A propeller, propeller and unmanned aerial vehicle

Abstract

This utility model discloses a blade, a propeller, and a drone, belonging to the field of aircraft technology. The blade includes a connected root and a blade body. The root has a root centerline, and the distance from the end of the blade furthest from the root to the root centerline is a first length. The blade angle of attack is designed at multiple positions at a distance of the first length from the root centerline. This utility model reduces air resistance and improves aerodynamic efficiency by designing the angle of attack at multiple key positions of the blade. The blade profile is optimized, resulting in lower torque within a higher speed range, thereby reducing the motor's output power and increasing the drone's endurance. The aerodynamic efficiency of the propeller is improved, thus enhancing the drone's flight efficiency.

Description

Technical Field

[0001] This utility model relates to the field of unmanned aerial vehicle (UAV) technology, and in particular to a blade, a propeller, and an UAV. Background Technology

[0002] The propeller is a crucial component of a drone. It converts the engine's power into thrust or lift by rotating its blades in the air, enabling the drone to take off, land, and hover. A propeller typically consists of a hub and blades. The hub is connected to the motor's output shaft via a transmission mechanism. When the motor drives the output shaft to rotate, the hub, connected to the output shaft, also rotates, causing the blades to rotate. This, in turn, creates airflow around the blades, generating lift or thrust for the drone.

[0003] Some drones require long loiter times. For example, remote sensing drones need long loiter times to cover a large area for surveying and aerial photography, while aerial photography drones also require long loiter times for time-lapse photography. In related technologies, the propeller design of drones used for surveying and aerial photography is often flawed, affecting flight efficiency and limiting endurance. Utility Model Content

[0004] The purpose of this utility model embodiment is to provide a blade, a propeller, and a drone, which optimizes the shape of the blade, improves the aerodynamic efficiency of the blade and propeller, improves the flight efficiency of the drone, and increases the drone's endurance.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A blade includes a blade root and a blade body connected together, the blade root having a root centerline, and the distance from the end of the blade away from the blade root to the root centerline is a first length.

[0007] At a position where the distance between the blade and the center line of the root is 19% to 23% of the first length, the angle of attack of the blade is 24.03° ± 2.5°.

[0008] At a position where the distance between the blade and the center line of the root is 49% to 53% of the first length, the angle of attack of the blade is 14.23° ± 2.5°.

[0009] At a position where the distance between the blade and the center line of the root is 82% to 86% of the first length, the angle of attack of the blade is 10.21° ± 2.5°.

[0010] Optionally, at a position where the distance between the blade and the center line of the root is 33% to 37% of the first length, the angle of attack of the blade is 18.21° ± 2.5°.

[0011] And / or, at a position where the distance between the blade and the center line of the root is 64% to 68% of the first length, the angle of attack of the blade is 12.08° ± 2.5°.

[0012] Optionally, at a position where the distance between the blade and the center line of the root is 21% to 22% of the first length, the angle of attack of the blade is 24.03° ± 1°.

[0013] And / or, at a position where the distance between the blade and the center line of the root is 35% to 36% of the first length, the angle of attack of the blade is 18.21° ± 1°;

[0014] And / or, at a position where the distance between the blade and the center line of the root is 51% to 52% of the first length, the angle of attack of the blade is 14.23° ± 1°.

[0015] And / or, at a position where the distance from the blade to the centerline of the root is 66% to 67% of the first length, the angle of attack of the blade is 12.08° ± 1°.

[0016] And / or, at a position where the distance between the blade and the center line of the root is 84% ​​to 85% of the first length, the angle of attack of the blade is 10.21° ± 1°.

[0017] Optionally, at a position where the distance between the blade and the center line of the root is 21% to 22% of the first length, the angle of attack of the blade is 24.03° ± 0.5°.

[0018] And / or, at a position where the distance between the blade and the center line of the root is 35% to 36% of the first length, the angle of attack of the blade is 18.21° ± 0.5°.

[0019] And / or, at a position where the distance between the blade and the center line of the root is 51% to 52% of the first length, the angle of attack of the blade is 14.23° ± 0.5°;

[0020] And / or, at a position where the distance from the blade to the centerline of the root is 66% to 67% of the first length, the angle of attack of the blade is 12.08° ± 0.5°.

[0021] And / or, at a position where the distance between the blade and the center line of the root is 84% ​​to 85% of the first length, the angle of attack of the blade is 10.21° ± 0.5°.

[0022] Optionally, the blade has a first position, a second position, and a third position;

[0023] The distance from the first position of the blade to the center line of the root is 19% to 23% of the first length; the distance from the second position of the blade to the center line of the root is 49% to 53% of the first length; and the distance from the third position of the blade to the center line of the root is 82% to 86% of the first length.

[0024] At the first position of the blade, the angle of attack of the blade is 24.03°±2.5°, and the chord length of the blade is 24.10mm±10m;

[0025] At the second position of the blade, the angle of attack of the blade is 14.23°±2.5°, and the chord length of the blade is 19.97mm±10mm;

[0026] At the third position of the blade, the angle of attack of the blade is 10.21°±2.5°, and the chord length of the blade is 13.22mm±10mm.

[0027] Optionally, the blade has a fourth position and a fifth position; the first position, the fourth position, the second position, the fifth position, and the third position are distributed sequentially.

[0028] The distance from the fourth position of the blade to the center line of the root is 33% to 37% of the first length; the distance from the fifth position of the blade to the center line of the root is 64% to 68% of the first length.

[0029] At the fourth position of the blade, the angle of attack of the blade is 18.21°±2.5°, and the chord length of the blade is 22.66mm±10mm.

[0030] At the fifth position of the blade, the angle of attack of the blade is 12.08°±2.5°, and the chord length of the blade is 16.78mm±10mm.

[0031] Optionally, at the first position of the blade, the distance D1 from the center line of the root of the blade is 24.62 mm, the chord length L1 of the blade is 24.10 mm ± 3 mm, and the angle of attack α1 of the blade is 24.03° ± 0.5°.

[0032] And / or, at the fourth position of the blade, the distance D2 from the center line of the root of the blade is 40.57 mm, the chord length of the blade is L2 = 22.66 mm ± 3 mm, and the angle of attack of the blade is α2 = 18.21° ± 0.5°.

[0033] And / or, at the second position of the blade, the distance D3 from the center line of the root of the blade is 57.72 mm, the chord length of the blade is L3 = 19.97 mm ± 3 mm, and the angle of attack of the blade is α3 = 14.23° ± 0.5°.

[0034] And / or, at the fifth position of the blade, the distance D4 from the center line of the root of the blade is 75.51 mm, the chord length of the blade is L4 = 16.78 mm ± 3 mm, and the angle of attack of the blade is α4 = 12.08° ± 0.5°.

[0035] And / or, at the third position of the blade, the distance D5 from the center line of the root of the blade is 95.04 mm, the chord length of the blade is L5 = 13.22 mm ± 3 mm, and the angle of attack of the blade is α5 = 10.21° ± 0.5°.

[0036] A propeller includes a hub and at least two blades as described above, wherein the root of each blade is connected to the hub.

[0037] Optionally, the length of the blade is between 4 and 5 inches; and / or, the diameter of the propeller is between 8.5 and 10.5 inches.

[0038] An unmanned aerial vehicle (UAV) includes a fuselage and a power unit mounted on the fuselage;

[0039] The power unit includes a drive unit and a propeller as described above. The drive unit is connected to the propeller and is used to drive the propeller to rotate.

[0040] Optionally, the drone is an aerial photography drone, which includes a shooting device mounted on the fuselage.

[0041] The beneficial effects of this utility model are as follows: the blade of this utility model, through the design of the angle of attack at multiple key positions of the blade, reduces air resistance and improves aerodynamic efficiency.

[0042] The propeller and drone of this invention adopt the aforementioned blades, and the blade shape is optimized. The blades have a small torque in a high speed range, thereby reducing the output power of the motor and increasing the flight time of the drone. The aerodynamic efficiency of the propeller is improved, and the flight efficiency of the drone is improved. Attached Figure Description

[0043] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0044] Figure 1 This is one of the structural schematic diagrams of the blade described in the embodiment of this utility model;

[0045] Figure 2 This is a second schematic diagram of the blade structure described in an embodiment of the present utility model;

[0046] Figure 3 This is the third schematic diagram of the blade structure described in the embodiment of this utility model;

[0047] Figure 4 for Figure 3 The first, third, second, fourth, and fifth positions in the diagram correspond to the A-A section, BB section, CC section, DD section, and EE section, respectively.

[0048] Figure 5 This is a partial structural diagram of the propeller described in an embodiment of the present invention.

[0049] In the diagram: 10. Blade body; 11. Connecting part; 12. Main body; 13. Leading edge; 14. Trailing edge; 101. First position; 102. Fourth position; 103. Second position; 104. Fifth position; 105. Third position; 20. Blade root; 21. Root centerline; 22. Rotating shaft hole; 30. Blade tip; 40. Blade hub; 41. Hub centerline. Detailed Implementation

[0050] To make the technical problems solved by this utility model, the technical solutions adopted, and the technical effects achieved clearer, the technical solutions of the embodiments of this utility model will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0051] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected" and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0052] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0053] In related technologies, a propeller includes at least two blades, and when the propeller rotates, the multiple rotating blades form a propeller disk plane. The aerodynamic efficiency of a propeller blade refers to the ratio of the work done by the blade on the air per unit time to the power of the blade; it reflects the blade's energy utilization efficiency and is generally evaluated by the thrust achievable at a given shaft power. The blade profile affects aerodynamic efficiency, and thus the flight efficiency of the UAV.

[0054] Some drones require long loiter times. For example, remote sensing drones need long loiter times to cover a large area for surveying and aerial photography, while aerial photography drones also require long loiter times for time-lapse photography. In related technologies, the propeller design of drones used for surveying and aerial photography still has room for optimization, as their flight efficiency and endurance are limited.

[0055] For drones with propeller diameters between 6 inches and 12 inches, there is a need for propeller optimization. The diameter of a propeller refers to the diameter of the propeller disk plane. The propeller disk is the circular surface within the propeller plane, with the midpoint of the propeller as the center and the radius of the propeller as the radius. In other words, it is the plane formed by the rotating rotor blades of the drone during flight.

[0056] This application optimizes the power system of the UAV, especially the blades and propellers, to improve flight efficiency, achieve longer loiter time, and meet the higher demands of surveying UAVs and aerial photography UAVs.

[0057] This application provides a blade and a propeller. The blade profile is controlled in the radial direction by the chord length and angle of attack at multiple corresponding cross-sectional positions, thereby optimizing the blade profile of the main body 12 of the blade body 10, reducing air resistance, and improving the aerodynamic efficiency of the blade during use. The structural strength of the blade is improved, making it less prone to deformation. This blade and propeller have the advantages of high aerodynamic efficiency, light weight, and high strength, which helps to improve the quality of surveying and aerial photography.

[0058] This application also provides a drone using the aforementioned blades and propellers. Under the same total power, the drone can extend its flight time due to the improved aerodynamic efficiency and the increased energy utilization of the propeller. The higher the aerodynamic efficiency and the longer the flight time, the better the drone's performance in surveying or aerial photography.

[0059] This drone can be, but is not limited to, a mapping drone or an aerial photography drone. The propellers, driven by motors, rotate to generate wind to provide lift. The drone is a quadcopter, enabling efficient flight. In other embodiments, the drone may have three, five, six, or other rotors.

[0060] The blades, propellers, and drones of this utility model will be described in detail below with reference to the accompanying drawings. Unless otherwise specified, the features in the following embodiments and implementation methods can be combined with each other.

[0061] The terms "up" and "down" used in this embodiment refer to the propeller after it is installed on the UAV and the UAV's normal operating attitude, and should not be considered restrictive.

[0062] Please continue to refer to Figures 1 to 5 In an embodiment of the propeller of this utility model, the propeller includes a hub 40 and multiple blades. The figure illustrates a propeller with two blades.

[0063] In one embodiment, the propeller diameter (i.e., the diameter of the propeller disk plane) is 8.5 inches to 10.5 inches, particularly 9 inches to 10 inches. The propeller diameter can be, but is not limited to, 8.5 inches, 9 inches, 9.5 inches, 10 inches, and 10.5 inches. One inch equals 25.4 millimeters.

[0064] In one embodiment, the blade length is 4 to 5 inches, and the blade length can be, but is not limited to, 4 inches, 4.2 inches, 4.4 inches, 4.6 inches, 4.8 inches, or 5 inches.

[0065] Please refer to Figures 1 to 3 The blade includes a blade root 20, a blade body 10, and a blade tip 30. The blade body 10 includes a connecting part 11 and a main body 12. Along the length direction, the blade root 20, the blade body 10 connecting part 11, the blade body 10 main body 12, and the blade tip 30 are connected in sequence. The blade root 20 is used to connect with the blade hub 40. The blade body 10 is the part that mainly provides propulsion or lift.

[0066] In this embodiment, as Figure 2As illustrated, the thickness of the blade root 20 is greater than the thickness of the main body 12 of the blade body 10 to ensure a reliable connection between the blade root 20 and the blade hub 40, guaranteeing the structural strength of the blade root 20, and reliably transmitting torque to achieve blade rotation. Furthermore, the blade smoothly transitions between the blade root 20 and the main body 12 of the blade body 10 via the blade body 10 connecting portion 11, maintaining a certain thickness at the connection point. This effectively solves the problem of blade deformation at the root of the blade root 20 during production and use, and addresses the issue of high stress and easy breakage at the root of the blade root 20 under high speed and high vibration.

[0067] The inventors discovered that the aerodynamic efficiency of a propeller is related to the angle of attack and chord length of its blades. In a propeller, the shape and structure of the blades directly affect the direction and magnitude of the thrust generated during rotation. Therefore, please refer to... Figure 3 , Figure 4 The larger blades are controlled along their length by managing the chord length and angle of attack at more than 10 key locations on the blade body, thereby controlling the overall blade profile and achieving better aerodynamic efficiency.

[0068] Angle of attack, also known as the angle of attack, is the angle between the direction of the incoming wind and the chord line of the blade. The blade consists of two sides forming a suction surface and a pressure surface. The larger the angle of attack, the greater the degree of twist and tilt of the blade at that position, making it easier to draw in air. The side edge where the suction and pressure surfaces connect is called the leading edge 13, and the other side edge is called the trailing edge 14. The leading edge 13 is the side facing the wind, and the arched part of the leading edge 13 facilitates air intake.

[0069] In this invention, the angle of attack design of the three positions 101, 103, and 105 of the propeller body 10 controls the propeller shape. The first position 101 is located at the center of the root of the propeller root 20, and the third position 105 is located at a certain distance from the tip of the propeller 30. The first position 101, the second position 103, and the third position 105 correspond to the front, middle, and rear positions of the main body 12 of the propeller body 10, respectively. By controlling the angle of attack and chord length of the propeller blades in the front, middle, and rear regions, the aerodynamic efficiency of the propeller shape can be controlled.

[0070] To facilitate the description of the parameter design at each position of the blade, the root centerline 21 of the blade root 20 will be used as a reference for explanation. Specifically, the blade root 20 has a root centerline 21. When the blade is installed to the blade hub 40, the root centerline 21 is the installation center. The distance from the end of the blade furthest from the blade root 20 to the root centerline 21 is the first length D0. Figure 1 The diagram illustrates D0. It is understood that the blade length is generally greater than the D0 value; the propeller diameter is generally greater than or equal to the length of two blades. In some embodiments, this is 113 mm to 123 mm.

[0071] It should be noted that in this application, "±" refers to the range of y when x is y±z, z is the range of y's fluctuation, yz≤x≤y+z, and both y and z are positive numbers.

[0072] The distance from the first position 101 of the blade to the root centerline 21 is 19% to 23% of the first length.

[0073] The distance from the second position 103 of the blade to the root centerline 21 is 49% to 53% of the first length.

[0074] The distance from the third position 105 of the blade to the root centerline 21 is 82% to 86% of the first length.

[0075] At the first position 101 of the blade, the angle of attack of the blade is 24.03°±2.5°.

[0076] At the second position 103 of the blade, the angle of attack of the blade is 14.23°±2.5°.

[0077] At position 105 on the third position of the blade, the angle of attack of the blade is 10.21°±2.5°.

[0078] At the first position 101 of the blade, the chord length of the blade is 24.10mm ± 10mm.

[0079] At the second position 103 of the blade, the chord length of the blade is 19.97mm ± 10mm.

[0080] At position 105 on the third blade, the chord length of the blade is 13.22 mm ± 10 mm.

[0081] In one embodiment, the first position 101 of the blade is 21% to 22% of the first length from the root centerline 21. The second position 103 of the blade is 51% to 52% of the first length from the root centerline 21. The third position 105 of the blade is 84% ​​to 85% of the first length from the root centerline 21.

[0082] In one embodiment, the distance from the first position 101 of the blade to the root centerline 21 is 21.80% of the first length, the distance from the second position 103 of the blade to the root centerline 21 is 51.11% of the first length, and the distance from the third position 105 of the blade to the root centerline 21 is 84.15% of the first length.

[0083] In one embodiment, at the first position 101 of the blade, the angle of attack is 24.03°±1°. At the second position 103 of the blade, the angle of attack is 14.23°±1°. At the third position 105 of the blade, the angle of attack is 10.21°±1°.

[0084] In one embodiment, at the first position 101 of the blade, the angle of attack is 24.03° ± 0.5°. At the second position 103 of the blade, the angle of attack is 14.23° ± 0.5°. At the third position 105 of the blade, the angle of attack is 10.20° ± 0.5°.

[0085] In one embodiment, at the first position 101 of the blade, the chord length of the blade is 24.10 mm ± 5 mm. At the second position 103 of the blade, the chord length of the blade is 19.97 mm ± 5 mm. At the third position 105 of the blade, the chord length of the blade is 13.22 mm ± 5 mm.

[0086] In one embodiment, at the first position 101 of the blade, the chord length of the blade is 24.3 mm ± 3 mm. At the second position 103 of the blade, the chord length of the blade is 19.97 mm ± 3 mm. At the third position 105 of the blade, the chord length of the blade is 13.22 mm ± 3 mm.

[0087] In one embodiment, at the first position 101 of the blade, the chord length of the blade is 24.2 mm ± 2 mm. At the second position 103 of the blade, the chord length of the blade is 19.97 mm ± 2 mm. At the third position 105 of the blade, the chord length of the blade is 13.22 mm ± 2 mm.

[0088] By providing a more precise chord length floating range and a more precise angle of attack floating range, it is possible to more accurately control the blade profile of propellers with a diameter of 8.5 inches to 10.5 inches, which are not large, resulting in better aerodynamic efficiency.

[0089] For example, Figure 3 , Figure 4 In the diagram, the A-A section is located at position 101, the CC section is located at position 103, and the EE section is located at position 105.

[0090] Referring to the attached diagram and based on the previous description of the layout of the first position 101 to the third position 105, it can be understood that the first position 101 is a certain distance from the center of the root of the propeller root 20, and the third position 105 is a certain distance from the end of the propeller tip 30. The first position 101, the second position 103, and the third position 105 correspond to the front, middle, and rear positions of the main body 12 of the propeller body 10. By controlling the angle of attack and chord length of the propeller body 10 in the front, middle, and rear regions, the efficiency of propeller shape control can be improved.

[0091] From the first position 101 towards the direction away from the center, the angle of attack of the blades gradually decreases, and the chord length of the blades gradually decreases. By coordinating the chord length and angle of attack at the first position 101, the second position 103, and the third position 105, air can be easily drawn in at the point of maximum angle of attack between the connecting part 11 and the main body 12, thereby improving aerodynamic efficiency.

[0092] The blade of this application is also designed with angle of attack and chord length at a fourth position 102 between the first position 101 and the second position 103, in order to control the propeller profile of the front half of the blade body 10.

[0093] The distance from the fourth position 102 of the blade to the root centerline 21 is 33% to 37% of the first length.

[0094] At position 102 of the fourth position on the blade, the angle of attack of the blade is 18.21°±2.5°.

[0095] At position 102 of the fourth position on the blade, the chord length of the blade is 22.66 mm ± 10 mm.

[0096] In one embodiment, the distance of the fourth position 102 of the blade from the root centerline 21 is 35% to 36% of the first length. In another embodiment, the distance of the fourth position 102 of the blade from the root centerline 21 is 35.92% of the first length.

[0097] In one embodiment, at the fourth position 102 of the blade, the angle of attack of the blade is 18.21°±1°. In another embodiment, at the fourth position 102 of the blade, the angle of attack of the blade is 18.21°±0.5°.

[0098] In one embodiment, at the fourth position 102 of the blade, the chord length of the blade is 22.66 mm ± 5 mm. In another embodiment, at the fourth position 102 of the blade, the chord length of the blade is 22.66 mm ± 3 mm. In yet another embodiment, at the fourth position 102 of the blade, the chord length of the blade is 22.66 mm ± 2 mm.

[0099] By providing a more precise chord length floating range and a more precise angle of attack floating range, it is possible to more accurately control the blade profile of propellers with a diameter of 8.5 inches to 10.5 inches, which are not large, resulting in better aerodynamic efficiency.

[0100] For example, Figure 3 , Figure 4 In the middle, the BB section is located at position 102, which is the fourth position.

[0101] By designing the angle of attack and chord length of the first position 101, the fourth position 102, and the second position 103, the front half of the main body 12 of the propeller 10 can be designed to easily take in wind and efficiently utilize wind power to achieve lift, thereby improving aerodynamic efficiency.

[0102] The blade of this application is also designed with angle of attack and chord length at the fifth position 104 between the second position 103 and the third position 105, in order to control the propeller profile of the rear half of the blade body 10.

[0103] The distance from the fifth position 104 of the blade to the root centerline 21 is 64% to 68% of the first length.

[0104] At position 104 on the fifth position of the blade, the angle of attack of the blade is 12.08°±2.5°.

[0105] At position 104 of the fifth position on the blade, the chord length of the blade is 16.78 mm ± 10 mm.

[0106] In one embodiment, the distance from the fifth position 104 of the blade to the root centerline 21 is 66% to 67% of the first length. In another embodiment, the distance from the fifth position 104 of the blade to the root centerline 21 is 66.86% of the first length.

[0107] In one embodiment, at the fifth position 104 of the blade, the angle of attack of the blade is 12.08°±1°. In another embodiment, at the fifth position 104 of the blade, the angle of attack of the blade is 12.08°±0.5°.

[0108] In one embodiment, at the fifth position 104 of the blade, the chord length of the blade is 16.78 mm ± 5 mm. In another embodiment, at the fifth position 104 of the blade, the chord length of the blade is 16.78 mm ± 3 mm. In yet another embodiment, at the fifth position 104 of the blade, the chord length of the blade is 16.78 mm ± 2 mm.

[0109] By providing a more precise chord length floating range and a more precise angle of attack floating range, it is possible to more accurately control the blade profile of propellers with a diameter of 8.5 inches to 10.5 inches, which are not large, resulting in better aerodynamic efficiency.

[0110] For example, Figure 3 , Figure 4 In the middle, the DD section is located at position 104, which is the fifth position.

[0111] By designing the angle of attack and chord length at the second position 103, the fifth position 104, and the third position 105, the rear half of the main body 12 of the propeller 10 can be designed to be relatively gentle, reducing wind resistance and improving aerodynamic efficiency.

[0112] Please refer to Figure 3 This provides a specific method for setting the blade profile:

[0113] When the propeller blade is at a section (A-A section) at a distance of 21 from the root centerline and a distance of D1 = 24.62 mm, the chord length L1 = 24.10 mm ± 5 mm and the angle of attack α1 = 24.03° ± 2.5°.

[0114] When the propeller blade is at a section (BB section) at a distance of 21 from the root centerline and a distance of D2 = 40.57 mm, the chord length L2 = 22.66 mm ± 5 mm and the angle of attack α2 = 18.21° ± 2.5°.

[0115] When the propeller blade is at a section (CC section) with a distance of 21 from the root centerline and a distance of D3 = 57.72 mm, the chord length L3 = 19.97 mm ± 5 mm and the angle of attack α3 = 14.23° ± 2.5°.

[0116] When the propeller blade is at a section (DD section) at a distance of 21 from the root centerline and a distance of D4 = 75.51 mm, the chord length L4 = 16.78 mm ± 5 mm and the angle of attack α4 = 12.08° ± 2.5°.

[0117] When the propeller blade is at a distance of 21 from the root centerline and at a section D5 = 95.04 mm (EE section), the chord length L5 = 13.22 mm ± 5 mm and the angle of attack α5 = 10.21° ± 2.5°.

[0118] Please refer to Figure 3 This provides another specific configuration method for the blade profile:

[0119] When the propeller blade is at a section (A-A section) at a distance of 21 from the root centerline and a distance of D1 = 24.62 mm, the chord length L1 = 24.10 mm ± 3 mm and the angle of attack α1 = 24.03° ± 1°.

[0120] When the propeller blade is at a section (BB section) at a distance of 21 from the root centerline and a distance of D2 = 40.57 mm, the chord length L2 = 22.66 mm ± 3 mm and the angle of attack α2 = 18.21° ± 1°.

[0121] When the propeller blade is at a section (CC section) with a distance of 21 from the root centerline and a distance of D3 = 57.72 mm, the chord length L3 = 19.97 mm ± 3 mm and the angle of attack α3 = 14.23° ± 1°.

[0122] When the propeller blade is at a section (DD section) at a distance of 21 from the root centerline and a distance of D4 = 75.51 mm, the chord length L4 = 16.78 mm ± 3 mm and the angle of attack α4 = 12.08° ± 1°.

[0123] When the propeller blade is at a distance of 21 from the root centerline and at a section D5 = 95.04 mm (EE section), the chord length L5 = 13.22 mm ± 3 mm and the angle of attack α5 = 10.21° ± 1°.

[0124] In one embodiment, the propeller blades are configured with the angle of attack and / or chord length scheme of this application at the aforementioned first position 101, second position 103, third position 105, fourth position 102, and fifth position 104. In another embodiment, the propeller blades are configured with the angle of attack and / or chord length scheme of this application only at the aforementioned first position 101, second position 103, and third position 105. In yet another embodiment, the propeller blades are configured with the angle of attack and / or chord length scheme of this application only at the aforementioned first position 101, second position 103, third position 105, and fourth position 102. In yet another embodiment, the propeller blades are configured with the angle of attack and / or chord length scheme of this application only at the aforementioned first position 101, second position 103, third position 105, and fifth position 104.

[0125] To verify the aerodynamic efficiency of the propeller blade of this invention, the inventors conducted an aerodynamic efficiency experiment. The propeller of this invention can effectively increase lift and reduce the required shaft power to achieve the same thrust. In other words, it can achieve greater thrust with the same power, or reduce the power of the drive mechanism to meet the same thrust requirements.

[0126] The experimental data for the propeller of this application are provided below.

[0127]

[0128] In one embodiment, the top and bottom of the propeller root 20 are set as planes to facilitate installation and mating with the propeller hub 40. In this embodiment, a first root plane and a second root plane are formed on both sides of the propeller root 20 to provide a mating plane for the propeller root 20 and the propeller hub 40.

[0129] In one embodiment, the connecting portion 11 of the propeller body 10 provides a smooth transition between the propeller root 20 and the main body 12 of the propeller body 10, making it less prone to breakage. Since both the upper and lower surfaces of the propeller root 20 are parallel to the reference horizontal plane, the propeller shape of the connecting portion 11 can be controlled by varying the angle of attack of the connecting portion 11. This ensures a smooth connection between the upper surface of the propeller root 20 and the upper surface of the connecting portion 11, and a smooth connection between the lower surface of the propeller root 20 and the lower surface of the connecting portion 11, avoiding significant step differences between the propeller root 20 and the connecting portion 11. This reduces air resistance experienced by the connecting portion 11 during propeller rotation, prevents stress concentration, and improves the overall structural strength of the propeller blade. Furthermore, the angle of attack of the connecting portion 11 gradually changes along the length of the propeller blade, preventing sudden bulges or depressions in the middle section of the connecting portion 11 and avoiding localized stress concentration. The propeller blade of this invention is less prone to deformation and breakage, exhibiting high structural strength.

[0130] In one embodiment, to ensure the structural strength of the blade, the blade root 20, the connecting portion 11 of the blade body 10, and the main body 12 of the blade body 10 are made of the same material, and are integrally formed. The blade root 20 and the blade body 10 can be made of materials such as plastic, carbon fiber, glass, or metal. The blade root 20, blade body 10, and blade tip 30 can be integrally formed using injection molding to create the blade.

[0131] In one embodiment, the propeller root 20 is connected to the propeller hub 40 by fasteners or other connection methods. In other embodiments, the propeller blade and the propeller hub 40 may also be integrally formed.

[0132] In one embodiment, the propeller includes two blades symmetrically mounted on a hub 40. The hub 40 has a hub centerline 41, and the rotation center of the blades is the hub centerline 41. The root centerlines 21 of the two blades are symmetrical with respect to the hub centerline 41. The rotation radius of the blades is the distance between the end of the blade furthest from the hub 40 and the hub center of the hub 40.

[0133] In other embodiments, the number of propeller blades may be three, four, or others. The figure illustrates that the propeller root 20 is provided with a rotating shaft hole 22. The propeller root 20 can be mounted on the propeller hub 40 by passing a mounting shaft through the rotating shaft hole 22. The centerline of the rotating shaft hole 22 is the root centerline 21.

[0134] In one embodiment of the unmanned aerial vehicle (UAV) of this invention, the UAV includes a fuselage and a power unit. The power unit includes a drive unit and a propeller as described in any of the foregoing embodiments, and the power unit is mounted on the fuselage. The power unit provides flight power to the fuselage.

[0135] The drive unit is connected to the propeller and is used to drive the propeller to rotate in order to provide flight power.

[0136] The drive device can be, but is not limited to, an electric motor. The motor shaft is connected to the propeller hub 40, and the motor shaft drives the propeller hub 40 to rotate, thereby realizing the rotation of the propeller.

[0137] In one embodiment, the drone is an aerial photography drone, and the drone includes a shooting device mounted on the fuselage.

[0138] The blades can be manufactured using any material available in the prior art, including but not limited to plastics, steel, aluminum alloys, and carbon fiber. During manufacturing, various existing processing techniques, such as molding, stamping, and forging, can also be employed.

[0139] In the description herein, it should be understood that the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationships shown in the accompanying drawings, and are used only for ease of description and simplification of operation. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first" and "second" are merely used for distinction in description and have no special meaning.

[0140] In the description of this specification, references to terms such as "an embodiment," "example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.

[0141] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style of the specification is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0142] The technical principles of this utility model have been described above with reference to specific embodiments. These descriptions are merely for explaining the principles of this utility model and should not be construed as limiting the scope of protection of this utility model in any way. Based on this explanation, those skilled in the art can readily conceive of other specific embodiments of this utility model without any inventive effort, and these embodiments will all fall within the scope of protection of this utility model.

Claims

1. A paddle, characterized in that, It includes a connected blade root (20) and blade body (10), the blade root (20) has a root centerline (21), and the distance from the end of the blade away from the blade root (20) to the root centerline (21) is a first length; At a position where the distance between the blade and the root centerline (21) is 19% to 23% of the first length, the angle of attack of the blade is 24.03° ± 2.5°. At a position where the distance between the blade and the root centerline (21) is 49% to 53% of the first length, the angle of attack of the blade is 14.23° ± 2.5°. At a position where the distance between the blade and the root centerline (21) is 82% to 86% of the first length, the angle of attack of the blade is 10.21° ± 2.5°.

2. The paddle of claim 1, wherein At a position where the distance between the blade and the root centerline (21) is 33% to 37% of the first length, the angle of attack of the blade is 18.21° ± 2.5°. And / or, at a position where the blade is 64% to 68% of the first length from the root centerline (21), the blade has an angle of attack of 12.08° ± 2.5°.

3. The paddle of claim 1, wherein, At a position where the distance between the blade and the root centerline (21) is 21% to 22% of the first length, the angle of attack of the blade is 24.03° ± 1°. And / or, at a position where the blade is 35% to 36% of the first length from the root centerline (21), the angle of attack of the blade is 18.21° ± 1°. And / or, at a position where the blade is at a distance of 51% to 52% of the first length from the root centerline (21), the angle of attack of the blade is 14.23° ± 1°. And / or, at a position where the blade is at a distance of 66% to 67% of the first length from the root centerline (21), the angle of attack of the blade is 12.08° ± 1°. And / or, at a position where the blade is at a distance of 84% to 85% of the first length from the root centerline (21), the blade has an angle of attack of 10.21° ± 1°.

4. The paddle of claim 1, wherein At a position where the distance between the blade and the root centerline (21) is 21% to 22% of the first length, the angle of attack of the blade is 24.03° ± 0.5°. And / or, at a position where the blade is 35% to 36% of the first length from the root centerline (21), the angle of attack of the blade is 18.21° ± 0.5°. And / or, at a position where the blade is at a distance of 51% to 52% of the first length from the root centerline (21), the angle of attack of the blade is 14.23° ± 0.5°. And / or, at a position where the blade is at a distance of 66% to 67% of the first length from the root centerline (21), the angle of attack of the blade is 12.08° ± 0.5°. And / or, at a position where the blade is at a distance of 84% to 85% of the first length from the root centerline (21), the blade has an angle of attack of 10.21° ± 0.5°.

5. The paddle according to any one of claims 1-4, characterized in that The blade has a first position (101), a second position (103) and a third position (105); The distance from the first position (101) of the blade to the root centerline (21) is 19% to 23% of the first length; the distance from the second position (103) of the blade to the root centerline (21) is 49% to 53% of the first length; the distance from the third position (105) of the blade to the root centerline (21) is 82% to 86% of the first length. At the first position (101) of the blade, the angle of attack of the blade is 24.03°±2.5°, and the chord length of the blade is 24.10mm±10m; At the second position (103) of the blade, the angle of attack of the blade is 14.23°±2.5°, and the chord length of the blade is 19.97mm±10mm; At the third position (105) of the blade, the angle of attack of the blade is 10.21°±2.5° and the chord length of the blade is 13.22mm±10mm.

6. The paddle of claim 5, wherein, The blade has a fourth position (102) and a fifth position (104); the first position (101), the fourth position (102), the second position (103), the fifth position (104), and the third position (105) are distributed in sequence; The distance from the fourth position (102) of the blade to the root centerline (21) is 33% to 37% of the first length; the distance from the fifth position (104) of the blade to the root centerline (21) is 64% to 68% of the first length. At the fourth position (102) of the blade, the angle of attack of the blade is 18.21°±2.5°, and the chord length of the blade is 22.66mm±10mm; At the fifth position (104) of the blade, the angle of attack of the blade is 12.08°±2.5° and the chord length of the blade is 16.78mm±10mm.

7. The paddle according to any one of claims 1-4, wherein, At the first position (101) of the blade, the distance D1 from the root centerline (21) of the blade is 24.62 mm, the chord length of the blade is L1 = 24.10 mm ± 3 mm, and the angle of attack of the blade is α1 = 24.03° ± 0.5°. And / or, at the fourth position (102) of the blade, the distance D2 from the root centerline (21) of the blade is 40.57 mm, the chord length of the blade is L2 = 22.66 mm ± 3 mm, and the angle of attack of the blade is α2 = 18.21° ± 0.5°. And / or, at the second position (103) of the blade, the distance D3 from the root centerline (21) of the blade is 57.72 mm, the chord length of the blade is L3 = 19.97 mm ± 3 mm, and the angle of attack of the blade is α3 = 14.23° ± 0.5°; And / or, at the fifth position (104) of the blade, the distance D4 from the root centerline (21) of the blade is 75.51 mm, the chord length of the blade is L4 = 16.78 mm ± 3 mm, and the angle of attack of the blade is α4 = 12.08° ± 0.5°. And / or, at the third position (105) of the blade, the distance D5 from the root centerline (21) of the blade is 95.04 mm, the chord length of the blade is L5 = 13.22 mm ± 3 mm, and the angle of attack of the blade is α5 = 10.21° ± 0.5°.

8. A propeller, characterized in that It includes a hub (40) and at least two blades as described in any one of claims 1-7, wherein the root (20) of each blade is connected to the hub (40).

9. The propeller of claim 8, wherein, The blades are between 4 and 5 inches in length; and / or the propeller is between 8.5 and 10.5 inches in diameter.

10. A drone, characterized in that, Includes the fuselage and the power unit installed on the fuselage; The power unit includes a drive unit and a propeller as described in claim 8 or 9, wherein the drive unit is connected to the propeller and is used to drive the propeller to rotate.

11. The drone of claim 10, wherein, The drone is an aerial photography drone, which includes a shooting device mounted on the fuselage.

Images