Electric engine, electric propulsion device and aircraft

Abstract

The embodiments of the present application provide an electric engine, an electric propulsion device and an aircraft, and relate to the field of aircraft technology. The drive motor of the electric engine is connected to the power motor, the radiator has an air duct, and the radiator is connected to the power motor, the fan is connected to the drive motor by transmission, the drive motor drives the fan to rotate, and along the axial direction of the fan, the guide structure has an air inlet side and an air outlet side, the drive motor and the power motor are located on the air inlet side of the guide structure, the fan and the radiator are located on the air outlet side of the guide structure, the fan is located between the guide structure and the radiator, and the guide structure at least guides part of the airflow on the air inlet side to the middle area of ​​the fan. The electric engine provided by the present application can reduce the heat reflux formed between the fan and the radiator due to the flow velocity difference of the airflow, reduce or eliminate the reverse heating of the drive motor and the power motor by the heat reflux, make the airflow distribution and speed blown to the radiator more uniform, and ensure the normal operation of the power motor.

Description

Technical Field

[0001] The present application relates to the field of aircraft technology, and in particular to an electric engine, an electric propulsion device and an aircraft. Background Art

[0002] An electric vertical take-off and landing (eVTOL) aircraft includes an electric propulsion device, which includes a propeller and an electric engine. The electric engine includes a motor, which is connected to the propeller and is used to drive the propeller to rotate. The motor is a high-power, heat-generating motion device. If the temperature of the motor cannot be controlled within a reasonable range, the output performance of the motor will decrease.

[0003] At present, many high-power heat-generating moving devices, such as the drive motors of new energy vehicles and the engines of fuel vehicles, generate a lot of heat during operation, so they are usually equipped with a cooling system consisting of a radiator and a fan. The airflow generated by the fan blows through the radiator, thereby taking away the heat generated by the moving devices. However, the heat dissipation of drive motors and engines such as automobiles is relatively spacious due to the structural layout and no rigid quality requirements. Therefore, in order to meet the heat dissipation requirements, there will not be too many restrictions on the size of the radiator and the fan, and usually the front end of the radiator will not be very tight and have too much obstruction. Therefore, the heat dissipation efficiency can be improved by increasing the volume of the radiator and the fan or increasing the distance between the radiator and the fan.

[0004] However, in order to meet the requirements of weight and layout space, electric vertical take-off and landing aircraft usually require the design of products to be small and exquisite, and to ensure the achievement of performance. It can be seen that electric engines are usually designed to be small in size, so the space for arranging radiators and fans in electric engines is small, so it is impossible to arrange large-volume radiators and fans in related fields, and it is impossible to increase the distance between the radiator and the fan, and thus it is impossible to meet the heat dissipation needs of the motor. In addition, the overall compactness of the entire electric engine is relatively high, and the air inlet end of the radiator may be blocked by structures such as the motor and pump. This type of layout will inevitably cause new problems that do not occur in other industries, such as uneven distribution of the air intake, which will seriously cause a large amount of heat reflux in the middle area of ​​the radiator.

[0005] Therefore, how to ensure heat dissipation while designing the electric engine to be small in size becomes a problem that needs to be solved urgently. Summary of the invention

[0006] The present application aims to provide an electric engine, an electric propulsion device and an aircraft, which achieve good heat dissipation effect on the power motor and meet the requirement of a small integrated volume of the electric engine.

[0007] A first aspect of an embodiment of the present application provides an electric engine, comprising:

[0008] Power motor;

[0009] Drive motor;

[0010] A radiator, the radiator having air ducts and used for dissipating heat from the power motor;

[0011] A fan, the fan is drivingly connected to the driving motor, and the driving motor is used to drive the fan to rotate;

[0012] A flow guide structure, wherein along the axial direction of the fan, the flow guide structure has an air inlet side and an air outlet side, and the drive motor and the power motor are both located on the air inlet side of the flow guide structure;

[0013] The fan and the radiator are both located on the air outlet side of the air guide structure, and the fan is located between the air guide structure and the radiator;

[0014] The flow guiding structure is used to guide at least part of the airflow on the air inlet side to the middle area of ​​the fan.

[0015] The electric engine provided in the embodiment of the present application, without increasing the volume of the radiator or fan to improve the heat dissipation effect, in the process of the driving motor driving the fan to dissipate heat to the radiator, the guide structure will guide the airflow from the air inlet side to the air outlet side and further to the fan, the fan dissipates heat to the radiator, and the radiator dissipates heat to the power motor, wherein the guide structure will guide a part of the airflow to flow to the middle area of ​​the fan, and when the flow area of ​​the middle area does not change, the air intake volume of the middle area is increased to increase the flow rate of the airflow in the middle area of ​​the fan, thereby reducing the flow rate difference between the airflow passing through the middle area of ​​the fan and the rest of the positions on the fan, so that the flow rate distribution of the airflow passing through each area on the fan is more uniform, thereby improving the uniformity of the airflow distribution, and further reducing the heat reflux formed between the fan and the radiator due to the flow rate difference of the airflow, and reducing or eliminating the reverse heating of the drive motor and the power motor by the heat reflux.

[0016] In addition, through the guiding effect of the guide structure, the airflow in the middle of the fan can dissipate heat to the middle area of ​​the radiator, and finally the airflow distribution and speed blowing onto the radiator are more uniform, which has a significant effect on improving the heat dissipation efficiency of the radiator. In this way, the radiator can dissipate heat for the power motor well and ensure the normal operation of the power motor.

[0017] In one possible implementation, the guide structure includes a first guide path and a second guide path, the first guide path is used to guide the airflow on the air inlet side to the fan along a vertical direction, and the second guide path is used to guide part of the airflow on the air inlet side from the outside of the guide structure to the inside of the guide structure, and from the inside to the middle area of ​​the fan.

[0018] In a possible implementation, the guide structure includes a plurality of guide fins, one ends of the plurality of guide fins are connected, and the other ends of the plurality of guide fins are arranged at intervals along the circumference of the fan;

[0019] Each of the guide fins is arranged to be inclined relative to the central axis of the fan, so that the first guide path and the second guide path are formed between the guide fins.

[0020] In a possible implementation, an angle between the guide fin and the central axis of the fan is greater than or equal to 5° and less than or equal to 15°.

[0021] In one possible implementation, the fan includes blades, and along the radial direction of the fan, a horizontal distance between an outer edge of the blades and an outer side wall of the radiator is L1, and a horizontal distance between an outer edge of the guide fins and the outer side wall of the radiator is L2, where L1≥L2.

[0022] In a possible implementation, the fan includes:

[0023] A wheel hub, the wheel hub being drivingly connected to the drive motor;

[0024] A plurality of fan blades, the plurality of fan blades are arranged at intervals along the circumference of the hub and connected to the hub;

[0025] At least one group of airflow channels is formed on the hub, and the airflow channels are used to guide at least part of the airflow directed to the middle area of ​​the fan to the heat sink.

[0026] In a possible implementation, the number of the airflow channels is two groups, the two groups of airflow channels are respectively a first group of airflow channels and a second group of airflow channels, and the first group of airflow channels and the second group of airflow channels are spaced apart and distributed along the radial direction of the hub;

[0027] And the first group of air flow channels is close to the center of the hub.

[0028] In a possible implementation, the first group of airflow channels includes a plurality of circular through holes, and the plurality of circular through holes are distributed around the hub at intervals along the circumference.

[0029] In a possible implementation, the second group of airflow channels includes a plurality of special-shaped through holes, and the plurality of special-shaped through holes are distributed around the circumference of the hub at intervals.

[0030] In one possible implementation,

[0031] The flow guide structure is fixedly connected to the housing of the power motor;

[0032] Alternatively, it further comprises a fan cover, the air guide structure is fixedly connected to the fan cover, and the fan cover is fixedly connected to the radiator or the housing of the power motor.

[0033] In a possible implementation, the power motor has a liquid cooling channel;

[0034] The outlet end of the liquid cooling channel is connected to the inlet end of the radiator, and the outlet end of the radiator is connected to the inlet end of the liquid cooling channel. The liquid cooling channel and the radiator form a cooling medium circulation loop.

[0035] In a possible implementation, the electric engine further includes a liquid supply pipe and a liquid return pipe;

[0036] The outlet end of the liquid cooling channel is connected to the inlet end of the radiator through the liquid return pipe, and the outlet end of the radiator is connected to the inlet end of the liquid cooling channel through the liquid supply pipe. The liquid cooling channel, the liquid return pipe, the radiator and the liquid supply pipe form the circulation loop.

[0037] In a possible implementation, the liquid supply pipe and the liquid return pipe are both rigid pipes, and the radiator is rigidly connected to the power motor via the liquid supply pipe and the liquid return pipe.

[0038] In a possible implementation, the electric engine further includes a liquid pump, which is disposed on the power motor and located on the circulation loop and is used to drive the flow of cooling medium on the circulation loop.

[0039] In a possible implementation, the first output end of the drive motor is drivingly connected to the fan, and the second output end of the drive motor is drivingly connected to the liquid pump. The drive motor is used to drive the fan to rotate and enable the liquid pump to drive the cooling medium to flow.

[0040] A second aspect of an embodiment of the present application provides an electric propulsion device, which includes a propeller and an electric engine as described above;

[0041] The propeller is drivingly connected to the power motor of the electric engine, and the power motor is used to drive the propeller to rotate.

[0042] In a possible implementation, the method further includes:

[0043] Fairing;

[0044] The propeller has a blade, and the blade includes a blade root portion. The blade root portion is located outside the fairing, and the blade root portion cooperates with the fairing.

[0045] In a possible implementation, the paddle root is a plate-shaped structure.

[0046] In a possible implementation, an angle between a width extension direction of the blade root and a central axis of the fairing is less than 55°.

[0047] In one possible implementation, a plurality of flow paths are formed between the blades and the wind inlet side of the guide structure of the electric motor, and the flow paths are used to transfer the airflow generated by the blades to the wind inlet side of the guide structure through the power motor.

[0048] In a possible implementation, the power motor includes a stator and a rotor, an air gap is formed between the rotor and the stator, and a first flow path is formed between the blade and the wind inlet side of the guide structure of the electric engine through the air gap;

[0049] And / or, a rotor through hole is provided on the rotor, and a second flow path is formed between the blade and the air inlet side of the guide structure of the electric engine through the rotor through the rotor through hole;

[0050] And / or, a third flow path is formed between the blade and the wind inlet side of the guide structure of the electric engine on the outer peripheral side of the power motor.

[0051] A third aspect of an embodiment of the present application provides an aircraft, comprising the electric propulsion device described above and a fuselage, wings and a tail, wherein the electric propulsion device is arranged on the wings and / or the fuselage and / or the tail. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0053] Figure 1 A schematic diagram of the structure of an aircraft provided in an embodiment of the present application;

[0054] Figure 2A schematic diagram of the structure of an electric propulsion device provided in an embodiment of the present application;

[0055] Figure 3 A schematic diagram of the structure of an electric engine provided in an embodiment of the present application;

[0056] Figure 4 A simplified structural diagram of an electric engine provided in an embodiment of the present application;

[0057] Figure 5 A schematic diagram of airflow at an electric engine provided in an embodiment of the present application;

[0058] Figure 6 A schematic diagram of a flow guide structure and airflow on a fan provided in an embodiment of the present application;

[0059] Figure 7 A schematic diagram of a flow guide structure and airflow on a fan provided in an embodiment of the present application;

[0060] Figure 8 A schematic diagram of the positional relationship between a guide fin and a central axis of a fan provided in an embodiment of the present application;

[0061] Fig. 9 A schematic diagram of the structure of a fan provided in an embodiment of the present application;

[0062] Fig.10 A schematic diagram of the structure of a propeller from a first perspective provided in an embodiment of the present application;

[0063] Fig.11 A structural schematic diagram of a propeller from a second perspective provided in an embodiment of the present application;

[0064] Fig.12 A schematic structural diagram of a propeller from a third perspective provided in an embodiment of the present application;

[0065] Fig.13 A simulation diagram of the air flow velocity at various positions of an electric engine when it is working is provided in an embodiment of the present application.

[0066] Description of reference numerals:

[0067] 10-aircraft; 20-electric propulsion device;

[0068] 11-fuselage; 12-wing; 13-tail; 14-arm; 15-nacelle;

[0069] 21-propeller; 21a-blade; 22-electric engine; 23-fairing; 24-propeller root;

[0070] 25-Freedom Department;

[0071] 100-power motor;

[0072] 110-stator; 120-rotor; 130-air gap; 140-rotor through hole; 150-rear cover;

[0073] 200-driving motor;

[0074] 300- Radiator;

[0075] 310-liquid supply pipe; 320-liquid return pipe; 330-liquid pump;

[0076] 400-Fan;

[0077] 410-fan blade; 420-wheel hub;

[0078] 421-air flow channel; 421a-first group of air flow channels; 421b-second group of air flow channels;

[0079] 422-circular through hole; 423-special-shaped through hole;

[0080] 500- diversion structure;

[0081] 510 - air inlet side; 520 - air outlet side; 530 - first flow guiding path; 540 - second flow guiding path;

[0082] 550-guide fins. DETAILED DESCRIPTION

[0083] As described in the background technology, when an aircraft is in operation, the motor will generate a large amount of heat. In the related technology, a radiator is used to dissipate the heat from the motor. For example, the heat generated by the motor flows into the radiator, and then the heat of the radiator is taken away by the flow of external air, thereby forming a cooling effect. However, when the radiator uses external air flow to dissipate heat, the heat dissipation efficiency is low.

[0084] For this reason, a fan is often set to blow air to the radiator to achieve the purpose of dissipating heat from the radiator. Among them, when the fan and the radiator are arranged, the fan is arranged above the radiator, and the fan blows air downward to dissipate the heat from the radiator. In the related field, in order to improve the heat dissipation effect, the volume of the radiator or the fan is increased or the distance between the radiator and the fan is increased to achieve the effect of improving the heat dissipation. However, the increase in the volume of the radiator or the fan and the increase in the distance between the radiator and the fan often lead to an increase in the volume of the equipment, but the electric engine of the aircraft is small in size, and the space for arranging the heat dissipation system is often small. It is impossible to arrange a large-volume radiator or fan in the related field, and it is impossible to increase the distance between the radiator and the fan.

[0085] It is understandable that many high-power heat-generating moving devices, such as the drive motors of new energy vehicles and the engines of fuel vehicles, generate a lot of heat during operation, so they are usually equipped with a cooling system (radiator and fan). The airflow generated by the fan blows through the radiator, thereby taking away the heat generated by the moving devices. For motors and engines such as automobiles, the heat dissipation is relatively spacious because of the structural layout and no rigid quality requirements. Therefore, in order to meet the heat dissipation requirements, there will not be too many restrictions on the size of the radiator and the size of the fan, and usually the front end of the radiator will not be very tight and too much shielding. In order to meet the requirements of weight and layout space, the current electric vertical take-off and landing aircraft usually requires the design of products to be small and precise, and to ensure the achievement of performance. In this way, the air inlet of the radiator will be blocked by the motor and pump. This layout will inevitably cause new problems that do not occur in other industries, such as uneven distribution of the air inlet, which will seriously cause a large amount of heat reflux in the middle area of ​​the radiator.

[0086] Therefore, in an electric vertical take-off and landing aircraft, due to space and weight requirements, the volume of the radiator and the fan cannot be increased, and the distance between the power motor and the fan cannot be increased, resulting in poor heat dissipation performance of the radiator.

[0087] The inventors of the embodiments of the present application have analyzed and found that during the heat dissipation process, heat reflux will occur between the fan and the radiator, and the heat reflux will reversely heat the electric propulsion device arranged above the fan, which may easily cause the temperature rise of the electric propulsion device to increase and affect the normal operation, thereby reducing the reliability of the electric propulsion device. For high-power motors in aircraft, the heat generated by the motors will be greater, the temperature of the heat reflux will be higher, and the effect of the heat reflux on the heat dissipation of the motors will be more significant, thereby further affecting the heat dissipation of the electric propulsion device.

[0088] The reason for this problem is that the motor in the electric propulsion device (such as the power motor) and the drive motor that drives the fan are both located on the side of the fan facing away from the radiator. In the axial direction of the fan, the drive motor and the power motor are located in the middle area of ​​the fan. Therefore, the drive motor and the power motor will hinder the air intake in the middle area of ​​the fan, resulting in a decrease in the air intake volume in the middle area of ​​the fan and a decrease in the airflow velocity in the middle area of ​​the fan, resulting in less airflow from the fan to the middle area of ​​the radiator, uneven airflow distribution on the radiator, and affected heat dissipation effect of the radiator.

[0089] Furthermore, in the related art, the distance between the radiator and the fan is increased so that the distance between the radiator and the fan is larger. Under the action of turbulence and diffusion effects, the airflow generated in the middle and edge of the fan will gradually mix during the propagation process as the distance from the fan increases. The flow rate difference between the airflow generated in the middle and edge of the fan will decrease, and heat reflux will not occur.

[0090] In order to ensure the small size of the electric engine, the present application cannot increase the distance between the radiator and the fan, resulting in a closer distance between the fan and the radiator. In the airflow blowing to the radiator, the flow rate difference between the airflow in the middle of the fan and the airflow at the edge of the fan is more obvious, and the flow rate difference cannot be reduced by airflow mixing, which will cause heat reflux between the fan and the radiator.

[0091] In addition, due to the centrifugal force of the fan's rotation, the wind speed of the outer ring of the fan is higher than that of the inner ring. In addition, the radiator structure will block the smooth passage of airflow. This will eventually cause the air between the fan and the radiator to be squeezed outward, forming a bottom-up (reverse) heat reflux phenomenon, which will reversely heat the power motor, drive motor and other components above the fan, making it impossible for the power motor and drive motor to dissipate heat in time, affecting the operation of the power motor and drive motor.

[0092] In view of the above technical problems, the embodiments of the present application provide an electric engine, an electric propulsion device and an aircraft. Without increasing the volume of the radiator or fan to improve the heat dissipation effect, during the process of the fan dissipating heat to the radiator, the guide structure will guide the airflow from the air inlet side to the air outlet side and further to the fan, the fan dissipates heat to the radiator, and the radiator dissipates heat to the power motor, wherein the guide structure will guide a part of the airflow to the middle area of ​​the fan, and when the flow area of ​​the middle area does not change, the air intake volume of the middle area is increased to increase the flow rate of the airflow in the middle area of ​​the fan, thereby reducing the size of the middle area of ​​the fan and the fan. The difference in flow velocity of the airflow passing through other positions on the fan makes the flow velocity distribution of the airflow passing through various areas on the fan more uniform, thereby improving the uniformity of airflow distribution, and further reducing the heat reflux caused by the flow velocity difference of the airflow between the fan and the radiator, reducing or eliminating the reverse heating of the drive motor and the power motor by the heat reflux. In addition, through the guiding effect of the guide structure, the airflow in the middle of the fan can dissipate the heat to the middle area of ​​the radiator, and finally the airflow distribution and speed blown onto the radiator are more uniform, which has a significant effect on improving the heat dissipation efficiency of the radiator. In this way, the radiator can dissipate the heat of the power motor well and ensure the normal operation of the power motor.

[0093] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0094] refer to Figure 1The embodiment of the present application also provides an aircraft 10, which may include an electric propulsion device 20, a fuselage 11, and wings 12 fixedly connected to the fuselage 11. The fuselage 11 may be a symmetrical structure. The structure of the fuselage 11 may refer to the fuselage structure of an existing aircraft, and the structure of the wing 12 may also refer to the fixed wing structure of an existing aircraft, which will not be repeated here.

[0095] The electric propulsion device 20 may be arranged on the fuselage 11 or may be arranged on the fuselage 11. Figure 1 As shown, the electric propulsion device 20 is disposed on the wing 12 , or in some examples, the electric propulsion device 20 may be disposed on both the fuselage 11 and the wing 12 .

[0096] Among them, Figure 1 As shown, when the electric propulsion device 20 is arranged on the wing 12, the electric propulsion device 20 can be connected to the wing 12 through the arm 14, for example, one end of the arm 14 is connected to the wing 12, and the other end of the arm 14 is connected to the electric propulsion device 20. Of course, in some examples, the electric propulsion device 20 can also be connected to the wing 12 through other connecting mechanisms. It is understood that the number of electric propulsion devices 20 arranged on the wing 12 includes but is not limited to Figure 1 The 6 shown may also be 4 or 8, etc. In some examples, the number of electric propulsion devices 20 provided on the wing 12 may be adjusted according to demand.

[0097] In some examples, such as Figure 1 As shown, a tail wing 13 is disposed at the rear of the fuselage 11. The tail wing 13 is symmetrically disposed relative to the fuselage 11. An electric propulsion device 20 may also be disposed on the tail wing 13. Figure 1 As shown, an electric propulsion device 20 is provided on each tail wing 13 .

[0098] In the present application examples, see Figure 1 As shown, the aircraft 10 further includes a nacelle 15, which is disposed on the tail 13, and the electric propulsion device 20 is connected to the nacelle 15, so that the electric propulsion device 20 is disposed on the tail 13 through the nacelle 15. In some examples, the electric propulsion device 20 on the tail 13 can also be connected to the tail 13 through the arm 14.

[0099] In the present application examples, see Figure 1As shown, in different flight phases and working conditions, when each electric propulsion device 20 is in operation, the two electric propulsion devices 20 located on the tail 13 have different positional relationships with the extension direction of the fuselage 11 when the axial direction rotates. In one example, the four electric propulsion devices 20 located on the outside of the wing 12 (i.e., away from the fuselage 11) can be perpendicular to or intersect with the extension direction of the fuselage 11 when the axial direction rotates. Among them, the two electric propulsion devices 20 located on the tail 13 can be tilt-rotors, the four electric propulsion devices 20 located on the outside of the wing 12 (i.e., away from the fuselage 11) can be fixed rotors, and the two electric propulsion devices 20 located on the inside of the wing 12 (close to the fuselage 11) can also be tilt-rotors.

[0100] The specific structure of the electric propulsion device 20 is described in detail below.

[0101] In the present application embodiment, Figure 2 As shown, the electric propulsion device 20 may include a propeller 21 and an electric motor 22. The propeller 21 is in transmission connection with the electric motor 22, and the electric motor 22 can drive the propeller 21 to rotate.

[0102] The electric propulsion device 20 provided in the present application uses an electric engine 22 to drive the upper propeller 21 to rotate. The propeller 21 can generate a downward airflow during the rotation process. The downward airflow can blow toward the electric engine 22. The airflow takes away a large amount of heat generated by the electric engine 22 during operation through air cooling, thereby achieving air cooling of the electric engine 22, improving the heat dissipation effect of the electric engine 22, reducing the possibility of overheating of the electric engine 22, and improving the working reliability of the electric propulsion device 20.

[0103] In some embodiments, the electric propulsion device 20 may include a power battery, an electric motor 22, a propeller 21, and accessory structures.

[0104] refer to Figure 2 ,as well as Figures 3 to 5 In some embodiments, the electric propulsion device 20 may further include a fairing 23 .

[0105] The propeller 21 has a plurality of blades 21a, which can be arranged at intervals along the circumference of the electric motor 22. The blades 21a may include a blade root 24 and a free portion 25, both of which are located outside the fairing 23, and the propeller 21 may also include a blade shaft and a hub.

[0106] The propeller hub can be arranged in the fairing 23, and one end of the propeller shaft is connected to the propeller hub, the other end of the propeller shaft passes through the fairing 23 and is connected to the propeller root 24 outside the fairing 23, the other end of the propeller root 24 is connected to the free part 25, and the propeller root 24 is located between the free part 25 and the propeller hub.

[0107] In some embodiments, the propeller shaft can drive the propeller root 24 to rotate around the axial direction of the propeller shaft to adjust the angle between the width extension direction of the propeller root 24 and the central axis of the fairing 23. There can be a gap between the propeller root 24 and the fairing 23, so that when the propeller shaft drives the propeller root 24 and the free portion 25 to rotate around the axial direction of the propeller shaft, it is avoided that the propeller root 24 contacts with the fairing 23 during the rotation process and hinders the rotation of the propeller root 24.

[0108] In some embodiments, the propeller root 24, the free portion 25 and the propeller shaft may be an integral structure. The propeller shaft is fixedly connected to the propeller hub.

[0109] The blade root 24 may be a plate-like structure. Figure 5 The flat structure is shown. The fairing 23 can be connected to the electric motor 22.

[0110] In this way, by setting the part of the propeller root 24 located outside the fairing 23 to a plate-like structure, compared with the approximately cylindrical structure in the related technology, the contact area between the propeller root 24 of the plate-like structure and the air is larger along the rotation direction of the blade 21a, and a large amount of airflow can be generated, thereby providing more airflow to the electric motor 22, facilitating air cooling of the electric motor 22, and improving the heat dissipation effect of the electric motor 22.

[0111] refer to Figure 5 In some embodiments, the angle between the width extension direction of the blade root 24 and the central axis of the fairing 23 (such as Figure 5 For example, the included angle between the width extension direction of the blade root 24 and the central axis of the fairing 23 may be one of 20°, 30°, 40° and 50°.

[0112] In this way, it is possible to avoid reducing the contact area between the propeller root 24 and the air due to too small an angle, thereby avoiding reducing the airflow generated by the propeller root 24 due to too small a contact area between the propeller root 24 and the air, thereby ensuring that the propeller 21 generates a large amount of airflow when rotating.

[0113] refer to Figure 7 In some embodiments, a plurality of flow paths (such as Figure 7 As shown in the flow paths a1, a2 and a3 in the figure, the flow paths are used to flow the airflow generated by the blades 21a through the power motor 100 to the air inlet side 510 of the guide structure 500.

[0114] In this way, by setting up multiple flow paths, the large amount of airflow generated when the blades 21a rotate can flow more toward the power motor 100 of the electric engine 22, so as to facilitate air cooling and heat dissipation of the power motor 100 through the airflow on the multiple flow paths.

[0115] Furthermore, by setting up multiple flow paths, the flow rate of the airflow generated when the blade 21a rotates through the power motor 100 to the flow guide structure 500 can be increased, and the obstruction of the power motor 100 to the airflow flowing to the fan 400 can be reduced, thereby further increasing the flow rate of the airflow flowing to the fan 400, improving the heat dissipation effect of the fan 400 on the radiator 300, and improving the reliability of the electric engine 22 and the electric propulsion device 20.

[0116] refer to Figure 7 In some embodiments, the power motor 100 may include a stator 110 and a rotor 120, an air gap 130 is formed between the rotor 120 and the stator 110, and a first flow path (such as Figure 7 ) as shown in the flow path a1.

[0117] In this way, since the air gap 130 forms the first flow path located between the rotor 120 and the stator 110 of the power motor 100, a part of the airflow generated when the propeller 21 rotates passes through the power motor 100. In this way, the blocking effect of the power motor 100 on the airflow can be reduced, making it easier for more airflow to flow to the fan 400 and the guide structure 500, which helps to improve the heat dissipation effect of the radiator 300.

[0118] In addition, the airflow generated when the propeller 21 rotates can take away part of the heat on the power motor 100 when passing through the first flow path, which helps to dissipate the heat of the power motor 100, thereby improving the heat dissipation effect of the electric motor 22.

[0119] The rotor 120 is provided with a rotor through hole 140, and a second flow path (such as Figure 7 The air gap 130 is closer to the center area of ​​the power motor 100 than the rotor through hole 140.

[0120] In this way, the second flow path formed by the rotor through hole 140 can facilitate the airflow generated by the rotation of the propeller 21 to pass through the power motor 100, which can further reduce the blocking effect of the power motor 100 on the airflow and further increase the airflow flowing to the fan 400 and the guide structure 500.

[0121] A third flow path (eg, Figure 7 The third flow path enables the airflow generated when the propeller 21 rotates to flow from the outer peripheral side of the power motor 100 to the fan 400 and the guide structure 500, thereby increasing the amount of airflow flowing to the fan 400 and the guide structure 500.

[0122] The specific structure of the electric motor 22 is described in detail below.

[0123] In order to dissipate the heat generated during the operation of the electric engine 22 in a timely manner, refer to Figure 6 , Figure 7 and Figure 8 An embodiment of the present application provides an electric engine 22 , which may include a power motor 100 , a drive motor 200 , a radiator 300 , a fan 400 and a guide structure 500 .

[0124] In some embodiments, the electric motor 22 may also include a motor controller, cables, etc. and accessories thereof. The electric motor 22 may convert electrical energy into mechanical energy. In actual implementation, the electric motor 22 may also be referred to as an electric propulsion system.

[0125] The power motor 100 can be used to provide power to the propeller 21 of the electric propulsion device 20 to drive the propeller 21 to rotate. The power motor 100 generates a large amount of heat during operation, and the heat generated by the power motor 100 during operation needs to be taken away by the radiator 300. The power motor 100 may include a rear cover 150 for protecting the power motor 100.

[0126] The drive motor 200 can be connected to the shell of the power motor 100, and the drive motor 200 can be connected to the fan 400 in transmission. The fan 400 is arranged on the side of the drive motor 200 facing away from the power motor 100. The drive motor 200 can drive the fan 400 to rotate through the transmission shaft, so that the fan 400 can drive the air to flow toward the bottom of the fan 400 and form an airflow to take away the heat from the power motor 100.

[0127] The radiator 300 can be used to dissipate heat from the power motor 100 . The radiator 300 can be connected to the power motor 100 for heat transfer. The heat generated by the power motor 100 during operation can be transferred to the radiator 300 to dissipate heat for the power motor 100 through the radiator 300 .

[0128] In some embodiments, the heat sink 300 can be located on a side of the fan 400 that faces away from the drive motor 200. For example, the heat sink 300 can be located on a side of the fan 400 that faces away from the drive motor 200. Figure 8Below the middle fan 400, the fan 400 drives the surrounding air to flow downward, so that the airflow passes through the air channels on the radiator 300. In this way, the airflow formed when the fan 400 is working will take away the heat absorbed by the radiator 300, so that the radiator 300 can be cooled by air through the fan 400, and the heat dissipation of the radiator 300 can be accelerated to improve the heat dissipation effect.

[0129] Along the axial direction of the fan 400 (eg Figure 8 In the Y direction), the guide structure 500 has an air inlet side 510 and an air outlet side 520, the drive motor 200 and the power motor 100 are both located on the air inlet side 510 of the guide structure 500, the fan 400 and the radiator 300 are both located on the air outlet side 520 of the guide structure 500, and the fan 400 is located between the guide structure 500 and the radiator 300, and the guide structure 500 is used to guide at least part of the airflow on the air inlet side 510 to the middle area of ​​the fan 400.

[0130] In the process of the fan 400 cooling the radiator 300, the airflow is guided from the air inlet side 510 to the air outlet side 520 and further to the fan 400 through the guide structure 500, the fan 400 cools the radiator 300, and the radiator 300 cools the power motor 100, wherein the guide structure 500 guides a part of the airflow to the middle area of ​​the fan 400, and when the flow area of ​​the middle area does not change, the air inlet volume of the middle area is increased to increase the air flow of the fan 400. The flow rate of the air flow can be reduced, thereby reducing the difference in flow rate between the middle area of ​​the fan 400 and the rest of the positions on the fan 400, making the flow rate distribution of the air flow passing through various areas on the fan 400 more uniform, thereby improving the uniformity of the air flow distribution, and further reducing the heat reflux formed between the fan 400 and the radiator 300 due to the flow rate difference of the air flow, reducing or eliminating the reverse heating of the drive motor 200 and the power motor 100 by the heat reflux, and improving the reliability of the electric engine 22 and the electric propulsion device 20.

[0131] In addition, through the guiding effect of the guide structure 500, the airflow in the middle of the fan 400 can dissipate heat to the middle area of ​​the radiator 300, and the airflow distribution and speed finally blown onto the radiator 300 are more uniform, which has a significant effect on improving the heat dissipation efficiency of the radiator 300. In this way, the radiator 300 can dissipate heat for the power motor 100 well and ensure the normal operation of the power motor 100.

[0132] On the basis of the above embodiment, the fairing 23 and the propeller 21 are fixedly connected to the electric engine 22, and the propeller 21 is transmission-connected to the electric engine 22. The radiator 300, the fan 400 and the guide structure 500 are arranged below the power motor 100, which can enhance the integrated modularity of the electric propulsion device 20 and facilitate the optimized layout of the space.

[0133] refer to Fig. 9 and Fig.10 In some embodiments, the guide structure 500 may include a first guide path 530 and a second guide path 540. The first guide path 530 is used to guide the airflow on the air inlet side 510 to the fan 400 along a vertical direction, and the second guide path 540 is used to guide part of the airflow on the air inlet side 510 from the outside of the guide structure 500 to the inside of the guide structure 500, and then guide it from the inside to the middle area of ​​the fan 400.

[0134] In this way, part of the airflow located on the outside of the guide structure 500 is guided to the inside of the guide structure 500 through the second guide path 540 of the guide structure 500, and then guided to the middle area of ​​the fan 400 from the inside of the guide structure 500, thereby achieving the goal of guiding part of the airflow to the middle area of ​​the fan 400 through the guide structure 500 to increase the airflow volume in the middle area of ​​the fan 400.

[0135] When the flow area on the fan 400 remains unchanged, the airflow volume in the middle area of ​​the fan 400 increases, resulting in an increase in the airflow velocity in the middle area of ​​the fan 400, thereby reducing the air velocity difference between the middle area of ​​the fan 400 and other areas (for example, the area near the edge of the fan 400), reducing the heat reflux phenomenon caused by the flow velocity difference between the fan 400 and the radiator 300, and improving the heat dissipation effect and working reliability of the electric motor 22.

[0136] refer to Fig. 9 In some embodiments, the guide structure 500 may include a plurality of guide fins 550, one ends of the plurality of guide fins 550 are connected, and the other ends of the plurality of guide fins 550 are arranged at intervals along the circumference of the fan 400. The number of the guide fins 550 may be 3, 6, 9, 15, 20 or even more.

[0137] Each guide fin 550 is disposed obliquely relative to the central axis of the fan 400 , so that a first guide path 530 and a second guide path 540 are formed between each guide fin 550 .

[0138] One end of the guide fin 550 facing away from the central axis of the fan 400 is closer to the driving motor 200 than the other end close to the central axis of the fan 400, so that the guide fin 550 is arranged to be tilted downward.

[0139] One end of the second guide path 540 is close to the outside of the guide structure 500, and the other end is close to the inside of the guide structure 500. When the airflow flows into the guide structure 500 from the air inlet side 510, under the guidance of the second guide path 540, the airflow will flow obliquely downward along the second guide path 540 from the outside of the guide structure 500 to the inside of the guide structure 500, and further flow through the inside of the guide structure 500 to the middle area of ​​the fan 400 located below the guide structure 500, so as to provide airflow to the middle area of ​​the fan 400.

[0140] In this way, by making the end of the guide fin 550 facing away from the central axis closer to the drive motor 200 than the end close to the central axis, the inclined guide fin 550 can guide part of the airflow to the central area of ​​the guide structure 500, and further guide the airflow from the central area of ​​the guide structure 500 to the middle area of ​​the fan 400, so as to facilitate the flow rate of the airflow in the central area of ​​the fan 400, reduce the flow rate difference between the airflow in the middle area and other areas of the fan 400, reduce the heat reflux formed between the fan 400 and the radiator 300 due to the flow rate difference of the airflow, make the airflow distribution on the fan 400 more uniform, and reduce or eliminate the reverse heating of the drive motor 200 and the power motor 100 caused by the heat reflux.

[0141] refer to Fig.11 In some embodiments, the angle between the guide fin 550 and the central axis of the fan 400 (eg Fig.11 The angle α in the middle is greater than or equal to 5° and less than or equal to 15°. For example, the angle between the guide fin 550 and the central axis of the fan 400 can be one of 5°, 7°, 9°, 11°, 12°, 13° and 14°. Or the angle between the guide fin 550 and the central axis of the fan 400 can be any angle within the range of greater than or equal to 5° and less than or equal to 15°.

[0142] In this way, it is possible to avoid the problem that the angle between the guide fin 550 and the central axis of the fan 400 is too small, which affects the guiding effect of the second guide path 540 of the guide structure 500 on the airflow, thereby failing to improve the problem that the airflow velocity in the middle area of ​​the fan 400 is too low and the airflow velocity in the edge area of ​​the fan 400 is too high.

[0143] It can also avoid the situation where the angle between the guide fin 550 and the central axis of the fan 400 is too large, which causes the airflow to be guided too much to the middle area of ​​the fan 400 under the guidance of the guide structure 500, thereby causing the airflow velocity in the middle area of ​​the fan 400 to be too high, while the airflow velocity in the edge area is too low, thereby causing the airflow velocity difference between the middle area and the edge area of ​​the fan 400 to increase.

[0144] refer to Figure 8In some embodiments, the fan 400 may include a fan blade 410, and along the radial direction of the fan 400, the horizontal distance between the outer edge of the fan blade 410 and the outer side wall of the radiator 300 is L1, and the horizontal distance between the outer edge of the guide fin 550 and the outer side wall of the radiator 300 is L2, and L1≥L2.

[0145] In this way, the guide fins 550 can completely cover the fan blades 410 in the axial direction of the fan 400, so that the guide structure 500 has a larger guide area relative to the fan blades 410, and the guide structure 500 can guide more airflow to be completely guided to the fan 400, thereby increasing the amount of airflow blown by the fan 400 to the radiator 300, improving the guiding effect of the guide structure 500 on the airflow, and improving the heat dissipation effect of the radiator 300.

[0146] refer to Fig.10 and Fig.12 In some embodiments, the fan 400 includes a hub 420 and a plurality of blades 410. The hub 420 is drivingly connected to the drive motor 200, and the plurality of blades 410 are arranged at intervals along the circumference of the hub 420 and connected to the hub 420. The hub 420 is provided with at least one set of airflow channels 421, and the airflow channels 421 are used to guide at least part of the airflow directed to the middle area of ​​the fan 400 to the heat sink 300.

[0147] Among them, one group of air flow channels 421 , two groups of air flow channels 421 , three groups of air flow channels 421 or even more groups of air flow channels 421 may be arranged on the wheel hub 420 .

[0148] In this way, by setting at least one group of airflow channels 421 on the hub 420 of the fan 400, a part of the airflow flowing to the middle area of ​​the fan 400 can be guided to the radiator 300 through the airflow channel 421, so that the flow rate of the airflow in the middle area of ​​the fan 400 can be increased, thereby increasing the heat dissipation effect of the part of the radiator 300 corresponding to the middle area of ​​the fan 400, improving the heat dissipation effect of the fan 400 on the radiator 300, and further improving the heat dissipation effect of the electric motor 22.

[0149] refer to Fig.10 and Fig.12 In some embodiments, the number of the airflow channels 421 is two groups, the two groups of airflow channels 421 are respectively a first group of airflow channels 421a and a second group of airflow channels 421b, the first group of airflow channels 421a and the second group of airflow channels 421b are distributed at intervals along the radial direction of the hub 420, and the first group of airflow channels 421a is close to the center of the hub 420.

[0150] In this way, by arranging the first group of airflow channels 421a and the second group of airflow channels 421b which are spaced apart along the radial direction of the hub 420, it is possible to increase the flow area of ​​the airflow on the hub 420 while ensuring the structural strength of the hub 420, thereby increasing the flow rate of the airflow on the hub 420 and the airflow volume in the middle area of ​​the fan 400, further reducing the flow rate difference between the airflow in the middle area and other areas of the fan 400, and improving the heat dissipation in the middle area of ​​the radiator 300, thereby improving the heat dissipation effect of the radiator 300.

[0151] refer to Fig.12 In some embodiments, the first group of air flow channels 421 a may include a plurality of circular through holes 422 , and the plurality of circular through holes 422 are spaced apart along the circumference of the hub 420 .

[0152] In this way, the first group of air flow channels 421a includes a plurality of circular through holes 422. The circular through holes can be easily processed, thereby simplifying the processing technology of the hub 420 and improving the production efficiency of the fan 400.

[0153] refer to Fig.12 In some embodiments, the second group of air flow channels 421 b may include a plurality of special-shaped through holes 423 , and the plurality of special-shaped through holes 423 are distributed around the circumference of the hub 420 at intervals.

[0154] In this way, the second group of airflow channels 421b can increase the flow area of ​​the second group of airflow channels 421b by including multiple special-shaped through holes 423. The special-shaped through holes 423 can also easily adapt to the shape of the hub 420, so as to open through holes to a greater extent, thereby increasing the flow area of ​​the special-shaped through holes 423 and increasing the flow rate of the airflow on the hub 420.

[0155] refer to Figure 6 and Figure 8 In some embodiments, the air guide structure 500 is fixedly connected to the fan cover, or the air guide structure 500 can be fixedly connected to the housing of the power motor 100. The fan 400 can also include a fan cover, which is arranged around the outer periphery of the plurality of fan blades 410, and the fan cover can be fixedly connected to the radiator 300, or the fan cover can be fixedly connected to the housing of the power motor 100.

[0156] In this way, by providing a fan cover, the fan 400 can be protected, the influence of external debris on the rotation of the fan 400 can be reduced, and the working reliability of the electric motor 22 can be improved.

[0157] In some embodiments, the guide fins 550 are directly fixed to the fan cover, or the guide fins 550 are integrally formed with the fan cover, or the guide fins 550 are fixedly connected to the housing of the power motor 100 .

[0158] refer to Figure 6 and Figure 8 In some embodiments, the power motor 100 has a liquid cooling channel, the outlet end of the liquid cooling channel is connected to the inlet end of the radiator 300, and the outlet end of the radiator 300 is connected to the inlet end of the liquid cooling channel, and the liquid cooling channel and the radiator 300 form a cooling medium circulation loop.

[0159] In this way, the radiator 300 forms a cooling medium circulation loop with the liquid cooling channel in the power motor 100. The heat generated by the power motor 100 during operation will be absorbed by the cooling medium in the liquid cooling channel, and the heat will be transported to the radiator 300 through the flow of the cooling medium. The heat will then be dissipated to the external environment through the radiator 300 to achieve heat dissipation for the power motor 100.

[0160] refer to Figure 6 and Figure 8 In some embodiments, the electric engine 22 may further include a liquid supply pipe 310 and a liquid return pipe 320. The outlet end of the liquid cooling channel is connected to the inlet end of the radiator 300 through the liquid return pipe 320, and the outlet end of the radiator 300 is connected to the inlet end of the liquid cooling channel through the liquid supply pipe 310. The liquid cooling channel, the liquid return pipe 320, the radiator 300 and the liquid supply pipe 310 form a circulation loop. In this way, the cooling medium can flow between the radiator 300 and the liquid cooling channel, thereby improving the heat dissipation efficiency.

[0161] In some embodiments, the liquid supply pipe 310 and the liquid return pipe 320 are both rigid pipes, and the radiator 300 is rigidly connected to the power motor 100 through the liquid supply pipe 310 and the liquid return pipe 320. It can be seen that the liquid supply pipe 310 and the liquid return pipe 320 constitute a supporting structure to fix the radiator 300 on the power motor 100.

[0162] refer to Figure 6 and Figure 8 In some embodiments, the electric engine 22 may further include a liquid pump 330 , which is disposed on the power motor 100 , and the liquid pump 330 is located on the circulation loop and is used to drive the flow of the cooling medium on the circulation loop.

[0163] In this way, by setting a liquid pump 330 on the circulation loop, the flow speed of the cooling medium in the circulation loop can be increased, thereby accelerating the circulation speed of the cooling medium in the circulation loop, thereby improving the heat dissipation efficiency of the radiator 300 and further improving the heat dissipation effect of the electric motor 22.

[0164] refer to Figure 6 and Figure 8In some embodiments, the first output end of the drive motor 200 is transmission-connected to the fan 400, and the second output end of the drive motor 200 is transmission-connected to the liquid pump 330. The drive motor 200 is used to drive the fan 400 to rotate and enable the liquid pump 330 to drive the cooling medium to flow.

[0165] In this way, by driving the fan 400 to rotate through the driving motor 200, and driving the liquid pump 330 to work through the driving motor 200, it is possible to simultaneously drive the fan 400 and the liquid pump 330 to work through one driving motor 200. Compared with the fan 400 and the liquid pump 330 being driven by independent driving motors 200 respectively, the number of components in the electric motor 22 is reduced, and the manufacturing cost and volume of the electric motor 22 are reduced.

[0166] In some embodiments, the driving motor 200 may further include a rotating shaft, with two ends of the rotating shaft being respectively a first output end and a second output end.

[0167] In some embodiments, the driving motor 200 may be a pump motor having a second output terminal, so that the pump motor drives the liquid pump 330 to work through the second output terminal. The electric engine 22 may also include another independent motor different from the pump motor, the motor having a first output terminal, and the motor can drive the fan 400 to rotate through the first output terminal.

[0168] Based on the above embodiment, Fig.13 It can be seen from the air flow velocity distribution diagram at different positions on the electric engine 22 simulated in the figure that by setting the guide structure 500 in the electric engine 22, when the electric engine 22 is running, the difference in the flow velocity of the air flow in the middle area of ​​the fan 400 and the flow velocity of the air flow in other areas of the fan 400 is significantly reduced, and the air flow distribution on the radiator 300 is more uniform, thereby effectively solving the heat reflux phenomenon caused by the flow velocity difference, improving the heat dissipation effect of the electric engine 22, and improving the reliability of the electric engine 22.

[0169] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0170] In this application, unless otherwise clearly specified and limited, the terms "installation", "connection", "fixation" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, it can be a connection between two elements or an interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0171] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0172] In the above description, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0173] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. An electric motor, characterized in that: include: Power motor; Drive motor; A radiator, the radiator having air ducts and used for dissipating heat from the power motor; A fan, the fan is drivingly connected to the driving motor, and the driving motor is used to drive the fan to rotate; A flow guide structure, wherein along the axial direction of the fan, the flow guide structure has an air inlet side and an air outlet side, and the drive motor and the power motor are both located on the air inlet side of the flow guide structure; The fan and the radiator are both located on the air outlet side of the air guide structure, and the fan is located between the air guide structure and the radiator; The flow guiding structure is used to guide at least part of the airflow on the air inlet side to the middle area of ​​the fan.

2. The electric motor according to claim 1, characterized in that: The guide structure includes a first guide path and a second guide path. The first guide path is used to guide the airflow on the air inlet side to the fan along a vertical direction, and the second guide path is used to guide part of the airflow on the air inlet side from the outside of the guide structure to the inside of the guide structure, and from the inside to the middle area of ​​the fan.

3. The electric motor according to claim 2, characterized in that: The guide structure comprises a plurality of guide fins, one ends of the plurality of guide fins are connected, and the other ends of the plurality of guide fins are arranged at intervals along the circumference of the fan; Each of the guide fins is arranged to be inclined relative to the central axis of the fan, so that the first guide path and the second guide path are formed between the guide fins.

4. The electric motor according to claim 3, characterized in that: The angle between the guide fin and the central axis of the fan is greater than or equal to 5° and less than or equal to 15°; or the fan includes fan blades, and along the radial direction of the fan, the horizontal distance between the outer edge of the fan blade and the outer side wall of the radiator is L1, and the horizontal distance between the outer edge of the guide fin and the outer side wall of the radiator is L2, and L1≥L2.

5. The electric motor according to any one of claims 1 to 4, characterized in that: The fan comprises: A wheel hub, the wheel hub being drivingly connected to the drive motor; A plurality of fan blades, the plurality of fan blades are arranged at intervals along the circumference of the hub and connected to the hub; At least one group of airflow channels is formed on the hub, and the airflow channels are used to guide at least part of the airflow directed to the middle area of ​​the fan to the heat sink.

6. The electric motor according to claim 5, characterized in that The number of the airflow channels is two groups, the two groups of airflow channels are respectively a first group of airflow channels and a second group of airflow channels, and the first group of airflow channels and the second group of airflow channels are spaced apart and distributed along the radial direction of the hub; And the first group of air flow channels is close to the center of the wheel hub; the first group of air flow channels includes a plurality of circular through holes, and the plurality of circular through holes are distributed around the circumference of the wheel hub; or the second group of air flow channels includes a plurality of special-shaped through holes, and the plurality of special-shaped through holes are distributed around the circumference of the wheel hub.

7. The electric motor according to claim 5, characterized in that The flow guide structure is fixedly connected to the housing of the power motor; Alternatively, it further comprises a fan cover, the air guide structure is fixedly connected to the fan cover, and the fan cover is fixedly connected to the radiator or the housing of the power motor.

8. The electric motor according to any one of claims 1 to 4, characterized in that: The power motor has a liquid cooling channel; The outlet end of the liquid cooling channel is connected to the inlet end of the radiator, and the outlet end of the radiator is connected to the inlet end of the liquid cooling channel. The liquid cooling channel and the radiator form a cooling medium circulation loop.

9. The electric motor according to claim 8, characterized in that The electric engine also includes a liquid supply pipe and a liquid return pipe; The outlet end of the liquid-cooling channel is connected to the inlet end of the radiator through the liquid return pipe, and the outlet end of the radiator is connected to the inlet end of the liquid-cooling channel through the liquid supply pipe. The liquid-cooling channel, the liquid return pipe, the radiator and the liquid supply pipe form the circulation loop; the liquid supply pipe and the liquid return pipe are both rigid pipes, and the radiator is rigidly connected to the power motor through the liquid supply pipe and the liquid return pipe.

10. The electric motor according to claim 8, characterized in that The electric engine further comprises a liquid pump, which is arranged on the power motor and located on the circulation loop and is used to drive the cooling medium on the circulation loop to flow; The first output end of the driving motor is drivingly connected to the fan, and the second output end of the driving motor is drivingly connected to the liquid pump. The driving motor is used to drive the fan to rotate and enable the liquid pump to drive the cooling medium to flow.

11. An electric propulsion device, characterized in that: comprising a propeller and an electric motor as claimed in any one of claims 1 to 10; The propeller is drivingly connected to the power motor of the electric engine, and the power motor is used to drive the propeller to rotate.

12. The electric propulsion device according to claim 11, characterized in that: Also includes: Fairing; The propeller has a blade, and the blade includes a blade root portion, and the blade root portion is located outside the fairing, and the blade root portion cooperates with the fairing; The propeller root is a plate-shaped structure; the angle between the width extension direction of the propeller root and the central axis of the fairing is less than 55°.

13. The electric propulsion device according to claim 12, characterized in that: A plurality of flow paths are formed between the blades and the wind inlet side of the guide structure of the electric motor, and the flow paths are used to transfer the airflow generated by the blades to the wind inlet side of the guide structure through the power motor.

14. The electric propulsion device according to claim 13, characterized in that: The power motor includes a stator and a rotor, an air gap is formed between the rotor and the stator, and a first flow path is formed between the blade and the air inlet side of the guide structure of the electric engine through the air gap; And / or, a rotor through hole is provided on the rotor, and a second flow path is formed between the blade and the air inlet side of the guide structure of the electric engine through the rotor through the rotor through hole; And / or, a third flow path is formed between the blade and the wind inlet side of the guide structure of the electric engine on the outer peripheral side of the power motor.

15. An aircraft, characterized in that: It comprises the electric propulsion device as claimed in any one of claims 11 to 14 and a fuselage, wings and tail, wherein the electric propulsion device is arranged on the wing and / or the fuselage and / or the tail.

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