Rotating electrical machine and vehicle drive device equipped with the same

Abstract

To provide a rotary electrical machine having improved cooling performance.SOLUTION: A rotary electrical machine according to the present invention comprises: a stator 301; a rotor 302; and a cooling passage through which a refrigerant for cooling the stator 301 and the rotor 302 flows. The cooling passage includes: a refrigerant inlet 343 through which the refrigerant is introduced; stator cooling passages 3013 communicating with the refrigerant inlet 343; a rotor cooling passage 304; and a connection passage 315 connecting the stator cooling passages 3013 with the rotor cooling passage 304. The rotor cooling passage 304 includes: refrigerant outlets 306a, 306b through which the refrigerant is discharged radially outside the rotor 302 in association with rotational motion of the rotor 302. A plurality of the stator cooling passages 3013 are arranged in the circumferential direction of a stator core 3010. The terminal end of each of the stator cooling passages 3013 is connected to the upstream side of the connection passage 315 at a position opposite to the refrigerant inlet 343 in the axial direction and in the circumferential direction.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a rotating electrical machine and a vehicle drive device including the same.

Background Art

[0002] As a technique for cooling a rotating electrical machine, for example, there are techniques described in Patent Documents 1 to 3. In Patent Document 1, a rotor, a rotor shaft connected to the rotor, a stator disposed on the outer periphery of the rotor, and a housing disposed so as to cover the outer periphery of the stator are provided. The housing is provided with a refrigerant supply port. A first cooling passage for flowing the refrigerant supplied from the refrigerant supply port is formed between the housing and the stator. A second refrigerant passage is formed in the rotor shaft. One ends of two branch passages are connected to the first cooling passage, and the second cooling passage is connected to the other ends of the two branch passages. Then, by flowing the refrigerant through the first refrigerant passage and the second refrigerant passage branched and connected from the first refrigerant passage, the rotating electrical machine is cooled.

[0003] In Patent Document 2, a rotary pump, an oil passage disposed in the casing, and an oil passage disposed on the motor rotating shaft and extending in the axial direction are provided. The oil passage disposed in the casing extends radially outward from the rotary pump, bends, extends in the axial direction, further bends, and extends radially inward, and is connected to the oil passage disposed on the motor rotating shaft. An oil passage extending radially outward is connected to the oil passage disposed on the motor rotating shaft. The oil passage extending radially outward is connected to a holder portion that is located radially outward and holds the rotor. An oil hole that opens toward the coil of the stator is formed in the holder portion. Then, the lubricating oil pumped by the rotary pump passes through the oil passage disposed in the casing, the oil passage disposed on the motor rotating shaft, and the oil passage extending radially outward, and is discharged from the oil hole formed in the holder portion to cool the coil of the stator.

[0004] In Patent Document 3, a first reservoir is provided in the upper regions of the center frame, the front frame, and the rear frame that constitute the housing, and the cooling oil pumped from the pump is stored in this first reservoir. The cooling oil stored in the first reservoir is ejected from the coil ejection holes provided in the front frame and the rear frame, and the stator and the bearing are cooled by the weight of the cooling oil.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the technology described in Patent Document 1, since the refrigerant is branched from the first cooling passage and introduced into the second cooling passage through two branch passages, there is a problem that the flow rate of the refrigerant decreases and the cooling performance of the stator, rotor, and bearing that constitute the rotating electrical machine deteriorates.

[0007] In the technology described in Patent Document 2, although the oil passage is arranged in the casing, the cooling of the stator is not considered.

[0008] In the technology described in Patent Document 3, since the stator and the bearing are cooled by the weight of the cooling oil, there is a problem that the cooling oil cannot flow uniformly and the cooling performance of the stator and the bearing deteriorates.

[0009] An object of the present invention is to provide a rotating electrical machine with improved cooling performance and a vehicle drive device equipped with the same.

Means for Solving the Problems

[0010] In order to achieve the above object, the present invention provides a rotating electrical machine comprising a stator, a rotor, and a cooling flow path through which a refrigerant for cooling the stator and the rotor flows. The cooling flow path includes a refrigerant inlet for introducing the refrigerant, a stator cooling flow path formed in a stator core of the stator and communicating with the refrigerant inlet, a rotor cooling flow path formed inside the rotor, and a connection flow path connecting the stator cooling flow path and the rotor cooling flow path. The rotor cooling flow path is provided with a refrigerant discharge hole for discharging the refrigerant radially outward of the rotor along with the rotational movement of the rotor. The stator cooling flow paths are arranged in plurality in the circumferential direction of the stator core, and each end of the plurality of stator cooling flow paths is connected to an upstream side of the connection flow path at a position axially opposite and circumferentially opposite to the refrigerant inlet.

Advantages of the Invention

[0011] According to the present invention, it is possible to provide a rotating electrical machine with improved cooling performance and a vehicle drive device including the same.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Mode for Carrying Out the Invention

[0013] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The same reference numerals are given to the same components, and the same description will not be repeated.

[0014] The various components of the present invention do not necessarily have to exist independently of each other. It is acceptable that one component is composed of a plurality of members, a plurality of components are composed of one member, a certain component is a part of another component, or a part of a certain component overlaps with a part of another component.

[0015] FIG. 1 is a schematic configuration diagram of an electric vehicle according to an embodiment of the present invention. In FIG. 1, an e-Axle unit 3 for driving wheels 2 is mounted on a vehicle body 1. The e-Axle unit 3 is a drive unit in which devices such as a motor as a rotating electric machine and an inverter are integrated.

[0016] In the figure, as indicated by the arrow, the side where the e-Axle unit 3 transmits the driving force is defined as the load side, the opposite side is defined as the anti-load side, the upward direction is defined as the upper part / upper side, and the downward direction is defined as the lower part / lower side. Also, the direction along the rotor shaft is defined as the axial direction, the circumferential direction around the rotor shaft is defined as the circumferential direction, and the direction orthogonal to the horizontal line is defined as the vertical direction.

[0017] An oil cooler 4 is connected to the e-Axle unit 3. The oil cooler 4 is equipped with a pump for pumping the refrigerant, and the refrigerant is passed through the devices in the e-Axle unit 3 to cool these devices. Also, the oil cooler 4 is connected to a chiller 6 via a pipe 5. After the refrigerant cools the devices in the e-Axle unit 3, it is sent to the chiller 6 via the pipe 5. In the chiller 6, the heated refrigerant is cooled by the running wind when the vehicle is running. The cooled refrigerant is sent back to the oil cooler 4 again.

[0018] Figure 2 is an external perspective view of the e-Axle unit according to an embodiment of the present invention as viewed from the anti-load side. Figure 3 is a sectional perspective view taken along line III-III of Figure 2. Figure 4 is a sectional perspective view of Figure 3 as viewed from the load side. Figure 5 is a sectional view taken along line III-III of Figure 2. Note that Figures 3 and 4 show a state where the motor cover, stator, rotor, and rotor shaft are shifted to the right side (load side) in the axial direction. Figure 6 is a perspective view of the motor housing according to an embodiment of the present invention as viewed from the open side. Figure 7 is a perspective view of the motor housing according to an embodiment of the present invention as viewed from the bottom side of the motor housing. Figure 8 is an external perspective view of the inverter section according to an embodiment of the present invention as viewed from the load side. Figure 9 is a sectional perspective view obtained by sectioning Figure 8 in the vertical direction.

[0019] As shown in Figure 2, the e-Axle unit 3 includes a motor section 30, an inverter section 31, and a transmission mechanism section 32. The e-Axle unit 3 of this embodiment functions as a vehicle drive device.

[0020] As shown in FIGS. 3 to 5, the motor unit 30 includes a stator 301 and a rotor 302 rotatably supported on the inner circumferential side of the stator 301. The stator 301 includes a stator core 3010 and a stator coil 3012. The rotor 302 is provided with a rotor shaft 303 that rotates together with the rotor 302.

[0021] The outer circumference of the stator 301 is covered by a motor housing 34. The motor housing 34 houses the stator 301 and the rotor 302. The motor housing 34 is formed in a bottomed cylindrical shape with one axial load side open, and the open side is covered by a motor cover 35. The non-load side of the motor housing 34 is closed by a motor housing bottom 36 integrally formed with the motor housing 34. The motor cover 35 and the motor housing bottom 36 are provided with bearings 37 and 38 for rotatably supporting the rotor shaft 303.

[0022] The transmission mechanism unit 32 is provided with a speed reducer 321. The speed reducer 321 is fixed to the rotor shaft 303, and transmits the driving force of the motor unit to the vehicle via the speed reducer 321 to drive the vehicle.

[0023] The inverter unit 31 is externally configured by an inverter housing 310 with one axial load side open, and the open portion on the load side is closed by an inverter cover 311. An inverter that supplies power to the motor unit 30 is housed in the inverter housing 310. The inverter housing 310 is provided on the motor housing 34 via the inverter cover 311.

[0024] A first flange portion 341 extending in a direction orthogonal to the axial direction is formed on the axial load side of the motor housing 34, and a second flange portion 342 extending in a direction orthogonal to the axial direction is formed on the non-axial load side.

[0025] The first flange portion 341 of the motor housing 34 is arranged such that the third flange portion 351 of the motor cover 35 faces it, and the open portion on the load side of the motor housing 34 is closed by the motor cover 35.

[0026] The second flange portion 342 of the motor housing 34 is arranged such that the fourth flange portion 312 of the inverter portion 31 faces it. As a result, the inverter cover 311 is arranged to face the bottom 36 of the motor housing.

[0027] A refrigerant inlet 343 for introducing refrigerant into the motor portion 30 is formed at the upper part of the motor housing 34. Also, refrigerant outlets 344a, 344b for discharging the refrigerant in the motor portion 30 are formed at the lower part of the motor housing 34. In the case of this embodiment, one refrigerant inlet 343 and two refrigerant outlets 344a, 344b are formed.

[0028] An annular first protrusion 352 protruding toward the motor housing 34 side (anti-load side) is formed on the motor cover 35. A groove-shaped annular cooling flow path 353 (first cooling flow path) through which refrigerant flows is formed in this first protrusion 352. Also, a refrigerant introduction communication port 354 communicating with the refrigerant inlet 343 is formed in the first protrusion 352. When the open portion on the load side of the motor housing 34 is closed by the motor cover 35, the first protrusion 352 presses the stator core 3010 in the axial direction. Also, the stator core 3010 is pressed by the first protrusion 352, and the surface on the side opposite to the first protrusion 352 (anti-load side) is pressed by the second protrusion 346.

[0029] The annular cooling flow path 353 (the first cooling flow path) is continuously formed in an annular shape, but the lowermost part is blocked by a blocking portion 355. And a refrigerant discharge communication port 356 communicating with the refrigerant discharge port 344a is formed in the blocking portion 355. The refrigerant discharge communication port 356 is formed so as to penetrate the first protruding portion 352 in the vertical direction and communicates with the accommodation space 345 of the stator 301 and the rotor 302. On the other hand, the refrigerant introduction communication port 354 does not penetrate the first protruding portion 352 and does not communicate with the accommodation space 345.

[0030] Also, the first protruding portion 352 is provided with an annular gasket 357 that suppresses refrigerant leakage when contacting the stator 301. The gasket 357 is disposed on the inner circumferential side of the annular cooling flow path 353 (the first cooling flow path).

[0031] As shown in FIGS. 3 to 6, a second protruding portion 346 protruding toward the open side (load side) is formed on the bottom portion 36 of the motor housing (motor housing 34). An annular cooling flow path 347 (the third cooling flow path) through which the refrigerant flows is formed in the second protruding portion 346.

[0032] The annular cooling flow path 347 (the third cooling flow path) is continuously formed in an annular shape, but the lowermost part is blocked by a blocking portion 348. And a refrigerant discharge communication port 349 communicating with the refrigerant discharge port 344b is formed in the blocking portion 348.

[0033] Also, the second protruding portion 346 is provided with an annular gasket 3410 that suppresses refrigerant leakage when contacting the stator 301. The gasket 3410 is disposed on the inner circumferential side of the annular cooling flow path 347 (the third cooling flow path).

[0034] Also, as shown in FIG. 7, two (a plurality of) bottom through-holes 361 communicating with the annular cooling flow path 347 (the third cooling flow path) are formed in the bottom portion 36 of the motor housing (motor housing 34). The bottom through-holes 361 are arranged at positions that do not overlap with the refrigerant discharge communication port 349.

[0035] A bearing opening 362 for arranging a bearing 38 that holds a rotor shaft 303 is formed at the center of the bottom 36 (motor housing 34) of the motor housing.

[0036] As shown in FIGS. 3 and 4, a part of the rotor shaft 303 is hollow, and a rotor cooling flow path 304 (the fifth cooling flow path) through which a refrigerant flows is formed inside. The rotor shaft 303 on the axially opposite side (load side) where the rotor cooling flow path 304 is formed is solid.

[0037] As shown in FIGS. 8 and 9, a plurality of inverter cover through-holes 313 communicating with a plurality of bottom through-holes 361 formed in the bottom 36 of the motor housing are formed in the inverter cover 311 of the inverter unit 31. An inverter 319 for driving the electric motor is accommodated inside the inverter unit 31.

[0038] An insertion opening 314 into which an end of the rotor 302 is inserted is formed at the center of the inverter cover 311. Further, on the side of the inverter cover 311 opposite to the load side, two connection flow paths 315 (the fourth refrigerant flow path) formed in an inverted V shape are provided. One of the connection flow paths 315 is connected to a plurality of inverter cover through-holes 313, and the other opens toward the insertion opening 314. Then, with the rotor shaft 303 inserted into the insertion opening 314, the other of the connection flow paths 315 communicates with the rotor cooling flow path 304 (the fifth cooling flow path) of the rotor shaft 303. An oil seal 316 is arranged at the end of the rotor shaft 303 connected to the connection flow path 315 to suppress leakage of the refrigerant.

[0039] A refrigerant discharge port 344b for discharging the refrigerant to the outside is positioned between the two connection flow paths 315.

[0040] In the annular cooling flow path 347 (the third cooling flow path), the refrigerant gathers downward due to gravity, and the gathered refrigerant passes through the plurality of bottom through-holes 361 and the plurality of inverter cover through-holes 313. The refrigerant that has passed through these passes through the two connection flow paths 315 and is sent to the rotor cooling flow path 304 of the rotor shaft 303.

[0041] In this embodiment, the connection flow path 315 is provided inside the inverter housing 310. However, the connection flow path 315 may form a space with the motor unit 30 (the bottom 36 of the motor housing) or the inverter housing 310 and the motor housing 34, and may be provided in this space. By providing at least a part of the connection flow path 315 inside the inverter housing 310 or in the space formed by the inverter housing 310 and the motor housing 34, the inverter can exchange heat with the refrigerant, and the inverter unit and the motor unit can be efficiently cooled.

[0042] FIG. 10 is an external perspective view of the rotor according to the embodiment of the present invention as viewed from the anti-load side. FIG. 11 is an external perspective view of the rotor shaft according to the embodiment of the present invention as viewed from the anti-load side.

[0043] The rotor 302 is provided with a rotor shaft 303 and end members 305a and 305b disposed at both ends of the rotor shaft 303. The end members 305a and 305b are disposed to suppress the axial protrusion of a plurality of permanent magnets (not shown) disposed on the rotor 302. Note that FIG. 11 shows a state in which the rotor 302 and one of the end members 305b are removed.

[0044] On the outer periphery of the rotor shaft 303, a plurality of refrigerant discharge ports 306a and 306b communicating with the rotor cooling flow path 304 are formed. The refrigerant discharge ports 306a and 306b are arranged, for example, four at intervals of 90 degrees in the circumferential direction of the rotor shaft 303. Further, the refrigerant discharge ports 306a and 306b are arranged at two positions in the axial direction in accordance with the positions of the end members 305a and 305b. As a result, a total of eight refrigerant discharge ports 306a and 306b are provided on the rotor shaft.

[0045] The end members 305a and 305b are formed with a plurality of discharge channels 307a and 307b (the sixth cooling channel) that communicate with a plurality of refrigerant discharge ports 306a and 306b. The discharge channels 307a and 307b communicate with the rotor cooling channel 304 via the refrigerant discharge ports 306a and 306b.

[0046] Next, the configuration of the stator will be described. FIG. 12 is an external perspective view of the stator according to an embodiment of the present invention.

[0047] The stator 301 includes a stator core 3010 that constitutes the outer contour of the stator 301, and a plurality of slots 3011 that are formed to open from the outer peripheral side to the inner peripheral side of the stator core 3010 and into which the stator coil 3012 (see FIGS. 3 and 4) is inserted. Further, a plurality of stator cooling channels 3013 (the second cooling channel) are formed in the stator core 3010 on the outer peripheral side of the slots 3011. The stator cooling channels 3013 are formed to penetrate the axial direction of the stator core 3010. Further, the plurality of stator cooling channels 3013 have the same cross-sectional shape perpendicular to the axial direction and are arranged at equal intervals in the circumferential direction.

[0048] In a state where the stator 301 is inserted into the motor housing 34 and the open portion of the motor housing 34 is closed by the motor cover 35, the stator cooling channels 3013 communicate with an annular cooling channel 353 (the first cooling channel) and an annular cooling channel 347 (the third cooling channel). The stator cooling channels 3013 communicate with the refrigerant inlet 343 via the annular cooling channel 353.

[0049] Next, with reference to FIGS. 3 to 13, the flow path configuration of the refrigerant will be described. FIG. 13 is a schematic diagram showing the flow of the refrigerant according to an embodiment of the present invention.

[0050] A pump provided in the oil cooler 4 (Fig. 1) is connected to the refrigerant inlet 343, and the refrigerant is pumped by this pump. The refrigerant introduced from the refrigerant inlet 343 flows through the annular cooling channel 353 (first cooling channel), the stator cooling channel 3013 (second cooling channel), the annular cooling channel 347 (third cooling channel), the connection channel 315 (fourth refrigerant channel), the rotor cooling channel 304 (fifth cooling channel), and the discharge channels 307a, 307b (sixth cooling channel) as described below, and is discharged from the refrigerant outlets 344a, 344b.

[0051] The refrigerant pumped by the pump flows into the motor section 30 from the refrigerant inlet 343 disposed at the upper part of the motor housing 34. After flowing along the annular cooling channel 353 (first cooling channel) in the motor section 30, the refrigerant flows into the stator cooling channel 3013 (second cooling channel) communicating with the annular cooling channel 353 (first cooling channel). Although a plurality of stator cooling channels 3013 are provided in the circumferential direction of the stator core 3010, since the refrigerant is pressurized by the pump, it flows uniformly through the plurality of stator cooling channels 3013 regardless of the vertical position.

[0052] An annular gasket 357 is provided between the motor cover 35 and the stator core 3010. In this embodiment, the gasket 357 is provided on the first protruding portion 352. The annular gasket 357 presses against the stator core 3010 to suppress the leakage of the refrigerant from the connection portion between the annular cooling channel 353 (first cooling channel) and the stator cooling channel 3013 (second cooling channel). When the refrigerant passes through the stator cooling channel 3013, it takes away the heat generated by the stator 301 and cools the stator 301.

[0053] The refrigerant that has passed through the plurality of stator cooling channels 3013 (second cooling channels) flows into the annular cooling channel 347 (third cooling channel). The refrigerant flowing through the annular cooling channel 347 is promoted to flow by gravity and flows to the lower part of the annular cooling channel 347. That is, the end of each of the plurality of stator cooling channels 3013 is located at the lower part.

[0054] The refrigerant that has flowed to the lower part of the annular cooling flow path 347 passes through the bottom through-hole 361 formed in the bottom 36 of the motor housing and the inverter cover through-hole 313 formed in the inverter cover 311, and flows into the two connection flow paths 315 (the fourth refrigerant flow path) formed in an inverted V shape. The inlet (upstream side) of the connection flow path 315 is arranged vertically below the refrigerant inlet 343. And the inlet (upstream side) of the connection flow path 315 communicates with the respective ends of the stator cooling flow path 3013 via the annular cooling flow path 347 (the third cooling flow path), the bottom through-hole 361, and the inverter cover through-hole 313. When viewed in relation to the refrigerant inlet 343, the respective ends of the plurality of stator cooling flow paths 3013 are connected to the inlet (upstream side) of the connection flow path 315 at positions on the opposite side (anti-load side) in the axial direction and the opposite side (lower side) in the circumferential direction from the refrigerant inlet 343.

[0055] The refrigerant that has flowed into the connection flow path 315 rises within the connection flow path 315. The refrigerant passing through the connection flow path 315 takes away the heat generated by the inverter 319 in contact with the connection flow path 315 and cools the inverter 319.

[0056] The refrigerant that has passed through the connection flow path 315 flows into the rotor cooling flow path 304 (the fifth cooling flow path). The connection flow path 315 connects the stator cooling flow path 3013 and the rotor cooling flow path 304. The rotor cooling flow path 304 is provided with refrigerant discharge ports 306a, 306b that discharge the refrigerant radially outward of the rotor 302 along with the rotational movement of the rotor 302.

[0057] The refrigerant that has flowed into the rotor cooling flow path 304 passes through the refrigerant discharge ports 306a, 306b and is discharged into the accommodation space 345 from the openings of the discharge flow paths 307a, 307b. In this way, the refrigerant that has passed through each flow path and flowed in from the refrigerant inlet 343 is discharged into the accommodation space 345 from the openings of the discharge flow paths 307a, 307b. Since the axial end on the side opposite to the connection flow path 315 (load side) of the rotor shaft 303 is solid, refrigerant does not leak from the axial end.

[0058] When the rotor 302 rotates, the refrigerant discharged from the openings of the discharge channels 307a and 307b increases in flow velocity due to the centrifugal pump effect and is discharged into the accommodation space 345 of the motor housing 34, hitting the stator coil 3012. The refrigerant efficiently hits the stator coil 3012, takes away the heat of the stator coil 3012, and cools the stator coil 3012.

[0059] The refrigerant discharged into the accommodation space 345 of the motor housing 34 passes through the refrigerant discharge communication ports 356 and 349 and is discharged from the refrigerant discharge ports 344a and 344b respectively. The refrigerant discharged from the refrigerant discharge ports 344a and 344b flows through the pipe 5 (Fig. 1), reaches the chiller 6, is cooled by the running wind, and is guided to the oil cooler 4. In this way, the refrigerant circulates within the e-Axle unit 3 and cools the devices within the e-Axle unit 3.

[0060] In this embodiment, the refrigerant inlet 343 is located at the upper part of the motor section 30, is connected to the stator cooling channel 3013 (second cooling channel), and is the end of the annular cooling channel 347 (third cooling channel). The bottom through-hole communicating with the inlet of the connection channel 315 is located at the lower part of the motor section 30. That is, the refrigerant inlet 343 and the end of the annular cooling channel 347 are arranged at positions symmetrical to the rotor shaft 303 in the circumferential direction. Thereby, the pressure losses in the plurality of stator cooling channels 3013 can be equalized, and the uneven flow of the refrigerant during the refrigerant flow due to the centrifugal pump effect caused by the rotation of the rotor 302 can be suppressed.

[0061] According to this embodiment, since the end of the stator cooling channel 3013 and the rotor cooling channel 304 are connected via the connection channel 315, the flow of the refrigerant in the entire stator cooling channel can be promoted by the centrifugal pump effect caused by the rotation of the rotor 302.

[0062] Further, according to the present embodiment, since each end of the plurality of stator cooling channels 3013 is connected to the inlet (upstream side) of the connection channel 315 at a position axially opposite (anti-load side) and circumferentially opposite (lower side) to the refrigerant inlet 343, the pressure loss of the stator cooling channels 3013 can be equalized to suppress uneven flow, and the cooling performance of the stator 301 can be improved.

[0063] Also, according to the present embodiment, since the upstream side of the connection channel 315 is arranged vertically below the refrigerant inlet 343, the flow of the refrigerant can be promoted by gravity, and the cooling performance can be improved.

[0064] In the above-described present embodiment, the inlet (upstream side) of the connection channel 315 was arranged vertically below the refrigerant inlet 343, but the present invention is not limited to this configuration. For example, it may be configured as shown in FIG. 14. FIG. 14 is a schematic diagram showing the flow of the refrigerant according to another embodiment of the present invention.

[0065] In FIG. 14, the refrigerant inlet 343 is positioned vertically below, and the mouth (upstream side) of the connection channel 315 is positioned vertically above. That is, the refrigerant inlet 343 is positioned vertically below the upstream side of the connection channel 315. In FIG. 14, by positioning the refrigerant inlet 343 vertically below, the pressure loss from the accommodation space 345 (FIG. 5) of the motor unit 30 to the refrigerant inlet 343 can be reduced. Since the refrigerant discharged into the accommodation space 345 accumulates below the accommodation space 345 by gravity, the refrigerant discharge port may be formed at an arbitrary position.

[0066] Note that the present invention is not limited to the above-described embodiments, and includes various modifications. The above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described.

Explanation of Reference Numerals

[0067] 1... Vehicle body, 2... Wheel, 3... e-Axle unit, 4... Oil cooler, 5... Pipe, 6... Chiller, 30... Motor part, 31... Inverter part, 32... Transmission mechanism part, 34... Motor housing, 35... Motor cover, 36... Bottom of motor housing, 37, 38... Bearing, 301... Stator, 3010... Stator core, 3011... Slot, 3012... Stator coil, 3013... Stator cooling flow path (second cooling flow path), 302... Rotor, 303... Rotor shaft, 304... Rotor cooling flow path (fifth cooling flow path), 305a, 305b... End member, 306a, 306b... Refrigerant discharge port, 307a, 307b... Discharge flow path, 310... Inverter housing, 311... Inverter cover, 312... Fourth flange part, 313... Inverter cover through hole, 314... Insertion opening, 315... Connection flow path (fourth refrigerant flow path), 316... Oil seal, 319... Inverter, 321... Reducer, 341... First flange part, 342... Second flange part, 343... Refrigerant inlet, 344a, 344b... Refrigerant discharge port, 345... Accommodation space, 346... Second protrusion, 347... Annular cooling flow path (third cooling flow path), 348... Blocking part, 349... Refrigerant discharge communication port, 3410... Gasket, 351... Third flange part, 352... First protrusion, 353... Annular cooling flow path (first cooling flow path), 354... Refrigerant introduction communication port, 355... Blocking part, 356... Refrigerant discharge communication port, 357... Gasket, 361... Bottom through hole, 362... Bearing opening

Claims

1. A rotating electrical machine comprising a stator, a rotor, and a cooling flow path through which a refrigerant for cooling the stator and the rotor flows, wherein the cooling flow path includes a refrigerant inlet for introducing the refrigerant, a stator cooling flow path formed in a stator core of the stator and communicating with the refrigerant inlet, a rotor cooling flow path formed inside the rotor, and a connection flow path connecting the stator cooling flow path and the rotor cooling flow path, the rotor cooling flow path includes a refrigerant discharge port that discharges the refrigerant radially outward of the rotor as the rotor rotates, the stator cooling flow paths are arranged in a plurality in the circumferential direction of the stator core, and each end of the plurality of stator cooling flow paths is connected to an upstream side of the connection flow path at a position axially opposite and circumferentially opposite to the refrigerant inlet. A rotating electrical machine characterized by this.

2. The rotating electrical machine according to claim 1, wherein an upstream side of the connection flow path is arranged vertically below the refrigerant inlet. A rotating electrical machine characterized by this.

3. The rotating electrical machine according to claim 2, wherein two connection flow paths are formed, and a refrigerant discharge port for discharging the refrigerant to the outside is arranged between the two connection flow paths. A rotating electrical machine characterized by this.

4. The rotating electrical machine according to claim 1, wherein the refrigerant inlet is arranged vertically below an upstream side of the connection flow path. A rotating electrical machine characterized by this.

5. The rotating electrical machine according to claim 1, wherein a cross-sectional shape perpendicular to the axial direction of the stator cooling flow path is the same and the stator cooling flow paths are arranged at equal intervals in the circumferential direction. A rotating electrical machine characterized by this.

6. The rotating electrical machine according to any one of claims 1 to 5, wherein a pump is connected to the refrigerant inlet, and the refrigerant is pumped by the pump. A rotating electrical machine characterized by this.

7. The rotating electrical machine according to any one of claims 1 to 6, wherein the rotor cooling flow path is formed inside a rotor shaft, and an end portion of the rotor shaft connected to the connection flow path is provided with an oil seal. A rotating electrical machine characterized by this.

8. The rotating electrical machine according to claim 7, wherein an axial end portion of the rotor shaft on the side opposite to the connection flow path is solid. A rotating electrical machine characterized by this.

9. The rotating electrical machine according to any one of claims 1 to 8, including a motor housing that houses the stator and the rotor. The motor housing is formed in a bottomed cylindrical shape with one axial end open, and the open side of the motor housing is covered by a motor cover. The motor cover is characterized in that when the open side of the motor housing is closed, a protrusion for axially pressing the stator core is formed. A rotating electrical machine.

10. The rotating electrical machine according to claim 9, wherein a gasket for suppressing leakage of the refrigerant is disposed between the motor cover and the stator core. A rotating electrical machine.

11. The rotating electrical machine according to claim 9, wherein the motor housing is provided with an inverter housing for accommodating an inverter, and at least a part of the connection flow path is provided inside the inverter housing or in a space formed by the inverter housing and the motor housing. A rotating electrical machine.

12. A vehicle drive device including a stator, a rotor, a rotor shaft provided on the rotor, and a speed reducer fixed to the rotor shaft, and driving a vehicle via the speed reducer, wherein the vehicle drive device includes the rotating electrical machine according to any one of claims 1 to 11.

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