Propulsion device

Abstract

A propulsion device (15) has a motor device (60) and an outer peripheral duct (120). In the motor device (60), a motor (61) is accommodated in a motor housing (70). In the motor housing (70), a motor fin (79) is provided on a motor outer wall (74). The outer peripheral duct (120) is in a state of covering the motor housing (70) from the outer peripheral side. A duct flow path (123) is formed between a motor outer surface (76) and the outer peripheral duct (120). The motor outer wall (74) is provided with a motor inflow hole (175) and a motor outflow hole (176). Reverse internal wind (W2) flows into a motor space (171) through the motor inflow hole (175), and flows out from the motor space (171) through the motor outflow hole (176) to the duct flow path (123).

Description

propulsion device CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Patent Application No. 2023-184835 filed in Japan on October 27, 2023, and the contents of the original application are incorporated by reference in their entirety.

[0002] The disclosure herein relates to propulsion devices.

[0003] Patent Document 1 describes a propulsion system to be installed in an aircraft or the like. This propulsion system has a motor, an inverter, and a case. The motor and inverter are housed in the case. Heat dissipation fins are provided on the outer surface of the case. The heat dissipation fins dissipate heat from the motor and inverter to the outside of the case.

[0004] International Publication No. 2020 / 115417

[0005] However, in the above-mentioned Patent Document 1, since heat from the motor and inverter is released to the outside through the case, there is a concern that heat may be trapped inside the case, which means that there is a concern that the heat dissipation effect of the case may be insufficient.

[0006] One object of the present disclosure is to provide a propulsion device that can improve heat dissipation efficiency.

[0007] The multiple aspects disclosed in this specification employ different technical means to achieve their respective objectives. Furthermore, the reference symbols in parentheses in the claims and this section are merely examples showing the correspondence between specific means described in the embodiments below as one aspect, and do not limit the technical scope.

[0008] In order to achieve the above object, the first aspect disclosed is a propulsion device for propelling a moving body, comprising: a propulsion drive unit driven by electricity to propel the moving body; and a drive housing that houses the propulsion drive unit, wherein the drive housing has: a housing inner surface that forms a housing space that houses the propulsion drive unit; a housing outer surface that is provided outside the housing inner surface and extends along an outer flow path formed outside the housing inner surface; and a housing outflow hole that connects the outer flow path and the housing space so that gas in the housing space flows out to the outer flow path.

[0009] According to the first aspect, the outer flow passage is provided outside the inner surface of the housing. With this configuration, heat from the propulsion drive unit is released to the outer flow passage through the drive housing. Therefore, the heat dissipation effect of the drive housing can be enhanced by the gas flowing through the outer flow passage. Furthermore, in the drive housing, the outer flow passage and the accommodation space are connected by the housing outlet hole. With this configuration, heat from the propulsion drive unit is easily released, together with the gas, from the accommodation space through the housing outlet hole to the outer flow passage. Therefore, the housing outlet hole and the outer flow passage can prevent heat from building up inside the drive housing. As described above, the housing outlet hole and the outer flow passage can enhance the heat dissipation effect of the propulsion device.

[0010] A second aspect is a propulsion device that is provided in an aircraft having a crew cabin and that propels the aircraft, the propulsion device comprising: a motor that is driven by electricity to propel the aircraft; and a drive housing that houses the motor, wherein the drive housing has: an inner housing surface that forms a housing space that houses the motor; an outer housing surface that is provided outside the inner housing surface and extends along an outer flow path formed outside the inner housing surface; an outer housing wall that extends in the axial direction and covers the motor from the outer periphery; a housing cover wall that covers the motor from the axial direction; a housing outflow hole that is provided in the outer housing wall and connects the outer flow path and the housing space so that gas in the housing space flows out to the outer flow path; and a housing inflow hole that is provided in the housing cover wall and opens the housing space to the outside of the drive housing so that gas flows into the housing space from the outside of the drive housing, and the motor has: a motor rotor that rotates about a rotation axis; and a drive shaft that rotates as the motor is driven, and the drive shaft the motor rotor has: a shaft inlet port that opens the internal space to the outside of the drive shaft so that gas flowing into the housing inlet port flows into the internal space of the drive shaft; and a shaft outlet port that connects the internal space and the housing space so that gas in the internal space flows out into the housing space; the motor rotor has: rotor blades that blow air so that gas flows out of the housing outlet port into an outer flow path as the motor rotor rotates; and a foreign matter control section that allows gas to flow into the housing inlet port while preventing foreign matter from entering the housing space from the housing inlet port; an outflow control section that is provided for the housing outlet port and is switchable between a restricted state that restricts the outflow of gas from the housing outlet port and an allowed state that allows the outflow of gas from the housing outlet port; the outflow control section has an elastic control section that elastically deforms in response to the flow of gas in the outer flow path to switch from the restricted state to the allowed state, and that switches from the allowed state to the restricted state due to a restoring force that resists the flow of gas in the outer flow path; and a blower fan that blows air so that gas flows out of the housing space through the housing outlet port into the outer flow path.an outer duct covering the housing outer surface and the housing outlet hole from the outside so as to form an outer flow path between the housing outer surface and the outer duct.

[0011] According to the second aspect, similarly to the first aspect, the heat dissipation effect of the propulsion device can be improved by the housing outlet holes and the outer flow passage.

[0012] 4 is a diagram showing the configuration of an eVTOL in a first embodiment. A block diagram showing the electrical configuration of an EPU. A schematic vertical cross-sectional view of a propulsion device. A cross-sectional view of the propulsion device taken along line IV-IV in FIG. 3, and a schematic horizontal cross-sectional view of the propulsion device. A vertical cross-sectional view of the periphery of the motor space in the propulsion device. A diagram for explaining the behavior of water droplets in a first situation. A diagram for explaining the behavior of water droplets in a second situation. A diagram for explaining the behavior of water droplets in a third situation. A diagram for explaining the behavior of water droplets in a fourth situation. A diagram for explaining the behavior of water droplets in a fifth situation. A schematic vertical cross-sectional view of a propulsion device in a second embodiment. A diagram for explaining the behavior of water droplets in a sixth situation. A diagram for explaining the behavior of water droplets in a seventh situation. A schematic vertical cross-sectional view of a propulsion device in a third embodiment. A schematic vertical cross-sectional view of a propulsion device in a fourth embodiment. A schematic vertical cross-sectional view of a propulsion device in a fifth embodiment. A block diagram showing the electrical configuration of an EPU. A flowchart showing the procedure of EPU control processing. A flowchart showing the procedure of EPU control processing in a sixth embodiment. A flowchart showing the procedure of EPU control processing in a seventh embodiment. 13. A flowchart showing the procedure of EPU control processing in the eighth embodiment. A diagram for explaining the opening and closing operation of an outflow control valve. A schematic vertical cross-sectional view of a propulsion device in the ninth embodiment. A vertical cross-sectional view of the periphery of the motor space in the propulsion device. A schematic vertical cross-sectional view of a propulsion device in the tenth embodiment. A schematic vertical cross-sectional view of a propulsion device in the eleventh embodiment. A schematic vertical cross-sectional view of a propulsion device in the twelfth embodiment. A schematic vertical cross-sectional view of a propulsion device in the thirteenth embodiment. A schematic vertical cross-sectional view of a propulsion device in the fourteenth embodiment. A schematic vertical cross-sectional view of a propulsion device in the fifteenth embodiment. A schematic vertical cross-sectional view of a propulsion device in the sixteenth embodiment. A schematic vertical cross-sectional view of a propulsion device in the seventeenth embodiment.

[0013] Hereinafter, several embodiments for carrying out the present disclosure will be described with reference to the drawings. In each embodiment, parts corresponding to matters described in the preceding embodiment will be assigned the same reference numerals, and duplicate descriptions may be omitted. In each embodiment, when only a part of the configuration is described, other previously described embodiments may be applied to the other parts of the configuration. In addition to combinations of parts that are specifically specified as being combinable in each embodiment, it is also possible to partially combine embodiments even if not specified, as long as there is no particular problem with the combination.

[0014] First Embodiment The propulsion system 30 shown in FIG. 1 is mounted on an eVTOL 10. The eVTOL 10 is an electric vertical take-off and landing aircraft. An electric vertical take-off and landing aircraft is an electric vertical take-off and landing aircraft capable of vertical take-off and landing. eVTOL is an abbreviation for electric Vertical Take-Off and Landing aircraft. The eVTOL 10 is an electric air vehicle that flies in the atmosphere and is sometimes referred to as an electric air vehicle. The eVTOL 10 is also an electric aircraft and is sometimes referred to as an electric aircraft. The eVTOL 10 is a manned air vehicle that carries a crew member. The crew member of the eVTOL 10 includes a pilot who operates or drives the aircraft. The propulsion system 30 is a system that drives the eVTOL 10 to fly. The propulsion system 30 is sometimes referred to as a flight system.

[0015] The eVTOL 10 has an airframe 11 and a propeller 20. The airframe 11 has an airframe main body 12 and wings 13. The airframe main body 12 is the fuselage of the airframe 11 and has a shape that extends, for example, in the front-to-rear direction. The wings 13 extend from the airframe main body 12, and multiple wings 13 are provided on the airframe main body 12. The wings 13 are fixed wings. The multiple wings 13 include main wings, a tail, and the like.

[0016] The eVTOL 10 has a cabin. The cabin is provided inside the eVTOL 10. For example, the cabin is the internal space of the aircraft body 12 and is formed by the aircraft body 12. The cabin can be a crew cabin 14 or a cargo bay. The crew cabin 14 can be a passenger cabin or a pilot cabin. The crew cabin 14 is provided with seats for crew members to sit in. The crew cabin 14 does not have to be occupied by crew members and may house cargo.

[0017] A plurality of propellers 20 are provided on the airframe 11. The eVTOL 10 is a multicopter having at least three propellers 20. For example, at least four propellers 20 are provided on the airframe 11. A propeller 20 is provided on each of the airframe body 12 and the wings 13. The propellers 20 rotate around a propeller axis Cp. The propeller axis Cp is the axis of rotation of the propellers 20. The propeller axis Cp is, for example, the center line of the propellers 20. The propellers 20 can generate thrust and lift for the eVTOL 10. The propellers 20 are sometimes referred to as rotors or rotating blades.

[0018] The propeller 20 has propeller blades 21 and a propeller boss 22. A plurality of the propeller blades 21 are arranged in the circumferential direction of the propeller axis Cp. The propeller boss 22 connects the plurality of propeller blades 21. In the propeller 20, a propeller shaft 23 extends from the propeller boss 22 along the propeller axis Cp.

[0019] Flight modes of the eVTOL 10 include vertical takeoff, vertical landing, cruise, and hovering. Flight modes are sometimes referred to as flight behaviors. In vertical takeoff, the eVTOL 10 can take off without running. In vertical takeoff, the eVTOL 10 may ascend vertically or may ascend diagonally upward. In vertical landing, the eVTOL 10 can land without running. In vertical landing, the eVTOL 10 may descend vertically or may descend diagonally downward.

[0020] Cruising is sometimes referred to as level flight. In cruising, the eVTOL 10 may fly horizontally without moving vertically, or may fly horizontally while moving vertically. Hovering is sometimes referred to as stationary flight. In hovering, the eVTOL 10 may fly as if stationary at a predetermined position in the air, or the eVTOL 10 may deviate vertically or horizontally from the predetermined position.

[0021] The flight modes of the eVTOL 10 also include lift. In lift, the eVTOL 10 moves up and down. As a lift, the eVTOL 10 may ascend diagonally upward or descend diagonally downward. The eVTOL 10 takes off vertically by lifting upward. The eVTOL 10 lands vertically by lifting downward.

[0022] The eVTOL 10 is a tilt rotor aircraft. The eVTOL 10 has an adjustable tilt angle for the propeller 20. The eVTOL 10 can have one propeller 20 function as both a lift propeller and a cruise propeller. For example, when the eVTOL 10 lifts, the tilt angle is adjusted so that the propeller 20 functions as a lift rotor. When the eVTOL 10 cruises, the tilt angle is adjusted so that the propeller 20 functions as a cruise rotor. Note that the eVTOL 10 does not have to be a tilt rotor aircraft. For example, the eVTOL 10 may have separate propellers 20 for lift and cruise.

[0023] The eVTOL 10 has a battery 31, a distributor 32, a communication unit 34, a flight control device 40, and an EPU 50. The battery 31, distributor 32, communication unit 34, flight control device 40, and EPU 50 are included in a propulsion system 30. Note that the propulsion system 30 only needs to include at least the flight control device 40 and the EPU 50. The flight control device 40 is sometimes referred to as a flight controller.

[0024] The battery 31 is electrically connected to the EPU 50. The battery 31 is a power supply unit that supplies power to the EPU 50 and corresponds to a power supply unit. The battery 31 is a DC voltage source that applies a DC voltage to the EPU 50. The battery 31 has a rechargeable secondary battery. Examples of such secondary batteries include a lithium ion battery and a nickel-metal hydride battery. The battery 31 is capable of storing power and corresponds to a power storage device. Note that a fuel cell, a generator, or the like may be used as the power supply unit in addition to or instead of the battery 31.

[0025] The distributor 32 is electrically connected to the battery 31 and the plurality of EPUs 50. The distributor 32 distributes power from the battery 31 to the plurality of EPUs 50. The battery 31 is electrically connected to the plurality of EPUs 50 via the distributor 32. The battery 31 supplies power to the EPUs 50 via the distributor 32.

[0026] The communication unit 34 is a communication device capable of wireless communication with an external device. The external device is a device located away from the eVTOL 10. Examples of external devices include communication devices installed in external facilities on the ground and communication devices installed in other flying vehicles. Examples of external facilities include a control center and a management center. The communication unit 34 is capable of communication with the flight control device 40. The communication unit 34 is connected to the flight control device 40 so that it can communicate via wired communication. Note that the communication unit 34 may also be capable of wireless communication with the flight control device 40.

[0027] 1 to 3, the EPU 50 is a device that drives the propeller 20 to rotate, and corresponds to a drive device. EPU is an abbreviation for Electric Propulsion Unit. The EPU 50 is sometimes referred to as an electric drive device or an electric drive system. An EPU 50 is provided for each of the multiple propellers 20. The EPUs 50 are arranged on the propellers 20 along the propeller axis Cp. All of the multiple EPUs 50 are fixed to the airframe 11. The EPUs 50 support the propellers 20 so that they can rotate. The EPUs 50 are connected to the propellers 20. The propellers 20 are fixed to the airframe 11 via the EPUs 50.

[0028] The eVTOL 10 has a propulsion device 15. The propulsion device 15 is formed to include a propeller 20 and an EPU 50. The propulsion device 15 is a device for propelling the eVTOL 10. The propulsion device 15 causes the eVTOL 10 to fly by rotating the propeller 20. The eVTOL 10 is a moving body that moves using the propulsion device 15. A plurality of propulsion devices 15 are provided in the eVTOL 10. Each propulsion device 15 includes one propeller 20 and one EPU 50 for driving the propeller 20. Note that only the EPU 50 of the propeller 20 and the EPU 50 may be referred to as the propulsion device 15.

[0029] The EPU 50 has a motor device 60 and an inverter device 80. The motor device 60 and the inverter device 80 are formed as a whole in the shape of a short cylinder, and extend in the axial direction AD. The motor device 60 and the inverter device 80 are aligned in the axial direction AD. The motor device 60 and the inverter device 80 are stacked in the axial direction AD. The motor device 60 and the inverter device 80 are provided coaxially. The center line of the inverter device 80 coincides with the motor axis line Cm. The motor device 60 is provided between the inverter device 80 and the propeller 20 in the axial direction AD.

[0030] The motor device 60 has a motor 61 and a motor housing 70. The motor housing 70 is a housing and houses the motor 61. The motor housing 70 has a motor space 171 (see FIG. 3). The motor space 171 is the internal space of the motor housing 70. The motor 61 is housed in the motor space 171. The motor housing 70 corresponds to a drive housing. The motor space 171 corresponds to a housing space.

[0031] The motor 61 is driven to propel the eVTOL 10. The motor 61 is driven by power from the battery 31. The motor 61 corresponds to the propulsion drive unit. The motor device 60 is the flight drive source for the eVTOL 10 and functions as an electric motor. The motor 61 is a multi-phase AC motor. For example, the motor 61 is a brushless motor. The motor 61 is sometimes referred to as a rotating electric machine. The motor 61 is a motor generator. The motor 61 functions as a generator during regeneration.

[0032] The motor 61 has a motor stator 62, a motor rotor 64, and a motor shaft 65. The motor 61 is configured to include mechanical components such as the motor stator 62, the motor rotor 64, and the motor shaft 65. The motor stator 62 is a stator and is fixed to a motor housing 70. The motor stator 62 has a stator coil 62a (see FIG. 5). The stator coil 62a is a multi-phase coil. The stator coil 62a is a winding and forms an armature. In FIG. 2, the motor device 60 is illustrated as eMOT, the motor stator 62 as Sta, and the motor rotor 64 as Rot.

[0033] The motor rotor 64 is a rotor and rotates relative to the motor stator 62. The motor rotor 64 has rotor magnets 149 (see FIG. 5). The rotor magnets 149 are formed of permanent magnets or the like. The rotor magnets 149 form a magnetic field. A plurality of the rotor magnets 149 are arranged in the circumferential direction CD.

[0034] The motor shaft 65 supports the motor rotor 64. The motor shaft 65 rotates together with the motor rotor 64. The motor shaft 65 is rotatably supported by bearings or the like. The motor shaft 65 is made of a metal material or the like and has thermal conductivity. The motor shaft 65 extends in the axial direction AD. The motor shaft 65 is connected to the propeller 20. In the propulsion unit 15, the propeller 20 rotates together with the motor shaft 65. The motor shaft 65 rotates as the motor 61 is driven. The motor shaft 65 corresponds to a drive shaft.

[0035] The motor 61 is an axial gap motor. In the motor 61, a motor stator 62 and a motor rotor 64 are aligned in the axial direction AD. The motor 61 is also a double-rotor motor. In the motor 61, the two motor rotors 64 are aligned in the axial direction AD via the motor stator 62.

[0036] The axial direction AD is the direction in which the motor axis Cm extends. The motor axis Cm is the rotation axis of the motor rotor 64. The motor rotor 64 rotates around the motor axis Cm. The motor axis Cm is, for example, the center line of the motor rotor 64. The motor axis Cm is also the center line of the motor 61, the motor stator 62, and the motor shaft 65. The motor axis Cm corresponds to the rotation axis. With respect to the motor axis Cm, the axial direction AD, the radial direction RD, and the circumferential direction CD are perpendicular to one another. The outside of the radial direction RD is sometimes referred to as the radial outside or outer circumferential side. The inside of the radial direction RD is sometimes referred to as the radial inside or inner circumferential side.

[0037] The inverter device 80 drives the motor device 60. The inverter device 80 is sometimes referred to as a motor drive device or a power conversion device. As shown in FIG. 3 , the inverter device 80 has an inverter unit 86 and an inverter housing 90. The inverter housing 90 is a case and houses the inverter unit 86. The inverter unit 86 is housed in the internal space of the inverter housing 90. The inverter unit 86 as a whole extends annularly in the circumferential direction CD.

[0038] The inverter unit 86 is driven to propel the eVTOL 10. The inverter unit 86 is driven by power from the battery 31. The inverter unit 86 supplies power to the motor 61 to drive the motor 61. The inverter unit 86 converts the power supplied to the motor 61. The inverter unit 86 is sometimes referred to as a motor drive unit or a power conversion unit.

[0039] As shown in Fig. 2, the inverter device 80 has an inverter circuit 81 and an inverter control unit 82. The inverter circuit 81 is a circuit for converting power. The inverter circuit 81 performs power conversion for each of the multiple phases. The inverter circuit 81 converts DC power from the battery 31 into AC power and supplies the AC power to the motor 61. The inverter circuit 81 is, for example, a DC-AC conversion circuit. For example, the inverter circuit 81 has upper and lower arm circuits for the multiple phases.

[0040] The inverter control unit 82 performs motor control to control the motor 61. The inverter control unit 82 is communicably connected to the inverter circuit 81. The inverter control unit 82 performs motor control by controlling the inverter circuit 81. The inverter control unit 82 outputs a command signal to the inverter circuit 81. The inverter control unit 82 may be referred to as a control circuit or a motor control unit.

[0041] The inverter control unit 82 is a control device such as an ECU. ECU is an abbreviation for Electronic Control Unit. The inverter control unit 82 has a processor 83, a memory 84, and a program 85. The inverter control unit 82 is mainly configured as a computer. This computer has the processor 83, the memory 84, an input / output interface, a bus connecting these, etc. The memory 84 stores the program 85. The program 85 is a program for performing flight control. In FIG. 2 , the inverter circuit 81 is illustrated as INV, the inverter control unit 82 as MCU, the inverter control unit 82 as ICD, the processor 83 as PRO, the memory 84 as MEM, and the program 85 as PG.

[0042] The processor 83 is hardware for arithmetic processing coupled to the memory 84. The processor 83 executes various processes such as flight control processing by accessing the memory 84. The memory 84 is a storage medium that stores control programs and the like. For example, the memory 84 is a non-transitory tangible storage medium that non-temporarily stores computer-readable programs and data. The non-transitory tangible storage medium is a non-transitory tangible storage medium, and is realized by a semiconductor memory, a magnetic disk, or the like. The program 85 includes computer-readable instructions that cause the processor 83 to perform various functions. The processor 83 is a processing unit that executes predetermined processes by executing instructions included in the program 85.

[0043] The EPU 50 has one motor device 60 and multiple inverter devices 80. In the EPU 50, the multiple inverter devices 80 control one motor device 60. For example, the stator coil 62a has multiple individual coils. The individual coils are multiple-phase coils. One inverter circuit 81 drives the motor 61 by supplying power to at least one individual coil. Another inverter circuit 81 drives the motor 61 by supplying power to another individual coil. In this embodiment, the stator coil 62a has two three-phase coils, making it a six-phase coil. The motor 61 is driven as a six-phase motor by supplying power to the two three-phase coils from the two inverter devices 80.

[0044] 2 and 3 , the inverter unit 86 forms an inverter circuit 81, an inverter control unit 82, etc. The inverter unit 86 has a circuit board, switch components, etc. In the inverter unit 86, the inverter circuit 81 and the inverter control unit 82 are formed by mounting the switch components on the circuit board, etc. The inverter unit 86 may also have capacitor components, filter components, etc.

[0045] As shown in Figure 2, the eVTOL 10 has a flight control device 40. The flight control device 40 performs flight control for flying the eVTOL 10. The flight control device 40 controls various devices such as the EPU 50 mounted on the eVTOL 10. The flight control includes EPU control for driving the EPU 50. The EPU control includes motor control for driving the motor 61.

[0046] The flight control device 40 is a control device such as an ECU. The flight control device 40 has a processor 41, a memory 42, and a program 43. The flight control device 40 is mainly composed of a computer. This computer has the processor 41, memory 42, an input / output interface, a bus connecting these, etc. The memory 42 stores the program 43. The program 43 is a program for performing flight control. In Figure 2, the flight control device 40 is shown as an ECU, the processor 41 as PRO, the memory 42 as MEM, and the program 43 as PG.

[0047] The processor 41 is hardware for arithmetic processing coupled to the memory 42. The processor 41 executes various processes such as flight control processing by accessing the memory 42. The memory 42 is a storage medium that stores control programs and the like. For example, the memory 42 is a non-transient tangible storage medium that non-temporarily stores computer-readable programs and data. The program 43 includes computer-readable instructions that cause the processor 41 to execute various functions. The processor 41 is a processing unit that executes predetermined processes by executing instructions included in the program 43.

[0048] The flight control device 40 is communicatively connected to the inverter control unit 82. The flight control device 40 performs flight control in accordance with the detection results of various sensors. This flight control includes propulsion control for driving the propulsion device 15. The propulsion control includes EPU control for driving the EPU 50 and motor control for driving the motor 61. The flight control device 40 outputs command signals and the like to the inverter control unit 82. The flight control device 40 corresponds to a propulsion control device.

[0049] The inverter control unit 82 performs motor control to drive the motor device 60. As motor control, the inverter control unit 82 controls the power supplied from the inverter circuit 81 to the stator coil 62a. For example, in motor control, the supply of current to the stator coil 62a is controlled. The inverter control unit 82 performs motor control in response to command signals from the flight control device 40, etc.

[0050] As shown in Figure 3, the motor housing 70 is a cylindrical housing overall. The motor housing 70 has a motor outer wall 74 and motor fins 79. The motor outer wall 74 and the motor fins 79 are made of a metal material or the like and have thermal conductivity. The motor outer wall 74 is the outer wall of the motor housing 70. The motor outer wall 74 forms the outer and inner surfaces of the motor housing 70. The motor outer wall 74 forms a motor space 171. The motor outer wall 74 extends in a wall-like shape along the outer and inner surfaces of the motor housing 70.

[0051] The motor outer wall 74 has a motor outer surface 76 and a motor inner surface 77. The motor outer surface 76 is the outer surface of the motor outer wall 74. The motor outer surface 76 forms the outer surface of the motor housing 70. The motor inner surface 77 is the inner surface of the motor outer wall 74. The motor inner surface 77 forms the inner surface of the motor housing 70. The motor inner surface 77 forms a motor space 171. The motor inner surface 77 corresponds to the inner surface of the housing. The motor outer surface 76 is provided outside the motor inner surface 77. The motor outer surface 76 corresponds to the outer surface of the housing.

[0052] As shown in FIG. 5 , the motor outer surface 76 has a motor outer peripheral outer surface 76a and a motor-facing outer surface 76b. The motor outer peripheral outer surface 76a is a portion of the motor outer surface 76 that extends in a direction perpendicular to the radial direction RD. The motor outer peripheral outer surface 76a extends annularly in the circumferential direction CD. The motor-facing outer surface 76b is a portion of the motor outer surface 76 that extends in a direction perpendicular to the axial direction AD. A pair of motor-facing outer surfaces 76b are arranged in the axial direction AD with the motor outer peripheral outer surface 76a interposed therebetween. The motor outer peripheral outer surface 76a extends in the axial direction AD so as to bridge the pair of motor-facing outer surfaces 76b.

[0053] The motor inner surface 77 has a motor outer peripheral inner surface 77a and a motor-facing inner surface 77b. The motor outer peripheral inner surface 77a is a portion of the motor inner surface 77 that extends in a direction perpendicular to the radial direction RD. The motor outer peripheral inner surface 77a extends annularly in the circumferential direction CD. The motor outer peripheral inner surface 77a is provided on the inner peripheral side of the motor outer peripheral outer surface 76a in the radial direction RD. The motor-facing inner surface 77b is a portion of the motor inner surface 77 that extends in a direction perpendicular to the axial direction AD. A pair of motor-facing inner surfaces 77b are arranged in the axial direction AD with the motor outer peripheral inner surface 77a interposed between them. The motor outer peripheral inner surface 77a extends in the axial direction AD so as to bridge between the pair of motor-facing inner surfaces 77b. The motor-facing inner surface 77b is provided inside the motor-facing outer surface 76b in the axial direction AD.

[0054] As shown in Figures 3 and 5, the motor outer wall 74 has a motor outer peripheral wall 71, a first motor facing wall 73a, and a second motor facing wall 73b. The motor outer peripheral wall 71 is the outer peripheral wall of the motor housing 70. The motor outer peripheral wall 71 is a portion of the motor outer wall 74 that extends in a direction perpendicular to the radial direction RD. The motor outer peripheral wall 71 extends annularly in the circumferential direction CD. The motor outer peripheral wall 71 forms a motor outer peripheral surface 76a and a motor outer peripheral inner surface 77a. The motor outer peripheral wall 71 covers at least a portion of the motor 61 from the outer periphery. For example, the motor outer peripheral wall 71 is formed of a cylindrical member. The motor outer peripheral wall 71 corresponds to the housing outer peripheral wall.

[0055] The motor-facing walls 73a, 73b are opposing walls of the motor housing 70. The motor-facing walls 73a, 73b are portions of the motor outer wall 74 that extend in a direction perpendicular to the axial direction AD. The first motor-facing wall 73a and the second motor-facing wall 73b are aligned in the axial direction AD. The first motor-facing wall 73a and the second motor-facing wall 73b face each other across the motor outer peripheral wall 71. The second motor-facing wall 73b is provided on the opposite side of the first motor-facing wall 73a from the propeller 20. The second motor-facing wall 73b corresponds to a housing covering wall.

[0056] The motor outer peripheral wall 71 is suspended between the first motor facing wall 73a and the second motor facing wall 73b. The motor facing walls 73a, 73b form a motor facing outer surface 76b and a motor facing inner surface 77b. The motor facing walls 73a, 73b cover at least a portion of the motor 61 in the axial direction AD. For example, the motor facing walls 73a, 73b are formed of plate-like members such as end plates. The plate-like members forming the motor facing walls 73a, 73b are fixed to the cylindrical member forming the motor outer peripheral wall 71 with bolts or the like.

[0057] The motor fins 79 are provided on the motor outer surface 76. For example, the motor fins 79 are provided on the motor outer peripheral outer surface 76a. The motor fins 79 extend from the motor outer peripheral outer surface 76a toward the outer periphery. The motor fins 79 are provided on the motor outer wall 74. For example, the motor fins 79 are provided on the motor outer peripheral wall 71. The motor fins 79 can release heat from the motor 61 to the outside of the motor housing 70. The motor fins 79 are heat dissipation fins. The motor fins 79 extend in a direction perpendicular to the circumferential direction CD.

[0058] 4, the motor fins 79 are arranged in the circumferential direction CD. The motor fins 79 are arranged in the circumferential direction CD along the outer peripheral edge of the motor 61. For example, the motor fins 79 are arranged in the circumferential direction CD along the outer peripheral edge of the motor rotor 64 or the outer peripheral edge of the motor stator 62.

[0059] As shown in Fig. 3, the inverter housing 90 is an overall annular housing. The inverter housing 90 has an inverter housing hole 95. The inverter housing hole 95 penetrates the inverter housing 90 in the axial direction AD. The inverter housing hole 95 extends in the axial direction AD along the motor axis Cm. The inverter housing hole 95 is provided in the center of the inverter housing 90. The center line of the inverter housing hole 95 coincides with the motor axis Cm.

[0060] The inverter housing 90 has an inverter outer wall 94 and inverter fins 99. The inverter outer wall 94 and the inverter fins 99 are formed from a metal material or the like and have thermal conductivity. The inverter outer wall 94 is the outer wall of the inverter housing 90. The inverter outer wall 94 forms the outer surface and inner surface of the inverter housing 90. The inverter outer wall 94 forms the internal space of the inverter housing 90. The inverter outer wall 94 extends in a wall shape along the outer surface of the inverter housing 90.

[0061] The inverter outer wall 94 has an inverter outer surface 96 and an inverter inner surface 97. The inverter outer surface 96 is the outer surface of the inverter outer wall 94. The inverter outer surface 96 forms the outer surface of the inverter housing 90. The inverter inner surface 97 is the inner surface of the inverter outer wall 94. The inverter inner surface 97 forms the inner surface of the inverter housing 90. The inverter inner surface 97 forms the internal space of the inverter housing 90.

[0062] The inverter outer surface 96 has an inverter outer peripheral outer surface 96a. The inverter outer peripheral outer surface 96a is a portion of the inverter outer surface 96 that extends in a direction perpendicular to the radial direction RD. The inverter outer peripheral outer surface 96a extends annularly in the circumferential direction CD. The inverter outer surface 96 has an inverter-facing outer surface and an inverter inner peripheral outer surface. The inverter-facing outer surface is a portion of the inverter outer surface 96 that extends in a direction perpendicular to the axial direction AD. The inverter inner peripheral outer surface is a portion of the inverter outer surface 96 that forms the inverter housing hole 95.

[0063] The inverter inner surface 97 has an inverter outer peripheral inner surface 97a. The inverter outer peripheral inner surface 97a is a portion of the inverter inner surface 97 that extends in a direction perpendicular to the radial direction RD. The inverter outer peripheral inner surface 97a extends annularly in the circumferential direction CD. The inverter outer peripheral inner surface 97a is provided on the inner peripheral side of the inverter outer peripheral outer surface 96a in the radial direction RD. The inverter inner surface 97 has an inverter-facing inner surface. The inverter-facing inner surface is a portion of the inverter inner surface 97 that extends in a direction perpendicular to the axial direction AD.

[0064] The inverter outer wall 94 has an inverter outer peripheral wall 91, an inverter inner peripheral wall 92, and an inverter facing wall 93. The inverter outer peripheral wall 91 and the inverter inner peripheral wall 92 are portions of the inverter outer wall 94 that extend in a direction perpendicular to the radial direction RD. The inverter outer peripheral wall 91 and the inverter inner peripheral wall 92 extend annularly in the circumferential direction CD. The inverter outer peripheral wall 91 is the outer peripheral wall of the inverter housing 90. The inverter outer peripheral wall 91 forms an inverter outer peripheral surface 96a. The inverter outer peripheral wall 91 covers at least a portion of the inverter section 86 from the outer periphery side. The inverter inner peripheral wall 92 forms an inverter housing hole 95. The inverter inner peripheral wall 92 is located at a position spaced inward from the inverter outer peripheral wall 91.

[0065] The inverter facing walls 93 are facing walls of the inverter housing 90. The inverter facing walls 93 are portions of the inverter outer wall 94 that extend in a direction perpendicular to the axial direction AD. A pair of inverter facing walls 93 are arranged in the axial direction AD. The pair of inverter facing walls 93 face each other with the inverter outer peripheral wall 91 interposed therebetween. The inverter outer peripheral wall 91 is suspended between the pair of inverter facing walls 93. The inverter facing walls 93 form an inverter-facing outer surface and an inverter-facing inner surface. The inverter facing wall 93 covers at least a portion of the inverter section 86 from the axial direction AD.

[0066] The inverter fins 99 are provided on the inverter outer surface 96. For example, the inverter fins 99 are provided on the inverter outer peripheral outer surface 96a. The inverter fins 99 extend from the inverter outer peripheral outer surface 96a toward the outer periphery. The inverter fins 99 are provided on the inverter outer wall 94. For example, the inverter fins 99 are provided on the inverter outer peripheral wall 91. The inverter fins 99 can dissipate heat from the inverter section 86 to the outside of the inverter housing 90. The inverter fins 99 are heat dissipation fins. The inverter fins 99 extend in a direction perpendicular to the circumferential direction CD. A plurality of the inverter fins 99 are arranged in the circumferential direction CD. The plurality of inverter fins 99 are arranged in the circumferential direction CD along the outer periphery edge of the inverter section 86.

[0067] The EPU 50 has a gear device 100. The gear device 100 mechanically connects the motor device 60 and the propeller 20. The gear device 100 transmits the drive of the motor device 60 to the propeller 20. The gear device 100 is provided between the motor device 60 and the propeller 20 in the axial direction AD. The gear device 100 is sometimes referred to as a gear box. The gear device 100 is formed in a short cylindrical shape as a whole and extends in the axial direction AD. The gear device 100 is aligned with the motor device 60 and the inverter device 80 in the axial direction AD. The gear device 100 is provided between the motor device 60, the inverter device 80, and the propeller 20 in the axial direction AD. The gear device 100 is provided coaxially with the motor device 60 and the inverter device 80. The center line of the gear device 100 coincides with the motor axis line Cm.

[0068] The gear device 100 includes a gear 101, a gear shaft 102, and a gear housing 105. The gear shaft 102 extends in the axial direction AD and connects the motor shaft 65 and the propeller shaft 23. The gear 101 includes a reducer and is provided on the gear shaft 102.

[0069] The gear housing 105 accommodates the gear 101. The gear housing 105 has a gear outer peripheral wall 106 and a gear opposing wall 107. The gear outer peripheral wall 106 extends annularly in the circumferential direction CD. The gear outer peripheral wall 106 forms the outer peripheral surface of the gear housing 105. The gear outer peripheral wall 106 covers the gear 101 from the radially outside. A pair of gear opposing walls 107 are arranged in the axial direction AD. The pair of gear opposing walls 107 are arranged in the axial direction AD with the gear 101 interposed between them. The gear outer peripheral wall 106 and the gear opposing wall 107 are formed from a metal material or the like and have thermal conductivity.

[0070] In the propulsion device 15, the propeller axis Cp and the motor axis Cm extend parallel to each other. For example, the propeller axis Cp and the motor axis Cm are aligned. In the propulsion device 15, a propeller wind Wp is generated as the propeller 20 rotates. The propeller wind Wp is a flow of gas, such as air. The propeller wind Wp flows in the axial direction AD along the propeller axis Cp. For example, the propeller wind Wp flows from the propeller 20 toward the EPU 50 in the axial direction AD. In the propeller 20, the rotation direction of the propeller 20 and the orientation of the propeller blades 21 are set so that the propeller wind Wp flows from the propeller 20 toward the EPU 50. The propeller blades 21 are inclined in the circumferential direction CD with respect to the propeller axis Cp. With respect to the propeller wind Wp, the EPU 50 is on the downwind side of the propeller 20.

[0071] In the eVTOL 10, moving wind Wm (see FIG. 7, etc.) is generated as the eVTOL 10 moves. The moving wind Wm is a flow of gas such as air. The moving wind Wm flows in the direction of travel of the eVTOL 10. When the axial direction AD coincides with the direction of travel of the eVTOL 10, the moving wind Wm flows in the axial direction AD in the same way as the propeller wind Wp.

[0072] The EPU 50 has an outer circumferential duct 120. The outer circumferential duct 120 extends annularly in the circumferential direction CD. The outer circumferential duct 120 extends in the axial direction AD. The outer circumferential duct 120 is provided so as to cover the motor housing 70 and the inverter housing 90 from the outer periphery. The outer circumferential duct 120 is aligned with the propeller 20 in the axial direction AD. The outer circumferential duct 120 extends from the motor housing 70 and the inverter housing 90 to both sides in the axial direction AD. The outer circumferential duct 120 is made of a resin material. Note that the outer circumferential duct 120 may also be made of a metal material, a rubber material, or the like.

[0073] The outer circumferential duct 120 is open to both sides in the axial direction AD. The outer circumferential duct 120 has a first duct port 121 and a second duct port 122. The first duct port 121 and the second duct port 122 are aligned in the axial direction AD. The first duct port 121 opens the internal space of the outer circumferential duct 120 toward the propeller 20. The first duct port 121 is provided between the motor housing 70 and the propeller 20 in the axial direction AD. The second duct port 122 opens the internal space of the outer circumferential duct 120 toward the opposite side from the propeller 20 in the axial direction AD. The second duct port 122 is provided on the opposite side from the propeller 20 across the motor housing 70 and the inverter housing 90.

[0074] The outer periphery duct 120 forms a duct flow path 123 between the motor housing 70 and the inverter housing 90. The duct flow path 123 is included in the EPU 50. The duct flow path 123 extends annularly in the circumferential direction CD between the housings 70, 90 and the outer periphery duct 120. The duct flow path 123 also extends in the axial direction AD between the housings 70, 90 and the outer periphery duct 120. The duct flow path 123 extends annularly in the circumferential direction CD along the motor outer peripheral outer surface 76a and the inverter outer peripheral outer surface 96a. The duct flow path 123 also extends in the axial direction AD along the outer peripheral outer surfaces 76a, 96a. The duct flow path 123 is provided outside the motor inner surface 77 and the inverter inner surface 97. For example, the duct flow path 123 is provided on the outer peripheral side of the motor outer peripheral inner surface 77a and the inverter outer peripheral inner surface 97a. The duct flow path 123 corresponds to an outer flow path.

[0075] The duct flow path 123 is open to both sides in the axial direction AD. The duct flow path 123 is opened toward the propeller 20 by a first duct port 121. The duct flow path 123 is opened toward the opposite side from the propeller 20 by a second duct port 122. The duct flow path 123 is a space for introducing gas to the outside of the motor housing 70. The duct flow path 123, the first duct port 121, and the second duct port 122 are sometimes referred to as outside introduction portions.

[0076] The duct flow path 123 includes a motor outer circumferential flow path 78 and an inverter outer circumferential flow path 98. The motor outer circumferential flow path 78 is a flow path that extends in the axial direction AD and the circumferential direction CD along the motor outer circumferential outer surface 76a. The motor outer circumferential flow path 78 is a space defined by the motor outer circumferential outer surface 76a and the motor fins 79. The motor outer circumferential flow path 78 extends in the axial direction AD so as to span the pair of motor-facing outer surfaces 76b. The motor outer circumferential flow path 78 includes the space between two adjacent motor fins 79 in the circumferential direction CD. The thickness dimension of the motor outer circumferential flow path 78 in the radial direction RD is the same as the protrusion dimension of the motor fins 79 from the motor outer circumferential outer surface 76a.

[0077] The motor outer circumferential flow passage 78 is provided outside the motor inner surface 77. For example, the motor outer circumferential flow passage 78 is provided on the outer peripheral side of the motor outer circumferential inner surface 77a. The motor outer circumferential flow passage 78 corresponds to an outer flow passage. Similar to the duct flow passage 123, the motor outer circumferential flow passage 78 is a space for introducing gas to the outside of the motor housing 70. The motor outer circumferential flow passage 78 is sometimes referred to as an outer introduction section.

[0078] The inverter outer circumferential flow passage 98 is a flow passage that extends in the axial direction AD and the circumferential direction CD along the inverter outer circumferential outer surface 96a. The inverter outer circumferential flow passage 98 is a space defined by the inverter outer circumferential outer surface 96a and the inverter fins 99. The inverter outer circumferential flow passage 98 extends in the axial direction AD so as to span the pair of inverter opposing walls 93. The inverter outer circumferential flow passage 98 includes a space between two inverter fins 99 adjacent to each other in the circumferential direction CD. The thickness dimension of the inverter outer circumferential flow passage 98 in the radial direction RD is the same as the protrusion dimension of the inverter fins 99 from the inverter outer circumferential outer surface 96a.

[0079] The outer duct 120 contacts the tip ends of the motor fins 79 and the inverter fins 99. Therefore, the thickness dimension of the duct flow path 123 in the radial direction RD is the same as the thickness dimension of the outer circumferential flow paths 78, 98. In other words, the motor outer circumferential flow path 78 and the inverter outer circumferential flow path 98 are flow paths that substantially overlap with the duct flow path 123.

[0080] The outer duct 120 may be located at a position away from the tip of the motor fin 79 or the tip of the inverter fin 99 toward the outer periphery. In this configuration, the thickness of the duct flow path 123 in the radial direction RD is greater than the thickness of the outer periphery flow paths 78 and 98. That is, in this configuration, the duct flow path 123 extends further toward the outer periphery than the outer periphery flow paths 78 and 98.

[0081] The EPU 50 has a backflow fan 110. The backflow fan 110 rotates about the motor axis Cm. The backflow fan 110 is provided coaxially with the propeller 20. The backflow fan 110 causes gas to flow in the axial direction AD as the motor 61 is driven. The backflow fan 110 is housed in an outer circumferential duct 120. The backflow fan 110 is provided between the motor housing 70 and the gear housing 105 in the axial direction AD.

[0082] The backflow fan 110 is mounted on the motor shaft 65. Therefore, the backflow fan 110 is mounted coaxially with the motor shaft 65. The backflow fan 110 rotates together with the motor shaft 65. Therefore, the backflow fan 110 rotates in synchronization with the rotation of the motor 61. The backflow fan 110 has backflow blades 111. The backflow blades 111 are mounted on the motor shaft 65. The backflow blades 111 extend radially outward from the motor shaft 65. A plurality of backflow blades 111 are arranged in the circumferential direction CD. The plurality of backflow blades 111 are connected by the motor shaft 65.

[0083] The reverse flow fan 110 flows gas in the opposite direction to the propeller 20 in the axial direction AD. In the propulsion device 15, a reverse outer peripheral wind W1 is generated as the reverse flow fan 110 rotates. The reverse outer peripheral wind W1 is a flow of gas, such as outside air. The reverse outer peripheral wind W1 flows through the duct flow path 123 in the axial direction AD along the motor axis Cm. The reverse outer peripheral wind W1 flows in the opposite direction to the propeller wind Wp in the axial direction AD. For example, the reverse outer peripheral wind W1 flows from the EPU 50 toward the propeller 20 in the axial direction AD. The reverse outer peripheral wind W1 flows into the duct flow path 123 from the second duct port 122 and flows out of the outer peripheral duct 120 from the first duct port 121. The reverse outer peripheral wind W1 passes through the duct flow path 123 in the axial direction AD, thereby passing through the outer peripheral flow paths 78, 98 in the axial direction AD. The reverse outer peripheral airflow W1 is fresh air that is newly taken into the duct flow path 123 from outside the EPU 50.

[0084] In the reverse flow fan 110, the rotation direction of the reverse flow fan 110 and the orientation of the reverse flow blades 111 are set so that the reverse outer peripheral wind W1 flows in the opposite direction to the propeller wind Wp. For example, in the reverse flow fan 110, the rotation direction of the reverse flow fan 110 is the same as the rotation direction of the propeller 20, while the orientation of the reverse flow blades 111 is opposite to the orientation of the propeller blades 21. In the reverse flow fan 110, the orientation in which the reverse flow blades 111 are inclined in the circumferential direction CD with respect to the motor axis Cm is opposite to the orientation in which the propeller blades 21 are inclined in the circumferential direction CD with respect to the motor axis Cm. With respect to the reverse outer peripheral wind W1, the EPU 50 is on the upwind side of the propeller 20.

[0085] In the motor device 60, gas flows through the motor space 171. A reverse internal wind W2 flows through the motor space 171 as the reverse flow fan 110 rotates. The reverse internal wind W2 is a flow of gas such as outside air. By flowing through the motor space 171, the reverse internal wind W2 can release heat and the like from the motor 61 to the outside of the motor device 60. The reverse internal wind W2 is fresh air that is newly taken into the motor space 171 from outside the EPU 50.

[0086] The motor housing 70 has a motor inlet hole 175 and a motor outlet hole 176. The motor inlet hole 175 is a hole for allowing gas to flow into the motor space 171. For example, reverse internal wind W2 flows into the motor space 171 through the motor inlet hole 175. The motor inlet hole 175 penetrates the motor outer wall 74 so as to open the motor space 171 to the outside of the motor housing 70. The motor inlet hole 175 opens the motor space 171 toward the downwind side of the propeller wind Wp. The motor inlet hole 175 corresponds to a housing inlet hole. The motor space 171 is a space for introducing gas into the inside of the motor housing 70. The motor space 171, the motor inlet hole 175, and the motor outlet hole 176 are sometimes referred to as an inner introduction portion.

[0087] With respect to the propeller wind Wp, the second motor-facing wall 73b is provided downstream of the first motor-facing wall 73a. The motor inlet hole 175 is provided in the second motor-facing wall 73b. The motor inlet hole 175 penetrates the first motor-facing wall 73a in the axial direction AD. The motor inlet hole 175 spans between the motor-facing outer surface 76b and the motor-facing inner surface 77b of the first motor-facing wall 73a.

[0088] The motor inlet hole 175 is provided in the center of the first motor facing wall 73a. The motor inlet hole 175 is located away from the motor outer peripheral outer surface 76a and the duct flow path 123 toward the inner periphery. The motor inlet hole 175 is also located away from the motor outer peripheral wall 71 toward the inner periphery. That is, the motor inlet hole 175 is located away from the motor outlet hole 176 toward the inner periphery in the radial direction RD. The motor inlet hole 175 is located closer to the motor axis Cm than the motor outer peripheral outer surface 76a in the radial direction RD. That is, the distance between the motor inlet hole 175 and the motor axis Cm is smaller than the distance between the motor outlet hole 176 and the motor axis Cm in the radial direction RD.

[0089] The motor outlet hole 176 is a hole for allowing gas to flow from the motor space 171 to the outside of the motor housing 70. For example, the reverse internal airflow W2 flows from the motor space 171 through the motor outlet hole 176. The motor outlet hole 176 penetrates the motor outer wall 74 to open the motor space 171 to the outside of the motor housing 70. The motor outlet hole 176 opens the motor space 171 toward the duct flow path 123. The motor outlet hole 176 connects the motor space 171 and the duct flow path 123 in a manner that allows ventilation. The motor outlet hole 176 corresponds to a housing outlet hole. The motor outlet hole 176 also serves as an exhaust hole for discharging heat from the motor 61 to the outside.

[0090] The backflow fan 110 blows the reverse internal wind W2 from the motor space 171 through the motor outlet hole 176 and into the duct flow path 123. The backflow fan 110 blows air so that gas flows. The backflow fan 110 corresponds to a blower fan. The outer periphery duct 120 covers the motor outlet hole 176 from the outside so that the motor outlet hole 176 is not exposed to the outer periphery. The outer periphery duct 120 corresponds to an outer duct.

[0091] The motor outlet holes 176 are provided in the motor outer peripheral wall 71. The motor outlet holes 176 penetrate the motor outer peripheral wall 71 in the radial direction RD. The motor outlet holes 176 are arranged across the motor outer peripheral outer surface 76a and the motor outer peripheral inner surface 77a in the motor outer peripheral wall 71. Multiple motor outlet holes 176 are arranged in the circumferential direction CD (see FIG. 4). The motor outlet holes 176 are arranged in the axial direction AD on the motor fins 79. Multiple motor outlet holes 176 are arranged in the axial direction AD. The motor fins 79 are provided between two motor outlet holes 176 adjacent to each other in the axial direction AD.

[0092] As shown in Figures 3 and 5, the motor device 60 has a motor seal 181. The motor seal 181 is provided in the motor housing 70 in a state in which it can open and close the motor outlet hole 176. The motor seal 181 is formed of a valve member, an opening / closing member, a lip seal, or the like. A motor seal 181 is provided individually for each of the multiple motor outlet holes 176. Similar to the motor outlet holes 176, multiple motor seals 181 are arranged in the circumferential direction CD (see Figure 4).

[0093] The motor seal 181 can be shifted between a closed state S1 in which the motor outlet hole 176 is closed and an open state S2 in which the motor outlet hole 176 is open. When the motor seal 181 is in the closed state S1, it restricts ventilation through the motor outlet hole 176. In this case, the motor seal 181 restricts reverse internal wind W2 from flowing out from the motor outlet hole 176 to the duct flow path 123. The closed state S1 of the motor seal 181 corresponds to a restricting state. The motor seal 181 corresponds to an outflow restriction portion.

[0094] When the motor seal 181 is in the open state S2, it opens the motor outlet hole 176 to allow ventilation through the motor outlet hole 176. In this case, the motor seal 181 allows the reverse internal wind W2 to flow from the motor outlet hole 176 into the duct flow path 123. The open state S2 of the motor seal 181 corresponds to the permitted state.

[0095] The motor seal 181 is made of a resin material, a rubber material, or the like and is elastically deformable. The motor seal 181 has an airtight property that blocks airflow. The motor seal 181 covers the motor outlet hole 176 from the duct flow path 123 side. The motor seal 181 is fixed to the motor outer wall 74 in a state that can be switched between a closed state S1 and an open state S2. The motor seal 181 extends along the motor outer surface 76 so as to cover the motor outlet hole 176.

[0096] The motor seal 181 has a first seal end 181a and a second seal end 181b (see FIG. 4). Of the pair of ends of the motor seal 181 aligned in the axial direction AD, the end on the propeller 20 side is the first seal end 181a, and the end opposite the propeller 20 is the second seal end 181b. The first seal end 181a is a fixed end fixed to the motor outer wall 74. The second seal end 181b is a free end not fixed to the motor outer wall 74. The motor seal 181 transitions from the closed state S1 to the open state S2 by elastically deforming the second seal end 181b so that it moves away from the motor outer surface 76 toward the outer periphery. The motor seal 181 corresponds to an elastic regulating portion.

[0097] When external forces are applied to the motor seal 181 by the reverse outer peripheral wind W1 or the reverse internal wind W2, the motor seal 181 elastically deforms to transition from the closed state S1 to the open state S2. For example, when the reverse internal wind W2 pushes the motor seal 181 toward the outer periphery, the motor seal 181 transitions from the closed state S1 to the open state S2 due to the pressing force of the reverse internal wind W2. When the pressing force of the reverse internal wind W2 becomes smaller than the restoring force of the motor seal 181, the motor seal 181 transitions from the open state S2 to the closed state S1 due to its own restoring force.

[0098] In the motor housing 70, when the internal pressure becomes higher than the external pressure to the extent that the motor seal 181 elastically deforms, the internal pressure causes the motor seal 181 to transition from the closed state S1 to the open state S2. The internal pressure is the pressure of the gas in the motor space 171. The external pressure is the pressure of the gas in the duct flow path 123. When the internal pressure decreases to the extent that the motor seal 181 exerts its restoring force, the motor seal 181 transitions from the open state S2 to the closed state S1 due to its own restoring force.

[0099] When the flow of the reverse peripheral wind W1 is strong, the reverse peripheral wind W1 acts on the motor seal 181 with a force that draws the motor seal 181 toward the duct flow path 123, causing the motor seal 181 to transition from the closed state S1 to the open state S2. In this case, the reverse peripheral wind W1 is likely to draw gas from the motor space 171 through the motor outlet hole 176 as the reverse internal wind W2. The strength of the reverse peripheral wind W1 is determined by the amount and speed of the reverse peripheral wind W1. An example of a strong flow of the reverse peripheral wind W1 is when the amount and speed of the reverse peripheral wind W1 are so great that the motor seal 181 transitions from the closed state S1 to the open state S2. When the flow of the reverse peripheral wind W1 weakens, the motor seal 181 transitions from the open state S2 to the closed state S1 due to its own restoring force.

[0100] Furthermore, when the flow of the reverse outer peripheral wind W1 is strong, the reverse outer peripheral wind W1 turns over the motor seal 181 so as to lift the second seal end 181b from the motor outer surface 76, causing the motor seal 181 to transition from the closed state S1 to the open state S2. Even in this case, the reverse outer peripheral wind W1 draws the reverse internal wind W2 from the motor outlet hole 176, causing the reverse internal wind W2 to flow.

[0101] In the EPU 50, the reverse internal wind W2 flows from the motor inlet hole 175 through the internal space of the motor shaft 65 into the motor space 171. The motor shaft 65 is formed in a cylindrical shape as a whole. The motor shaft 65 has a shaft space 165. The shaft space 165 is the internal space of the motor shaft 65. The motor space 171 is open to the outside of the EPU 50 through the shaft space 165.

[0102] As shown in Figure 5, the motor shaft 65 is formed in an overall cylindrical shape. The motor shaft 65 has a shaft outer wall 161 and a shaft flange 162. The shaft outer wall 161 is the outer wall of the motor shaft 65. The shaft outer wall 161 forms the outer and inner surfaces of the motor shaft 65. The shaft outer wall 161 forms a shaft space 165. The shaft outer wall 161 extends in a wall-like shape along the outer and inner surfaces of the motor shaft 65.

[0103] The shaft outer wall 161 has a shaft outer peripheral wall 161a and a shaft end wall 161b. The shaft outer peripheral wall 161a is the outer peripheral wall of the motor shaft 65. The shaft outer peripheral wall 161a is a portion of the shaft outer wall 161 that extends in a direction perpendicular to the radial direction RD. The shaft outer wall 161 is formed in a cylindrical shape. The shaft outer wall 161 extends in the axial direction AD along the motor axis Cm. The shaft end wall 161b is an end wall of the motor shaft 65. The shaft end wall 161b forms the end face of the motor shaft 65. The shaft end wall 161b extends in a direction perpendicular to the axial direction AD. The shaft end wall 161b forms the end of a pair of ends of the motor shaft 65 that is opposite the propeller 20.

[0104] The shaft flange 162 extends from the shaft outer wall 161 toward the outer periphery. The shaft flange 162 is provided on the shaft outer periphery wall 161a. The shaft flange 162 extends in the circumferential direction CD along the shaft outer periphery wall 161a. The shaft flange 162 supports the motor rotor 64. The shaft flange 162 is fixed to the motor rotor 64 with fasteners such as bolts. The shaft flange 162 is provided in the motor space 171.

[0105] The motor shaft 65 penetrates the motor housing 70 in the axial direction AD. A reverse flow fan 110 is provided on the motor shaft 65 at a portion extending from the motor housing 70 toward the propeller 20. Furthermore, at least the shaft end wall 161b of the motor shaft 65 is exposed to the outside of the motor housing 70 through the motor inlet hole 175. For example, in the motor shaft 65, the shaft outer wall 161 is recessed into the motor inlet hole 175. In the shaft outer wall 161, the shaft end wall 161b blocks the motor inlet hole 175. The shaft end wall 161b corresponds to the shaft exposed portion. The shaft outer peripheral wall 161a extends from the shaft end wall 161b in the axial direction AD. The shaft outer peripheral wall 161a corresponds to the shaft extension portion.

[0106] The motor shaft 65 has a shaft inlet hole 166 and a shaft outlet hole 167. The shaft inlet hole 166 and the shaft outlet hole 167 are provided in the shaft outer wall 161. The shaft inlet hole 166 is provided in the shaft end wall 161b. The shaft inlet hole 166 penetrates the shaft end wall 161b in the axial direction AD. The shaft inlet hole 166 is provided in a portion of the motor outer wall 74 that is exposed to the outside of the motor housing 70. The shaft inlet hole 166 opens the shaft space 165 to the outside of the motor housing 70. Gas flowing into the shaft space 165 through the shaft inlet hole 166 flows into the motor space 171 through the motor inlet hole 175. The motor inlet hole 175 indirectly opens the motor space 171 toward the downwind side of the propeller wind Wp via the shaft space 165.

[0107] The shaft inlet hole 166 and the motor inlet hole 175 are open to the outside of the EPU 50 via the inverter housing hole 95. The shaft inlet hole 166 and the motor inlet hole 175 are aligned with the inverter housing hole 95 in the axial direction AD. The shaft inlet hole 166 connects the internal space of the inverter housing hole 95 and the shaft space 165 in a manner that allows ventilation. The reverse internal air W2 passes through the inverter housing hole 95 and flows from the shaft inlet hole 166 into the shaft space 165. The motor inlet hole 175 connects the internal space of the inverter housing hole 95 and the motor space 171 in a manner that allows ventilation. The reverse internal air W2 passes through the inverter housing hole 95 and flows from the motor inlet hole 175 into the motor space 171.

[0108] The shaft outer wall 161 may or may not protrude from the second motor-facing wall 73 b in the axial direction AD. In a configuration in which the shaft outer wall 161 protrudes from the second motor-facing wall 73 b in the axial direction AD, the shaft inlet hole 166 may be provided in at least one of the shaft outer circumferential wall 161 a and the shaft end wall 161 b.

[0109] The shaft outlet holes 167 are provided in the shaft outer peripheral wall 161a. The shaft outlet holes 167 penetrate the shaft outer peripheral wall 161a in the radial direction RD. The shaft outlet holes 167 are provided in a portion of the motor outer wall 74 that is accommodated in the motor space 171. The shaft outlet holes 167 open the shaft space 165 to the motor space 171. In other words, the shaft outlet holes 167 connect the shaft space 165 and the motor space 171 in a manner that allows air to pass through. A plurality of the shaft outlet holes 167 are arranged in the circumferential direction CD. A plurality of the shaft outlet holes 167 are arranged in the axial direction AD. For example, the shaft outlet holes 167 are provided in the shaft outer peripheral wall 161a at a portion closer to the first motor facing wall 73a than the shaft flange 162 and at a portion closer to the second motor facing wall 73b than the shaft flange 162. The reverse internal wind W2 that flows into the shaft space 165 through the shaft inlet hole 166 flows out into the motor space 171 through the shaft outlet hole 167.

[0110] As shown in FIG. 3 , the EPU 50 has an air filter 185. The air filter 185 allows gas to pass through while removing foreign matter such as water, dust, and dirt from the gas. For example, the air filter 185 allows the reverse internal wind W2 to flow into the motor space 171 through the motor inlet hole 175, while restricting foreign matter from flowing into the motor space 171 along with the reverse internal wind W2 through the motor inlet hole 175. The air filter 185 is formed in a sheet shape using a filter material such as nonwoven fabric. The air filter 185 corresponds to a foreign matter restriction portion. The air filter 185 is sometimes referred to as a dust filter.

[0111] The air filter 185 is provided to cover the motor inlet hole 175 and the shaft inlet hole 166 from the axial direction AD. For example, the air filter 185 covers the motor inlet hole 175 from the axial direction AD via the inverter housing hole 95. The air filter 185 is provided in the inverter housing 90 to cover the inverter housing hole 95 from the side opposite the propeller 20. The air filter 185 is fixed to the inverter facing wall 93 with an adhesive or the like. The air filter 185 extends in a direction perpendicular to the axial direction AD.

[0112] 5, the motor 61 has an axial gap 67. The axial gap 67 is a gap between the motor stator 62 and the motor rotor 64. The axial gap 67 includes a gap between the rotor magnet 149 and the stator coil 62a. The rotor magnet 149 and the stator coil 62a are aligned in the axial direction AD.

[0113] The motor stator 62 has a coil protection portion 62b. The coil protection portion 62b protects the stator coil 62a. The coil protection portion 62b is formed from a resin material or the like and has electrical insulation properties. The coil protection portion 62b covers at least a portion of the stator coil 62a. The coil protection portion 62b fixes the stator coil 62a to the motor housing 70. The coil protection portion 62b extends in the circumferential direction CD along the motor outer circumferential inner surface 77a. The coil protection portion 62b is fixed to the motor outer circumferential inner surface 77a.

[0114] The motor rotor 64 has a magnet holder 140. The magnet holder 140 supports a rotor magnet 149. At least a portion of the rotor magnet 149 is arranged in the axial direction AD with respect to the stator coil 62a via an axial gap 67. The magnet holder 140 is made of a metal material or the like. The magnet holder 140 may also be made of a resin material or the like. The magnet holder 140 as a whole extends in a direction perpendicular to the axial direction AD. The magnet holder 140 as a whole extends in an annular shape in the circumferential direction CD.

[0115] The magnet holder 140 has a holder facing portion 141, a holder extension portion 142, a holder interposition portion 143, and a holder rib 144. The holder facing portion 141 is provided in a position facing the motor stator 62. At least a portion of the holder facing portion 141 is aligned with the motor stator 62 in the axial direction AD. The holder facing portion 141 covers the rotor magnet 149 from the side opposite the stator coil 62a. The holder facing portion 141 extends annularly in the circumferential direction CD.

[0116] The holder interposition portion 143 is provided between the holder opposing portion 141 and the holder extending portion 142. The holder interposition portion 143 connects the holder opposing portion 141 and the holder extending portion 142. A plurality of holder interposition portions 143 are arranged in the circumferential direction CD. A ventilated space is formed between two holder interposition portions 143 adjacent to each other in the circumferential direction CD.

[0117] The holder extension portion 142 extends inward from the holder facing portion 141. The holder extension portion 142 is fixed to the shaft flange 162 with bolts or the like. For example, the holder extension portion 142 is arranged on the shaft flange 162 so as to overlap in the axial direction AD. The holder extension portion 142 extends annularly in the circumferential direction CD.

[0118] The holder rib 144 is a rib provided on the holder facing portion 141. The holder rib 144 protrudes from the holder facing portion 141 in the axial direction AD toward the opposite side of the rotor magnet 149. The holder rib 144 extends in the radial direction RD along the holder facing portion 141. At least a portion of the holder rib 144 is aligned with the rotor magnet 149 in the axial direction AD. A plurality of holder ribs 144 are aligned in the circumferential direction CD (see FIG. 4). The holder rib 144 is provided on the inner circumferential side of the motor outlet hole 176 in the motor space 171. At least a portion of the holder rib 144 is aligned with the motor outlet hole 176 in the radial direction RD.

[0119] When the motor 61 is driven, the holder ribs 144 move in the circumferential direction CD as the motor rotor 64 rotates. In this case, the holder ribs 144 blow air in a direction perpendicular to the circumferential direction CD. That is, the motor rotor 64 blows air so that gas flows in the motor space 171. In the motor space 171, the gas blown by the holder ribs 144 easily flows out from the motor outlet holes 176 into the duct flow path 123. For example, the motor rotor 64 blows air so that the reverse internal air W2 that flows into the motor space 171 from the motor inlet holes 175 flows out from the motor outlet holes 176 into the duct flow path 123. The motor rotor 64 corresponds to a blower fan. The holder ribs 144 correspond to rotor blades. The magnet holder 140 has a blower shape due to the holder ribs 144.

[0120] In the motor device 60, the shaft outlet hole 167 is located on the inner circumferential side of the motor outlet hole 176 via the holder rib 144. In the motor device 60, the reverse internal wind W2 that flows into the motor space 171 from the shaft outlet hole 167 tends to reach the motor outlet hole 176 by traveling toward the outer circumferential side due to the airflow of the holder rib 144, etc. This reverse internal wind W2 flows toward the outer circumferential side along the holder rib 144 between the holder opposing portion 141 and the motor opposing walls 73a, 73b. In the motor space 171, the reverse internal wind W2 also flows through the axial gap 67. After flowing into the motor space 171 from the shaft outlet hole 167, the reverse internal wind W2 passes between the holder interposition portions 143 adjacent in the circumferential direction CD, reaches the axial gap 67, and passes through the axial gap 67 toward the outer circumferential side.

[0121] The motor device 60 has a dehumidifying unit 69. The dehumidifying unit 69 is provided inside the motor housing 70. The dehumidifying unit 69 is made of a material such as zeolite or silica gel, and has a dehumidifying function. The dehumidifying unit 69 is capable of removing moisture and humidity from the motor space 171. The dehumidifying unit 69 is also capable of preventing condensation from forming inside the motor housing 70. The dehumidifying unit 69 is fixed to the motor inner surface 77, etc.

[0122] Next, the relationship between the drive state of the propulsion device 15 and the behavior of a foreign object will be described. Here, water droplets DW are assumed as the foreign object. In FIG. 6 , it is assumed that the eVTOL 10 is in a first situation. In the first situation, the angle of the propulsion device 15 is the lift angle, and the drive of the propulsion device 15 is stopped. Therefore, in the first situation, no propeller wind Wp is generated. Furthermore, in the first situation, the eVTOL 10 is not moving, and therefore no movement wind Wm is generated. The lift angle is the angle at which the propulsion device 15 lifts the eVTOL 10. At the lift angle, the propeller axis Cp extends in the vertical direction. Examples of situations in which the eVTOL 10 is not moving include when the eVTOL 10 is on the ground or when the eVTOL 10 is hovering.

[0123] In the first situation, the propulsion unit 15 is not driven, so the reverse flow fan 110 is not rotating, and no reverse outer circumferential wind W1 or reverse inner circumferential wind W2 is generated. Therefore, the motor seal 181 is in the closed state S1. In the first situation, assume that water droplets DW, such as rainwater, fall toward the propulsion unit 15. In this case, even if the water droplets DW enter the duct flow path 123 from the first duct opening 121, the motor seal 181 prevents the water droplets DW from entering the motor space 171 from the motor outlet hole 176.

[0124] Figure 7 illustrates a situation in which the eVTOL 10 is in a second state. In the second state, the angle of the propulsion device 15 is the lift angle, and the propulsion device 15 is driven. In the second state, the propeller wind Wp flows downward, while the reverse outer wind W1 flows upward. Furthermore, a reverse internal wind W2 is generated as if pulled by the reverse outer wind W1. In the second state, the eVTOL 10 is lifted upward due to vertical takeoff or the like. Therefore, in the second state, the moving wind Wm flows downward, similar to the propeller wind Wp. Note that the propeller wind Wp is not shown in Figure 7.

[0125] In the second situation, even if water droplets DW flow down toward the first duct opening 121 together with the propeller wind Wp, the reverse outer peripheral wind W1 prevents the water droplets DW from entering the first duct opening 121. For example, water droplets DW flowing down toward the first duct opening 121 are repelled by the reverse outer peripheral wind W1 blown upward from the first duct opening 121. Therefore, even if the motor seal 181 transitions to the open state S2 due to the reverse outer peripheral wind W1, the water droplets DW are less likely to enter the motor space 171 from the motor outlet hole 176. Furthermore, the reverse internal wind W2 flows upward like the reverse outer peripheral wind W1, passing through the air filter 185 and flowing into the motor space 171 from the motor inlet hole 175.

[0126] FIG. 8 illustrates a case in which the eVTOL 10 is in a third situation. In the third situation, the angle of the propulsion device 15 is the cruise angle, and the propulsion device 15 is driven. Therefore, in the third situation, the propeller wind Wp and the reverse outer peripheral wind W1 flow horizontally in opposite directions. The cruise angle is the angle at which the propulsion device 15 cruises the eVTOL 10. At the cruise angle, the propeller axis Cp extends horizontally. In FIG. 8, the propeller wind Wp is not illustrated. Also, in the third situation, the reverse inner wind W2 is generated as if pulled by the reverse outer peripheral wind W1. In the third situation, the eVTOL 10 is moving toward the propeller 20. Therefore, in the third situation, the moving wind Wm flows horizontally in the same direction as the propeller wind Wp. Examples of situations in which the eVTOL 10 is moving include when the eVTOL 10 is cruising or when the eVTOL 10 is moving on the ground. The moving wind Wm that occurs as the eVTOL 10 cruises is sometimes called a cruising wind.

[0127] In the third situation, even if water droplets DW fly horizontally toward the first duct opening 121 together with the propeller wind Wp or the moving wind Wm, similar to the second situation, the reverse outer peripheral wind W1 prevents the water droplets DW from entering the first duct opening 121. In the third situation, even if the angle of the propulsion device 15 is the cruise angle, the reverse outer peripheral wind W1 transitions the motor seal 181 to the open state S2 against gravity and the like.

[0128] 9 assumes that the eVTOL 10 is in a fourth situation. In the fourth situation, the angle of the propulsion device 15 is the cruise angle, and the drive of the propulsion device 15 is stopped. Therefore, in the fourth situation, the propeller wind Wp, the reverse outer peripheral wind W1, and the reverse inner wind W2 are not generated. Also, in the fourth situation, the eVTOL 10 is cruising so as to move toward the propeller 20. Therefore, in the fourth situation, the moving wind Wm flows horizontally.

[0129] In the fourth situation, when water droplets DW fly toward the first duct opening 121 together with the moving wind Wm, the water droplets DW enter the duct flow path 123 from the first duct opening 121 together with the moving wind Wm and exit from the second duct opening 122. In the fourth situation, since the reverse outer peripheral wind W1 is not generated, the motor seal 181 is maintained in the closed state S1 against gravity and the like. Therefore, the motor seal 181 prevents the water droplets DW from entering the motor space 171 from the motor outlet hole 176.

[0130] 10 assumes that the eVTOL 10 is in the fifth situation. In the fifth situation, the angle of the propulsion device 15 is the cruise angle, and the drive of the propulsion device 15 is stopped. Also, in the fifth situation, the eVTOL 10 is not moving. Therefore, in the fifth situation, as in the first situation, none of the propeller wind Wp, the moving wind Wm, the reverse outer peripheral wind W1, and the reverse internal wind W2 are generated.

[0131] In the fifth situation, even if the water droplets DW fall toward the EPU 50, the water droplets DW hit the outer peripheral surface of the outer duct 120. Therefore, the water droplets DW are unlikely to enter the duct flow path 123 or the motor space 171 from the motor outlet hole 176.

[0132] According to the present embodiment described so far, the duct flow path 123 is provided outside the motor inner surface 77. In this configuration, heat from the motor 61 is released to the duct flow path 123 via the motor housing 70. Therefore, the heat dissipation effect of the motor housing 70 can be enhanced by gases such as the reverse outer peripheral airflow W1 flowing through the duct flow path 123. Furthermore, in the motor housing 70, the duct flow path 123 and the motor space 171 are connected by the motor outlet hole 176. In this configuration, heat from the motor 61 is easily released, together with gases such as the reverse inner airflow W2, from the motor space 171 through the motor outlet hole 176 to the duct flow path 123. Therefore, the motor outlet hole 176 and the duct flow path 123 can prevent heat from building up inside the motor housing 70. As described above, the motor outlet hole 176 and the duct flow path 123 can enhance the heat dissipation effect of the propulsion device 15.

[0133] According to this embodiment, the motor inlet hole 175 opens the motor space 171 to the outside of the motor housing 70. In this configuration, the reverse internal wind W2 flows from the outside of the motor housing 70 into the motor space 171, and this reverse internal wind W2 promotes heat dissipation from the motor 61. Therefore, the motor inlet hole 175 can enhance the heat dissipation effect of the propulsion device 15.

[0134] According to this embodiment, the air filter 185 allows gas to flow into the motor inlet hole 175 while restricting foreign matter from entering the motor space 171 through the motor inlet hole 175. In this configuration, the air filter 185 can prevent foreign matter from entering the motor space 171 through the motor inlet hole 175 and causing abnormalities in the motor 61, etc. Therefore, the reverse internal airflow W2 can be introduced into the motor space 171 to directly cool the motor 61 without impairing the operation of the motor 61.

[0135] According to this embodiment, the motor housing 70 has a motor outlet hole 176 formed in the motor outer peripheral wall 71. In this configuration, when the reverse outer peripheral airflow W1 flows in the axial direction AD along the motor outer peripheral wall 71, the reverse outer peripheral airflow W1 tends to draw the reverse internal airflow W2 from the motor outlet hole 176 into the duct flow path 123, which makes it easier for the reverse internal airflow W2 to be generated. This allows for a configuration in which the heat of the motor 61, together with the reverse internal airflow W2, is directly released to the outside from the motor outlet hole 176.

[0136] Furthermore, the motor housing 70 has a motor inlet hole 175 formed in the second motor-facing wall 73b. With this configuration, the reverse internal air W2 flows directly into the motor space 171 from the motor inlet hole 175 without passing through the duct flow path 123. In other words, the reverse internal air W2 is introduced into the motor space 171 as fresh air. This enhances the cooling effect of the motor 61 by the reverse internal air W2.

[0137] In this embodiment, the motor outlet hole 176 is provided at a position in the motor housing 70 where the motor axis Cm passes. In this configuration, the reverse internal wind W2 flows toward the center of the motor space 171. This makes it easier for the reverse internal wind W2 to flow evenly inside the motor housing 70. In other words, the reverse internal wind W2 tends to flow throughout the entire motor space 171. Therefore, the reverse internal wind W2 can prevent heat from building up in one part of the motor space 171.

[0138] According to this embodiment, the motor inlet hole 175 opens the motor space 171 toward the downwind side of the propeller wind Wp. With this configuration, it is unlikely that the propeller wind Wp will flow directly into the motor inlet hole 175. This makes it possible to prevent foreign matter from entering the motor space 171 from the motor inlet hole 175 along with the propeller wind Wp.

[0139] According to this embodiment, in the motor shaft 65, the shaft inlet hole 166 opens the shaft space 165 to the outside of the motor shaft 65, and the shaft outlet hole 167 connects the shaft space 165 to the motor space 171. In this configuration, the reverse internal air W2 that flows into the motor space 171 from the motor inlet hole 175 passes through the shaft space 165, then passes through the motor space 171, and flows out from the motor outlet hole 176 to the duct flow path 123. As a result, heat from the motor shaft 65 is released to the outside of the motor housing 70 together with the reverse internal air W2. Therefore, the reverse internal air W2 can prevent heat from building up inside the motor shaft 65.

[0140] In this embodiment, the shaft inlet hole 166 is provided in a portion of the motor shaft 65 that is exposed to the outside of the motor housing 70. This allows the reverse internal wind W2 that flows in from the shaft inlet hole 166 to flow through the shaft space 165 and pass through the motor inlet hole 175. With this configuration, even if the motor inlet hole 175 is blocked by the motor shaft 65, the reverse internal wind W2 is introduced into the motor space 171 through the motor inlet hole 175. Therefore, there is no need to form a gap between the second motor facing wall 73b and the motor shaft 65 at the motor inlet hole 175 to allow the reverse internal wind W2 to flow into the motor space 171.

[0141] According to this embodiment, the motor seal 181 can be transitioned between a closed state S1 in which the motor outlet hole 176 is closed and an open state S2 in which the motor outlet hole 176 is open. In this configuration, when the motor seal 181 is in the open state S2, heat in the motor space 171 can be released from the motor outlet hole 176 together with the reverse internal airflow W2. Furthermore, when the motor seal 181 is in the closed state S1, the motor seal 181 can prevent foreign matter from entering the motor space 171 through the motor outlet hole 176. In this way, the motor seal 181 can both prevent abnormalities in the motor 61 caused by foreign matter entering the motor space 171 and improve the cooling performance of the motor space 171 by the reverse internal airflow W2.

[0142] According to this embodiment, the motor seal 181 transitions from the closed state S1 to the open state S2 by elastically deforming due to the flow of the reverse outer peripheral wind W1 in the duct flow path 123, and transitions from the open state S2 to the closed state S1 due to a restoring force that resists the flow of the reverse outer peripheral wind W1. In this configuration, the motor seal 181 is likely to open and close depending on the strength of the flow of the reverse outer peripheral wind W1, etc. Therefore, by utilizing the elastic deformation and restoring force of the motor seal 181, a configuration can be realized in which the motor seal 181 opens and closes in accordance with the drive state of the propulsion device 15.

[0143] According to this embodiment, the reverse flow fan 110 blows air such that the reverse internal wind W2 flows from the motor space 171 through the motor outlet hole 176 and into the duct flow path 123. In this configuration, the reverse flow fan 110 can forcibly flow the reverse outer peripheral wind W1 into the duct flow path 123. Therefore, the reverse flow fan 110 can exert the cooling effect of the motor housing 70 by the reverse outer peripheral wind W1 without relying on the propeller wind Wp or the moving wind Wm.

[0144] In this embodiment, the backflow fan 110 is attached coaxially to the motor shaft 65 so that the rotation of the backflow fan 110 is synchronized with the rotation of the motor shaft 65. In other words, the backflow fan 110 is provided integrally with the motor shaft 65. With this configuration, the backflow fan 110 does not need to be provided separately from the motor shaft 65. In other words, there is no need to add a dedicated mechanism, such as a dedicated shaft, to the motor device 60 in order to add the backflow fan 110 to the motor device 60. As a result, the weight of the motor device 60 can be reduced, and the cooling effect of the motor device 60 can be improved by the backflow fan 110.

[0145] In this embodiment, the backflow fan 110 is provided on the outside of the motor housing 70 so as to flow the reverse outer peripheral wind W1. Therefore, when the reverse outer peripheral wind W1 is generated as the backflow fan 110 rotates, a configuration can be realized in which the reverse internal wind W2 is also generated as it is pulled by the reverse outer peripheral wind W1. Therefore, the backflow fan 110 can stably generate a state in which the cooling airs, namely the reverse outer peripheral wind W1 and the reverse internal wind W2, flow in both the duct flow path 123 and the motor space 171.

[0146] According to this embodiment, the holder rib 144 blows air so that the reverse internal air W2 flows out from the motor outlet hole 176 into the duct flow path 123 as the motor rotor 64 rotates. In this configuration, the holder rib 144, which is part of the motor rotor 64, is used to generate the reverse internal air W2 in the motor space 171. In this way, by having the motor rotor 64 function as a blower fan, the heat dissipation effect of the motor device 60 can be improved.

[0147] In this embodiment, the holder ribs 144, which function as air blower blades for blowing air, extend from the motor rotor 64 toward the opposite side of the motor stator 62. That is, the holder ribs 144 are provided on the opposite side of the axial gap 67 across the rotor magnet 149. In the motor rotor 64, the area on the opposite side of the axial gap 67 across the rotor magnet 149, which is less likely to contribute to the generation of motor torque, is used as the installation area for the holder ribs 144. Therefore, the holder ribs 144 functioning as air blower blades can enhance the heat dissipation effect of the motor device 60, while suppressing a decrease in the output performance of the motor 61 due to the holder ribs 144.

[0148] According to this embodiment, the motor outlet holes 176 are provided on the outer periphery of the holder ribs 144, which function as blower blades. In this configuration, the reverse internal wind W2 generated by the holder ribs 144 as the motor rotor 64 rotates flows from the holder ribs 144 toward the outer periphery, easily flowing from the motor outlet holes 176 into the duct flow path 123. In this manner, the reverse internal wind W2 is blown toward the motor outlet holes 176 by the holder ribs 144, allowing it to reach the motor outlet holes 176 without detouring in the axial direction AD or the circumferential direction CD. This reduces pressure loss in the motor space 171 due to the flow of the reverse internal wind W2. This allows for a configuration in which the reverse internal wind W2 is smoothly discharged from the motor outlet holes 176 into the duct flow path 123.

[0149] Furthermore, in this configuration, the holder rib 144 directs the reverse internal wind W2 toward the motor outlet hole 176, so that the reverse internal wind W2 pushes the motor seal 181 toward the duct flow path 123, thereby opening it. This allows for a configuration in which the motor seal 181 can easily transition from the closed state S1 to the open state S2 as the motor 61 is driven.

[0150] According to this embodiment, the outer periphery duct 120 is attached to the motor housing 70 so as to cover the motor outflow hole 176 from the outside. In this configuration, the outer periphery duct 120 can prevent foreign matter from reaching the motor outflow hole 176. Furthermore, the outer periphery duct 120 extends further in both directions in the axial direction AD than the motor housing 70. In this configuration, when the angle of the propulsion unit 15 reaches the cruise angle, the outer periphery duct 120 acts like an umbrella for the motor housing 70 and the motor outflow hole 176. Therefore, the outer periphery duct 120 can more reliably prevent foreign matter from entering the motor space 171 from the motor outflow hole 176.

[0151] According to this embodiment, the propulsion device 15 is driven to fly the eVTOL 10. In this configuration, when the propulsion device 15 is driving the eVTOL 10 to fly, the reverse outer peripheral wind W1 and reverse internal wind W2 can prevent the motor device 60 from dissipating heat effectively and causing the temperature of the motor 61 to rise excessively. The eVTOL 10 also has a passenger compartment 14. Therefore, the reverse outer peripheral wind W1 and reverse internal wind W2 can improve the safety of the eVTOL 10 and the passengers.

[0152] Second Embodiment In the first embodiment, the propeller wind Wp flows in the axial direction AD from the propeller 20 toward the EPU 50. In contrast, in the second embodiment, the propeller wind Wp flows in the axial direction AD from the EPU 50 toward the propeller 20. Configurations, actions, and effects that are not specifically described in the second embodiment are the same as those in the first embodiment. The second embodiment will be described mainly focusing on the differences from the first embodiment.

[0153] In the eVTOL 10 of this embodiment, the multiple propellers 20 include a lift propeller and a cruise propeller. The lift propeller is included in the propulsion unit 15 mounted on the eVTOL 10 at a lift angle. The driving rotation of the lift propeller enables the eVTOL 10 to ascend, descend, hover, and the like. The cruise propeller is included in the propulsion unit 15 mounted on the eVTOL 10 at a cruise angle. The driving rotation of the cruise propeller enables the eVTOL 10 to cruise, and the like.

[0154] In this embodiment, a propulsion device 15 having a cruise propeller will be described. As shown in FIG. 11 , the propeller 20 is located on the downwind side of the EPU 50 with respect to the propeller wind Wp. The EPU 50 has an EPU head 200. The EPU head 200 is provided on the opposite side of the propeller 20 across the motor device 60 and the inverter device 80. The EPU head 200 is aligned with the motor device 60 and the inverter device 80 in the axial direction AD. The EPU head 200 covers the inverter housing hole 95 and the motor inlet hole 175 from the opposite side of the propeller 20. With respect to the propeller wind Wp, the EPU head 200 is located on the upwind side of the motor device 60 and the inverter device 80. The EPU head 200 corresponds to a cover member. The EPU head 200 is sometimes referred to as a nacelle.

[0155] The EPU head 200 has a head outer wall 201. The head outer wall 201 forms the outer and inner surfaces of the EPU head 200. The head outer wall 201 as a whole extends in a direction perpendicular to the axial direction AD. The head outer wall 201 has a shape that bulges outward toward the side opposite the motor device 60. The head outer wall 201 is curved such that a central portion of the head outer wall 201 protrudes in the axial direction AD. The head outer wall 201 covers the inverter housing hole 95 and the motor inlet hole 175 from the axial direction AD. At least the tip of the head outer wall 201 is positioned inside the outer circumferential duct 120. The end of the head outer wall 201 on the propeller 20 side is housed in the outer circumferential duct 120.

[0156] A head hole 202 is provided in the head outer wall 201. The head hole 202 penetrates the head outer wall 201 in the thickness direction of the head outer wall 201. The head hole 202 penetrates in the radial direction RD at a portion of the head outer wall 201 that extends in a direction perpendicular to the radial direction RD. A plurality of head holes 202 are arranged in the circumferential direction CD. The head holes 202 are covered from the outer periphery by the outer periphery duct 120. Note that the head hole 202 does not have to be covered by the outer periphery duct 120. For example, the head hole 202 may be provided at a position spaced apart from the outer periphery duct 120 in the axial direction AD.

[0157] The EPU head 200 has a head flow path 205. The head flow path 205 is included in the internal space of the EPU head 200. The head flow path 205 is open to the outside of the EPU head 200 by a head hole 202. The head flow path 205 connects the head hole 202 and the inverter housing hole 95 so that air can flow between them. The head flow path 205 is a passage for gas. The head flow path 205 extends in the radial direction RD so as to bridge between the head hole 202 and the inverter housing hole 95. The head flow path 205 is located adjacent to the head outer wall 201 in the axial direction AD. The head flow path 205 may be included in an inner introduction portion.

[0158] Unlike the first embodiment, the EPU 50 does not have a reverse flow fan 110. In the propulsion device 15, a forward outer peripheral wind W3 is generated in conjunction with the generation of a propeller wind Wp. The forward outer peripheral wind W3 is a flow of gas, such as outside air. The forward outer peripheral wind W3 passes through the duct flow path 123 in the axial direction AD. The forward outer peripheral wind W3 flows in the same direction as the propeller wind Wp in the axial direction AD. The forward outer peripheral wind W3 is the wind, including the propeller wind Wp and the moving wind Wm, that flows through the duct flow path 123. The forward outer peripheral wind W3 flows into the duct flow path 123 from the second duct port 122 and flows out from the first duct port 121.

[0159] In the motor device 60, a forward internal wind W4 may be generated in conjunction with the generation of the forward peripheral wind W3. The forward internal wind W4 flows from the head hole 202 into the head flow path 205, passes through the air filter 185, the inverter housing hole 95, and the shaft space 165, and flows into the motor space 171. The forward internal wind W4 then flows from the motor space 171 through the motor outlet hole 176 and into the duct flow path 123. The forward internal wind W4 is generated by the propeller wind Wp and the forward peripheral wind W3, and flows through the motor space 171.

[0160] Unlike the first embodiment, the EPU 50 includes a plurality of motor devices 60. The plurality of motor devices 60 are arranged in the axial direction AD. For example, the plurality of motor devices 60 are provided between the inverter device 80 and the propeller 20.

[0161] In this embodiment, the motor device 60 and the gear device 100 are positioned adjacent to each other in the axial direction AD without the reverse flow fan 110 in between. In the motor housing 70, the first motor facing wall 73a overlaps the gear facing wall 107. When the forward internal wind W4 flows through the motor space 171, the forward internal wind W4 flows toward the outer periphery between the holder facing portion 141 and the first motor facing wall 73a, and thereby flows toward the outer periphery along the gear facing wall 107 via the first motor facing wall 73a.

[0162] In the motor device 60, heat from the gear device 100 is likely to be released through the first motor-facing wall 73a into the forward internal airflow W4 flowing between the motor rotor 64 and the first motor-facing wall 73a. In particular, the forward internal airflow W4 flowing into the motor space 171 from the shaft outlet hole 167 between the motor rotor 64 and the first motor-facing wall 73a in the axial direction AD is thought to flow into the motor space 171 with relatively little heat imparted from the motor shaft 65. Therefore, as the forward internal airflow W4 flows through the shaft space 165, it is likely to reach the space between the motor rotor 64 and the first motor-facing wall 73a while maintaining a relatively high cooling effect. Therefore, the forward internal airflow W4 with a relatively high cooling effect can cool the gear-facing wall 107 through the first motor-facing wall 73a. In other words, the forward internal airflow W4 can cool the gear device 100 through the first motor-facing wall 73a.

[0163] 12 illustrates a situation in which the eVTOL 10 is in a sixth state. In the sixth state, the cruise propulsion device 15 is stopped. The eVTOL 10 is also not moving. Therefore, in the sixth state, no propeller wind Wp, no moving wind Wm, no forward outer wind W3, and no forward inner wind W4 are generated. In the sixth state, even if water droplets DW fall toward the eVTOL 10, the outer periphery duct 120 prevents the water droplets DW from entering the motor space 171 through the motor outlet hole 176.

[0164] FIG. 13 illustrates a situation in which the eVTOL 10 is in a seventh situation. In the seventh situation, the cruise propulsion device 15 is operating. Therefore, in the seventh situation, the propeller wind Wp flows horizontally from the EPU 50 toward the propeller 20. The propeller wind Wp is not shown in FIG. 13. In the seventh situation, the eVTOL 10 is moving toward the EPU head 200. Therefore, in the seventh situation, the moving wind Wm flows horizontally in the same direction as the propeller wind Wp. In the seventh situation, the generation of the moving wind Wm and the propeller wind Wp generates a forward outer peripheral wind W3 and a forward inner wind W4.

[0165] In the seventh situation, water droplets DW may fly horizontally toward the EPU head 200 along with the propeller wind Wp and the moving wind Wm. Even if these water droplets DW are traveling toward the motor inlet hole 175, once they reach the EPU head 200, they move along the head outer wall 201 and move away from the motor inlet hole 175 toward the outer periphery. In other words, the EPU head 200 guides the water droplets DW approaching in the axial direction AD so that they move away from the motor inlet hole 175 toward the outer periphery. The water droplets DW guided by the head outer wall 201 then pass horizontally through the duct flow path 123 together with the forward outer periphery wind W3. The head outer wall 201 is sometimes referred to as a rainwater guide portion or a foreign object guide portion.

[0166] In the motor housing 70, the motor seal 181 is in the open state S2 due to the flow of the forward outer peripheral wind W3 and the forward internal wind W4. Even when the motor seal 181 is in the open state S2, the forward internal wind W4 flowing out of the motor outlet hole 176 prevents the water droplets DW from entering the motor space 171 through the motor outlet hole 176 in the duct flow path 123. Also, in the seventh situation, as in the sixth situation, the outer peripheral duct 120 prevents the falling water droplets DW from entering the motor space 171 through the motor outlet hole 176.

[0167] According to this embodiment, the EPU head 200 guides foreign matter away from the motor inlet hole 175 toward the outer periphery. With this configuration, even if the motor inlet hole 175 opens the motor space 171 toward the upstream side of the propeller wind Wp and the moving wind Wm, the EPU head 200 can prevent foreign matter from entering the motor inlet hole 175. Meanwhile, the EPU head 200 covers the motor inlet hole 175 from the axial direction AD so that the forward internal wind W4 flows into the motor inlet hole 175. Therefore, the forward internal wind W4 enhances the heat dissipation effect of the motor space 171, while preventing foreign matter from entering the motor space 171 from the motor inlet hole 175.

[0168] According to this embodiment, the tip of the head outer wall 201 is housed in the outer peripheral duct 120. In this configuration, water droplets DW that reach the head outer wall 201 by traveling in the axial direction AD are guided to the outer periphery by the head outer wall 201, and are therefore likely to enter the duct flow path 123 from the second duct port 122. Due to their own inertia, these water droplets DW tend to pass through the head hole 202 and travel in the axial direction AD through the duct flow path 123 toward the first duct port 121. In this way, by actively guiding the water droplets DW into the duct flow path 123, it is possible to effectively prevent the water droplets DW from entering the head hole 202 and reaching the motor inlet hole 175.

[0169] <Third Embodiment> In the second embodiment, the propulsion device 15 has the outer circumferential duct 120. In contrast, in the third embodiment, the propulsion device 15 does not have an outer duct such as the outer circumferential duct 120. The configurations, actions, and effects of the third embodiment that are not specifically described are the same as those of the second embodiment. The third embodiment will be described mainly focusing on the differences from the second embodiment.

[0170] As shown in FIG. 14 , unlike the second embodiment, the EPU 50 does not have an outer duct 120. In the EPU 50, the motor outer peripheral outer surface 76 a, the inverter outer peripheral outer surface 96 a, the motor fins 79, the inverter fins 99, the head holes 202, and other components are exposed to the outer periphery. In the EPU 50, the forward outer peripheral airflow W3 flows through the inverter outer peripheral flow passage 98 and the motor outer peripheral flow passage 78 in the axial direction AD. In this embodiment, the motor outer peripheral flow passage 78 also corresponds to the outer flow passage. Furthermore, in the EPU 50, the motor seal 181 is exposed to the outer periphery. Even with this configuration, when the motor seal 181 is in the closed position S1 or when the forward internal airflow W4 is flowing out from the motor outlet hole 176, foreign matter is less likely to enter the motor space 171 through the motor outlet hole 176.

[0171] <Fourth Embodiment> In the second embodiment, the outer flow passages such as the duct flow passage 123 are formed outside the motor outer surface 76. In contrast, in the fourth embodiment, the outer flow passages are formed inside the motor outer surface 76. The configurations, actions, and effects of the fourth embodiment that are not specifically described are the same as those of the second embodiment. The fourth embodiment will be described mainly focusing on the differences from the second embodiment.

[0172] As shown in FIG. 15 , the motor housing 70 has a motor-wall internal flow passage 210. The motor-wall internal flow passage 210 is formed in the motor outer wall 74. The motor-wall internal flow passage 210 is provided between the motor outer surface 76 and the motor inner surface 77. The motor-wall internal flow passage 210 is provided outside the motor inner surface 77. For example, the motor-wall internal flow passage 210 is formed in the motor outer peripheral wall 71. The motor-wall internal flow passage 210 is formed between the motor outer peripheral outer surface 76 a and the motor outer peripheral inner surface 77 a. The motor-wall internal flow passage 210 is provided outside the motor outer peripheral inner surface 77 a. The motor-wall internal flow passage 210 extends in the axial direction AD. The motor-wall internal flow passage 210 corresponds to an outer flow passage.

[0173] The motor-wall internal flow passage 210 penetrates the motor outer wall 74 in the axial direction AD. The motor-wall internal flow passage 210 has a first motor-wall port 211 and a second motor-wall port 212. The first motor-wall port 211 and the second motor-wall port 212 are aligned in the axial direction AD. The end of the motor-wall internal flow passage 210 on the propeller 20 side is the first motor-wall port 211, and the end on the opposite side from the propeller 20 is the second motor-wall port 212. The first motor-wall port 211 opens the motor-wall internal flow passage 210 toward the propeller 20 side. The second motor-wall port 212 opens the motor-wall internal flow passage 210 toward the opposite side from the propeller 20.

[0174] The motor outlet hole 176 connects the motor space 171 and the motor wall internal flow path 210 in a manner that allows air to pass through. The motor outlet hole 176 penetrates the motor outer peripheral wall 71 in the radial direction RD through a portion between the motor outer peripheral inner surface 77a and the motor wall internal flow path 210. The motor seal 181 closes the motor outlet hole 176 by covering it from the motor wall internal flow path 210 side. The motor seal 181 is provided in the motor wall internal flow path 210.

[0175] The inverter housing 90 has an inverter wall channel 220. The inverter wall channel 220 is formed in the inverter outer wall 94. The inverter wall channel 220 is provided between the inverter outer surface 96 and the inverter inner surface 97. The inverter wall channel 220 is provided outside the inverter inner surface 97. For example, the inverter wall channel 220 is formed in the inverter outer peripheral wall 91. The inverter wall channel 220 is formed between the inverter outer peripheral outer surface 96a and the inverter outer peripheral inner surface 97a. The inverter wall channel 220 is provided outside the inverter outer peripheral inner surface 97a. The inverter wall channel 220 extends in the axial direction AD.

[0176] The inverter wall flow path 220 penetrates the inverter outer wall 94 in the axial direction AD. The inverter wall flow path 220 has a first inverter wall opening 221 and a second inverter wall opening 222. The first inverter wall opening 221 and the second inverter wall opening 222 are aligned in the axial direction AD. The inverter wall flow path 220 has the first inverter wall opening 221 at its end on the propeller 20 side and the second inverter wall opening 222 at its end on the opposite side from the propeller 20. The first inverter wall opening 221 opens the inverter wall flow path 220 toward the propeller 20 side. The second inverter wall opening 222 opens the inverter wall flow path 220 toward the opposite side from the propeller 20.

[0177] In two motor devices 60 adjacent to each other in the axial direction AD, the respective motor intra-wall flow paths 210 are connected to each other so as to be able to communicate with each other. The boundary between two motor intra-wall flow paths 210 adjacent to each other in the axial direction AD includes a first motor wall port 211 on one side and a second motor wall port 212 on the other side. In two inverter devices 80 adjacent to each other in the axial direction AD, the respective inverter intra-wall flow paths 220 are connected to each other so as to be able to communicate with each other. The boundary between two inverter intra-wall flow paths 220 adjacent to each other in the axial direction AD includes a first inverter wall port 221 on one side and a second inverter wall port 222 on the other side. The motor intra-wall flow paths 210 and the inverter intra-wall flow paths 220 adjacent to each other in the axial direction AD are connected to each other so as to be able to communicate with each other.

[0178] The EPU 50 does not have an outer circumferential duct 120. In this embodiment, even if the EPU 50 does not have an outer circumferential duct 120, the motor-wall inner flow passage 210 is provided as an outer flow passage relative to the motor housing 70. Note that the EPU 50 may also have the outer circumferential duct 120. That is, a duct flow passage 123 may be provided on the outer circumferential side of the motor-wall inner flow passage 210. In this configuration, a plurality of outer flow passages, namely the motor-wall inner flow passage 210 and the duct flow passage 123, are arranged in the radial direction RD.

[0179] The EPU 50 does not have motor fins 79 or inverter fins 99. That is, the EPU 50 does not have a motor outer circumferential flow passage 78 or an inverter outer circumferential flow passage 98. The EPU 50 may have motor fins 79 or inverter fins 99. That is, the EPU 50 may have a motor outer circumferential flow passage 78 or an inverter outer circumferential flow passage 98. In this configuration, multiple outer flow passages, namely, the motor wall inner flow passage 210 and the motor outer circumferential flow passage 78, are arranged in the radial direction RD.

[0180] Fifth Embodiment In the first embodiment, the motor seal 181 transitions from the closed state S1 to the open state S2 due to the generation of the reverse outer peripheral wind W1 or the reverse internal wind W2. In contrast, in the fifth embodiment, the outflow restriction portion such as the motor seal 181 is opened and closed regardless of the presence or absence of the reverse outer peripheral wind W1 or the reverse internal wind W2. The configuration, operation, and effects not specifically described in the fifth embodiment are the same as those in the first embodiment. The fifth embodiment will be described mainly focusing on the differences from the first embodiment.

[0181] As shown in FIG. 16 , the motor device 60 has a drive seal 183. The drive seal 183 is provided in the motor housing 70 in a state in which it can open and close the motor outlet hole 176. The drive seal 183 is formed of a valve member, an opening / closing member, a lip seal, or the like. For example, the drive seal 183 is formed in a seal shape. The drive seal 183 is provided individually for each of the multiple motor outlet holes 176. A plurality of the drive seals 183 are arranged in the circumferential direction CD.

[0182] The drive seal 183, like the motor seal 181 of the first embodiment, can be moved between a closed state S1 and an open state S2. When the drive seal 183 is in the closed state S1, it restricts the flow of air through the motor outlet hole 176. In this case, the drive seal 183 restricts the reverse internal wind W2 from flowing out from the motor outlet hole 176 to the duct flow path 123. The drive seal 183 corresponds to an outflow restriction portion. The drive seal 183 is made of a resin material or the like. The drive seal 183 has an air-blocking property that blocks air from passing through.

[0183] As shown in FIG. 17 , the motor device 60 has a seal drive unit 183a. The seal drive unit 183a is a drive unit for opening and closing the driven seal 183. The seal drive unit 183a is formed by including an actuator such as an electric motor. The seal drive unit 183a drives the driven seal 183 to transition between a closed state S1 and an open state S2. A seal drive unit 183a is provided individually for each of the multiple driven seals 183. In FIG. 17 , the driven seal 183 is illustrated as Valve, and the seal drive unit 183a is illustrated as ACT.

[0184] The seal drive unit 183a is communicatively connected to the inverter control unit 82. The seal drive unit 183a is driven in response to a signal from the inverter control unit 82. The opening and closing of the drive seal 183 is controlled by the inverter control unit 82 via the seal drive unit 183a. The drive seal 183 corresponds to the control restriction unit. The seal drive unit 183a corresponds to the restriction drive unit. In the EPU 50, at least one inverter control unit 82 controls the seal drive unit 183a. The inverter control unit 82 corresponds to the drive control unit. The seal drive unit 183a may be communicatively connected to the flight control device 40. In this configuration, the seal drive unit 183a may be driven in response to a signal from the flight control device 40.

[0185] The EPU 50 has an internal pressure sensor 231, an external pressure sensor 232, a motor rotation sensor 233, and a motor temperature sensor 234. The internal pressure sensor 231 is formed to include a pressure sensor. The internal pressure sensor 231 detects the motor internal pressure. The motor internal pressure is the internal pressure of the motor housing 70. For example, the motor internal pressure is the pressure in the motor space 171. The internal pressure sensor 231 is provided inside the motor housing 70. For example, the internal pressure sensor 231 is provided in the motor space 171. The internal pressure sensor 231 outputs a detection signal corresponding to the motor internal pressure.

[0186] The external pressure sensor 232 is formed to include a pressure sensor. The external pressure sensor 232 detects the motor external pressure. The motor external pressure is the pressure outside the motor housing 70. For example, the motor external pressure is the pressure in the duct flow path 123. The external pressure sensor 232 is provided outside the motor housing 70. For example, the external pressure sensor 232 is provided in the duct flow path 123. The external pressure sensor 232 outputs a detection signal corresponding to the motor external pressure.

[0187] The motor rotation sensor 233 detects the motor rotation speed. The motor rotation speed is the rotation speed of the motor 61. The motor rotation speed is sometimes referred to as the motor rotation speed. The motor rotation sensor 233 is formed by including an encoder, a resolver, etc. The motor rotation sensor 233 is provided in the motor 61. The motor rotation sensor 233 is included in the motor device 60. The motor rotation sensor 233 outputs a detection signal according to the motor rotation speed.

[0188] The motor temperature sensor 234 detects the motor temperature. The motor temperature is the temperature of the motor device 60. The motor temperature may be the temperature of the motor rotor 64, the temperature of the motor stator 62, the temperature of the motor space 171, or the like. The motor temperature sensor 234 is provided inside the motor housing 70. For example, the motor temperature sensor 234 is provided in the motor 61. The motor temperature sensor 234 outputs a detection signal corresponding to the motor temperature.

[0189] The sensors 231 to 234 are communicably connected to the inverter control unit 82. The sensors 231 to 234 output detection signals to the inverter control unit 82. The inverter control unit 82 uses the detection signals of the sensors 231 to 234 to perform EPU control.

[0190] The inverter control unit 82 executes an EPU control process to perform EPU control. The EPU control process will be described with reference to the flowchart of Fig. 18. The inverter control unit 82 repeatedly executes the EPU control process at a predetermined control period.

[0191] Inverter control unit 82 performs information acquisition processing in step S101 shown in Fig. 18. In the information acquisition processing, information related to eVTOL 10 is acquired. Information related to eVTOL 10 includes information related to EPU 50 and information related to motor device 60. Information related to motor device 60 includes information including detection signals from sensors 231-234.

[0192] In step S102, the inverter control unit 82 determines whether or not the motor 61 is in operation. If the motor 61 is in operation, the inverter control unit 82 proceeds to step S103.

[0193] In step S103, the inverter control unit 82 determines whether the drive duration Dm has reached a duration threshold TDm. The drive duration Dm is the time during which the motor 61 continues to drive after it has started to drive. The duration threshold TDm is a value determined in advance through testing or the like, and is stored in the memory 84 or the like. The duration threshold TDm is set to, for example, 1 sec.

[0194] In the propulsion device 15, after the motor 61 starts to operate, the flow of the reverse outer peripheral wind W1 becomes stronger as the motor rotation speed increases. If the flow of the reverse outer peripheral wind W1 is weak, even if the motor outlet hole 176 is opened, the reverse outer peripheral wind W1 may not be able to draw gas from the motor space 171 through the motor outlet hole 176, and the reverse internal wind W2 may not be generated. If the reverse internal wind W2 is not generated, there is a concern that foreign matter may enter the motor space 171 from the motor outlet hole 176 along with the reverse outer peripheral wind W1.

[0195] In contrast, the duration threshold TDm is set to the time required for the flow of the reverse outer peripheral wind W1 to become strong enough to generate the reverse internal wind W2 after the motor 61 starts to drive. When the drive duration Dm reaches the duration threshold TDm, the inverter control unit 82 determines that the flow of the reverse outer peripheral wind W1 has become strong enough to generate the reverse internal wind W2. When the drive duration Dm reaches the duration threshold TDm, the inverter control unit 82 proceeds to step S104.

[0196] In step S104, inverter control unit 82 performs a valve opening process. In the valve opening process, a process is performed to set drive seal 183 to an open state S2. For example, when drive seal 183 is in a closed state S1, inverter control unit 82 drives seal drive unit 183a to transition drive seal 183 from the closed state S1 to an open state S2. When drive seal 183 is already in the closed state S1, inverter control unit 82 controls seal drive unit 183a to maintain drive seal 183 in the open state S2.

[0197] If the motor 61 is not being driven or if the drive duration Dm has not reached the duration threshold TDm, the inverter control unit 82 proceeds to step S105. In step S105, the inverter control unit 82 performs a valve closing process. In the valve closing process, a process is performed to set the driven seal 183 to the closed state S1. For example, if the driven seal 183 is in the open state S2, the inverter control unit 82 drives the seal drive unit 183a to transition the driven seal 183 from the open state S2 to the closed state S1. If the driven seal 183 is already in the open state S2, the inverter control unit 82 controls the seal drive unit 183a to maintain the driven seal 183 in the closed state S1.

[0198] In this embodiment, when the drive duration Dm reaches the duration threshold TDm, the drive seal 183 opens the motor outlet hole 176. In this configuration, the motor outlet hole 176 is opened when the flow of the reverse outer peripheral wind W1 has become sufficiently strong after the motor 61 starts driving. Therefore, the reverse internal wind W2 is likely to flow out from the motor outlet hole 176 into the duct flow path 123 as the drive seal 183 opens. Therefore, the reverse internal wind W2 can prevent foreign matter from entering the motor space 171 from the motor outlet hole 176 together with the reverse outer peripheral wind W1.

[0199] According to this embodiment, the inverter control unit 82 controls the drive seal 183 via the seal drive unit 183a. With this configuration, the inverter control unit 82 can control heat dissipation from the motor space 171 due to the reverse internal wind W2, regardless of events such as the reverse outer peripheral wind W1 that occurs when the motor 61 is driven. Therefore, the inverter control unit 82 can improve the heat dissipation effect of the motor device 60 by, for example, transitioning the drive seal 183 to the open state S2 when heat dissipation from the motor device 60 is required.

[0200] Sixth Embodiment In the fifth embodiment, the drive seal 183 is opened regardless of the motor rotation speed. In contrast, in the sixth embodiment, the drive seal 183 is opened according to the motor rotation speed. The configurations, actions, and effects of the sixth embodiment that are not specifically described are the same as those of the fifth embodiment. The sixth embodiment will be described mainly focusing on the differences from the fifth embodiment.

[0201] In this embodiment, the EPU control process will be described with reference to the flowchart of Fig. 19. The inverter control unit 82 performs the processes of steps S101 to S105 in the same manner as in the fifth embodiment.

[0202] In step S103, if the drive duration Dm reaches the duration threshold TDm, the inverter control unit 82 proceeds to step S201. In step S201, the inverter control unit 82 determines whether the motor rotation speed Sm has reached the rotation speed threshold TSm. The inverter control unit 82 calculates the motor rotation speed Sm using a detection signal from the motor rotation sensor 233. The rotation speed threshold TSm is a value determined in advance through testing or the like, and is stored in the memory 84 or the like. The rotation speed threshold TSm is set to, for example, 1000 rpm.

[0203] In the propulsion device 15, if the motor rotation speed Sm is insufficient, the flow of the reverse outer peripheral wind W1 is insufficient, making it difficult for the reverse internal wind W2 to be generated. For example, even if the drive duration Dm reaches the duration threshold TDm, if the reverse internal wind W2 is not generated when the motor outlet hole 176 is opened, there is a concern that foreign matter will enter the motor space 171 from the motor outlet hole 176 together with the reverse outer peripheral wind W1.

[0204] In contrast, the rotation speed threshold value TSm is set to a value required for the generation of the reverse internal wind W2 in association with the opening of the motor outlet hole 176. When the motor rotation speed Sm reaches the rotation speed threshold value TSm, the inverter control unit 82 determines that the flow of the reverse outer peripheral wind W1 has become strong enough to generate the reverse internal wind W2. When the motor rotation speed Sm reaches the rotation speed threshold value TSm, the inverter control unit 82 proceeds to step S104 and performs a valve opening process. When the motor rotation speed Sm does not reach the rotation speed threshold value TSm, the inverter control unit 82 proceeds to step S105 and performs a valve closing process.

[0205] In this embodiment, when the motor rotation speed Sm reaches the rotation speed threshold value TSm, the motor outlet hole 176 is opened by the drive seal 183. In this configuration, the motor rotation speed Sm is used as a parameter for determining whether to open the drive seal 183, so the motor outlet hole 176 can be opened when the flow of the reverse outer peripheral wind W1 has reliably become strong. Therefore, the rotation of the motor 61 can be used to reliably prevent foreign matter from entering the motor space 171 through the motor outlet hole 176 together with the reverse outer peripheral wind W1.

[0206] The inverter control unit 82 may determine whether the motor rotation speed Sm has reached the rotation speed threshold value TSm, regardless of the determination result of whether the motor 61 is being driven or whether the drive duration time Dm has reached the duration threshold value TDm. Furthermore, the inverter control unit 82 does not have to determine whether the motor 61 is being driven or whether the drive duration time Dm has reached the duration threshold value TDm.

[0207] <Seventh Embodiment> In the sixth embodiment, the drive seal 183 is opened regardless of the motor temperature. In contrast, in the seventh embodiment, the drive seal 183 is opened in response to the motor temperature. The configurations, actions, and effects of the seventh embodiment that are not specifically described are the same as those of the sixth embodiment. In the sixth embodiment, the differences from the sixth embodiment will be mainly described.

[0208] In this embodiment, the EPU control process will be described with reference to the flowchart of Fig. 20. The inverter control unit 82 performs the processes of steps S101 to S105 and S201 in the same manner as in the sixth embodiment.

[0209] In step S201, if the motor rotation speed Sm reaches the rotation speed threshold value TSm, the inverter control unit 82 proceeds to step S202. In step S202, the inverter control unit 82 determines whether the motor temperature Tm has reached the temperature threshold value TTm. The inverter control unit 82 calculates the motor temperature Tm using the detection signal of the motor temperature sensor 234. The temperature threshold value TTm is a value determined in advance through testing or the like, and is stored in the memory 84 or the like. For example, the temperature threshold value TTm is set to the upper limit of the temperature range in which the motor 61 operates normally.

[0210] If the motor temperature Tm has reached the temperature threshold value TTm, the inverter control unit 82 proceeds to step S104 to perform a valve opening process. If the motor temperature Tm has not reached the temperature threshold value TTm, the inverter control unit 82 proceeds to step S105 to perform a valve closing process.

[0211] According to this embodiment, in the propulsion device 15, the motor space 171 is ventilated by the reverse internal air W2 to prevent the motor temperature Tm from becoming so high that it reaches the temperature threshold TTm. Therefore, if the motor 61 is not at a high temperature, it is not necessary to ventilate the motor space 171 by the reverse internal air W2. For example, if the motor temperature Tm has not reached the temperature threshold TTm, by not opening the motor outlet hole 176, it is possible to prioritize preventing foreign matter from entering the motor space 171 through the motor outlet hole 176 over enhancing the heat dissipation effect of the motor 61. Furthermore, by limiting the opening of the drive seal 183 to when the motor 61 is at a high temperature, it is possible to reduce the frequency with which gas is circulated inside the motor housing 70. This reduces the risk of foreign matter entering the motor housing 70.

[0212] The inverter control unit 82 may determine whether the motor temperature Tm has reached the temperature threshold value TTm regardless of the determination result of whether the motor 61 is being driven or whether the drive duration time Dm has reached the duration threshold value TDm. The inverter control unit 82 may also determine whether the motor temperature Tm has reached the temperature threshold value TTm regardless of the determination result of whether the motor rotation speed Sm has reached the rotation speed threshold value TSm. Furthermore, the inverter control unit 82 does not have to determine whether the motor 61 is being driven or whether the drive duration time Dm has reached the duration threshold value TDm, or whether the motor rotation speed Sm has reached the rotation speed threshold value TSm.

[0213] Eighth Embodiment In the fifth embodiment, the drive seal 183 is opened regardless of the motor internal pressure or the motor external pressure. In contrast, in the eighth embodiment, the drive seal 183 is opened in response to the motor internal pressure or the motor external pressure. The configurations, actions, and effects not specifically described in the eighth embodiment are the same as those in the fifth embodiment. The eighth embodiment will be described mainly focusing on the differences from the fifth embodiment.

[0214] In this embodiment, the EPU control process will be described with reference to the flowchart of Fig. 21. The inverter control unit 82 performs the processes of steps S101, S104, and S105 in the same manner as in the fifth embodiment.

[0215] After step S101, the inverter control unit 82 proceeds to step S301. In step S301, the inverter control unit 82 determines whether the drive seal 183 is in the closed state S1. If the drive seal 183 is in the closed state S1, the inverter control unit 82 proceeds to step S302.

[0216] In step S302, the inverter control unit 82 determines whether the motor internal pressure Pin is equal to or greater than the second internal pressure P2. The inverter control unit 82 calculates the motor internal pressure Pin using the detection signal of the internal pressure sensor 231. The second internal pressure P2 is a predetermined value that is stored in the memory 84 or the like. For example, the second internal pressure P2 is set to the upper limit of the pressure range in which the motor 61 operates normally. The second internal pressure P2 is also set to a value greater than the motor external pressure Pout. The inverter control unit 82 calculates the motor external pressure Pout using the detection signal of the external pressure sensor 232. The second internal pressure P2 may be variably set depending on the motor external pressure Pout.

[0217] In the propulsion device 15, if the motor outflow hole 176 is opened while the motor internal pressure Pin is insufficient, there is a concern that foreign matter, together with the reverse outer peripheral wind W1, may enter the motor space 171 through the motor outflow hole 176. For example, if the motor internal pressure Pin is equal to or lower than the motor external pressure Pout, foreign matter and the reverse outer peripheral wind W1 are likely to enter the motor space 171 through the motor outflow hole 176. In contrast, the second internal pressure P2 is set to a value large enough to prevent foreign matter and the reverse outer peripheral wind W1 from entering the motor space 171 through the motor outflow hole 176 even when the motor outflow hole 176 is opened.

[0218] When the motor internal pressure Pin reaches the second internal pressure P2, the inverter control unit 82 proceeds to step S104 and performs a valve opening process. In this case, the motor internal pressure Pin is large enough to reach the second internal pressure P2. Therefore, even if the motor outlet hole 176 is opened, foreign matter and the reverse outer peripheral wind W1 are unlikely to flow into the motor space 171 through the motor outlet hole 176.

[0219] If the drive seal 183 is not in the closed state S1 or if the motor internal pressure Pin has not reached the second internal pressure P2, the inverter control unit 82 proceeds to step S303. In step S303, the inverter control unit 82 determines whether the drive seal 183 is in the open state S2. If the drive seal 183 is in the open state S2, the inverter control unit 82 proceeds to step S304.

[0220] In step S304, the inverter control unit 82 determines whether the motor internal pressure Pin is equal to or less than the first internal pressure P1. The first internal pressure P1 is a predetermined value stored in the memory 84 or the like. For example, the first internal pressure P1 is set to a value smaller than the second internal pressure P2. The first internal pressure P1 is also set to a value larger than the motor external pressure Pout. The first internal pressure P1 may be variably set depending on the motor external pressure Pout.

[0221] When the motor internal pressure Pin drops to the first internal pressure P1, the inverter control unit 82 proceeds to step S105 and performs a valve closing process. In this case, the motor internal pressure Pin is small enough to drop to the first internal pressure P1. This prevents the seal drive unit 183a from transitioning the drive seal 183 from the open state S2 to the closed state S1 against an excessively large motor internal pressure Pin.

[0222] The operation of the drive seal 183 will be described with reference to FIG. 22. In FIG. 22, the drive seal 183 is illustrated as Valve, the closed state S1 as close, and the open state S2 as open. In FIG. 22, when the drive seal 183 is in the closed state S1, the motor internal pressure Pin is approximately the same value as the motor external pressure Pout at timing t1. The motor internal pressure Pin increases after timing t1 and reaches the first internal pressure P1 at timing t2. However, when the drive seal 183 is in the closed state S1, the drive seal 183 remains in the closed state S1 even if the motor internal pressure Pin reaches the first internal pressure P1.

[0223] The motor internal pressure Pin increases after timing t2 and reaches the second internal pressure P2 at timing t3. At timing t3, the motor internal pressure Pin reaches the second internal pressure P2, causing the drive seal 183 to transition from the closed state S1 to the open state S2. After timing t3, the motor internal pressure Pin decreases overall, and at timing t4, the motor internal pressure Pin decreases to the first internal pressure P1, causing the drive seal 183 to transition from the open state S2 to the closed state S1.

[0224] <Ninth Embodiment> In the first embodiment, the reverse internal wind W2 flows into the motor space 171 via the shaft space 165. In contrast, in the ninth embodiment, the reverse internal wind W2 flows into the motor space 171 without passing through the shaft space 165. The configurations, actions, and effects not specifically described in the ninth embodiment are the same as those in the first embodiment. The ninth embodiment will be described mainly focusing on the differences from the first embodiment.

[0225] As shown in Figures 23 and 24, the motor inlet hole 175 directly connects the inverter housing hole 95 and the motor space 171 to allow ventilation. That is, the inverter housing hole 95 and the motor space 171 are able to communicate with each other without passing through the shaft space 165. The motor inlet hole 175 directly opens the motor space 171 toward the downwind side of the propeller wind Wp without passing through the shaft space 165. The motor inlet hole 175 is provided on the outer peripheral side of the shaft outer wall 161. The motor inlet hole 175 is provided between the shaft outer wall 161 and the inverter inner peripheral wall 92 in the radial direction RD. A plurality of motor inlet holes 175 are arranged in the circumferential direction CD. The motor shaft 65 does not enter the motor inlet hole 175. The motor shaft 65 is covered in the axial direction AD by the second motor opposing wall 73b.

[0226] As shown in FIG. 24 , in the motor space 171, the reverse internal air W2 can pass through the holder extension portion 142 and the shaft flange 162 in the axial direction AD. The holder extension portion 142 is provided with a holder ventilation hole 145. The holder ventilation hole 145 penetrates the holder extension portion 142 in the axial direction AD. A plurality of the holder ventilation holes 145 are arranged in the circumferential direction CD. The shaft flange 162 is provided with a flange ventilation hole 163. The flange ventilation hole 163 penetrates the shaft flange 162 in the axial direction AD. The flange ventilation holes 163 are arranged in the circumferential direction CD. The holder ventilation hole 145 and the flange ventilation hole 163 are arranged in the axial direction AD.

[0227] Tenth Embodiment In the first embodiment, the backflow fan 110 is provided between the motor device 60 and the propeller 20. In contrast, in the tenth embodiment, the backflow fan 110 is provided on the opposite side of the motor device 60 from the propeller 20. Configurations, actions, and effects not specifically described in the tenth embodiment are the same as those in the first embodiment. The tenth embodiment will be described mainly focusing on the differences from the first embodiment.

[0228] As shown in Figure 25, the reverse flow fan 110 is located on the opposite side of the propeller 20 with respect to both the motor device 60 and the inverter device 80. The motor shaft 65 passes through the inverter housing hole 95 and spans between the reverse flow fan 110 and the motor rotor 64. The motor shaft 65 extends further toward the second duct opening 122 than the inverter housing 90. Unlike the first embodiment, the air filter 185 is attached to the motor shaft 65. The air filter 185 is fixed to the shaft outer wall 161 so as to cover the shaft inlet hole 166 from the second duct opening 122 side. The air filter 185 is fixed to the shaft end wall 161b with an adhesive or the like.

[0229] Eleventh Embodiment In the first embodiment, the plurality of inverter devices 80 each have an individual inverter housing 90. In contrast, in the eleventh embodiment, the plurality of inverter devices 80 share a common inverter housing. Configurations, actions, and effects that are not specifically described in the eleventh embodiment are the same as those in the first embodiment. The eleventh embodiment will be described mainly focusing on the differences from the first embodiment.

[0230] As shown in Figure 26, the EPU 50 has a common housing 90A. The common housing 90A is a housing in which multiple inverter housings 90 are integrated. Each of the multiple inverter devices 80 includes a portion of the common housing 90A. In each of the multiple inverter devices 80, the inverter section 86 is housed in the common housing 90A. The common housing 90A has an inverter housing hole 95 formed therein, similar to the inverter housing 90 of the first embodiment.

[0231] <Twelfth Embodiment> In the first embodiment, the motor device 60 is provided between the inverter device 80 and the propeller 20 in the axial direction AD. In contrast, in the twelfth embodiment, the inverter device 80 is provided between the motor device 60 and the propeller 20 in the axial direction AD. Configurations, actions, and effects that are not particularly described in the twelfth embodiment are the same as those in the first embodiment. The twelfth embodiment will be described mainly focusing on the differences from the first embodiment.

[0232] 27 , the two inverter devices 80 are arranged side by side in the axial direction AD via the motor device 60. That is, the motor device 60 is provided between two inverter devices 80 adjacent to each other in the axial direction AD. In the inverter device 80 provided between the motor device 60 and the propeller 20, the motor shaft 65 extends in the axial direction AD so as to span between the motor rotor 64 and the backflow fan 110, and is inserted into the inverter housing hole 95.

[0233] <Thirteenth Embodiment> In the first embodiment, the motor device 60 is provided between the plurality of inverter devices 80 and the propeller 20 in the axial direction AD. In contrast, in the thirteenth embodiment, the plurality of inverter devices 80 are provided between the motor device 60 and the propeller 20 in the axial direction AD. Configurations, actions, and effects that are not particularly described in the thirteenth embodiment are the same as those in the first embodiment. The thirteenth embodiment will be described mainly focusing on the differences from the first embodiment.

[0234] 28 , the motor device 60 is provided on the opposite side of the propeller 20 in the axial direction AD via the plurality of inverter devices 80. In the plurality of inverter devices 80, the motor shaft 65 is inserted through the inverter housing hole 95. As in the tenth embodiment, the air filter 185 is fixed to the motor shaft 65 so as to cover the shaft inlet hole 166 from the second duct opening 122 side.

[0235] <Fourteenth Embodiment> In the first embodiment, the motor outlet hole 176 serving as the housing outlet hole is provided in the motor housing 70. In contrast, in the fourteenth embodiment, the housing outlet hole is provided in the inverter housing 90. The configurations, actions, and effects of the fourteenth embodiment that are not specifically described are the same as those of the first embodiment. The fourteenth embodiment will be described mainly focusing on the differences from the first embodiment.

[0236] As shown in Figure 29, the inverter housing 90 has an inverter space 241. The inverter space 241 is the internal space of the inverter housing 90. The inverter unit 86 is accommodated in the inverter space 241. The inverter unit 86 corresponds to the propulsion drive unit. The inverter housing 90 corresponds to the drive housing. The inverter space 241 corresponds to the housing space. The inverter outer surface 96 corresponds to the housing outer surface. The inverter inner surface 97 corresponds to the housing inner surface.

[0237] The inverter housing 90 has an inverter inlet hole 245 and an inverter outlet hole 246. The inverter inlet hole 245 is a hole for allowing gas to flow into the inverter space 241. For example, the reverse internal wind W2 flows into the inverter space 241 through the inverter inlet hole 245. The inverter inlet hole 245 penetrates the inverter outer wall 94 to open the inverter space 241 to the outside of the inverter housing 90. The inverter inlet hole 245 corresponds to a housing inlet hole.

[0238] The inverter inlet hole 245 opens the inverter space 241 toward the inverter housing hole 95. The inverter space 241 connects the inverter space 241 and the internal space of the inverter housing hole 95 in a manner that allows air to pass through. The inverter inlet hole 245 is provided in the inverter inner circumferential wall 92. The inverter inlet hole 245 penetrates the inverter inner circumferential wall 92 in the radial direction RD. A plurality of the inverter inlet holes 245 are arranged in the circumferential direction CD. A plurality of the inverter inlet holes 245 may also be arranged in the axial direction AD.

[0239] The inverter outflow hole 246 is a hole for allowing gas to flow from the inverter space 241 to the outside of the inverter housing 90. For example, the reverse internal wind W2 flows out from the inverter space 241 through the inverter outflow hole 246. The inverter outflow hole 246 penetrates the inverter outer wall 94 so as to open the inverter space 241 to the outside of the inverter housing 90. The inverter outflow hole 246 opens the inverter space 241 toward the duct flow path 123. The inverter outflow hole 246 connects the inverter space 241 and the duct flow path 123 in a manner that allows ventilation. The inverter outflow hole 246 corresponds to a housing outflow hole.

[0240] The inverter outlet hole 246 is provided in the inverter outer peripheral wall 91. The inverter outlet hole 246 penetrates the inverter outer peripheral wall 91 in the radial direction RD. The inverter outlet hole 246 is in a state of bridging between the inverter outer peripheral outer surface 96a and the inverter outer peripheral inner surface 97a in the inverter outer peripheral wall 91. A plurality of the inverter outlet holes 246 are arranged in the circumferential direction CD. A plurality of the inverter outlet holes 246 may also be arranged in the axial direction AD.

[0241] The inverter device 80 has an inverter seal 247. The inverter seal 247 is provided in the inverter housing 90 in a state in which it can open and close the inverter outflow hole 246. The inverter seal 247 is formed of a valve member, an opening / closing member, a lip seal, or the like. An inverter seal 247 is provided individually for each of the multiple inverter outflow holes 246. Similar to the inverter outflow holes 246, multiple inverter seals 247 are arranged in the circumferential direction CD.

[0242] Like the motor seal 181, the inverter seal 247 can be transitioned between a closed state S1 and an open state S2. With the inverter seal 247, the closed state S1 corresponds to the restricting state, and the open state S2 corresponds to the permitting state. The inverter seal 247 corresponds to the outflow restricting portion. The inverter seal 247 is formed from a resin material, a rubber material, or the like so as to be elastically deformable. The inverter seal 247 has an air-blocking property that blocks airflow. Like the motor seal 181, the inverter seal 247 transitions between the closed state S1 and the open state S2 by elastic deformation. The inverter seal 247 corresponds to the elastic restricting portion.

[0243] In this embodiment, the EPU 50 has the same number of motor devices 60 and inverter devices 80. For example, one EPU 50 has one motor device 60 and one inverter device 80.

[0244] <Fifteenth Embodiment> In the first embodiment, a plurality of inverter devices 80 are arranged in the axial direction AD in the EPU 50. In contrast, in the fifteenth embodiment, a plurality of inverter devices 80 are arranged in the circumferential direction CD in the EPU 50. Configurations, actions, and effects that are not specifically described in the fifteenth embodiment are the same as those in the first embodiment. The fifteenth embodiment will be described mainly with respect to differences from the first embodiment.

[0245] As shown in FIG. 30 , in one EPU 50, a plurality of inverter devices 80 are arranged in the circumferential direction CD. Each of the plurality of inverter devices 80 is located adjacent to the motor device 60 in the axial direction AD. In the EPU 50, a plurality of inverter housings 90 are arranged in the circumferential direction CD. In a configuration in which the EPU 50 has two inverter devices 80, two semi-annular inverter housings 90 are arranged in the circumferential direction CD. In the EPU 50, an inverter housing hole 95 is formed by combining a plurality of inverter housings 90. In the EPU 50, a plurality of inverter units 86 are arranged in the circumferential direction CD. Note that a plurality of inverter devices 80 may also be arranged in the radial direction RD.

[0246] <Sixteenth Embodiment> In the first embodiment, the backflow fan 110 is provided between the motor device 60 and the propeller 20 in the axial direction AD. In contrast, in the sixteenth embodiment, the backflow fan 110 is provided on the opposite side of the motor device 60 from the propeller 20. The configurations, actions, and effects of the sixteenth embodiment that are not specifically described are the same as those of the first embodiment. The sixteenth embodiment will be described mainly with reference to the differences from the first embodiment.

[0247] 31 , the backflow fan 110 is provided between the motor device 60 and the inverter device 80 in the axial direction AD. The motor shaft 65 protrudes in the axial direction AD beyond the motor housing 70 toward the inverter housing 90. The backflow fan 110 is provided on the protruding portion of the motor shaft 65. The backflow fan 110 may also be provided between two inverter devices 80 adjacent to each other in the axial direction AD. Furthermore, in a configuration in which the EPU 50 has a plurality of motor devices 60, the backflow fan 110 may also be provided between two motor devices 60 adjacent to each other in the axial direction AD.

[0248] <Seventeenth Embodiment> In the first embodiment, the propulsion device 15 is provided with a counterflow fan 110 that causes gas to flow in the opposite direction to the propeller wind Wp in the axial direction AD as a blower fan. In contrast, in the seventeenth embodiment, the propulsion device 15 is provided with a blower fan that causes gas to flow in the same direction as the propeller wind Wp in the axial direction AD. The configurations, actions, and effects not specifically described in the sixteenth embodiment are the same as those in the second embodiment. The sixteenth embodiment will be described mainly focusing on the differences from the second embodiment.

[0249] As shown in FIG. 32 , the EPU 50 has a forward flow fan 115. The forward flow fan 115 blows gas in the same direction as the propeller wind Wp in the axial direction AD. The forward flow fan 115 has substantially the same configuration as the counterflow fan 110 of the first embodiment, except that the blowing direction of the forward flow fan 115 is the same as the propeller wind Wp. For example, like the counterflow fan 110 of the first embodiment, the forward flow fan 115 is mounted on the motor shaft 65 so as to rotate together with the motor shaft 65. The forward flow fan 115 has forward flow blades 116. The forward flow blades 116 have substantially the same configuration as the counterflow blades 111 of the first embodiment, except that the blowing direction of the forward flow fan 115 is the same as the propeller wind Wp. For example, the forward flow blades 116 extend radially outward from the motor shaft 65.

[0250] The forward flow fan 115 blows air to generate a forward peripheral wind W3 and a forward internal wind W4. The forward flow fan 115 corresponds to a blower fan. In the forward flow fan 115, the rotation direction of the forward flow fan 115 and the orientation of the forward flow blades 116 are set so that the forward peripheral wind W3 flows in the same direction as the propeller wind Wp in the axial direction AD. For example, in the forward flow fan 115, the rotation direction of the forward flow fan 115 is the same as the rotation direction of the propeller 20, and the orientation of the forward flow blades 116 is the same as the orientation of the propeller blades 21. In the forward flow blades 116, the tilt direction of the forward flow blades 116 in the circumferential direction CD with respect to the motor axis Cm is the same as the tilt direction of the propeller blades 21 in the circumferential direction CD with respect to the motor axis Cm. In addition, in the downstream blades 116, the rotation direction of the downstream fan 115 may be opposite to the rotation direction of the propeller 20, and the orientation of the downstream blades 116 may be opposite to the orientation of the propeller blades 21.

[0251] <Other Embodiments> The disclosure of this specification is not limited to the exemplified embodiments. The disclosure encompasses the exemplified embodiments and modifications thereto by those skilled in the art. For example, the disclosure is not limited to the combinations of parts and elements shown in the embodiments, and can be implemented in various modifications. The disclosure can be implemented in various combinations. The disclosure can have additional parts that can be added to the embodiments. The disclosure encompasses the omission of parts and elements from the embodiments. The disclosure encompasses the substitution or combination of parts and elements between one embodiment and another embodiment. The disclosed technical scope is not limited to the description of the embodiments. The disclosed technical scope is defined by the claims, and should be interpreted as including all modifications within the meaning and scope equivalent to the claims.

[0252] In each of the above embodiments, housing outlet holes such as the motor outlet hole 176 may be provided in any manner in a drive housing such as the motor housing 70. For example, in the above first embodiment, the motor outlet hole 176 may be provided in the first motor-facing wall 73a or the like as long as gas such as the reverse internal wind W2 can flow from the motor space 171 to the duct flow path 123. Furthermore, the motor outlet hole 176 may be provided in a position aligned with the motor fins 79 in the circumferential direction CD.

[0253] In each of the above embodiments, housing inlet holes such as the motor inlet hole 175 may be provided in any manner in the drive housing. For example, in the first embodiment, the motor inlet hole 175 may be provided in the motor outer peripheral wall 71 or the first motor facing wall 73a as long as gas such as the reverse internal wind W2 can flow into the motor space 171. Furthermore, the housing inlet hole does not have to be provided in the drive housing. In this case, it is preferable that the housing outlet hole have an open area and number that allow gas to flow in as well as out.

[0254] In each of the above embodiments, the outflow restriction portion, such as the motor seal 181, may have any configuration as long as it can open and close the housing outflow hole. For example, in the first embodiment, the motor seal 181 may be formed in a plate shape using a material that is not easily elastically deformed. For example, the motor seal 181 is pivotally supported on the motor housing 70 so that it can open and close. The motor seal 181 is provided with a biasing member, such as a spring, that biases the motor seal 181 toward the closed state S1. When the reverse outer peripheral wind W1 occurs, the reverse outer peripheral wind W1 and the reverse internal wind W2 open the motor seal 181 against the biasing force of the biasing member, causing the motor seal 181 to transition from the closed state S1 to the open state S2.

[0255] In each of the above embodiments, the foreign object control portion, such as the air filter 185, may have any configuration as long as it can prevent foreign objects from entering the housing inlet hole. For example, in the first embodiment, a centrifugal separator or a labyrinth structure portion may be provided for the housing inlet hole as the foreign object control portion. The centrifugal separator is a device that uses centrifugal force to separate foreign objects from the reverse internal wind W2 flowing into the housing inlet hole. The labyrinth structure portion is a structure that has a long, labyrinth-shaped space and removes foreign objects from the reverse internal wind W2 as the reverse internal wind W2 passes through the long, labyrinth-shaped space.

[0256] In each of the above embodiments, the motor 61 does not have to be a double-rotor motor. For example, the motor 61 may be a single-rotor motor. Furthermore, the motor 61 does not have to be an axial gap motor. For example, the motor 61 may be a radial gap motor. In a radial gap motor, the rotor and stator are aligned in the radial direction RD.

[0257] In each of the above embodiments, the propulsion control device may include at least one of the flight control device 40 and the inverter control unit 82. Furthermore, at least one of the flight control device 40 and the inverter control unit 82 may execute EPU control processing.

[0258] In each of the above embodiments, one propulsion device 15 may have multiple EPUs 50. For example, one propulsion device 15 may have multiple EPUs 50 arranged in the radial direction RD or the circumferential direction CD. The EPUs 50 may be provided at positions offset from the propellers 20 in the radial direction RD.

[0259] In each of the above embodiments, the vertical take-off and landing aircraft on which the propulsion device 15 is mounted may be an electrically powered vertical take-off and landing aircraft in which at least one propeller 20 is driven by at least one EPU 50. For example, a configuration in which one propeller 20 is driven by multiple EPUs 50, or a configuration in which one EPU 50 drives multiple propellers 20, may also be used.

[0260] In each of the above embodiments, the air vehicle on which the propulsion device 15 is mounted does not have to be a vertical take-off and landing aircraft as long as it is electrically powered. For example, the air vehicle may be an electric aircraft capable of take-off and landing with a taxiing motion. Furthermore, the air vehicle may be a rotary-wing aircraft or a fixed-wing aircraft. The air vehicle may also be an unmanned air vehicle with no crew on board. The unmanned air vehicle may or may not have a crew cabin 14. Furthermore, a pilot may remotely operate the air vehicle. The eVTOL 10 may be referred to as a manned air vehicle as long as it is capable of carrying a person.

[0261] In each of the above embodiments, the moving body on which the propulsion device 15 is mounted does not have to be an aircraft, as long as it can move by rotation of a rotating body. For example, the moving body may be a vehicle, a ship, construction machinery, or agricultural machinery. For example, if the moving body is a vehicle or construction machinery, the rotating body may be a wheel for movement, and the output shaft may be an axle. If the moving body is a ship, the rotating body may be a screw propeller for propulsion, and the output shaft may be a propeller shaft.

[0262] In each of the above embodiments, the flight control device 40 and the inverter control unit 82 are provided by a control system including at least one computer. The control system includes at least one processor that is hardware. If this processor is referred to as a hardware processor, the hardware processor can be provided by the following (i), (ii), or (iii):

[0263] (i) A hardware processor may be a hardware logic circuit. In this case, the computer is provided by a digital circuit including a large number of programmed logic units (gate circuits). The digital circuit may include a memory that stores at least one of a program and data. The computer may be provided by an analog circuit. The computer may be provided by a combination of a digital circuit and an analog circuit.

[0264] (ii) The hardware processor may be at least one processor core that executes a program stored in at least one memory. In this case, a computer is provided by at least one memory and at least one processor core. The processor core is referred to as a CPU, for example. The memory is also referred to as a storage medium. The memory is a non-transitory, tangible storage medium that non-temporarily stores "at least one of a program and data" that can be read by the processor.

[0265] (iii) The hardware processor may be a combination of (i) above and (ii) above, where (i) and (ii) are located on different chips or on a common chip.

[0266] That is, at least one of the means and functions provided by the flight control device 40 and the inverter control unit 82 can be provided by hardware only, software only, or a combination thereof.

[0267] (Disclosure of Technical Ideas) This specification discloses multiple technical ideas described in the following multiple clauses. Some clauses may be described in a multiple dependent form, with the subsequent clause alternatively referring to the preceding clause. Furthermore, some clauses may be described in a multiple dependent form, with the subsequent clause referring to another multiple dependent clause. These multiple dependent clauses define multiple technical ideas.

[0268] (Technical Idea 1) A propulsion device (15) for propelling a moving body (10), comprising: a propulsion drive unit (61, 86) driven by electricity to propel the moving body; and a drive housing (70, 90) that houses the propulsion drive unit, wherein the drive housing has: a housing inner surface (77, 97) that forms a housing space (171, 241) that houses the propulsion drive unit; a housing outer surface (76, 96) that is provided outside the housing inner surface and extends along an outer flow path (78, 123, 210) formed outside the housing inner surface; and a housing outflow hole (176, 246) that connects the outer flow path to the housing space so that gas in the housing space flows out to the outer flow path.

[0269] (Technical Idea 2) The drive housing has a housing inlet hole (175, 245) that opens the housing space to the outside of the drive housing so that gas can flow into the housing space from the outside of the drive housing. This is a propulsion device described in Technical Idea 1.

[0270] (Technical Idea 3) The propulsion device according to Technical Idea 2, further comprising a foreign object control section (185) that allows gas to flow into the housing inlet hole while restricting foreign objects from entering the housing space through the housing inlet hole.

[0271] (Technical Idea 4) The drive housing has a housing outer peripheral wall (71) extending in the axial direction (AD) and covering the propulsion drive unit from the outer periphery, and a housing cover wall (73b) covering the propulsion drive unit from the axial direction, wherein the housing outlet hole is provided in the housing outer peripheral wall, and the housing inlet hole is provided in the housing cover wall, a propulsion device according to Technical Idea 2 or 3.

[0272] (Technical Idea 5) A propulsion device according to any one of Technical Ideas 2 to 4, comprising a cover member (200) that covers the housing inlet hole from the axial direction so as to allow gas to flow into the housing inlet hole and to guide foreign matter away from the housing inlet hole toward the outer periphery, thereby restricting the foreign matter from entering the housing inlet hole.

[0273] (Technical Idea 6) A propulsion device according to any one of Technical Ideas 2 to 5, wherein the propulsion drive unit has a drive shaft (65) that rotates in response to the drive of the propulsion drive unit, and the drive shaft has a shaft inlet hole (166) that opens the internal space to the outside of the drive shaft so that gas flowing into the housing inlet hole flows into the internal space (165) of the drive shaft, and a shaft outlet hole (167) that connects the internal space with the housing space so that gas in the internal space flows out into the housing space.

[0274] (Technical Idea 7) A propulsion device that propels the moving body by rotation of a propeller (20), the propulsion device described in any one of Technical Ideas 2 to 6, wherein the housing inlet hole opens the housing space toward the downwind side of a propeller wind (Wp) generated by the rotation of the propeller.

[0275] (Technical Idea 8) A propulsion device according to any one of Technical Ideas 1 to 7, comprising an outflow restriction section (181, 183, 247) provided for the housing outflow hole and capable of transitioning between a restriction state (S1) that restricts the outflow of gas from the housing outflow hole and an allowance state (S2) that allows the outflow of gas from the housing outflow hole.

[0276] (Technical Idea 9) A propulsion device according to Technical Idea 8, comprising an elastic restriction section (181, 247) as the outflow restriction section, which transitions from the restricted state to the permitted state by elastic deformation due to the flow of gas in the outer flow path, and transitions from the permitted state to the restricted state by a restoring force against the flow of gas in the outer flow path.

[0277] (Technical Idea 10) A propulsion device according to Technical Idea 8 or 9, comprising, as the outflow restriction unit, a control restriction unit (183) that controls the transition between the restricted state and the permitted state, a restriction drive unit (183a) that drives to transition the state of the control restriction unit, and a drive control unit (82) that controls the drive of the restriction drive unit.

[0278] (Technical Idea 11) The propulsion device according to any one of Technical Ideas 1 to 10, further comprising a blower fan (64, 110, 115) that blows air so that the gas flows from the housing space through the housing outlet hole and into the outer flow path.

[0279] (Technical Idea 12) A propulsion device according to any one of Technical Ideas 1 to 11, wherein the propulsion drive unit has a motor (61) including a motor rotor (64) that rotates around a rotation axis (Cm), and the motor rotor has rotor blades (144) that blow air so that gas flows out of the housing outlet hole into the outer flow path as the motor rotor rotates.

[0280] (Technical Idea 13) A propulsion device according to any one of Technical Ideas 1 to 12, comprising an outer duct (120) covering the housing outer surface and the housing outlet hole from the outside so as to form the outer flow path between the housing outer surface and the outer duct.

[0281] (Technical Concept 14) A propulsion device according to any one of Technical Concepts 1 to 13, which is provided in an aircraft (10) that is the moving body, and is a propulsion device that drives the aircraft to propel it.

[0282] (Technical Concept 15) The propulsion device according to Technical Concept 14, wherein the flying vehicle has a crew compartment (14).

[0283] (Technical Idea 16) A propulsion device (15) is provided in an aircraft (10) having a crew cabin (14) and propels the aircraft, the propulsion device (15) comprising: a motor (61) driven by electricity to propel the aircraft; and a drive housing (70) accommodating the motor, the drive housing comprising: a housing inner surface (77) forming a housing space (171) accommodating the motor; and an outer flow path (78, ) provided outside the housing inner surface and formed outside the housing inner surface.the motor comprises: a housing outer surface (76) extending along a rotation axis (Cm) (123); a housing outer peripheral wall (71) extending in an axial direction (AD) and covering the motor from the outer peripheral side; a housing covering wall (73b) covering the motor from the axial direction; a housing outflow hole (176) provided in the housing outer peripheral wall and connecting the outer flow path and the housing space so that gas in the housing space flows out to the outer flow path; and a housing inflow hole (175) provided in the housing covering wall and opening the housing space to the outside of the drive housing so that gas flows from the outside of the drive housing into the housing space, the motor comprising: a motor rotor (64) rotating about a rotation axis (Cm); and a drive shaft (65) rotating as the motor is driven, the drive shaft comprising: a shaft inflow hole (166) opening the internal space (165) of the drive shaft to the outside of the drive shaft so that gas flowing into the housing inflow hole flows into the internal space of the drive shaft, a shaft outlet hole (167) connecting the internal space and the housing space so that gas in the internal space flows out into the housing space, the motor rotor having rotor blades (144) that blow air so that gas flows out of the housing outlet hole into the outer flow path as the motor rotor rotates, and further having a foreign matter control section (185) that controls foreign matter from entering the housing space through the housing inlet hole while allowing gas to flow into the housing inlet hole, an outflow control section (181) that is provided for the housing outflow hole and is capable of switching between a controlled state (S1) that controls the outflow of gas from the housing outflow hole and an allowed state (S2) that allows the outflow of gas from the housing outflow hole, and an elastic control section (181) as the outflow control section that changes from the controlled state to the allowed state by elastic deformation due to the flow of gas in the outer flow path, and changes from the allowed state to the controlled state by a restoring force that resists the flow of gas in the outer flow path, A blower fan (64, 110,and an outer duct (120) covering the housing outer surface and the housing outlet hole from the outside so as to form the outer flow path between the housing outer surface and the outer duct.

Claims

1. A propulsion device (15) for propelling a moving body (10), comprising: a propulsion drive unit (61, 86) driven by electricity to propel the moving body; and a drive housing (70, 90) that accommodates the propulsion drive unit, wherein the drive housing has: a housing inner surface (77, 97) that forms a housing space (171, 241) that accommodates the propulsion drive unit; a housing outer surface (76, 96) that is provided on the outside of the housing inner surface and extends along an outer flow path (78, 123, 210) formed on the outside of the housing inner surface; and a housing outflow hole (176, 246) that connects the outer flow path and the housing space so that gas in the housing space flows out to the outer flow path.

2. The propulsion device according to claim 1, wherein the drive housing has a housing inlet hole (175, 245) that opens the housing space to the outside of the drive housing so that gas can flow into the housing space from the outside of the drive housing.

3. A propulsion device as described in claim 2, further comprising a foreign object control section (185) that allows gas to flow into the housing inlet hole while controlling the ingress of foreign objects into the housing space through the housing inlet hole.

4. A propulsion device as described in claim 2 or 3, wherein the drive housing has a housing outer peripheral wall (71) extending in the axial direction (AD) and covering the propulsion drive unit from the outer circumferential side, and a housing cover wall (73b) covering the propulsion drive unit from the axial direction, the housing outflow hole being provided in the housing outer peripheral wall, and the housing inflow hole being provided in the housing cover wall.

5. A propulsion device as described in claim 2 or 3, further comprising a cover member (200) covering the housing inlet hole from the axial direction so as to allow gas to flow into the housing inlet hole and to guide foreign matter away from the housing inlet hole toward the outer periphery, thereby preventing the foreign matter from entering the housing inlet hole.

6. A propulsion device as described in claim 2 or 3, wherein the propulsion drive unit has a drive shaft (65) that rotates in association with the drive of the propulsion drive unit, and the drive shaft has: a shaft inlet hole (166) that opens the internal space to the outside of the drive shaft so that gas flowing into the housing inlet hole flows into the internal space (165) of the drive shaft; and a shaft outlet hole (167) that connects the internal space to the housing space so that gas in the internal space flows out into the housing space.

7. A propulsion device that propels the moving body by rotating a propeller (20), wherein the housing inlet hole opens the housing space toward the downwind side of the propeller wind (Wp) generated by the rotation of the propeller, as described in claim 2 or 3.

8. A propulsion device as described in claim 1, further comprising an outflow restriction section (181, 183, 247) provided for the housing outflow hole and capable of transitioning between a restriction state (S1) in which the outflow of gas from the housing outflow hole is restricted and an allowance state (S2) in which the outflow of gas from the housing outflow hole is permitted.

9. A propulsion device as described in claim 8, comprising an elastic restriction section (181, 247) as the outflow restriction section, which transitions from the restricted state to the permitted state by elastic deformation due to the flow of gas in the outer flow passage, and which transitions from the permitted state to the restricted state by a restoring force against the flow of gas in the outer flow passage.

10. A propulsion device as described in claim 8 or 9, comprising, as the outflow restriction unit, a control restriction unit (183) which controls the transition between the restricted state and the permitted state, a restriction drive unit (183a) which drives to transition the state of the control restriction unit, and a drive control unit (82) which controls the drive of the restriction drive unit.

11. A propulsion device as claimed in claim 1 or 2, further comprising a blower fan (64, 110, 115) for blowing gas from said housing space through said housing outlet hole to flow out to said outer flow passage.

12. A propulsion device as described in claim 1 or 2, wherein the propulsion drive section has a motor (61) including a motor rotor (64) rotating around a rotation axis (Cm), and the motor rotor has rotor blades (144) that blow air so that gas flows out of the housing outlet hole into the outer flow path as the motor rotor rotates.

13. A propulsion device as claimed in claim 1 or 2, further comprising an outer duct (120) covering the housing outer surface and the housing outlet hole from the outside so as to form the outer flow passage between the housing outer surface and the outer duct.

14. A propulsion device as described in claim 1 or 2, which is provided on an aircraft (10) that is the moving body, and is a propulsion device that drives the aircraft to propel the aircraft.

15. The propulsion system of claim 14, wherein the air vehicle has a passenger compartment (14).

16. A propulsion device (15) for propelling an aircraft (10) having a passenger compartment (14), comprising: a motor (61) driven by electricity to propel the aircraft; and a drive housing (70) accommodating the motor. The drive housing comprises a housing inner surface (77) forming a housing space (171) accommodating the motor; and an outer flow passage (78,the motor has a housing outer surface (76) extending along a rotation axis (123), a housing outer peripheral wall (71) extending in an axial direction (AD) and covering the motor from the outer peripheral side, a housing covering wall (73b) covering the motor from the axial direction, a housing outflow hole (176) provided in the housing outer peripheral wall connecting the outer flow path and the housing space such that gas in the housing space flows out to the outer flow path, and a housing inflow hole (175) provided in the housing covering wall opening the housing space to the outside of the drive housing such that gas flows from the outside of the drive housing into the housing space, the motor has a motor rotor (64) rotating about a rotation axis (Cm), and a drive shaft (65) rotating with the motor being driven, the drive shaft having a shaft inflow hole (166) opening the internal space to the outside of the drive shaft such that gas flowing into the housing inflow hole flows into the internal space (165) of the drive shaft, and a shaft outlet hole (167) connecting the internal space and the housing space so that gas in the internal space flows out into the housing space, the motor rotor having rotor blades (144) for blowing air so that gas flows out of the housing outlet hole into the outer flow path as the motor rotor rotates, and further comprising: a foreign matter control section (185) for controlling foreign matter from entering the housing space through the housing inlet hole while allowing gas to flow into the housing inlet hole; an outflow control section (181) provided for the housing outflow hole and capable of transitioning between a restricted state (S1) for controlling the outflow of gas from the housing outflow hole and an allowed state (S2) for allowing gas to flow out of the housing outflow hole; and an elastic control section (181) as the outflow control section, which elastically deforms due to the flow of gas in the outer flow path to transition from the restricted state to the allowed state, and which transitions from the allowed state to the restricted state due to a restoring force against the flow of gas in the outer flow path; A blower fan (64, 110,and an outer duct (120) covering the housing outer surface and the housing outlet hole from the outside so as to form the outer flow passage between the housing outer surface and the outer duct.

Images