High-efficiency low-noise propeller and mounting assembly for unmanned aerial vehicles

Abstract

The utility model relates to unmanned plane technical field discloses a kind of high-efficiency low-noise propeller and mounting assembly for unmanned plane, including helical blade and paddle wheel, the helical blade one end is fixedly connected in the paddle wheel side wall, the helical blade is evenly distributed along the paddle wheel circumference, and the helical blade quantity is set to five, the mounting hole is opened in the paddle wheel center, two locating holes are opened in the paddle wheel inside, the motor base is set in paddle wheel bottom, the motor base inside rotationally connected has rotary seat, the rotary seat upper portion is provided with mounting structure. In the utility model, by helical blade using progressive torsion angle design, cooperate with leading edge arc transition and rear edge reduction formula design, reduce airflow separation, by helical blade surface setting polytetrafluoroethylene modification noise reduction coating, drive airflow and blade interfacial friction coefficient reduction, reduce eddy current noise, reach the effect of low-noise operation, realize the dual promotion of unmanned plane high-efficiency propulsion and low-noise operation by above-mentioned structure.

Description

Technical Field

[0001] This utility model relates to the field of unmanned aerial vehicle (UAV) technology, and in particular to a high-efficiency, low-noise propeller and mounting assembly for UAVs. Background Technology

[0002] In the field of small drones, the propeller, as the core power output component, directly determines the drone's flight efficiency, endurance, and adaptability to various application scenarios. With the widespread application of drones in aerial surveying, agricultural plant protection, and indoor inspection, the market demand for "high-efficiency propulsion" and "low-noise operation" of propellers is becoming increasingly prominent. For example, in agricultural plant protection operations, high-efficiency propellers can improve pesticide spraying coverage, while low-noise designs can reduce interference with the surrounding ecosystem and personnel. In indoor inspection scenarios, low noise can avoid acoustic pollution to the indoor environment, while high-efficiency propulsion ensures flexible endurance of the drone within limited spaces. At the same time, as a vulnerable component, the ease and stability of the propeller's installation structure indirectly affect the drone's maintenance efficiency and flight safety. Therefore, propeller design that balances high efficiency, low noise performance, and a reliable installation structure has become one of the important directions for the optimization of current small drone technology.

[0003] Currently, most small drones use propellers with a 2- or 3-blade structure. The technical principle revolves around "rotating blades cutting through airflow to generate thrust." The blades employ a fixed twist angle design, meaning the twist angle from the center of the rotor to the tip remains consistent to simplify manufacturing. The leading edge of the blades is mostly a straight line or a simple arc, while the trailing edge uses a uniform width structure to reduce design and production complexity. For noise reduction, existing technologies often use lightweight plastic materials to reduce blade vibration noise or optimize blade surface smoothness to reduce airflow friction. Some high-end products employ blade airfoil optimization (such as symmetrical airfoils) to attempt a balance between thrust and noise. Regarding installation, the mainstream solution still relies on screws and washers to fix the propeller rotor to the motor shaft's rotating seat using multiple screws. The threaded fastening force ensures synchronous rotation of the propeller and the rotating seat. Some products add positioning pins to the contact surface between the rotor and the rotating seat to help improve installation coaxiality.

[0004] However, the fixed torsion angle design and simplified leading and trailing edge structure of existing propellers are prone to airflow separation problems in actual operation. When airflow passes over the blade surface, the fixed torsion angle cannot adapt to the airflow conditions at different radii of the blade due to the difference in linear velocity. This causes the airflow to detach from the blade surface at the middle or tip of the blade, forming vortices. At the same time, the equal-width trailing edge exacerbates the turbulence of the airflow at the tail of the blade, further disrupting the airflow continuity. This airflow separation not only causes thrust loss and reduces propeller propulsion efficiency, leading to shorter drone range and reduced payload capacity, but also generates significant aerodynamic noise due to the generation and rupture of vortices. The noise problem is particularly prominent under high-speed rotation conditions, making it difficult to meet the usage requirements of noise-sensitive scenarios such as indoor inspection and close-range plant protection. Therefore, a high-efficiency, low-noise propeller and mounting components for drones are proposed to solve the above problems. Utility Model Content

[0005] To overcome the above shortcomings, this utility model provides a high-efficiency, low-noise propeller and mounting assembly for drones, aiming to improve the problem of excessive noise when existing propellers rotate at high speeds.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A high-efficiency, low-noise propeller for unmanned aerial vehicles includes a propeller blade and a rotor. One end of the propeller blade is fixedly connected to the side wall of the rotor. The propeller blades are evenly distributed around the circumference of the rotor, and the number of propeller blades is set to five. An installation hole is provided in the center of the rotor, and two positioning holes are provided inside the rotor.

[0007] As a further description of the above technical solution: This utility model also provides a high-efficiency, low-noise propeller mounting assembly for drones. The high-efficiency, low-noise propeller mounting assembly for drones includes a motor mount, which is disposed at the bottom of the propeller wheel. A rotating seat is fixedly connected inside the motor mount, and a mounting structure is disposed above the rotating seat. The mounting structure includes a plug rod and two positioning rods. One end of the plug rod and one end of the positioning rod are fixedly connected to the upper surface of the rotating seat. The side wall of the plug rod is slidably connected to the inside of the mounting hole. The side walls of the two positioning rods are slidably connected to the inside of the positioning hole. A pressing block is slidably connected inside the plug rod. A push block is fixedly connected to the bottom of the pressing block. A spring is provided inside the plug rod. One end of the spring is fixedly connected to the inside of the plug rod, and the other end of the spring is fixedly connected to the bottom of the push block. Multiple balls are provided inside the plug rod. The side wall of the plug rod has a receiving cavity that matches the balls. The side wall of the push block has a limiting groove that matches the balls.

[0008] As a further description of the above technical solution: The inner wall of the mounting hole is provided with a groove. The groove is annular and matches the shape of the ball. One side of the ball contacts the side wall of the push block, and the other side of the ball can extend out of the outer wall of the insertion rod and engage with the groove.

[0009] As a further description of the above technical solution: The receiving cavity corresponds to the ball bearing, and the receiving cavity is evenly distributed along the circumference of the insert rod, with a quantity of four. The ball bearing is made of stainless steel, and the outer diameter of the ball bearing is adapted to the diameter of the opening of the receiving cavity.

[0010] As a further description of the above technical solution: The mounting structure also includes a cover, which is semi-circular and detachably connected to the top of the insertion rod via threads, for further locking the propeller.

[0011] As a further description of the above technical solution: The propeller blade adopts a gradually decreasing twist angle design, with the twist angle gradually decreasing along the direction from the center of the propeller to the tip of the propeller blade.

[0012] As a further description of the above technical solution: The leading edge curve of the helical blade adopts a circular arc transition design, and the trailing edge curve adopts a reduced design. The surface of the helical blade is provided with a noise reduction coating, which is a polytetrafluoroethylene modified coating, used to reduce the vortex noise generated by the interaction between the helical blade and the airflow when the helical blade rotates.

[0013] This utility model has the following beneficial effects: 1. In this utility model, the spiral blade adopts a gradual twist angle design, combined with the leading edge arc transition and the trailing edge reduction design, to reduce airflow separation and achieve the effect of improving propulsion efficiency. By setting a polytetrafluoroethylene modified noise reduction coating on the surface of the spiral blade, the friction coefficient between the airflow and the blade is reduced, reducing eddy noise and achieving the effect of low-noise operation. This solves the problem of excessive noise when existing propellers rotate at high speed. The above structure achieves a dual improvement in efficient propulsion and low-noise operation of UAVs.

[0014] 2. In this utility model, precise alignment is achieved by cooperating the positioning rod and the positioning hole. By pressing down the pressing block, the push block is pushed to compress the spring and drive the ball to slide, which enables the propeller to be quickly disassembled and assembled, solving the cumbersome screw fixing. The cover lock prevents accidental contact and solves the risk of loosening due to vibration. The above structure improves the installation efficiency, positioning accuracy and safety of the equipment, while simplifying the maintenance process and improving the overall practicality of the equipment. Attached Figure Description

[0015] Figure 1 This is a perspective view of a high-efficiency, low-noise propeller and its mounting assembly for a drone, as proposed in this utility model. Figure 2 This is a top view of a high-efficiency, low-noise propeller and mounting assembly for a drone proposed in this utility model; Figure 3 This utility model provides a side view of the propeller blade of a high-efficiency, low-noise propeller and mounting assembly for unmanned aerial vehicles. Figure 4 This utility model provides a schematic diagram showing the rotor blade and mounting structure of a high-efficiency, low-noise propeller and mounting assembly for unmanned aerial vehicles. Figure 5 This is a schematic diagram of the installation structure of a high-efficiency, low-noise propeller and mounting components for unmanned aerial vehicles (UAVs) proposed in this utility model. Figure 6 A schematic diagram of the side angle structure of a single helical blade for a high-efficiency, low-noise propeller and mounting components for a drone proposed in this utility model. Figure 7 This invention presents a schematic diagram of a single helical blade and test data of a high-efficiency, low-noise propeller and mounting assembly for unmanned aerial vehicles (UAVs).

[0016] Legend: 1. Propeller blade; 2. Paddle wheel; 3. Motor base; 4. Rotary base; 5. Mounting structure; 501. Insert rod; 502. Positioning rod; 503. Pressing block; 504. Push block; 505. Spring; 506. Ball bearing; 507. Cover; 6. Mounting hole; 7. Positioning hole. Detailed Implementation

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0018] Reference Figure 1 , Figure 3 , Figure 6 and Figure 7 The present invention provides an embodiment of a high-efficiency, low-noise propeller for unmanned aerial vehicles (UAVs), comprising a propeller blade 1 and a rotor 2. One end of the propeller blade 1 is fixedly connected to the side wall of the rotor 2. The propeller blades 1 are evenly distributed around the rotor 2, and the number of propeller blades 1 is set to five. The five propeller blades 1 are evenly distributed around the rotor 2 to form a symmetrical airflow cutting structure. With the special design of the propeller blades 1, the airflow utilization rate can be improved, thereby enhancing the thrust stability. The rotor 2 has a mounting hole 6 in the center, which is used to cooperate with the insertion rod 501 to provide an installation channel for the rotor 2. The rotor 2 has two positioning holes 7 inside to achieve positioning during installation. The propeller blade 1 adopts a gradually decreasing twist angle design, with the twist angle gradually decreasing from the center of the impeller 2 to the tip of the propeller blade 1. This design is used to adapt to the difference in linear velocity at different radii of the propeller blade 1, reduce airflow separation, and improve propulsion efficiency. The leading edge curve of the propeller blade 1 adopts a circular arc transition design, while the trailing edge curve adopts a reduced design. The circular arc transition design at the leading edge is used to reduce the impact intensity of the airflow, while the reduced design at the trailing edge is used to optimize the airflow wake. The two work together to optimize airflow motion and reduce the generation of eddies. The surface of the propeller blade 1 is covered with a noise reduction coating. The noise reduction coating is a polytetrafluoroethylene modified coating with a thickness of 5-10μm. The polytetrafluoroethylene modified coating is a low-friction, high-weather-resistant coating. Its function is to reduce the friction coefficient between the airflow and the surface of the propeller blade 1, reduce friction noise and eddy noise, and reduce the eddy noise generated by the interaction between the propeller blade 1 and the airflow when rotating. The propeller blade 1 employs a gradually decreasing twist angle design, combined with specific airfoil parameters to achieve efficient propulsion and low-noise operation: along the direction from the center of rotor 2 to the tip of propeller blade 1, the twist angle θ gradually decreases. When the distance r from the center of rotation to the airfoil is 7 mm, the twist angle θ is 30.5°; when r is 19 mm, θ is 27°; when r is 30 mm, θ is 20.5°; and when r is 38 mm, θ is 15°. This gradually decreasing twist angle design adapts to the linear velocity differences at different radii of the propeller blade, optimizes the airflow path across the blade surface, and reduces airflow separation.

[0019] The airfoil thickness *c* of propeller blade 1 also exhibits a matching relationship with the chord length *b*. When *r* is 7 mm, the chord length *b* is 9.4 mm and the thickness *c* is 1.88 mm; when *r* is 19 mm, *b* is 15.8 mm and *c* is 2.844 mm; when *r* is 30 mm, *b* is 13.2 mm and *c* is 2.374 mm; and when *r* is 38 mm, *b* is 10.9 mm and *c* is 1.962 mm. The airfoil thickness *c* is 1 / 5 to 1 / 3 of the corresponding chord length *b*, and this design further optimizes aerodynamic efficiency.

[0020] The leading edge of the propeller blade 1 features a circular arc transition design, while the trailing edge adopts a reduced design. Combined with a PTFE-modified noise-reducing coating, this reduces the friction coefficient between the airflow and the blade, thus minimizing vortex noise. The propeller exhibits excellent efficiency under varying thrust levels. At a thrust of 101.3g, the system efficiency reaches 3.92g / W, significantly higher than traditional propellers, while simultaneously reducing noise levels, achieving the dual benefits of high-efficiency propulsion and low-noise operation.

[0021] Reference Figures 4-5Another embodiment of this utility model is provided: a high-efficiency and low-noise propeller mounting component for drones. The high-efficiency and low-noise propeller mounting component for drones includes a motor mount 3, which is located at the bottom of the propeller wheel 2. A rotating seat 4 is fixedly connected inside the motor mount 3. The motor mount 3 is used to fix and install the drive motor of the drone, such as the common brushless DC motor model 2206. This model of motor is widely used in small drones. The rotating seat 4 is used to support the propeller body and the motor power. An installation structure 5 is provided above the rotating seat 4. The mounting structure 5 includes a plug rod 501 and two positioning rods 502. One end of the plug rod 501 and the positioning rods 502 are fixedly connected to the upper surface of the rotating base 4. The side wall of the plug rod 501 is slidably connected inside the mounting hole 6, and the side walls of the two positioning rods 502 are slidably connected inside the positioning holes 7. The plug rod 501 is used to insert into the mounting hole 6 of the propeller wheel 2 to provide an axial mounting reference for the propeller body. The positioning rods 502 are used to cooperate with the positioning holes 7 of the propeller wheel 2 to prevent circumferential deviation when the propeller rotates. The insert rod 501 has a sliding connection to a pressing block 503, and a push block 504 is fixedly connected to the bottom of the pressing block 503. The pressing block 503 is used to receive external pressing force, which drives the push block 504 to slide along the inside of the insert rod 501, thereby controlling the extension and retraction of the ball bearing 506. A spring 505 is installed inside the insert rod 501. One end of the spring 505 is fixedly connected to the inside of the insert rod 501, and the other end of the spring 505 is fixedly connected to the bottom of the push block 504. The spring 505 serves as the push block 504. A reset spring is provided to push the push block 504 upward after the pressing action ends, thereby squeezing the ball 506 out. The spring 505 is made of piano wire, and the spring constant of the spring 505 is such that when the pressing block 503 is subjected to an axial pressure of 5-10N, the spring 505 is compressed by 3-5mm, and the ball 506 can be completely retracted into the receiving cavity; when the pressing block 503 is not under pressure, the spring force of the spring 505 can push the push block 504 to move, and the insert rod 501 inside... The part is provided with multiple balls 506. The side wall of the insertion rod 501 has a receiving cavity that matches the balls 506. The receiving cavity is used to store the balls 506 and provide radial sliding space for the balls 506. The side wall of the push block 504 has a limiting groove that matches the balls 506. The limiting groove is used to limit the balls 506 when they retract into the insertion rod 501 to prevent them from rolling. The balls 506 are used to achieve engagement and fixation or separation between the paddle wheel 2 and the insertion rod 501 through extension or retraction.

[0022] The insert rod 501 is slidably connected to the inside of the mounting hole 6, and the two positioning rods 502 are slidably connected to the inside of the positioning holes 7. Precise alignment is achieved through the cooperation of the insert rod 501 with the mounting hole 6 and the positioning rods 502 with the positioning holes 7, thus preventing the impeller 2 from being installed off-center. A groove is provided on the inner wall of the mounting hole 6. The groove is annular and matches the shape of the ball bearing 506. The groove is used to engage with the ball bearing 506, forming an axial fixing structure. One side of the ball bearing 506 contacts the side wall of the push block 504, and the other side of the ball bearing 506 can extend out of the outer wall of the insert rod 501 and engage with the groove. Engagement is achieved through the cooperation of the push block 504 with the ball bearing 506 and the ball bearing 506 with the groove. The fixed motion achieves the effect of quickly fixing the paddle wheel 2. The receiving cavity corresponds to the ball 506, and the receiving cavities are evenly distributed around the insert rod 501. The number of receiving cavities is set to four. The four receiving cavities and the ball 506 are evenly distributed around the insert rod 501 to form a symmetrical locking force, thereby improving the fixing stability. The ball 506 is made of stainless steel. Stainless steel is a high-strength and corrosion-resistant material. Its function is to ensure that the ball 506 is not easily worn or rusted during long-term use. This is common knowledge and will not be elaborated on here. The outer diameter of the ball 506 is adapted to the diameter of the opening of the receiving cavity. This adaptation design is used to prevent the ball 506 from falling out of the receiving cavity or excessive shaking.

[0023] The mounting structure 5 also includes a cover 507, which is semi-circular and detachably connected to the top of the insert rod 501 via threads. It is used to further lock the propeller wheel 2. The cover 507 engages with the threaded connection of the insert rod 501 to perform a locking motion, thereby preventing the ball bearing 506 from retracting due to accidental contact with the pressing block 503 during flight caused by vibration.

[0024] Working principle: During propeller installation, first align the mounting hole 6 of the propeller wheel 2 with the insertion rod 501 on the rotating seat 4, and at the same time align the two positioning holes 7 of the propeller wheel 2 with the two positioning rods 502 on the rotating seat 4. The positioning rods 502 achieve the initial positioning of the propeller through sliding cooperation with the positioning holes 7, ensuring that the insertion rods 501 and the mounting hole 6 are coaxial.

[0025] Next, press the pressing block 503 at the top of the insertion rod 501. The pressing block 503 pushes the push block 504 at the bottom to slide downward along the inside of the insertion rod 501. At this time, the push block 504 compresses the spring 505 inside the insertion rod 501. The spring 505 is in an energy storage state. During the downward movement of the push block 504, its side wall is separated from the four balls 506 inside the insertion rod 501. Under the action of its own gravity, the balls 506 slide along the receiving cavity into the insertion rod 501 until they are completely retracted into the receiving cavity, thus removing the obstruction to the mounting hole 6 of the propeller wheel 2.

[0026] Then, continue sliding the propeller wheel 2 downwards along the insertion rod 501. When the propeller wheel 2 reaches the installation position, the groove on the inner wall of the mounting hole 6 corresponds to the position of the receiving cavity of the insertion rod 501. At this time, release the pressing block 503, and the spring 505 releases its elastic force to push the push block 504 upwards to reset. The side wall of the push block 504 squeezes the ball 506, causing the ball 506 to slide along the receiving cavity to the outside of the insertion rod 501. Finally, it extends out of the outer wall of the insertion rod 501 and is inserted into the groove of the mounting hole 6, thus achieving axial fixation between the propeller wheel 2 and the rotating seat 4. After installation, fix the cover 507 to the top of the insertion rod 501 through a threaded connection. The cover 507 further locks the propeller wheel 2 to prevent the pressing block 503 from being accidentally activated due to vibration during flight.

[0027] When the drone is working, the motor drives the rotating seat 4 inside the motor base 3 to rotate. The rotating seat 4 drives the propeller wheel 2 and the propeller blade 1 to rotate synchronously through the engagement structure of the insert rod 501 and the ball 506. The cooperation between the positioning rod 502 and the positioning hole 7 can help transmit torque and prevent the ball 506 from wearing due to excessive force.

[0028] The propeller blade 1 adopts a gradual twist angle design, with the twist angle gradually decreasing from the center to the tip of the impeller 2. Combined with the leading edge arc transition and the trailing edge reduction design, it can optimize the path of airflow over the blade surface and reduce airflow separation. At the same time, the polytetrafluoroethylene modified noise reduction coating on the surface of the propeller blade 1 can reduce the friction coefficient between the airflow and the blade, reduce eddy noise, and achieve the dual effect of high-efficiency propulsion and low-noise operation.

[0029] When disassembling the propeller, rotate it in the opposite direction to remove the cover 507, press the pressing block 503 to retract the ball 506 into the receiving cavity, and then pull the propeller wheel 2 upward along the insertion rod 501 to complete the quick disassembly.

Claims

1. A high-efficiency, low-noise propeller for unmanned aerial vehicles, comprising a propeller blade (1) and a rotor wheel (2), characterized in that: One end of the spiral blade (1) is fixedly connected to the side wall of the propeller wheel (2). The spiral blade (1) is evenly distributed around the propeller wheel (2), and the number of the spiral blade (1) is set to five. The center of the propeller wheel (2) is provided with an installation hole (6), and two positioning holes (7) are provided inside the propeller wheel (2).

2. The high-efficiency, low-noise propeller for unmanned aerial vehicles according to claim 1, characterized in that: The helical blade (1) adopts a gradually decreasing twist angle design, with the twist angle gradually decreasing along the direction from the center of the propeller (2) to the tip of the helical blade (1).

3. The high-efficiency, low-noise propeller for unmanned aerial vehicles according to claim 1, characterized in that: The leading edge curve of the spiral blade (1) adopts a circular arc transition design, and the trailing edge curve adopts a reduced design. The surface of the spiral blade (1) is provided with a noise reduction coating. The noise reduction coating is a polytetrafluoroethylene modified coating, which is used to reduce the vortex noise generated by the interaction between the spiral blade (1) and the airflow when it rotates.

4. A high-efficiency, low-noise propeller mounting assembly for unmanned aerial vehicles (UAVs), as described in any one of claims 1-3, characterized in that: The high-efficiency, low-noise propeller mounting assembly for UAVs includes a motor mount (3), which is located at the bottom of the propeller wheel (2). A rotating seat (4) is fixedly connected inside the motor mount (3), and a mounting structure (5) is provided above the rotating seat (4). The mounting structure (5) includes a plug rod (501) and two positioning rods (502). One end of the plug rod (501) and the positioning rods (502) are fixedly connected to the upper surface of the rotating seat (4). The side wall of the plug rod (501) is slidably connected to the inside of the mounting hole (6). The side walls of the two positioning rods (502) are slidably connected to the inside of the positioning hole (7). A pressing block (503) is slidably connected inside the plug rod (501). A pusher is fixedly connected to the bottom of the pressing block (503). The push block (504) has a spring (505) inside the insert rod (501). One end of the spring (505) is fixedly connected to the inside of the insert rod (501), and the other end of the spring (505) is fixedly connected to the bottom of the push block (504). The insert rod (501) has multiple balls (506) inside. The side wall of the insert rod (501) has a receiving cavity that matches the balls (506). The side wall of the push block (504) has a limiting groove that matches the balls (506).

5. The high-efficiency, low-noise propeller mounting assembly for unmanned aerial vehicles according to claim 4, characterized in that: The mounting hole (6) has a groove on its inner wall. The groove is annular and matches the shape of the ball (506). One side of the ball (506) contacts the side wall of the push block (504), and the other side of the ball (506) can extend out of the outer wall of the insert rod (501) and engage with the groove.

6. The high-efficiency, low-noise propeller mounting assembly for unmanned aerial vehicles according to claim 5, characterized in that: The receiving cavity corresponds to the ball (506), and the receiving cavity is evenly distributed along the circumference of the insert (501), with a quantity of four. The ball (506) is made of stainless steel, and the outer diameter of the ball (506) is adapted to the aperture of the opening of the receiving cavity.

7. The high-efficiency, low-noise propeller mounting assembly for unmanned aerial vehicles according to claim 4, characterized in that: The mounting structure (5) also includes a cover (507), which is semi-circular and detachably connected to the top of the insert rod (501) by a thread, for further locking the paddle wheel (2).

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