WO2020024488A1 - Propeller, power assembly and unmanned aerial vehicle - Google Patents

Abstract

A propeller (100), a power assembly (30) and an unmanned aerial vehicle (40). The propeller comprises a hub (10) and a plurality of blades (20) connected to the hub, the blades as a whole resembling a "saber shape", each blade comprising an upper blade face, a lower blade face, a leading edge (21) and a trailing edge (22), the leading edge and the trailing edge being located on two sides of the blade, and the leading edge and the trailing edge connecting the upper blade face and the lower blade face, so as to define the structure of the blades from three aspects including airfoil distribution, chord length (C) distribution and torsion angle (α) distribution of the blades, ensuring that the blades have a better working performance, effectively improving the aerodynamic efficiency of the propeller, and reducing the noise level. Using the propeller for the power assembly and the unmanned aerial vehicle can correspondingly improve the efficiency of the power assembly and the unmanned aerial vehicle, thereby effectively extending duration of flight of the unmanned aerial vehicle, reducing the noise level thereof, and improving the flight performance of the unmanned aerial vehicle.

Description

Propeller, power pack and unmanned aerial vehicle

This application claims priority from a Chinese patent application filed on August 01, 2018 with the Chinese Patent Office, application number 2018212322175, and application name "Propeller, Powertrain and Unmanned Aerial Vehicle", the entire contents of which are incorporated herein by reference in.

Technical field

The present application relates to the technical field of unmanned aerial vehicle manufacturing, and in particular, to a propeller, a power assembly, and an unmanned aerial vehicle.

Background technique

As one of the important parts of unmanned aerial vehicles, the propellers on unmanned aerial vehicles are used to convert the rotational energy of the motor output shaft into thrust or lift to achieve the take-off, steering, and hovering of unmanned aerial vehicles. The main source of power, and the aerodynamic efficiency of the propeller directly affects the life of the UAV.

The blades of the existing propellers are mostly flat plate-like structures, and the shape of the blades are mostly wide roots and narrow tips, that is, the width of the blade near the hub is larger, and the width of the blade far from the hub is smaller .

The existing shape of the blade profile results in low aerodynamic efficiency of the propeller, and high resistance to the flight of the unmanned aerial vehicle, which eventually leads to the problems of low flying speed, short endurance time, and high noise level during the flight of the unmanned aerial vehicle, which seriously affects unmanned aircraft. Flight performance of the aircraft.

Summary of the invention

In order to solve at least one of the problems mentioned in the background art, the present application provides a propeller, a power assembly and an unmanned aerial vehicle, which can improve the endurance time of the propeller and reduce the noise level.

In order to achieve the above object, in one aspect, the present application provides a propeller including a hub and a blade connected to the hub. The blade includes an upper blade surface, a lower blade surface, a leading edge, and a trailing edge. The leading edge and trailing edge are located on both sides of the blade, the leading edge and the trailing edge connect the upper blade surface and the lower blade surface, the radius of the hub is r, and the radius of the propeller Is R, where:

The maximum relative camber of the blade at a position r-30% × R from the center of the hub is 5% ± 0.3%;

At a distance from the center of the hub of 30% × R to 90% × R, the maximum relative camber of the blade is 5.8% ± 0.1%;

The maximum relative camber of the blade is at a position of 90% × R to 100% × R from the center of the hub; 4.8% ± 0.1%;

The maximum relative camber of the blade is the ratio of the maximum camber of the airfoil of the blade to the chord length of the blade.

In some embodiments, the maximum relative camber of the blade is 5% at a position r-30% × R from the center of the hub;

The maximum relative camber of the blade at a position 30% × R to 90% × R from the center of the hub is 5.8%;

At a distance from the center of the hub of 90% × R to 100% × R, the maximum relative camber of the blade is 4.8%.

In some embodiments, at a position r-30% × R from the center of the hub, the position of the maximum camber of the blade is a chord length 38.5% ± 5% from the leading edge;

At a position 30% × R to 90% × R from the center of the hub, the position of the maximum camber of the blade is a chord length 43.5% ± 0.3% from the leading edge.

In some embodiments, at a position 90% × R to 100% × R from the center of the hub, the maximum camber position of the blade is a chord length 35.5% ± 0.3% from the leading edge.

In some embodiments, at a position r-30% × R from the center of the hub, the maximum relative thickness of the blade is 11% ± 0.5%;

At a position that is 90% × R to 100% × R from the center of the hub, the maximum relative thickness of the blade is 5.1% ± 0.3%;

The maximum relative thickness of the paddle at a position 30% × R to 90% × R from the center of the hub is 7.1% ± 0.3%;

The maximum relative thickness of the blade is the ratio of the maximum thickness of the airfoil of the blade to the chord length of the blade.

In some embodiments, at a position r-30% × R from the center of the hub, the position of the maximum thickness of the blade is a chord length 27.5% ± 0.5% from the leading edge;

At a position 30% × R ～ 90% × R from the center of the hub, the position of the maximum thickness of the blade is a chord length 18% ± 0.3% from the leading edge;

At a position 90% × R to 100% × R from the center of the hub, the position of the maximum thickness of the blade is a chord length 30.5% ± 0.3% from the leading edge.

In some embodiments, at a position 30% × R from the center of the hub, the twist angle of the blade is 20 ° ± 0.5 °;

At a position 50% × R from the center of the hub, the twist angle of the blade is 15 ° ± 0.5 °;

At a distance from the center of the hub to 75% of the radius of the propeller × R, the twist angle of the blade is 13 ° ± 0.3 °;

At a distance from the center of the hub to 85% of the radius of the propeller × R, the twist angle of the blade is 10.5 ° ± 0.3 °;

Wherein, the twist angle of the blade is the angle between the chord line of the blade and the horizontal plane.

In some embodiments, at a position from r to 15% × R from the center of the hub, the twist angle of the blade is 16 ° ± 0.5 °.

In some embodiments, at a position 100% × R from the center of the hub, the twist angle of the blade is 10 ° ± 0.3 °.

In some embodiments, the ratio of the chord length of the blade to the diameter of the propeller is 8% ± 0.3% at a position r-30% × R from the center of the hub;

At a position 50% × R from the center of the hub, the ratio of the chord length of the blade to the diameter of the propeller is 9.5% ± 0.1%;

At a position 75% × R from the center of the hub, the ratio of the chord length of the blade to the diameter of the propeller is 7.6% ± 0.05%;

At a position that is 90% × R from the center of the hub, the ratio of the chord length of the blade to the diameter of the propeller is 6.2% ± 0.05%.

In some embodiments, the ratio of the chord length of the blade to the diameter of the propeller is 7% ± 0.5% at a position from r to 15% × R from the center of the hub.

In some embodiments, at a position 100% × R from the center of the hub, the ratio of the chord length of the blade to the diameter of the propeller is 1.9% ± 0.05%.

In some embodiments, the trailing edge of the blade is straight.

In some embodiments, the upper leaf surface, the lower leaf surface, and the leading edge surface are all smooth curved surfaces, and the upper leaf surface, the lower leaf surface, and the leading edge surface are And a smooth transition from the edge surface of the trailing edge.

In some embodiments, the chord length of the blade increases from the heel of the blade to the tip of the blade and then decreases, and the chord length of the blade tip is shorter than the The length of the blade's heel.

In some embodiments, the Reynolds number of the propeller ranges from 10 ⁴ to 5 × 10 ⁵ .

In order to solve the above technical problem, the present application further provides a power assembly, which includes a motor and a propeller as described above, and a hub of the propeller is connected to an output shaft of the motor.

In order to solve the above technical problems, an embodiment of the present application further provides an unmanned aerial vehicle, which includes a fuselage, an airframe connected to the airframe, and the above-mentioned power component installed on the airframe.

The propellers, power components, and unmanned aerial vehicles provided by this application can ensure better working performance of the propellers by setting specific airfoil distribution, twist angle distribution, and chord length distribution for the propeller blades. Efficiency and reduce its noise level. Further, the application of the propeller to power components and unmanned aerial vehicles can correspondingly improve the efficiency of the power components and unmanned aerial vehicles, which can effectively extend the life of the unmanned aerial vehicle and reduce its noise level, and ultimately improve the unmanned aerial vehicle. Flight performance.

The structure of the present application and other objects and beneficial effects of the utility model will be more apparent and comprehensible through the description of the preferred embodiments in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly explain the embodiments of the present application or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description These are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained according to these drawings without paying creative labor.

FIG. 1 is a schematic diagram of an unmanned aerial vehicle according to an embodiment of the present application; FIG.

2 is a top view of a propeller provided in an embodiment of the present application;

3 is a front view of the propeller shown in FIG. 2;

4 is a sectional view of a blade of the propeller shown in FIG. 2;

5 is a cross-sectional view of the A-A cross section of the propeller shown in FIG. 2;

6 is a cross-sectional view of a B-B cross section of the propeller shown in FIG. 2;

7 is a cross-sectional view of the C-C cross section of the propeller shown in FIG. 2;

8 is a cross-sectional view of the D-D section of the propeller shown in FIG. 2;

9 is a sectional view of an E-E cross section of the propeller shown in FIG. 2;

Fig. 10 is a cross-sectional view taken along the F-F section of the propeller shown in Fig. 2.

Reference sign description:

100-propeller;

10-hub;

20-paddle;

21-leading edge;

22- 后 缘 ； 22-trailing edge;

23-string

24-mid arc line;

L-propeller diameter;

R-propeller radius;

T-blade maximum thickness;

C-blade chord length;

F-the maximum camber of the blade;

α-twist angle

30-Power components;

31-Motor;

40-unmanned aerial vehicle;

41-Airframe;

42-machine arm.

detailed description

In order to make the purpose, technical solution, and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described in more detail with reference to the accompanying drawings in the preferred embodiments of the present application. In the drawings, the same or similar reference numerals indicate the same or similar components or components having the same or similar functions throughout. The described embodiments are part of the embodiments of this application, but not all of them. The embodiments described below with reference to the drawings are exemplary, and are intended to explain the present application, and should not be construed as limiting the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application. The embodiments of the present application will be described in detail below with reference to the drawings.

In the description of this application, it should be noted that the terms "center", "upper", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing this application and simplified description, and does not indicate or imply that the device or element referred to must have a specific orientation, a specific orientation Construction and operation are therefore not to be construed as limitations on the present application. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be interpreted as indicating or implying relative importance.

In the description of this application, it should be noted that the terms "installation", "connected", and "connected" should be understood in a broad sense, unless explicitly stated and limited otherwise. For example, a fixed connection may be made, or an intermediate connection may be used. The medium is indirectly connected, which can be the internal connection of the two elements or the interaction between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific situations.

In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

The propeller provided in the embodiments of the present application is a motor with high aerodynamic efficiency and low noise level. The propeller is mounted on the motor, and can be applied to any application field of mechatronics, especially to various motor-driven applications. On movable objects, including but not limited to unmanned aerial vehicles (UAVs), ships, and robots. In the embodiment of the present application, an unmanned aerial vehicle is taken as an example for description. Applying the propeller provided in the embodiment of the present application to an unmanned aerial vehicle can effectively extend the hovering time of the unmanned aerial vehicle and reduce the noise level of the unmanned aerial vehicle.

FIG. 1 is a schematic diagram of an unmanned aerial vehicle according to an embodiment of the present application. Please refer to FIG. 1, which is a schematic structural diagram of an unmanned aerial vehicle provided by one embodiment of the present application. The structure of the unmanned aerial vehicle 40 includes a fuselage 41, four arms 42 extending from the fuselage 41 and connected to the fuselage 41, and a power assembly 30 respectively mounted on each of the arms 42. That is, the unmanned aerial vehicle 40 of the present application is a quadrotor unmanned aerial vehicle, and the number of the power components 30 is four. In other possible embodiments, the unmanned aerial vehicle 40 may be any other suitable type of rotary unmanned aerial vehicle, such as a double-rotor unmanned aerial vehicle, a six-rotor unmanned aerial vehicle, and the like. Where the power pack 30 is applied to other types of unmanned aerial vehicles, the number of the power pack 30 may be changed according to actual needs, which is not limited in the embodiment of the present application.

In other possible embodiments, the unmanned aerial vehicle 40 may further include a gimbal (not shown), which is connected to the fuselage 41 and is located at the bottom of the fuselage 41. The gimbal is used to carry a high-definition digital camera or other video cameras. The device is used to eliminate the disturbance of the high-definition digital camera or other camera device, and to ensure that the video captured by the camera or other camera device is clear and stable.

In an embodiment of the present application, the arm 42 is fixedly connected to the body 41. Preferably, the arm 42 is integrally formed with the body 41. In other possible embodiments, the arm 42 may also be connected to the body 41 in a manner that it can be unfolded or folded relative to the body 41. For example, the arm 42 may be connected to the main body 41 through a rotating shaft mechanism, so that the arm 42 can be unfolded or folded relative to the main body 41.

In an embodiment of the present application, the power assembly 30 includes a motor 31 and a propeller 100 driven by the motor 31. The propeller 100 is installed on the output shaft of the motor 31. The propeller 100 is driven by the motor 31 to generate an unmanned aerial vehicle. 40 lift or thrust for flight. The motor 31 may be any suitable type of motor, such as a brushed motor, a brushless motor, a DC motor, a stepper motor, an AC induction motor, and the like. The power assembly 30 of the present application further includes an electronic governor (not shown) disposed in a cavity formed by the fuselage 41 or the arm 42, and the electronic governor is used to generate an electronic governor according to an accelerator controller or an accelerator generator. The throttle signal generates a motor control signal for controlling the rotation speed of the motor to obtain a flying speed or a flying attitude required by the unmanned aerial vehicle.

In one implementation, the throttle controller or the throttle generator may be a flight control module of an unmanned aerial vehicle. The flight control module senses the environment around the UAV through various sensors and controls the flight of the UAV. The flight control module may be a processing module (Application Unit), an Application Specific Integrated Circuit (ASIC), or a Field Programmable Gate Array (FPGA).

When the user inputs an instruction to control the flying attitude of the UAV through the remote control, the UAV's flight control module sends a throttle signal to the electric control board. The electric control board receives the throttle signal, generates and sends the signal to the motor for The motor performs motor control signals such as starting and controlling the rotation speed of the motor.

FIG. 2 is a top view of a propeller provided in an embodiment of the present application. FIG. 3 is a front view of the propeller in FIG. 2. 4 is a cross-sectional view of a blade of the propeller in FIG. 2. Fig. 5 is a cross-sectional view of the A-A cross section of the propeller in Fig. 2. Fig. 6 is a cross-sectional view taken along the B-B section of the propeller in Fig. 2. Fig. 7 is a cross-sectional view taken along the C-C section of the propeller in Fig. 2. Fig. 8 is a cross-sectional view taken along the D-D section of the propeller in Fig. 2. FIG. 9 is a cross-sectional view of the E-E cross section of the propeller in FIG. 2. Fig. 10 is a cross-sectional view of the F-F cross section of the propeller in Fig. 2.

Referring to FIG. 2 to FIG. 10, an embodiment of the present application provides a propeller 100 including a hub 10 and at least two blades 20 connected to the hub 10 (the two blades are taken as an example in the figure. Description). In an embodiment of the present application, the at least two blades 20 are fixedly connected to the hub 10. Preferably, the at least two blades 20 are integrally formed with the hub 10. In other possible embodiments, the at least two blades 20 may also be connected to the hub 10 in a manner of being unfolded or folded relative to the hub 10. For example, the at least two blades 20 may be connected to the hub 10 through a rotating shaft, respectively, so as to realize the expansion or folding of the at least two blades 20 relative to the hub 10.

The hub 10 is used to fixedly connect the propeller 100 to an output shaft of the motor 31. In an embodiment of the present application, the propeller hub 10 is provided with internal threads, and the output shaft of the motor 31 is provided with external threads corresponding to the internal threads. Through the cooperation of the internal and external threads, The screw connection between the propeller 100 and the motor 31 is realized. In other embodiments, the output shaft of the motor 31 can also be locked in the propeller hub 10 by a screw lock, or the output shaft of the motor 31 can be connected to the propeller hub 10 by knurling. In other implementations, a groove may be provided on the motor 31, and a claw portion matching the groove is provided on the propeller 100. The propeller 100 is rotationally connected to the motor 31, and the claw portion on the propeller 100 is connected to the motor 31. The latching of the upper groove realizes the connection between the propeller 100 and the motor 31.

The paddle 20 includes an upper blade surface, a lower blade surface, a leading edge 21 and a trailing edge 22, the leading edge 21 and the trailing edge 22 are located on both sides of the paddle 20, and the leading edge 21 and the trailing edge 22 connect the upper and lower leaves. surface.

At a distance from the center of the hub 10 from the radius of the hub 10 to 30% of the radius of the propeller 100, the maximum relative camber of the blade 20 is 5% ± 0.3%, and the maximum relative thickness of the blade 20 is 11% ± 0.5 %. In some embodiments, the maximum relative camber of the blade 20 is 5%, and the maximum relative thickness of the blade 20 is 11%. In some embodiments, the position of the maximum camber of the blade 20 is a chord length of 38.5% ± 0.5% from the leading edge 21. In some embodiments, the position of the maximum thickness of the paddle 20 is a chord length of 27.5% ± 0.5% from the leading edge.

From a position where the center of the hub 10 is 30% of the radius of the propeller 100 to 90% of the radius of the propeller 100, the maximum relative camber of the blade 20 is 5.8% ± 0.1%, and the maximum relative thickness of the blade 20 is 7.1 % ± 0.3%. In some embodiments, the maximum relative camber of the blade 20 is 5.8%, and the maximum relative thickness of the blade 20 is 7.1%. In some embodiments, the position of the maximum camber of the blade 20 is a chord length of 43.5% ± 0.3% from the leading edge. In some embodiments, the position of the maximum thickness of the blade 20 is a chord length of 21% ± 0.3% from the leading edge.

From a position where the center of the hub 10 is 90% of the radius of the propeller 100 to 100% of the radius of the propeller 100, the maximum relative camber of the blade 20 is 4.8% ± 0.1%, and the maximum relative thickness of the blade 20 is 5.1 % ± 0.3%. In some embodiments, the maximum relative camber of the blade 20 is 4.8%, and the maximum relative thickness of the blade 20 is 5.1%. In some embodiments, the position of the maximum camber of the blade 20 is a chord length 213.55% ± 0.3% from the leading edge. In some embodiments, the position of the maximum thickness of the blade 20 is a chord length 210.5% ± 0.3% from the leading edge.

Among them, the maximum relative camber of the blade 20 is the ratio of the maximum camber of the airfoil of the blade 20 to the chord length of the blade 20; the maximum relative thickness of the blade 20 is the maximum thickness of the airfoil of the blade 20 and the blade 20 Chord length ratio.

The horizontal distance between the leading edge 21 and the trailing edge 22 of the blade 20 increases from the root of the blade 20 to the blade tip of the blade 20 and then decreases, and the distance between the leading edge 21 and the trailing edge 22 at the blade tip The horizontal distance is smaller than the horizontal distance of the leading edge 21 and the trailing edge 22 at the root of the paddle.

It should be noted that the propeller 100 provided in this embodiment can be used to provide flying power for an unmanned aerial vehicle. During the operation of the propeller 100, based on the specific airfoil of the blade 20, the airflow velocity above the blade 20 is higher than that of the blade 20. The speed of the airflow below causes a pressure difference between the upper and lower sides of the paddle 20 to cause the UAV to generate upward power. The airfoil distribution of the blades 20 affects the aerodynamic efficiency of the propeller 100 and ultimately affects the flying performance of the unmanned aerial vehicle.

The maximum thickness of the blade 20 from the leading edge 21 refers to the distance between the position of the maximum thickness of the blade 20 and the leading edge 21, and the percentage of the distance to the chord length of the blade 20. Because the blades 20 of different structures have different chord lengths, this embodiment chooses this expression to use the chord length of the blades 20 as the limiting standard. When the chord length of the blades 20 changes, the limitation method still has High accuracy.

As a preferred embodiment, the specific airfoil distribution can be limited by the above numerical range. 5 and FIG. 6, wherein FIG. 5 is a cross-sectional view of the AA cross section of the propeller 100 in FIG. 2, and the AA position is a position point of the radius of the propeller 100 that is 15% from the center of the hub 10, FIG. 6 is a cross-sectional view of the BB cross section of the propeller 100, and the BB position is a position point of the radius of the propeller 100 at a distance of 30% from the center of the hub 10.

At a distance from the center of the hub 10 to the radius of the propeller 100 to the radius of the propeller 100, the maximum relative camber of the blade 20 is 5%, and the maximum relative thickness of the blade 20 is 11%. In one embodiment, the position of the maximum camber of the blade 20 is a chord length of 38.5% from the leading edge. In one embodiment, the position of the maximum thickness of the blade 20 is a chord length of 27.5% from the leading edge.

7 to FIG. 9, where FIG. 7 is a cross-sectional view of the C-C cross section of the propeller 100 in FIG. 2, and the C-C position is a point of the radius of the propeller 100 that is 50% from the center of the hub 10. FIG. 8 is a cross-sectional view of the D-D section of the propeller 100 in FIG. 2, and the D-D position is a position point of the radius of the propeller 100 which is 75% from the center of the hub 10. FIG. 9 is a cross-sectional view of the E-E cross section of the propeller 100 in FIG.

At a distance from the center of the hub 10 by a radius of the propeller 100 of 30% to a radius of the propeller 100 of 90%, the maximum relative camber of the blade 20 is 5.8%, and the maximum relative thickness of the blade 20 is 7.1%. In some embodiments, the position of the maximum camber of the blade 20 is a chord length of 43.5% from the leading edge. In some embodiments, the position of the maximum thickness of the blade 20 is a chord length 18% from the leading edge.

Referring to FIG. 10, FIG. 10 is a cross-sectional view of the F-F- section of the propeller 100 in FIG. 2, and the F-F position is a point from the center of the hub 10 to the radius of the propeller 100.

From a position where the radius of the propeller 100 from the center of the hub 10 is 90% to the radius of the propeller 100, the maximum relative camber of the blade 20 is 4.8%, and the maximum relative thickness of the blade 20 is 5.1%. In some embodiments, the position of the maximum camber of the blade 20 is a chord length 35.5% from the leading edge. In some embodiments, the position of the maximum thickness of the blade 20 is a chord length 30.5% from the leading edge.

Based on the above, as a preferred embodiment, the chord length of the blade 20 and the diameter of the propeller 100 are at a distance from the center of the hub 10 by a radius of the propeller 100 to 15% of the radius of the propeller 100. The ratio is 7% ± 0.5%.

At a distance from the center of the hub 10 by a radius of the propeller 100 of 30%, the ratio of the chord length of the blades 20 to the diameter of the propeller 100 is 8% ± 0.3%.

At a distance from the center of the hub 10 by a radius of the propeller 100 of 50%, the ratio of the chord length of the blades 20 to the diameter of the propeller 100 is 9.5% ± 0.1%.

At a distance from the center of the hub 10 to the radius of the propeller 100 by 75%, the ratio of the chord length of the blade 20 to the diameter of the propeller 100 is 7.6% ± 0.05%.

At a distance from the center of the hub 10 to the radius of the propeller 100 by 90%, the ratio of the chord length of the blade 20 to the diameter of the propeller 100 is 6.2% ± 0.05%.

At a distance from the center of the hub 10 to 100% of the radius of the propeller 100, the ratio of the chord length of the blade 20 to the diameter of the propeller 100 is 1.9% ± 0.05%.

It should be noted that based on the above description of FIGS. 5 to 10, 0% to 15% of the radius of the propeller 100 from the center of the hub 10 can be shown in FIG. 5, where the chord length of the blade 20 It can be C1 in the figure. The position from the center of the hub 10 to the radius of the propeller 100 by 30% can be shown in FIG. 6, where the chord length of the blade 20 can be C2 in the figure. The position from the radius of the propeller 100 which is 50% from the center of the hub 10 may be shown in FIG. 7, where the chord length of the blade 20 may be C3 in the figure. The position from the center of the hub 10 to the radius of the propeller 100 by 75% can be shown in FIG. 8, where the chord length of the blade 20 can be C4 in the figure. The position from the center of the hub 10 to the radius of the propeller 100 can be shown in FIG. 9, where the chord length of the blade 20 can be C5 in the figure. The position from the center of the hub 10 to the radius of the propeller 100 can be shown in FIG. 10, where the chord length of the blade 20 can be C6 in the figure.

Further, referring to FIG. 2, the planar shape of the blades 20 of the propeller 100 provided in this embodiment is “saber-shaped”, that is, the trailing edges 22 of the chord lengths of the blades 20 at different positions may be substantially straight. The line of the leading edge 21 is a smooth curve. At the same time, the horizontal distance between the leading edge 21 and the trailing edge 22 extends from the position of the blade root of the blade 20 to the position of the blade tip, and gradually shows a trend of first increasing and then decreasing, and the blade tip contracting backwards is obviously swept back. The shape, that is, the horizontal distance between the leading edge 21 and the trailing edge 22 at the blade tip position is smaller than the horizontal distance between the leading edge 21 and the trailing edge 22 at the blade root position. The smaller chord length setting at the blade tip can cut off the spread of air on the blade 20, thereby reducing the formation of the blade tip vortex or weakening the strength of the blade tip vortex, thereby reducing the rotation noise during the rotation of the propeller 100. It is possible to improve the flight safety of the unmanned aerial vehicle.

It should be noted that the above-mentioned values limit the characteristics of the saber-shaped blade 20 chord length provided in this embodiment, and the front edge 21 at the blade tip position is obviously swept back toward the rear edge 22. Such a setting is beneficial to reduce the propeller 100 The flow in the span direction further makes the distribution of the pulling force of the propeller 100 mainly concentrated at the position of the blade tip, thereby improving the aerodynamic efficiency of the propeller 100 and reducing the noise. In addition, a thin airfoil is selected for the entire propeller 100, so that the thickness noise of the propeller 100 can be reduced; a small chord length is arranged at the tip of the propeller, which is beneficial to reduce the vortex of the propeller 100 and thus reduce the noise caused by the propeller vortex interference. .

The radius of the propeller 100 may be the length shown in R in FIG. 2, that is, the length from the root of the blade 20 to the center of the circle of the hub 10, or may be half of the diameter L of the propeller 100. The maximum thickness of the blade 20 may be the length shown by T in FIG. 4, that is, a series of inscribed circles tangent to the upper and lower arcs are formed inside the airfoil of the blade 20, where the maximum inscribed The diameter of the circle is called the maximum thickness T of the blade. The chord length of the blade 20 may be the length shown in C in FIG. 4, that is, the length of the chord line 23, where the chord line 23 refers to the leading end 21 of the blade 20 at the leftmost end point on the section. The line connecting the trailing edge 22 to the rightmost endpoint on the section.

As a preferred embodiment, the plurality of paddles 20 are symmetrically disposed at the center of the hub 10.

It should be noted that the propeller 100 provided in this embodiment may include a plurality of blades 20, and each of the plurality of blades 20 is connected to the hub 10. Of course, the hub 10 and the blade 20 may be an integrated structure, or the blade 20 may be separately installed on the hub 10 to form a split-type propeller 100. For example, a mounting hole may be formed at the root position of the blade 20, Thus, the blade 20 is mounted on the hub 10 through the mounting hole. FIG. 2 and FIG. 3 of this embodiment show that the propeller 100 includes two blades 20 as an example. In actual use, the blades 20 on the hub 10 may be two, three, or more than three. In this embodiment, the number of specific blades 20 is not limited and is not limited to the above examples. The hub 10 drives a plurality of blades 20 to rotate to form a paddle.

In order to ensure the rotation stability of the propeller 100, a plurality of blades 20 may be symmetrically disposed on the hub 10 with the center line of the hub 10 as an axis center. In this way, when the hub 10 rotates, the different blades 20 form a relatively uniform lift to drive the unmanned aerial vehicle to fly smoothly.

It should be noted that the blade root described in this application refers to the part of the blade 20 near the hub 10, and the blade tip refers to the part of the blade 20 that is far from the hub 10.

It should be noted that the paddle blade 20 provided in this embodiment may be manufactured by using any material in the prior art, including but not limited to steel, aluminum alloy, plastic material, or carbon fiber. In manufacturing, various existing technologies such as molding, stamping, and forging can also be used.

Those skilled in the art can understand that the aerodynamic force generated by the blade root position of the blade 20 generates the maximum torque, so the blade root needs to select an airfoil with a large thickness to resist bending. The relative thickness defined in this embodiment is set at the blade tip. The small thickness airfoil can reduce the thickness noise of the propeller 100 and the blade tip vortex, thereby reducing the influence of the blade tip vortex on the rotation of the propeller 100 and achieving the effect of reducing noise.

The maximum camber of the blade 20 may be the length shown in F in FIG. 4, that is, the maximum distance between the middle arc line 24 and the chord line 23.

Further, at a distance of 0% to 15% of the radius of the propeller 100 from the center of the hub 10, the twist angle of the blade 20 is 16 ° ± 0.5 °.

At a distance from the center of the hub 10 to 30% of the radius of the propeller 100, the twist angle of the blade 20 is 20 ° ± 0.5 °.

At a distance from the center of the hub 10 to 50% of the radius of the propeller 100, the twist angle of the blade 20 is 15 ° ± 0.5 °.

At a distance from the center of the hub 10 to 75% of the radius of the propeller 100, the twist angle of the blade 20 is 13 ° ± 0.3 °.

At a distance from the center of the hub 10 to 85% of the radius of the propeller 100, the twist angle of the blade 20 is 10.5 ° ± 0.3 °.

At a distance from the center of the hub 10 to 100% of the radius of the propeller 100, the twist angle of the blade 20 is 10 ° ± 0.3 °.

It should be noted that the twist angle of the blade 20 is the angle between the chord line 23 of the blade 20 and the horizontal plane. Based on the above description of FIGS. 5 to 10, the distance from the center of the hub 10 to the radius of the propeller 100 from 0% to 15% can be shown in FIG. 5, where the twist angle of the blade 20 can be shown α1. The distance from the center of the hub 10 to 30% of the radius of the propeller 100 can be shown in FIG. 6, where the twist angle of the blade 20 can be α2 in the figure. The distance from the center of the hub 10 to 50% of the radius of the propeller 100 can be shown in FIG. 7, where the twist angle of the blade 20 can be α3 in the figure. The distance from the center of the hub 10 to 85% of the radius of the propeller 100 can be approximated as shown in FIG. 8, where the twist angle of the blade 20 can be α4 in the figure. The distance from the center of the hub 10 to 90% of the radius of the propeller 100 can be shown in FIG. 9, where the twist angle of the blade 20 can be α5 in the figure. The distance from the center of the hub 10 to 100% of the radius of the propeller 100 can be shown in FIG. 10, where the twist angle of the blade 20 can be α6 in the figure.

Further, the upper leaf surface, the lower leaf surface, and the edge surface of the leading edge 21 of the blade 20 are smooth curved surfaces, and the upper leaf surface, the lower leaf surface, and the edge surface of the leading edge 21 are smoothly transitioned. Further, the trailing edge 22 of the paddle blade 20 may be formed by comparing the upper blade surface and the lower blade surface with one point, and there may also be a certain distance extension between the upper blade surface and the lower blade surface.后 叶 22 of the paddle 20.

In the embodiment of the present application, the above technical solution is applicable to a propeller having a Reynolds number in a range of 10 ⁴ to 5 × 10 ⁵ .

The propellers provided in the embodiments of the present application, by setting specific airfoil distribution, twist angle distribution, and chord length distribution for the propeller blades, can ensure that the blades have better working performance, can effectively improve the aerodynamic efficiency of the propeller, and reduce its Noise level. Further, the application of the propeller to power components and unmanned aerial vehicles can correspondingly improve the efficiency of the power components and unmanned aerial vehicles, which can effectively extend the life of the unmanned aerial vehicle and reduce its noise level, and ultimately improve the unmanned aerial vehicle. Flight performance.

An embodiment of the present application further provides a power assembly, which includes a driving member and the propeller 100 in the foregoing embodiment, and a hub 10 of the propeller 100 is connected to the driving member.

It should be noted that the driving component in the power assembly provided in this embodiment may be a motor 31 or an engine, and the propeller hub 10 of the propeller 100 may be connected to the motor 31 or the output shaft of the engine, thereby outputting the rotational force of the motor 31 or the engine. It is transmitted to the blades through the hub 10, and the blades of the propeller 100 are driven to rotate around the centerline of the hub 10, and the airflow in the air is disturbed to generate lift or thrust, which drives the UAV to move.

The power assembly provided in this embodiment includes a motor and a propeller, and by setting specific airfoil distribution, twist angle distribution, and chord length distribution for the propeller blades, it can ensure that the blades have better working performance and can effectively improve the blade performance. The manufactured propeller has aerodynamic efficiency and endurance, and reduces its noise level. Further, the application of the propeller to the power component can correspondingly improve the efficiency of the power component and reduce its noise level, and finally improve the flightability of the unmanned aerial vehicle.

An embodiment of the present application further provides an unmanned aerial vehicle 40. It includes a fuselage 41, a boom 42 connected to the fuselage 41, and a power assembly 30 mounted on the boom 42 as described in the above embodiment.

It should be noted that the unmanned aerial vehicle 40 provided in this embodiment may be a two-axis unmanned aerial vehicle, a four-axis unmanned aerial vehicle, or an eight-axis unmanned aerial vehicle. This embodiment does not limit the specific types of unmanned aerial vehicles, and is not limited to the above examples.

The unmanned aerial vehicle provided in the third embodiment of the present application, by setting specific airfoil distribution, torsion angle distribution, and chord length distribution for the propeller blades in its power assembly, can ensure that the blades have better working performance and can effectively improve The propeller is aerodynamic and reduces its noise level. Further, the application of the propeller to power components and unmanned aerial vehicles can correspondingly improve the efficiency of the power components and unmanned aerial vehicles, which can effectively extend the life of the unmanned aerial vehicle and reduce its noise level, and ultimately improve the unmanned aerial vehicle. Flight performance.

In the description of this application, it should be understood that the terms "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", The orientation or positional relationship indicated by "outside" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the application and simplified description, and does not indicate or imply that the device or element referred to must have a specific orientation, Constructed and operated in a specific orientation, it should not be construed as a limitation on this application. In the description of the present application, the meaning of "plurality" is two or more, unless it is specifically specified otherwise.

The terms "including" and "having" and any variants thereof in the description and claims of the present application and the above-mentioned drawings are intended to cover non-exclusive inclusions, for example, processes, methods, including a series of steps or units, The system, product, or device need not be limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or inherent to these processes, methods, products, or devices.

Finally, it should be noted that the above embodiments are only used to describe the technical solution of the present application, rather than limiting it. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features can be replaced equivalently; and these modifications or replacements do not deviate the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present application. range.

Claims (17)

1. A propeller includes a propeller hub and a propeller blade connected to the propeller hub. The propeller blade includes an upper blade surface, a lower blade surface, a leading edge, and a trailing edge, and the leading edge and the trailing edge are located on the blade. On both sides, the leading edge and the trailing edge connect the upper blade surface and the lower blade surface. The radius of the hub is r and the radius of the propeller is R. It is characterized by:

   The maximum relative camber of the blade at a position r-30% × R from the center of the hub is 5% ± 0.3%;

   At a distance from the center of the hub of 30% × R to 90% × R, the maximum relative camber of the blade is 5.8% ± 0.1%;

   The maximum relative camber of the blade is at a position of 90% × R to 100% × R from the center of the hub; 4.8% ± 0.1%;

   The maximum relative camber of the blade is the ratio of the maximum camber of the airfoil of the blade to the chord length of the blade.
2. The propeller according to claim 1, wherein the maximum relative camber of the blade is 5% at a position r-30% x R from the center of the hub;

   The maximum relative camber of the blade at a position 30% × R to 90% × R from the center of the hub is 5.8%;

   At a distance from the center of the hub of 90% × R to 100% × R, the maximum relative camber of the blade is 4.8%.
3. The propeller according to claim 1 or 2, wherein:

   At a position r-30% × R from the center of the hub, the position of the maximum camber of the blade is a chord length of 38.5% ± 5% from the leading edge;

   At a position 30% × R ～ 90% × R from the center of the hub, the position of the maximum camber of the blade is a chord length 43.5% ± 0.3% from the leading edge;

   At a position 90% × R to 100% × R from the center of the hub, the maximum camber position of the blade is a chord length 35.5% ± 0.3% from the leading edge.
4. The propeller according to any one of claims 1 to 3, wherein:

   At a position r-30% × R from the center of the hub, the maximum relative thickness of the blade is 11% ± 0.5%;

   The maximum relative thickness of the paddle at a position 30% × R to 90% × R from the center of the hub is 7.1% ± 0.3%;

   At a position that is 90% × R to 100% × R from the center of the hub, the maximum relative thickness of the blade is 5.1% ± 0.3%;

   The maximum relative thickness of the blade is the ratio of the maximum thickness of the airfoil of the blade to the chord length of the blade.
5. The propeller according to claim 4, wherein:

   At a position r-30% × R from the center of the hub, the position of the maximum thickness of the blade is a chord length 27.5% ± 0.5% from the leading edge;

   At a position 30% × R ～ 90% × R from the center of the hub, the position of the maximum thickness of the blade is a chord length 18% ± 0.3% from the leading edge;

   At a position 90% × R to 100% × R from the center of the hub, the position of the maximum thickness of the blade is a chord length 30.5% ± 0.3% from the leading edge.
6. The propeller according to any one of claims 1 to 5, wherein:

   At a position 30% × R from the center of the hub, the twist angle of the blade is 20 ° ± 0.5 °;

   At a position 50% × R from the center of the hub, the twist angle of the blade is 15 ° ± 0.5 °;

   At a distance from the center of the hub to 75% of the radius of the propeller × R, the twist angle of the blade is 13 ° ± 0.3 °;

   At a distance from the center of the hub to 85% of the radius of the propeller × R, the twist angle of the blade is 10.5 ° ± 0.3 °;

   Wherein, the twist angle of the blade is the angle between the chord line of the blade and the horizontal plane.
7. The propeller according to claim 6, wherein:

   At a position from r to 15% × R from the center of the hub, the twist angle of the blade is 16 ° ± 0.5 °.
8. The propeller according to claim 6 or 7, wherein:

   At a position 100% × R from the center of the hub, the twist angle of the blade is 10 ° ± 0.3 °.
9. The propeller according to any one of claims 1 to 8, wherein:

   At a position r-30% × R from the center of the hub, the ratio of the chord length of the blade to the diameter of the propeller is 8% ± 0.3%;

   At a position 50% × R from the center of the hub, the ratio of the chord length of the blade to the diameter of the propeller is 9.5% ± 0.1%;

   At a position 75% × R from the center of the hub, the ratio of the chord length of the blade to the diameter of the propeller is 7.6% ± 0.05%;

   At a position 90% x R from the center of the hub, the ratio of the chord length of the blade to the diameter of the propeller is 6.2% ± 0.05%.
10. The propeller according to claim 9, wherein:

    At a position from r to 15% × R from the center of the hub, the ratio of the chord length of the blade to the diameter of the propeller is 7% ± 0.5%.
11. The propeller according to claim 9 or 10, wherein:

    At a position 100% × R from the center of the hub, the ratio of the chord length of the blade to the diameter of the propeller is 1.9% ± 0.05%.
12. The propeller according to any one of claims 1 to 11, wherein a trailing edge of the blade is linear.
13. The propeller according to any one of claims 1 to 12, wherein the upper blade surface, the lower blade surface, and the leading edge surface are all smooth curved surfaces, and the upper blade surface, The lower leaf surface and the edge surface of the leading edge and the edge surface of the trailing edge transition smoothly.
14. The propeller according to any one of claims 1 to 13, wherein a chord length of the blade is increased from a blade heel of the blade to a blade tip of the blade and then decreased, and The chord length of the blade tip of the blade is shorter than the chord length of the blade heel of the blade.
15. The propeller according to any one of claims 1 to 14, wherein the Reynolds number of the propeller ranges from 10 ⁴ to 5 × 10 ⁵ .
16. A power assembly, comprising a motor and the propeller according to any one of claims 1 to 15, and a hub of the propeller is connected to an output shaft of the motor.
17. An unmanned aerial vehicle, comprising a fuselage, an airframe connected to the airframe, and the power assembly according to claim 16 mounted on the airframe.

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