Electric driving device

Abstract

To sufficiently cool an inner peripheral part of a control device, and thereby suppress deviation of a temperature in the control device.SOLUTION: An electric driving device 16 includes a rotary electric machine 31 and a control device 32. The rotary electric machine 31 has a hollow shaft 38 extending in a predetermined axial direction, and a housing 36 extending in the axial direction on the outer periphery of the shaft 38. The shaft 38 has a body part 55 stored in the housing 36 and an extension part 56 extending from the body part 55, and a shaft hole 59 is provided in the extension part 56. The control device 32 has a casing 74 extending in the axial direction on the outer periphery of the extension part 56, and a ventilation port 103 is provided on the casing 74. A cooling air passage 229 extending in the axial direction is formed on the outer periphery of the casing 74, and the cooling air passage 229 communicates with the internal space of the shaft 38 through the shaft hole 59, the internal space of the casing 74, and the ventilation port 103.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an electric drive device. [Background technology]

[0002] In recent years, efforts to realize a low-carbon or carbon-free society have become more active, and research and development into electrification technologies is being conducted in vehicles, aircraft, and other vehicles to reduce CO2 emissions and improve energy efficiency.

[0003] For example, Patent Document 1 discloses an electromechanically integrated electric drive device (integrally controlled motor) that includes a rotating electric machine (electric machine) with a shaft and a control device (electronic control unit) that controls the rotating electric machine. As shown in Fig. 5 of Patent Document 1, centrifugal blades (multiple rotating blades) are attached to the shaft between the rotating electric machine and the control device. When these centrifugal blades rotate, a pressure difference occurs between the internal space of the rotating electric machine and the internal space of the control device, and an air flow is generated from the internal space of the control device toward the internal space of the rotating electric machine. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2023 / 57718 Summary of the Invention [Problem to be solved by the invention]

[0005] In Patent Document 1, air introduced from the outer periphery of the control device passes through the inner periphery of the control device and flows into the internal space of the rotating electrical machine (see the arrows in Figure 9 of Patent Document 1). As a result, the air that has been warmed by heat exchange with the outer periphery of the control device passes through the inner periphery of the control device. With this type of air flow, it is not possible to sufficiently cool the inner periphery of the control device, which is prone to heat buildup, and there is a risk of significant temperature imbalance within the control device.

[0006] In view of the above background, an object of the present invention is to suppress temperature unevenness in a control device by sufficiently cooling the inner peripheral portion of the control device, and by extension, to contribute to improvement of energy efficiency.

Means for Solving the Problems

[0007] In order to solve the above problems, an aspect of the present invention is an electric drive device (16) including a rotating electrical machine (31) and a control device (32) integrated with the rotating electrical machine and controlling the drive of the rotating electrical machine. The rotating electrical machine has a hollow shaft (38) extending in a predetermined axial direction and a housing (36) extending in the axial direction on the outer periphery of the shaft. The shaft has a main body portion (55) accommodated in the housing and an extension portion (56) extending from the main body portion toward the control device side. A shaft hole (59) penetrating from the inner peripheral surface to the outer peripheral surface is provided in the extension portion. The control device has a casing (74) extending in the axial direction on the outer periphery of the extension portion. A ventilation port (103) penetrating from the inner peripheral surface to the outer peripheral surface is provided in the casing. A cooling air passage (229) extending in the axial direction is formed at a position where the ventilation port faces on the outer periphery of the casing. The cooling air passage communicates with the internal space of the shaft via the shaft hole, the internal space of the casing, and the ventilation port.

[0008] According to this aspect, when a negative pressure is generated at the ventilation port by the cooling air passing through the cooling air passage, the air in the internal space of the shaft is taken into the cooling air passage through the shaft hole, the internal space of the casing, and the ventilation port due to this negative pressure. As a result, the air in the internal space of the shaft flows into the cooling air passage through the inner peripheral portion and the outer peripheral portion of the internal space of the casing, and the inner peripheral portion and the outer peripheral portion of the control device can be effectively cooled. In particular, the air in the internal space of the shaft is first introduced into the inner peripheral portion of the internal space of the casing. Therefore, the inner peripheral portion of the control device where heat is likely to be trapped can be sufficiently cooled, and temperature unevenness in the control device can be suppressed.

[0009] In the above aspect, the electric drive device may further include a fan (33) that rotates integrally with the shaft to introduce cooling air into the cooling air passage.

[0010] According to this aspect, a large amount of cooling air can be forcibly introduced into the cooling air passage by the fan. Along with this, the negative pressure generated at the ventilation port can be increased, and the flow rate of the air taken into the cooling air passage from the internal space of the casing through the ventilation port by this negative pressure can be increased. Therefore, the cooling effect on the control device can be enhanced.

[0011] In the above aspect, the shaft may further include a protruding portion (57) that protrudes from the main body portion toward the side opposite to the control device, the fan may be disposed on the side opposite to the control device with the rotating electric machine interposed therebetween, and may be fixed to the protruding portion.

[0012] According to this aspect, the fan can be easily fixed to the shaft as compared with the case where the fan is installed inside the rotating electric machine, inside the control device, or between the rotating electric machine and the control device.

[0013] In the above aspect, the electric drive device may further include a duct cover (34) that covers the outer peripheries of the rotating electric machine, the control device, and the fan, and the cooling air passage may be formed between the duct cover, the housing, and the casing.

[0014] According to this aspect, the cooling air introduced into the cooling air passage by the fan can be smoothly flowed along the outer peripheral surfaces of the housing and the casing.

[0015] In the above aspect, the shaft hole may be disposed on the rotating electric machine side rather than at the central portion in the axial direction of the control device, and the ventilation port may be disposed on the side opposite to the rotating electric machine with the central portion in the axial direction of the control device interposed therebetween.

[0016] According to this aspect, by separating the axial position of the shaft hole from the axial position of the ventilation port, the distance from the shaft hole to the ventilation port (i.e., the flow distance of air in the internal space of the casing) can be increased. Thereby, the heat exchange time between the air flowing through the internal space of the casing and the components of the control device can be lengthened, and the cooling effect on the control device can be enhanced.

[0017] In the above aspect, a plurality of the shaft holes may be provided at intervals in the circumferential direction of the shaft, and a plurality of the ventilation ports may be provided at intervals in the circumferential direction of the casing.

[0018] According to this aspect, the flow rate of air taken into the internal space of the casing from the internal space of the shaft through the shaft hole and the flow rate of air taken into the cooling air passage from the internal space of the casing through the ventilation port can be increased. Thereby, the cooling performance for the control device can be enhanced.

[0019] In the above aspect, the rotating electric machine further has a lid body (37) that closes the opening on the side of the housing opposite to the control device, the lid body is provided with an air intake port (53) penetrating in the axial direction, the rotating electric machine or the control device is provided with a partitioning member (89) that partitions the internal space of the housing and the internal space of the casing, the partitioning member is provided with a circulation hole (217) penetrating in the axial direction, and the cooling air passage may communicate with the air intake port through the internal space of the housing, the circulation hole, the internal space of the casing, and the ventilation port.

[0020] According to this aspect, by partitioning the internal space of the housing and the internal space of the casing with a partitioning member, the mutual thermal influence between the components of the rotating electrical machine and the components of the control device can be suppressed. Further, due to the negative pressure generated at the ventilation port, the air outside the electric drive device is taken into the cooling air passage through the intake port, the internal space of the housing, the flow hole, the internal space of the casing, and the ventilation port. Therefore, not only the heat generated in the internal space of the casing but also the heat generated in the internal space of the housing can be discharged through the cooling air passage. Thereby, not only the cooling performance for the control device but also the cooling performance for the rotating electrical machine can be enhanced.

[0021] In the above aspect, the rotating electrical machine further has a lid body (37) that closes the opening of the housing on the side opposite to the control device, and the lid body is provided with an intake port (53) penetrating in the axial direction, and the cooling air passage may communicate with the intake port through the internal space of the housing, the internal space of the casing, and the ventilation port.

[0022] According to this aspect, due to the negative pressure generated at the ventilation port, the air outside the electric drive device is taken into the cooling air passage through the intake port, the internal space of the housing, the internal space of the casing, and the ventilation port. Therefore, not only the heat generated in the internal space of the casing but also the heat generated in the internal space of the housing can be discharged through the cooling air passage. Thereby, not only the cooling performance for the control device but also the cooling performance for the rotating electrical machine can be enhanced.

[0023] In the above aspect, the electric drive device is provided on a moving body (1), and the shaft may extend along the propulsion direction of the moving body.

[0024] According to this aspect, it is possible to promote the introduction of the wind generated along with the propulsion of the moving body from the tip of the shaft into the internal space of the shaft. Therefore, the cooling effect on the control device can be enhanced.

Advantages of the Invention

[0025] According to the above aspect, by sufficiently cooling the inner peripheral portion of the control device, the temperature deviation in the control device can be suppressed.

Brief Description of the Drawings

[0026]

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

Figure 15

Modes for Carrying Out the Invention

[0027] <Aircraft 1> Hereinafter, with reference to the drawings, an aircraft 1 (an example of a moving body) according to an embodiment of the present invention will be described.

[0028] Referring to FIG. 1, the aircraft 1 is an electric vertical takeoff and landing aircraft (eVTOL) that can take off and land vertically. The aircraft 1 includes a fuselage 2 extending in the front-rear direction, a front wing 3 extending in the left-right direction and connected to the front part of the fuselage 2, a rear wing 4 extending in the left-right direction and connected to the rear part of the fuselage 2, a left arm 5L extending in the front-rear direction and connecting the left end of the front wing 3 and the left side of the rear wing 4, and a right arm 5R extending in the front-rear direction and connecting the right end of the front wing 3 and the right side of the rear wing 4.

[0029] A cabin (not shown) for passengers to board is provided at the front part of the fuselage 2. At the rear end of the fuselage 2, left and right propulsion units 7 (details will be described later) for generating a forward propulsion force for the aircraft 1 are provided.

[0030] A plurality (for example, four) of lifting units 10 for generating a lifting force and a descending force for the aircraft 1 are provided at intervals in the front-rear direction on the left arm 5L and the right arm 5R, respectively. Each lifting unit 10 includes a lifting drive device 12 and a lifting propeller 13 attached to the lifting drive device 12. The lifting drive device 12 has an electric motor (not shown), and is configured to rotate the lifting propeller 13 by the driving force of the electric motor.

[0031] <Propulsion Unit 7> Referring to FIG. 2, each propulsion unit 7 includes a support 15, front and rear propulsion drive devices 16 (an example of an electric drive device) supported by the support 15, a rotating shaft 17 extending in the front-rear direction and rotatably supported by the front and rear propulsion drive devices 16, and a propulsion propeller 18 fixed to the rear part of the rotating shaft 17.

[0032] The support body 15 is fixed to the rear end portion of the fuselage 2 (see FIG. 1). The support body 15 has a cylindrical nacelle 20 extending in the front-rear direction and front and rear mount frames 21 fixed to the inner peripheral surface of the nacelle 20. Each mount frame 21 has an annular hub 23 provided concentrically with the nacelle 20 and a plurality of spokes 24 extending radially from the outer peripheral surface of the hub 23 and connected to the inner peripheral surface of the nacelle 20.

[0033] The front and rear propulsion drive devices 16 are housed in the nacelle 20. The front and rear propulsion drive devices 16 are respectively fixed to the front surfaces of the hubs 23 of the front and rear mount frames 21. The details of each propulsion drive device 16 will be described later.

[0034] The rotating shaft 17 is housed in the nacelle 20. The rotating shaft 17 passes through the hubs 23 of each mount frame 21. A conical front cover 26 that expands in diameter rearward is fixed to the front end portion of the rotating shaft 17. The front cover 26 is disposed in front of the front propulsion drive device 16. A conical rear cover 27 that expands in diameter forward is fixed to the rear end portion of the rotating shaft 17. The rear cover 27 is disposed behind the central portion of the propulsion propeller 18.

[0035] The propulsion propeller 18 is housed in the nacelle 20. The propulsion propeller 18 is configured to generate a forward propulsion force for the aircraft 1 by rotating integrally with the rotating shaft 17 as the rotating shaft 17 rotates.

[0036] <Propulsion drive device 16> Referring to FIGS. 2 and 3, each propulsion drive device 16 includes an electric motor 31 (an example of a rotating electric machine), a control device 32 disposed on the rear side of the electric motor 31, a fan 33 disposed on the front side of the electric motor 31, and a duct cover 34 that covers the outer peripheries of the electric motor 31, the control device 32, and the fan 33. In FIG. 4, the duct cover 34 is not shown.

[0037] <Electric motor 31> Referring to FIGS. 4 and 5, the electric motor 31 is sandwiched between the control device 32 and the fan 33. For example, the electric motor 31 is an inner rotor type three-phase AC motor. The electric motor 31 includes a housing 36, a lid 37, a shaft 38, a rotor 39, and a stator 40.

[0038] The housing 36 is cylindrical and extends in the front-rear direction on the outer periphery of the shaft 38. The housing 36 is disposed on the outer periphery of the rotor 39 and the stator 40 and houses the rotor 39 and the stator 40 (an example of a component of the electric motor 31).

[0039] On the outer peripheral surface of the housing 36, a plurality of first cooling fins 42 project at intervals in the circumferential direction of the housing 36. The plurality of first cooling fins 42 are integrally formed with the housing 36. Each first cooling fin 42 is flat and extends along the front-rear direction. Each first cooling fin 42 continuously extends from the front end portion (one end portion in the front-rear direction) to the rear end portion (the other end portion in the front-rear direction) of the housing 36.

[0040] On the outer peripheral surface of the housing 36, a plurality of fastening protrusions 43 project at intervals in the circumferential direction of the housing 36. The plurality of fastening protrusions 43 are provided between adjacent first cooling fins 42. A cooling air flow path P that is continuous from the front end portion to the rear end portion of the housing 36 is formed between adjacent first cooling fins 42 and each fastening protrusion 43. The plurality of fastening protrusions 43 are integrally formed with the housing 36.

[0041] Each fastening protrusion 43 has a rod shape with a rectangular cross section and extends along the front-rear direction. That is, each fastening protrusion 43 extends parallel to each first cooling fin 42. Each fastening protrusion 43 continuously extends from the front end portion (one end portion in the front-rear direction) to the rear end portion (the other end portion in the front-rear direction) of the housing 36. Each fastening protrusion 43 is integrally formed of the same material from the front end portion (one end portion in the front-rear direction) to the rear end portion (the other end portion in the front-rear direction).

[0042] At the front end of each fastening projection 43, a first bolt hole 44 for fastening the lid 37 to the housing 36 is provided. At the rear end of each fastening projection 43, a second bolt hole 45 for fastening the casing 74 of the control device 32, which will be described later, to the housing 36 is provided. The first bolt hole 44 and the second bolt hole 45 extend along the front-rear direction.

[0043] The lid 37 is adjacent to the housing 36 and closes the opening on the front side (opposite side to the control device 32) of the housing 36. The lid 37 has a disc shape and extends along a plane orthogonal to the front-rear direction. The lid 37 is formed separately from the housing 36. In other embodiments, the lid 37 may be integrally formed with the housing 36.

[0044] On the outer peripheral portion of the lid 37, a plurality of first fastening pieces 47 project at intervals in the circumferential direction of the lid 37. A first fastening hole 48 is provided in each first fastening piece 47 in the front-rear direction, and the lid 37 is fastened to the housing 36 by engaging a first fastening bolt 49 passing through the first fastening hole 48 with the first bolt hole 44 of each fastening projection 43 of the housing 36. A circular first through hole 51 is provided in the central portion of the lid 37 in the front-rear direction. A first bearing 52 is attached to the first through hole 51. A plurality of intake ports 53 penetrating in the front-rear direction are provided in the inner peripheral portion (portion between the outer peripheral portion and the central portion) of the lid 37. The plurality of intake ports 53 are provided at intervals in the circumferential direction of the lid 37.

[0045] Referring to FIG. 2, the shaft 38 extends in the front-rear direction (an example of a predetermined axial direction). The shaft 38 forms a part of the rotating shaft 17 of the propulsion unit 7. Therefore, when the shaft 38 rotates, the entire rotating shaft 17 rotates, and the propulsion propeller 18 rotates integrally with the rotating shaft 17. As a result, a forward propulsion force is generated on the aircraft 1, and the aircraft 1 propels forward. The shaft 38 extends along the propulsion direction of the aircraft 1 (see the arrow X in FIG. 2).

[0046] Referring to FIG. 5, the shaft 38 is hollow. The shaft 38 has a main body portion 55 housed in the housing 36, an extension portion 56 extending rearward (toward the control device 32 side) from the main body portion 55, and a protruding portion 57 protruding forward (opposite to the control device 32 side) from the main body portion 55. A plurality of shaft holes 59 penetrating from the inner peripheral surface to the outer peripheral surface are provided in the extension portion 56. The plurality of shaft holes 59 face the internal space of the casing 74. The plurality of shaft holes 59 are provided at intervals in the circumferential direction of the shaft 38. The positions of the plurality of shaft holes 59 in the front-rear direction are the same as each other. In other embodiments, the positions of the plurality of shaft holes 59 in the front-rear direction may be shifted from each other. The plurality of shaft holes 59 are arranged on the front side (motor 31 side) of the central portion C in the front-rear direction of the control device 32. The protruding portion 57 penetrates the first through hole 51 of the lid 37 and extends to the space on the front side of the motor 31. The protruding portion 57 is rotatably supported by the lid 37 via the first bearing 52.

[0047] Referring to FIGS. 4 and 5, the rotor 39 is hollow. The rotor 39 is arranged on the outer periphery of the main body portion 55 of the shaft 38. The rotor 39 has a cylindrical rotor core 61 extending in the front-rear direction, a rotor plate 62 extending in the radial direction and connecting the main body portion 55 of the shaft 38 and the rotor core 61, and a plurality of permanent magnets 63 fixed to the outer peripheral surface of the rotor core 61. The rotor core 61 and the rotor plate 62 are integrally formed with the shaft 38. The rotor plate 62 is provided with a plurality of communication holes 65 penetrating in the front-rear direction.

[0048] The stator 40 is disposed on the outer periphery of the rotor 39 and faces the rotor 39 with a gap therebetween. The stator 40 includes a cylindrical stator core 67 extending in the longitudinal direction, a plurality of teeth 68 protruding from the inner peripheral surface of the stator core 67, a plurality of coils 69 wound around the plurality of teeth 68, and three motor-side terminals 70 (an example of a terminal on the rotating electrical machine side) connected to the plurality of coils 69. The stator core 67 is fixed to the inner peripheral surface of the housing 36. Among the components of the electric motor 31 and the control device 32, the plurality of coils 69 generate the largest amount of heat. Therefore, the amount of heat generated by the electric motor 31 is larger than the amount of heat generated by the control device 32. The three motor-side terminals 70 respectively correspond to the U-phase, V-phase, and W-phase of a three-phase alternating current.

[0049] <control device 32> Referring to FIGS. 3 and 4, the control device 32 is integrated with the electric motor 31 and controls the drive of the electric motor 31. That is, the propulsion drive device 16 of the present embodiment is an electromechanical integrated drive device.

[0050] Referring to FIGS. 6 and 7, the control device 32 includes a casing 74, a resolver 75, a DC input connector 76, three power modules 77, three pressing members 78, a smoothing capacitor 79, three first connection members 80, three second connection members 81, first and second DC bus bars 82 and 83, three AC bus bars 84, three current sensors 85, a communication connector 86, a drive board 87, a control board 88, and a partitioning member 89 (see FIG. ). In FIG. 5, the electronic components E of the control device 32 (for example, three power modules 77, a smoothing capacitor 79, three current sensors 85, a drive board 87, and a control board 88) are omitted, and only the approximate positions of the electronic components E are shown.

[0051] Referring to FIG. 5, the casing 74 is adjacent to the housing 36 of the electric motor 31. The casing 74 is formed of metal and has a bottomed cylindrical shape. The casing 74 houses the electronic components E of the control device 32.

[0052] The casing 74 has a cylindrical peripheral wall portion 93 extending in the front-rear direction on the outer periphery of the extension portion 56 of the shaft 38, and a bottom wall portion 94 closing the opening on the rear side (opposite side to the electric motor 31) of the peripheral wall portion 93. Hereinafter, when describing "circumferential direction" in the description of the components of the control device 32, it indicates the circumferential direction of the peripheral wall portion 93 of the casing 74 (in other words, the circumferential direction centered on the extension portion 56 of the shaft 38), and when describing "radial direction" in the description of the components of the control device 32, it indicates the radial direction of the peripheral wall portion 93 of the casing 74 (in other words, the radial direction centered on the extension portion 56 of the shaft 38).

[0053] Referring to FIGS. 3 and 4, a plurality of second cooling fins 96 protrude from the outer peripheral surface of the peripheral wall portion 93 of the casing 74 at intervals in the circumferential direction. The plurality of second cooling fins 96 are integrally formed with the peripheral wall portion 93. Each second cooling fin 96 has a flat plate shape and extends along the front-rear direction. Each second cooling fin 96 continuously extends from the front end portion (one end portion in the front-rear direction) to the rear end portion (the other end portion in the front-rear direction) of the peripheral wall portion 93.

[0054] Referring to FIGS. 3 and 5, a plurality of second fastening pieces 97 protrude from the front end portion (the end portion on the electric motor 31 side) of the outer peripheral surface of the peripheral wall portion 93 of the casing 74 at intervals in the circumferential direction. Each second fastening piece 97 is provided with a second fastening hole 98 in the front-rear direction, and the casing 74 is fastened to the housing 36 by engaging a second fastening bolt 99 passing through the second fastening hole 98 with the second bolt hole 45 of each fastening protrusion 43 of the housing 36.

[0055] A plurality of third fastening pieces 101 protrude from the rear end portion (the end portion opposite to the electric motor 31) of the outer peripheral surface of the peripheral wall portion 93 of the casing 74 at intervals in the circumferential direction. Each third fastening piece 101 is provided with a third fastening hole 102 in the front-rear direction.

[0056] A plurality of ventilation openings 103 penetrating from the inner peripheral surface to the outer peripheral surface are provided in the peripheral wall portion 93 of the casing 74. The plurality of ventilation openings 103 are provided at intervals in the circumferential direction. The positions of the plurality of ventilation openings 103 in the front-rear direction are the same as each other. In other embodiments, the positions of the plurality of ventilation openings 103 in the front-rear direction may be offset from each other. The plurality of ventilation openings 103 are arranged on the side opposite to the electric motor 31 with the central portion C in the front-rear direction of the control device 32 interposed therebetween. The circumferential position of each ventilation opening 103 coincides with the circumferential position of each second fastening piece 97 and each third fastening piece 101. Each ventilation opening 103 is provided between each second fastening piece 97 and each third fastening piece 101.

[0057] Referring to FIGS. 7 and 8, three pedestal portions 105 project from the inner peripheral surface of the peripheral wall portion 93 of the casing 74 at intervals in the circumferential direction. A pair of fixing protrusions 106 project from both circumferential sides of the inner surface (radially inner surface) of each pedestal portion 105. An engagement recess 107 is provided between the pair of fixing protrusions 106 at the circumferential center of the inner surface of each pedestal portion 105. Two of the three pedestal portions 105 are arranged such that the circumferential position of one fixing protrusion 106 overlaps with the circumferential position of the plurality of second fastening pieces 97, and the other fixing protrusion 106 is arranged such that its circumferential position does not overlap between the plurality of second fastening pieces 97.

[0058] Referring to FIGS. 5 and 6, the bottom wall portion 94 of the casing 74 is in a disc shape and extends along a plane orthogonal to the front-rear direction. The bottom wall portion 94 is formed separately from the peripheral wall portion 93. In other embodiments, the bottom wall portion 94 may be integrally formed with the peripheral wall portion 93.

[0059] A plurality of fourth fastening pieces 109 project from the outer peripheral portion of the bottom wall portion 94 of the casing 74 at intervals in the circumferential direction. A fourth fastening hole 110 is provided in each fourth fastening piece 109 in the front-rear direction, and the bottom wall portion 94 is fastened to the peripheral wall portion 93 by engaging a third fastening bolt 111 passing through the fourth fastening hole 110 with the third fastening hole 102 of each third fastening piece 101 of the peripheral wall portion 93.

[0060] At the center of the bottom wall portion 94 of the casing 74, a circular second through hole 113 is provided in the front-rear direction. A second bearing 114 is attached to the second through hole 113. The extension 56 of the shaft 38 penetrates the second through hole 113. The extension 56 of the shaft 38 is rotatably supported in the second through hole 113 via the second bearing 114. At the lower part of the bottom wall portion 94, a first fitting hole 116 and a second fitting hole 117 are provided in the front-rear direction at intervals in the circumferential direction.

[0061] Referring to FIG. 6, the resolver 75 is fixed to the center of the bottom wall portion 94 of the casing 74. A plurality of detection portions (not shown) for detecting the rotation of the extension 56 of the shaft 38 are provided at intervals in the circumferential direction on the resolver 75.

[0062] Referring to FIG. 9, the DC input connector 76 is connected to a DC power supply device 125 provided outside the propulsion drive device 16. For example, the DC power supply device 125 is constituted by a battery or a generator.

[0063] Referring to FIGS. 3 and 6, the DC input connector 76 is fitted into the first fitting hole 116 of the bottom wall portion 94 of the casing 74 and penetrates the bottom wall portion 94 of the casing 74. A pair of DC input terminals 126 are provided on the front surface (the surface on the side of the electric motor 31) of the DC input connector 76.

[0064] Referring to FIG. 9, the three power modules 77 each include two switching elements 128. That is, the control device 32 includes a total of six switching elements 128. The six switching elements 128 constitute an inverter 130 (an example of a power conversion circuit) that converts DC power (DC current) input from the DC power supply device 125 via a pair of DC lines 129 into AC power (AC current). Each switching element 128 is constituted by a semiconductor element such as an IGBT or a MOSFET. Each switching element 128 is arranged in parallel with a freewheel diode 131.

[0065] Referring to FIGS. 7 and 8, the three power modules 77 are in contact with the inner peripheral surface of the peripheral wall portion 93 of the casing 74 at circumferential intervals. The circumferential positions of the three power modules 77 do not overlap with the circumferential positions of the plurality of second fastening pieces 97 (i.e., the fastening points between the casing 74 and the housing 36), and overlap with the circumferential positions of the plurality of second cooling fins 96. The three power modules 77 are arranged avoiding the uppermost part of the casing 74. Note that the arrow D1 appropriately attached to each figure indicates the direction parallel to the inner surface 77A of each power module 77 (hereinafter referred to as the "first direction D1"). Also, the arrow D2 appropriately attached to each figure indicates the direction orthogonal to the first direction D1 and the inner surface 77A of the power module 77 (hereinafter referred to as the "second direction D2").

[0066] Each power module 77 includes a flat module body 133, an AC module bus bar 134 extending radially inward from the front end portion (one end portion in the front-rear direction) of the module body 133, and a first DC module bus bar 135 and a second DC module bus bar 136 extending radially inward from the rear end portion (the other end portion in the front-rear direction) of the module body 133.

[0067] The three pressing members 78 are arranged at circumferential intervals. Each pressing member 78 includes a rectangular parallelepiped engaging piece 138 and a plurality of protruding pieces 139 protruding from both circumferential sides of the engaging piece 138. The engaging piece 138 is engaged with the engaging recess 107 of each pedestal portion 105 provided on the inner peripheral surface of the peripheral wall portion 93 of the casing 74. The engaging piece 138 sandwiches the module body 133 of each power module 77 between it and the engaging recess 107 of each pedestal portion 105, and presses the module body 133 of each power module 77 against the engaging recess 107 of each pedestal portion 105. An AC insert nut 142 is embedded in the front surface (one side surface in the front-rear direction) of the engaging piece 138, and two DC insert nuts 143 are embedded in the rear surface (the other side surface in the front-rear direction) of the engaging piece 138. Each protruding piece 139 is fixed to each fixing projection 106 of each pedestal portion 105 by a fixing bolt 144.

[0068] Referring to FIG. 9, the smoothing capacitor 79 is connected in parallel with the inverter 130 to the DC power supply device 125. The smoothing capacitor 79 smoothes the DC current input from the DC power supply device 125 to the inverter 130. More specifically, the smoothing capacitor 79 protects the three power modules 77 by smoothing the pulse current (pulse-shaped current caused by the surge voltage) generated in the DC current input from the DC power supply device 125 to the three power modules 77.

[0069] Referring to FIG. 7, the smoothing capacitor 79 is provided at a distance from the inner peripheral surface of the peripheral wall portion 93 of the casing 74. The smoothing capacitor 79 is arranged together with the three power modules 77 in the left semi-circular portion (an example of one semi-circular portion) of the casing 74. The smoothing capacitor 79 is continuously provided along the inner surface 77A of the three power modules 77 (more specifically, the radially inner surface of the module body 133 of the three power modules 77). Therefore, when viewed from the front side (the side of the electric motor 31), between the second through-hole 113 in the bottom wall portion 94 of the casing 74 and the inner peripheral surface of the peripheral wall portion 93 of the casing 74, the smoothing capacitor 79 and each power module 77 are arranged in order from the radially inner side to the outer side.

[0070] Referring to FIG. 10, the smoothing capacitor 79 is arranged at a radial distance from each power module 77. The smoothing capacitor 79 and each power module 77 are arranged on the same plane orthogonal to the front-rear direction. In other words, the position of the smoothing capacitor 79 in the front-rear direction overlaps with the position of each power module 77 in the front-rear direction.

[0071] Referring to FIGS. 7 and 11, the smoothing capacitor 79 includes a plurality of capacitor elements 147 and a capacitor case 148 that houses the plurality of capacitor elements 147. That is, the smoothing capacitor 79 is configured as a capacitor unit in which a plurality of capacitor elements 147 are integrated. The smoothing capacitor 79 is bent so as to protrude toward each power module 77 side (radially outward) when viewed from the front side (the side of the electric motor 31), forming a substantially U shape.

[0072] The capacitor case 148 is filled with a potting agent (not shown). For example, the potting agent is made of an insulating resin. The capacitor case 148 includes a case body 153 and three closing members 154 attached to the case body 153.

[0073] The case body 153 of the capacitor case 148 is made of a metal such as aluminum. The case body 153 has a box shape with an open front surface (a surface on one side in the front-rear direction). A plurality of support protrusions 156 are provided at the front end portion (one end portion in the front-rear direction) of the case body 153. A plurality of mounting protrusions 157 are provided at the rear end portion (the other end portion in the front-rear direction) of the case body 153. Each mounting protrusion 157 is attached to the bottom wall portion 94 of the casing 74 by a mounting bolt 158.

[0074] The case body 153 of the capacitor case 148 includes an inner wall portion 160 (a radially inner wall portion) extending in the circumferential direction, an outer wall portion 161 (a radially outer wall portion) extending in the circumferential direction on the radially outer side of the inner wall portion 160, a pair of side wall portions 162 extending in the radial direction and connecting both circumferential ends of the inner wall portion 160 and both circumferential ends of the outer wall portion 161, and a base wall portion 163 connecting the rear ends (the ends opposite to the electric motor 31) of the inner wall portion 160, the outer wall portion 161, and the pair of side wall portions 162. Three planar portions 165 are formed inside the plurality of capacitor elements 147 in the radial direction on the inner wall portion 160. When viewed from the front side (the side of the electric motor 31), each planar portion 165 extends along the second direction D2. Three case openings 166 are formed outside the plurality of capacitor elements 147 in the radial direction on the outer wall portion 161. The three case openings 166 are arranged at intervals in the circumferential direction. Each case opening 166 has a rectangular shape that is long in the front-rear direction and the first direction D1. Three fitting recesses 167 (see FIG. 10) are formed at positions on the radially outer portion of the base wall portion 163 that face the three case openings 166.

[0075] Referring to FIGS. and, the three closing members 154 of the capacitor case 148 close the three case openings 166 of the case body 153, respectively. Each closing member 154 is made of an insulating resin. Each closing member 154 includes a first closing piece 169 and a second closing piece 170 arranged on the front side (one side in the front-rear direction) of the first closing piece 169.

[0076] Referring to FIGS. and, the first closing piece 169 of each closing member 154 is fitted into each fitting recess 167 of the case body 153. On the front surface (one surface in the front-rear direction) of the first closing piece 169, three partition ribs 172 extending in the second direction D2 and a connecting rib 173 extending in the first direction D1 and connecting the middle portions of the three partition ribs 172 are provided. Two mounting grooves 174 extending in the second direction D2 are provided between the three partition ribs 172 and on the rear side (the other side in the front-rear direction) of the connecting rib 173.

[0077] Referring to FIGS. 10 and 11, the second closing piece 170 of each closing member 154 is formed separately from the first closing piece 169. The second closing piece 170 has a flat rectangular parallelepiped shape that is long in the front-rear direction and the first direction D1. On both sides of the second closing piece 170 in the first direction D1, a pair of first engaging grooves 176 extending in the front-rear direction are formed. The pair of first engaging grooves 176 engage with the outer wall portion 161 of the case body 153 on both sides of each case opening 166 in the first direction D1. The front end portion (one end portion in the front-rear direction) of the second closing piece 170 is provided flush with the front surface (one surface in the front-rear direction) of the outer wall portion 161 of the case body 153. A second engaging groove 177 extending in the first direction D1 is formed at the rear end portion (the other end portion in the front-rear direction) of the second closing piece 170. The second engaging groove 177 engages with the connecting rib 173 of the first closing piece 169.

[0078] Referring to FIGS. 10 and 13, each first connecting member 80 connects each capacitor element 147 and each power module 77. The radially inner end portion of each first connecting member 80 is connected to the upper part of the side surface (the radially outer surface) of each capacitor element 147. Each first connecting member 80 engages with one mounting groove 174 of the first closing piece 169 of each closing member 154. Each first connecting member 80 passes through the rear side of the second closing piece 170 (see FIGS. 10 and 11) of each closing member 154 and extends to the rear side of each power module 77. That is, each first connecting member 80 penetrates each closing member 154.

[0079] Referring to FIGS. 10 and 13, each second connecting member 81 connects each capacitor element 147 and each power module 77. The radially inner end portion of each second connecting member 81 is connected to the lower part of the side surface (the radially outer surface) of each capacitor element 147. Each second connecting member 81 engages with the other mounting groove 174 of the first closing piece 169 of each closing member 154. Each second connecting member 81 passes through the rear side of the second closing piece 170 (see FIGS. 10 and 11) of each closing member 154 and extends to the rear side of each power module 77. That is, each second connecting member 81 penetrates each closing member 154.

[0080] Referring to FIG. 6, the first DC bus bar 82 has a first main body bus bar 199 extending in the circumferential direction and three first auxiliary bus bars 200 bent rearward from the outer peripheral portion of the first main body bus bar 199. One circumferential end portion of the first main body bus bar 199 is connected to one DC input terminal 126 of the DC input connector 76. Referring to FIG. 13, the tip of each first auxiliary bus bar 200 is bent radially outward and extends to the rear side of each pressing member 78. The tip of each first auxiliary bus bar 200, together with the first DC module bus bar 135 of each power module 77 and the radially outer end of each first connecting member 80, is fixed to one DC insert nut 143 of each pressing member 78 by a first fixing bolt 201. Thereby, the first DC bus bar 82, each power module 77, and each first connecting member 80 are connected to each other.

[0081] Referring to FIG. 6, the second DC bus bar 83 has a second main body bus bar 203 extending in the circumferential direction and three second auxiliary bus bars 204 bent rearward from the outer peripheral portion of the second main body bus bar 203. One circumferential end portion of the second main body bus bar 203 is connected to the other DC input terminal 126 of the DC input connector 76. Referring to FIG. 13, the tip of each second auxiliary bus bar 204 is bent radially outward and extends to the rear side of each pressing member 78. The tip of each second auxiliary bus bar 204, together with the second DC module bus bar 136 of each power module 77 and the radially outer end of each second connecting member 81, is fixed to the other DC insert nut 143 of each pressing member 78 by a second fixing bolt 205. Thereby, the second DC bus bar 83, each power module 77, and each second connecting member 81 are connected to each other.

[0082] Referring to FIGS. 6 and 13, one longitudinal end of each AC bus bar 84 is fixed to the AC insert nut 142 of each pressing member 78 by a third fixing bolt 209 together with the AC module bus bar 134 of each power module 77. Thereby, each AC bus bar 84 and each power module 77 are connected to each other. An AC output terminal 211 is provided at the other longitudinal end of each AC bus bar 84. That is, the control device 32 is provided with three AC output terminals 211. The three AC output terminals 211 are arranged at a circumferential interval from a pair of DC input terminals 126 in the right semi-circular portion (an example of the other semi-circular portion) of the casing 74. Each AC output terminal 211 is connected to each motor-side terminal 70 (see FIG. 4) of the stator 40 of the electric motor 31 in the internal space of the casing 74. Thereby, as shown in FIG. 9, the alternating current output from the inverter 130 (three power modules 77) is output to each coil 69 of the electric motor 31 via each AC output terminal 211 and each motor-side terminal 70.

[0083] Referring to FIG. 9, three current sensors 85 are respectively arranged on three AC lines 207 (three-phase lines) from the inverter 130 (three power modules 77) to each coil 69 of the electric motor 31, and detect the values of the currents output from the three power modules 77.

[0084] Referring to FIG. 6, three current sensors 85 are respectively arranged on the three AC bus bars 84. The three current sensors 85 are arranged in the right semi-circular portion of the casing 74. The three current sensors 85 are arranged at a circumferential interval. The three current sensors 85 are fixed to a sensor holder 214 fixed to the outer periphery of the bottom wall portion 94 of the casing 74. The sensor holder 214 is formed separately from the resolver 75.

[0085] The communication connector 86 is arranged circumferentially between a pair of DC input terminals 126 and three AC output terminals 211. The communication connector 86 is fitted into the second fitting hole 117 of the bottom wall portion 94 of the casing 74 and penetrates the bottom wall portion 94 of the casing 74. The communication connector 86 is connected to an external device (for example, a control device provided on the body 2) provided outside the propulsion drive device 16.

[0086] The drive board 87 is a gate drive board for driving the switching elements 128 (semiconductor elements) of the three power modules 77. The drive board 87 is arranged on the front side (the side of the electric motor 31) of the smoothing capacitor 79. The drive board 87 is supported by a plurality of support protrusions 156 provided on the case body 153 of the capacitor case 148 of the smoothing capacitor 79.

[0087] The control board 88 is an ECU board that controls the drive of the inverter 130 (three power modules 77) via the drive board 87. The control board 88 is connected to the drive board 87 via a connector (not shown) and is also connected to the communication connector 86 via a cable (not shown). The control board 88 is held by a holding member (not shown) attached to the bottom wall portion 94 of the casing 74.

[0088] Referring to FIG. 5, the partition member 89 partitions the internal space of the housing 36 and the internal space of the casing 74. The partition member 89 partitions the rotor 39 and the stator 40 of the electric motor 31 and the electronic components E of the control device 32 (for example, three power modules 77, a smoothing capacitor 79, three current sensors 85, a drive board 87, and a control board 88). The partition member 89 is housed in the casing 74. In other embodiments, the partition member 89 may be housed in the housing 36 of the electric motor 31. The partition member 89 has a flat plate shape along a plane orthogonal to the front-rear direction. A shaft hole 216 is provided at the center of the partition member 89. The extension 56 of the shaft 38 passes through the shaft hole 216. A plurality of flow holes 217 penetrating in the front-rear direction are provided in the partition member 89 radially outside the shaft hole 216. The plurality of flow holes 217 are provided at intervals in the circumferential direction.

[0089] <Fan 33> Referring to FIGS. 3 to 5, the fan 33 is disposed on the front side (one side in the front-rear direction) of the electric motor 31. The fan 33 is disposed on the side opposite to the control device 32 with the electric motor 31 interposed therebetween. The fan 33 has a cylindrical hub portion 223 extending in the front-rear direction, a cylindrical rim portion 224 extending in the front-rear direction on the outer periphery of the hub portion 223, and a plurality of spoke portions 225 extending in the radial direction and connecting the hub portion 223 and the rim portion 224. The hub portion 223 is fixed to the protruding portion 57 of the shaft 38 of the electric motor 31. Thereby, the fan 33 can rotate integrally with the shaft 38. A plurality of air blowing ribs 226 are provided on the outer peripheral surface of the rim portion 224 at intervals in the circumferential direction of the rim portion 224. Each air blowing rib 226 is inclined forward (one side in the front-rear direction) toward the downstream side in the rotation direction R of the fan 33.

[0090] <Duct cover 34> Referring to FIGS. 3 and 4, the duct cover 34 has a cylindrical shape extending in the front-rear direction. A cooling air passage 229 is formed between the duct cover 34 and the housing 36 of the electric motor 31 and the peripheral wall portion 93 of the casing 74 of the control device 32. That is, the cooling air passage 229 is formed on the outer periphery of the housing 36 of the electric motor 31 and the casing 74 of the control device 32. The cooling air passage 229 has a cylindrical shape and extends in the front-rear direction. A plurality of ventilation openings 103 of the casing 74 face the cooling air passage 229. Therefore, the cooling air passage 229 communicates with the internal space of the shaft 38 via a plurality of shaft holes 59 in the extension portion 56 of the shaft 38, the internal space of the casing 74, and a plurality of ventilation openings 103 of the casing 74. Further, the cooling air passage 229 communicates with a plurality of intake openings 53 of the lid body 37 via the internal space of the housing 36, a plurality of flow holes 217 of the partition member 89, the internal space of the casing 74, and a plurality of ventilation openings 103 of the casing 74.

[0091] <Cooling of the Electric Motor 31 and the Control Device 32> Referring to FIGS. 3 and 5, when the electric motor 31 is driven and the shaft 38 rotates, the fan 33 fixed to the protruding portion 57 of the shaft 38 rotates integrally with the shaft 38. As a result, as indicated by the arrow X1 in FIG. 5, cooling air is sent toward the outer peripheral surface of the housing 36 and the outer peripheral surface of the peripheral wall portion 93 of the casing 74 by the plurality of air blowing ribs 226 of the fan 33. That is, the cooling air is introduced into the cooling air passage 229 by the plurality of air blowing ribs 226 of the fan 33.

[0092] The cooling air introduced into the cooling air passage 229 flows from the front side to the rear side between the outer periphery of the housing 36 and the plurality of first cooling fins 42. Thereby, the electric motor 31 is cooled by the cooling air. Next, the cooling air flows from the front side to the rear side between the outer periphery of the peripheral wall portion 93 of the casing 74 and the plurality of second cooling fins 96. Thereby, the housing 36 of the control device 32 is cooled by the cooling air. The cooling air that has passed through the outer periphery of the peripheral wall portion 93 of the casing 74 is discharged from the rear end portion of the cooling air passage 229 to the space behind the control device 32.

[0093] When the cooling air passes through the cooling air passage 229 as described above, negative pressure is generated at the plurality of ventilation openings 103 of the casing 74. More specifically, the plurality of ventilation openings 103 of the casing 74 create a negative pressure with respect to the internal space of the shaft 38 and the internal space of the casing 74. Therefore, as indicated by the arrow X2 in FIG. 5, the outside air introduced into the internal space of the shaft 38 from the front end portion of the hollow shaft 38 passes through the plurality of shaft holes 59 of the extension portion 56 of the shaft 38, the internal space of the casing 74, and the plurality of ventilation openings 103 of the casing 74 and is taken into the cooling air passage 229. The air taken into the cooling air passage 229 is discharged from the rear end portion of the cooling air passage 229 to the space behind the control device 32 together with the cooling air flowing through the cooling air passage 229.

[0094] Also, when negative pressure is generated at the plurality of ventilation openings 103 of the casing 74 as described above, as indicated by the arrow X3 in FIG. 5, the outside air is taken into the cooling air passage 229 through the plurality of air intake openings 53 of the lid body 37, the internal space of the housing 36, the plurality of flow holes 217 of the partition member 89, the internal space of the casing 74, and the plurality of ventilation openings 103 of the casing 74. The air taken into the cooling air passage 229 is discharged from the rear end portion of the cooling air passage 229 to the space behind the control device 32 together with the cooling air flowing through the cooling air passage 229.

[0095] In order to efficiently take in the wind generated during the propulsion of the aircraft 1 from the front end portion of the shaft 38, the front cover 26 (see FIG. 2) disposed in front of the propulsion drive device 16 may be provided with a through hole (not shown) for exposing the front end portion of the shaft 38. Further, a filter structure may be provided at the front end portion of the shaft 38 to prevent foreign substances other than air (for example, moisture and dust) from entering the internal space of the shaft 38.

[0096] <Effect> In this embodiment, in an electromechanical drive device, the control device 32 is cooled using a plurality of second cooling fins 96 provided on the outer peripheral surface of the peripheral wall portion 93 of the casing 74. When such a configuration is adopted, the temperature of the outer peripheral portion of the internal space of the casing 74 close to the plurality of second cooling fins 96 tends to decrease, but the temperature of the inner peripheral portion of the internal space of the casing 74 far from the plurality of second cooling fins 96 is difficult to decrease. Therefore, it is difficult to uniformly decrease the ambient temperature of the internal space of the casing 74.

[0097] Therefore, in this embodiment, by utilizing the negative pressure generated at the plurality of ventilation openings 103, the air in the internal space of the shaft 38 is taken into the cooling air passage 229 through the plurality of shaft holes 59 in the extension portion 56 of the shaft 38, the internal space of the casing 74, and the plurality of ventilation openings 103 of the casing 74. As a result, the air in the internal space of the shaft 38 passes through the inner peripheral portion and the outer peripheral portion of the internal space of the casing 74 and flows into the cooling air passage 229, and the inner peripheral portion and the outer peripheral portion of the control device 32 can be effectively cooled.

[0098] In particular, the air in the internal space of the shaft 38 is first introduced into the inner peripheral portion of the internal space of the casing 74. Therefore, the inner peripheral portion of the control device 32 where heat tends to accumulate can be sufficiently cooled, and the temperature deviation in the control device 32 can be suppressed. As a result, the inner peripheral portion and the outer peripheral portion of the control device 32 have approximately the same cooling performance, and it becomes easier to evaluate the cooling performance of the control device 32.

[0099] In addition, since the inner peripheral portion of the control device 32 can be sufficiently cooled as described above, the thermal influence on the electronic components E arranged in the inner peripheral portion of the control device 32 can be suppressed. Therefore, it is not necessary to use a device with high heat resistance as the electronic component E arranged in the inner peripheral portion of the control device 32 in consideration of the above thermal influence, and the selection of the electronic component E arranged in the inner peripheral portion of the control device 32 becomes easier.

[0100] <Modification Example> In the above-described embodiment, the internal space of the housing 36 and the internal space of the casing 74 are partitioned by the partitioning member 89. As shown in FIG. 14, in the first modification of the above-described embodiment, the partitioning member 89 is not provided, and the internal space of the housing 36 and the internal space of the casing 74 communicate with each other entirely. Therefore, the cooling air passage 229 communicates with the plurality of air inlets 53 of the lid body 37 via the internal space of the housing 36, the internal space of the casing 74, and the plurality of ventilation openings 103 of the casing 74.

[0101] In the above-described embodiment, the circumferential position of each ventilation opening 103 coincides with the circumferential positions of each second fastening piece 97 and each third fastening piece 101. As shown in FIG. 15, in the second modification of the above-described embodiment, the circumferential position of each ventilation opening 103 is shifted with respect to the circumferential positions of each second fastening piece 97 and each third fastening piece 101. In this case, an axial passage 229A that extends in the front-rear direction from the front end portion (one end portion in the front-rear direction) to the rear end portion (the other end portion in the front-rear direction) of the peripheral wall portion 93 of the casing 74 is formed along the front-rear direction between the plurality of second cooling fins 96 in the cooling air passage 229, and it is preferable that each ventilation opening 103 is arranged facing this axial passage 229A.

[0102] In the above-described embodiment, the propulsion drive device 16 includes the fan 33. In other embodiments, the propulsion drive device 16 may not include the fan 33. In this case, by omitting the front cover 26 (see FIG. 2) disposed in front of the propulsion drive device 16, the wind generated during the propulsion of the aircraft 1 may be directly introduced into the cooling air passage 229.

[0103] In the above-described embodiment, the inner rotor type electric motor 31 is an example of the rotating electric machine. In other embodiments, an outer rotor type electric motor may be an example of the rotating electric machine, or a generator may be an example of the rotating electric machine.

[0104] In the above-described embodiment, the configuration of the present invention is applied to the propulsion drive device 16. In other embodiments, the configuration of the present invention may be applied to the lifting drive device 12.

[0105] In the above-described embodiment, the configuration of the present invention is applied to an electric vertical takeoff and landing aircraft. In other embodiments, the configuration of the present invention may be applied to an aircraft other than an electric vertical takeoff and landing aircraft (i.e., a general aircraft that cannot take off and land vertically), or to a moving body other than an aircraft (for example, vehicles such as automobiles and motorcycles). Further, in other embodiments, the configuration of the present invention may be applied to a fixedly provided device.

[0106] With the above, the description of the specific embodiments is completed. However, the present invention is not limited to the above embodiments and modification examples, and can be widely modified and implemented.

Explanation of Reference Numerals

[0107] 1: Aircraft (an example of a moving body) 16: Propulsion drive device (an example of an electric drive device) 31: Electric motor (an example of a rotating electric machine) 32: Control device 33: Fan 34: Duct cover 36: Housing 37: Cover 38: Shaft 53: Intake port 55: Main body 56: Extension 57: Protrusion 59: Shaft hole 74: Casing 89: Partition member 103: Ventilation port 217: Flow hole 229: Cooling air passage

Claims

1. An electric drive device comprising a rotating electrical machine and a control device integrated with the rotating electrical machine for controlling the drive of the rotating electrical machine, wherein the rotating electrical machine has a hollow shaft extending in a predetermined axial direction, and a housing extending in the axial direction on the outer periphery of the shaft, and the shaft has a main body portion housed in the housing, and an extension portion extending from the main body portion toward the control device side, and a shaft hole penetrating from the inner peripheral surface to the outer peripheral surface is provided in the extension portion, the control device has a casing extending in the axial direction on the outer periphery of the extension portion, and a ventilation port penetrating from the inner peripheral surface to the outer peripheral surface is provided in the casing, a cooling air passage extending in the axial direction is formed at a position where the ventilation port faces on the outer periphery of the casing, and the cooling air passage communicates with the internal space of the shaft through the shaft hole, the internal space of the casing, and the ventilation port. An electric drive device.

2. The electric drive device according to claim 1, further comprising a fan that rotates integrally with the shaft to introduce cooling air into the cooling air passage.

3. The shaft further has a protruding portion protruding from the main body portion toward the side opposite to the control device, The electric drive device according to claim 2, wherein the fan is disposed on the side opposite to the control device with the rotating electrical machine interposed therebetween and is fixed to the protruding portion.

4. The electric drive device further includes a duct cover that covers the outer peripheries of the rotating electrical machine, the control device, and the fan, The electric drive device according to claim 2, wherein the cooling air passage is formed between the duct cover and the housing and the casing.

5. The shaft hole is disposed closer to the rotating electrical machine side than the central portion in the axial direction of the control device, The electric drive device according to any one of claims 1 to 4, wherein the ventilation port is disposed on the side opposite to the rotating electrical machine with the central portion in the axial direction of the control device interposed therebetween.

6. A plurality of shaft holes are provided at intervals in the circumferential direction of the shaft, The electric drive device according to any one of claims 1 to 4, wherein a plurality of ventilation ports are provided at intervals in the circumferential direction of the casing.

7. The rotating electrical machine further has a lid that closes an opening on the side of the housing opposite to the control device, and an air intake port penetrating in the axial direction is provided in the lid. The rotating electrical machine or the control device is provided with a partitioning member that partitions the internal space of the housing and the internal space of the casing, and the partitioning member is provided with a flow hole that penetrates in the axial direction. The electric drive device according to any one of claims 1 to 4, wherein the cooling air passage communicates with the intake port through the internal space of the housing, the flow hole, the internal space of the casing, and the ventilation port.

8. The rotating electrical machine further includes a lid that closes an opening of the housing on the side opposite to the control device, and the lid is provided with an intake port that penetrates in the axial direction. The electric drive device according to any one of claims 1 to 4, wherein the cooling air passage communicates with the intake port through the internal space of the housing, the internal space of the casing, and the ventilation port.

9. The electric drive device according to any one of claims 1 to 4, which is provided on a moving body and the shaft extends along the propulsion direction of the moving body.

Images