 10. The number of teeth 11 can be various. In this embodiment, the cross-sectional shape of the teeth 11 in the direction perpendicular to the axial direction is the same at any position in the axial direction. Therefore, the teeth 11 are portions that protrude radially inward and extend axially with the same cross-sectional shape in the direction perpendicular to the axial direction.

[0036] The space formed circumferentially between the teeth 11 is a slot 12. Coils 20 are disposed within the slot 12. While the number of coils 20 disposed within the slot 12 arranged radially is not limited, in this embodiment it is six. Furthermore, in Figure 1 Although the coil 20 is shown cut off in a direction perpendicular to the axial direction, the coil 20 includes a housing portion disposed within the slot 12 and a coil end protruding axially from the end face of the stator core 10. Furthermore, in Figure 3 In the image, the shape of the slot 12, which is hidden by the end cap 30, is shown in dashed lines.

[0037] In this embodiment, a through portion 12d is formed in the slot 12, extending radially inward. Specifically, as... Figure 4 As shown, on the radially inner side, the inner wall of the slot 12 has a protrusion 12c extending circumferentially. The protrusion 12c is not connected in the circumferential direction and passes through the through portion 12d radially.

[0038] The end cover 30 is a component installed at the axial end of the stator core 10. In this embodiment, the end cover 30 is an annular component when viewed along the axial direction. The diameter of the inner circumference of the radially inner side of the end cover 30 is approximately the same as the diameter of the inner circumference of the radially inner side of the stator core 10. The diameter of the outer circumference of the radially outer side of the end cover 30 is smaller than the diameter of the outer circumference of the radially outer side of the stator core 10. Although the diameters of the inner and outer circumferences are not limited, it is preferable that the radial length of the end cover 30 is greater than or equal to the radial length of the slot 12. Furthermore, in this embodiment, the end cover 30 is provided at both ends in the axial direction.

[0039] In the end cover 30, a hole 31 is formed for inserting the coil 20. Figure 5The state of the hole 31 as viewed from the axial direction is shown. The simplified shape of the hole 31 is a rectangle that is longer in the radial direction. The longer side of the rectangle is greater than the sum of the radial lengths of the coil 20 disposed in the slot 21. The shorter side of the rectangle is approximately the same as the circumferential length of the coil 20 disposed in the slot 21. Therefore, if the coil 20 is inserted into the hole 31, the coil 20 will not move circumferentially.

[0040] In this embodiment, the hole 31 has a plurality of circumferentially extending protrusions 32, 33, and 34 formed along its long side in the radial direction. Protrusion 32 is located on the outermost side in the radial direction, and protrusion 34 is located on the innermost side in the radial direction. Protrusion 33 is located in the radial direction between protrusions 32 and 34.

[0041] Each of the protrusions 32, 33, and 34 protrudes circumferentially toward the inside of the hole 31 from each of the two long sides of the hole 31. Furthermore, the two protrusions formed on the two long sides, which are circumferentially opposite each other, are formed at the same position radially. Also, the radial distance between adjacent protrusions of each of the protrusions 32, 33, and 34 is approximately the same as the radial distance of the coil 20.

[0042] Therefore, the coil 20 can be arranged radially between adjacent protrusions 32, 33, and 34. The hole formed between the radially adjacent protrusions 32, 33, and 34 is called the coil insertion hole 35. Figures 1-3 The image shows the state in which the coil 20 is positioned in the coil insertion hole 35.

[0043] With the coil 20 inserted into the coil insertion hole 35 and the end cover 30 in contact with the axial end of the stator core 10, each coil 20 is fixed to the end cover 30. The method of fixing the coil 20 is not limited, but in this embodiment, the coil 20 and the end cover 30 are fixed by adhesive bonding. According to this structure, the coil 20 and the end cover 30 can be fixed using a simple method. The adhesive is not limited as long as it can fix the coil 20 and the end cover 30. For example, epoxy resin can be used.

[0044] In this embodiment, the plurality of coils 20 disposed in the slot 12 are enclosed within the slot 12 in a plane perpendicular to the axial direction. That is, in the direction perpendicular to the axial direction, the entire cross-section of the plurality of coils 20 exists inside the line forming the outer periphery of the cross-section of the slot 12. In this embodiment, as... Figure 3 As shown, the radial length of the hole 31 in the end cover 30 is approximately the same as the radial length of the slot 12. On the other hand, the circumferential length of the hole 31 in the end cover 30 is shorter than the circumferential length of the slot 12, and the hole 31 is located at the center of the slot 12 in the circumferential direction. Therefore, by fixing the coil 20 to the end cover 30, as... Figure 4As shown, a gap is formed on both sides of the coil 20, between the coil 20 and the inner wall of the slot 12. This gap becomes the refrigerant flow path, namely refrigerant path 12a.

[0045] In this embodiment, the coil 20 is separated from both the radially outer and radially inner sides of the hole 31 and is fixed. That is, the coil 20 is fixed in a state close to the radial center of the hole 31. Therefore, by fixing the coil 20 to the end cover 30, on both radial sides of the coil 20, as... Figure 4 As shown, a gap is formed between the coil 20 and the inner wall of the slot 12. This gap becomes the refrigerant flow path, namely refrigerant path 12b. Figure 6 yes Figure 2 AA sectional view. For example... Figure 6 As shown, refrigerant paths 12b are formed on the radial inner and radial outer sides of coil 20, extending axially.

[0046] Refrigerant paths 12a and 12b are spaces that serve as flow paths for the refrigerant. Therefore, in this embodiment, an inner circumferential cover 40 is provided to allow the refrigerant to flow within these refrigerant paths 12a and 12b. The inner circumferential cover 40 is a cylindrical component, and its axial length is approximately the same as the axial length of the stator core 10. The diameter of the outer circumferential surface of the inner circumferential cover 40 is approximately the same as the diameter of the inner circumferential surface of the stator core 10. Figure 1 , Figure 2 , Figure 3 , Figure 6 As shown, the inner circumferential cover 40 is used to embed into the radially inner side of the stator core 10. The inner circumferential cover 40 is a plate-shaped component that exists throughout the entire inner circumference of the stator core 10, thus blocking the through portion 12d of the slot 12. As a result, it is possible to prevent the refrigerant flowing in the refrigerant passages 12a and 12b from leaking radially inward through the through portion 12d.

[0047] As described above, in this embodiment, refrigerant paths 12a and 12b are formed covering the entire circumference of coil 20 in a plane perpendicular to the axial direction. Refrigerant is supplied to the refrigerant paths 12a and 12b formed in each slot 12 by various methods. Figure 6 In the example shown, a radially extending hole 13 is formed at the axial center of the stator core 10. The hole 13 extends from the radial outer periphery of the stator core 10 to the inner wall of the radial outer side of the slot 12. If refrigerant is supplied to the hole 13 from the outside of the stator core 10, refrigerant is supplied to the slot 12.

[0048] Therefore, the opening of hole 13 in the inner wall of slot 12 becomes a supply port for supplying refrigerant to slot 12. When refrigerant is supplied from this supply port, it passes through refrigerant paths 12a and 12b and moves towards the axial end, being discharged from hole 31, which serves as a refrigerant discharge port. According to the above structure, by supplying refrigerant to slot 12 from the axial center, the refrigerant flows towards both ends in the axial direction, cooling coil 20 and stator core 10 is achieved. According to this structure, compared to a structure where refrigerant is supplied to slot 12 from one axial end and discharged from the other end, the pressure required for refrigerant flow can be reduced.

[0049] Furthermore, the structure for supplying refrigerant to each of the multiple slots 12 located circumferentially can employ various structures. Figure 6 In the example shown, a refrigerant passage 14 covering the entire circumference is connected to the hole 13, and a refrigerant passage 15 extending radially from the refrigerant passage 14 and connecting to each slot 12 is formed. According to this structure, refrigerant can flow circumferentially from the hole 13 through the refrigerant passage 14, and refrigerant can flow through the refrigerant passage 15 to each slot 12. Furthermore, the hole 13, refrigerant passage 14, and refrigerant passage 15 are located at the axial center of the stator core 10, but are not limited to a structure strictly located at the center axially. That is, the hole 13, refrigerant passage 14, and refrigerant passage 15 may also be formed at a position off-center axially.

[0050] According to the above structure, the refrigerant supplied from the outside of the stator core 10 to the inside of the stator core 10 and reaching the slot 12 flows axially along the coil 20 within the refrigerant paths 12a and 12b. The refrigerant is in direct contact with the coil 20, thus efficiently cooling the coil 20 disposed within the slot. Furthermore, in this embodiment, the coil 20 is fixed by the end cover 30, forming refrigerant paths 12a and 12b that cover the entire circumference of the coil 20 between the coil 20 and the slot 12, so the coil 20 does not contact the slot 12. Therefore, even without omitting the sheet-like insulating component, insulation between the coil 20 and the slot 12 is possible.

[0051] As described above, in this embodiment, the position of the coil 20 is fixed in the slot 12 by fixing the long side of the hole 31 to both sides of the coil 20 in the circumferential direction. In this embodiment, a structure for easily achieving this fixation is formed in the end cover 30. Specifically, the end cover 30 has an engaging portion 31a that extends axially toward the stator core 10 and engages with the slot 12.

[0052] Figure 7 yes Figure 2 BB sectional view. For example... Figure 7As shown, the end cover 30 has a plate-shaped portion, namely the engaging portion 31a, extending axially toward the stator core 10 from the long side portion of the hole 31. The axial length L1 of the engaging portion 31a is set to the length of the axial end of the engaging portion 31a that is inserted into the slot 12. In this embodiment, it is the same length as the radial length L2 of the hole 31. Furthermore, the length of the engaging portion 31a is not limited as long as it is set to the length of the axial end of the slot 12. In short, the engaging portion 31a can easily position the end cover 30 by inserting the engaging portion 31a into the axial end of the slot 12.

[0053] The radial length of the engaging portion 31a is approximately the same as the radial length of the portion where the multiple coils 20 are arranged (see reference). Figure 3 Therefore, in the radial direction, the engaging portion 31a is in contact with each coil 20 at both ends of its respective circumference. In the above structure, the area of ​​the portion of the end cover 30 in contact with the coil 20 is larger at both ends of the circumference than in the case where the engaging portion 31a is not present. Therefore, the coil 20 and the end cover 30 can be easily bonded together.

[0054] As described above, in this embodiment, protrusions 32, 33, and 34 are formed in the hole 31 of the end cover 30. Protrusion 33 is located between radially adjacent coils 20. If... Figure 5 In the example shown, there are six radially adjacent coils 20, so there are five boundaries for each coil, and the protrusion 33 is inserted into each boundary. If the protrusion 33 is positioned between adjacent coils 20, the adjacent coils 20 are radially separated from each other by the radial width of the protrusion 33. Therefore, in this embodiment with the protrusion 33, a gap is created between the radially adjacent coils 20, allowing refrigerant to flow between them. Thus, the coils 20 can be cooled more efficiently. The circumferential length and radial length of the protrusion 33 are not limited, as long as they are set such that refrigerant can flow into the space created by separating the adjacent coils 20. Furthermore, in this embodiment, the protrusion 33 is not connected circumferentially, so a hole is formed at the location where it is held. Refrigerant can be discharged through this hole.

[0055] The protrusion 32 is formed at a position that contacts the radially outer surface of the outermost coil. In this embodiment, the hole 31 extends radially outward more than the protrusion 32. Therefore, according to the protrusion 32, the radially outermost coil 20 can be positioned so that it will not move radially outward within the hole 31. According to this structure, the hole can be formed radially outward more than the protrusion 32.

[0056] The protrusion 34 is formed at a position that contacts the radially inner surface of the innermost coil. In this embodiment, the hole 31 extends radially inward more than the protrusion 34. Therefore, according to the protrusion 34, the radially innermost coil 20 can be positioned so that it will not move radially inward within the hole 31. According to this structure, the hole is formed radially inward more than the protrusion 34.

[0057] Since the holes located radially outward of the protrusion 32 and radially inward of the protrusion 34 exist as through holes in the end cover 30, they become refrigerant holes 36 through which the refrigerant passes. With the refrigerant holes 36 formed in this way, the refrigerant flowing within the slot 12 and exiting from the opening at the axial end of the slot 12 also passes through the refrigerant holes 36 of the end cover 30 and is discharged to the outside of the stator core 10. Therefore, compared to a structure without refrigerant holes 36, the refrigerant can circulate more efficiently.

[0058] (2) Other implementation methods, etc.:

[0059] The above-described embodiment is an example of implementing the present invention, and various other embodiments are also possible. For example, the slot 12 and the coil 20 can be insulated by an insulating component. Figure 8 From and Figure 4 The view from the same direction shows the structure in which an insulating component 50 is arranged around the coil 20. Figure 8 In the structure shown, the structure other than the insulating component 50 is the same as in the embodiment described above. Figure 8 In this embodiment, the same structural elements as described above are indicated by the same reference numerals. Thus, by using the insulating component 50, insulation between the coil 20 and the slot 12 can be more reliably achieved. The type of insulating component is not limited to... Figure 8 As shown. For example, as Figure 9 As shown, it can also be a structure where the insulating paper 510 is wound around the coil 20, such as... Figure 10 As shown, the insulating paper 511 can also be arranged in a manner that runs along the inner wall of the slot 12.

[0060] Alternatively, a structure can be adopted in which a refrigerant path is formed within the slot 12 without the inner circumferential cover 40. Figure 11 From and Figure 4 The view from the same direction shows an example of a structure without the inner circumferential cover 40. Figure 12 With Figure 6 The same sectional view is shown. Figure 11 , Figure 12In the example shown, no through portion 12d is formed in the stator core 10 on the radially inner side of the slot 12, but an inner wall 120c without penetration is formed throughout the entire circumference. According to this structure, the refrigerant can flow inside the refrigerant passages 12a and 12b without using the inner circumferential cover 40.

[0061] Furthermore, the shape of the hole 31 is not limited to the shape described in the above embodiment. For example, the refrigerant hole 36 may also be formed on either the radially outer or radially inner side. Figure 13 From and Figure 3 In the end cover 30, viewed from the same direction, there is no example of a structure where the refrigerant hole 36 is formed on the radially outer side but on the radially inner side. Figure 14 With Figure 6 The same sectional view is shown. Figure 13 , Figure 14 In this embodiment, the same structural reference numerals as those in the above embodiment are used. In this structure, the hole 310 is shorter radially than the hole 31. In the refrigerant path 12b, there is no refrigerant hole 36 on the axial extension line of the refrigerant path 12b on the radially inner side. The refrigerant hole 36 is present on the axial extension line of the refrigerant path 12b on the radially outer side. Therefore, the refrigerant passing through the refrigerant paths 12a and 12b and reaching the axial end is discharged from the refrigerant hole 36 on the radially outer side.

[0062] Figure 15 With Figure 3 The state viewed from the same direction shows an example in the end cover 30 where the refrigerant hole 36 is formed on the radially inner side instead of the radially outer side. Figure 16 With Figure 6 The same sectional view is shown. Figure 15 , Figure 16 In this embodiment, the same structural reference numerals as those in the above embodiment are used. In this structure, the hole 311 is shorter in the radial direction than the hole 31. In the refrigerant path 12b, there is no refrigerant hole 36 on the axial extension line of the refrigerant path 12b on the radially outer side. The refrigerant hole 36 is present on the axial extension line of the refrigerant path 12b on the radially inner side. Therefore, the refrigerant passing through the refrigerant paths 12a and 12b and reaching the axial end is discharged from the refrigerant hole 36 on the radially inner side.

[0063] according to Figure 13 , Figure 14 , Figure 15 , Figure 16 The structure shown allows for the fixation of both circumferential sides and one radial side of the coil 20 via the end cap 30, thus enabling more reliable positioning of the coil 20 within the slot 12. Of course, in Figure 13 , Figure 14 , Figure 15 , Figure 16 In the example shown, the through portion 12d on the radially inner side of the slot 12 can also be closed, and the inner circumferential cover 40 is omitted.

[0064] Furthermore, the refrigerant path formed by fixing the coil 20 to the end cover 30 can also be formed at any position in the radial or circumferential direction of the coil 20. For example, in a structure in which the circumferential surface of the coil 20 is fixed to the end cover 30, since the contact surface between the coil 20 and the end cover 30 is closed in the circumferential direction, it is also possible to configure a structure in which the refrigerant path is formed on at least one of the radial inner and radial outer sides of the coil 20 and discharged from the hole in the end cover 30.

[0065] For example, such as Figure 13 , Figure 14 As shown, although a refrigerant hole 36 is formed on the radially outer side in the end cover 30, in a structure where a refrigerant hole 36 is not formed on the radially inner side, it may also be a structure where a refrigerant path 12b is not formed on the radially inner side. Figure 17 Therefore, from and Figure 4 The diagram showing the state viewed from the same direction illustrates an example of a structure in which the coil 20 is arranged within the slot 120 in a state closer to the radial inward side.

[0066] In this example, it has the ability to insert Figure 17 The coil insertion hole 35 of the coil 20 and the refrigerant hole 36 located on the radially outer side are formed in the end cover 30. In this structure, refrigerant paths 12a are formed at both circumferential ends of the coil 20, and refrigerant paths 12b are formed on the radially outer side. The refrigerant passing through the refrigerant paths 12a and 12b passes through the refrigerant hole 36 of the end cover 30 and is discharged. Furthermore, in this structure, it is preferable to arrange an insulating member 51 between the coil 20 on the radially inner side and the inner wall of the slot 12.

[0067] Figure 18 Therefore, from and Figure 4 The diagram, viewed from the same direction, shows an example of a structure in which a coil 20 is arranged within slot 121, near the radially outer side. In this example, it has the capability to insert... Figure 18 The coil insertion hole 35 of the coil 20 and the refrigerant hole 36 located on the radially inner side are formed in the end cover 30. In this structure, refrigerant passages 12a are formed at both circumferential ends of the coil 20, and refrigerant passages 12b are formed on the radially inner side. The refrigerant passing through the refrigerant passages 12a and 12b passes through the refrigerant hole 36 of the end cover 30 and is discharged.

[0068] Furthermore, in this structure, it is preferable to arrange an insulating member 52 between the radially outer coil 20 and the inner wall of the slot 12. Refrigerant supply to the slot 12 can also be implemented in various ways. For example, a refrigerant supply port can be provided radially outer, at a position avoiding the radially outer surface of the coil 20. Figure 18 In the structure shown, the coil 20, which is prone to heat accumulation and exists on the radially inner side, can be cooled by the refrigerant passing through the refrigerant path 12a, so that cooling can be performed efficiently.

[0069] A stator core is simply a ring-shaped component having multiple teeth arranged circumferentially and multiple slots formed between the teeth circumferentially. That is, the stator core only needs to have multiple slots formed by multiple teeth, with a coil disposed in each slot. Furthermore, it only needs to be configured such that the interaction between the magnetic field formed by the coil and the magnetic field formed by the rotor allows the rotor to rotate relative to the stator. The number of magnetic poles, the number of slots, and the material of the stator core can also have various structures.

[0070] The stator core as a whole only needs to be ring-shaped. The shapes of the radially inner and radially outer faces of the ring formed by the stator core are not limited. For example, the radially outer face can be circular or polygonal when viewed from the axial direction. Teeth are formed on the radially inner face, and slots are formed between the teeth. In the stator core, the approximate shape including the teeth can be considered ring-shaped, and the portion excluding the teeth can be considered ring-shaped.

[0071] The coil simply needs to be placed within the slot. The shape of the coil and the method of placement are not limited. Therefore, the coil can be wound around teeth, or segmented coils can be inserted axially and engaged at the axial ends. The coil includes at least a housing portion housed in the slot and a coil end protruding axially from the end face of the stator core. The housing portion is the part housed in the slot, typically within the slot, and is the portion held between the two end faces of the axially extending stator core. A refrigerant path is formed by fixing the coil to the end cover in a manner that creates a fixed gap between the housing portion and the inner wall of the slot. The coil end is the portion protruding axially from the end face of the stator core; that is, the coil present on the opposite side of the slot with reference to the end face of the stator core is the coil end.

[0072] An end cover is any component that is installed on the axial end of the stator core. The end cover is a component installed for the protection and insulation of the axial end of the stator core. The end cover only needs to exist at the axial end of the stator core to protect at least a portion of the part other than the coil end; its shape and size are not limited.

[0073] A refrigerant path is simply a space formed between the coil and the slot that allows refrigerant to flow. That is, it only needs to be formed in a way that allows refrigerant to flow axially. The refrigerant path is simply a space fixedly formed by configuring the coil to be fixed to the end cover and not moving relative to the slot. Therefore, the cross-section of the slot in the direction perpendicular to the axial direction is larger than the cross-section of the coil disposed within the slot. The shape of the slot and the shape of the coil are not limited, and the location of the refrigerant path is also unrestricted. Therefore, it is not limited to a structure formed throughout the entire circumference of the coil. A refrigerant path can be formed along one surface in the radial and circumferential directions of the coil, or it can be formed along multiple surfaces.

Claims

1. A stator, characterized in that, have: The annular stator core has a plurality of teeth arranged circumferentially and a plurality of slots formed circumferentially between the teeth. The coil, which is disposed within the aforementioned slot; and End caps, which are installed at the axial ends of the aforementioned stator core. The coil is fixed to the end cover, and a refrigerant flow path, i.e., a refrigerant path, is formed between the coil and the slot.

2. The stator according to claim 1, characterized in that, The end cap has a coil insertion hole for inserting the coil and a refrigerant hole for passing through the refrigerant.

3. The stator according to claim 1 or 2, characterized in that, The aforementioned refrigerant path is formed on at least one of the radial inner and radial outer sides of the aforementioned coil. The circumferential surface of the coil is fixed to the end cover.

4. The stator according to claim 1 or 2, characterized in that, The aforementioned refrigerant path is formed by covering the entire circumference of the aforementioned coil in a plane perpendicular to the axial direction.

5. The stator according to claim 1 or 2, characterized in that, The aforementioned coil and the aforementioned end cover are fixed together by adhesive.

6. The stator according to claim 1 or 2, characterized in that, The aforementioned end cover has a engaging portion that extends axially toward the stator core and engages with the aforementioned slot.

7. The stator according to claim 1 or 2, characterized in that, In each of the aforementioned slots, a refrigerant supply port is formed at the central portion in the axial direction, and the openings at both ends of the refrigerant path in the axial direction are outlets for the refrigerant supplied from the aforementioned supply port.

8. The stator according to claim 1 or 2, characterized in that, The slot and the coil are insulated from each other by an insulating component.

9. The stator according to claim 1 or 2, characterized in that, The aforementioned slot has a through portion extending radially inward. It also has a cylindrical inner circumferential cover that contacts the radially inner side of the stator core and blocks the through portion.

10. The stator according to claim 1 or 2, characterized in that, The aforementioned end cover has a protrusion located between the aforementioned coils that are adjacent to each other in the radial direction.

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