Electric drive device, method for assembling an electric drive device, and wiring structure in an electrical device.

Abstract

By easily securing space for tools to pass through, the work efficiency of the assembly of electric drive devices is improved. [Solution] The electric drive device comprises an electric motor 31 and a control device 32 that controls the electric motor 31. The electric motor 31 comprises a stator 40 and an electrical connection member 41 that is electrically connected to the stator 40. The electrical connection member 41 is fastened to the control device 32, and when the electric drive device is viewed in the axial direction of the electric motor 31, the fastening portion F1 between the electrical connection member 41 and the control device 32 is located inside the electric drive device so as not to overlap with the stator 40.

Description

Technical Field

[0006] , ,

[0001] The present invention relates to an electric drive device, an assembly method of the electric drive device, and a wiring structure in an electric device.

Background Art

[0002] In recent years, efforts to realize a low-carbon society or a decarbonized society have been active, and research and development on electrification technologies have been conducted in vehicles, aircraft, etc. in order to reduce CO2 emissions and improve energy efficiency.

[0003] As one of the research and development on such electrification technologies, research and development on electric drive devices have been conducted. For example, Patent Document 1 discloses a motor device unit (drive device) having a motor device and an inverter device. The motor device has a relay terminal connected to the inverter device.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] As shown in FIG. 3 of Patent Document 1, when viewed in the axial direction of the motor device, the relay terminal is arranged so as to overlap the stator. Therefore, when adopting a configuration in which the relay terminal and the inverter device are fastened along the axial direction of the motor device, it becomes difficult to secure a space for passing a tool for fastening the relay terminal and the inverter device. Accordingly, there is a risk that the workability of the assembly work of the motor device unit will decrease.

[0006] In view of the above background, one aspect of the present invention aims to improve the workability of assembly work for electric drive devices and electrical devices by easily securing space for tools to pass through. This, in turn, contributes to improving energy efficiency. [Means for solving the problem]

[0007] To solve the above problems, one aspect of the present invention provides an electric drive device comprising an electric motor and a control device for controlling the electric motor, wherein the electric motor comprises a stator and an electrical connecting member electrically connected to the stator, the electrical connecting member being fastened to the control device, and when the electric drive device is viewed in the axial direction of the electric motor, the fastening portion between the electrical connecting member and the control device is located inside the electric drive device and does not overlap with the stator.

[0008] Another aspect of the present invention is a method for assembling an electric drive device comprising an electric motor having a stator, a rotor rotatable relative to the stator, and an electrical connection member electrically connected to the stator, and a control device for controlling the electric motor, the method comprising sequentially performing an attachment step of attaching the stator to the control device, a fastening step of fastening the electrical connection member to the control device, and a facing step of facing the rotor toward the stator, wherein in the fastening step, when viewing the electric drive device in the axial direction of the electric motor, the electrical connection member to the control device is fastened toward the inner circumference of the stator, toward the inner circumference of the stator.

[0009] Another aspect of the present invention is a wiring structure in an electrical device, comprising: a cylindrical member extending in the axial direction; an electrical connection member electrically connected to the cylindrical member; and a member to be fastened to the electrical connection member, wherein, when the electrical device is viewed in the axial direction, the fastening portion between the electrical connection member and the member to be fastened is located inside the electrical device and does not overlap with the cylindrical member. [Effects of the Invention]

[0010] According to the above embodiment, the workability of the assembly work of electric drive devices and electrical devices can be improved by easily securing space for tools to pass through. [Brief explanation of the drawing]

[0011] [Figure 1] Perspective view showing an aircraft according to an embodiment [Figure 2] A schematic partial cross-sectional view showing the propulsion unit according to the embodiment. [Figure 3] Perspective view showing a propulsion drive device according to an embodiment. [Figure 4] Exploded perspective view showing a propulsion drive device according to an embodiment. [Figure 5] Cross-sectional view showing a propulsion drive device according to an embodiment. [Figure 6] Front view showing a control device according to an embodiment. [Figure 7] Front view showing a smoothing capacitor and its surrounding area according to an embodiment. [Figure 8] Perspective view showing the fixing structure of the power module according to the embodiment. [Figure 9] Circuit diagram showing a DC power supply and propulsion drive device according to an embodiment. [Figure 10] A perspective cross-sectional view showing a smoothing capacitor and its surrounding area according to an embodiment. [Figure 11] Perspective view showing a smoothing capacitor according to an embodiment. [Figure 12] A perspective view showing the notch and its surrounding area according to the embodiment. [Figure 13] Perspective view showing the electrical connection structure of the control device according to the embodiment. [Figure 14] Cross-sectional view showing the first and second fastening parts and their surrounding areas according to the embodiment. [Figure 15] Front view showing the stator and control device according to the embodiment. [Figure 16] Perspective view showing the installation process according to the embodiment [Figure 17] Perspective view showing the opposing process according to the embodiment

Mode for Carrying Out the Invention

[0012] <Aircraft 1> Hereinafter, referring to the drawings, an aircraft 1 (an example of a moving body) according to an embodiment of the present invention will be described.

[0013] Referring to FIG. 1, the aircraft 1 is an electric vertical take-off and landing aircraft (eVTOL) capable of taking off and landing 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 portion of the fuselage 2, a rear wing 4 extending in the left-right direction and connected to the rear portion of the fuselage 2, a left arm 5L extending in the front-rear direction and connecting the left end portion of the front wing 3 and the left side portion of the rear wing 4, and a right arm 5R extending in the front-rear direction and connecting the right end portion of the front wing 3 and the right side portion of the rear wing 4.

[0014] A cabin (not shown) for passengers to board is provided at the front portion of the fuselage 2. At the rear end portion of the fuselage 2, left and right propulsion units 7 for generating a forward propulsion force for the aircraft 1 are provided.

[0015] 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.

[0016] <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 and an electric 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 portion of the rotating shaft 17.

[0017] The support 15 is fixed to the rear end of the body 2 (see Figure 1). The support 15 has a cylindrical nacelle 20 extending in the front-rear direction and front and rear mounting frames 21 fixed to the inner circumferential surface of the nacelle 20. Each mounting frame 21 has an annular hub 23 provided concentrically with the nacelle 20 and a plurality of spokes 24 extending radially from the outer circumferential surface of the hub 23 and connected to the inner circumferential surface of the nacelle 20.

[0018] The front and rear propulsion drive units 16 are housed in the nacelle 20. Each of the front and rear propulsion drive units 16 is fixed to the front of the hub 23 of the front and rear mounting frames 21, respectively. Details of each propulsion drive unit 16 will be described later.

[0019] The rotating shaft 17 is housed in the nacelle 20. The rotating shaft 17 passes through the hubs 23 of each mounting frame 21. A conical front cover 26, which widens towards the rear, is fixed to the front end of the rotating shaft 17. The front cover 26 is positioned in front of the front propulsion drive unit 16. A conical rear cover 27, which widens towards the front, is fixed to the rear end of the rotating shaft 17. The rear cover 27 is positioned behind the center of the propulsion propeller 18.

[0020] The propulsion propeller 18 is housed in the nacelle 20. The propulsion propeller 18 is configured to rotate integrally with the rotation shaft 17 in conjunction with the rotation of the rotation shaft 17, thereby generating forward thrust for the aircraft 1.

[0021] <Propulsion drive device 16> Referring to Figures 2 and 3, each propulsion drive unit 16 comprises an electric motor 31, a control device 32 located behind the electric motor 31, a fan 33 located in front of the electric motor 31, and a duct cover 34 that covers the outer circumference of the electric motor 31, the control device 32, and the fan 33. Note that the duct cover 34 is not shown in Figure 4.

[0022] <Electric motor 31> Referring to Figures 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 radial gap type three-phase AC motor. The axis Z of the electric motor 31 extends in the front-rear direction. In other words, in this embodiment, the axial direction of the electric motor 31 is the front-rear direction. Hereinafter, the expression "along the front-rear direction" includes not only the meaning of "in a direction parallel to the front-rear direction" but also the meaning of "in a direction slightly inclined with respect to the front-rear direction". The electric motor 31 has a housing 36, a cover 37, a shaft 38, a rotor 39, a stator 40 (an example of a cylindrical member), and three electrical connection members 41.

[0023] The housing 36 is cylindrical and extends in the front-rear direction on the outer circumference of the shaft 38. The housing 36 is positioned on the outer circumference of the rotor 39 and the stator 40 and houses the rotor 39 and the stator 40.

[0024] Multiple first cooling fins 42 protrude from the outer circumferential surface of the housing 36 at intervals in the circumferential direction of the housing 36. The multiple 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 extends continuously from the front end (one end in the front-rear direction) to the rear end (the other end in the front-rear direction) of the housing 36.

[0025] Multiple fastening protrusions 43 protrude from the outer circumferential surface of the housing 36 at intervals in the circumferential direction of the housing 36. The multiple fastening protrusions 43 are provided between adjacent first cooling fins 42. Between adjacent first cooling fins 42 and each fastening protrusion 43, a continuous cooling airflow path P is formed from the front end to the rear end of the housing 36. The multiple fastening protrusions 43 are integrally formed with the housing 36.

[0026] Each fastening projection 43 is rod-shaped with a rectangular cross-section and extends along the front-rear direction. That is, each fastening projection 43 extends parallel to each first cooling fin 42. Each fastening projection 43 extends continuously from the front end (one end in the front-rear direction) to the rear end (the other end in the front-rear direction) of the housing 36. Each fastening projection 43 is integrally formed from the same material from the front end (one end in the front-rear direction) to the rear end (the other end in the front-rear direction).

[0027] Each fastening projection 43 has a first bolt hole 44 at its front end for fastening the cover 37 to the housing 36. Each fastening projection 43 has a second bolt hole 45 at its rear end for fastening the casing 74 of the control device 32 (described later) to the housing 36. The first bolt hole 44 and the second bolt hole 45 extend along the front-rear direction.

[0028] The cover 37 is adjacent to the housing 36 and closes the opening on the front side of the housing 36 (opposite the control device 32). The cover 37 is disc-shaped and extends along a plane perpendicular to the front-rear direction. The cover 37 is formed separately from the housing 36. In other embodiments, the cover 37 may be formed integrally with the housing 36.

[0029] Multiple first fastening pieces 47 protrude from the outer circumference of the cover 37 at intervals in the circumferential direction of the cover 37. Each first fastening piece 47 is provided with a first fastening hole 48 in the front-to-back direction, and the cover 37 is fastened to the housing 36 by a first fastening bolt 49 that passes through the first fastening hole 48 engaging 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 center of the cover 37 in the front-to-back direction. A first bearing 52 is attached to the first through hole 51.

[0030] Referring to Figure 2, the shaft 38 extends in the longitudinal direction. The shaft 38 constitutes 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. This generates a forward thrust for the aircraft 1, causing the aircraft 1 to move forward. The shaft 38 extends along the direction of propulsion of the aircraft 1 (see arrow X in Figure 2).

[0031] Referring to Figure 5, the shaft 38 is hollow. The shaft 38 has a main body 55 housed in the housing 36, an extension 56 extending from the main body 55 toward the rear (towards the control device 32), and a projection 57 protruding from the main body 55 toward the front (opposite side of the control device 32). The projection 57 passes through the first through hole 51 of the cover 37 and extends to the space in front of the electric motor 31. The projection 57 is rotatably supported by the cover 37 via the first bearing 52.

[0032] Referring to Figures 4 and 5, the rotor 39 is hollow. The rotor 39 is rotatably mounted relative to the stator 40. The rotor 39 is positioned on the outer circumference of the main body 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 radially and connecting the main body 55 of the shaft 38 and the rotor core 61, and a plurality of permanent magnets 63 fixed to the outer 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 that penetrate in the front-rear direction.

[0033] The stator 40 is positioned on the outer circumference of the rotor 39 and faces the rotor 39 at a distance. The stator 40 has a cylindrical stator core 67 extending in the front-rear direction, a plurality of teeth 68 protruding from the inner circumferential surface of the stator core 67, and a plurality of coils 69 wound around the plurality of teeth 68. The stator core 67 is fixed to the inner circumferential surface of the housing 36. The plurality of coils 69 generate the most heat among the components of the electric motor 31 and the control device 32. Therefore, the amount of heat generated by the electric motor 31 is greater than the amount of heat generated by the control device 32.

[0034] Referring to Figure 4, the three electrical connection members 41 are provided at intervals in the circumferential direction. The three electrical connection members 41 correspond to the U phase, V phase, and W phase of the three-phase AC, respectively. Each electrical connection member 41 includes a cable 71 that is electrically connected to a plurality of coils 69, and a motor busbar 72 attached to the end of the cable 71.

[0035] <Control device 32> Referring to Figures 3 and 4, the control device 32 is integrated with the electric motor 31 and controls the electric motor 31. In other words, the propulsion drive device 16 in this embodiment is a mechatronic drive device. The control device 32 is electrically connected to the electric motor 31.

[0036] Referring to Figures 6 and 7, the control device 32 includes a casing 74, a resolver 75, a DC input connector 76, three power modules 77 (an example of an electronic component), three pressing members 78, a smoothing capacitor 79, first and second DC busbars 82 and 83, three AC busbars 84, a communication connector 86, a support member 87 (terminal block), three current sensors 88 (an example of a conductive component), three relay busbars 89 (an example of a relay member and a member to be fastened), a drive board 90 (an example of a circuit board), a control board 91 (an example of a circuit board), and a partition member 92 (see Figure 5). Note that in Figure 5, the components E of the control device 32 (for example, three power modules 77, smoothing capacitors 79, three current sensors 88, drive board 90, and control board 91) are omitted, and only the approximate positions of the components E are shown.

[0037] Referring to Figure 5, the casing 74 is adjacent to the housing 36 of the electric motor 31. The casing 74 is made of metal and has a bottomed cylindrical shape. The casing 74 houses the components E of the control device 32.

[0038] The casing 74 has a cylindrical circumferential wall portion 93 extending in the front-rear direction on the outer circumference of the extension portion 56 of the shaft 38, and a bottom wall portion 94 that closes the opening on the rear side (opposite side from the electric motor 31) of the circumferential wall portion 93.Hereinafter, when "circumferential direction" is used in the description of the components of the control device 32, it refers to the circumferential direction of the circumferential wall portion 93 of the casing 74 (in other words, the circular direction centered on the extension portion 56 of the shaft 38), and when "radial direction" is used in the description of the components of the control device 32, it refers to the radial direction of the circumferential wall portion 93 of the casing 74 (in other words, the radial direction centered on the extension portion 56 of the shaft 38).

[0039] Referring to Figures 3 and 4, a plurality of second cooling fins 96 protrude from the outer circumferential 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 is flat and extends along the front-rear direction. Each second cooling fin 96 extends continuously from the front end (one end in the front-rear direction) to the rear end (the other end in the front-rear direction) of the peripheral wall portion 93.

[0040] Referring to Figures 3 and 5, a plurality of second fastening pieces 97 protrude from the front end (the end 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 a second fastening bolt 99 that passes through the second fastening hole 98 engaging with the second bolt hole 45 of each fastening projection 43 of the housing 36.

[0041] Multiple third fastening pieces 101 protrude from the rear end of the outer circumferential surface of the peripheral wall portion 93 of the casing 74 (the end opposite to the electric motor 31) at intervals in the circumferential direction. Each third fastening piece 101 is provided with a third fastening hole 102 in the front-rear direction.

[0042] Referring to Figures 7 and 8, three base portions 105 protrude from the inner circumferential surface of the peripheral wall portion 93 of the casing 74, spaced apart in the circumferential direction. A pair of fixing protrusions 106 protrude from both sides in the circumferential direction of the inner surface (radially inward surface) of each base portion 105. An engagement recess 107 is provided between the pair of fixing protrusions 106 in the circumferential center of the inner surface of each base portion 105.

[0043] Referring to Figures 5 and 6, the bottom wall portion 94 of the casing 74 is disc-shaped and extends along a plane perpendicular to the front-rear direction. The bottom wall portion 94 is formed separately from the circumferential wall portion 93. In other embodiments, the bottom wall portion 94 may be formed integrally with the circumferential wall portion 93.

[0044] Multiple fourth fastening pieces 109 protrude from the outer circumference of the bottom wall portion 94 of the casing 74 at intervals in the circumferential direction. Each fourth fastening piece 109 is provided with a fourth fastening hole 110 in the front-rear direction, and the bottom wall portion 94 is fastened to the circumferential wall portion 93 by engaging a third fastening bolt 111 that passes through the fourth fastening hole 110 with the third fastening hole 102 of each third fastening piece 101 of the circumferential wall portion 93.

[0045] A circular second through-hole 113 is provided in the center of the bottom wall portion 94 of the casing 74, oriented in the front-rear direction. A second bearing 114 is mounted in the second through-hole 113. An extension 56 of the shaft 38 passes through 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. A first fitting hole 116 and a second fitting hole 117 are provided in the front-rear direction, spaced apart in the circumferential direction, at the lower part of the bottom wall portion 94.

[0046] Referring to Figure 6, the resolver 75 is fixed to the center of the bottom wall portion 94 of the casing 74. The resolver 75 is provided with a plurality of detection units (not shown) spaced circumferentially for detecting the rotation of the extension portion 56 of the shaft 38.

[0047] Referring to Figure 9, the DC input connector 76 is connected to a DC power supply unit 125 located outside the propulsion drive unit 16. For example, the DC power supply unit 125 is comprised of a battery or a generator.

[0048] Referring to Figures 3 and 6, the DC input connector 76 is fitted into the first fitting hole 116 of the bottom wall 94 of the casing 74 and penetrates the bottom wall 94 of the casing 74. A pair of DC input terminals 126 are provided on the front surface (the side facing the electric motor 31) of the DC input connector 76.

[0049] Referring to Figure 9, each of the three power modules 77 contains two switching elements 128. In other words, the control device 32 contains 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 125 via a pair of DC lines 129 into AC power (AC current). Each switching element 128 is made up of a semiconductor element such as an IGBT or MOSFET. Each switching element 128 is arranged in parallel with a freewheeling diode 131.

[0050] Each power module 77 is connected to each coil 69 of the stator 40 via each AC busbar 84, each current sensor 88, each intermediate busbar 89, and each electrical connection member 41. As a result, the alternating current output from each power module 77 is output to each coil 69 of the stator 40 via each AC busbar 84, each current sensor 88, each intermediate busbar 89, and each electrical connection member 41.

[0051] Referring to Figures 7 and 8, the three power modules 77 are spaced apart in the circumferential direction and in contact with the inner surface of the circumferential wall portion 93 of the casing 74. The circumferential positions of the three power modules 77 do not overlap with the circumferential positions of the multiple second fastening pieces 97 (i.e., fastening points between the casing 74 and the housing 36), but overlap with the circumferential positions of the multiple second cooling fins 96. The three power modules 77 are arranged to avoid the top of the casing 74. Arrows D1, as appropriate in each figure, indicate a direction parallel to the inner surface 77A of each power module 77 (hereinafter referred to as "first direction D1"). Arrows D2, as appropriate in each figure, indicate a direction perpendicular to both the first direction D1 and the inner surface 77A of the power module 77 (hereinafter referred to as "second direction D2").

[0052] Each power module 77 includes a flat module body 133, an AC module busbar 134 extending radially inward from the front end (one end in the front-rear direction) of the module body 133, and a first DC module busbar 135 and a second DC module busbar 136 extending radially inward from the rear end (the other end in the front-rear direction) of the module body 133.

[0053] The three pressing members 78 are arranged at intervals in the circumferential direction. Each pressing member 78 has a rectangular parallelepiped-shaped engaging piece 138 and a plurality of protruding pieces 139 that project from the engaging piece 138 to both sides in the circumferential direction. The engaging piece 138 engages with the engaging recess 107 of each base portion 105 provided on the inner circumferential 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 itself and the engaging recess 107 of each base portion 105, pressing the module body 133 of each power module 77 against the engaging recess 107 of each base portion 105. An AC insert nut 142 is embedded in the front surface (one side 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 in the front-rear direction) of the engaging piece 138. Each protruding piece 139 is fixed to each fixing projection 106 of each base portion 105 by fixing bolts 144.

[0054] Referring to Figure 9, the smoothing capacitor 79 is connected in parallel with the inverter 130 to the DC power supply 125. The smoothing capacitor 79 smooths the DC current input from the DC power supply 125 to the inverter 130. More specifically, the smoothing capacitor 79 protects the three power modules 77 by smoothing the pulse current (pulsating current caused by surge voltage) that occurs in the DC current input from the DC power supply 125 to the three power modules 77.

[0055] Referring to Figure 7, the smoothing capacitor 79 is provided at a distance from the inner surface of the peripheral wall portion 93 of the casing 74. The smoothing capacitor 79 is located in the left semicircular portion of the casing 74 together with the three power modules 77. 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 (electric motor 31 side), the smoothing capacitor 79 and each power module 77 are arranged sequentially from the radially inner to the outer surface between the second through hole 113 of the bottom wall portion 94 of the casing 74 and the inner surface of the peripheral wall portion 93 of the casing 74.

[0056] Referring to Figures 7, 10, and 11, the smoothing capacitor 79 comprises a plurality of capacitor elements 147, a capacitor case 148 (an example of a case) housing the plurality of capacitor elements 147, a molding material 149 (see Figure 11) filled inside the capacitor case 148 and sealing the plurality of capacitor elements 147, three first busbars 150 connected to the plurality of capacitor elements 147, and three second busbars 151 connected to the plurality of capacitor elements 147. In other words, the smoothing capacitor 79 is a capacitor unit formed by assembling and integrating a plurality of capacitor elements 147.

[0057] Multiple capacitor elements 147 are arranged adjacent to each other. Each capacitor element 147 is cylindrical in shape, with an axis extending in the front-to-back direction. That is, in this embodiment, the axial direction of each capacitor element 147 is the front-to-back direction.

[0058] The capacitor case 148 includes a case body 153 that supports a plurality of capacitor elements 147, three wall bodies 154 formed separately from the case body 153 and attached to the case body 153, and three holders 155 (only one shown in Figure 10) formed separately from the case body 153 and the three wall bodies 154, which hold the first and second busbars 150 and 151.

[0059] The case body 153 of the capacitor case 148 is made of a metal such as aluminum. The front surface (one side in the front-to-back direction) of the case body 153 has a case opening. In other words, the case body 153 is box-shaped with an open front. Multiple support protrusions 156 are provided at the front end (one end in the front-to-back direction) of the case body 153. Multiple mounting protrusions 157 are provided at the rear end (the other end in the front-to-back direction) of the case body 153. Each mounting protrusion 157 is attached to the bottom wall 94 of the casing 74 by a mounting bolt 158.

[0060] The case body 153 has a circumferentially elongated shape. When viewed in the front-to-back direction, the case body 153 is bent so as to be convex radially outward (one side in the width direction of the case body 153), forming a roughly U-shape. The case body 153 has an inner wall portion 160 extending in the circumferential direction, an outer wall portion 161 extending in the circumferential direction on the radially outer side of the inner wall portion 160 (an example of a wall portion on one side in the width direction), a pair of side wall portions 162 extending radially and connecting the circumferential ends of the inner wall portion 160 and the circumferential ends of the outer wall portion 161, and a base wall portion 163 connecting the rear ends (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.

[0061] The inner wall portion 160 of the case body 153 rises vertically from the base wall portion 163. Three planar portions 165 are formed on the inner wall portion 160, radially inward of the multiple capacitor elements 147. That is, the three planar portions 165 are provided at positions corresponding to the multiple capacitor elements 147. When viewed from the front side (electric motor 31 side), each planar portion 165 extends along the second direction D2.

[0062] The outer wall portion 161 of the case body 153 rises vertically from the base wall portion 163. Three notches 166 are formed in the outer wall portion 161 on the radially outer side of the multiple capacitor elements 147. That is, the three notches 166 are provided at positions corresponding to the multiple capacitor elements 147. The three notches 166 are spaced apart in the circumferential direction (longitudinal direction of the case body 153). Referring to Figures 10 and 12, each notch 166 has a long rectangular shape in the front-rear direction and in the first direction D1. Each notch 166 penetrates the outer wall portion 161 radially (width direction of the case body 153). Each notch 166 is continuous from the front end (one end in the front-rear direction) to the rear end (the other end in the front-rear direction) of the outer wall portion 161. Each notch 166 has a pair of side edges 167 extending in the front-rear direction and a bottom edge 168 extending in the first direction D1 and connecting the rear ends of the pair of side edges 167. The pair of side edges 167 are spaced apart and face each other in the first direction D1.

[0063] Referring to Figure 7, the base wall portion 163 of the case body 153 has a shape that is elongated in the circumferential direction. Multiple capacitor elements 147 are mounted on the front surface of the base wall portion 163. The rear surface of the base wall portion 163 is in contact with the front surface (cooling surface) of the bottom wall portion 94 of the casing 74.

[0064] Referring to Figures 10 and 11, the three walls 154 of the capacitor case 148 are attached to the outer wall portion 161 of the case body 153. The three walls 154, together with the inner wall portion 160, the outer wall portion 161, and the pair of side walls 162 of the case body 153, define the outer shell of the capacitor case 148 (the portion surrounding the multiple capacitor elements 147 and the molding material 149). The three walls 154 are positioned radially outward from the multiple capacitor elements 147. That is, the three walls 154 are provided in positions corresponding to the multiple capacitor elements 147.

[0065] Each wall 154 is a flattened rectangular parallelepiped that is elongated in the front-rear direction and in the first direction D1. That is, each wall 154 has a shape that corresponds to each notch 166 of the case body 153. Each wall 154 engages with each notch 166 of the case body 153. Each wall 154 is made of insulating resin.

[0066] Each wall 154 includes a pair of side portions 170 extending in the front-rear direction, a bottom portion 171 extending in a first direction D1 and connecting the rear ends of the pair of side portions 170, and a top portion 172 extending in the first direction D1 and connecting the front ends of the pair of side portions 170. Each side portion 170 is provided with a first engagement groove 170A along the front-rear direction. The first engagement groove 170A engages with each side edge 167 of each notch 166 of the case body 153. The bottom portion 171 is provided with a second engagement groove 171A along the first direction D1. A gap G is provided between the bottom portion 171 and the bottom edge 168 of each notch 166 of the case body 153. The top portion 172 is provided flush with the front surface (one side in the front-rear direction) of the outer wall portion 161 of the case body 153.

[0067] Referring to Figures 10 and 12, the three retainers 155 (only one is shown in Figures 10 and 12) of the capacitor case 148 are attached to the outer wall portion 161 and the base wall portion 163 of the case body 153. Each retainer 155 engages with each notch 166 of the case body 153 on the rear side of each wall portion 154. Each retainer 155 fills the entire gap G and surrounds the portion of the first and second busbars 150 and 151 that penetrates the gap G. In other embodiments, each retainer 155 may fill only a portion of the gap G. Each retainer 155 is made of insulating resin.

[0068] Each retainer 155 has a flat base plate 173, a plurality of first ribs 174 protruding from the front surface (one side) of the base plate 173, and a second rib 175 that is spaced apart from and opposite to the front surface of the base plate 173. The base plate 173 has an elongated shape in the first direction D1 and the second direction D2. The plurality of first ribs 174 are spaced apart in the first direction D1 and extend in the second direction D2. A plurality of retaining grooves 176 are formed on the front surface of the base plate 173 between the plurality of first ribs 174. The second rib 175 extends in the first direction D1 and connects the central portions of the plurality of first ribs 174 in the second direction D2. The second rib 175 engages with a second engagement groove 171A of the bottom portion 171 of each wall 154.

[0069] Referring to Figure 11, the molding material 149 is made of, for example, an insulating resin. The molding material 149 covers the entirety of the multiple capacitor elements 147.

[0070] Referring to Figures 12 and 13, the three first busbars 150 and the three second busbars 151 (each shown only once in Figures 12 and 13) are positioned to correspond to the multiple capacitor elements 147. One of the three first busbars 150 and one of the three second busbars 151 are clustered together at positions corresponding to the various notches 166 of the case body 153.

[0071] Referring to Figures 10 and 13, each first busbar 150 connects each capacitor element 147 to each power module 77. The radially inner end of each first busbar 150 is connected to the upper part of the side surface (radially outer surface) of each capacitor element 147. Each first busbar 150 is held in each retaining groove 176 of each retainer 155 of the capacitor case 148. Each first busbar 150 extends through the gap G (see Figure 10) to the rear side of each pressing member 78. The portion of each first busbar 150 that penetrates the gap G is surrounded by the base plate 173, a plurality of first ribs 174, and second ribs 175 of each retainer 155.

[0072] Referring to Figures 10 and 13, each second busbar 151 connects each capacitor element 147 to each power module 77. The radially inner end of each second busbar 151 is connected to the lower part of the side surface (radially outer surface) of each capacitor element 147. Each second busbar 151 is held in each retaining groove 176 of each retainer 155 of the capacitor case 148. Each second busbar 151 extends through the gap G (see Figure 10) to the rear side of each pressing member 78. The portion of each second busbar 151 that penetrates the gap G is surrounded by the base plate 173, a plurality of first ribs 174, and second ribs 175 of each retainer 155.

[0073] Referring to Figure 6, the first DC busbar 82 has a first main busbar 199 extending in the circumferential direction and three first auxiliary busbars 200 that are bent toward the rear from the outer circumference of the first main busbar 199. One circumferential end of the first main busbar 199 is connected to one DC input terminal 126 of the DC input connector 76. Referring to Figure 13, the tip of each first auxiliary busbar 200 is bent radially outward and extends to the rear of each pressing member 78. The tip of each first auxiliary busbar 200, together with the radially outward ends of the first DC module busbar 135 and each first busbar 150 of each power module 77, is fixed to one DC insert nut 143 of each pressing member 78 by a first fixing bolt 201. In this way, the first DC busbar 82, each power module 77, and each first busbar 150 are connected to each other.

[0074] Referring to Figure 6, the second DC busbar 83 has a second main busbar 203 extending in the circumferential direction and three second auxiliary busbars 204 that are bent toward the rear from the outer circumference of the second main busbar 203. One circumferential end of the second main busbar 203 is connected to the other DC input terminal 126 of the DC input connector 76. Referring to Figure 13, the tip of each second auxiliary busbar 204 is bent radially outward and extends to the rear of each pressing member 78. The tip of each second auxiliary busbar 204, together with the radially outward ends of the second DC module busbar 136 and each second busbar 151 of each power module 77, is fixed to the other DC insert nut 143 of each pressing member 78 by a second fixing bolt 205. In this way, the second DC busbar 83, each power module 77, and each second busbar 151 are connected to each other.

[0075] Referring to Figures 6 and 13, one longitudinal end of each AC busbar 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 busbar 134 of each power module 77. This electrically connects each AC busbar 84 to each power module 77.

[0076] 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 fuselage 2) located outside the propulsion drive unit 16.

[0077] Referring to Figures 6 and 14, the support member 87 is fixed to the front surface of the bottom wall portion 94 of the casing 74. The support member 87 is a single molded product made of metal or resin. The support member 87 is formed separately from the resolver 75. Three first fastening members 213 and three second fastening members 214 (only one of each is shown in Figure 14) are embedded in the front surface of the support member 87. Each second fastening member 214 is positioned behind each first fastening member 213 (opposite side from the electric motor 31) and radially outward.

[0078] Referring to Figure 6, the three current sensors 88 are clustered in the right-hand semicircular portion of the casing 74 (an example of one semicircular portion). The three current sensors 88 are spaced apart in the circumferential direction. The three current sensors 88 are supported on the outer circumference of the support member 87. Each current sensor 88 is electrically connected to each power module 77 via each AC busbar 84 and detects the value of the current output from each power module 77.

[0079] Each current sensor 88 comprises a sensor body 216, a first sensor busbar 217 extending upward from the sensor body 216, and a second sensor busbar 218 extending downward from the sensor body 216. The first sensor busbar 217 is fixed to the front surface of the support member 87 via a fourth fastening bolt 219, together with the other longitudinal end of each AC busbar 84. This electrically connects each current sensor 88 to each AC busbar 84.

[0080] Referring to Figures 14 and 15, the three relay busbars 89 are arranged along the front surface of the support member 87. Each relay busbar 89 comprises a first relay piece 221, a second relay piece 222 positioned behind the first relay piece 221 (on the opposite side from the electric motor 31) and radially outward, and a connecting piece 223 extending in the front-rear direction to connect the first relay piece 221 and the second relay piece 222.

[0081] The first relay piece 221 of each relay busbar 89 is fastened to each first fastening member 213 via a first bolt 225 (an example of a first fastening means) together with the motor busbar 72 of each electrical connection member 41. As a result, each electrical connection member 41 and each relay busbar 89 are fastened via the first bolt 225, and each electrical connection member 41 and each relay busbar 89 are electrically connected. The first bolt 225 is arranged along the front-rear direction and fastens each electrical connection member 41 and each relay busbar 89 along the front-rear direction.

[0082] Hereinafter, the fastening portion between each electrical connection member 41 and each relay busbar 89 will be referred to as the "first fastening portion F1". In this embodiment, the propulsion drive unit 16 is provided with three first fastening portions F1. The three first fastening portions F1 are arranged adjacent to the three current sensors 88. When the propulsion drive unit 16 is viewed in the longitudinal direction, all three first fastening portions F1 are located inside the casing 74, not overlapping with the stator 40. More specifically, when the propulsion drive unit 16 is viewed in the longitudinal direction, all three first fastening portions F1 are located on the inner side of the inner circumferential surface 40A of the stator 40, and are concentrated in the semicircular portion to the right of the control device 32. When the propulsion drive unit 16 is viewed in the longitudinal direction, the three first fastening portions F1 are arranged so as not to overlap with the drive board 90 and the control board 91.

[0083] The second relay piece 222 of each relay busbar 89 is fastened to each second fastening member 214 via a second bolt 226 (an example of a second fastening means) together with the second sensor busbar 218 of each current sensor 88. As a result, each current sensor 88 and each relay busbar 89 are fastened to each other via the second bolt 226, and each current sensor 88 and each relay busbar 89 are electrically connected. The second bolt 226 is arranged along the front-rear direction and fastens each current sensor 88 and each relay busbar 89 along the front-rear direction.

[0084] Hereinafter, the fastening portion between each current sensor 88 and each relay busbar 89 will be referred to as the "second fastening portion F2". In this embodiment, the propulsion drive unit 16 is provided with three second fastening portions F2. The three second fastening portions F2 are provided adjacent to the three current sensors 88. When the propulsion drive unit 16 is viewed along the longitudinal direction, two of the three second fastening portions F2 are located inside the casing 74, not overlapping with the stator 40. When the propulsion drive unit 16 is viewed along the longitudinal direction, one of the three second fastening portions F2 is located so as to partially overlap with the stator 40. In other embodiments, when the propulsion drive unit 16 is viewed along the longitudinal direction, all three second fastening portions F2 may be located inside the casing 74, not overlapping with the stator 40, or all three second fastening portions F2 may overlap with the stator 40. Each second fastening portion F2 is positioned behind each first fastening portion F1 (on the opposite side from the electric motor 31) and radially outward. In other words, each second fastening portion F2 is located in a different position from each first fastening portion F1.

[0085] Referring to Figures 6 and 15, the drive board 90 is a gate drive board for driving each switching element 128 (see Figure 9) of the three power modules 77. The drive board 90 is electrically connected to the three power modules 77. The drive board 90 is located in front of the smoothing capacitor 79 (on the electric motor 31 side). The drive board 90 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. When viewing the propulsion drive device 16 in the front-rear direction, the drive board 90 is positioned so as not to overlap with the three first fastening parts F1 and the three second fastening parts F2.

[0086] The control board 91 is an ECU board that controls the drive of the inverter 130 (three power modules 77) via the drive board 90. The control board 91 is electrically connected to the three power modules 77 via the drive board 90. The control board 91 is connected to the drive board 90 via a board connector 229 and also to a communication connector 86 via a cable (not shown). The control board 91 is held in place by a retaining member (not shown) attached to the bottom wall 94 of the casing 74. When viewing the propulsion drive device 16 in the longitudinal direction, the control board 91 is positioned so as not to overlap with the three first fastening parts F1 and the three second fastening parts F2.

[0087] Referring to Figures 5 and 14, the partition member 92 separates the internal space of the housing 36 from the internal space of the casing 74. The partition member 92 separates the rotor 39 and stator 40 of the electric motor 31 from the components E of the control device 32 (for example, three power modules 77, a smoothing capacitor 79, three current sensors 88, a drive board 90, and a control board 91). The partition member 92 is housed in the casing 74. In other embodiments, the partition member 92 may be housed in the housing 36.

[0088] A shaft hole 227 is provided in the center of the partition member 92. The extension 56 of the shaft 38 passes through the shaft hole 227. Through holes 228 are provided on the outer circumference of the partition member 92, running in the front-rear direction. When the propulsion drive device 16 is viewed in the front-rear direction, the through holes 228 are provided so as to overlap with the three first fastening parts F1.

[0089] <Fan 33> Referring to Figures 3 to 5, the fan 33 is positioned in front of the electric motor 31 (on one side in the front-rear direction). The fan 33 is positioned on the opposite side of the electric motor 31 from the control device 32. The fan 33 has a cylindrical hub portion 233 extending in the front-rear direction, a cylindrical rim portion 234 extending in the front-rear direction on the outer circumference of the hub portion 233, and a plurality of spoke portions 235 extending radially and connecting the hub portion 233 and the rim portion 234. The hub portion 233 is fixed to a protruding portion 57 of the shaft 38 of the electric motor 31. This allows the fan 33 to rotate integrally with the shaft 38. A plurality of air-blowing ribs 236 are provided on the outer surface of the rim portion 234 at intervals in the circumferential direction of the rim portion 234. Each air-blowing rib 236 is inclined forward (on 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 Figures 3 and 4, the duct cover 34 is cylindrical in shape and extends in the front-rear direction. A cooling air passage 239 is formed between the duct cover 34 and the peripheral wall portion 93 of the housing 36 of the electric motor 31 and the casing 74 of the control device 32. That is, the cooling air passage 239 is formed on the outer circumference of the housing 36 of the electric motor 31 and the casing 74 of the control device 32. The cooling air passage 239 is cylindrical and extends in the front-rear direction.

[0091] <Assembly work of the propulsion drive unit 16> Next, the assembly process of the propulsion drive unit 16 configured as described above will be explained. In the assembly process of the propulsion drive unit 16, the worker sequentially performs the initial process, the mounting process, the fastening process, the opposing process, and the final process. In other embodiments, an assembly device equipped with a computer may perform some or all of the above-mentioned processes instead of the worker.

[0092] Referring to Figures 6 and 14, in the initial step, the worker fastens each current sensor 88 and each relay busbar 89, which are supported on the outer circumference of the support member 87. More specifically, the worker positions a second bolt 226 along the front-rear direction and fastens the second sensor busbar 218 of each current sensor 88 and the second relay piece 222 of each relay busbar 89 along the front-rear direction using the second bolt 226. Furthermore, the worker houses the partition member 92 in the casing 74 of the control device 32.

[0093] Referring to Figure 16, in the installation process, the worker attaches the housing 36 and stator 40 of the electric motor 31 to the casing 74 of the control device 32. More specifically, with the stator 40 fixed to the housing 36, the worker fastens each second fastening piece 97 of the casing 74 to each fastening projection 43 of the housing 36 using second fastening bolts 99.

[0094] Referring to Figure 14, in the fastening process, when the worker views the propulsion drive unit 16 in the front-rear direction, the worker fastens each electrical connection member 41 to each intermediate bus bar 89 on the inner side of the inner circumferential surface 40A of the stator 40. More specifically, the worker positions the first bolt 225 along the front-rear direction and tightens the first bolt 225 with a tool T that has passed through the inner diameter side (inner circumferential side) of the stator 40, thereby fastening the motor bus bar 72 of each electrical connection member 41 to the first intermediate piece 221 of each intermediate bus bar 89 along the front-rear direction with the first bolt 225.

[0095] Referring to Figure 17, in the opposing process, the operator positions the rotor 39 radially opposite the stator 40. More specifically, the operator inserts the rotor 39 into the space on the inner circumference side of the stator 40, as indicated by arrow Y in Figure 17.

[0096] Referring to Figure 5, in the final step, the worker attaches the cover 37 of the electric motor 31 to the housing 36 of the electric motor 31. More specifically, the worker fastens each fastening projection 43 of the housing 36 to each first fastening piece 47 of the cover 37 using first fastening bolts 49. Furthermore, the worker fixes the fan 33 to the shaft 38 of the electric motor 31 and attaches the duct cover 34 to the outer circumference of the electric motor 31, the control device 32, and the fan 33.

[0097] <Effects> In the above embodiment, when viewing the propulsion drive unit 16 in the longitudinal direction, all three first fastening parts F1 are located inside the casing 74, which does not overlap with the stator 40. This makes it easy to secure space for the tool T that fastens each electrical connection member 41 to each relay bus bar 89 to pass through. Therefore, the workability of assembling the propulsion drive unit 16 is improved. Furthermore, since the electrical connections at the three first fastening parts F1 can be visually confirmed, the reliability of the electrical connections at the three first fastening parts F1 is improved.

[0098] Furthermore, if the first fastening portion F1 is located on the outer circumference of the housing 36 or casing 74, the first and second cooling fins 42 and 96 cannot be placed around the first fastening portion F1. As a result, the number of first and second cooling fins 42 and 96 is reduced, which may lead to a decrease in cooling performance for the electric motor 31 and control device 32. In contrast, in the above embodiment, since the first fastening portion F1 is located inside the casing 74, there is no need to reduce the number of first and second cooling fins 42 and 96. Therefore, a decrease in cooling performance for the electric motor 31 and control device 32 can be suppressed. The same effect is also observed for the second fastening portion F2.

[0099] Furthermore, if the first fastening portion F1 is exposed to the outside of the propulsion drive unit 16, a cover is required to protect the first fastening portion F1. Adding such a cover may increase the number of parts in the propulsion drive unit 16, make the propulsion drive unit 16 heavier, or increase its size. In contrast, in the above embodiment, since the first fastening portion F1 is located inside the casing 74, a cover to cover the first fastening portion F1 is unnecessary. Therefore, the number of parts in the propulsion drive unit 16 can be reduced, making the propulsion drive unit 16 lighter and smaller. The same effect is also observed with respect to the second fastening portion F2.

[0100] Furthermore, if the fastening direction of the first bolt 225 and the fastening direction of the second bolt 226 are opposite, the heads of the first bolt 225 and the second bolt 226 will be facing each other, which may reduce the workability of assembling the propulsion drive unit 16. In contrast, in the above embodiment, the fastening direction of the first bolt 225 (from front to rear) and the fastening direction of the second bolt 226 (from front to rear) are the same. Therefore, the workability of assembling the propulsion drive unit 16 is further improved.

[0101] <Other variations> In the above embodiment, the relay busbar 89 is fastened to the current sensor 88 via the second bolt 226. In other embodiments, the relay busbar 89 may be fastened to the AC busbar 84 or the power module 77 via the second bolt 226. In other words, in the above embodiment, the current sensor 88 is used as the conductive member, but in other embodiments, the AC busbar 84 or the power module 77 may be used as the conductive member.

[0102] In the above embodiment, a relay busbar 89 is used as the relay member. In other embodiments, a member other than a busbar (for example, a cable) may be used as the relay member.

[0103] In the above embodiment, the electrical connection member 41 is electrically connected to the current sensor 88 via the relay bus bar 89. In other embodiments, the electrical connection member 41 may be directly connected to the current sensor 88 or the AC bus bar 84 without going through the relay bus bar 89. In other embodiments, the relay bus bar 89 may be omitted.

[0104] In the above embodiment, the electrical connection member 41 is composed of a cable 71 and a motor busbar 72. In other embodiments, the entire electrical connection member 41 may be composed of only one of either the cable 71 or the motor busbar 72, or the electrical connection member 41 may be composed of members other than the cable 71 or the motor busbar 72.

[0105] In the above embodiment, both the first and second fastening portions F1 and F2 are located inside the casing 74 of the control device 32. In other embodiments, at least one of the first and second fastening portions F1 and F2 may be located inside the housing 36 of the electric motor 31.

[0106] In the above embodiment, an inner rotor radial gap type electric motor 31 is used. In other embodiments, an outer rotor type electric motor or an axial gap type electric motor may be used.

[0107] In the above 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.

[0108] In the above 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 aircraft other than electric vertical takeoff and landing aircraft (i.e., general aircraft that cannot take off or land vertically), or to mobile bodies other than aircraft (for example, automobiles, motorcycles, and other vehicles). Furthermore, in other embodiments, the configuration of the present invention may be applied to a fixedly installed device.

[0109] This concludes the description of specific embodiments, but the present invention is not limited to the above embodiments or modifications and can be broadly modified and implemented.

[0110] <Summary of Embodiments> In the following, the expression "along the axis" includes not only the meaning of "parallel to the axis," but also the meaning of "slightly inclined relative to the axis."

[0111] The electric drive unit 16 comprises an electric motor 31 and a control device 32 that controls the electric motor 31. The electric motor 31 comprises a stator 40 and an electrical connection member 41 that is electrically connected to the stator 40. The electrical connection member 41 is fastened to the control device 32, and when the electric drive unit 16 is viewed in the axial direction of the electric motor 31, the fastening portion F1 between the electrical connection member 41 and the control device 32 is located inside the electric drive unit 16 and does not overlap with the stator 40.

[0112] According to this embodiment, space can be easily secured for the tool T that fastens the electrical connection member 41 and the control device 32 to pass through. Therefore, the workability of the assembly work of the electric drive device 16 is improved.

[0113] The control device 32 includes a conductive member 88 and an intermediate member 89 that is fastened to the electrical connection member 41 at the fastening portion F1 via a first fastening means 225, and fastened to the conductive member 88 at a second fastening portion F2 located at a different position from the fastening portion F1 via a second fastening means 226. The first fastening means 225 is arranged along the axial direction of the electric motor 31 and fastens the electrical connection member 41 and the intermediate member 89 along the axial direction of the electric motor 31. The second fastening means 226 is arranged along the axial direction of the electric motor 31 and fastens the conductive member 88 and the intermediate member 89 along the axial direction of the electric motor 31.

[0114] According to this embodiment, the workability of the assembly of the electric drive device 16 is further improved by aligning the arrangement direction and fastening direction of the first and second fastening means 225 and 226. In addition, by fastening the electrical connection member 41 and the conductive member 88 and the intermediate member 89 via the first and second fastening means 225 and 226, the inspection of the electrical connections of these members becomes easier compared to when these members are fixed by crimping or welding. Furthermore, by fastening the electrical connection member 41 and the conductive member 88 and the intermediate member 89 via the first and second fastening means 225 and 226, the reliability of the electrical connections of these members is improved compared to when these members are fixed by a plug-in structure.

[0115] When viewing the electric drive device 16 in the axial direction of the electric motor 31, the fastening portion F1 between the electrical connection member 41 and the control device 32 is positioned on the inner side of the inner surface 40A of the stator 40.

[0116] According to this embodiment, the electric drive unit 16 can be made smaller compared to the case where the fastening portion F1 is located on the outer circumference of the stator 40. In addition, since the fastening portion F1 is easier to see, the workability of assembly and inspection work of the electric drive unit 16 is improved.

[0117] The control device 32 comprises an electronic component 77 and circuit boards 90 and 91 electrically connected to the electronic component 77. When the electric drive device 16 is viewed in the axial direction of the electric motor 31, the circuit boards 90 and 91 are arranged so as not to overlap with the fastening portion F1 between the electrical connection member 41 and the control device 32.

[0118] According to this embodiment, it is possible to secure space for the tool T that fastens the electrical connection member 41 and the control device 32 to pass through without removing the circuit boards 90 and 91. Therefore, the workability of the assembly work of the electric drive device 16 is further improved.

[0119] Multiple electrical connection members 41 are provided, and when the electric drive device 16 is viewed in the axial direction of the electric motor 31, all of the multiple fastening portions F1 between the multiple electrical connection members 41 and the control device 32 are located on the inner side of the inner circumferential surface 40A of the stator 40 and are concentrated in one semicircular portion of the control device 32.

[0120] According to this embodiment, by grouping the multiple fastening parts F1 into one semicircular portion of the control device 32, a large space for arranging the circuit boards 90 and 91 can be secured in the other semicircular portion of the control device 32. Therefore, the degree of freedom in the shape and arrangement of the circuit boards 90 and 91 is improved. Furthermore, the members supporting the multiple fastening parts F1 can be integrated, thereby reducing their weight.

[0121] The control device 32 comprises an electronic component 77 and a current sensor 88 that detects the value of the current output from the electronic component 77, and the fastening portion F1 between the electrical connection member 41 and the control device 32 is arranged adjacent to the current sensor 88.

[0122] According to this embodiment, the electrical resistance of the connection portion between the current sensor 88 and the fastening portion F1 can be reduced by shortening the length of the connection portion. In addition, by combining the current sensor 88 and the fastening portion F1 in a narrow space, a wider space can be secured for arranging other components. Therefore, the degree of freedom in the layout of other components is improved.

[0123] The device further includes a partitioning member 92 that separates the internal space of the electric motor 31 from the internal space of the control device 32. The partitioning member 92 is provided with a through hole 228 along the axial direction of the electric motor 31, and when the electric drive device 16 is viewed in the axial direction of the electric motor 31, the through hole 228 is positioned to overlap with the fastening portion F1 between the electrical connection member 41 and the control device 32.

[0124] According to this embodiment, it is possible to secure space for the tool T that fastens the electrical connection member 41 and the control device 32 to pass through without removing the partition member 92. Therefore, the workability of the assembly work of the electric drive device 16 is improved.

[0125] A method for assembling an electric drive device 16 comprising an electric motor 31 having a stator 40, a rotor 39 rotatable relative to the stator 40, and an electrical connection member 41 electrically connected to the stator 40, and a control device 32 for controlling the electric motor 31, wherein the assembly method sequentially performs the following steps: an attachment step of attaching the stator 40 to the control device 32; a fastening step of fastening the electrical connection member 41 to the control device 32; and an opposing step of facing the rotor 39 toward the stator 40, wherein in the fastening step, when viewing the electric drive device 16 in the axial direction of the electric motor 31, the electrical connection member 41 to the control device 32 is fastened toward the inner circumference side of the inner circumference surface 40A of the stator 40.

[0126] According to this embodiment, space can be easily secured for the tool T to pass through to fasten the electrical connection member 41 and the control device 32. Therefore, the workability of the assembly work of the electric drive unit 16 is improved. In addition, the electric drive unit 16 can be made smaller compared to the case in which the electrical connection member 41 and the control device 32 are fastened on the outer circumference side of the stator 40.

[0127] The control device 32 includes a conductive member 88 and an intermediate member 89 fastened to the electrical connection member 41 and the conductive member 88. In the fastening step, a first fastening means 225 is positioned along the axial direction of the electric motor 31, and the electrical connection member 41 and the intermediate member 89 are fastened together along the axial direction of the electric motor 31 by the first fastening means 225. Before the mounting step, a second fastening means 226 is positioned along the axial direction of the electric motor 31, and the conductive member 88 and the intermediate member 89 are fastened together along the axial direction of the electric motor 31 by the second fastening means 226.

[0128] According to this embodiment, the workability of the assembly of the electric drive device 16 is further improved by aligning the arrangement direction and fastening direction of the first and second fastening means 225 and 226. In addition, by fastening the electrical connection member 41 and the conductive member 88 and the intermediate member 89 via the first and second fastening means 225 and 226, the inspection of the electrical connections of these members becomes easier compared to when these members are fixed by crimping or welding. Furthermore, by fastening the electrical connection member 41 and the conductive member 88 and the intermediate member 89 via the first and second fastening means 225 and 226, the reliability of the electrical connections of these members is improved compared to when these members are fixed by a plug-in structure.

[0129] The wiring structure in the electrical device 16 comprises a cylindrical member 40 extending in the axial direction, an electrical connection member 41 electrically connected to the cylindrical member 40, and a fastening target member 89 fastened to the electrical connection member 41. When the electrical device 16 is viewed in the axial direction, the fastening portion F1 between the electrical connection member 41 and the fastening target member 89 is located inside the electrical device 16 and does not overlap with the cylindrical member 40.

[0130] According to this embodiment, space can be easily secured for the tool T used to fasten the electrical connection member 41 and the member to be fastened 89 to pass through. Therefore, the workability of the assembly work of the electrical device 16 is improved. [Explanation of Symbols]

[0131] 16: Propulsion drive system (an example of an electric drive system and electrical equipment) 31: Electric motor 32: Control device 39: Rotor 40: Stator (an example of a cylindrical member) 40A: Inner surface of the stator 41: Electrical connection components 77: Power module (an example of an electronic component) 88: Current sensor (an example of a conductive material) 89: Intermediate busbar (an example of an intermediate component and a component to be fastened) 90: Drive board (an example of a circuit board) 91: Control board (an example of a circuit board) 92: Partition Member 225: First bolt (an example of the first fastening means) 226: Second bolt (an example of a second fastening means) 228: Through hole F1: 1st fastening part F2: Second fastening section

Claims

1. An electric drive device, Electric motor and The system comprises a control device for controlling the aforementioned electric motor, The aforementioned electric motor is stator and, The stator is electrically connected to an electrical connecting member, The electrical connection member is fastened to the control device, When the electric drive device is viewed in the axial direction of the electric motor, the fastening portion between the electrical connection member and the control device is located inside the electric drive device so as not to overlap with the stator.

2. The control device is Conductive material and The device comprises a relay member fastened to the electrical connection member via a first fastening means at the fastening portion, and fastened to the conductive member via a second fastening means at a second fastening portion located at a different position from the fastening portion, The first fastening means is arranged along the axial direction of the electric motor and fastens the electrical connection member and the relay member along the axial direction of the electric motor. The electric drive device according to claim 1, wherein the second fastening means is arranged along the axial direction of the electric motor and fastens the conductive member and the relay member along the axial direction of the electric motor.

3. The electric drive device according to claim 1 or 2, wherein, when viewed in the axial direction of the electric motor, the fastening portion between the electrical connection member and the control device is positioned on the inner side of the inner surface of the stator.

4. The control device is Electronic components and, The circuit board comprises the aforementioned electronic components and electrically connected components, The electric drive device according to claim 3, wherein, when viewed in the axial direction of the electric motor, the circuit board is arranged so as not to overlap with the fastening portion between the electrical connection member and the control device.

5. Multiple electrical connection members are provided. The electric drive device according to claim 4, wherein, when the electric drive device is viewed in the axial direction of the electric motor, the multiple fastening portions between the multiple electrical connection members and the control device are all located on the inner side of the inner circumferential surface of the stator and are concentrated in one semicircular portion of the control device.

6. The control device is Electronic components and, The system includes a current sensor that detects the value of the current output from the aforementioned electronic component, The electric drive device according to claim 3, wherein the fastening portion between the electrical connection member and the control device is arranged adjacent to the current sensor.

7. The system further includes a partitioning member that separates the internal space of the electric motor from the internal space of the control device. The partition member is provided with a through hole along the axial direction of the electric motor. The electric drive device according to claim 1 or 2, wherein, when the electric drive device is viewed in the axial direction of the electric motor, the through hole is provided so as to overlap with the fastening portion between the electrical connection member and the control device.

8. A method for assembling an electric drive device comprising: a stator; a rotor rotatable relative to the stator; an electric motor having an electrical connection member electrically connected to the stator; and a control device for controlling the electric motor, The process of attaching the stator to the control device, A fastening step of fastening the electrical connection member and the control device, The process of bringing the rotor to face the stator is performed sequentially, A method for assembling an electric drive device, wherein, in the fastening step, when viewing the electric drive device in the axial direction of the electric motor, the electrical connection member and the control device are fastened together on the inner side of the inner surface of the stator.

9. The control device is Conductive material and The system comprises the aforementioned electrical connection member and the relay member fastened to the aforementioned conductive member, In the fastening step, the first fastening means is positioned along the axial direction of the electric motor, and the electrical connection member and the relay member are fastened together along the axial direction of the electric motor using the first fastening means. The method for assembling an electric drive device according to claim 8, wherein, before the aforementioned mounting step, a second fastening means is positioned along the axial direction of the electric motor, and the conductive member and the relay member are fastened together with the second fastening means along the axial direction of the electric motor.

10. A wiring structure in an electrical device, A cylindrical member extending in the axial direction, An electrical connecting member electrically connected to the cylindrical member, The system comprises a fastening target member that is fastened to the aforementioned electrical connection member, A wiring structure in an electrical device in which, when the electrical device is viewed in the axial direction, the fastening portion between the electrical connection member and the member to be fastened is located inside the electrical device and does not overlap with the cylindrical member.

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