Motor assembly, thrust assembly and aircraft

Abstract

The present invention discloses a motor assembly, a thrust assembly and an aircraft, and relates to the field of aircraft technology. In the motor assembly, one axial end of the outer rotor is a mechanical connection end, and the other axial end of the outer rotor is an open end; at least part of the inner stator extends from the open end into the outer rotor and is rotatably connected to the outer rotor, and the inner stator has a central axis hole that penetrates the inner stator along the axial direction of the inner stator; the cooling assembly is arranged on the side of the inner stator away from the mechanical connection end; the eccentric shaft is rotatably arranged in the central axis hole around its own central axis, the central axis of the eccentric shaft is parallel to the central axis of the central axis hole and spaced apart from each other, and one end of the eccentric shaft is transmission-connected to the cooling assembly, and the other end of the eccentric shaft is transmission-connected to the outer rotor, so that the outer rotor drives the cooling assembly through the eccentric shaft. The present invention eliminates the independent electric drive assembly of the cooling assembly and optimizes the overall weight of the motor assembly.

Description

Technical Field

[0001] The present invention relates to the technical field of aircraft, and in particular to a motor assembly, a thrust component and an aircraft. Background Art

[0002] The thrust assembly is the power source of the electric aircraft, which mainly includes the motor, motor controller and cooling assembly. The cooling assembly is used to promptly remove the heat generated by the motor during operation, improve the heat exchange efficiency, and thus improve the heat dissipation efficiency of the motor. Among them, the cooling assembly includes structures such as a cooling pump and a radiator.

[0003] However, the cooling assembly in the related art is driven by an independent driving mechanism, and the independent driving mechanism requires an additional power supply structure to be arranged in the thrust assembly, which results in a heavier overall weight of the thrust assembly. Summary of the invention

[0004] The main purpose of the present invention is to provide a motor assembly, a thrust assembly and an aircraft, aiming to solve the technical problem in the related art that the thrust assembly is heavy due to the use of an independent electric drive assembly for the cooling assembly.

[0005] To achieve the above object, the present invention provides a motor assembly, comprising:

[0006] An outer rotor, one axial end of the outer rotor is a mechanical connection end, and the other axial end of the outer rotor is an open end;

[0007] An inner stator, at least a portion of which extends from an open end into the outer rotor to be rotatably connected to the outer rotor, and the inner stator has a central axial hole that penetrates the inner stator along the axial direction of the inner stator;

[0008] A cooling assembly, the cooling assembly is arranged on a side of the inner stator away from the mechanical coupling end;

[0009] An eccentric shaft is rotatably arranged in the central shaft hole around its own central axis, the central axis of the eccentric shaft is parallel to the central axis of the central shaft hole and spaced apart from each other, and one end of the eccentric shaft is transmission-connected to the cooling assembly, and the other end of the eccentric shaft is transmission-connected to the outer rotor, so that the outer rotor drives the cooling assembly through the eccentric shaft.

[0010] In one embodiment, the outer rotor comprises:

[0011] A cylindrical member with both ends of the axial direction open;

[0012] The motor front cover is provided with a cover hole penetrating the motor front cover, and the motor front cover is fixedly arranged at one axial end of the cylindrical member to form a mechanical connection end, and the other axial end of the cylindrical member is opened to form an open end;

[0013] A rotating shaft, at least part of which is disposed in the cylindrical member and fixedly connected to the front cover of the motor, the rotating shaft is provided with a rotating shaft hole penetrating the rotating shaft, and the rotating shaft and the front cover of the motor are coaxially arranged so that the rotating shaft hole is connected to the cover hole to form a first wiring hole;

[0014] The rotating shaft is located outside the central shaft hole and is rotatably connected to an end of the inner stator close to the mechanical connection end through a bearing.

[0015] In one embodiment, the motor assembly further includes:

[0016] A first inner gear ring, the first inner gear ring is fixedly connected to an end surface of the rotating shaft close to the open end, and the central axis of the first inner gear ring is colinear with the central axis of the rotating shaft;

[0017] The matching gear is fixedly sleeved on the other end of the eccentric shaft and is meshed with the first inner gear ring.

[0018] In one embodiment, the motor assembly further includes:

[0019] A support cover, the support cover is fixedly arranged at the opening of the central shaft hole near the mechanical connection end, a part of the surface of one side end surface of the support cover protrudes to form a protrusion, and the protrusion is provided with a second wiring hole that penetrates the support cover along the axial direction of the inner stator to connect the first wiring hole and the central shaft hole;

[0020] The protrusions are located radially outside the mating gear and are spaced apart from each other.

[0021] In one embodiment, the cross-section of the second wiring hole is arc-shaped and partially surrounds the matching gear.

[0022] In one embodiment, a first coolant flow channel is defined in the inner stator, and the motor assembly further comprises a rear cover, which is arranged on a side of the inner stator away from the mechanical coupling end, and has a coolant inlet and a coolant outlet communicated with the first coolant flow channel;

[0023] The cooling package includes:

[0024] A radiator assembly, the radiator assembly includes a radiator and a cooling fan, the radiator is arranged on a side of the rear cover away from the inner stator and is spaced apart from each other, and a coolant heat dissipation channel in the radiator is respectively connected to a coolant inlet and a coolant outlet to be connected to the first coolant channel to form a circulation channel;

[0025] A cooling pump, the cooling pump is arranged between the radiator and the inner stator, and the cooling pump is used to drive the coolant to flow in the coolant heat dissipation channel and the first coolant channel;

[0026] Wherein, the cooling pump and the cooling fan are both connected with the eccentric shaft by transmission.

[0027] In one embodiment, the radiator assembly further includes at least three coolant pipes, one end of the coolant pipe is fixedly connected to the radiator and communicates with the coolant heat dissipation channel, and the other end of the coolant pipe is fixedly connected to the rear cover and communicates with the coolant inlet or the coolant outlet;

[0028] The coolant flowing through the radiator enters the first coolant flow channel through the coolant inlet.

[0029] In one embodiment, the heat dissipation fan is located on one end surface of the heat dissipator close to the inner stator and is spaced apart from the heat dissipation fan, and the heat dissipation fan includes an impeller shaft;

[0030] The cooling pump comprises a first gear shaft, and the impeller shaft is coaxial with the first gear shaft and fixedly connected to each other;

[0031] The eccentric shaft is transmission-connected to the impeller shaft or the first gear shaft.

[0032] In one embodiment, the cooling pump is an internal gear pump, which further includes a second internal gear ring and a first gear, the second internal gear ring is meshed with the first gear, and the first gear is fixedly sleeved on the first gear shaft; wherein the second internal gear ring is transmission connected to the eccentric shaft.

[0033] In one embodiment, the cooling pump is an external gear pump, and the cooling pump further includes a first gear and a second gear, the first gear is fixedly sleeved on the first gear shaft, and the second gear is meshed with the first gear, wherein the second gear or the first gear is transmission-connected to the eccentric shaft

[0034] In one embodiment, the central axis of the first gear shaft is colinear with the central axis of the inner stator.

[0035] In one embodiment, the cooling assembly further comprises:

[0036] The speed regulating gear set is arranged on the side of the rear cover away from the inner stator, and the eccentric shaft is transmission-connected with the cooling assembly through the speed regulating gear set.

[0037] In one embodiment, the cooling pump includes a pump body, which is arranged on an end surface of a rear cover away from the inner stator, and a gear cavity and a pump cavity are sequentially defined in the pump body along a direction from the inner stator to the cooling assembly, and the pump cavity is connected to a circulation channel;

[0038] Wherein, the speed regulating gear set is arranged in the gear cavity.

[0039] In one embodiment, the motor assembly further includes a motor controller, which is disposed in the central shaft hole, and defines an accommodation space extending along the axial direction of the inner stator;

[0040] Wherein, part of the eccentric shaft is arranged in the accommodating space.

[0041] In one embodiment, a second coolant flow channel is defined in the motor controller, and the second coolant flow channel is connected in series or in parallel with the first coolant flow channel and then communicated with the coolant heat dissipation flow channel.

[0042] In one embodiment, when the second coolant flow channel is connected in series with the first coolant flow channel, the first coolant flow channel includes a stator bottom plate flow channel and a winding flow channel that are connected in sequence, the winding flow channel includes a liquid cooling cavity defined in a stator shell of the inner stator, the stator core and the winding of the inner stator are both arranged in the liquid cooling cavity, and the second coolant flow channel is configured as an electric control board flow channel;

[0043] A first rear cover flow channel and a second rear cover flow channel are defined in the rear cover, one end of the first rear cover flow channel is connected to the coolant inlet, and the other end of the first rear cover flow channel is connected to the second coolant flow channel; one end of the second rear cover flow channel is connected to the winding flow channel, and the other end of the second rear cover flow channel is connected to the coolant outlet.

[0044] In addition, the present invention also provides a thrust assembly, comprising:

[0045] A motor assembly as above; and

[0046] The propeller assembly is connected to the mechanical connection end of the motor assembly.

[0047] In one embodiment, the propeller assembly comprises:

[0048] A propeller hub, the propeller hub is fixedly connected to the mechanical connection end, and an axial through hole is defined in the propeller hub;

[0049] A variable pitch motor, which is disposed in the axial through hole and is fixedly connected to an inner stator of the motor assembly; and

[0050] A connecting cable, one end of which is connected to the variable pitch motor, and the other end of which passes through the first wiring hole of the motor assembly and extends into the inner stator to be connected to the control module.

[0051] In addition, the present invention also provides an aircraft, the aircraft comprising:

[0052] Aircraft airframe; and

[0053] At least one thrust assembly as described above, the thrust assembly is arranged on the aircraft body.

[0054] In one embodiment, the aircraft is an electric vertical take-off and landing aircraft.

[0055] One or more technical solutions proposed in the present invention have at least the following technical effects:

[0056] In the technical solution of the motor assembly of the present invention, an eccentric shaft is added to the existing space in the inner stator of the outer rotor motor, that is, in the central axis hole in the inner stator that penetrates the inner stator along the axial direction of the inner stator. The eccentric shaft transmission connects the outer rotor with a cooling component that takes away the heat generated during the operation of the motor, so that the cooling component is driven by the outer rotor in the motor assembly, eliminating the independent electric drive component of the cooling component and the required circuit wiring structure in the related technology, thereby optimizing the overall weight of the motor assembly.

[0057] In addition, the eccentric shaft is arranged eccentrically in the central shaft hole, leaving enough space for cable routing.

[0058] In addition, the outer rotor drives the cooling assembly through the eccentric shaft of the mechanical transmission structure, which has higher reliability and safety compared to independent electric drive components.

[0059] In addition, in the present invention, the control module that provides electric energy and transmits control signals to the variable pitch motor is integrated into the inner stator, which can facilitate the assembly of the thrust assembly, help reduce the assembly process, and improve assembly efficiency. In addition, the control module of the variable pitch motor is integrated into the motor controller of the electric engine, and through a unified control architecture, the system design is simplified and the control efficiency is improved, the development and maintenance costs are reduced, and the maintainability of the thrust assembly is improved. Of course, it is also convenient to configure the two redundantly, thereby improving safety. In addition, the control module of the variable pitch motor is arranged in the inner stator, which has a high degree of integration in a limited installation space, and the cooling component of the electric engine can also be used to obtain a better cooling effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0061] Figure 1 A schematic diagram of the motor assembly structure provided by the present invention;

[0062] Figure 2 An exploded schematic diagram of the motor assembly provided by the present invention;

[0063] Figure 3 A schematic diagram of the positions of a support cover, a matching gear and a first inner gear ring in the motor assembly provided by the present invention;

[0064] Figure 4 An exploded schematic diagram of a support cover, a matching gear and a first inner gear ring in the motor assembly provided by the present invention;

[0065] Figure 5 A schematic diagram of the coolant flow direction of the motor assembly provided by the present invention, wherein the eccentric shaft is not shown;

[0066] Figure 6 A schematic diagram of the coordination between the speed regulating gear set and the external gear pump in the motor assembly provided by the present invention;

[0067] Figure 7 A schematic diagram of the structure of a cooling pump in a motor assembly provided by the present invention;

[0068] Figure 8 This is a schematic diagram of the coordination between the speed regulating gear set and the internal gear pump in the motor assembly provided by the present invention.

[0069] Description of Figure Numbers:

[0070] 10. Outer rotor; 101. Mechanical coupling end; 102. Open end; 103. First wiring hole; 11. Cylindrical member; 12. Rotating shaft; 13. Motor front cover; 20. Inner stator; 21. Center axis hole; 22. First coolant flow channel; 221. Stator bottom plate flow channel; 222. Winding flow channel; 30. Cooling assembly; 31. Cooling pump; 311. Pump body; 312. First gear shaft; 313. First gear; 314. Second gear; 315. Second inner gear ring; 311A. Gear cavity; 311B. Pump cavity ; 32. Radiator assembly; 321. Cooling fan; 322. Radiator; 323. Coolant pipe; 41. Eccentric shaft; 42. First inner gear ring; 43. Matching gear; 441. Support lower cover; 4441. Lower protrusion; 442. Support upper cover; 4421. Upper protrusion; 45. Second wiring hole; 50. Rear cover; 51. First rear cover flow channel; 52. Second rear cover flow channel; 60. Speed ​​regulating gear set; 61. Driving gear; 62. Output gear; 70. Motor controller; 71. Second coolant flow channel.

[0071] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0072] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0073] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0074] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0075] The motor will generate a lot of heat when in use. In the related art, the motor can be cooled by air cooling (fan forced cooling, etc.), liquid cooling (coolant such as water or oil), and combined cooling. Fan forced cooling is to add a fan to the motor and use the wind generated by the fan to force the motor to dissipate heat. Liquid cooling is to drive coolant such as water to flow through the inside of the motor through a pumping structure to absorb heat. Combined cooling combines air cooling and liquid cooling to improve the cooling effect. It can be understood that both the fan and the pumping mechanism require additional drive structures to drive their operation, and the aforementioned drive structure also requires additional circuit structures and wiring to be arranged on the motor to power the fan and the pumping mechanism.

[0076] When a rotor configuration is used on large UAVs and eVTOL (electric Vertical Take-off and Landing) and other aircraft, the rotor assembly and other thrust components are driven by an outer rotor motor. Since the power motor is a high-power heat-generating device, the heat dissipation requirement of the thrust component is higher, so the outer rotor motor in the thrust component generally adopts a combined cooling method. However, the aircraft is more sensitive to the overall weight. At this time, the combined cooling component is driven by an independent drive mechanism and an additional power supply architecture, which will cause the overall weight of the thrust component to be heavier, and then the overall weight of the aircraft to be heavier. In addition, the electric vertical take-off and landing aircraft has high requirements for space layout due to the configuration requirements. How to meet the heat dissipation requirements of high-power heat-generating devices and the reasonable arrangement of cooling components in a limited space has become a technical problem that technical personnel in this field urgently need to solve.

[0077] To this end, the present invention provides a motor assembly, which adds an eccentric shaft in the existing space in the inner stator of the outer rotor motor, that is, in the central axis hole in the inner stator that penetrates the inner stator along the axial direction of the inner stator. The eccentric shaft transmission connects the outer rotor with a cooling component that takes away the heat generated when the motor is running, so that the cooling component is driven by the outer rotor in the motor assembly, eliminating the independent electric drive component and the required circuit wiring structure, thereby optimizing the overall weight of the motor assembly.

[0078] See also Figure 1 and Figure 2 This embodiment provides a motor assembly, including an outer rotor 10, an inner stator 20, a cooling assembly 30 and an eccentric shaft 41.

[0079] Among them, one axial end of the outer rotor 10 is a mechanical connection end 101, and the other axial end of the outer rotor 10 is an open end 102; at least a portion of the inner stator 20 extends from the open end 102 into the outer rotor 10 and is rotatably connected to the outer rotor 10, and the inner stator 20 has a central axis hole 21 that penetrates the inner stator 20 along the axial direction of the inner stator 20; the cooling assembly 30 is arranged on the side of the inner stator 20 away from the mechanical connection end 101; the eccentric shaft 41 is rotatably arranged in the central axis hole 21 around its own central axis, the central axis of the eccentric shaft 41 is parallel to the central axis of the central axis hole 21 and spaced apart from each other, and one end of the eccentric shaft 41 is transmission-connected to the cooling assembly 30, and the other end of the eccentric shaft 41 is transmission-connected to the outer rotor 10, so that the outer rotor 10 drives the cooling assembly 30 through the eccentric shaft 41.

[0080] Specifically, the motor in this embodiment is an outer rotor motor. The rotor of the outer rotor motor forms an outer rotor 10 on the outside, and the stator forms an inner stator 20 on the inside. Among them, the inner stator 20 includes a stator housing, a stator core and windings. The stator core and the windings are both installed in the stator housing, and the windings are embedded in the stator slots of the stator core. The stator housing is formed into a U-shaped housing. At this time, the shaft hole of the stator housing forms a central shaft hole 21, that is, the central axis of the central shaft hole 21 is collinear with the central axis of the inner stator 20. It can be understood that the axial direction of the inner stator is the axial direction of the motor assembly.

[0081] The outer rotor 10 is generally constructed as a tubular member with one side open, and its open side forms an open end 102, so that the inner stator 20 can be installed into the outer rotor 10 from the open end 102. A plurality of magnetic poles are fixed on the inner peripheral surface of the outer rotor 10. It can be understood that the outer rotor 10 forms the front cover of the motor and covers one end of the inner stator 20. Correspondingly, the other side of the outer rotor 10 is a mechanical connection end 101, and the mechanical connection end 101 is used to transmit force, motion and torque to the outside. When the motor assembly in this embodiment is used as the drive motor of the thrust component of the aircraft, the mechanical connection end 101 is connected to the hub of the propeller to transmit power, so that the propeller generates the lift and thrust required for flight.

[0082] The other end of the inner stator 20 can be covered by a rear cover 50. The rear cover 50 is used to enclose the inner stator 20 to prevent foreign objects from entering the motor interior, so as to form a storage space inside the inner stator 20 that can be used to arrange corresponding circuit boards or other line structures (such as control modules). In addition, the rear cover 50 is also provided with a coolant outlet and a coolant inlet, so that the coolant can enter the inner stator 20 through the rear cover 50 after being cooled by the cooling component 30 on one side of the rear cover 50, or the coolant can flow into the cooling component 30 through the rear cover 50 after heat exchange with the windings for cooling, which will be elaborated in detail below.

[0083] Of course, the rear cover 50 may not be provided at the other end of the inner stator 20, and the cooling component 30 may be used as the rear cover 50 of the motor, and this embodiment does not limit this.

[0084] Since the central shaft hole 21 inside the inner stator 20 communicates with both axial ends of the inner stator 20, and the outer rotor 10 and the cooling component 30 are respectively located on both axial sides of the inner stator 20, in this embodiment, a part of the eccentric shaft 41 is arranged in the central shaft hole 21, and one end extends to the mechanical connection end to be传动 connected to the outer rotor 10, and the other end extends to the cooling component to be传动 connected to the cooling component 30, so as to transmit the rotational motion of the outer rotor 10 to the cooling component 30 to drive the air-cooling component and / or the liquid-cooling component of the cooling component 30 to start running.

[0085] It is not difficult to see that in this embodiment, an eccentrically arranged eccentric shaft 41 is added to the existing space in the inner stator 20 of the outer rotor motor, that is, the central axis hole 21 in the inner stator 20 that penetrates the inner stator 20 along the axial direction of the inner stator 20. The eccentric shaft 41 drives the outer rotor 10 to the cooling assembly 30 that takes away the heat generated when the motor is running, so that the cooling assembly 30 is driven by the outer rotor 10 in the motor assembly, eliminating the independent electric drive assembly and the required circuit wiring structure, thereby optimizing the overall weight of the motor assembly. In addition, the outer rotor 10 drives the cooling assembly 30 through the eccentric shaft 41 of the mechanical transmission structure, which is more reliable and safe than the independent electric drive assembly.

[0086] In addition, most of the eccentric shaft 41 in this embodiment is arranged in the central shaft hole 21 in the inner stator 20, and the existing structure and layout of the motor and cooling component 30 in the motor assembly are not changed, which is conducive to promotion and use in existing products.

[0087] In addition, this embodiment eliminates the independent electric drive assembly required for the cooling assembly 30, and can also avoid the heat dissipation problem and heat dissipation risk of the independent drive motor.

[0088] In one embodiment, the mechanical connection end 101 of the outer rotor 10 is provided with a first wiring hole 103 communicating with the central shaft hole 21 .

[0089] Specifically, see Figure 1 , the first wiring hole 103 is used for laying the corresponding cables. After the mechanical connection end 101 is connected to the action element (such as a propeller), one end of the cable passes through the central axis hole 21 and the first wiring hole in sequence and extends to the outside of the motor assembly to connect with the corresponding cable interface on the action element. The other end of the cable can be connected to the control module in the inner stator 20. It can be understood that the cable can be a power supply cable, a communication cable, or a power supply and communication two-in-one cable, and this embodiment does not limit this.

[0090] In addition, since a cable is arranged in the central shaft hole 21, in order to avoid interference between the eccentric shaft 41 and the cable, the eccentric shaft 41 is eccentrically arranged in the central shaft hole 21, that is, the central axis of the eccentric shaft 41 is parallel to the central axis of the central shaft hole 21 and is spaced apart from each other. And the eccentric shaft 41 rotates around its own central axis in the central shaft hole 21, that is, the eccentric shaft 41 gives up the axial position of the central shaft hole 21 and only occupies a space at an eccentric position, so that there is sufficient space in the central shaft hole 21 for laying cables.

[0091] It should be noted that the motor can be a dual-bearing motor or a single-bearing motor. In one embodiment, when the motor is a dual-bearing motor, the outer rotor 10 includes a cylindrical member 11 and a rotating shaft 12, one end of the cylindrical member 11 is open to form an open end 102; the rotating shaft 12 extends along the axial direction of the inner stator 20, at least part of the rotating shaft 12 is arranged in the cylindrical member 11 and is fixedly connected to the cylindrical member 11, and the end of the rotating shaft 12 close to the open end 102 passes through the central axis hole 21 and extends to the side of the inner stator 20 away from the mechanical connection end 101; the motor assembly also includes a first bearing and a second bearing, the end of the rotating shaft 12 close to the mechanical connection end 101 is rotatably connected to the end of the inner stator 20 close to the mechanical connection end 101 through the first bearing, and the end of the rotating shaft 12 away from the mechanical connection end 101 is rotatably connected to the end of the inner stator 20 away from the mechanical connection end 101 through the second bearing.

[0092] Specifically, a hollow tubular stator bracket is provided in the central axis hole 21 of the inner stator 20, and the stator bracket is fixedly connected to the inner peripheral wall of the stator core of the inner stator 20 through a plurality of arms protruding from its outer peripheral wall, one end of the stator bracket protrudes from the end of the inner stator 20 away from the mechanical connection end 101 and is installed with a second bearing, and the end of the inner stator 20 close to the mechanical connection end 101 is installed with a first bearing. At this time, the rotating shaft 12 of the outer rotor 10 is installed in the stator bracket and its two ends are respectively matched with the first bearing and the second bearing. In this embodiment, the eccentric shaft 41 can be located in the stator bracket and arranged eccentrically compared to the central axis of the stator bracket.

[0093] Of course, it is understandable that for an aircraft, in order to reduce the weight of the entire machine, a single-bearing motor is preferably used as the motor. The following also takes the motor as a single-bearing motor as an example for explanation. Therefore, in another embodiment, the outer rotor 10 includes: a cylindrical member 11 with open axial ends, a motor front cover 13, and a rotating shaft 12. The motor front cover 13 is provided with a cover hole that penetrates the motor front cover 13. The motor front cover 13 is fixedly arranged at one axial end of the cylindrical member 11 to form a mechanical connection end 101, so that the other axial end of the cylindrical member 11 is open to form an open end 102; at least part of the rotating shaft 12 is arranged in the cylindrical member 11 and is fixedly connected to the motor front cover 13. The rotating shaft 12 and the motor front cover 13 are coaxially arranged so that the rotating shaft hole is connected to the cover hole to form a first wiring hole 103. The rotating shaft 12 is located outside the central shaft hole 21, and is rotatably connected to the end of the inner stator 20 close to the mechanical connection end 101 through a bearing.

[0094] Specifically, see Figure 2 The cylindrical member 11 and the motor front cover 13 together form a motor housing, and the motor front cover 13 is provided at one axial end of the cylindrical member 11 to form a mechanical connection end 101, while the other axial end is open to form an open end 102. A cover hole is provided at the center of the motor front cover 13 to penetrate the motor front cover 13 along the axial direction of the inner stator 20.

[0095] The outer rotor 10 further includes a rotating shaft 12, the central axis of the rotating shaft 12 is colinear with the central axis of the inner stator 20. It is worth mentioning that at least part of the rotating shaft 12 is disposed in the cylindrical member 11, and the rotating shaft 12 may be partially disposed in the cylindrical member 11, such as a part of the rotating shaft 12 is located in the cylindrical member 11, and the other part protrudes from the motor front cover 13 and is located outside the cylindrical member 11.

[0096] Alternatively, see Figure 1 and Figure 2 , it is also possible that the rotating shaft 12 is completely arranged in the cylindrical member 11, in which case the rotating shaft 12 is arranged in the cylindrical member 11 and extends along the axial direction of the inner stator 20, and one axial end of the rotating shaft 12 is fixedly connected to the cover hole of the motor front cover 13 by a bolt group. The other end of the rotating shaft 12 is rotatably connected to one end of the inner stator 20 toward the mechanical connection end 101 through a bearing, so that the outer rotor motor of the motor assembly provided in this embodiment is a single-bearing motor. The hole wall of the rotating shaft hole of the rotating shaft 12 and / or the end surface of the rotating shaft 12 on one side away from the inner stator are provided with a connection structure to form a mechanical connection end 101. As in one example, the installation structure of the propeller system passes through the cover hole of the motor front cover 13 to the rotating shaft 12 and is connected to the rotating shaft.

[0097] In this embodiment, when the propeller system transmits the overturning moment through the connection structure on the rotating shaft 12, a part of the overturning moment is transmitted to the motor front cover 13 and the cylindrical member 11 through the rotating shaft 12, and the other part of the overturning moment is transmitted to the inner stator 20 through the rotating shaft 12 and the bearing. Since the connection structure is located in the rotating shaft hole, the deformation caused by the overturning moment can be resisted by the structural reinforcement design (such as increasing the wall thickness) at the connection between the rotating shaft 12, the inner stator 20 and the bearing, and the structural reinforcement design (such as increasing the wall thickness) at the connection between the cylindrical member 11 and the rotating shaft 12. In addition, the remaining part of the motor front cover 13 and the cylindrical member 11 can adopt a thin-walled design, so that when subjected to the overturning moment, a certain deformation is generated on the transmission path, which can reduce the deformation of the cylindrical member 11. Of course, since a single bearing design is adopted, in order to ensure the structural strength, the radius of the bearing, the outer rotor 10 and the inner stator 20 all need to be increased. However, relatively speaking, increasing the radius also increases the propeller installation circle radius, achieving the effect of improving the propeller system mass distribution and improving the overturning moment distribution.

[0098] It is easy to understand that the single-bearing motor in which the rotating shaft 12 is located outside the central shaft hole 21 significantly reduces the total weight of the motor assembly. In addition, the rotating shaft 12 is located outside the central shaft hole 21, and the central shaft hole 21 can also have sufficient space to arrange the electronic components of the motor. In this way, in this embodiment, the eccentric shaft 41 is installed in the central shaft hole 21 of the single-bearing motor, which can make full use of the existing space in the single-bearing motor, making the space utilization more reasonable. Of course, installing the eccentric shaft 41 and laying the cables in the central shaft hole 21 can also make the overall weight distribution of the motor assembly more uniform and reasonable compared to leaving the central shaft hole 21 empty.

[0099] In addition, since the eccentric shaft 41 rotates around its own central axis, and the central axis of the eccentric shaft 41 is staggered with the central axis of the rotating shaft 12, a corresponding transmission structure is also required to connect the rotating shaft 12 and the eccentric shaft 41 to transmit the rotational motion of the rotating shaft 12 to the eccentric shaft 41. It can be understood that the eccentric shaft 41 and the rotating shaft 12 belong to the transmission between different axes, so it can be realized by using a gear set or a transmission belt and other structures. However, structures such as transmission belts may occupy the space in the rotating shaft hole, thereby affecting the layout of the cables. Therefore, in one embodiment, the motor assembly also includes a first inner gear ring 42 and a matching gear 43, the first inner gear ring 42 is fixedly connected to an end face of the rotating shaft 12 close to the open end 102, and the central axis of the first inner gear ring 42 is colinear with the central axis of the rotating shaft 12; the matching gear 43 is fixedly sleeved on the other end of the eccentric shaft 41, and the matching gear 43 is meshed with the first inner gear ring 42.

[0100] Specifically, see Figure 2 , Figure 3 and Figure 4 The first inner gear ring 42 is fixed to the end face of the rotating shaft 12 close to the inner stator 20 by means of screws or other fasteners or welding, and the central axis of the first inner gear ring 42 is colinear with the central axis of the rotating shaft 12. The matching gear 43 is meshed with the first inner gear ring 42 in the first inner gear ring 42, and the matching gear 43 is fixedly sleeved on the end of the eccentric shaft 41 close to the rotating shaft 12. Therefore, when the rotating shaft 12 rotates, it drives the first inner gear ring 42 to rotate, and the rotation of the first inner gear ring 42 will drive the matching gear 43 to rotate around the central axis of the eccentric shaft 41, that is, drive the eccentric shaft 41 to rotate around its own central axis.

[0101] It is not difficult to see that in this embodiment, since the first inner gear ring 42 is an annular member and its interior is hollow, the first inner gear ring 42 does not occupy the front and rear space in the axial direction of the shaft hole, thereby leaving enough space for cable routing. In this way, the cable can pass through the first inner gear ring 42 and the first wiring hole 103 in sequence and extend to the outside of the motor assembly.

[0102] It is worth mentioning that in order to completely prevent the first inner gear ring 42 from affecting the cable routing, the inner diameter of the first inner gear ring 42 can be larger than the inner diameter of the rotating shaft 12, that is, the inner edge of the projection of the first inner gear ring 42 on the plane where the end face of the rotating shaft 12 is located is located radially outside the inner edge of the rotating shaft 12.

[0103] It is understandable that when the motor is running, the mating gear 43 will rotate at a high speed, and if the cable touches the mating gear 43, the cable will be damaged. Therefore, in one embodiment, the motor assembly further includes: a support cover, the support cover is fixedly arranged at the opening of the central shaft hole 21 close to the mechanical connection end 101, and a part of the surface of one side end surface of the support cover protrudes to form a protrusion, and the protrusion is provided with a second wiring hole 45 that passes through the support cover along the axial direction of the inner stator 20 to connect the first wiring hole 103 and the central shaft hole 21; wherein the protrusions are located radially outside the mating gear 43 and are spaced apart from each other.

[0104] Specifically, the support cover is located at the opening of the central shaft hole 21 near the rotating shaft 12, and an eccentric shaft bearing is installed on the support cover, and the eccentric shaft bearing cooperates with the eccentric shaft 41 to allow the eccentric shaft 41 to rotate relative to the support cover. Part of the surface of one side end face of the support cover protrudes outward from the radial outside of the mating gear 43 to form a protrusion, and a second wiring hole 45 for the cable to pass through is formed in the protrusion. The second wiring hole 45 provides an independent wiring space. In this way, when the cable passes near the mating gear 43, it is constrained and protected by the hole wall of the second wiring hole 45, thereby preventing the cable from being damaged by the mating gear 43 rotating at high speed.

[0105] As an option of this embodiment, the support cover may be fixed to the end face of one side of the inner stator 20 close to the mechanical coupling end 101. Part of the surface of the end face of one side of the support cover close to the mechanical coupling end 101 protrudes in a direction away from the inner stator 20 to form a protrusion. At this time, the eccentric shaft 41 penetrates the support cover and extends to the side of the support cover close to the rotating shaft 12 to connect with the matching gear 43.

[0106] Alternatively, as another option of this embodiment, the support cover may be constructed as a shell with an opening on one side, the shell is fixed to the end face of the inner stator 20 near the mechanical connection end 101, and the closed end of the shell protrudes and extends into the rotating shaft 12. Part of the surface of the inner end face of the closed end protrudes and extends in the direction close to the inner stator 20 to form a protrusion. At this time, an eccentric shaft bearing is installed on the inner end face of the closed end, and the eccentric shaft 41 extends to the outside of the central shaft hole 21 until it cooperates with the eccentric shaft bearing. Compared with the above method, the support cover of the shell structure can also cover the rotating shaft hole, so as to prevent foreign matter from entering the motor assembly from the rotating shaft hole and affecting the meshing of the mating gear 43 with the first inner gear ring, thereby improving the mating reliability of the mating gear 43 and the first inner gear ring 42.

[0107] Alternatively, as another option of this embodiment, see Figure 3 and Figure 4 The support cover includes an upper support cover 442 and a lower support cover 441. The lower support cover 441 is fixed to the end face of the inner stator 20 near the mechanical coupling end 101. A portion of the surface of the end face of the lower support cover 441 near the mechanical coupling end 101 protrudes in a direction away from the inner stator 20 to form a lower protrusion 4411. The upper support cover 442 is located in the rotating shaft 12 and is not connected to the rotating shaft 12. A portion of the surface of the end face of the upper support cover 442 near the inner stator 20 protrudes and extends in a direction close to the inner stator 20 to form an upper protrusion 4421. The upper protrusion 4421 stops at the lower protrusion 4411 and is fixedly connected to each other to form a protrusion. At this time, the upper support cover 442 and the lower support cover 441 define an accommodation space, and the matching gear 43 and the eccentric shaft bearing are both located in the accommodation space. It is not difficult to see that, compared with the two aforementioned methods in which only one side of the mating gear 43 is covered, the axial ends of the mating gear 43 in this embodiment are covered by the support upper cover 442 and the support lower cover 441, respectively, thereby further preventing foreign matter from entering the motor assembly from the shaft hole, or preventing the electronic components in the inner stator 20 from falling and moving to the mating gear 43 to affect the meshing of the mating gear 43 and the first inner gear ring 42, thereby improving the mating reliability of the mating gear 43 and the first inner gear ring 42. In addition, when the cable is laid, there is always a margin in length, that is, the cable is not a straight line in the motor assembly, but a curved shape. Therefore, the axial ends of the mating gear 43 are covered by the support upper cover 442 and the support lower cover 441, respectively, so that the cable in the second wiring hole 45 is protected by the hole wall of the second wiring hole 45, and the cable near the second wiring hole 45 is protected by the support upper cover 442 and the support lower cover 441, which jointly prevent the cable from being damaged by the mating gear 43 rotating at high speed.

[0108] The cross-sectional shape of the second wiring hole 45 can be a circular shape or the like. Of course, since the mating gear 43 has already occupied a portion of the space defined by the shaft hole, in order to allow the second wiring hole 45 to occupy more space in the remaining space to arrange more cables, in one embodiment, refer to Figure 4 The cross section of the second wiring hole 45 is arc-shaped and partially surrounds the matching gear 43.

[0109] As before, the cooling assembly 30 may include an air cooling assembly (such as a cooling fan 321), a liquid cooling assembly (such as a heat exchanger and a pumping assembly that pumps the coolant into the motor so that the coolant flows through the motor), or a combination of an air cooling assembly and a liquid cooling assembly. For example, when the motor assembly is configured as a drive motor for a propeller of a small drone, the cooling assembly 30 may only include an air cooling assembly. Alternatively, when the motor assembly is configured as a drive motor for a propeller on an eVTOL, the cooling assembly 30 may be a liquid cooling assembly or a combination of an air cooling assembly and a liquid cooling assembly.

[0110] In one embodiment, a first coolant flow channel 22 is defined in the inner stator 20 , and the motor assembly further includes a rear cover 50 , which is disposed on a side of the inner stator 20 away from the mechanical connection end 101 , and has a coolant inlet and a coolant outlet connected to the first coolant flow channel 22 .

[0111] The cooling component 30 includes: a radiator assembly 32 and a cooling pump 31. The radiator assembly 32 includes a radiator 322 and a cooling fan 321. The radiator 322 is arranged on the side of the rear cover 50 away from the inner stator 20 and are spaced apart from each other, and the coolant heat dissipation channel in the radiator 322 is respectively connected to the coolant inlet and the coolant outlet to connect with the first coolant channel 22 to form a circulation channel; the cooling pump 31 is arranged between the radiator 322 and the inner stator 20, and the cooling pump 31 is used to drive the coolant to flow in the coolant heat dissipation channel and the first coolant channel 22; wherein the cooling pump 31 and the cooling fan 321 are both transmission-connected to the eccentric shaft 41.

[0112] The coolant inlet and the coolant outlet of the first coolant flow channel 22 are both opened in the rear cover 50. In one example, the rear cover 50 is provided with a plurality of through holes, wherein the coolant inlet is near the center of the rear cover 50, and the coolant outlet is near the edge of the rear cover 50.

[0113] It is worth mentioning that the number of the first coolant flow channel 22 can be one, or multiple first coolant flow channels 22 can be connected in parallel to reduce the length of a single first coolant flow channel 22, thereby removing heat from the inner stator 20 as quickly as possible. Multiple first coolant flow channels 22 can achieve uniform flow distribution of the coolant by designing corresponding pipe diameters.

[0114] See also Figure 1 , Figure 2 and Figure 5 The radiator assembly 32 in the cooling component 30 is located on a side of the inner stator 20 away from the mechanical coupling end 101 and is spaced apart from each other, thereby leaving enough space for installing the cooling pump 31 and for air flow.

[0115] The connection relationship between the coolant heat dissipation channel, the first coolant channel 22 and the cooling pump 31 can be specifically that after the cooling pump 31 is connected to the coolant heat dissipation channel of the radiator 322, the cooling pump 31 is connected to the coolant inlet, and the coolant heat dissipation channel in the radiator 322 is connected to the coolant outlet. Alternatively, after the cooling pump 31 is connected to the coolant heat dissipation channel of the radiator 322, the cooling pump 31 is connected to the coolant outlet, and the coolant heat dissipation channel in the radiator 322 is connected to the coolant inlet. Alternatively, in order to simplify the connection relationship and facilitate the installation of the cooling pump 31, the coolant heat dissipation channel is connected to the first coolant channel 22, and the cooling pump 31 is arranged on the first coolant channel 22, so as to drive the coolant in the first coolant channel 22 to flow, thereby promoting the coolant to circulate in the coolant heat dissipation channel and the first coolant channel 22.

[0116] The coolant exchanges heat with the outside air in the coolant heat dissipation channel. The cooling fan 321 and the radiator 322 can be arranged in sequence in the axial direction of the inner stator 20, such as the radiator 322 is close to the inner stator 20 and the cooling fan 321 is far away from the inner stator 20. Alternatively, in order to promote sufficient heat exchange between the outside air and the radiator 322, the cooling fan 321 is close to the inner stator 20, and the radiator 322 is far away from the inner stator 20.

[0117] In one example, the cooling fan 321 is close to the inner stator 20 and the radiator 322 is arranged away from the inner stator 20, and the cooling pump 31 is located on the first coolant flow channel 22. At this time, the cooling pump 31 drives the low-temperature coolant to flow in the first coolant flow channel 22 in the inner stator 20, and absorbs the heat generated by the motor, especially the winding, and becomes a high-temperature liquid to remove the heat in the inner stator 20. After leaving the inner stator 20, the high-temperature liquid enters the radiator 322, and becomes a low-temperature coolant after heat exchange with the outside air in the radiator 322, thereby completing the heat dissipation cycle. The cooling fan 321 works on the side of the radiator 322 close to the inner stator 20, so that the outside air can flow through the surface of the radiator 322 to exchange heat. Alternatively, the cooling fan 321 can also cause air to flow through the inside or outside of the motor to take away heat.

[0118] In addition, the heat sink 322 can be connected to the inner stator 20 through an additional connection structure. Figure 1 The radiator assembly 32 also includes at least three coolant pipes 323, one end of the coolant pipe 323 is fixedly connected to the radiator 322 and communicated with the coolant heat dissipation channel, and the other end of the coolant pipe 323 is fixedly connected to the rear cover 50 and communicated with the coolant inlet or the coolant outlet; the coolant flowing through the radiator 322 enters the first coolant channel 22 through the coolant inlet.

[0119] Specifically, all the coolant pipes 323 can be return pipes for the coolant in the inner stator 20 to flow back to the radiator 322. At this time, the coolant in the radiator 322 flows into the inner stator 20 through the cooling pump 31. It can be understood that a plurality of coolant pipes 323 can be evenly spaced along the circumferential direction of the inner stator 20 to better stress the motor assembly as a whole.

[0120] Alternatively, when the cooling pump 31 is arranged on the first coolant flow channel 22, part of the coolant pipe 323 is a liquid outlet pipe, and the other part of the coolant pipe 323 is a liquid return pipe, and the liquid outlet pipe and the liquid return pipe are respectively fixedly connected to the radiator 322 and the inner stator 20. At this time, the radiator 322 includes a liquid outlet connected to the liquid outlet pipe in a one-to-one correspondence, and a liquid return port connected to the liquid return pipe in a one-to-one correspondence. In addition, the number of liquid outlet pipes and liquid return pipes can be the same and in groups of two. At this time, the liquid outlet pipe and the liquid return pipe can be evenly spaced and alternately arranged along the circumferential direction of the inner stator 20, so that the coolant can flow into the radiator from two opposite areas on the radiator 322, and flow out of the radiator from two opposite areas on the radiator 322, which is conducive to uniform heat dissipation of the coolant in the radiator 322.

[0121] In this embodiment, the coolant pipe 323 is not only a liquid pipeline, but also a structural component supporting and connecting the radiator 322 and the inner stator 20. It is an integrated design, thereby improving the integration of components and reducing the number of components.

[0122] In addition, when the cooling fan 321 is located on one side end surface of the radiator 322 facing the inner stator 20 and is spaced apart from the radiator 322, the number of the cooling fan 321 can be one or more. Preferably, when there is one cooling fan 321, the cooling fan 321 includes an impeller shaft; the cooling pump 31 includes a first gear shaft 312; the impeller shaft and the first gear shaft 312 are coaxial and fixedly connected to each other, wherein the eccentric shaft 41 is drivingly connected to the impeller shaft or the first gear shaft 312.

[0123] Generally speaking, the cooling fan 321 includes an impeller and an impeller shaft. The impeller rotates at high speed driven by the impeller shaft, thereby generating negative pressure to promote gas flow. There are many types of pumps, among which gear pumps and vane pumps both include a first gear shaft 312 that rotates around its own central axis. In this embodiment, please refer to Figure 1, the impeller shaft rotating around its own axis and the first gear shaft 312 rotating around its own axis are coaxial and fixedly connected to each other, so that when the eccentric shaft 41 is in transmission connection with the impeller shaft or the first gear shaft 312, the impeller shaft and the first gear shaft 312 can be driven to rotate together, so as to simultaneously drive the impeller of the cooling fan 321 and the first gear 313 of the cooling pump 31 to operate. It can be seen that this embodiment saves the transmission structure between the cooling fan 321 and the cooling pump 31, thereby simplifying the mechanical structure inside the motor assembly and reducing the overall weight.

[0124] It can be understood that, as an option of this embodiment, the impeller shaft and the first gear shaft 312 can be connected via a coupling.

[0125] Alternatively, as an alternative to this example, see Figure 1 , the impeller shaft and the first gear shaft 312 are an integrally formed part. At this time, the impeller shaft and the first gear shaft 312 are the same shaft, a part of which is located in the cooling pump 31, and the other part passes through the pump body 311 of the cooling pump 31 and extends toward the radiator 322, and the impeller of the cooling fan 321 is installed on the other part. It is easy to understand that compared with the connection method such as the coupling, the impeller shaft and the first gear shaft 312 are an integrally formed part, which can further reduce the number of parts of the motor assembly, making the size of the motor assembly in its axial direction smaller, and further reducing the overall weight.

[0126] In addition, after the impeller shaft and the first gear shaft 312 are coaxially arranged, both can be staggered with the central axis of the inner stator 20, that is, eccentrically arranged, or both can be collinear with the central axis of the inner stator 20, and this embodiment does not limit this. It can be understood that the eccentric arrangement is conducive to leaving space in the axial direction of the motor to arrange other components, and the collinear arrangement is conducive to making the radial shape of the motor assembly smaller and more regular, so as to facilitate arrangement on platforms such as aircraft that have higher requirements for aerodynamic shape. Of course, in the case where the eccentric shaft 41 is already eccentrically arranged, in order to facilitate the symmetrical design of the motor assembly, the central axes of the impeller shaft and the first gear shaft 312 are both collinear with the central axis of the inner stator 20.

[0127] As before, the cooling pump 31 can be an impeller pump or a gear pump, wherein the main working parts of the gear pump are the meshing gears. When the gears rotate, the change in the volume between the teeth forms a suction and discharge effect. The liquid is transported or pressurized by relying on the change in the working volume formed between the pump body 311 and the meshing gears, while the impeller pump relies on the impeller to drive the liquid to rotate at high speed to transfer mechanical energy to the transported liquid. Since the gear pump has a simple structure, reliable operation, and low price, it is suitable for occasions requiring high pressure and large flow. Therefore, when the motor assembly is suitable for aircraft, the cooling pump 31 can use a gear pump.

[0128] It can be understood that, as an option, the cooling pump 31 is an external gear pump, and the cooling pump 31 also includes a first gear 313 and a second gear 314, the first gear 313 is fixedly sleeved on the first gear shaft 312, and the second gear 314 is meshed with the first gear 313, wherein the second gear 314 or the first gear 313 is transmission connected to the eccentric shaft 41.

[0129] Specifically, the pump body 311 of the cooling pump 31 is fixed to the end surface of the rear cover 50 which is away from the inner stator 20. Figure 6 , a second gear 314 and a first gear 313 meshing with each other are installed in the pump body 311. Since the cooling pump 31 is closer to the eccentric shaft 41 than the cooling fan 321, the second gear 314 of the cooling pump 31 can be connected to the eccentric shaft 41 by transmission, so that the eccentric shaft 41 drives the second gear 314 to rotate, and the second gear 314 drives the first gear 313 to rotate, and then drives the impeller of the cooling fan 321 to rotate. Alternatively, the first gear 313 of the cooling pump 31 can be connected to the eccentric shaft 41 by transmission, so that the eccentric shaft 41 drives the first gear 313 to rotate, the first gear 313 drives the second gear 314 to rotate, and the first gear 313 drives the impeller of the cooling fan 321 to rotate. That is, in this embodiment, the first gear 313 or the second gear 314 can be used as the driving gear of the cooling pump 31, and this embodiment is not limited to this.

[0130] Alternatively, as another option, the cooling pump 31 is an internal gear pump, and the cooling pump 31 also includes a second inner gear ring 315 and a first gear 313, the first gear 313 is fixedly sleeved on the first gear shaft 312, and the second inner gear ring 315 is meshed with the first gear 313; wherein the first gear 313 is transmission connected to the eccentric shaft 41.

[0131] Generally speaking, the main parts of an internal gear pump are a pair of second internal gear rings 315 and external gears meshing with each other, and a crescent-shaped spacer. Figure 7 and Figure 8 In this embodiment, the second inner gear ring 315 rotates around its own axis under the drive of the eccentric shaft 41. The outer gear, that is, the first gear 313, is sleeved on the first gear shaft 312 and is an eccentric device relative to the central axis of the second inner gear ring 315. It acts as a driven gear and rotates under the drive of the second inner gear ring 315. The function of the crescent-shaped spacer is to separate the suction chamber and the discharge chamber. During operation, when the active second inner gear ring 315 rotates, a partial vacuum is formed where the gear teeth are disengaged, and the coolant enters the pump body 311 under the action of atmospheric pressure and fills the spaces between the teeth. Where the gear teeth are engaged, the coolant stored between the teeth is squeezed and discharged outside the pump body 311. Of course, the first gear 313 further drives the impeller of the cooling fan 321 to rotate through the first gear shaft 312.

[0132] Of the two aforementioned options, the internal gear pump and the external gear pump have a compact structure, small size, and good suction performance, which are more conducive to the motor assembly being suitable for platforms such as aircraft.

[0133] It is understandable that when the motor speed is consistent with the speed requirement of the cooling fan 321, the eccentric shaft 41 can be directly connected to the gear shaft and / or the impeller shaft in the cooling assembly 30, that is, no reducer or other structures are required. Alternatively, when the motor speed is different from the gear speed of the cooling pump 31 in the cooling assembly 30, in one embodiment, the cooling assembly 30 further includes: a speed regulating gear set 60, which is arranged on the side of the inner stator 20 away from the mechanical connection end, and the eccentric shaft 41 is connected to the cooling assembly 30 through the speed regulating gear set 60.

[0134] Specifically, the speed regulating gear set 60 includes a plurality of gears that cooperate with each other. The speed regulating gear set 60 can be designed with different transmission gear ratios to increase or decrease the speed, so as to match the motor speed with the speeds of the cooling pump 31 and the cooling fan 321 .

[0135] It can be understood that the speed regulating gear set 60 can be independently designed with a speed regulating housing, and the speed regulating housing can be fixed to the rear cover 50 by structures such as bolts or rivets, or can also be integrally formed with the rear cover 50. Then the speed regulating gear set 60 is installed in the speed regulating housing, wherein the eccentric shaft 41 penetrates the rear cover 50 and one side wall of the speed regulating housing and extends into the speed regulating housing, and is coaxial and fixedly connected with the gear shaft of the driving gear 61 of the speed regulating gear set 60, and the gear shaft of the output gear 62 of the speed regulating gear set 60 penetrates the other side wall of the speed regulating housing and is coaxial and fixedly connected with the first gear shaft 312 of the cooling pump 31, or is coaxial and fixedly connected with the gear shaft of the second gear 314, or can also be coaxial and fixedly connected with the gear shaft of the second inner gear ring 315.

[0136] Alternatively, in one embodiment, see Figure 7 The cooling pump 31 includes a pump body 311, which is fixedly arranged on the end surface of the rear cover 50 facing away from the inner stator 20; a gear cavity 311A ​​and a pump cavity 311B are sequentially defined in the pump body 311 along the direction from the inner stator 20 to the cooling assembly 30, and the pump cavity 311B is connected to the circulation channel; wherein the speed regulating gear set 60 is arranged in the gear cavity 311A.

[0137] Specifically, the pump body 311 of the cooling pump 31 is fixed to the end face of the rear cover 50 of the inner stator 20 by bolts or rivets, or can be integrally formed with the rear cover 50. Two cavities are defined in the pump body 311 along the axial direction of the inner stator 20, wherein the gear cavity 311A ​​is close to the rear cover 50, and the pump cavity 311B is far away from the rear cover 50. The pump cavity 311B is connected to the circulation channel to drive the coolant to circulate in the circulation channel. The two cavities are connected to facilitate the installation of the gear shaft of the speed regulating gear set 60 and / or the gear of the cooling pump 31. Of course, in order to prevent the lubricating oil in the gear cavity 311A ​​from contaminating the coolant in the pump cavity 311B, a sealing member such as a sealing ring can be used to seal the gear shaft across the two cavities.

[0138] In one example, see Figure 7 and Figure 8 , the speed regulating gear set 60 includes two gears, and the cooling pump 31 is an internal gear pump. At this time, the gear chamber 311A ​​includes two first sub-cavities, the central axes of the two first sub-cavities are parallel and the distance between them is less than the sum of the radius of the two, and the central axis of one of the first sub-cavities is collinear with the central axis of the inner stator 20, and the other first sub-cavity is eccentrically arranged and collinear with the central axis of the eccentric shaft 41. The eccentric shaft 41 penetrates the rear cover 50 and the pump body 311 and extends into the aforementioned other first sub-cavity. At this time, the driving gear 61 of the speed regulating gear set 60 is sleeved on the eccentric shaft 41. The output gear 62 of the speed regulating gear is installed in one of the aforementioned first sub-cavities, and its gear shaft extends into the pump to connect with the second inner gear ring 315. The first gear 313 is installed in the pump chamber 311B and sleeved on the first gear shaft 312, and the central axes of the first gear shaft 312 and the first gear 313 are both collinear with the central axis of the inner stator 20. In addition, the first gear shaft 312 passes through the pump body 311 and then continues to extend in the axial direction of the inner stator 20 in a direction away from the inner stator 20 for installing the impeller of the cooling fan 321. In this example, when the eccentric shaft 41 is eccentrically arranged, the first gear shaft 312 and the impeller shaft are returned to the central axis of the inner stator, thereby achieving a better symmetrical design of the thrust assembly.

[0139] In addition, when the motor is installed on a platform such as an aircraft and used as an electric engine, it is the power source of the electric aircraft. It is understandable that in an aircraft, during specific operation, the motor controller 70 is required to convert the input power of the onboard power supply into the power required for the motor drive, and to adjust the motor operating parameters. Therefore, in one embodiment, the motor assembly also includes a motor controller 70, which is fixedly arranged in the central shaft hole; the motor controller 70 defines a housing space that passes through the motor controller 70 along the axial direction of the inner stator 20; wherein a portion of the eccentric shaft 41 is arranged in the housing space.

[0140] Specifically, see Figure 1 and Figure 2 The rear cover 50 is configured as a U-shaped housing. The open end of the rear cover 50 is fixedly connected to the inner stator 20 through fasteners such as bolts. The U-shaped housing and the stator housing of the inner stator 20 jointly enclose a space. The motor controller 70 is installed in this space. Alternatively, the motor controller 70 extends into the central shaft hole from the side of the inner stator 20 away from the mechanical coupling end. At this time, the housing of the motor controller 70 is configured as the rear cover 50 to cover the central shaft hole. In this way, the overall weight of the electric motor can be reduced, and it is beneficial to the installation between the motor controller 70 and the inner stator 20.

[0141] The motor controller 70 includes a plurality of electronic components. In order to facilitate the passage of the eccentric shaft 41, and since the installation of the various electronic components inside the motor controller 70 can be spaced apart from each other to leave sufficient space, a receiving space extending along the axial direction of the inner stator 20 can be defined inside the motor controller 70 for placing the eccentric shaft 41.

[0142] It is not difficult to see that compared with the cooling component of the electric motor in the related art, it is difficult for the traditional independent electric drive component to meet the safety requirements of the aircraft. The electric motor provided in this embodiment drives the cooling fan and the pump in the cooling component through mechanical transmission structures such as the eccentric shaft, with higher reliability, so that the safety of the electric motor is improved.

[0143] In addition, since a large amount of heat is also generated by the power devices inside the motor controller 70 during operation, a second coolant flow channel 71 can also be defined inside the motor controller 70. The second coolant flow channel 71 is connected in series or in parallel with the first coolant flow channel 22 and then connected to the coolant heat dissipation flow channel, so that the coolant driven by the coolant pump 31 flows inside to带走 the heat generated inside the motor controller 70.

[0144] It can be understood that when the second coolant flow channel 71 is connected in series with the first coolant flow channel 22, the second coolant flow channel 71, the first coolant flow channel 22, and the coolant heat dissipation flow channel jointly form a circulation flow channel, and the coolant pump 31 drives the coolant to flow in the circulation flow channel. When the second coolant flow channel 71 is connected in parallel with the first coolant flow channel 22, the second coolant flow channel 71 and the first coolant flow channel 22 are respectively connected to the coolant heat dissipation flow channel, thus forming two circulation flow channels.

[0145] In one embodiment, when the second coolant flow channel 71 is connected in series with the first coolant flow channel 22, the first coolant flow channel 22 includes a stator base plate flow channel 221 and a winding flow channel 222 which are connected in sequence, and a first rear cover flow channel 51 is defined in the rear cover 50, one end of the first rear cover flow channel 51 is connected to the coolant inlet, and the other end of the first rear cover flow channel 51 is connected to the second coolant flow channel 71; the rear cover 50 also defines a second rear cover flow channel 52, one end of the second rear cover flow channel 52 is connected to the winding flow channel 222, and the other end of the second rear cover flow channel 52 is connected to the coolant outlet.

[0146] Specifically, see Figure 5 , the part of the stator housing of the inner stator 20 near the mechanical connection end is the stator bottom plate. The stator bottom plate defines a stator bottom plate flow channel 221. The part of the stator housing for installing the winding defines a winding flow channel. The rear cover 50 is provided with a plurality of through holes, of which the one near the center of the rear cover 50 is the coolant inlet, and the one near the edge of the rear cover 50 is the coolant outlet. A first rear cover flow channel 51 is provided in the bottom plate of the rear cover 50 (the end away from the inner stator), one end of the first rear cover flow channel 51 is connected to the coolant inlet, and the other end thereof is connected to the second coolant flow channel 71. It can be understood that the cooling pump 31 can be arranged on the first rear cover flow channel 51, so that the cooling pump 31 is integrated into the rear cover 50 and the connection relationship between the cooling pump 31 and the flow channel in the motor assembly is simpler.

[0147] At least one cooling plate is arranged in the space enclosed by the rear cover 50 and the inner stator 20, and various power devices in the motor controller 70 are mounted on the cooling plate, such as the power module of the drive motor, the power module of the drive cooling assembly 30, the DC bus capacitor, and the control module for controlling the pitch-changing assembly of the propeller, etc. An electric control board flow channel, i.e., the second coolant flow channel 71, is defined in the cooling plate.

[0148] In addition, a second rear cover flow channel 52 is also opened in the peripheral wall of the rear cover 50, and one end of the second rear cover flow channel 52 is connected to the winding flow channel 222 in the inner stator, and the other end is directly connected to the coolant outlet.

[0149] In addition, it should be noted that the winding flow channel 222 can be arranged around all windings to take away the heat generated by each winding, or each winding flow channel 222 passes through each corresponding winding along the axial direction of the inner stator 20 to facilitate the rapid removal of heat. Alternatively, the winding flow channel 222 includes a liquid cooling cavity defined in the stator shell of the inner stator 20, and the stator core and windings of the inner stator 20 are both arranged in the liquid cooling cavity. In this way, the coolant can immerse the heat-generating components of the inner stator 20 to improve the cooling effect.

[0150] In addition, in order to achieve the above-mentioned purpose, the present invention also provides a thrust assembly, including: a motor assembly and a propeller assembly, and the mechanical connection end 101 of the propeller assembly is connected to the motor assembly.

[0151] The specific structure of the motor assembly refers to the above embodiment. Since the thrust assembly adopts all the technical solutions of all the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here. In addition, due to the reduced weight, the present invention can also improve the torque density of the thrust assembly.

[0152] The propeller assembly is connected to the mechanical connection end 101 of the motor assembly, so as to rotate driven by the outer rotor 10 .

[0153] In one embodiment, the propeller assembly includes a hub, a pitch-variable motor and a connecting cable. The hub is fixedly connected to the mechanical connection end 101 of the motor assembly. An axial through hole is defined in the hub. The pitch-variable motor is arranged in the axial through hole, and the pitch-variable motor is fixedly connected to the inner stator of the motor assembly. One end of the connecting cable is connected to the pitch-variable motor, and the other end passes through the first wiring hole 103 of the motor assembly and extends into the inner stator 20 to be connected to the electronic control module.

[0154] Specifically, the electric control module is used to control the pitch-changing assembly of the propeller. In this embodiment, the pitch-changing motor is fixedly connected to the inner stator 20 in the propeller hub, so that the pitch-changing mechanism is stationary relative to the entire propeller hub and the blades, and the electric energy and control signals required for the operation of the pitch-changing motor are stably transmitted by the electric control module in the inner stator 20 through the connecting cable, which improves the stability compared with the pitch-changing slip ring solution in the related art.

[0155] In this embodiment, the control module that provides electric energy and transmits control signals to the variable pitch motor is integrated into the motor controller 70, which can facilitate the assembly of the thrust assembly, help reduce the assembly process, and improve assembly efficiency. In addition, the control module of the variable pitch motor is integrated into the motor controller of the electric engine, and through a unified control architecture, the system design is simplified and the control efficiency is improved, the development and maintenance costs are reduced, and the maintainability of the thrust assembly is improved. Of course, it is also convenient to configure the two redundantly, thereby improving safety. In addition, the control module of the variable pitch motor is arranged in the inner stator, which has a high degree of integration in a limited installation space, and the cooling component of the electric engine can also be used to obtain a better cooling effect.

[0156] Alternatively, in some embodiments, the variable pitch motor includes a first winding and a second winding, and the control module is connected to the first winding and the second winding respectively through a connecting cable. In this way, the variable pitch motor forms a dual winding structure, thereby forming a dual redundancy configuration to improve safety. At this time, since the dual winding design increases the volume of the variable pitch motor and the space in the hub is limited, in order to arrange the control module corresponding to the variable pitch motor, the control module can be arranged in the inner stator 20.

[0157] In addition, the present invention also provides an aircraft, which includes an aircraft body and at least one thrust assembly, and the thrust assembly is arranged on the aircraft body. The specific structure of the thrust assembly refers to the above embodiment. Since the present aircraft adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.

[0158] The aircraft may be a drone or an electric vertical take-off and landing aircraft eVTOL.

[0159] The above are only exemplary embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly / indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A motor assembly, characterized in that: include: An outer rotor, wherein one axial end of the outer rotor is a mechanical connection end, and the other axial end of the outer rotor is an open end; the outer rotor comprises a rotating shaft, and the outer rotor has a first wiring hole; an inner stator, at least a portion of which extends from the open end into the outer rotor and is rotatably connected to the outer rotor, and the inner stator has a central axial hole that penetrates the inner stator along the axial direction of the inner stator; the rotating shaft is rotatably connected to an end of the inner stator close to the mechanical coupling end through a bearing; A cooling assembly, the cooling assembly being arranged on a side of the inner stator away from the mechanical coupling end; An eccentric shaft, wherein a portion of the eccentric shaft is rotatably disposed in the central shaft hole around its own central axis, the central axis of the eccentric shaft is parallel to the central axis of the central shaft hole and is spaced apart from each other, and one end of the eccentric shaft is drivingly connected to the cooling assembly, and the other end of the eccentric shaft extends to the mechanical coupling end and is drivingly connected to the outer rotor, so that the outer rotor drives the cooling assembly through the eccentric shaft; A first inner gear ring, wherein the first inner gear ring is fixedly connected to an end surface of the rotating shaft close to the open end, and a central axis of the first inner gear ring is colinear with a central axis of the rotating shaft; A matching gear, wherein the matching gear is fixedly sleeved on the other end of the eccentric shaft and meshes with the first inner gear ring; A support cover, wherein the support cover is fixedly arranged at the opening of the central shaft hole near the mechanical connection end, a portion of the surface of one side end face of the support cover protrudes to form a protrusion, and the protrusion is provided with a second wiring hole that passes through the support cover along the axial direction of the inner stator to connect the first wiring hole and the central shaft hole; wherein the protrusions are located radially outside the mating gear and are spaced apart from each other.

2. The motor assembly according to claim 1, characterized in that: The outer rotor comprises: A cylindrical member with both ends of the axial direction open; A motor front cover, wherein the motor front cover is provided with a cover hole penetrating the motor front cover, the motor front cover is fixedly arranged at one axial end of the cylindrical member to form the mechanical connection end, and the other axial end of the cylindrical member is opened to form the open end; At least part of the rotating shaft is arranged in the cylindrical member and fixedly connected to the motor front cover. The rotating shaft is provided with a rotating shaft hole passing through the rotating shaft, and the rotating shaft and the motor front cover are coaxially arranged so that the rotating shaft hole is connected to the cover hole to form the first wiring hole.

3. The motor assembly according to claim 1, characterized in that: The second wiring hole has an arc-shaped cross section and partially surrounds the matching gear.

4. The motor assembly according to claim 1, characterized in that: A first coolant flow channel is defined in the inner stator; The motor assembly further includes a rear cover, which is disposed on a side of the inner stator away from the mechanical coupling end, and has a coolant inlet and a coolant outlet communicated with the first coolant flow channel; The cooling assembly comprises: A radiator assembly, the radiator assembly comprising a radiator and a cooling fan, the radiator being arranged on a side of the rear cover away from the inner stator and spaced apart from each other, and a cooling liquid heat dissipation channel in the radiator being respectively connected to the cooling liquid inlet and the cooling liquid outlet to form a circulation channel with the first cooling liquid channel; A cooling pump, the cooling pump is arranged between the radiator and the inner stator, and the cooling pump is used to drive the coolant to flow in the coolant heat dissipation channel and the first coolant channel; Wherein, the cooling pump and the cooling fan are both drivingly connected to the eccentric shaft.

5. The motor assembly according to claim 4, characterized in that: The radiator assembly further includes at least three coolant pipes, one end of each coolant pipe is fixedly connected to the radiator and communicates with the coolant heat dissipation channel, and the other end of each coolant pipe is fixedly connected to the rear cover and communicates with the coolant inlet or the coolant outlet; The coolant flowing through the radiator enters the first coolant flow channel through the coolant inlet.

6. The motor assembly according to claim 4, characterized in that: The cooling fan is located on a side of the radiator close to the inner stator and is spaced apart from the radiator, and the cooling fan comprises an impeller shaft; The cooling pump comprises a first gear shaft, and the impeller shaft is coaxial with the first gear shaft and fixedly connected to each other; Wherein, the eccentric shaft is drivingly connected to the impeller shaft or the first gear shaft; the impeller shaft and the first gear shaft are integrally formed, and the central axis of the first gear shaft is colinear with the central axis of the inner stator.

7. The motor assembly according to claim 6, characterized in that: The cooling pump is an internal gear pump, and the cooling pump further comprises a second internal gear ring and a first gear, the second internal gear ring is meshed with the first gear, and the first gear is fixedly sleeved on the first gear shaft; wherein the second internal gear ring is drivingly connected to the eccentric shaft; or The cooling pump is an external gear pump, and the cooling pump also includes a first gear and a second gear, the first gear is fixedly sleeved on the first gear shaft, and the second gear is meshed with the first gear, wherein the second gear or the first gear is drivingly connected to the eccentric shaft.

8. The motor assembly according to claim 4, characterized in that: The cooling assembly also includes: A speed regulating gear set is arranged on a side of the rear cover away from the inner stator, and the eccentric shaft is transmission-connected to the cooling assembly through the speed regulating gear set.

9. The motor assembly according to claim 8, characterized in that: The cooling pump comprises a pump body, which is arranged on the end surface of the rear cover away from the inner stator, and the pump body defines a gear cavity and a pump cavity in sequence along the direction from the inner stator to the cooling assembly, and the pump cavity is connected to the circulation channel; Wherein, the speed regulating gear set is arranged in the gear cavity.

10. The motor assembly according to claim 4, characterized in that: The motor assembly further includes a motor controller, which is disposed in the central shaft hole, and defines an accommodation space extending along the axial direction of the inner stator; Wherein, part of the eccentric shaft is arranged in the accommodating space.

11. The motor assembly according to claim 10, characterized in that: A second coolant flow channel is defined in the motor controller, and the second coolant flow channel is connected in series or in parallel with the first coolant flow channel and then communicated with the coolant heat dissipation flow channel.

12. The motor assembly according to claim 11, characterized in that: When the second coolant flow channel is connected in series with the first coolant flow channel, the first coolant flow channel includes a stator bottom plate flow channel and a winding flow channel which are connected in sequence, the stator bottom plate flow channel is connected with the second coolant flow channel, the winding flow channel includes a liquid cooling cavity defined in a stator shell of an inner stator, and the stator core and winding of the inner stator are both arranged in the liquid cooling cavity; the second coolant flow channel is configured as an electric control board flow channel; A first rear cover flow channel and a second rear cover flow channel are defined in the rear cover, one end of the first rear cover flow channel is connected to the coolant inlet, and the other end of the first rear cover flow channel is connected to the second coolant flow channel; one end of the second rear cover flow channel is connected to the winding flow channel, and the other end of the second rear cover flow channel is connected to the coolant outlet.

13. A thrust assembly, characterized in that: include: The motor assembly according to any one of claims 1 to 12; as well as A propeller assembly is connected to the mechanical connection end of the motor assembly.

14. The thrust assembly according to claim 13, wherein: The propeller assembly comprises: A propeller hub, the propeller hub is fixedly connected to the mechanical coupling end, and an axial through hole is defined in the propeller hub; A variable pitch motor, the variable pitch motor is disposed in the axial through hole, and the variable pitch motor is fixedly connected to the inner stator of the motor assembly; and A connecting cable, one end of which is connected to the variable pitch motor, and the other end of which passes through the first wiring hole of the motor assembly and extends into the inner stator to be connected to the control module.

15. An aircraft, characterized in that: The aircraft comprises: Aircraft airframe; and At least one thrust assembly according to claim 13 or 14, arranged on the aircraft body.

16. The aircraft according to claim 15, characterized in that The aircraft is an electric vertical take-off and landing aircraft.

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