CN110896626A

CN110896626A - Screw, power component and aircraft

Info

Publication number: CN110896626A
Application number: CN201880016249.8A
Authority: CN
Inventors: 林家靖; 陈鹏; 梁阔
Original assignee: SZ DJI Technology Co Ltd
Current assignee: SZ DJI Technology Co Ltd
Priority date: 2018-05-25
Filing date: 2018-09-25
Publication date: 2020-03-20
Also published as: WO2019223205A1; CN208291466U

Abstract

The embodiment of the invention discloses a propeller (100), a power assembly (200) and an aircraft (1000). The propeller (100) comprises a hub (10) and blades (20), wherein the blades (20) are connected to the hub (10). The paddle (20) comprises a paddle root (21), a paddle tip (22) deviating from the paddle root (21), a pressure surface (23) and a suction surface (24) opposite to the pressure surface (23). The blade tip (22) extends obliquely towards the side of the pressure surface (23) along the span direction of the blade (20). The distance between a horizontal plane where the airfoil-shaped rotation center of the blade (20) is located and the center of the hub (10) is 50% of the radius of the propeller (100) is 3.0% to 9.3% of the radius of the propeller (100) at a position where the distance from the center of the hub (10) is 100% of the radius of the propeller (100); therefore, the blades (20) with specific shapes are defined by the parameters, and the propeller (100) adopting the blades (20) can reduce the air resistance of the propeller (100), improve the pulling force and the efficiency, increase the secondary flight distance of the aircraft (1000) to improve the flight performance of the aircraft (1000) on one hand, and reduce the noise generated by the blades (20) in work on the other hand, so that the aircraft (1000) is quieter when hovering, and the user experience is improved.

Description

Screw, power component and aircraft

Technical Field

The invention relates to the field of aircrafts, in particular to a propeller, a power assembly and an aircraft.

Background

Propellers on aircraft, which are important key components of aircraft, are used to convert the rotation of a rotating shaft in a motor or an engine into thrust or lift. The turbulence of the blade sections and the impingement of the downwash air on the aircraft skin structure during rotation of prior art propellers can produce loud noise. The noise of the aircraft, the motor noise and the structural vibration noise are often superposed together, and the noise of certain frequency bands is amplified, so that the overall noise of the aircraft is high, and the use experience is poor.

Disclosure of Invention

The embodiment of the invention provides a propeller, a power assembly and an aircraft.

A propeller of an embodiment of the present invention comprises a hub and blades attached to the hub, wherein: the paddle comprises a paddle root, a paddle tip, a pressure surface and a suction surface, wherein the paddle tip is deviated from the paddle root; the blade tip extends towards one side of the pressure surface along the spanwise direction of the blade in an inclined mode; the distance between a horizontal plane in which the airfoil-shaped rotation center of the blade is located and a horizontal plane in which the airfoil-shaped rotation center of the blade is located at a position that is located at a distance of 100% of the radius of the propeller from the center of the hub and a horizontal plane in which the airfoil-shaped rotation center of the blade is located at a distance of 50% of the radius of the propeller from the center of the hub is 3.0% to 9.3% of the radius of the propeller.

In some embodiments, the distance between a horizontal plane at which the centre of rotation of the airfoil of the blade lies and a horizontal plane at which the centre of rotation of the airfoil of the blade lies at 50% of the radius of the propeller from the centre of the hub is from 2.6% to 7.0% of the radius of the propeller at 97.9% of the radius of the propeller from the centre of the hub; and/or

The distance between a horizontal plane where the airfoil rotation center of the blade is located and a horizontal plane where the airfoil rotation center of the blade is located at a distance of 95.8% of the radius of the propeller from the center of the hub and a horizontal plane where the airfoil rotation center of the blade is located at a distance of 50% of the radius of the propeller from the center of the hub is 1.4% to 5.4% of the radius of the propeller; and/or

The distance between a horizontal plane where the airfoil rotation center of the blade is located and a horizontal plane where the airfoil rotation center of the blade is located at a distance of 93.8% of the radius of the propeller from the center of the hub and a horizontal plane where the airfoil rotation center of the blade is located at a distance of 50% of the radius of the propeller from the center of the hub is 1.1% to 3.2% of the radius of the propeller; and/or

The distance between a horizontal plane where the airfoil rotation center of the blade is located and a horizontal plane where the airfoil rotation center of the blade is located at a distance of 91.7% of the radius of the propeller from the center of the hub and a horizontal plane where the airfoil rotation center of the blade is located at a distance of 50% of the radius of the propeller from the center of the hub is 0.2% to 2.1% of the radius of the propeller; and/or

The distance between a horizontal plane where the airfoil rotation center of the blade is located and a horizontal plane where the airfoil rotation center of the blade is located at a position 50% of the radius of the propeller from the center of the hub is 0.2% to 0.6% of the radius of the propeller at a position 89.2% of the radius of the propeller from the center of the hub; and/or

The distance between a horizontal plane in which the airfoil rotation center of the blade is located and a horizontal plane in which the airfoil rotation center of the blade is located at a distance of 87.5% of the radius of the propeller from the center of the hub and a horizontal plane in which the airfoil rotation center of the blade is located at a distance of 50% of the radius of the propeller from the center of the hub is 0.02% to 0.04% of the radius of the propeller; and/or

The distance between a horizontal plane where the airfoil rotation center of the blade is located and a horizontal plane where the airfoil rotation center of the blade is located at a position which is 120mm away from the center of the hub and is 50% of the radius of the propeller from the center of the hub is 7.00mm +/-3 mm; and/or

The distance between the horizontal plane where the airfoil rotation center of the blade is located and the horizontal plane where the airfoil rotation center of the blade is located at the position which is 50% of the radius of the propeller from the center of the hub is 5.40mm +/-3 mm at 117.5mm from the center of the hub; and/or

The distance between the horizontal plane of the airfoil rotation center of the blade at a position 115mm away from the center of the hub and the horizontal plane of the airfoil rotation center of the blade at a position 50% of the radius of the propeller away from the center of the hub is 3.86mm +/-2 mm; and/or

The distance between the horizontal plane of the airfoil rotation center of the blade at 112.5mm from the center of the hub and the horizontal plane of the airfoil rotation center of the blade at 50% of the radius of the propeller from the center of the hub is 2.46mm +/-1 mm; and/or

At a distance of 110mm from the center of the hub, the distance between the horizontal plane of the airfoil rotation center of the blade and the horizontal plane of the airfoil rotation center of the blade at a distance of 50% of the radius of the propeller from the center of the hub is 1.29mm +/-1 mm; and/or

The distance between the horizontal plane where the airfoil rotation center of the blade is located and the horizontal plane where the airfoil rotation center of the blade is located at the position which is at a distance of 107.5mm from the center of the hub and is at 50% of the radius of the propeller from the center of the hub is 0.45mm +/-0.2 mm; and/or

And at a distance of 105mm from the center of the hub, the distance between the horizontal plane where the airfoil rotation center of the blade is located and the horizontal plane where the airfoil rotation center of the blade is located at a distance of 50% of the radius of the propeller from the center of the hub is 0.03mm +/-0.01 mm.

In certain embodiments, the angle of attack of the blades is 17.50 ° ± 2.5 ° at a distance from the center of the hub of 41.7% of the radius of the propeller; and/or

The angle of attack of the blades is 16.54 ° ± 2.5 ° at a distance from the centre of the hub of 50% of the radius of the propeller; and/or

At 58.3% of the radius of the propeller from the center of the hub, the angle of attack of the blades is 15.45 ° ± 2.5 °; and/or

At 66.7% of the radius of the propeller from the center of the hub, the angle of attack of the blades is 14.25 ° ± 2.5 °; and/or

The angle of attack of the blades is 12.97 ° ± 2.5 ° at a distance from the center of the hub of 75% of the radius of the propeller.

In certain embodiments, the angle of attack of the blades is 18.95 ° ± 2.5 ° at a distance from the center of the hub of 25% of the radius of the propeller; and/or

At 33.3% of the radius of the propeller from the center of the hub, the angle of attack of the blades is 18.38 ° ± 2.5 °; and/or

The angle of attack of the blades is 11.49 ° ± 2.5 ° at 83.3% of the radius of the propeller from the center of the hub; and/or

The angle of attack of the blades is 9.47 ° ± 2.5 ° at 91.7% of the radius of the propeller from the center of the hub; and/or

The angle of attack of the blades is 5.94 ° ± 2.5 ° at a distance from the centre of the hub of 100% of the radius of the propeller; and/or

At 30mm from the centre of the hub, the angle of attack of the blade is 18.95 °; and/or

At 40mm from the centre of the hub, the angle of attack of the blade is 18.38 °; and/or

At 50mm from the centre of the hub, the angle of attack of the blade is 17.50 °; and/or

At 60mm from the centre of the hub, the angle of attack of the blade is 16.54 °; and/or

At 70mm from the centre of the hub, the angle of attack of the blade is 15.45 °; and/or

At 80mm from the centre of the hub, the angle of attack of the blade is 14.25 °; and/or

At 90mm from the center of the hub, the angle of attack of the blade is 12.97 °; and/or

At 100mm from the centre of the hub, the angle of attack of the blade is 11.49 °; and/or

At 110mm from the centre of the hub, the angle of attack of the blade is 9.47 °; and/or the angle of attack of the blades is 5.94 ° at 120mm from the centre of the hub.

In some embodiments, the chord length of the blade is 29.80mm ± 5mm at 41.7% of the radius of the propeller from the center of the hub; and/or

The chord length of the blade is 28.54mm + -5 mm at a distance of 50% of the radius of the propeller from the center of the hub; and/or

The chord length of the blade is 27.27mm ± 5mm at 58.3% of the radius of the propeller from the centre of the hub; and/or

The chord length of the blade is 25.98mm ± 5mm at 66.7% of the radius of the propeller from the centre of the hub; and/or

The chord length of the blade is 24.71mm ± 5mm at a distance of 75% of the radius of the propeller from the centre of the hub.

In some embodiments, the chord length of the blade is 32.01mm ± 5mm at a distance of 25% of the radius of the propeller from the center of the hub; and/or

The chord length of the blade is 31.05mm + -5 mm at a distance of 33.3% of the radius of the propeller from the center of the hub; and/or

The chord length of the blade is 21.48mm ± 5mm at a distance of 83.3% of the radius of the propeller from the center of the hub; and/or

The chord length of the blade is 15.40mm + -5 mm at a distance of 91.7% of the radius of the propeller from the center of the hub; and/or

The chord length of the blade is 3.61mm ± 2mm at a distance from the centre of the hub of 100% of the radius of the propeller.

At 30mm from the centre of the hub, the chord length of the blade is 32.01 mm; and/or

The chord length of the blade is 31.05mm at 40mm from the centre of the hub; and/or

At 50mm from the centre of the hub, the chord length of the blade is 29.80 mm; and/or

At 60mm from the centre of the hub, the chord length of the blade is 28.54 mm; and/or

At 70mm from the centre of the hub, the chord length of the blade is 27.27 mm; and/or

At 80mm from the centre of the hub, the chord length of the blade is 25.98 mm; and/or

The chord length of the blade is 24.71mm at 90mm from the centre of the hub; and/or

At 100mm from the centre of the hub, the chord length of the blade is 21.48 mm; and/or

At 110mm from the centre of the hub, the chord length of the blade is 15.40 mm; and/or

The chord length of the blade is 3.61mm at 120mm from the centre of the hub.

In certain embodiments, the diameter of the propeller is 240mm ± 24 mm; and/or the pitch of the blade is 5.36 plus or minus 0.5 inches.

In some embodiments, the blade further comprises a leading edge connected to one side of the pressure surface and the suction surface, a trailing edge connected to the other side of the pressure surface and the suction surface, and a swept back portion formed at the tip of the blade, the swept back portion extending obliquely from the leading edge to the trailing edge; and/or

The rear edge is convexly provided with a curved rear edge arch part close to the paddle root.

In some embodiments, the blade forms a return bend at the tip, the leading edge extends obliquely from the return bend along the span of the blade towards the side on which the pressure surface is located, the sweep extends obliquely from the return bend from the leading edge towards the trailing edge, and the return bend is 87.5% of the radius of the propeller from the centre of the hub.

In some embodiments, the number of blades is at least two, and at least two of the blades are attached to the hub and are centrosymmetric about the center of the hub; and/or

The blade having a central axis passing through the center of the hub, the leading edge having a leading edge tangent parallel to the central axis, the trailing edge having a trailing edge tangent parallel to the central axis, the sweep being located between the leading edge tangent and the trailing edge tangent; and/or

The suction surface and the pressure surface are both curved surfaces.

The power assembly of the embodiment of the invention comprises a driving piece and the propeller of any one of the above embodiments, wherein the propeller is connected with the driving piece through the propeller hub.

In certain embodiments, the drive member is an electric motor having KV values of 720 ± 72 revolutions/(min-volt).

The aircraft of the embodiment of the invention comprises a fuselage and the power assembly of any one of the above embodiments, wherein the power assembly is connected with the fuselage.

In some embodiments, the aircraft includes a plurality of power assemblies that rotate in different directions, and the aircraft is a multi-rotor aircraft.

According to the propeller, the power assembly and the aircraft provided by the embodiment of the invention, the tip of the propeller extends obliquely towards one side of the pressure surface along the span direction of the propeller blade, and the distance between the horizontal plane where the airfoil-shaped rotating center of the propeller blade is located and the center of the propeller hub is 50% of the radius of the propeller blade is 3.0-9.3% of the radius of the propeller blade at the position where the center of the propeller blade is located; therefore, the propeller with the specific shape is defined by the parameters, on one hand, the propeller with the propeller can reduce the air resistance of the propeller, improve the pulling force and the efficiency, increase the secondary flight distance of the aircraft so as to improve the flight performance of the aircraft, and on the other hand, the propeller can reduce the noise generated by the propeller during working, so that the aircraft is quieter when hovering, and the user experience is improved.

Additional aspects and advantages of embodiments of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of embodiments of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which: newly-added figure modification, illustration in description

Fig. 1 is a perspective view of a propeller according to an embodiment of the present invention.

Fig. 2 is a schematic plan view of a propeller according to an embodiment of the present invention.

Fig. 3 is a schematic plan view of a propeller according to an embodiment of the present invention.

Fig. 4 is a schematic plan view of a propeller according to an embodiment of the present invention.

FIG. 5 is a schematic diagram of frequency response curves of the propeller of the present invention and the existing propeller I and propeller II under the same test conditions of hovering condition acoustic performance.

Fig. 6 is a schematic coordinate diagram of a rotation center of an airfoil of a blade provided by an embodiment of the invention.

Fig. 7 is a schematic plan view of the tip in the propeller of the embodiment shown in fig. 4.

Fig. 8 is a cross-sectional view of the section K-K at 15mm from the free end of the propeller of the embodiment shown in fig. 7.

Figure 9 is a cross-sectional view of the O-O section at 12.5mm from the free end of the propeller of the embodiment shown in figure 7.

Fig. 10 is a cross-sectional view of the L-L section at 10mm from the free end of the propeller of the embodiment shown in fig. 7.

Figure 11 is a cross-sectional view of the section P-P at 7.5mm from the free end of the propeller of the embodiment shown in figure 7.

Fig. 12 is a cross-sectional view of the section N-N at 5mm from the free end of the propeller of the embodiment shown in fig. 7.

Fig. 13 is a cross-sectional view of the section Q-Q at 2.5mm from the free end of the propeller of the embodiment shown in fig. 7.

Figure 14 is a cross-sectional view of section a-a at 30mm from the hub center in the propeller of the embodiment shown in figure 4.

Figure 15 is a cross-sectional view of the section B-B in the propeller of the embodiment shown in figure 4 at 40mm from the centre of the hub.

Figure 16 is a cross-sectional view of the C-C section at 50mm from the center of the hub in the propeller of the embodiment shown in figure 4.

Figure 17 is a cross-sectional view of the D-D section at 60mm from the center of the hub in the propeller of the embodiment shown in figure 4.

Figure 18 is a cross-sectional view of the section E-E in the propeller of the embodiment shown in figure 4 at 70mm from the centre of the hub.

Figure 19 is a cross-sectional view of the F-F section at 80mm from the center of the hub in the propeller of the embodiment shown in figure 4.

Figure 20 is a cross-sectional view of the G-G section in the propeller of the embodiment shown in figure 4 at 90mm from the center of the hub.

Figure 21 is a cross-sectional view of the section H-H at 100mm from the hub centre in the propeller of the embodiment shown in figure 4.

Figure 22 is a cross-sectional view of the section I-I at 110mm from the hub centre in the propeller of the embodiment shown in figure 4.

Figure 23 is a cross-sectional view of the J-J section at 120mm from the hub center of the propeller of the embodiment shown in figure 4.

Fig. 24 is a schematic plan view of an aircraft according to an embodiment of the invention.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the invention, as detailed in the appended claims.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in this specification and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

It is to be understood that although the terms first, second, third, etc. may be used herein to describe various information, these information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, first information may also be referred to as second information, and similarly, second information may also be referred to as first information, without departing from the scope of the present invention. The word "if" as used herein may be interpreted as "at … …" or "when … …" or "in response to a determination", depending on the context.

The terms upper, lower, etc. are used in this embodiment with reference to the propeller after it is mounted on the aircraft and to the normal operating attitude of the aircraft and should not be considered limiting.

The propeller, the power assembly and the aircraft according to the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The features of the following examples and embodiments may be combined with each other without conflict.

Referring to fig. 1 to 4, an embodiment of the present invention provides a propeller 100, where the propeller 100 includes a hub 10 and blades 20. Blades 20 are attached to hub 10. Blade 20 includes a root 21, a tip 22 facing away from root 21, a pressure surface 23, and a suction surface 24 opposite pressure surface 23. The tip 22 extends obliquely in the span direction of the blade 20 towards the side on which the pressure surface 23 is located. The distance between a horizontal plane on which the airfoil rotation center of the blade 20 is located at a distance of 100% of the radius of the propeller 100 from the center of the hub 10 and a horizontal plane on which the airfoil rotation center of the blade 20 is located at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 3.0% to 9.3% of the radius of the propeller 100. The hub 10 may be cylindrical, or the cross section of the hub 10 may be elliptical, rhombic, or the like. The center of the propeller hub 10 is provided with a connecting hole which is used for being sleeved on the output end of the motor. The blades 20 may be elongated, with the blades 20 extending radially of the hub 10. Pressure side 23 is the surface of blade 20 that faces the ground during normal flight of aircraft 1000, and suction side 24 is the surface of blade 20 that faces the sky during normal flight of aircraft 1000.

In the propeller 100 of the embodiment of the present invention, since the tip 22 extends obliquely along the span direction of the blade 20 toward the side where the pressure surface 23 is located, and the distance between the horizontal plane where the airfoil rotation center of the blade 20 is located and the horizontal plane where the airfoil rotation center of the blade 20 is located at the position 50% of the radius of the propeller 100 from the center of the hub 10 is 3.0% to 9.3% of the radius of the propeller 100 at the position 100% of the radius of the propeller 100 from the center of the hub 10, the blade 20 having a specific shape is defined by the above parameters, and thus the propeller 100 using the blade 20 can reduce the air resistance of the propeller 100, improve the drag and efficiency, increase the cruising distance of the aircraft 1000 (shown in fig. 24) to improve the flight performance of the aircraft 1000, and reduce the noise generated by the blade 20 during operation to make the aircraft 1000 quieter when hovering, the user experience is improved.

Referring to table 1, a comparison between the test results of the propeller 100 provided in the present embodiment and the existing propeller i shows that, as shown in table 1, the power of the propeller 100 provided in the present embodiment is lower under the same pulling force, that is: under the condition of lower power, the pull force is larger, so that the electric quantity loss is reduced, and the cruising distance is increased. Therefore, the propeller 100 provided by the embodiment can significantly improve the pulling force, ensure sufficient power and prolong the endurance time and improve the flight performance under the extreme condition of large takeoff weight in a high altitude area or a low altitude area with reduced density.

TABLE 1

Referring to fig. 5, the propeller 100 of the present embodiment is compared with the test results of the two existing propellers (propeller one and propeller two). As can be seen from the frequency response curve (frequency (hz) -loud (dB-a)) in fig. 5, under the same hovering condition acoustic performance test condition, the noise generated by the propeller 100 provided by the present embodiment is compared with the noise generated by the two existing propellers, and under the same high frequency condition, the Loudness of the propeller 100 provided by the present embodiment is significantly lower than the Loudness of the two existing propellers. Therefore, the propeller 100 provided by the embodiment can effectively reduce high-frequency noise, reduce discomfort of human ears caused by the high-frequency noise, and improve user experience. In addition, the propeller 100 provided in the present embodiment can be applied to scenes with high requirements for sound, such as reconnaissance and aerial photography (recording images and audio during aerial photography).

With continued reference to fig. 1-4, in the present embodiment, optionally, the suction surface 24 and the pressure surface 23 are both curved surfaces. The suction surface 24 and the pressure surface 23 are curved aerodynamic profiles that prevent turbulence generated by the various portions of the blades 20 and downwash from directly impacting the fuselage 50 of the aircraft 1000 (as shown in fig. 24), thereby reducing the overall noise of the aircraft 1000.

In this embodiment, the blade 20 further includes a front edge 25 connected to one side of the pressure surface 23 and the suction surface 24, a rear edge 26 connected to the other side of the pressure surface 23 and the suction surface 24, and a swept back portion 221 formed at the tip 22, wherein the swept back portion 221 extends obliquely from the front edge 25 to the rear edge 26. This has the effect of further improving the pulling force and efficiency of the propeller 100.

In this embodiment, optionally, the blade 20 forms a return bend 27 at the position of the blade tip 22, the leading edge 25 extends obliquely from the return bend 27 along the span of the blade 20 toward the side where the pressure surface 23 is located, and the sweep portion 221 extends obliquely from the return bend 27 from the leading edge 25 toward the trailing edge 26. The position of the return bend 27 is indicated by MM.

In this embodiment, the return bend 27 is optionally 87.5% of the radius of the propeller 100 from the center of the hub 10. The return bend 27 is located away from the center of the hub 10, improving the aesthetic appearance of the blades 20 and also reducing the interaction between the propeller 100 and the horn 40 (shown in fig. 24) of the aircraft 1000.

In this embodiment, the rear edge 26 is optionally convexly formed with a curved rear edge bulge 261 adjacent to the blade root 21. The curved shape of the trailing edge camber 231 further enhances the drag of the blade 20.

In the present embodiment, at least two blades 20 are optionally provided, and at least two blades 20 are connected to the hub 10 and are centrosymmetric with respect to the center of the hub 10. This improves the balance of the propeller 100.

In this embodiment, optionally, blade 20 has a central axis N-N (see FIG. 4) passing through the center of hub 10, leading edge 25 has a leading edge tangent O-O parallel to central axis N-N, trailing edge 26 has a trailing edge tangent P-P parallel to central axis N-N, and sweep 221 is located between leading edge tangent O-O and trailing edge tangent P-P. The swept back portion 221 can thereby reduce turbulence and downwash generated by the blades 20, thereby reducing turbulence and downwash hitting the fuselage 50 of the aircraft 1000, reducing the air resistance of the propeller 100, improving maneuverability of the aircraft 1000, making the aircraft 1000 more stable, and further reducing the overall noise of the aircraft 1000.

Referring to fig. 1, in the present embodiment, the blade tip 22 extends obliquely along the span direction of the blade 20 toward the side where the suction surface 24 is located, and the swept back portion 221 extends obliquely from the leading edge 25 toward the trailing edge 26. Specifically, as shown in fig. 1, a right-hand rectangular coordinate system O ' -X ' Y ' Z ' is established on the propeller 100, with the center O ' of the coordinate system located at the center of the hub 10. Referring to fig. 6, a right-handed rectangular coordinate system O-XYZ is established on the airfoil of the blade 20, a center O of the coordinate system is located at an airfoil rotation center of a first airfoil (the first airfoil is a virtual airfoil when the blade 20 is designed) of the blade 20, a center of the hub 10 is located on a plane of the first airfoil, and an X-axis of the airfoil of the blade 20 is defined as: the starting point is a circle center O, and the extending direction of the propeller 100 along the blades 20 is the positive direction of the X axis; the Y-axis of the airfoil of blade 20 is defined as: the starting point is the center of a circle O, the thumb points to the X axis, and the direction pointed by the index finger is the positive direction of the Y axis; the Z-axis of the airfoil of blade 20 is defined as: the starting point is the center of a circle O, the thumb points to the X axis, and the middle finger points to the positive direction of the Z axis. The circle center O (the airfoil rotation center of the first airfoil) is obtained by referring to fig. 1 and 6 together, and assuming that fig. 6 is the first airfoil of the blade 20, the value of X 'of the plane of the first airfoil in the coordinate system O' -X 'Y' Z 'is known, in other words, the value of X of the circle center O in the coordinate system O' -X 'Y' Z 'is known, that is, X' O is known; subtracting the minimum value Y ' min from the maximum value Y ' max of the plane where the first airfoil is located in the coordinate system O ' -X ' Y ' Z ', and dividing the minimum value Y ' min by 3, wherein the coordinate added with the minimum value Y ' min is the Y ' value of the circle center O in the coordinate system O ' -X ' Y ' Z ', namely Y ' O ═ Y ' max-Y ' min)/3+ Y ' min; subtracting the minimum value Z ' min from the maximum value Z ' max of the plane where the first airfoil is located in the coordinate system O ' -X ' Y ' Z ', and dividing the minimum value Z ' min by 2, wherein the coordinate added with the minimum value Z ' min is the Z ' value of the circle center O in the coordinate system O ' -X ' Y ' Z ', namely, Z ' O is (Z ' max-Z ' min)/2+ Z ' min; thus, the position (X ' O, Y ' O, Z ' O) of the center O in the coordinate system O ' -X ' Y ' Z ' is determined, and a right-handed rectangular coordinate system O-XYZ can be established with the center O as the center. After the right-hand rectangular coordinate system O-XYZ is established, the subsequent rotation centers of other airfoils can be calculated according to the method to obtain corresponding coordinates in the right-hand rectangular coordinate system O-XYZ, which is not described herein again. Wherein the horizontal plane in which the centre of rotation of the airfoil of the blade 20 lies coincides with the plane XOY at a distance of 50% of the radius of the propeller 100 from the centre of the hub 10.

Referring to table 2, Blade Radius (mm) indicates the X-axis coordinate position of the airfoil rotation center of Blade 20 in the coordinate system O-XYZ (where, circle center O and circle center O ' are located in the same vertical plane, and the distance between the airfoil rotation center of each airfoil and circle center O is the same as the distance between each airfoil and center O ' of hub 10), so the airfoil rotation center of Blade 20 is also the X ' -axis coordinate position in the coordinate system O ' -X ' Y ' Z ', starting with the airfoil rotation center of the virtual airfoil at center O ' of hub 10, at which the distance from the center O ' of hub 10 is 0mm, and ending with the airfoil rotation center of Blade 20 farthest from center O ' of hub 10, at which the distance from the center O ' of hub 10 is 120 mm. The term "horizontal Length (mm)" indicates the Z-axis coordinate position of the airfoil center of rotation of the blade 20 in the coordinate system O-XYZ, wherein positive values of horizontal Length (mm) indicate the blade 20 up-reflection and negative values indicate the blade 20 down-reflection. Sweet Length (mm) represents the Y-axis coordinate position of the airfoil center of rotation of blade 20 in coordinate system O-XYZ, where positive values of sweet Length (mm) indicate forward Sweep of blade 20 and negative values indicate aft Sweep of blade 20. For example, for an airfoil having a distance of 5mm from the center O' of the hub 10, the airfoil rotation center has a Z value of 0 and a Y value of 0 in O-XYZ, indicating that the airfoil is neither up-swept nor back-swept; for an airfoil having a distance of 105mm from the center O' of hub 10, the airfoil center of rotation in O-XYZ has a Z value of-0.03 mm and a Y value of-0.07 mm, indicating that the airfoil is down-swept and back-swept.

TABLE 2

As can be seen from table 2, when the distance of the blade 20 from the center of the hub 10 is 105mm, i.e., the return bend 27 is 87.5% of the radius of the propeller 100 from the center of the hub 10, the sweep-back portion 221 extends obliquely from the return bend 27 from the leading edge 25 to the trailing edge 26, i.e., the sweep-back is started when the distance of the blade 20 from the center of the hub 10 is 105 mm. When the plurality of blades 20 are simultaneously operated, the sweepback portion 221 regularly extends obliquely from the front edge 25 to the rear edge 26 from the return bend 27, so that turbulence and downwash generated by interaction of the plurality of blades 20 can be reduced, turbulence and downwash hitting the fuselage 50 of the aircraft 1000 can be reduced, air resistance to the blades 20 can be reduced, the pulling force and efficiency of the propeller 100 can be further improved, the maneuverability of the aircraft 1000 can be improved, the aircraft 1000 can be more stable, and noise generated by impact of the turbulence and downwash on the fuselage 50 of the aircraft 1000 can be further reduced.

As can be seen from table 2, when the distance from the blade 20 to the center of the hub 10 is 105mm, i.e. the distance from the return bend 27 to the center of the hub 10 is 87.5% of the radius of the propeller 100, the leading edge 25 extends obliquely from the return bend 27 along the span of the blade 20 toward the side where the pressure surface 23 is located, i.e. starts to face backwards when the distance from the blade 20 to the center of the hub 10 is 105 mm. When the plurality of blades 20 are simultaneously operated, the leading edge 25 regularly extends obliquely from the inflection point 27 along the side of the blade 20 where the pressure surface 23 is located in the span direction, so that turbulence and downwash generated by interaction of the plurality of blades 20 can be reduced, turbulence and downwash on the horn 40 and the fuselage 50 of the aircraft 1000 can be reduced, in addition, the lifting point of the blade 20 can be rated, the flight attitude of the aircraft 1000 can be automatically corrected, the inertial stability of the aircraft 1000 is increased, the aircraft 1000 can fly more stably, and noise generated by impact of the turbulence and the downwash on the fuselage 50 of the aircraft 1000 is further reduced.

Referring also to fig. 7-13, in this embodiment, the swept back portion 221 extends obliquely from the leading edge 25 to the trailing edge 26 starting at the return bend 27, and the distance from the center of the hub 10 at the return bend 27 is 87.5% of the radius of the propeller 100. Specifically, the sectional shape and parameters of the swept-back portion 221 are as follows:

referring to fig. 8, in the present embodiment, optionally, the diameter of the propeller 100 is 240mm ± 24mm, when the distance between the blade 20 and the free end 222 is 15mm, that is, the distance between the blade 20 and the center of the hub 10 is 105mm, that is, when the distance between the blade 20 and the center of the propeller 100 is 87.5% of the radius D11 from the center of the hub 10, the distance between the horizontal plane on which the airfoil rotation center of the blade 20 is located and the center of the propeller 100 is 50% of the radius of the propeller 100 is 0.03mm ± 0.01mm, the angle of attack α of the blade 20 is 10.52 ° ± 2.5 °, the chord length L11 of the blade 20 is 18.71mm ± 5mm, so as to further reduce the air resistance of the propeller 100, improve the drag force and efficiency, and reduce the noise, wherein the distance between the two horizontal planes may be 0.02mm, 0.03mm, 0.04mm, 0.02mm, 71mm, 13.0313.71 mm, 13.71mm, 13.02 mm, 13.71mm, 14.19 mm, 13.19 mm, 14.19 mm, 14 mm, 14.19 mm, 14.5 mm, 14.02 mm, 14 mm, 14.02 mm, 14.19 mm, 14.5 mm, 14 mm, 14.02 mm, 14.5 mm, 14.02 mm, 14.19 mm, 13.5 mm, 14.19 mm, 14.5 mm, 13.9.9.9.9.9.5 mm, 14.9.9.9.9.9 mm, 14.9.9 mm, 14.9.9.5 mm, 14 mm, 14.9.9.9.9.9 mm, 14.9.9 mm, 14 mm, or 13.9.

Referring to fig. 9, in the present embodiment, optionally, the diameter of the propeller 100 is 240mm ± 24mm, when the distance between the blade 20 and the free end 222 is 12.5mm, that is, the distance between the blade 20 and the center of the hub 10 is 107.5mm, that is, when the distance between the blade 20 and the center of the propeller 100 is D12 at 89.2% D11, the distance between the horizontal plane on which the airfoil rotation center of the blade 20 is located and the horizontal plane on which the airfoil rotation center of the blade 20 is located at 50% of the radius of the propeller 100 from the center of the hub 10 is 0.45mm ± 0.2mm, the angle of attack α of the blade 20 is 9.95 ° ± 2.5mm, and the chord length L12 of the blade 20 is 17.10mm ± 5mm, so as to further reduce the air resistance of the propeller 100, improve the efficiency and reduce the noise, and the angle of attack may be any one of 0.25mm, 0.45mm, 0.65mm, 0.29mm, 0.34.34 mm, 0.34mm, 0.42mm, 10.45 mm, 10.9 mm, 10mm, 10.5 mm, 10mm, 10.9.9 mm, 10mm, 10.9.9.9.9 mm, 10mm, 10.9.9.9 mm, 10mm, 10.9.9.9.5 mm, 10 mm.

Referring to fig. 10, in the present embodiment, optionally, when the diameter of the propeller 100 is 240mm ± 24mm, and the distance between the blade 20 and the free end 222 is 10mm, that is, the distance between the blade 20 and the center of the hub 10 is 110mm, that is, when the distance is 91.7% D13% of the radius of the propeller 100 from the center of the hub 10, that is, the distance between a horizontal plane in which the airfoil rotation center of the blade 20 is located and 50% of the radius of the propeller 100 is located and which is 91.7% D9% of the radius of the propeller 100 from the center of the hub 10 is 1.29mm ± 1mm, the attack angle α of the blade 20 is α, 8613 is 9.47 ° ± 2.5 °, the L13 ° is 9, and L13 is 15.40mm ± 5mm, so as to further reduce the air resistance of the propeller 100, improve the drag and efficiency and reduce the noise, and the noise may be any one of the above-mentioned values, such as 0.9, 3.

Referring to fig. 11, in the present embodiment, optionally, the diameter of the propeller 100 is 240mm ± 24mm, when the distance between the blade 20 and the free end 222 is 7.5mm, that is, the distance between the blade 20 and the center of the hub 10 is 112.5mm, that is, when the distance between the blade 20 and the radius of the propeller 100 is 93.8% D14% from the center of the hub 10, the distance between a horizontal plane on which the airfoil rotation center of the blade 20 is located and a horizontal plane on which the airfoil rotation center of the blade 20 is located 50% of the radius of the propeller 100 is located, is 2.46mm ± 1mm, the angle of attack α of the blade 20 is 8.48 ° ± 2.5 °, the L chord length 14 of the blade 20 is 13.65mm ± 5mm, so as to further reduce the air resistance of the propeller 100, improve the pulling force and efficiency, and reduce the noise, wherein the distance between the two horizontal planes may be 1.46mm, 2.46mm, 3.46mm, 16.65mm, 16.6 mm, 16.65mm, 10.65mm, 16.65mm, 10.65 mm.

Referring to fig. 12, in the present embodiment, optionally, when the diameter of the propeller 100 is 240mm ± 24mm, and the distance between the blade 20 and the free end 222 is 5mm, that is, the distance between the blade 20 and the center of the hub 10 is 115mm, that is, the distance between the blade 20 and the horizontal plane at which the airfoil rotation center of the blade 20 is located at 50% of the radius of the propeller 100 is located at 95.8% D15 from the center of the hub 10 is 3.86mm ± 2mm, the angle of attack α of the blade 20 is 7.72 ° ± 2.5 °, and the chord length L15 of the blade 20 is 11.80mm ± 5mm, so as to further reduce the air resistance of the propeller 100, improve the pulling force and the efficiency, and reduce the noise, the distance between the two horizontal planes may be 1.86mm, 3.86mm, or 5.86mm, or 2.80mm, or 4.9.9 mm, 9.9 mm, or 4.9.9.9 mm, or 10.6 mm, 7.7.7.5 mm, or 10.7.5 mm, 14 mm, or 7.5.5 mm, 14.7.5%, or 7.7.7.5%, or 7.5%, or 7, 14.6, 7.5% of the angle of the above-7.7.5, 10.7.5, 14, 7.5, 7.7.5, 7.5, 7, 7.5, 7.7, 7.5, 7, 7.5, 7.7.5, 7.5, 7, or two of the above-7.9, 7, 7.7..

Referring to fig. 13, in the present embodiment, optionally, the diameter of the propeller 100 is 240mm ± 24mm, when the distance between the blade 20 and the free end 222 is 2.5mm, that is, the distance between the blade 20 and the center of the hub 10 is 117.5mm, that is, when the distance between the blade 20 and the radius of the propeller 100 is 97.9% D16% from the center of the hub 10, the distance between a horizontal plane on which the airfoil rotation center of the blade 20 is located and a horizontal plane on which the airfoil rotation center of the blade 20 is located 50% of the radius of the propeller 100 from the center of the hub 10 is 5.40mm ± 3mm, the angle of attack α of the blade 20 is 6.25 ° ± 2.5 °, and the chord length L16 of the blade 20 is 9.92mm ± 5mm, so as to further reduce the air resistance of the propeller 100, improve the drag and efficiency, and reduce the noise, wherein the distance between the two horizontal planes may be 2.40mm, 5.40mm, 8mm, 8.40mm, 7.40mm, 7.75 mm, 7.92mm, 14.75 mm, 14.92mm, 7.92mm, 7.75 mm, 14.92mm, 8.5 mm, 7.5mm, or 7.75 mm, 14.92mm, 14.5 mm, or 7.5mm, and the like, and the angle of the above-8.12 mm may be any of the above-8.92 mm, 7.92mm, 10.92mm, 7.75 mm, 7.92, 12 mm, 7.92mm, or 7.92mm, 7.75 mm, or 7.12 mm, or 7.92mm, 12 mm, 7.92mm, or 7.75 mm, 7.92 mm.

Referring to fig. 7, in the present embodiment, the diameter of the propeller 100 is optionally 240mm ± 24 mm. The distance between the horizontal plane on which the airfoil rotation center of the blade 20 is located and the plane XOY is 7.00mm ± 3mm from the center of the hub 10 being 100% of the radius of the propeller 100, that is, the distance between the two horizontal planes may be 4.00mm or 7.00mm or 10.00mm, or any one of 4.60mm, 5.20mm, 6.00mm, 6.80mm, 7.60mm, 8.40mm, 9.00mm, 9.60mm, or the like or a value between any two of the above, and thus, the distance between the two planes is 3.0% to 9.3% of the radius of the propeller 100, to further reduce the air resistance of the propeller 100, improve the pulling force and the efficiency, and reduce the noise.

Referring again to fig. 7 to 13, in the present embodiment, optionally, the diameter of the propeller 100 is 240mm ± 24mm, the distance between the horizontal plane where the airfoil rotation center of the blade 20 is located and the horizontal plane where the airfoil rotation center of the blade 20 is located at 50% of the radius of the propeller 100 is 0.03mm, the angle of attack α of the blade 20 is 10.52 mm, the chord length L11 of the blade 20 is 18.71mm, the distance between the blade 20 and the free end 222 is 12.5mm, the distance between the horizontal plane where the airfoil rotation center of the blade 20 is located and the horizontal plane where the airfoil rotation center of the blade 20 is located at 50% of the radius of the propeller 10 is 0.45mm, the angle of attack α of the blade 20 is 9.95 mm, the chord length L12 of the blade 20 is 17.10mm, the distance between the blade 20 and the horizontal plane where the airfoil rotation center of the blade 20 is located at 50% of the radius of the propeller 100, the propeller 100mm, the blade 20 is 260.8 mm, the horizontal plane where the airfoil rotation center of the blade 20 is located at 20mm, the distance between the horizontal plane 20mm, the horizontal plane rotation center of the airfoil rotation center of the propeller 20 is 2mm, the propeller rotation center of the propeller 20 is 2mm, the blade 20, the distance between the horizontal plane 20, the horizontal plane 20 is 2mm, the propeller rotation center of the propeller 20 is 2mm, the propeller rotation center of the propeller 20 is 2mm, the propeller rotation distance between the propeller 20 is 2mm, the propeller rotation center of the propeller 20 is 2mm, the propeller rotation center of the propeller 20 is 120mm, the propeller rotation center of the propeller rotation distance between the propeller rotation center of the propeller 20 is 120mm, the propeller rotation center of the propeller rotation distance between the propeller rotation center of the propeller 20 is 2mm, the propeller rotation center of the propeller 20 is 2mm, the propeller rotation distance between the propeller 20 is 120mm, the propeller rotation center of the propeller rotation distance between the propeller 20, the propeller rotation center of the propeller rotation distance between the propeller rotation center of the propeller 20 is 2mm, the propeller rotation center of the propeller rotation distance of the propeller rotation center of the propeller 20 is 120mm, the propeller rotation center of the propeller 20 is 2mm, the propeller rotation center of the propeller rotation distance between the propeller rotation center of the propeller 20 is 2mm, the propeller rotation distance of the propeller 20 is 2mm, the propeller rotation center of the propeller 20 is 120mm, the propeller rotation distance of the propeller 20 is 2mm, the propeller rotation center of the propeller 20.

Referring to fig. 14, in the present embodiment, optionally, at a position 25% of the radius of the propeller 100 from the center of the hub 10, D1 is provided, the angle of attack α 1 of the blade 20 is 18.95 ° ± 2.5 °, and the chord length L1 of the blade 20 is 32.01mm ± 5mm, so as to further reduce the air resistance of the propeller 100, improve the drag force and efficiency, and reduce the noise, wherein the angle of attack α 1 of the blade 20 may be 16.45 ° or 18.95 ° or 21.45 °, or may be any one or a value between 16.95 °, 17.45 °, 17.95 °, 18.45 °, 19.95 °, 20.45 °, 20.95 °, 21.45 °, and the like, and the chord length L1 of the blade 20 may be any one or a value between 27.01mm or 32.01mm or 37.01mm, or may be any one or a value between 28.01mm, 29.01mm, 30.01mm, 31.01mm, 33.01mm, 34.01mm, 35.01mm, 36.01mm, and the like.

Referring to fig. 15, in the present embodiment, optionally, at a distance of 33.3% of the radius of the propeller 100 from the center of the hub 10, D2, the angle of attack α 2 of the blade 20 is 18.38 ° ± 2.5 °, and the chord length L2 of the blade 20 is 31.05mm ± 5mm, so as to further reduce the air resistance of the propeller 100, improve the drag and efficiency, and reduce the noise, wherein the angle of attack α 2 of the blade 20 may be any one of 15.88 ° or 18.38 ° or 20.88 °, or 16.38 °, 16.88 °, 17.38 °, 17.88 °, 18.88 °, 19.38 °, 19.88 °, 20.38 °, and the like, or a value between any two of the foregoing, and the chord length L2 of the blade 20 may be any one of 26.05mm or 31.05mm or 36.05mm, or any one of 27.05mm, 28.05mm, 29.05mm, 30.05mm, 32.05mm, 33.05mm, 34.05mm, 35.05mm, and the like.

Referring to fig. 16, in the present embodiment, optionally, at a position D3 that is 41.7% of the radius of the propeller 100 from the center of the hub 10, the angle of attack α 3 of the blade 20 is 17.50 ° ± 2.5 °, and the chord length L3 of the blade 20 is 29.80mm ± 5mm, so as to further reduce the air resistance of the propeller 100, improve the drag and efficiency, and reduce the noise, wherein the angle of attack α 3 of the blade 20 may be any one of 15.00 ° or 17.50 ° or 20.00 °, or 15.50 °, 16.00 °, 16.50 °, 17.00 °, 18.00 °, 18.50 °, 19.00 °, 19.50 °, or the like, or any value therebetween, and the chord length L3 of the blade 20 may be any one of 24.80mm or 29.80mm or 34.80mm, or any value of 25.80mm, 26.80mm, 27.80mm, 28.80mm, 30.80mm, 31.80mm, 32.80mm, 33.80mm, or the like.

Referring to fig. 17, in the present embodiment, optionally, at a position 50% of the radius of the propeller 100 from the center of the hub 10, D4 is provided, the angle of attack α 4 of the blade 20 is 16.54 ° ± 2.5 °, and the chord length L4 of the blade 20 is 28.54mm ± 5mm, so as to further reduce the air resistance of the propeller 100, improve the drag force and efficiency, and reduce the noise, wherein the angle of attack α 4 of the blade 20 may be 14.04 ° or 16.54 ° or 19.04 °, or may be 14.54 °, 15.04 °, 15.54 °, 16.04 °, 17.04 °, 17.54 °, 18.04 °, 18.54 ° or the like, or any value therebetween, and the chord length L4 of the blade 20 may be 23.54mm or 28.54mm or 33.54mm, or any value therebetween, or may be 24.54mm, 25.54mm, 26.54mm, 27.54mm, 29.54mm, 30.54mm, 31.54mm, 83 mm, 32.54mm, or the like.

Referring to fig. 18, in the present embodiment, optionally, at a position 58.3% of the radius of the propeller 100 from the center of the hub 10, D5 is provided, the angle of attack α 5 of the blade 20 is 15.45 ° ± 2.5 °, and the chord length L5 of the blade 20 is 27.27mm ± 5mm, so as to further reduce the air resistance of the propeller 100, improve the drag force and efficiency, and reduce the noise, wherein the angle of attack α 5 of the blade 20 may be 12.95 ° or 15.45 ° or 17.95 °, or 13.45 °, 14.95 °, 14.45 °, 15.95 °, 16.95 °, 16.45 °, 17.95 °, 17.45 °, or the like, and the chord length L5 of the blade 20 may be any one of 22.27mm or 27.27mm or 32.27mm, or any one of 23.27mm, 24.27mm, 25.27mm, 26.27mm, 28.27mm, 29.27mm, 30.27mm, 31.27mm, or the like.

Referring to fig. 19, in the present embodiment, optionally, at a position 66.7% of the radius of the propeller 100 from the center of the hub 10, D6 is provided, the angle of attack α 6 of the blade 20 is 14.25 ° ± 2.5 °, and the chord length L6 of the blade 20 is 25.98mm ± 5mm, so as to further reduce the air resistance of the propeller 100, improve the drag and efficiency, and reduce the noise, wherein the angle of attack α 6 of the blade 20 may be 11.75 ° or 14.25 ° or 16.75 °, or may be 12.25 °, 12.75 °, 13.25 °, 13.75 °, 14.75 °, 15.25 °, 15.75 °, 16.25 °, or the like, and the chord length L6 of the blade 20 may be one of 20.98mm or 25.98mm or 30.98mm, or may be 21.98mm, 22.98mm, 23.98mm, 24.98mm, 26.98mm, 27.98mm, 28.98mm, or the like.

Referring to fig. 20, in the present embodiment, optionally, at a position 75% of the radius of the propeller 100 from the center of the hub 10, D7 is provided, an attack angle α 7 of the blade 20 is 12.97 ° ± 2.5 °, and a chord length L7 of the blade 20 is 24.71mm ± 5mm, so as to further reduce the air resistance of the propeller 100, improve the drag force and efficiency, and reduce the noise, wherein the attack angle α 7 of the blade 20 may be 10.47 ° or 12.97 ° or 15.47 °, or 10.97 °, 11.47 °, 11.97 °, 12.47 °, 13.47 °, 13.97 °, 14.47 °, 14.97 °, or the like, and the chord length L7 of the blade 20 may be any one or two of the above values, and the chord length L7 of the above-mentioned may be 19.71mm or 24.71mm or 29.71mm, or 20.71mm, 21.71mm, 22.71mm, 23.71mm, 25.71mm, 26.71mm, 27.71mm, 28.71mm, or the above-mentioned value.

Referring to fig. 21, in the present embodiment, optionally, D8 is located 83.3% of the radius of the propeller 100 from the center of the hub 10, the attack angle α 8 of the blade 20 is 11.49 ° ± 2.5 °, and the chord length L8 of the blade 20 is 21.48mm ± 5mm, so as to further reduce the air resistance of the propeller 100, improve the pulling force and the efficiency, and reduce the noise, wherein the attack angle α 8 of the blade 20 may be 8.99 ° or 11.49 ° or 13.99 °, or may be any one or a value between 9.49 °, 9.99 °, 10.49 °, 10.99 °, 11.99 °, 12.49 °, 12.99 °, 13.49 ° or the like, and the chord length L8 of the blade 20 may be 16.48mm or 21.48mm or 26.48mm, or a value between 17.48mm, 18.48mm, 19.48mm, 20.48mm, 22.48mm, 23.48mm, 24.48mm, 25.48mm, or the like.

Referring to fig. 22, in the present embodiment, optionally, at a position 91.7% of the radius of the propeller 100 from the center of the hub 10, D9, an attack angle α 9 of the blade 20 is 9.47 ° ± 2.5 °, and a chord length L9 of the blade 20 is 15.40mm ± 5mm, so as to further reduce the air resistance of the propeller 100, improve the pulling force and the efficiency, and reduce the noise, wherein the attack angle α 9 of the blade 20 may be 6.97 ° or 9.47 ° or 11.97 °, or may be any one of 7.47 °, 7.97 °, 8.47 °, 8.97 °, 9.97 °, 10.47 °, 10.97 °, 11.47 ° or the like, or a value therebetween, and the chord length L9 of the blade 20 may be any one of 10.40mm or 15.40mm or 20.40mm, or may be any one of 11.40mm, 12.40mm, 13.40mm, 14.40mm, 16.40mm, 17.40mm, 18.40mm, 19.40mm, or the like.

Referring to fig. 23, in the present embodiment, optionally, at a position D10 which is 100% of the radius of the propeller 100 from the center of the hub 10, the angle of attack α 10 of the blade 20 is 5.94 ° ± 2.5 °, and the chord length L10 of the blade 20 is 3.61mm ± 2mm, so as to further reduce the air resistance of the propeller 100, improve the drag force and efficiency, and reduce the noise, wherein the angle of attack α 10 of the blade 20 may be 3.44 ° or 5.94 ° or 8.44 °, or any one or a value between 3.94 °, 4.44 °, 4.94 °, 5.44 °, 6.44 °, 6.94 °, 7.44 °, 7.94 ° or the like, and the chord length L10 of the blade 20 may be 1.61mm or 3.61mm or 5.61mm, or any one or a value between 2.11mm, 2.61mm, 3.11mm, 4.11mm, 4.61mm, 5.11mm, or the like.

Referring again to fig. 14 to 23, in the present embodiment, optionally, the diameter of the propeller 100 is 240mm ± 24mm, D1 at 30mm from the center of the hub 10, the angle of attack α of the blade 20 is 18.95 °, the chord length L1 of the blade 20 is 32.01mm, D2 at 40mm from the center of the hub 10, the angle of attack α 2 of the blade 20 is 18.38 °, the chord length L2 of the blade 20 is 31.05mm, D3 at 50mm from the center of the hub 10, the angle of attack α of the blade 20 is 17.50 °, the chord length L3 of the blade 20 is 29.80mm, D4 at 60mm from the center of the hub 10, the angle of attack 4 of the blade 20 is 16.54 °, the chord length L72 of the blade 20 is 28.54mm, D4 at 70mm from the center of the hub 10, D4 mm, the chord length L4 mm of the blade 20 is 28.54mm, the chord length L4 mm at 70mm from the center of the hub 10, the center of the blade 72 mm, the angle of the blade 72 mm is 36mm, the chord length L36 mm, the angle of the blade 72 mm is 240mm, the angle of the blade 72 mm, the angle of the blade 72 mm is 3.28.28.28.28 mm, the angle of the blade 72 mm, the angle of the center of the angle of the blade 72 mm, the angle of the center of the angle of the blade 72 mm, the angle of the blade 72 mm is 36mm, the angle of the blade 72 mm, the angle of the angle.

In this embodiment, the pitch of the blades 20 is optionally 5.36 ± 0.5 inches. The pitch in this embodiment refers to the pitch at 3/4 of the radius of the propeller 100. Thereby, the drag of the air can be reduced, and the pulling force of the blade 20 can be increased. Wherein the pitch of the blades 20 may be 4.86 inches, or 5.36 inches, or 5.86 inches, or any one or a number between 4.96 inches, 5.06 inches, 5.16 inches, 5.26 inches, 5.46 inches, 5.56 inches, 5.66 inches, 5.76 inches, etc.

In conclusion, the propeller 100 with the gradually changed airfoil shape of the blades 20 according to the embodiment of the present invention can significantly improve the tension in the plateau area, and ensure sufficient power redundancy. Meanwhile, the performance is considered to a certain extent, the following flight distance is increased, and the flight performance of the aircraft 1000 is improved. Compared with the existing propeller 100 on the market, the propeller 100 adopting the paddle has larger pulling force under the condition of lower power, thereby reducing the electric quantity loss and increasing the cruising distance. Under the extreme condition that the takeoff weight is larger in a high-altitude area or a low-altitude area with reduced density, the aircraft can obviously improve the pulling force, ensure enough power and prolong the endurance time at the same time, and improve the flight performance. In addition, the present embodiment provides a propeller 100 having a loudness that is significantly lower than that of existing propellers at the same high frequencies. Therefore, the propeller 100 provided by the embodiment can effectively reduce high-frequency noise, reduce discomfort of human ears caused by the high-frequency noise, and improve user experience.

In some embodiments, the distance between a horizontal plane in which the airfoil center of rotation of the blades 20 lies and a horizontal plane in which the airfoil center of rotation of the blades 20 lies at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 2.6% to 7.0% of the radius of the propeller 100 at a distance of 97.9% of the radius of the propeller 100 from the center of the hub 10; and/or

The distance between the horizontal plane where the airfoil rotation center of the blade 20 is located and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 95.8% of the radius of the propeller 100 from the center of the hub 10 and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 1.4% to 5.4% of the radius of the propeller 100; and/or

The distance between the horizontal plane where the airfoil rotation center of the blade 20 is located and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 93.8% of the radius of the propeller 100 from the center of the hub 10 and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 1.1% to 3.2% of the radius of the propeller 100; and/or

The distance between the horizontal plane where the airfoil rotation center of the blade 20 is located and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 91.7% of the radius of the propeller 100 from the center of the hub 10 and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 0.2% to 2.1% of the radius of the propeller 100; and/or

The distance between the horizontal plane where the airfoil rotation center of the blade 20 is located and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 89.2% of the radius of the propeller 100 from the center of the hub 10 and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 0.2% to 0.6% of the radius of the propeller 100; and/or

The distance between the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 87.5% of the radius of the propeller 100 from the center of the hub 10 and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 0.02% to 0.04% of the radius of the propeller 100; and/or

At a distance of 120mm from the center of the hub 10, the distance between a horizontal plane on which the airfoil rotation center of the blade 20 is located and a horizontal plane on which the airfoil rotation center of the blade 20 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is located is 7.00mm ± 3 mm; and/or

The distance between the horizontal plane where the airfoil rotation center of the blade 20 is located and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 117.5mm from the center of the hub 10 and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 5.40mm ± 3 mm; and/or

The distance between the horizontal plane of the airfoil rotation center of the blade 20 at a distance of 115mm from the center of the hub 10 and the horizontal plane of the airfoil rotation center of the blade 20 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 3.86mm ± 2 mm; and/or

The distance between the horizontal plane of the airfoil rotation center of the blade 20 at a distance of 112.5mm from the center of the hub 10 and the horizontal plane of the airfoil rotation center of the blade 20 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 2.46mm ± 1 mm; and/or

At a distance of 110mm from the center of the hub 10, the distance between a horizontal plane on which the airfoil rotation center of the blade 20 is located and a horizontal plane on which the airfoil rotation center of the blade 20 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is located is 1.29mm ± 1 mm; and/or

At a distance of 107.5mm from the center of the hub 10, the distance between a horizontal plane on which the airfoil rotation center of the blade 20 is located and a horizontal plane on which the airfoil rotation center of the blade 20 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is located is 0.45mm ± 0.2 mm; and/or

The distance between the horizontal plane in which the centre of rotation of the airfoil of the blade 20 lies and the horizontal plane in which the centre of rotation of the airfoil of the blade 20 lies at a distance of 50% of the radius of the propeller 100 from the centre of the hub 10 is 0.03mm ± 0.01mm at 105mm from the centre of the hub 10.

The discussion herein includes, but is not limited to, the following:

(1) the distance between the horizontal plane where the airfoil rotation center of the blade 20 is located and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 97.9% of the radius of the propeller 100 from the center of the hub 10 and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 2.6% to 7.0% of the radius of the propeller 100;

(2) the distance between the horizontal plane where the airfoil rotation center of the blade 20 is located and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 95.8% of the radius of the propeller 100 from the center of the hub 10 and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 1.4% to 5.4% of the radius of the propeller 100;

(3) the distance between the horizontal plane where the airfoil rotation center of the blade 20 is located and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 93.8% of the radius of the propeller 100 from the center of the hub 10 and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 1.1% to 3.2% of the radius of the propeller 100;

(4) the distance between the horizontal plane where the airfoil rotation center of the blade 20 is located and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 91.7% of the radius of the propeller 100 from the center of the hub 10 and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 0.2% to 2.1% of the radius of the propeller 100;

(5) the distance between the horizontal plane where the airfoil rotation center of the blade 20 is located and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 89.2% of the radius of the propeller 100 from the center of the hub 10 and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 0.2% to 0.6% of the radius of the propeller 100;

(6) the distance between the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 87.5% of the radius of the propeller 100 from the center of the hub 10 and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 0.02% to 0.04% of the radius of the propeller 100;

(1) at a distance of 120mm from the center of the hub 10, the distance between a horizontal plane on which the airfoil rotation center of the blade 20 is located and a horizontal plane on which the airfoil rotation center of the blade 20 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is located is 7.00mm ± 3 mm;

(7) the distance between the horizontal plane where the airfoil rotation center of the blade 20 is located and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 117.5mm from the center of the hub 10 and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 5.40mm ± 3 mm;

(8) the distance between the horizontal plane of the airfoil rotation center of the blade 20 at a distance of 115mm from the center of the hub 10 and the horizontal plane of the airfoil rotation center of the blade 20 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 3.86mm ± 2 mm;

(9) the distance between the horizontal plane of the airfoil rotation center of the blade 20 at a distance of 112.5mm from the center of the hub 10 and the horizontal plane of the airfoil rotation center of the blade 20 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 2.46mm ± 1 mm;

(10) at a distance of 110mm from the center of the hub 10, the distance between a horizontal plane on which the airfoil rotation center of the blade 20 is located and a horizontal plane on which the airfoil rotation center of the blade 20 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is located is 1.29mm ± 1 mm;

(11) at a distance of 107.5mm from the center of the hub 10, the distance between a horizontal plane on which the airfoil rotation center of the blade 20 is located and a horizontal plane on which the airfoil rotation center of the blade 20 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is located is 0.45mm ± 0.2 mm;

(12) at a distance of 105mm from the center of the hub 10, the distance between a horizontal plane on which the airfoil rotation center of the blade 20 is located and a horizontal plane on which the airfoil rotation center of the blade 20 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is located is 0.03mm ± 0.01 mm;

(13) the distance between the horizontal plane where the airfoil rotation center of the blade 20 is located and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 97.9% of the radius of the propeller 100 from the center of the hub 10 and the horizontal plane where the airfoil rotation center of the blade 20 is located at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 2.6% to 7.0% of the radius of the propeller 100; and, at a distance of 95.8% of the radius of the propeller 100 from the center of the hub 10, the distance between a horizontal plane on which the airfoil-shaped rotation center of the blade 20 is located and a horizontal plane on which the airfoil-shaped rotation center of the blade 20 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is located is 1.4% to 5.4% of the radius of the propeller 100; and, at a distance of 93.8% of the radius of the propeller 100 from the center of the hub 10, the distance between a horizontal plane on which the airfoil-shaped rotation center of the blade 20 is located and a horizontal plane on which the airfoil-shaped rotation center of the blade 20 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is located is 1.1% to 3.2% of the radius of the propeller 100; and, at a distance of 91.7% of the radius of the propeller 100 from the center of the hub 10, the distance between a horizontal plane on which the airfoil-shaped rotation center of the blade 20 is located and a horizontal plane on which the airfoil-shaped rotation center of the blade 20 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is located is 0.2% to 2.1% of the radius of the propeller 100; and, at a distance of 89.2% of the radius of the propeller 100 from the center of the hub 10, the distance between the horizontal plane on which the airfoil-shaped rotation center of the blade 20 is located and the horizontal plane on which the airfoil-shaped rotation center of the blade 20 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is located is 0.2% to 0.6% of the radius of the propeller 100; and, at 87.5% of the radius of the propeller 100 from the center of the hub 10, the distance between the horizontal plane on which the airfoil rotation center of the blade 20 is located and the horizontal plane on which the airfoil rotation center of the blade 20 at 50% of the radius of the propeller 100 from the center of the hub 10 is located is 0.02% to 0.04% of the radius of the propeller 100; and, at a distance of 120mm from the center of the hub 10, the distance between the horizontal plane on which the airfoil rotation center of the blade 20 is located and the horizontal plane on which the airfoil rotation center of the blade 20 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is located is 7.00mm ± 3 mm; and, at 117.5mm from the center of the hub 10, the distance between the horizontal plane on which the airfoil rotation center of the blade 20 is located and the horizontal plane on which the airfoil rotation center of the blade 20 at 50% of the radius of the propeller 100 is located from the center of the hub 10 is 5.40mm ± 3 mm; and, at a distance of 115mm from the center of the hub 10, the distance between the horizontal plane on which the airfoil rotation center of the blade 20 is located and the horizontal plane on which the airfoil rotation center of the blade 20 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is located is 3.86mm ± 2 mm; and, at 112.5mm from the center of the hub 10, the distance between the horizontal plane on which the airfoil rotation center of the blade 20 is located and the horizontal plane on which the airfoil rotation center of the blade 20 at 50% of the radius of the propeller 100 is located from the center of the hub 10 is 2.46mm ± 1 mm; and, at a distance of 110mm from the center of the hub 10, the distance between the horizontal plane on which the airfoil rotation center of the blade 20 is located and the horizontal plane on which the airfoil rotation center of the blade 20 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is located is 1.29mm ± 1 mm; and, at a distance of 107.5mm from the center of the hub 10, the distance between the horizontal plane on which the airfoil rotation center of the blade 20 is located and the horizontal plane on which the airfoil rotation center of the blade 20 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is located is 0.45mm ± 0.2 mm; and, at a distance of 105mm from the center of the hub 10, the distance between the horizontal plane on which the airfoil rotation center of the blade 20 is located and the horizontal plane on which the airfoil rotation center of the blade 20 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is located is 0.03mm ± 0.01 mm.

In some embodiments, the propeller 100 has an angle of attack α 3 of 17.50 ° ± 2.5 ° and/or the blades 20 are at a distance D3 from the center of the hub 10 of 41.7% of the radius of the propeller 100

The angle of attack α 4 of the blades 20 is 16.54 ° ± 2.5 ° at a distance D4 from the center of the hub 10 of 50% of the radius of the propeller 100, and/or

The angle of attack α 5 of the blades 20 is 15.45 ° ± 2.5 ° at a distance D5 from the center of the hub 10 of 58.3% of the radius of the propeller 100, and/or

The angle of attack α 6 of the blades 20 is 14.25 ° ± 2.5 ° at a distance D6 of 66.7% of the radius of the propeller 100 from the center of the hub 10, and/or

At a distance D7 of 75% of the radius of the propeller 100 from the center of the hub 10, the angle of attack α 7 of the blades 20 is 12.97 ° ± 2.5 °.

The discussion herein includes, but is not limited to, the following:

(1) the propeller 100 is at 41.7% of the radius of the propeller 100 from the center of the hub 10D 3, the angle of attack α 3 of the blades 20 is 17.50 ° ± 2.5 °;

(2) the propeller 100 is at 50% of the radius of the propeller 100 from the center of the hub 10D 4, the angle of attack α 4 of the blades 20 is 16.54 ° ± 2.5 °;

(3) the propeller 100 is at 58.3% of the radius of the propeller 100 from the center of the hub 10D 5, the angle of attack α 5 of the blades 20 is 15.45 ° ± 2.5 °;

(4) propeller 100 is at 66.7% of the radius of propeller 100 from the center of hub 10D 6, and angle of attack α 6 of blades 20 is 14.25 ° ± 2.5 °;

(5) propeller 100 is at 75% of the radius of propeller 100 from the center of hub 10, D7, and angle of attack α 7 of blades 20 is 12.97 ° ± 2.5 °;

(6) propeller 100 has an angle of attack α of blade 20 of 17.50 ° ± 2.5 ° at a distance D3 from the center of hub 10 of 41.7% of the radius of propeller 100, and angle of attack α of blade 20 of 16.54 ° ± 2.5 ° at a distance D4 from the center of hub 10 of 50% of the radius of propeller 100, and angle of attack α of blade 20 of 15.45 ° ± 2.5 ° at a distance D5 from the center of hub 10 of 58.3% of the radius of propeller 100, and angle of attack 355636 of blade 20 of 15.45 ° ± 2.5 ° at a distance D5636 from the center of hub 10 of the radius of propeller 100, and angle of attack α of blade 20 of 12.97 ° ± 2.5 ° at a distance D7 from the center of hub 10 of 75% of the radius of propeller 100.

In some embodiments, the propeller 100 has an angle of attack α 1 of 18.95 ° ± 2.5 ° at a distance D1 from the center of the hub 10 that is 25% of the radius of the propeller 100, and/or the blades 20 have

The angle of attack α 2 of the blades 20 is 18.38 ° ± 2.5 ° at a distance D2 of 33.3% of the radius of the propeller 100 from the center of the hub 10, and/or

The angle of attack α 8 of the blades 20 is 11.49 ° ± 2.5 ° at a distance D8 from the center of the hub 10 of 83.3% of the radius of the propeller 100, and/or

The angle of attack α 9 of the blades 20 is 9.47 ° ± 2.5 ° at a distance D9 from the center of the hub 10 of 91.7% of the radius of the propeller 100, and/or

The angle of attack α 10 of the blades 20 is 5.94 ° ± 2.5 ° at a distance D10 from the center of the hub 10 of 100% of the radius of the propeller 100, and/or

An angle of attack α 1 of the blade 20 of 18.95 DEG at a distance D1 of 30mm from the center of the hub 10, and/or

An angle of attack α 2 of the blade 20 of 18.38 DEG at a distance D2 of 40mm from the center of the hub 10, and/or

An angle of attack α 3 of 17.50 DEG at a distance D3 of 50mm from the center of hub 10, and/or

An angle of attack α 4 of the blade 20 of 16.54 degrees at a distance D4 of 60mm from the center of the hub 10, and/or

An angle of attack α 5 of the blade 20 of 15.45 DEG at a distance D5 of 70mm from the center of the hub 10, and/or

An angle of attack α 6 of the blade 20 of 14.25 DEG at a distance D6 of 80mm from the center of the hub 10, and/or

An angle of attack α 7 of the blade 20 of 12.97 DEG at a distance D7 of 90mm from the center of the hub 10, and/or

An angle of attack α 8 of the blade 20 of 11.49 DEG at a distance D8 of 100mm from the center of the hub 10, and/or

An angle of attack α 9 of the blade 20 of 9.47 DEG at a distance D9 of 110mm from the center of the hub 10, and/or

At 120mm from the center of the hub 10, D10, the angle of attack α 10 of the blade 20 is 5.94 °.

The discussion herein includes, but is not limited to, the following:

(1) propeller 100 is at 25% of the radius of propeller 100 from the center of hub 10, D1, and angle of attack α 1 of blades 20 is 18.95 ° ± 2.5 °;

(2) propeller 100 is at 33.3% of the radius of propeller 100 from the center of hub 10D 2, and angle of attack α 2 of blades 20 is 18.38 ° ± 2.5 °;

(3) the propeller 100 is at 83.3% of the radius of the propeller 100 from the center of the hub 10D 8, the angle of attack α 8 of the blades 20 is 11.49 ° ± 2.5 °;

(4) propeller 100 is at 91.7% of the radius of propeller 100 from the center of hub 10D 9, and angle of attack α 9 of blades 20 is 9.47 ° ± 2.5 °;

(5) the propeller 100 is at 100% of the radius of the propeller 100 from the center of the hub 10D 10, the angle of attack α 10 of the blades 20 is 5.94 ° ± 2.5 °;

(6) propeller 100 at 30mm from the center of hub 10D 1, angle of attack α 1 of blades 20 is 18.95 °;

(7) propeller 100 at 40mm from the center of hub 10D 2, blade 20 has an angle of attack α 2 of 18.38 °;

(8) propeller 100 at 50mm from the center of hub 10D 3, angle of attack α 3 of blade 20 is 17.50 °;

(9) propeller 100 at 60mm from the center of hub 10D 4, blade 20 has an angle of attack α 4 of 16.54 °;

(10) the propeller 100 is at 70mm from the center of the hub 10D 5, the angle of attack α 5 of the blades 20 is 15.45 °;

(11) propeller 100 at 80mm from the center of hub 10D 6, blade 20 has an angle of attack α 6 of 14.25 °;

(12) propeller 100 at 90mm from the center of hub 10D 7, blade 20 has an angle of attack α 7 of 12.97 °;

(13) propeller 100 at 100mm from the center of hub 10D 8, blade 20 has an angle of attack α 8 of 11.49 °;

(14) propeller 100 at 110mm from the center of hub 10D 9, angle of attack α 9 of blades 20 is 9.47 °;

(15) the propeller 100 has an angle of attack α 10 of 5.94 ° at 120mm from the center of the hub 10D 10 for the blades 20.

(16) The rotor 100 has an angle of attack α of 18.95 ° ± 2.5 ° at a distance of 25% of the radius of the rotor 100 from the center of the hub 10, D2 at a distance of 33.3% of the radius of the rotor 100 from the center of the hub 10, the angle of attack α of the blades 20 is 18.38 ° ± 2.5 ° at the angle of attack α of 18.38 ° ± 2.5 ° at a distance of 83.3% of the radius of the rotor 100 from the center of the hub 10, the angle of attack α 08 of the blades 20 is 11.49 ° ± 2.5 ° at the angle of attack 3.3% of the radius of the rotor 100, D9 at a distance of 91.7% of the radius of the rotor 100 from the center of the hub 10, the angle of attack α of the blades 20 is 9.47 ° ± 2.5 ° at the angle of attack 10, D10 at a distance of 100% of the radius of the rotor 100 from the center of the hub 10, the angle α mm of the blade 72 mm at the angle of the center of the rotor 10, the angle of the rotor 72 mm, the center of the angle of the rotor 72 mm, the rotor 72 mm at the angle of the center of the rotor 72 mm, the angle of the rotor 72 mm at the rotor 10mm, the center of the rotor 10mm, the angle of the rotor 72 mm, the rotor 72 mm at the rotor 10mm, the angle of the rotor 72 mm at the angle of the rotor 10mm, the angle of the rotor 72 mm, the rotor 10mm, the rotor 72 mm at the rotor 10mm, the angle of the rotor 72 mm, the angle of the rotor 10mm, the rotor 72 mm, the rotor 10mm, the angle of the rotor 10mm, the rotor 72 mm, the rotor 10mm, the rotor 72 mm, the angle of the rotor 72.

In certain embodiments, the propeller 100 is D3 at 41.7% of the radius of the propeller 100 from the center of the hub 10, the chord length L3 of the blades 20 is 29.80mm ± 5 mm; and/or

At a distance D4 of 50% of the radius of the propeller 100 from the centre of the hub 10, the chord length L4 of the blade 20 is 28.54mm ± 5 mm; and/or

At a distance D5 of 58.3% of the radius of the propeller 100 from the centre of the hub 10, the chord length L5 of the blade 20 is 27.27mm ± 5 mm; and/or

At 66.7% of the radius of the propeller 100 from the centre of the hub 10D 6, the chord length L6 of the blade 20 is 25.98mm ± 5 mm; and/or

At a distance D7 of 75% of the radius of the propeller 100 from the centre of the hub 10, the chord length L7 of the blades 20 is 24.71mm ± 5 mm; and/or

At a distance D3 of 50mm from the centre of the hub 10, the chord length L3 of the blade 20 is 29.80 mm; and/or

At 60mm from the centre of the hub 10D 4, the chord length L4 of the blade 20 is 28.54 mm; and/or

At 70mm from the centre of the hub 10D 5, the chord length L5 of the blade 20 is 27.27 mm; and/or

At 80mm from the centre of the hub 10D 6, the chord length L6 of the blade 20 is 25.98 mm; and/or

At 90mm from the centre of the hub 10D 7, the chord length L7 of the blade 20 is 24.71 mm.

The discussion herein includes, but is not limited to, the following:

(1) the propeller 100 is D3 at a distance of 41.7% of the radius of the propeller 100 from the center of the hub 10, and the chord length L3 of the blades 20 is 29.80mm +/-5 mm;

(2) the propeller 100 is D4 at a distance of 50% of the radius of the propeller 100 from the center of the hub 10, and the chord length L4 of the blade 20 is 28.54mm +/-5 mm;

(3) the propeller 100 is at a distance D5 of 58.3% of the radius of the propeller 100 from the center of the hub 10, and the chord length L5 of the blades 20 is 27.27mm +/-5 mm;

(4) the propeller 100 is D6 at a distance of 66.7% of the radius of the propeller 100 from the center of the hub 10, and the chord length L6 of the blades 20 is 25.98mm +/-5 mm;

(5) the propeller 100 is D7 at a distance of 75% of the radius of the propeller 100 from the center of the hub 10, and the chord length L7 of the blades 20 is 24.71mm +/-5 mm;

(6) the propeller 100 is at 50mm from the center of the hub 10D 3, and the chord length L3 of the blade 20 is 29.80 mm;

(7) the propeller 100 is at a distance of 60mm from the center of the hub 10D 4, and the chord length L4 of the blade 20 is 28.54 mm;

(8) the propeller 100 is at 70mm from the center of the hub 10D 5, the chord length L5 of the blade 20 is 27.27 mm;

(9) the propeller 100 is at 80mm from the center of the hub 10D 6, and the chord length L6 of the blade 20 is 25.98 mm;

(10) the propeller 100 is at 90mm from the center of the hub 10D 7, and the chord length L7 of the blade 20 is 24.71 mm;

(11) the propeller 100 is D3 at a distance of 41.7% of the radius of the propeller 100 from the center of the hub 10, and the chord length L3 of the blades 20 is 29.80mm +/-5 mm; and, at a distance D4 of 50% of the radius of the propeller 100 from the center of the hub 10, the chord length L4 of the blade 20 is 28.54mm ± 5 mm; and D5 at a distance of 58.3% of the radius of the propeller 100 from the center of the hub 10, the chord length L5 of the blades 20 is 27.27mm ± 5 mm; and D6 at 66.7% of the radius of the propeller 100 from the center of the hub 10, the chord length L6 of the blades 20 is 25.98mm ± 5 mm; and, at a distance D7 of 75% of the radius of the propeller 100 from the center of the hub 10, the chord length L7 of the blades 20 is 24.71mm ± 5 mm; and, at a distance of 50mm from the centre of the hub 10, D3, the chord length L3 of the blade 20 is 29.80 mm; and, at a distance of 60mm from the centre of the hub 10, D4, the chord length L4 of the blade 20 is 28.54 mm; and, at a distance of 70mm from the centre of the hub 10, D5, the chord length L5 of the blade 20 is 27.27 mm; and, at a distance of 80mm from the centre of the hub 10, D6, the chord length L6 of the blade 20 is 25.98 mm; and a chord length L7 of the blade 20 of 24.71mm at a distance D7 of 90mm from the center of the hub 10.

In certain embodiments, the propeller 100 is D1 at a distance of 25% of the radius of the propeller 100 from the center of the hub 10, the chord length L1 of the blades 20 is 32.01mm ± 5 mm; and/or

At a distance D2 of 33.3% of the radius of the propeller 100 from the centre of the hub 10, the chord length L2 of the blades 20 is 31.05mm ± 5 mm; and/or

At a distance D8 of 83.3% of the radius of the propeller 100 from the centre of the hub 10, the chord length L8 of the blade 20 is 21.48mm ± 5 mm; and/or

At a distance D9 of 91.7% of the radius of the propeller 100 from the centre of the hub 10, the chord length L9 of the blade 20 is 15.40mm ± 5 mm; and/or

At a distance D10 from the centre of the hub 10 of 100% of the radius of the propeller 100, the chord length L10 of the blade 20 is 3.61mm ± 2 mm; and/or

At 30mm from the centre of the hub 10D 1, the chord length L1 of the blade 20 is 32.01 mm; and/or

At 40mm from the centre of the hub 10D 2, the chord length L2 of the blade 20 is 31.05 mm; and/or

At a distance of 100mm from the centre of the hub 10D 8, the chord length L8 of the blade 20 is 21.48 mm; and/or

At a distance D9 of 110mm from the centre of the hub 10, the chord length L9 of the blade 20 is 15.40 mm; and/or

At 120mm from the centre of the hub 10D 10, the chord length L10 of the blade 20 is 3.61 mm.

The discussion herein includes, but is not limited to, the following:

(1) the propeller 100 is D1 at a distance of 25% of the radius of the propeller 100 from the center of the hub 10, and the chord length L1 of the blades 20 is 32.01mm +/-5 mm;

(2) the propeller 100 is D2 at 33.3% of the radius of the propeller 100 from the center of the hub 10, and the chord length L2 of the blades 20 is 31.05mm +/-5 mm;

(3) the propeller 100 is D8 at a distance of 83.3% of the radius of the propeller 100 from the center of the hub 10, and the chord length L8 of the blades 20 is 21.48mm +/-5 mm;

(4) the propeller 100 is D9 at a distance of 91.7% of the radius of the propeller 100 from the center of the hub 10, and the chord length L9 of the blades 20 is 15.40mm +/-5 mm;

(5) the propeller 100 is D10 at a distance D of 100% of the radius of the propeller 100 from the center of the hub 10, and the chord length L10 of the blade 20 is 3.61mm +/-2 mm;

(6) the propeller 100 is at 30mm from the center of the hub 10D 1, and the chord length L1 of the blade 20 is 32.01 mm;

(7) the propeller 100 is at a distance of 40mm from the center of the hub 10, D2, and the chord length L2 of the blade 20 is 31.05 mm;

(8) the propeller 100 is at a distance of 100mm from the center of the hub 10, D8, and the chord length L8 of the blade 20 is 21.48 mm;

(9) the propeller 100 is at 110mm from the center of the hub 10D 9, and the chord length L9 of the blade 20 is 15.40 mm;

(10) the propeller 100 is 120mm from the center of the hub 10 at D10, and the chord length L10 of the blade 20 is 3.61 mm;

(11) the propeller 100 is D1 at a distance of 25% of the radius of the propeller 100 from the center of the hub 10, and the chord length L1 of the blades 20 is 32.01mm +/-5 mm; and D2 at 33.3% of the radius of the propeller 100 from the center of the hub 10, the chord length L2 of the blades 20 is 31.05mm ± 5 mm; and D8 at a distance D of 83.3% of the radius of the propeller 100 from the center of the hub 10, the chord length L8 of the blade 20 being 21.48mm ± 5 mm; and D9 at a distance of 91.7% of the radius of the propeller 100 from the center of the hub 10, the chord length L9 of the blades 20 is 15.40mm ± 5 mm; and, at a distance D10 from the center of the hub 10 of 100% of the radius of the propeller 100, the chord length L10 of the blade 20 is 3.61mm ± 2 mm; and, at a distance of 30mm from the centre of the hub 10, D1, the chord length L1 of the blade 20 is 32.01 mm; and, at a distance of 40mm from the centre of the hub 10, D2, the chord length L2 of the blade 20 is 31.05 mm; and, at a distance of 100mm from the centre of the hub 10, D8, the chord length L8 of the blade 20 is 21.48 mm; and, at a distance of 110mm from the centre of the hub 10, D9, the chord length L9 of the blade 20 is 15.40 mm; and a chord length L10 of the blade 20 of 3.61mm at a distance D10 of 120mm from the center of the hub 10.

Referring to fig. 24, an embodiment of the present invention provides a power assembly 200, which includes a driving member 30 and a propeller 100 according to any embodiment of the present invention, wherein the propeller 100 is connected to the driving member 30 through a hub 10. The power assembly 200 includes at least two horn 40. At least two horn 40 are attached to the propeller assembly 100 at a central location. The drive member 30 is disposed on the horn 40. The specific structure of the propeller 100 is the same as that of the previous embodiment, and is not described herein again. That is, the description of the propeller 100 in the above embodiments and embodiments is equally applicable to the power assembly 200 provided in the embodiments of the present invention.

In the power assembly 200 of the embodiment of the present invention, since the blade tip 22 extends obliquely along the span direction of the blade 20 toward the side where the pressure surface 23 is located, and the distance between the horizontal plane on which the airfoil rotation center of the blade 20 is located at a distance of 100% of the radius of the propeller 100 from the center of the hub 10 and the horizontal plane on which the airfoil rotation center of the blade 20 is located at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 3.0% to 9.3% of the radius of the propeller 100, therefore, the blades 20 with specific shapes are defined by the parameters, and the propeller 100 adopting the blades 20 can reduce the air resistance of the propeller 100, improve the pulling force and the efficiency, increase the secondary flight distance of the aircraft 1000 to improve the flight performance of the aircraft 1000, and reduce the noise generated by the blades 20 during operation, so that the aircraft 1000 is quieter during hovering, and the user experience is improved.

In this embodiment, the driving member 30 is optionally a motor, and the KV value of the motor is 720 ± 72 rotations/(min · v). The KV value of the motor may be any one of 648 rpm/(min · v), 720 rpm/(min · v), 792 rpm/(min · v), 663 rpm/(min · v), 678 rpm/(min · v), 693 rpm/(min · v), 708 rpm/(min · v), 723 rpm/(min · v), 738 rpm/(min · v), 760 rpm/(min · v), 788 rpm/(min · v), or any two of the foregoing. Therefore, the power performance of the power assembly can be ensured.

Referring again to fig. 24, an embodiment of the present invention provides an aircraft 1000 including a fuselage 50 and a power assembly 200 according to any embodiment of the present invention, the power assembly 200 being coupled to the fuselage 50. A plurality of horn 40 of power assembly 200 are coupled to fuselage 50 to mount power assembly 200 to fuselage 50. The specific structure of the power assembly 200 is similar to the previous embodiment, and is not described herein again. That is, the description of the propeller 100 in the above embodiments and embodiments is equally applicable to the aircraft 1000 provided by the embodiments of the present invention.

In this embodiment, the aircraft 1000 optionally includes a plurality of power assemblies 200, and the plurality of power assemblies 200 rotate in different directions.

In this embodiment, optionally, the aircraft 1000 is a multi-rotor aircraft, such as a quad-rotor unmanned aircraft.

In the aircraft 1000 of the embodiment of the invention, since the tip 22 extends obliquely along the span of the blade 20 toward the side on which the pressure surface 23 is located, and the distance between the horizontal plane on which the airfoil rotation center of the blade 20 is located at a distance of 100% of the radius of the propeller 100 from the center of the hub 10 and the horizontal plane on which the airfoil rotation center of the blade 20 is located at a distance of 50% of the radius of the propeller 100 from the center of the hub 10 is 3.0% to 9.3% of the radius of the propeller 100, therefore, the blades 20 with specific shapes are defined by the parameters, and the propeller 100 adopting the blades 20 can reduce the air resistance of the propeller 100, improve the pulling force and the efficiency, increase the secondary flight distance of the aircraft 1000 to improve the flight performance of the aircraft 1000, and reduce the noise generated by the blades 20 during operation, so that the aircraft 1000 is quieter during hovering, and the user experience is improved.

Although the present invention has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.

The disclosure of this patent document contains material which is subject to copyright protection. The copyright is owned by the copyright owner. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the patent and trademark office official records and records.

Claims

1. A propeller, comprising: a hub and blades attached to said hub, characterized in that:

the paddle comprises a paddle root, a paddle tip, a pressure surface and a suction surface, wherein the paddle tip is deviated from the paddle root;

the blade tip extends towards one side of the pressure surface along the spanwise direction of the blade in an inclined mode;

the distance between a horizontal plane in which the airfoil-shaped rotation center of the blade is located and a horizontal plane in which the airfoil-shaped rotation center of the blade is located at a position that is located at a distance of 100% of the radius of the propeller from the center of the hub and a horizontal plane in which the airfoil-shaped rotation center of the blade is located at a distance of 50% of the radius of the propeller from the center of the hub is 3.0% to 9.3% of the radius of the propeller.

2. The propeller of claim 1, wherein:

the distance between a horizontal plane in which the airfoil rotation center of the blade is located and a horizontal plane in which the airfoil rotation center of the blade is located at a distance of 97.9% of the radius of the propeller from the center of the hub and a horizontal plane in which the airfoil rotation center of the blade is located at a distance of 50% of the radius of the propeller from the center of the hub is 2.6% to 7.0% of the radius of the propeller; and/or

3. The propeller of claim 1, wherein:

the angle of attack of the blades is 17.50 ° ± 2.5 ° at a distance of 41.7% of the radius of the propeller from the center of the hub; and/or

4. The propeller of claim 3, wherein:

the angle of attack of the blades is 18.95 ° ± 2.5 ° at a distance from the centre of the hub of 25% of the radius of the propeller; and/or

At 110mm from the centre of the hub, the angle of attack of the blade is 9.47 °; and/or

At 120mm from the centre of the hub, the angle of attack of the blade is 5.94 °.

5. The propeller of claim 3, wherein:

the chord length of the blade is 29.80mm ± 5mm at a distance of 41.7% of the radius of the propeller from the centre of the hub; and/or

6. The propeller of claim 5, wherein:

the chord length of the blade is 32.01mm + -5 mm at a distance of 25% of the radius of the propeller from the center of the hub; and/or

The chord length of the blade is 3.61mm at 120mm from the centre of the hub.

7. The propeller of claim 1, wherein:

the diameter of the propeller is 240mm +/-24 mm; and/or

The pitch of the blade is 5.36 + -0.5 inches.

8. The propeller of any one of claims 1 to 7, wherein:

the blade also comprises a front edge connected to one side of the pressure surface and the suction surface, a rear edge connected to the other side of the pressure surface and the suction surface, and a swept-back part formed at the blade tip, wherein the swept-back part extends from the front edge to the rear edge in an inclined manner; and/or

9. The propeller of claim 8, wherein:

the blade forms a return bend at the position of the blade tip, the front edge extends obliquely from the return bend along the span direction of the blade towards the side where the pressure surface is located, the sweepback extends obliquely from the return bend from the front edge to the rear edge, and the distance from the return bend to the center of the hub is 87.5% of the radius of the propeller.

10. The propeller of claim 8, wherein:

the number of the blades is at least two, and the at least two blades are connected to the hub and are in central symmetry with respect to the center of the hub; and/or

The suction surface and the pressure surface are both curved surfaces.

11. A power assembly comprises a driving piece and a propeller, and is characterized in that the propeller comprises a hub and blades, the blades are connected to the hub, and the blades comprise a root, a tip, a pressure surface and a suction surface, wherein the tip is far away from the root; the blade tip extends towards one side of the pressure surface along the spanwise direction of the blade in an inclined mode; the distance between a horizontal plane where the airfoil-shaped rotation center of the blade is located and a horizontal plane where the airfoil-shaped rotation center of the blade is located at a position which is 100% of the radius of the propeller from the center of the hub and which is 50% of the radius of the propeller from the center of the hub is 3.0% to 9.3% of the radius of the propeller; the propeller is connected with the driving piece through the propeller hub.

12. The power assembly of claim 11, wherein:

13. The power assembly of claim 11, wherein:

14. The power assembly of claim 13, wherein:

15. The power assembly of claim 13, wherein:

16. The power assembly of claim 15, wherein:

The chord length of the blade is 3.61mm at 120mm from the centre of the hub.

17. The power assembly of claim 11, wherein:

the diameter of the propeller is 240mm +/-24 mm; and/or

The pitch of the blade is 5.36 + -0.5 inches.

18. A power assembly according to any one of claims 11 to 17, wherein:

19. The power assembly of claim 18, wherein:

20. The power assembly of claim 18, wherein:

The suction surface and the pressure surface are both curved surfaces.

21. A power assembly according to any one of claims 11 to 20, wherein the drive member is an electric motor having KV values of 720 ± 72 revolutions/(min-volt).

22. An aircraft is characterized by comprising a fuselage and a power assembly, wherein the power assembly is connected with the fuselage, the power assembly comprises a driving piece and a propeller, the propeller comprises a hub and blades, the blades are connected to the hub, and the blades comprise a root, a tip deviating from the root, a pressure surface and a suction surface opposite to the pressure surface; the blade tip extends towards one side of the pressure surface along the spanwise direction of the blade in an inclined mode; the distance between a horizontal plane where the airfoil-shaped rotation center of the blade is located and a horizontal plane where the airfoil-shaped rotation center of the blade is located at a position which is 100% of the radius of the propeller from the center of the hub and which is 50% of the radius of the propeller from the center of the hub is 3.0% to 9.3% of the radius of the propeller; the propeller is connected with the driving piece through the propeller hub.

23. The aircraft of claim 22, wherein:

24. The aircraft of claim 22, wherein:

25. The aircraft of claim 24, wherein:

26. The aircraft of claim 24, wherein:

27. The aircraft of claim 26, wherein:

The chord length of the blade is 3.61mm at 120mm from the centre of the hub.

28. The aircraft of claim 22, wherein:

the diameter of the propeller is 240mm +/-24 mm; and/or

The pitch of the blade is 5.36 + -0.5 inches.

29. The aircraft according to any one of claims 22 to 28, wherein:

30. The aircraft of claim 29, wherein:

31. The aircraft of claim 29, wherein:

The suction surface and the pressure surface are both curved surfaces.

32. The aircraft according to any one of claims 22 to 31, wherein said drive element is an electric motor having KV values of 720 ± 72 revolutions/(min-volt).

33. The vehicle according to any one of claims 22 to 32, wherein said vehicle comprises a plurality of power modules, said plurality of power modules being rotated in different directions, said vehicle being a multi-rotor vehicle.