Electric motors, electric propulsion systems and aircraft

Abstract

This application provides an electric motor, an electric propulsion device, and an aircraft. The electric motor includes: a stator having a cavity; a rotor rotatably connected to the stator via a shaft; and the rotor being insulated from the stator; a conductive component disposed within the cavity, one end of the conductive component being conductively connected to the shaft, and the other end extending to the outside of the electric motor. The electric motor of this application, by incorporating the conductive component, creates a complete low-impedance electrical path between the shaft and the conductive component, allowing current that might be input into the electric motor via the rotor hub to be output to the outside of the electric motor, thus improving the electrical protection performance of the electric motor.

Description

Technical Field

[0001] This application relates to the field of aircraft technology, and in particular to an electric motor, an electric propulsion device, and an aircraft. Background Technology

[0002] Electric vertical take-off and landing (eVTOL) aircraft are aircraft that use electricity as their flight power source and have vertical take-off and landing capabilities. They are characterized by vertical take-off and landing, intelligent operation, low noise, low emissions, easy maintenance, and high safety.

[0003] Electric propulsion systems provide lift or thrust for electric vertical takeoff and landing (EVTOL) aircraft, including electric motors and propellers. During flight, these aircraft are susceptible to lightning strikes or static electricity generated by friction between the propeller blades and the air. These lightning strikes and static electricity can affect the stability of the electric motor. Related technologies employ carbon brushes or slip rings between the rotor and stator of the electric motor to guide the current from lightning strikes or static electricity.

[0004] However, the aforementioned lightning and electrostatic protection methods can easily affect electric motors and their internal motor controllers, requiring frequent maintenance and offering poor protection. Utility Model Content

[0005] This application provides an electric motor, an electric propulsion device, and an aircraft. By setting conductive components, the rotor hub, shaft, and conductive components form a complete low-impedance electrical path, which outputs the current that may be input into the electric motor through the rotor hub to the outside of the electric motor, thereby improving the lightning and electrostatic protection performance of the electric motor.

[0006] In a first aspect, embodiments of this application provide an electric motor, comprising: a stator having a cavity; a rotor rotatably connected to the stator via a rotating shaft; wherein the rotor is insulated from the stator; and a conductive component disposed within the cavity, one end of the conductive component being conductively connected to the rotating shaft, and the other end extending to the outside of the electric motor.

[0007] The electric motor of this invention features a conductive component within the stator that is electrically connected to the rotating shaft. Lightning, static electricity, and other electrical disturbances that may be conducted to the electric motor from the rotor hub are transmitted to the outside of the motor via the rotating shaft and the conductive component. This creates a low-impedance electrical path through the electric motor's interior, optimizing the transmission path of potential currents and improving the motor's lightning and static electricity protection capabilities. This, in turn, extends the motor's lifespan and reduces user operating costs.

[0008] In some embodiments, the rotor is rotatably sleeved on the outside of the stator, a portion of the shaft extends into the cavity, and a bearing is disposed between the shaft and the stator. The bearing includes an inner ring, an outer ring, and rolling elements rotatably disposed between the inner and outer rings. The inner ring is connected to the shaft, and the outer ring is connected to the stator. The connection between the shaft and the inner ring is insulated; and / or, the rolling elements are insulated; and / or, the connection between the outer ring and the stator is insulated; and / or, the opposing surfaces of the rotor and the stator are insulated.

[0009] In some embodiments, the conductive component includes a first conductive rail and a second conductive rail, at least a portion of the structure of the first conductive rail is located within the cavity, the first conductive rail is connected to the rotating shaft, and the second conductive rail is located at the end of the first conductive rail extending away from the rotor along the central axis of the rotor, and the second conductive rail is electrically connected to the first conductive rail.

[0010] According to some embodiments of the present invention, the first conductive rail has a first end and a second end extending along the central axis of the rotor. The first end is connected to the rotating shaft, and at least a portion of the structure of the second end is conductively connected to the second conductive rail. A conductive end face is provided at one end of the second conductive rail facing the first conductive rail, and at least a portion of the surface of the second end is conductively connected to the conductive end face.

[0011] According to some embodiments of the present invention, a portion of the structure at one end of the second conductive rail facing the first conductive rail is recessed away from the first conductive rail to form a first cavity, at least a portion of the structure at the second end extends into the first cavity, and the inner wall of the first cavity constitutes the conductive end face; and / or, in the direction extending away from the first conductive rail along the central axis of the rotor, the diameter of the first cavity gradually decreases, and in the direction extending toward the first cavity along the central axis of the rotor, the diameter of the second end gradually decreases, and the peripheral wall of the second end is electrically connected to the conductive end face.

[0012] According to some embodiments of the present invention, a conductive gap is provided between the conductive end face and at least a portion of the surface of the second end, and conductive grease is provided in the conductive gap; or, a conductive rolling element is provided between the conductive end face and at least a portion of the surface of the second end, and conductive grease is coated between the conductive rolling element and at least a portion of the surface of the conductive end face and the second end.

[0013] According to some embodiments of the present invention, the conductive component further includes a conductive wire and an electromagnetic shielding sleeve. One end of the conductive wire is fixedly connected to the second conductive rail, and the other end extends to the outside of the electric motor. The electromagnetic shielding sleeve is fitted over the conductive wire.

[0014] According to some embodiments of the present invention, the conductive component further includes a guide rail seat and an elastic element. The guide rail seat is fixedly disposed within the stator and is located on the side of the second conductive rail away from the first conductive rail. The second conductive rail is mounted on the guide rail seat and is insulated from the guide rail seat. The elastic element is disposed between the second conductive rail and the guide rail seat and is used to apply an elastic force to the second conductive rail so that the second conductive rail tends to move toward the first conductive rail.

[0015] According to some embodiments of the present invention, a portion of the structure of the second conductive rail facing the guide rail seat is recessed away from the guide rail seat to form a second cavity; a portion of the structure of the guide rail seat protrudes towards the second conductive rail to form a mounting protrusion, the mounting protrusion extending into the second cavity so that the second conductive rail is mounted on the guide rail seat; and / or, the guide rail seat has a seat through hole extending along the extension direction of the rotor central axis, and the conductive wire passes through the seat through hole.

[0016] In some embodiments, the device further includes: a motor controller and a motor rear cover, the motor rear cover being disposed on one end of the cavity opposite to the rotor, and the motor controller being disposed within the cavity of the stator; the motor controller includes a controller mounting plate having a controller through hole, the conductive component passing through the controller through hole and leading to the outside of the electric motor; and / or, the motor rear cover having a motor rear cover through hole, the conductive component passing through the motor rear cover through hole and leading to the outside of the electric motor.

[0017] According to some embodiments of the present invention, the motor controller includes a first type of electronic component and a second type of electronic component, wherein the electromagnetic sensitivity of the first type of electronic component is lower than that of the second type of electronic component.

[0018] The distance between the first type of electronic component and the through hole of the controller is less than the distance between the second type of electronic component and the through hole of the controller.

[0019] Secondly, embodiments of this application also provide an electric propulsion device, comprising: a blade; a hub electrically connected to the blade; and the aforementioned electric motor, wherein the rotor of the electric motor is electrically connected to the hub.

[0020] In some embodiments, the electric propulsion device further includes: a pitch control mechanism connected to the blade root and the blade hub; the connection between the pitch control mechanism and the blade root is insulated, and the connection between the pitch control mechanism and the blade hub is insulated.

[0021] Thirdly, embodiments of this application also provide an aircraft, comprising: an airframe; an external skin covering the airframe, the skin being a conductive component; the aforementioned electric motor, the electric motor being located inside the airframe; or the aforementioned electric propulsion device, the electric motor of the electric propulsion device being located inside the airframe, the conductive component of the electric motor being conductively connected to the skin.

[0022] This application provides an electric motor, electric propulsion device, and aircraft that forms a dedicated low-impedance path by directly connecting conductive components to the rotor shaft and diverting the current to the outside of the electric motor. Simultaneously, insulation is provided between the rotor and stator to prevent the risk of current directly penetrating the stator. This low-impedance path effectively diverts current generated by lightning or static electricity, preventing random discharge between the rotor and stator, thereby protecting the core components of the electric motor from damage and improving protection against lightning strikes and static electricity.

[0023] Under the planned lightning and static electricity path, lightning and static electricity are only conducted along this path, preventing lightning from randomly entering the electric motor and causing performance degradation or direct failure. It also prevents lightning and static electricity from directly conducting lightning current into the motor from the power and signal lines at the motor end, thus avoiding safety threats to other electrical equipment. The lightning and static electricity current will not flow on the stator, and the electromagnetic field generated during the flow of lightning and static electricity will not affect the motor windings. The insulation treatment at the low-impedance path and small gaps also minimizes the possibility of breakdown and conduction through these gaps. Attached Figure Description

[0024] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0025] Figure 1 This is a schematic diagram of the structure of the aircraft according to an embodiment of this application;

[0026] Figure 2 This is one of the schematic diagrams of the assembly structure of the propeller and the electric motor according to an embodiment of this application;

[0027] Figure 3 This is a schematic diagram of the pitch-changing structure on the electric motor according to an embodiment of this application;

[0028] Figure 4This is a second schematic diagram of the assembly structure of the propeller and the electric motor according to an embodiment of this application;

[0029] Figure 5 This is a schematic diagram of the structure of the conductive component according to an embodiment of this application;

[0030] Figure 6 This is a partial structural schematic diagram of the electric motor according to an embodiment of this application;

[0031] Figure 7 This is a schematic diagram of the structure of the motor controller according to an embodiment of this application.

[0032] Figure label:

[0033] 10 - Aircraft;

[0034] 11-Fuselage; 12-Wing; 13-Tail; 14-Arm; 15-Nacelle;

[0035] 100-Electric motor;

[0036] 101-Stator;

[0037] 102 - Rotor; 1021 - Shaft;

[0038] 103-Conductive component; 1031-First conductive rail; 1031a-First end; 1031b-Second end; 1032-Second conductive rail; 1032a-Conductive end face; 1032c-Second cavity; 1033-Conductive wire; 1034-Electromagnetic shielding sleeve; 1035-Guide rail base; 1035a-Mounting protrusion; 1036-Elastic element;

[0039] 104 - Bearing; 1041 - Bearing inner ring; 1042 - Bearing outer ring; 1043 - Bearing rolling element;

[0040] 105 - Motor controller; 1052 - Category I electronic components; 1053 - Category II electronic components;

[0041] 200-blade;

[0042] 300-propeller hub;

[0043] 400-Variable pitch mechanism.

[0044] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0045] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0046] Electric vertical takeoff and landing (EVTOL) aircraft (hereinafter referred to as aircraft) include an electric motor. The electric motor provides power to the aircraft. During flight, the aircraft is susceptible to lightning strikes or static electricity generated by friction between the aircraft's propeller blades. These lightning strikes and static electricity can affect the operational stability of the electric motor. In related technologies, carbon brushes or slip rings are installed between the rotor and stator of the electric motor to guide the current from lightning strikes or static electricity.

[0047] Specifically, the conductive slip ring is installed on the rotor shaft, the carbon brush assembly is fixed on the stator side, and the carbon brush is connected to the aircraft fuselage grounding network through wires, ultimately guiding the current into the airborne lightning protection system or directly discharging it into the atmosphere.

[0048] Designs that guide lightning or electrostatic current by using carbon brushes or slip rings on electric motors have significant protective defects. The main problems stem from the dynamic instability of the mechanical contact structure, insufficient high current carrying capacity, poor environmental adaptability, and the tendency to divert current to the stator. Specifically, poor dynamic contact between the carbon brush and slip ring is a problem. The carbon brush maintains contact with the rotating slip ring through spring pressure, but during use, the carbon brush is prone to radial oscillation, leading to fluctuations in contact resistance. Increased contact resistance can cause localized high temperatures during a lightning strike, even melting the contact surface and causing the conductive path to fail, resulting in protection failure. Since the stator and rotor are connected by bearings, when the carbon brush and slip ring fail, current will be conducted to the stator through the bearings, damaging stator components. Furthermore, lightning strikes can instantly damage the conductivity of the carbon brush or slip ring. The friction between the carbon brush and slip ring generates carbon dust, which, when accumulated, can cause short circuits or arcing, also easily leading to protection failure. Ultimately, this will cause current to be guided to the stator, damaging stator components. Moreover, the need for regular maintenance, cleaning, or replacement of the carbon brush and slip ring, including the regular removal of carbon dust, necessitates frequent maintenance. Additionally, carbon brushes and slip rings are only suitable for low-speed motors; high-speed motors will damage the conductivity of the carbon brushes or slip rings.

[0049] Therefore, although carbon brushes and slip rings can guide current between the rotor and stator of an electric motor, these methods are prone to affecting the motor due to the aforementioned reasons. This not only necessitates frequent maintenance but also increases the risk of current conduction failure. When current conduction fails, lightning and electrostatic currents from the blades will flow sequentially through the hub, rotor, and bearings to the stator. This current will then affect the stator windings and the motor controller, ultimately damaging the entire electric motor. Therefore, the aforementioned lightning and electrostatic protection methods are susceptible to impacting the electric motor and its internal controller, requiring frequent maintenance and offering only limited protection.

[0050] In view of this, embodiments of this application provide an electric motor, an electric propulsion device, and an aircraft. By setting conductive components, the rotor hub, the shaft, and the conductive components form a complete low-impedance electrical path, which outputs the current that may be input into the electric motor through the rotor hub to the outside of the electric motor, thereby improving the electrical protection performance of the electric motor.

[0051] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0052] refer to Figures 1 to 7 In a first aspect, embodiments of this application provide an electric motor 100, which may include a stator 101, a rotor 102, and a conductive component 103.

[0053] refer to Figure 3 , Figure 4 , Figure 5 and Figure 6 The stator 101 has a cavity, and the rotor 102 is provided with a rotating shaft 1021. The rotor 102 is rotatably connected to the stator 101 through the rotating shaft 1021. Exemplarily, the rotating shaft 1021 can be fixedly connected or rotatably connected to the rotor 102. The rotating shaft 1021 can extend into the cavity, and the part of the rotating shaft 1021 inside the cavity is rotatably connected to the stator 101 through a bearing 104.

[0054] The rotor 102 is rotatably connected to the stator 101 via a rotating shaft 1021. Alternatively, the rotating shaft 1021 can be connected to both the stator 101 and the rotor 102, in which case the rotor 102 and the rotating shaft 1021 can be separate components. Alternatively, the rotating shaft 1021 can be fixedly connected to the rotor 102 and then rotatably engaged with the stator 101. In this case, the rotating shaft 1021 and the rotor 102 can be integrally formed, or they can be separately formed and then fixedly connected by welding or bolts.

[0055] Optionally, the rotating shaft 1021 can be coaxially arranged with the central shaft hole of the stator 101. The stator 101 has an internal cavity, and the central shaft hole of the stator 101 can pass through the end of the stator 101 facing the rotor 102 and communicate with the cavity. In this case, the central shaft hole can be located on the end face of the stator 101 facing the rotor 102, and the bearing 104 can be located inside the central shaft hole, so that the rotor 102 and the stator 101 are rotatably connected. Alternatively, the cavity of the stator 101 can directly form the central shaft hole. In this case, the stator 101 includes a stator support, and the bearing 104 is installed between the stator support and the rotating shaft 1021, so that the stator 101 and the rotor 102 are rotatably connected. Of course, in other embodiments of this application, the rotating shaft 1021 can also be located at other positions of the stator 101, and this application does not limit this.

[0056] Understandably, in this application, the pivot 1021 can be a hollow shaft structure. In this case, the pivot 1021 can be connected to the cavity, which is beneficial for saving materials, improving the lightweight effect of the aircraft 10, and extending the endurance of the aircraft 10. Alternatively, the pivot can also be a solid shaft structure to ensure that the pivot 1021 has sufficient structural strength and improve the structural reliability of the electric motor 100.

[0057] The rotor 102 can be connected to the hub 300 of the electric propulsion device. For example, the rotor 102 may have a mounting hole extending along its central axis. The hub 300 can be fixedly mounted in the mounting hole by interference fit or key connection. Alternatively, a flange can be provided on the end face of the hub 300 facing the rotor 102, and the flange can be fixedly connected to the rotor 102 by bolts. This allows the rotor 102 to be directly connected to the load without the need for additional couplings or transmission components to connect the rotor 102 to the hub 300, making the overall structure of the electric motor 100 more compact.

[0058] Furthermore, in order to improve the electrical safety of the electric motor 100, the hub 300 and the rotor 102 can be insulated from each other, for example, by spraying an insulating coating on the surface of the hub 300 that contacts the rotor 102.

[0059] Insulation is provided between the rotor 102 and the stator 101. For example, a bearing 104 may be provided between the rotor 102 and the stator 101. The bearing 104 may be an insulated bearing 104. Alternatively, an insulating coating may be provided on the surface of the rotor 102 facing the stator 101. Or, an insulating coating may be provided on the surface of the stator 101 facing the rotor 102. This is to prevent high voltage from breaking down the small gap between the stator 101 and the rotor 102, forming a plasma discharge channel, and generating arc heat or Joule heat, which would demagnetize the magnets in the electric motor, burn out the windings, and cause the electric motor 100 to fail.

[0060] The rotating shaft 1021 can be electrically connected to the propeller hub 300. For example, the rotating shaft 1021 can be fixedly installed in the mounting hole on the rotor 102 by snap-fit ​​or key connection. Part of the structure of the rotating shaft 1021 extends toward the propeller hub 300 and contacts the propeller hub 300 to form a conductive connection. At the same time, the part of the rotating shaft 1021 facing the stator 101 extends to the inside of the stator 101 and is electrically connected to the conductive component 103 to form a complete conductive path.

[0061] The conductive component 103 is located within the cavity. One end of the conductive component 103 is electrically connected to the rotating shaft 1021, and the other end extends to the outside of the electric motor 100. Exemplarily, at the end of the conductive component 103 facing the rotating shaft 1021, during rotation of the rotating shaft 1021, at least a portion of the conductive component 103 maintains a conductive connection with the rotating shaft 1021. For example, the conductive component 103 may have an end face that slides against the end face of the rotating shaft 1021 facing the stator 101. Alternatively, either the conductive component 103 or the rotating shaft 1021 may have an encapsulating structure that encapsulates the other, ensuring sufficient conductive contact between the conductive component 103 and the rotating shaft 1021 during rotation, thereby improving the reliability of the conductive effect. Alternatively, the conductive component 103 may have two rotating contact parts (such as the first conductive rail 1031 and the second conductive rail 1032 described below), one part (the first conductive rail 1031) being fixed relative to the rotating shaft 1021 and rotating with the rotating shaft 1021 to achieve a rotating conductive connection between the conductive component 103 and the rotating shaft 1021. Alternatively, the conductive component 103 may also have multiple rolling conductive elements arranged around the axis of the rotating shaft 1021. As the rotating shaft 1021 rotates with the rotor 102, the rolling conductive elements roll and abut against the rotating shaft 1021, forming a stable current conduction channel. At the same time, this helps to reduce wear on the contact parts between the conductive component 103 and the rotating shaft 1021, thereby extending the service life of the equipment.

[0062] The other end of the conductive component 103 may have a current-guiding structure such as a conductive wire, which extends to the outside of the electric motor 100 to achieve the current-guiding effect.

[0063] The electric motor 100 of this invention is electrically connected to the rotating shaft 1021 via a rotor hub 300, and a conductive component 103 disposed within the stator 101 is also electrically connected to the rotating shaft 1021. Lightning, static electricity, etc., that may be conducted from the rotor hub 300 to the electric motor 100 are transmitted to the outside of the electric motor 100 via the rotating shaft 1021 and the conductive component 103. Compared to traditional carbon brush or slip ring designs, the electric motor 100 of this invention forms a low-impedance electrical path through the interior of the electric motor 100, optimizing the transmission path of current that may enter the electric motor 100. Lightning is only conducted along this path, preventing disorderly lightning strikes from entering the electric motor 100 and causing performance degradation or direct failure. It also prevents lightning and static electricity from directly introducing lightning current into the motor from the power and signal lines, thus avoiding safety threats to more electrical equipment.

[0064] In this way, lightning and electrostatic current will not flow on the stator 101, and the electromagnetic field generated during the lightning electrostatic flow will not affect the windings on the stator 101. The low-impedance path formed and the insulation treatment between the stator 101 and the rotor 102 also help prevent lightning from breaking down and conducting to the stator 101 through the small gap. This improves the lightning and electrostatic protection capability of the electric motor 100, thereby extending the service life of the electric motor 100 and reducing the user's operating costs. At the same time, it also reduces the wear of the electric motor 100, thereby reducing the maintenance frequency and cost.

[0065] refer to Figure 3 , Figure 4 , Figure 5 and Figure 6 In some embodiments, the rotor 102 is rotatably sleeved on the outside of the stator 101, and the rotor 102 is fixedly connected to the shaft 1021. Exemplarily, the rotor 102 and the shaft 1021 are integrally formed, or the rotor 102 and the shaft 1021 are separately formed and then fixedly connected by welding or bolts. In this case, the electric motor 100 is configured as an external rotor motor. Compared to the structure of an internal rotor motor, the integrated structure of the stator 101, rotor 102, and controller is more compact, saves installation space, and increases power density. For the aircraft 10, this not only reduces the axial and radial space occupied by the power system but also improves the overall efficiency of the power system.

[0066] A portion of the structure of the rotating shaft 1021 extends into the cavity. A bearing 104 is disposed between the rotating shaft 1021 and the stator 101. The bearing 104 may include an inner bearing ring 1041, an outer bearing ring 1042, and a rolling element 1043. The rolling element 1043 is rotatably disposed between the inner bearing ring 1041 and the outer bearing ring 1042. The inner bearing ring 1041 is connected to the rotating shaft 1021, and the outer bearing ring 1042 is connected to the stator 101. Exemplarily, the inner bearing ring 1041 may be fitted onto the outside of the rotating shaft 1021, and the outer bearing ring 1042 may be fitted onto the inside of the stator 101. Here, the inner bearing ring 1041 is connected to the rotating shaft 1021, and the outer bearing ring 1042 is connected to the stator 101. This application does not limit the connection method in which the inner bearing ring 1041 is connected to the rotating shaft 1021, and the outer bearing ring 1042 is connected to the stator 101.

[0067] Insulation is provided at the connection between the shaft 1021 and the inner ring 1041 of the bearing. For example, the outer side of the shaft 1021 may be covered with an insulating spray material at the connection between the shaft 1021 and the inner ring 1041 of the bearing, or an insulating bushing may be provided at the connection between the shaft 1021 and the inner ring 1041 of the bearing.

[0068] The bearing rolling element 1043 can be an insulating element. For example, the bearing rolling element 1043 can be made of ceramic insulating material or other insulating material.

[0069] The connection between the bearing outer ring 1042 and the stator 101 can be insulated. For example, an insulating spray material can be provided on the outside of the bearing outer ring 1042 at the connection between the bearing outer ring 1042 and the stator 101, or an insulating bushing can be provided between the bearing outer ring 1042 and the stator 101.

[0070] In the above embodiments, insulation is provided at the connection between the rotating shaft 1021 and the inner ring 1041 of the bearing, and between the outer ring 1042 of the bearing and the stator 101 (such as providing an insulating layer, insulating spray material, and insulating bushing, etc.). This can effectively block the current generated by lightning or static electricity from forming an unexpected conductive path through the bearing 104, forcing the current to be directed out only through the designed conductive path, and avoiding the situation where the bearing 104 is corroded due to static electricity.

[0071] It is understood that in this application, the electric motor 100 may simultaneously have three conditions: insulation at the connection between the shaft 1021 and the inner ring 1041 of the bearing, the bearing rolling element 1043 being configured as an insulating element, and insulation at the connection between the outer ring 1042 of the bearing and the stator 101. Of course, in other embodiments of this application, the electric motor 100 may also have one or more of the above three conditions, and this application does not impose any limitations on this.

[0072] The opposing surfaces of the rotor 102 and the stator 101 can be insulated. For example, at least one of the rotor 102 or the stator 101 may be coated with an insulating coating on the surface facing the other, or an insulating separator may be provided between the rotor 102 and the stator 101, or at least one of the rotor 102 or the stator 101 may be provided with an insulating layer to prevent high voltage from breaking down the small gap between the stator 101 and the rotor 102, forming a plasma discharge channel, and generating arc heat or Joule heat, which could demagnetize the magnets in the electric motor, burn out the windings, and cause the electric motor 100 to fail.

[0073] According to some embodiments of the present invention, the conductive component 103 may include a first conductive rail 1031 and a second conductive rail 1032. At least a portion of the first conductive rail 1031 is located within the cavity. For example, the first conductive rail 1031 may be partially located within the cavity, partially located outside the cavity, or the first conductive rail 1031 may be completely located within the cavity.

[0074] The first conductive rail 1031 is connected to the rotating shaft 1021. The first conductive rail 1031 can be welded to the rotating shaft 1021, or the first conductive rail 1031 can be fixed to the rotating shaft 1021 by fasteners such as bolts; or the first conductive rail 1031 and the rotating shaft 1021 can be integrally set.

[0075] The second conductive rail 1032 is located at the end of the first conductive rail 1031 extending away from the rotor 102 along the central axis of the rotor 102. The second conductive rail 1032 is electrically connected to the first conductive rail 1031. For example, the second conductive rail 1032 and the first conductive rail 1031 may have contact end faces. During the rotation of the shaft 1021 with the rotor 102, the two contact end faces slide relative to each other. During the sliding process, a portion of the two contact end faces is always in contact with each other to conduct current. The contact end faces can be flat or inclined. Alternatively, at least one of the second conductive rail 1032 and the first conductive rail 1031 may have a conductive protrusion, and the other may have a mating groove that engages with the conductive protrusion. The conductive protrusion slides along the mating groove, and a portion of the conductive protrusion is always in contact with the mating groove during the rotation of the shaft 1021 with the rotor 102. Alternatively, conductive grease may be provided between the conductive protrusion and the mating groove to improve the conductivity between the first conductive rail 1031 and the second conductive rail 1032. Alternatively, a rolling conductive element can be provided between the second conductive rail 1032 and the first conductive rail 1031. That is, during the rotation of the first conductive rail 1031 with the rotating shaft 1021, part of the structure of the rolling conductive element contacts the first conductive rail 1031, and part of the structure contacts the second conductive rail 1032, forming a complete current path. The rolling conductive element can be fixedly connected to the first conductive rail 1031 and in rolling contact with the second conductive rail 1032; alternatively, it can be fixedly connected to the second conductive rail 1032 and in rolling contact with the first conductive rail 1031; or it can simultaneously be in rolling contact with both the first and second conductive rails 1031. In this case, one of the first or second conductive rails 1031 can be provided with a recess (such as a rolling groove as described later) for accommodating the rolling conductive element.

[0076] In this embodiment, the second conductive rail 1032 is used to lead the current transmitted by the propeller hub 300 to the outside of the electric motor 100. For example, the second conductive rail 1032 may be connected to a conductive wire 1033 extending out of the outside of the electric motor 100, or a part of the structure of the second conductive rail 1032 may extend out of the electric motor 100 to conduct lightning, static electricity and other currents inside the electric motor 100 to the outside of the electric motor 100.

[0077] It should be noted that when part of the structure of the second conductive rail 1032 extends out of the electric motor 100, the extended part of the second conductive rail 1032 needs to be insulated to avoid damage to the internal components of the electric motor 100.

[0078] Optionally, in order to further improve the protection effect on the internal components of the electric motor 100, the conductive component 103 and the stator 101 can be insulated from each other. For example, the surfaces of each component of the conductive component 103 facing the inner wall of the stator 101 can be coated with an insulating coating, or an insulating material (such as a rubber gasket) can be provided between the conductive component 103 and the stator 101.

[0079] In this way, lightning, static electricity, etc. that may be conducted on the rotor hub 300 to the electric motor 100 are transmitted through the shaft 1021 and the first conductive rail 1031 of the conductive component 103 to the second conductive rail 1032 of the conductive component 103, and the current is transmitted to the outside of the electric motor 100 through the second conductive rail 1032.

[0080] refer to Figure 4 and Figure 5 In some embodiments, the first conductive rail 1031 has a first end 1031a and a second end 1031b extending along the central axis of the rotor 102. The first end 1031a is connected to the rotating shaft 1021. Exemplarily, the first end 1031a can be fixed to the rotating shaft 1021 by welding, or the end face of the rotating shaft 1021 facing the first end 1031a can be provided with a flange, and the flange can be fixedly connected to the first end 1031a by fasteners such as bolts, so that current can be stably transmitted from the rotating shaft 1021 to the first conductive rail 1031, improving the conductivity reliability between the rotating shaft 1021 and the first conductive rail 1031. Of course, in other embodiments, the first end 1031a can also be an integral structure with the rotating shaft 1021.

[0081] The second conductive rail 1032 has a conductive end face 1032a at one end facing the first conductive rail 1031. At least a portion of the surface of the second end 1031b is conductively connected to the conductive end face 1032a. The conductive end face 1032a can be the end face of the second conductive rail 1032 facing the first conductive rail 1031, and the end face of the second end 1031b facing the second conductive rail 1032 can slide against the conductive end face 1032a. The conductive end face 1032a can be a plane, or it can be a concave surface (or a convex surface) that is recessed away from the direction of the second end 1031b. Correspondingly, the second end 1031b can convex (or be recessed) towards the second conductive rail 1032 to improve the conductive stability between the second end 1031b and the second conductive rail 1032. In this way, a complete current path is formed between the first conductive rail 1031 and the second conductive rail 1032, which helps to avoid unstable current conduction caused by mechanical vibration or the rotation of the rotor 102.

[0082] Compared to the traditional conductive method that uses carbon brushes and high-current conductive slip rings, the conductive component 103 of this application uses a conductive connection between the first conductive rail 1031 and the second conductive rail 1032 for current conduction. It only needs to be inspected and maintained together with the motor when it is struck by lightning. There is no need to perform specific testing, inspection and maintenance on the carbon brushes and high-current conductive slip rings, which helps to reduce the maintenance cost of the aircraft 10.

[0083] Continue to refer to Figure 5 According to some embodiments of the present invention, the portion of the structure of the second conductive rail 1032 facing the first conductive rail 1031 is recessed away from the first conductive rail 1031 to form a first cavity. The first cavity can be a cylindrical cavity or a conical cavity. The inner wall of the first cavity forms a conductive end face 1032a, which increases the contact area between the second conductive rail 1032 and the second end 1031b and improves the conductivity stability of the conductive component 103.

[0084] At least a portion of the structure of the second end 1031b extends into the first cavity and is electrically connected with the inner wall of the first cavity. Alternatively, a portion of the structure of the second end 1031b may extend into the first cavity, or the second end 1031b may be directly inserted into the first cavity and electrically connected with the inner wall of the first cavity.

[0085] According to some embodiments of the present invention, the diameter of the first cavity gradually decreases in the direction away from the first conductive rail 1031 along the extension direction of the central axis of the rotor 102, thus forming a tapered cavity with a gradually decreasing diameter along the extension direction of the central axis.

[0086] In the direction extending along the central axis of rotor 102 toward the first cavity, the diameter of the second end 1031b gradually decreases. The peripheral wall of the second end 1031b is electrically connected to the conductive end face 1032a. Thus, the second end 1031b forms a tapered cylinder with a gradually decreasing diameter along the central axis. While increasing the contact area between the second end 1031b and the second conductive rail 1032, the second conductive rail 1032 also limits the radial and axial displacement of the first conductive rail 1031, improving the connection stability between the second end 1031b and the second conductive rail 1032. This avoids connection failure between the second end 1031b and the second conductive rail 1032 due to vibration of the electric motor 100 or rotation of the shaft 1021, which is beneficial to improving the structural reliability of the conductive component 103.

[0087] According to some embodiments of this utility model, a conductive gap is provided between at least a portion of the surfaces of the conductive end face 1032a and the second end 1031b, and conductive grease is disposed within the conductive gap. Thus, the conductive grease (such as a highly conductive grease containing copper powder or silver powder) can fill the conductive gap, forming a continuous conductive path to ensure stable current transmission between the contact surfaces, while also avoiding frictional losses caused by rigid contact. Simultaneously, the grease can reduce the contact resistance of the contact surfaces, reducing energy loss during current transmission, making it particularly suitable for scenarios involving instantaneous high currents from lightning or continuous static discharge, ensuring that the current is discharged to the outside of the electric motor 100. Furthermore, when the conductive component 103 is in a long-term operating state, partial wear may occur on the second end 1031b of the first conductive rail 1031 and the conductive end face 1032a of the second conductive rail 1032. The conductive grease can also discharge the generated debris from the contact surface, thereby extending the service life of the conductive component 103.

[0088] The conductive gap can be a micro-gap structure, allowing the first conductive rail 1031 and the second conductive rail 1032 to form a small gap that partially contacts or nearly contacts each other. In other words, the distance between the conductive mating portions of the conductive end face 1032a and the second end 1031b is sufficiently small to reduce the direct mechanical contact area between the first conductive rail 1031 and the second conductive rail 1032, thereby reducing friction and extending the service life of the conductive component 103. For example, the conductive gap D between the conductive mating portions of the conductive end face 1032a and the second end 1031b can satisfy: D = 0.1 ± 0.02 mm.

[0089] Compared to traditional carbon brushes and slip rings for conductivity, the design in this embodiment, which allows for sliding contact between the first conductive rail 1031 and the second conductive rail 1032 with a micro-gap and fills the gap with conductive grease, helps to extend the maintenance cycle of the conductive component 103, thereby extending the service life of the electric motor 100.

[0090] Alternatively, in some embodiments, the conductive end face 1032a may also slide in contact with at least a portion of the surface of the second end 1031b to ensure good conductivity between the first conductive rail 1031 and the second conductive rail 1032.

[0091] Alternatively, a conductive rolling element may be provided between at least a portion of the surfaces of the conductive end face 1032a and the second end 1031b, and conductive grease may be applied between the conductive rolling element and at least a portion of the surfaces of the conductive end face 1032a and the second end 1031b.

[0092] In the above embodiments, the conductive rolling element can be a ball or a roller, preferably a ball. A rolling groove adapted to the conductive rolling element can be provided on one of the second end 1031b or the conductive end face 1032a of the first conductive rail 1031. The conductive rolling element rolls within the rolling groove, which can limit the rolling path of the conductive rolling element and improve stability.

[0093] By using conductive rolling elements, such as balls or rollers, rolling contact is achieved between the second end 1031b and the conductive end face 1032a, replacing the sliding contact of traditional carbon brushes or slip rings, significantly reducing friction loss and wear, and lowering the maintenance frequency.

[0094] The rolling conductive element, the first conductive rail 1031, and the second conductive rail 1032 can all be made of conductive metal or other conductive materials. Optionally, multiple conductive rolling elements can be provided, all disposed within a rolling groove. The first conductive rail 1031, the conductive rolling elements, and the second conductive rail 1032 form a low-impedance electrical path through rolling contact. The multiple conductive rolling elements also make this low-impedance electrical path more reliable and shunt the current. This shunt effect prevents the conductive rolling element from burning out or failing due to excessive current on a single element.

[0095] refer to Figure 4 and Figure 5 According to some embodiments of the present invention, the conductive component 103 may further include a conductive wire 1033 and an electromagnetic shielding sleeve 1034. One end of the conductive wire 1033 is fixedly connected to the second conductive rail 1032. For example, one end of the conductive wire 1033 may be provided with a connecting ear, and the connecting ear is provided with a fixing hole. The connecting ear is attached to the surface of the second conductive rail 1032, and the conductive wire 1033 is fixedly connected to the second conductive rail 1032 by fasteners such as screws passing through the fixing hole.

[0096] The other end of the conductive wire 1033 extends to the outside of the electric motor 100. The conductive wire 1033 enables the second conductive rail 1032 to form a direct and reliable current transmission path with the outside of the electric motor 100. This ensures that the lightning and electrostatic current conducted by the rotor hub 300 through the shaft 1021, the first conductive rail 1031, and the second conductive rail 1032 can be efficiently conducted to the outside of the engine (such as the skin on the fuselage of the aircraft 10) via the conductive wire 1033. This makes the rotor hub 300 and the fuselage of the aircraft 10 have the same potential, so as to avoid the formation of a potential difference between the fuselage of the aircraft 10 and the rotor hub 300. It also avoids the rapid increase of the blade voltage on the rotor blade 200 due to the continuous increase of the deposited electrostatic charge. When the aircraft is struck by lightning, it reduces the situation where lightning attaches to the blade due to electrostatic deposition.

[0097] This prevents lightning from randomly entering the electric motor 100, which could cause performance degradation or direct failure of the electric motor 100. It also prevents static electricity from directly conducting lightning current into the electric motor 100 from the power supply and signal lines, thus avoiding safety threats to more electrical equipment.

[0098] Optionally, the electromagnetic shielding sleeve 1034 may be insulated from the conductive wire 1033. For example, the conductive wire 1033 may be a conductive wire with an internal conductive metal wire and an external insulating layer, the conductive metal wire being insulated from the electromagnetic shielding sleeve through the insulating layer. Alternatively, the conductive wire 1033 may also be a conductive metal wire, with an insulating coating on at least one of the outer wall of the conductive metal wire or the inner wall of the electromagnetic shielding sleeve 1034, the conductive metal wire being insulated from the electromagnetic shielding sleeve 1034 through the insulating coating.

[0099] Optionally, the electromagnetic shielding sleeve 1034 can be made of one of copper, aluminum, silver and nickel to prevent the electromagnetic influence of the conductive wire 1033 on other electronic components of the stator 101.

[0100] In one specific embodiment, the electromagnetic shielding sleeve 1034 can be a copper tube. The electromagnetic shielding sleeve 1034 is used to isolate or attenuate the electromagnetic radiation from the conductive wires 1033 inside the electromagnetic shielding sleeve 1034, preventing electromagnetic interference from the conductive wires 1033 inside the electromagnetic shielding sleeve 1034 to electronic components outside the electromagnetic shielding sleeve 1034. Furthermore, since copper tubes have high structural strength, using a copper tube for the electromagnetic shielding sleeve 1034 can also improve the structural strength of the conductive wires 1033.

[0101] Of course, in other specific embodiments, the material of the electromagnetic shielding sleeve 1034 can also be other metallic materials, conductive composite materials, fabrics and flexible materials, nanomaterials, etc., such as aluminum, aluminum alloys, steel, metal mesh, metal foil, conductive rubber, metal fiber blended fabrics, conductive coatings, carbon nanotubes, etc. In this embodiment, the electromagnetic shielding sleeve 1034 is a copper tube. Copper tubes have high shielding effectiveness and are applicable to the entire frequency band, thereby ensuring leak-free shielding and guaranteeing that the electronic components such as the windings and controller on the stator 101 will not be interfered with.

[0102] refer to Figure 4 and Figure 5According to some embodiments of the present invention, the conductive component 103 further includes a guide rail seat 1035 and an elastic element 1036. The guide rail seat 1035 is fixedly disposed in the stator 101. The guide rail seat 1035 is located on the side of the second conductive rail 1032 away from the first conductive rail 1031. The second conductive rail 1032 is mounted on the guide rail seat 1035, and the second conductive rail 1032 and the guide rail seat 1035 are insulated from each other. For example, the guide rail seat 1035 can be made of insulating material (such as rubber, insulating plastic, etc.), or the end face of the guide rail seat 1035 facing the second conductive rail 1032 can be coated with an insulating coating.

[0103] The guide rail base 1035 can be disc-shaped or annular. By setting the guide rail base 1035 in a disc-shaped or annular shape, a larger support area can be provided for the second conductive rail 1032, which is beneficial to improving the installation stability of the second conductive rail 1032.

[0104] An elastic element 1036 is disposed between the second conductive rail 1032 and the guide rail seat 1035 to apply an elastic force to the second conductive rail 1032, causing the second conductive rail 1032 to tend to move towards the first conductive rail 1031. The flexibility of the elastic element 1036 allows the second conductive rail 1032 to adaptively adjust its position within a certain range, maintaining sliding contact with the first conductive rail 1031 and improving the long-term conductive stability of the conductive component 103.

[0105] Optionally, the elastic element 1036 may include insulating elastic rubber, or the elastic element 1036 may also include an insulating spring, or the elastic element 1036 may also include an insulating washer, etc.

[0106] Thus, by setting the guide rail seat 1035 and the elastic element 1036, it is beneficial to reduce the wear caused by sliding friction between the first conductive rail 1031 and the second conductive rail 1032, avoid the increase in contact resistance caused by vibration and impact, and improve the stability of the low-impedance path between the first conductive rail 1031 and the second conductive rail 1032.

[0107] Continue to refer to Figure 4 and Figure 5According to some embodiments of the present invention, a portion of the structure of the second conductive rail 1032 facing the guide rail seat 1035 is recessed away from the guide rail seat 1035, forming a second cavity 1032c. A portion of the structure of the guide rail seat 1035 protrudes towards the second conductive rail 1032, forming a mounting protrusion 1035a. The mounting protrusion 1035a extends into the second cavity 1032c, so that the second conductive rail 1032 is mounted on the guide rail seat 1035. Exemplarily, the mounting protrusion 1035a can be interference-fitted with the second cavity 1032c, so that the second conductive rail 1032 is mounted on the guide rail seat 1035, thereby improving the installation stability of the second conductive rail 1032.

[0108] The guide rail base 1035 has a through hole extending along the central axis of the rotor 102. The conductive wire 1033 passes through the through hole, which helps to shorten the current transmission path and reduce wiring complexity.

[0109] According to some embodiments of this utility model, the second cavity 1032c extends along the central axis of the rotor 102 through one end of the second conductive rail 1032 facing the first conductive rail 1031. In other words, the second cavity 1032c extends along the central axis of the rotor 102 and communicates with the first cavity. Thus, in the scheme of sliding fit with a micro-gap between the conductive end face 1032a and the second end 1031b, and the conductive grease is provided in the conductive gap, even if some debris appears on the first conductive rail 1031 or the second conductive rail 1032 after the electric motor 100 has been running for a long time, it will flow into the second cavity 1032c under the action of the conductive grease, reducing the impact on the conductivity between the first conductive rail 1031 and the second conductive rail 1032.

[0110] refer to Figure 3 and Figure 7 In some embodiments, the electric motor 100 may also include a motor controller 105 and a motor rear cover, the motor rear cover may be disposed on the end of the cavity away from the rotor 102, and at least part of the motor controller is disposed in the cavity.

[0111] The motor controller 105 is disposed on the side of the stator 101 away from the propeller hub 300. The motor controller 105 includes a controller mounting plate with a controller through hole. The conductive component 103 passes through the controller through hole and extends to the outside of the electric motor 100. For example, the conductive wire 1033 of the conductive component 103 extends directly to the outside of the electric motor 100 through the controller through hole. Alternatively, a portion of the structure of the second conductive rail 1032 of the conductive component 103 may protrude toward the motor controller 105 and extend directly to the outside of the electric motor 100 through the controller through hole, thereby forming a reinforcing structure of the motor controller 105.

[0112] The structural strength of the controller mounting plate is not high, and it is prone to deformation or breakage when multiple electronic components are installed. This application utilizes a conductive component 103 that passes through the controller through hole on the controller mounting plate. The conductive component 103 can be insulated from the circuit board, and the conductive component 103 forms a reinforced structure for the controller mounting plate, thereby improving the strength of the controller mounting plate.

[0113] Therefore, in this application, the conductive component 103 can be led out to the outside of the electric motor 100 through the controller through hole, thus making effective use of the space of the electric motor 100. On the other hand, the conductive component 103 can be used to reinforce the motor controller 105.

[0114] Meanwhile, the conductive component 103 extends directly to the outside of the electric motor 100 through the controller through hole, which helps to avoid redundant paths around the motor controller 105 or other structures, and reduces resistance loss and electromagnetic radiation during current transmission.

[0115] Optionally, in some embodiments of this application, the motor rear cover may have a motor rear cover through hole, and the conductive component 103 may also pass through the motor rear cover through hole and lead to the outside of the electric motor 100.

[0116] Understandably, the conductive component 103 may pass through the controller through-hole and lead to the outside of the electric motor, or it may pass through the motor rear cover through-hole and lead to the outside of the electric motor, or the conductive component 103 may pass through both the controller through-hole and the motor rear cover through-hole and lead to the outside of the electric motor.

[0117] refer to Figure 7 According to some embodiments of this utility model, the motor controller 105 includes a first type of electronic component 1052 and a second type of electronic component 1053. The electromagnetic sensitivity of the first type of electronic component 1052 can be lower than that of the second type of electronic component 1053. In other words, in the relevant technical field, the first type of electronic component 1052 can be a non-electromagnetically sensitive electronic and electrical component, and the second type of electronic component 1053 can be an electromagnetically sensitive electronic and electrical component.

[0118] In some embodiments, an electromagnetic shielding structure may be provided inside the motor controller 105. When the conductive wire 1033 passes through the controller through hole to the outside of the electric motor 100, the electromagnetic shielding structure may be an electromagnetic shielding sleeve 1034 sleeved on the conductive wire 1033. The material of the electromagnetic shielding sleeve 1034 may be an electromagnetic field shielding material (e.g., copper). The electromagnetic shielding structure can shield the electromagnetic field generated by lightning and static electricity conduction by the conductive wire 1033. Alternatively, the electromagnetic shielding structure may also include a strength-enhancing support structure for the motor controller 105 and other structures, or the electromagnetic shielding structure may be a separate shielding tube.

[0119] Understandably, the layout design of the internal components of the electric motor 100 must meet the electromagnetic field limits of the environment in which the electronic components are allowed to operate. Taking a single shielding tube as an example, because static electricity and lightning have some low-frequency energy, the non-electromagnetically sensitive electronic and electrical components outside the shielding structure, i.e., the first type of electronic components 1052, are arranged at a certain distance outside the shielding structure. The placement position of the first type of electronic components 1052 can be calculated by simulating the target distance based on the designed electromagnetic interference target. The non-inductive electronic components are arranged at a design target distance outside the conductive wire shielding tube, while the electromagnetically sensitive electronic and electrical components, i.e., the second type of electronic components 1053, are arranged as far away from the outside of the conductive wire shielding tube as possible. In other words, the distance between the second type of electronic components 1053 and the controller through hole is greater than the distance between the first type of electronic components 1052 and the controller through hole.

[0120] In a specific embodiment, such as Figure 7 The annular region shown in the middle m has a conductive line 1033 at its center. The insulating sleeve 1034 is between the conductive line 1033 and the annular region shown in the middle m. At this time, the insulating sleeve 1034 is a shielding tube, forming an electromagnetic shielding structure, which is beneficial to improving the safety of other structures in the electric motor 100.

[0121] Understandably, the second type of electronic component 1053 can be arranged as far as possible from the outside of the shielding tube of the conductive wire 1033, not limited to the two-dimensional space where the motor controller 105 is located. Alternatively, in the three-dimensional space where the motor controller 105 is located, the second type of electronic component 1053 should also be arranged as far as possible from the outside of the shielding tube, for example, the second type of electronic component 1053 can be placed at the farthest point above the shielding tube, in order to reduce the impact of lightning electrostatic current conduction on the electrical equipment inside the motor, so that the motor and the motor controller 105 and other structures inside the motor are not subject to electromagnetic interference when lightning and electrostatic current are conducted in the motor.

[0122] refer to Figure 1 and Figure 2 Secondly, embodiments of this application also provide an electric propulsion device, which may include: a blade 200, a hub 300, and the aforementioned electric motor 100, wherein the blade 200 and the hub 300 are electrically connected; and the rotor 102 of the electric motor 100 is electrically connected to the hub 300.

[0123] Existing propulsion systems cannot discharge static electricity on the blades in a timely manner. The accumulation of charge leads to an increase in voltage on the blades and the terminals connected to the motor rotor. High voltage may cause discharge at the blade tips, and the electromagnetic pulse generated by the discharge may interfere with airborne communication, navigation, and control systems. At this time, due to the potential difference between the blades and the fuselage, the discharge at small gaps such as motor bearings under high potential difference will cause electrolytic corrosion of the electric propulsion motor bearings, affecting the bearing's service life. Furthermore, the accumulation of static electricity on the blades will affect the breakdown voltage between the aircraft and the surrounding air, potentially becoming a priority channel for lightning strikes and increasing the probability of lightning attaching to the blades.

[0124] The electric propulsion device of this invention, by using the aforementioned electric motor 100, forms a current conduction path that conducts current from inside the electric motor 100 to outside. The current on the propeller blades 200 is conducted through the hub 300 to the shaft 1021 of the electric motor 100. Then, through the designed conductive path, the current is conducted to the outside of the electric motor 100, thus achieving the goal of conducting current from the propeller blades 200 to the outside of the electric motor 100. This ensures that the potential of the propeller blades 200 is the same as that of the aircraft 10 body, preventing a potential difference between the aircraft 10 body and the propeller blades 200. It also avoids a rapid increase in the voltage of the propeller blades 200 due to the continuous increase of accumulated static charge. Furthermore, it reduces the probability of lightning strikes to the propeller blades 200 due to static charge accumulation when the aircraft 10 is struck by lightning. This helps to prevent lightning and static currents on the propeller blades 200 from affecting the internal electrical components of the electric motor 100, thereby extending the service life of the electric motor 100.

[0125] In some embodiments, the electric propulsion device may further include a pitch mechanism 400, which is connected to the blade root and the hub 300 of the blade 200. The connection between the pitch mechanism 400 and the blade root is insulated, and the connection between the pitch mechanism 400 and the hub 300 is also insulated. The pitch mechanism 400 may include a pitch pusher, which is mounted within the hub 300 and moves vertically along the axial direction of the propeller main shaft under the action of a pitch motor. The pitch pusher is connected to multiple blades 200 via multiple connecting rods, so that when it moves vertically, it also drives the corresponding blade 200 to oscillate relative to the hub 300 via the connecting rods.

[0126] By insulating the connection between the pitch mechanism 400 and the rotor hub 300, such as by using an insulating coating material or an insulating structural component, lightning static electricity is prevented from being conducted from the rotor root and rotor hub 300 to the pitch mechanism.

[0127] Thirdly, embodiments of this application also provide an aircraft 10, which may include: an airframe and the aforementioned engine or the aforementioned electric propulsion device. The electric motor 100 is located inside the airframe; or, the electric motor 100 of the electric propulsion device is located inside the airframe.

[0128] The aircraft 10 of this invention, by using the aforementioned electric motor 100 or electric propulsion device, helps to avoid the impact of lightning and static electricity currents on the propeller blades 200 on the internal electrical components of the electric motor 100, thereby reducing the maintenance cost of the aircraft 10 and extending the service life of the electric motor 100.

[0129] Understandably, the aircraft 10 in this application embodiment can be an electric vertical take-off and landing (eVTOL) aircraft, or of course, other aircraft.

[0130] Figure 1 This is a schematic diagram of an aircraft 10 provided in an embodiment of this application. Wherein, Figure 1 The aircraft 10 shown is for illustrative purposes only and does not constitute a limitation on the specific structure and shape of the aircraft 10.

[0131] This application provides an aircraft 10, which can be an electric vertical take-off and landing (eVTOL) aircraft, or other types of aircraft 10.

[0132] like Figure 1 As shown, the aircraft 10 includes a fuselage 11, wings 12, and a tail 13. The fuselage 11 has a symmetrical structure; the remaining structure and shape of the fuselage 11 are not limited and can refer to the existing fuselage 11 structure of aircraft 10. The wings 12 are fixedly connected to the fuselage 11, and the structure of the wings 12 can also refer to the fixed wing 12 structure of existing aircraft 10, which will not be described further here. The tail 13 is fixedly located at the tail of the fuselage 11, and the tail 13 is integrally formed with the fuselage 11 or mechanically connected, and has a symmetrical structure. The structure of the tail 13 can also refer to the existing tail 13 structure of aircraft 10, which will not be described further here.

[0133] It should be noted that in some scenarios, the aircraft 10 may also include the fuselage 11 and the wings 12, that is, the aircraft 10 does not include the tail 13.

[0134] like Figure 1 As shown, the aircraft 10 also includes an electric propulsion system, which can be used to provide power to the aircraft 10. The number of electric propulsion systems can be one or more, for example... Figure 1 As shown, the aircraft 10 includes eight electric propulsion devices.

[0135] Electric propulsion devices are installed in the fuselage 11 and / or wings 12 and / or tail 13, for example Figure 1 As shown, electric propulsion devices are symmetrically mounted on both the wings 12 and the tail 13. However, in some scenarios, the electric propulsion devices are mounted on the fuselage 11, while those on the wings 12 and tail 13 are not. In other scenarios, the electric propulsion devices are mounted on the wings 12, while those on the fuselage 11 and tail 13 are not. In still other scenarios, the electric propulsion devices are mounted on the tail 13, while those on the fuselage 11 and wings 12 are not.

[0136] See also Figure 1 As shown, the aircraft 10 also includes an arm 14 and a nacelle 15, both of which are used to connect to an electric propulsion system to mount the electric propulsion system on the fuselage 11, wing 12, or tail 13. Of course, in some scenarios, the aircraft 10 may also include only one of the arms 14 and the nacelle 15.

[0137] In some embodiments, such as Figure 1 As shown, the electric propulsion device is mounted on the wing 12 via arm 14. In other embodiments, the electric propulsion device may also be mounted on the wing 12 via nacelle 15 (not shown in the figure).

[0138] In some embodiments, as shown, the electric propulsion device is mounted on the tail fin 13 via a nacelle 15. In other embodiments, the electric propulsion device may also be mounted on the tail fin 13 via an arm 14 (not shown in the figure).

[0139] In some examples, the electric propulsion system on the aircraft 10 may include a fixed electric propulsion system that is fixedly connected to any one of the fuselage 11, wing 12 and tail 13.

[0140] In some examples, the electric propulsion system on the aircraft 10 may include a tilt electric propulsion system, with a tilting mechanism between the tilt electric propulsion system and any one of the fuselage 11, wing 12 and tail 13, the tilting mechanism being used to adjust the tilt angle of the tilt electric propulsion system.

[0141] In some examples, all electric propulsion devices installed on the aircraft 10 are fixed electric propulsion devices.

[0142] In other examples, all the electric propulsion devices installed on the aircraft 10 are tilt electric propulsion devices.

[0143] The electric propulsion system installed on the aircraft 10 includes some fixed electric propulsion systems and some tilting electric propulsion systems, for example... Figure 1 As shown, four of the electric propulsion devices are fixed electric propulsion devices, and the remaining four are tilting electric propulsion devices. The fixed electric propulsion devices are located outside the tilting electric propulsion devices.

[0144] The electric propulsion device may include an electric motor 100 and a propeller. The electric motor 100 includes a power motor, a motor controller 105, and cables, etc., and can convert electrical energy into mechanical energy.

[0145] An electric motor 100 is mounted on the arm 14 or nacelle 15, and a propeller is mounted on one side of the electric motor 100. The electric motor 100 is connected to the propeller in a drive system and is used to drive the propeller to rotate in order to provide power for the aircraft 10.

[0146] In this embodiment, the electric motor 100 includes a power motor, which can be mounted on the fuselage 11 and / or wing 12 and / or tail 13 via a mounting bracket.

[0147] The propeller can be mounted on one side of the power motor, and the power motor is connected to the propeller for transmission. The power motor is used to drive the propeller to rotate.

[0148] In some embodiments, the exterior of the body may be covered with a skin, which may be a conductive component; the conductive component 103 of the electric motor 100 is conductively connected to the skin.

[0149] By installing a skin on the fuselage, a current guiding path is formed, which is: blade 200 - hub 300 - shaft 1021 - first conductive rail 1031 - second conductive rail 1032 - conductive line 1033 - skin. Through this lightning and electrostatic low impedance transmission conductive path, the current can be guided to the skin according to the planned path, preventing high voltage and high current from damaging sensitive components inside the motor, and at the same time preventing charge accumulation from interfering with other electrical components inside the aircraft 10.

[0150] In this way, lightning and static electricity deposited on the propeller blades 200 can be directly conducted to the aircraft skin. This makes the propeller blades 200 and the aircraft body 10 have the same potential, forming an equipotential body to prevent a potential difference between the aircraft body and the propeller blades 200. At the same time, it avoids a rapid increase in the voltage of the propeller blades 200 due to the continuous increase of static charge deposited on them. This reduces the probability of lightning attaching to the propeller blades 200 due to static electricity deposits when the aircraft 10 is struck by lightning.

[0151] Optionally, the skin can be a metallic conductive component or a conductive component made of composite materials. For example, the skin can be made of aluminum alloy, a mainstream material, which is lightweight, has moderate strength, low cost, and is easy to process; the skin can also be made of titanium alloy, which has an extremely high strength-to-weight ratio, high temperature resistance (supersonic flight), and corrosion resistance. The skin can also be a composite material, such as a skin integrated with composite materials and metal mesh. This type of skin is lightweight, high-strength, fatigue-resistant, and highly designable. For example, a skin integrated with carbon fiber reinforced polymer and metal mesh.

[0152] The implementation principle of an electric motor 100, an electric propulsion device, and an aircraft 10 according to an embodiment of this application is as follows: A conductive component 103 is located inside the stator 101 and is conductively connected to the rotating shaft 1021. The conductive component 103 is used to guide the current transmitted by the rotor hub 300 to the outside of the electric motor 100. By placing the conductive component 103 inside the stator 101 and directly conductively connecting it to the rotating shaft 1021, and guiding the current to the outside of the electric motor 100, a dedicated low-impedance path is formed. Simultaneously, insulation is provided between the rotor 102 and the stator 101 to block the risk of current directly penetrating the stator 101. The aforementioned low-impedance path structure is simple, with low internal inductive and capacitive reactance, which is beneficial for efficiently dissipating current generated by lightning or static electricity, avoiding random discharge of current between the rotor 102 and the stator 101, thereby protecting the core components of the electric motor 100 from damage and significantly improving the protection effect against lightning strikes and static electricity.

[0153] Under the planned lightning and static electricity path, when lightning and static electricity flow, they are only conducted along this path, preventing lightning from randomly entering the electric motor 100 and causing performance degradation or direct failure. It also prevents lightning and static electricity from directly conducting current into the motor from the power and signal lines, thus avoiding safety threats to other electrical equipment. Lightning and static electricity current will not flow on the stator 101, and the electromagnetic field generated during lightning and static electricity flow will not affect the motor windings. The insulation treatment at low-impedance paths and small gaps also minimizes the possibility of breakdown and conduction through these gaps.

[0154] Finally, it should be noted that other embodiments of this utility model will readily occur to those skilled in the art upon consideration of the specification and practice of the utility model disclosed herein. This utility model is intended to cover any variations, uses, or adaptations of this utility model that follow the general principles of this utility model and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this utility model is limited only by the appended claims.

Claims

1. An electric motor engine (100) characterized by, include: The stator (101) has a cavity; The rotor (102) is rotatably connected to the stator (101) via a rotating shaft (1021); and the rotor (102) is insulated from the stator (101); the rotating shaft (1021) is connected to the cavity. A conductive component (103) is disposed in the cavity. One end of the conductive component (103) is electrically connected to the rotating shaft (1021), and the other end extends to the outside of the electric motor (100).

2. The electric motor (100) according to claim 1, characterized in that, The rotor (102) is rotatably sleeved on the outside of the stator (101), and part of the structure of the rotating shaft (1021) extends into the cavity; a bearing (104) is provided between the rotating shaft (1021) and the stator (101), the bearing (104) includes an inner bearing ring (1041), an outer bearing ring (1042), and a bearing rolling element (1043) rotatably disposed between the inner bearing ring (1041) and the outer bearing ring (1042), the inner bearing ring (1041) is connected to the rotating shaft (1021), and the outer bearing ring (1042) is connected to the stator (101); The connection between the rotating shaft (1021) and the inner ring of the bearing (1041) is insulated; and / or, the bearing rolling element (1043) is an insulated element; and / or, the connection between the outer ring of the bearing (1042) and the stator (101) is insulated; and / or, the opposing surfaces of the rotor (102) and the stator (101) are insulated.

3. The electric motor (100) according to claim 2, characterized in that, The conductive component (103) includes a first conductive rail (1031) and a second conductive rail (1032), at least a portion of the structure of the first conductive rail (1031) is located in the cavity, and the first conductive rail (1031) is connected to the rotating shaft (1021). The second conductive rail (1032) is located at one end of the first conductive rail (1031) extending away from the rotor (102) along the central axis of the rotor (102), and the second conductive rail (1032) is electrically connected to the first conductive rail (1031).

4. The electric motor (100) according to claim 3, characterized in that, The first conductive rail (1031) has a first end (1031a) and a second end (1031b) extending along the central axis of the rotor (102), and the first end (1031a) is connected to the rotating shaft (1021). The second conductive rail (1032) has a conductive end face (1032a) at one end facing the first conductive rail (1031), and at least a portion of the surface of the second end (1031b) is electrically connected to the conductive end face (1032a).

5. The electric motor (100) according to claim 4, characterized in that, A portion of the structure at one end of the second conductive rail (1032) facing the first conductive rail (1031) is recessed away from the first conductive rail (1031) to form a first cavity. At least a portion of the structure at the second end (1031b) extends into the first cavity, and the inner wall of the first cavity constitutes the conductive end face (1032a); and / or, In the direction extending away from the first conductive rail (1031) along the central axis of the rotor (102), the diameter of the first cavity gradually decreases. In the direction extending toward the first cavity along the central axis of the rotor (102), the diameter of the second end (1031b) gradually decreases. The peripheral wall of the second end (1031b) is electrically connected to the conductive end face (1032a).

6. The electric motor (100) according to claim 4, characterized in that, A conductive gap is provided between at least a portion of the surfaces of the conductive end face (1032a) and the second end (1031b), and conductive grease is provided in the conductive gap; Alternatively, a conductive rolling element may be provided between the conductive end face (1032a) and at least a portion of the surface of the second end (1031b), and conductive grease may be applied between the conductive rolling element and at least a portion of the surface of the conductive end face (1032a) and the second end (1031b).

7. The electric motor (100) according to claim 6, characterized in that, The conductive component (103) further includes a conductive wire (1033) and an electromagnetic shielding sleeve (1034). One end of the conductive wire (1033) is fixedly connected to the second conductive rail (1032), and the other end extends to the outside of the electric motor (100). The electromagnetic shielding sleeve (1034) is fitted over the conductive wire (1033).

8. The electric motor (100) according to claim 7, characterized in that, The conductive component (103) further includes a guide rail seat (1035) and an elastic element (1036). The guide rail seat (1035) is fixedly disposed inside the stator (101). The guide rail seat (1035) is located on the side of the second conductive rail (1032) away from the first conductive rail (1031). The second conductive rail (1032) is mounted on the guide rail seat (1035), and the second conductive rail (1032) and the guide rail seat (1035) are insulated from each other. The elastic element (1036) is disposed between the second conductive rail (1032) and the guide rail seat (1035) for applying an elastic force to the second conductive rail (1032) so that the second conductive rail (1032) tends to move toward the first conductive rail (1031).

9. The electric motor (100) according to claim 8, characterized in that, The second conductive rail (1032) has a portion of its surface facing the guide rail seat (1035) recessed away from the guide rail seat (1035) to form a second cavity (1032c). A portion of the structure of the guide rail seat (1035) protrudes toward the second conductive rail (1032) to form a mounting protrusion (1035a), which extends into the second cavity (1032c) so that the second conductive rail (1032) is mounted on the guide rail seat (1035). And / or, the guide rail seat (1035) has a seat through hole extending along the central axis of the rotor (102), through which the conductive wire (1033) passes.

10. The electric motor (100) according to claim 1, characterized in that, Also includes: The motor controller (105) and the motor rear cover are disposed on one end of the cavity away from the rotor (102), and at least part of the motor controller is disposed in the cavity of the stator (101); the motor controller (105) includes a controller mounting plate, the controller mounting plate is provided with a controller through hole, the conductive component (103) passes through the controller through hole and leads to the outside of the electric motor (100); and / or, the motor rear cover has a motor rear cover through hole, the conductive component passes through the motor rear cover through hole and leads to the outside of the electric motor.

11. The electric motor (100) according to claim 10, characterized in that, The motor controller (105) includes a first type of electronic component (1052) and a second type of electronic component (1053), wherein the electromagnetic sensitivity of the first type of electronic component (1052) is lower than that of the second type of electronic component (1053). The distance between the first type of electronic component (1052) and the through hole of the controller is less than the distance between the second type of electronic component (1053) and the through hole of the controller.

12. An electric propulsion device, characterized in that, include: blade (200); The hub (300) is electrically connected to the blade (200); The electric motor (100) according to any one of claims 1-11, wherein the rotor (102) of the electric motor (100) is electrically connected to the rotor hub (300).

13. The electric propulsion device according to claim 12, characterized in that, Also includes: A pitch mechanism (400) is connected to the root of the blade (200) and the hub (300). The connection between the pitch mechanism (400) and the propeller root is insulated, and the connection between the pitch mechanism (400) and the propeller hub (300) is insulated.

14. An aircraft (10), characterized in that, include: The body, the body being externally covered with a skin, the skin being a conductive component; The electric motor (100) according to any one of claims 1-11, or the electric propulsion device according to claim 12 or 13, wherein the conductive component (103) of the electric motor (100) is electrically connected to the skin.

Images