Stator

Abstract

The present invention provides a stator including a cylindrical stator core formed with a plurality of first slots (slots), and a coil fitted on the stator core by being inserted into the plurality of first slots, an inner wall portion of the first slot includes a pair of side wall portions extending radially outward from an inner peripheral portion of the stator core and facing each other in a circumferential direction, and a bottom wall portion connected to each end portion of the side wall portions such that the first slot opens radially inward. An outer coil disposed on the outermost side in the radial direction among the coils in the first slots is disposed at a distance from the bottom wall portion in the radial direction such that a space portion is formed between the outer coil and the bottom wall portion, and the space portion constitutes an in-core flow path through which a refrigerant flows.

Description

Technical Field

[0001] The present invention relates to a motor, in particular to a stator of a permanent magnet motor. Background Art

[0002] With the popularity of electric vehicles in recent years, from the perspectives of electric vehicle motor installation, vehicle model expansion, production, cost reduction, etc., there is a demand for miniaturization of motors. In order to miniaturize the motor without reducing the motor output, it is necessary to increase the output density of the motor, and more specifically, it is necessary to increase the current density of the current flowing through the coil. However, if the current density is increased, the heat generated by the coil increases, so the technology for cooling the coil and its surrounding parts (for example, the inside of the stator core) becomes the key. JP2022-182069A discloses a technology in which a metal pipe for the flow of refrigerant is provided inside the narrow slots of the stator core to cool the stator core and the coil.

[0003] In the technology disclosed in JP2022-182069A, a process of installing pipes inside the narrow slots is required, so the manufacturing process of the stator may become complicated. In addition, since the refrigerant indirectly cools the stator core and coils through the pipes, there is room for improvement in effectively cooling the stator core and coils. Summary of the Invention

[0004] The present invention has been made in view of the above, and an object thereof is to provide a stator that can be manufactured more simply and that can effectively cool the stator core and coil.

[0005] In order to achieve the above-mentioned purpose, the stator described in the present invention is constructed as follows. The stator described in the present invention includes: a cylindrical stator core, which is formed with a plurality of slots extending axially therethrough; and a coil, which is assembled on the stator core by being inserted into the plurality of slots. The inner wall portion of the slot includes a pair of side wall portions extending radially outward from the inner peripheral portion of the stator core and circumferentially opposite to each other, and a bottom wall portion connected to each end of the pair of side wall portions, so that the slot opens radially inward. Among the coils in the slot, the outer coil arranged at the radially outermost side is radially spaced apart from the bottom wall portion, so that a space portion is formed between the outer coil and the bottom wall portion, and the space portion constitutes an in-core flow path for the flow of refrigerant.

[0006] According to the above configuration, the inner wall portion of the slot includes a pair of sidewall portions extending radially outward from the inner circumference of the stator core and opposing each other in the circumferential direction, and a bottom wall portion connected to each end of the pair of sidewall portions. The slot is open radially inward, thereby providing an opening portion on the radially inner side of the slot, and providing a closed portion on the radially outer side of the slot, which is closed by the pair of sidewall portions and the bottom wall portion. Such a closed portion is provided in the slot, and an outer coil positioned radially outermost among the coils in the slot is radially spaced from the bottom wall portion, forming a space between the outer coil and the bottom wall portion. The space is thus defined by the closed portion (the pair of sidewall portions and the bottom wall portion) and the radially outer side of the outer coil.

[0007] The space separated as described above constitutes an intra-core flow path for the refrigerant, thereby enabling the intra-core flow path to be provided within the stator core without installing other components (e.g., pipes) within the slots. This facilitates the manufacture of a stator having a stator core with the intra-core flow path formed therein.

[0008] Furthermore, the refrigerant flowing through the core flow path (space) forms an inner core flow path through the space. The refrigerant contacts the stator core at the enclosed portion separating the space, and similarly contacts the coil radially outward of the outer coil separating the space, thereby directly cooling both the stator core and the coil. This effectively cools the stator core and coil. This allows for a stator that can be manufactured more simply and effectively cools the stator core and coil.

[0009] In the stator, the pair of sidewalls may be provided with first protrusions configured to prevent the outer coil from moving radially outward. This prevents the outer coil from shifting radially outward and intruding into the space, thereby maintaining the flow path volume within the core.

[0010] In the stator, the pair of sidewalls may be provided with second protrusions configured to prevent radially inward movement of the inner coil, which is positioned radially innermost among the coils in the slot. This prevents the inner coil from shifting radially inward and thus escaping from the slot, thereby reliably retaining the coil within the slot.

[0011] In the above-mentioned stator, an annular guide component coaxially arranged with the stator core can be provided on at least one axial end side of the stator core, and the guide component is provided with: an inlet portion for introducing refrigerant supplied from the outside; and a core connection portion, which is in communication with the inlet portion and connected to the inlet of the core inner flow path. According to this structure, at least a portion of the refrigerant supplied from the outside flows directly from the core connection portion into the core inner flow path of the stator core after being introduced by the inlet portion of the guide component. Therefore, at least a portion of the refrigerant supplied from the outside is provided to the core inner flow path in a fresh state without taking heat from other components of the stator. As a result, the stator core and the coil can be cooled more effectively.

[0012] As described above, according to the present invention, a stator can be provided which can be manufactured more simply and can effectively cool the stator core and coil. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic longitudinal sectional view showing a part of the motor unit in the first embodiment. Figure 2 This is a perspective view of the stator in the first embodiment. Figure 3 yes Figure 2 Exploded perspective view of the stator. Figure 4 It is a front schematic diagram showing a part of the stator core in the embodiment. Figure 5 This is a schematic front view showing a portion of an oil guide in the first embodiment. Figure 6 It is a diagram for explaining the first flow pattern. Figure 7 It is a diagram for explaining the oil flow in the front oil deflector and the stator core in the first flow pattern. Figure 8 This is a schematic front view showing a portion of a stator core in a modified example of the first embodiment. DETAILED DESCRIPTION

[0014] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. (Implementation 1) (Structure of the motor unit) Figure 1 1 is a schematic longitudinal section diagram showing a portion of the motor unit A in the first embodiment. Figure 1 In the figure, one axial end side of the motor unit A is shown, and the other axial end side is also shown. First, the structure of the motor unit A in the embodiment 1 of the present invention is described. Figure 1As shown, the motor unit A includes a motor 1 and a housing 9 .

[0015] The motor 1 is, for example, an interior permanent magnet motor (IPM motor) used as a driving source for electric vehicles. The motor 1 includes a shaft 10 serving as a rotating shaft, a cylindrical rotor 11 in which the shaft 10 is fixed in a central hole, and a cylindrical stator 12. The stator 12 is radially spaced apart from the rotor 11 so that the inner circumference of the stator 12 faces the outer circumference of the rotor 11. The shaft 10 is configured to be integral with the rotor 11 and to rotate relative to the stator 12. The shaft 10, the rotor 11, and the stator 12 are concentrically arranged, and in the figure, these axial directions are uniformly represented by the symbol δ. The structure of the stator 12 will be described in detail later.

[0016] Oil is supplied as a refrigerant to the motor 1. More specifically, the oil stored in an oil pan (not shown) is cooled by a heat exchanger (not shown) and then pressure-fed to the motor 1 by an oil pump OP. Figure 1 The thick dashed arrows in the figure schematically show the flow of oil, and the same applies to the thick arrows and thick dashed arrows in the following figure. After the power supply machine 1 cools down, the oil is stored in the oil pan again.

[0017] The housing 9 houses the rotor 11 and stator 12, while exposing both ends of the shaft 10. A flow path 90 is formed within the housing 9 for externally supplied oil to flow through the motor 1. Although not shown, other oil flow paths may be formed within the housing 9, such as those for flowing oil through other components (such as bearings). The structure of the housing 9 will be described in detail later.

[0018] (Stator Structure) Figure 2 1 is a perspective view of the stator 12 in the first embodiment. Next, the structure of the stator 12 in the first embodiment of the present invention will be described in detail. Figure 2 As shown, the stator 12 includes a stator core 2, an oil deflector 3 (a guide component), a coil 4 formed of rectangular wire (SC) (segment conductor) windings, and a secondary oil deflector 5 (a secondary guide component). The stator 12 is configured so that current flows from a power supply (not shown) through input terminal B through the coil 4, making the coil 4 the primary heat source of the stator 12. Therefore, the stator 12 is configured so that the coil 4 is cooled primarily by oil flowing in through the flow path 90 of the housing 9. The following describes the various components of the stator 12 in detail, followed by an explanation of the oil flow pattern.

[0019] <Parts of the stator> Figure 3 yes Figure 2 The stator 12 is an exploded perspective view. Figure 3 In the figure, the coil 4 is omitted for the sake of convenience. Figure 4 : is a front view schematic diagram showing a portion of the stator core 2 in the embodiment. Figure 3 As shown, the stator core 2 is cylindrical and is made of magnetic materials such as electromagnetic steel. Figure 3 and Figure 4 As shown, a plurality of first teeth 21 are formed on the stator core 2, each extending circumferentially inward and arranged circumferentially, and the plurality of first teeth 21 are formed along the entire axial length of the stator core 2. The space between the adjacent plurality of first teeth 21 becomes a first slot 20 (slot). Therefore, a plurality of first slots 20 are formed on the stator core 2, each penetrating axially and arranged circumferentially. Each first slot 20 extends radially outward from the inner peripheral portion 2s of the stator core 2, so that the first slot 20 opens radially inward. In the plurality of first slots 20, the coil 4 described in detail later is inserted, as shown in FIG. Figure 4 As shown, the coils 4 are arranged in a row along the radial direction in the first slot 20 .

[0020] like Figure 4 As shown, the inner wall portion 200 of the first slot 20 includes a pair of circumferentially opposed sidewall portions 201 and 202 extending radially outward from the inner circumference 2s of the stator core 2, and a bottom wall portion 203 connected to the ends of the pair of sidewall portions 201 and 202, so that the first slot 20 is open radially inward. Thus, an opening portion P1 is provided radially inwardly of the first slot 20, and a closed portion P2 is provided radially outwardly of the first slot 20, which is closed by the sidewall portions 201 and 202 and the bottom wall portion 203.

[0021] Likewise Figure 4 As shown, the outer coil 4a, which is positioned radially outermost among the coils 4 within the first slot 20, is radially spaced apart from the bottom wall 203 (e.g., d = approximately 2 mm), so that a space α is formed between the outer coil 4a and the bottom wall 203. With the enclosed portion P2 provided in the slot and the outer coil 4a positioned as described above, the space α is partitioned by the enclosed portion P2 and the radially outer portion 41 of the outer coil 4a.

[0022] The space α separated as described above constitutes the in-core flow path 22 through which the oil flows. More specifically, the in-core flow path 22 is formed by the space α itself, which is formed radially outside the outer coil 4a by isolating the internal space of the first slot 20 with the outer coil 4a. No other components (such as pipes) forming an oil flow path are provided within the first slot 20. Since the space α constitutes the in-core flow path 22 through which the oil flows, the in-core flow path 22 can be provided within the stator core 2 without installing other components within the first slot 20. This makes it easier to manufacture the stator 12 including the stator core 2 having the in-core flow path 22 formed therein.

[0023] Furthermore, if other components are installed inside the first slots 20 when the oil flow path is formed inside the stator core 2, the inner wall 200 of the first slot 20 may be damaged during installation, and this damage may further reduce the strength of the stator core 2. In this regard, the stator core 2 having the in-core flow path 22 formed in the space α as described above can avoid such damage and strength reduction. Therefore, the stator 12 including the stator core 2 having the in-core flow path 22 formed therein can be manufactured without affecting the strength of the stator core 2.

[0024] Furthermore, the aforementioned space α forms an in-core flow path 22. Oil flowing through the in-core flow path 22 (space α) contacts the stator core 2 at the enclosed portion P2 that separates the space α. It also contacts the coil 4 at the radially outer portion 41 of the outer coil 4a that separates the space α, thereby directly cooling both the stator core 2 and the coil 4. More specifically, the stator 12 is configured such that oil flowing through the in-core flow path 22 (space α) directly cools both the stator core 2 and the coil 4. Thus, the in-core flow path 22 formed by the space α effectively cools the stator core 2 and the coil 4.

[0025] like Figure 3 As shown, the core flow path 22 includes an inner core flow path 22F for flowing oil axially forward, and an inner core flow path 22R for flowing oil axially rearward. The inner core flow paths 22F and 22R are provided inside the first slits 20 in every two consecutive first slits 20, so that the inner core flow paths 22F and 22R are alternately arranged in pairs in the circumferential direction (two inner core flow paths 22F and two inner core flow paths 22R are alternately arranged). Below, for ease of description, matters common to the inner core flow paths 22F and 22R are sometimes described using the common reference numeral 22.

[0026] In addition to the above structures, Figure 4As shown, first protrusions 204 and 205 are provided on the sidewalls 201 and 202. These first protrusions 204 and 205 are configured to prevent radially outward movement of the outer coil 4a. The first protrusions 204 and 205 are positioned radially outward relative to the outer coil 4a and project from the sidewalls 201 and 202 toward the interior of the first slot 20, such that the first protrusions 204 and 205 face each other in the circumferential direction. These first protrusions 204 and 205 prevent the outer coil 4a from shifting radially outward and intruding into the space α, thereby maintaining the flow path volume of the in-core flow path 22.

[0027] Furthermore, in addition to the first protrusions 204 and 205, as shown in FIG. Figure 4 As shown, second protrusions 206 and 207 are further provided on the sidewalls 201 and 202. These second protrusions 206 and 207 are configured to prevent radial inward movement of the inner coil 4b, which is positioned radially innermost among the coils 4 within the first slot 20. The second protrusions 206 and 207 are positioned radially inward relative to the inner coil 4b and project from the sidewalls 201 and 202 toward the interior of the first slot 20, such that the second protrusions 206 and 207 face each other in the circumferential direction. These second protrusions 206 and 207 prevent the inner coil 4b from shifting radially inward and escaping from the first slot 20, thereby reliably retaining the coil 4 within the slot.

[0028] like Figure 2 and Figure 3 As shown, the oil guides 3 are arranged at both axial ends of the stator core 2. They include an oil guide 3F arranged at one axial end, or the front side, of the stator core 2, and an oil guide 3R arranged at the other axial end, or the rear side, of the stator core 2. Both oil guides 3F and 3R are annular, having approximately the same outer and inner diameters as the stator core 2, and are arranged coaxially with the stator core 2. The two oil guides 3F and 3R are connected via an in-core flow path 22, allowing oil to flow from one oil guide to the other through the in-core flow path 22 of the stator core 2.

[0029] The oil guides 3F and 3R are arranged in opposite directions and have the same shape. Therefore, for convenience of description, the common items of the oil guides 3F and 3R are sometimes described using the common reference numeral 3.

[0030] The oil guide 3 is formed of a non-magnetic material, more specifically, a resin material (for example, SPS: syndiotactic polystyrene, PPS: polyphenylene sulfide). Figure 3As shown, the oil guide 3 is formed with a plurality of second teeth 31 along its entire axial length. These second teeth 31 correspond to the plurality of first teeth 21 of the stator core 2, extend circumferentially inward, and are arranged circumferentially. The spaces between adjacent second teeth 31 form second slots 30. Thus, the oil guide 3 is formed with a plurality of second slots 30 extending axially through it, corresponding to the plurality of first slots 20. Each second slot 30 extends radially outward from the inner circumference 3s of the oil guide 3, opening radially inward.

[0031] Figure 5 1 is a front view schematic diagram showing a portion of the oil guide 3 in the first embodiment. Figure 5 As shown, the oil guide 3 is provided with a chamber 32 as an internal space, and an inlet portion 33 for introducing oil supplied from the outside. In addition, a plurality of ejection portions 34, a plurality of first connection portions 35 (core connection portions), a plurality of second connection portions 36, and a plurality of auxiliary ejection portions 37 are provided. Each ejection portion 34 is connected to the inlet portion 33 via the chamber 32, and is configured to eject oil toward the coil end 40. Each first connection portion 35 is connected to the inlet portion 33 via the chamber 32, and is connected to the inlet port of the inner core flow path 22 in the stator core 2. On the other hand, each second connection portion 36 is connected to the outlet port of the inner core flow path 22. Each auxiliary ejection portion 37 is connected to the second connection portion 36, and is configured to eject oil flowing in from other oil guides 3 toward the coil end 40. As shown Figure 5 As shown, the ejection portion 34 and the auxiliary ejection portion 37 are holes opening toward the axial outside and are provided at the axial outside portion of the oil guide 3. In contrast, the first connection portion 35 and the second connection portion 36 are holes opening toward the axial inside and are provided at the axial inside portion of the oil guide 3.

[0032] like Figure 5 As shown, the chamber 32 includes a concentric annular portion 320, which is arranged to surround the second slot 30 from the radial outside, and a plurality of branch portions 321, which branch radially inward from the annular portion 320 toward the interior of the second tooth 31. Each branch portion 321 is connected to the ejection portion 34 or the first connecting portion 35. The terminal portion 322, which serves as the radially inner end of the branch portion 321, is rounded. The edge of the terminal portion 322 of the branch portion 321 connected to the ejection portion 34 is tangential to the edge of the ejection portion 34. In other words, the chamber 32 is connected to the ejection portion 34 at the terminal end of the branch portion 321. As a result, the chamber 32 is connected to the ejection portion 34, eliminating the need for a space within the branch portion 321 on the terminal side relative to the portion connected to the ejection portion 34. This prevents gas accumulation at the terminal end of the branch portion 321, thereby minimizing a drop in the ejection pressure of the oil from the oil guide 3.

[0033] As in the case of the ejection portion 34 described above, the chamber 32 is connected to the first connection portion 35 at the terminal end of the branch portion 321. Thus, as in the case of the ejection portion 34 described above, it is possible to suppress the accumulation of gas at the terminal end of the branch portion 321, thereby suppressing a decrease in the inflow pressure of the oil flowing into the core inlet flow path 22.

[0034] Back to Figure 2 The coils 4 are inserted into the first slots 20 of the stator core 2 as described above, but are also inserted into the plurality of second slots 30 of the oil deflector 3. Consequently, the plurality of coil ends 40 are mounted on the stator core 2 and the oil deflector 3, projecting axially from the oil deflector 3. Thus, by mounting the coils 4 on the stator core 2 and the oil deflector 3, the oil deflector 3 is positioned close to the coil ends 40 of the coils 4. Although not shown, the coils 4 constitute a plurality of coil groups (three in this embodiment, three phases) through which currents of different phases flow, and an insulating coating is applied to the outer surface of each coil 4.

[0035] like Figure 2 and Figure 3 As shown, the auxiliary oil guides 5 are arranged axially outward relative to the oil guide 3, and include auxiliary oil guide 5F arranged forward of the oil guide 3F, and auxiliary oil guide 5R arranged rearward of the oil guide 3R. Both auxiliary oil guides 5F and 5R are cylindrical and arranged coaxially with the oil guides 3F and 3R.

[0036] The auxiliary oil guides 5F and 5R are arranged in opposite directions and have the same shape. Therefore, for convenience of description, the following description may use the common reference numeral 5 for common items of the auxiliary oil guides 5F and 5R.

[0037] The secondary oil deflector 5 is formed from a non-magnetic material, more specifically, a resin material (e.g., SPS (syndiotactic polystyrene) or PPS (polyphenylene sulfide). The outer periphery 5p of the secondary oil deflector 5 is provided with a guide groove 50 for receiving externally supplied oil and guiding it to the oil deflector 3, and a notch 51 for draining the oil used to cool the coil ends 40 from the stator 12.

[0038] like Figure 3 As shown, the guide groove portion 50 includes: an annular groove 500, which is formed so that the axial inner end portion thereof descends radially inwardly toward the oil guide 3; and a linear groove 501, which extends axially outwardly from the upper portion of the annular groove 500. Figure 1 The oil flowing into the flow path 90 of the housing 9 drips into the linear groove 501, flows into the inlet portion 33 of the oil guide 3 from the annular groove 500, cools the coil 4, and is discharged from the inner peripheral side of the auxiliary oil guide 5 through the cutout portion 51.

[0039] <Oil Flow Pattern> Next, the flow pattern of the oil for cooling the coils 4 of the stator 12 will be described. Figure 6 is a diagram for explaining the first flow pattern. Figure 6 In the figure, for the convenience of illustration, the coil 4 is omitted, and the first connecting portion 35 and the second connecting portion 36 are not shown. Figure 7 3F and the oil flow in the stator core 2 in the front oil guide 3F in the first flow pattern. Figure 7 It is adopted Figure 5 The AA section of the diagram. Figure 6 As shown in FIG. 1 , the first flow pattern is a pattern in which oil flows from the front oil guide 3F through the inner core flow path 22R of the stator core 2 and then flows into the rear oil guide 3R. More specifically, in the first flow pattern, the oil supplied from the outside is as follows: Figure 6 and Figure 7 As shown, after being introduced by the inlet portion 33 of the front oil guide 3F, the oil flows through the chamber 32 and the first connecting portion 35 of the oil guide 3F, passes through the in-core flow path 22R of the stator core 2, and then flows through the second connecting portion 36 of the rear oil guide 3R. Figure 6 As shown, the oil is ejected from the auxiliary ejection portion 37 of the oil guide 3R toward the rear coil end 40 .

[0040] In such a first flow mode, Figure 7 As shown, the oil flowing through the core flow path 22R (space α) contacts the stator core 2 at the closed portion P2 that separates the space α, and also contacts the coil 4 at the radially outer portion 41 of the outer coil 4a that separates the space α, thereby directly cooling both the stator core 2 and the coil 4. As a result, the stator core 2 and the coil 4 can be effectively cooled.

[0041] In addition, in the first flow mode mentioned above, if Figure 7 As shown, at least a portion of the externally supplied oil, after being introduced by the inlet portion 33 of the front oil deflector 3F, flows directly from the first connection portion 35 into the in-core flow path 22R of the stator core 2. Therefore, at least a portion of the externally supplied oil is provided to the in-core flow path 22R in a fresh state, having not absorbed heat from other components of the stator 12. This allows for more effective cooling of the stator core 2 and coils 4.

[0042] Furthermore, in the first flow pattern, the oil flowing from the oil guide 3F through the in-core flow path 22R of the stator core 2 is ejected from the auxiliary ejection portion 37 of the rear oil guide 3R toward the rear coil end 40. Thus, the oil used to cool the stator core 2 can be used without waste to cool the rear coil end 40.

[0043] Although not shown in the illustration due to its commonality with the first mode, the second flow pattern is the opposite of the first flow pattern, in that oil flows from the rear oil guide 3R through the in-core flow path 22F of the stator core 2 and into the front oil guide 3F. More specifically, in the second flow pattern, externally supplied oil is introduced through the inlet portion 33 of the rear oil guide 3R, flows through the chamber 32 and first connecting portion 35 of the oil guide 3R, passes through the in-core flow path 22F of the stator core 2, and then flows through the second connecting portion 36 of the front oil guide 3F before being ejected from the auxiliary ejection portion 37 of the oil guide 3F toward the front coil end 40.

[0044] In this second flow pattern, as in the first flow pattern described above, oil flowing through the in-core flow path 22F (space α) contacts the stator core 2 at the closed portion P2 that partitions the space α. Similarly, oil contacts the coil 4 at the radially outer portion 41 of the outer coil 4a that partitions the space α, thereby directly cooling both the stator core 2 and the coil 4. This effectively cools the stator core 2 and the coil 4.

[0045] In addition, in the second flow mode, as in the above-mentioned first flow mode, at least a portion of the oil supplied from the outside is provided to the core flow path 22F in a fresh state without taking heat from other components of the stator 12, thereby further effectively cooling the stator core 2 and the coil 4.

[0046] Furthermore, in the second flow pattern, as in the first flow pattern described above, the oil passing through the in-core flow path 22F is ejected from the auxiliary ejection portion 37 of the oil guide 3F toward the front coil end 40, thereby enabling the oil used to cool the stator core 2 to be utilized without waste to cool the front coil end 40.

[0047] (Structure of the housing) Back to Figure 1 The housing 9 includes a cylindrical main body 91 and a pair of bottomed cylindrical cover portions 92 that are arranged to close the openings at the axial ends of the main body 91. A hole 920 for the shaft 10 to pass through is formed in the bottom of the cover portion 92. The cover portion 92 is fixed to the axial ends of the main body 91 using fasteners such as bolts (not shown).

[0048] When secured to the main body 91, the cover 92 contacts the secondary oil deflector 5 at its bottom inner surface 92a, located at the axial end of the stator 12, and presses the secondary oil deflector 5 axially inward. In this state, the oil deflector 3, located axially inward of the secondary oil deflector 5, is pressed axially against the stator core 2 via the secondary oil deflector 5 by the pressure of the cover 92. In other words, the housing 9 is configured to axially press the oil deflector 3 of the stator 12 against the stator core 2. This configuration of the housing 9 prevents oil leakage between the stator core 2 and the oil deflector 3 without requiring a sealing member such as an O-ring. This reduces the number of components in the motor unit A, thereby reducing the cost of the motor unit A.

[0049] According to the stator 12 described above, the space α defined within the first slot 20 of the stator core 2 by the closed portion P2 and the radially outer portion 41 of the outer coil 4a constitutes the in-core flow path 22. This allows the in-core flow path 22 to be provided within the stator core 2 without installing other components (e.g., piping) within the first slot 20. This allows the stator 12, which includes the stator core 2 having the in-core flow path 22 formed therein, to be manufactured more simply.

[0050] Furthermore, the aforementioned space α forms an in-core flow path 22. Thus, oil flowing through the in-core flow path 22 (space α) contacts the stator core 2 at the enclosed portion P2 that separates the space α. Similarly, oil contacts the coil 4 at the radially outer portion 41 of the outer coil 4a that separates the space α, thereby directly cooling both the stator core 2 and the coil 4. This effectively cools the stator core 2 and the coil 4. Consequently, a stator 12 can be provided that can be manufactured more simply and effectively cools the stator core 2 and the coil 4.

[0051] (Variation) Figure 8 1 is a front view schematically showing a portion of the stator core 2 in a modified example of the first embodiment. Figure 8 The ratio of the coil 4V shown is not limited to the actual situation. The coil 4 is not limited to the above case, and can be other than SC winding, for example, Figure 8 The coil 4V is shown as a continuous winding. Since the coil 4V generally has a smaller outer peripheral size than the above-mentioned coil 4 as an SC winding, as shown in FIG. Figure 8 As shown, in order to reliably prevent the outer coil 4av disposed radially outermost among the coils 4V from intruding into the space α, it is preferable that the lengths of the first protrusions 208 and 209 (the circumferential dimensions measured from the sidewalls 201 and 202) be set longer than the first protrusions 204 and 205. Figure 8As shown, in order to reliably prevent the inner coil 4bv, which is arranged at the radially innermost side of the coil 4V, from detaching from the first slot 20, it is preferred to set the length of the second protrusions 210 and 211 (the circumferential dimension measured from the side wall portions 201 and 202) to be longer than the above-mentioned second protrusions 206 and 207.

[0052] It should be noted that liquids other than oil can also be used as refrigerants. Furthermore, as a structure for flowing oil in the in-core flow path 22 of the stator core 2, another structure can be used instead of the oil guide 3. In this case, the coil 4 can be inserted into the plurality of first slots 20 of the stator core 2 and assembled on the stator core 2. Furthermore, the oil guide 3 can be provided at one axial end of the stator core 2. Furthermore, the oil guides 3F and 3R can have different shapes.

[0053] It should be noted that this is not limited to the above configuration. First protrusions 204 and 205 may be provided on the side walls 201 and 202 as a structure for preventing the outer coil 4a from moving radially outward, or other structures may be used in place of the first protrusions 204 and 205. Similarly, second protrusions 206 and 207 may be provided on the side walls 201 and 202 as a structure for preventing the inner coil 4b from moving radially inward, or other structures may be used in place of the second protrusions 206 and 207.

[0054] The oil guide 3 may be formed of a non-magnetic material other than resin, such as ceramic. Since the oil guide 3 is formed of a non-magnetic material, the oil guide 3 can be installed on the stator 12 without magnetically affecting the motor 1.

[0055] The above embodiments are illustrative in all respects and are not to be construed as limiting. Therefore, the technical scope of the present invention is not to be interpreted solely by the above embodiments and examples, but is to be defined based on the claims. Furthermore, variations and modifications falling within the scope of equivalents of the claims are intended to fall within the scope of the present invention.

[0056] The present disclosure is described based on embodiments, but it should be understood that the present disclosure is not limited to the embodiments and structures. The present disclosure also includes various modifications and variations within the scope of equality. In addition, various combinations or forms, further including only one element, more than one element, or less than one element, also fall within the scope and scope of the present disclosure.

Claims

1. A stator, comprising: A cylindrical stator core having a plurality of slots extending therethrough in the axial direction; and a coil assembled on the stator core by being inserted into a plurality of the slots, characterized in that The inner wall portion of the slot includes a pair of side wall portions extending radially outward from the inner circumference of the stator core and circumferentially opposite to each other, and a bottom wall portion connected to each end of the pair of side wall portions, so that the slot opens radially inward. The outer coil disposed radially outermost among the coils in the slot is spaced apart from the bottom wall in the radial direction, so that a space is formed between the outer coil and the bottom wall. The space portion constitutes an in-core flow path through which refrigerant flows.

2. The stator according to claim 1, characterized in that The pair of side wall portions are provided with first protrusions configured to prevent the outer coil from moving radially outward.

3. The stator according to claim 1, characterized in that The pair of side wall portions are provided with second protrusions configured to prevent radially inward movement of an inner coil, which is arranged radially innermost among the coils in the slot.

4. The stator according to claim 1, characterized in that An annular guide member is provided on at least one end side of the stator core in the axial direction and is coaxially arranged with the stator core. The guide member is provided with: an introduction portion for introducing refrigerant supplied from the outside; and a core connecting portion communicating with the introduction portion and connected to an inlet of the core inlet flow path.

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