Sand prevention device for power system of unmanned aerial vehicle

Abstract

The invention relates to the field of unmanned aerial vehicle protection, and discloses an unmanned aerial vehicle power system sand prevention device which comprises an unmanned aerial vehicle motor, and the output end of the unmanned aerial vehicle motor is in transmission connection with a motor transmission shaft; the unmanned aerial vehicle two-blade propeller is mounted at the front end of the motor transmission shaft; the sand-proof cover is fixedly connected to one side of the unmanned aerial vehicle motor, a motor transmission shaft is located in the sand-proof cover, and a plurality of flow guide holes are formed in the lower portion of the sand-proof cover; the rotational flow air inlet channel is arranged in the sand-proof cover and is close to an air inlet position on one side of the two-blade paddle of the unmanned aerial vehicle, the rotational flow air inlet channel adopts a tapered structure so as to reduce the flow resistance and improve the suction speed, a swirler mounted on one side of the sand-proof cover is arranged on one side of the rotational flow air inlet channel, the swirler is composed of a plurality of rotational flow guide blades, and the rotational flow guide blades are arranged in the rotational flow air inlet channel. All-path sand-proof and dust-proof control in the aerodynamic sense is achieved, the risk that a motor and a bearing are eroded by foreign matter is eliminated, the device can operate continuously and stably, the winding temperature rise and thrust attenuation phenomena are effectively prevented, and the reliability and the task persistence rate of the unmanned aerial vehicle are improved.

Description

Technical Field

[0001] This invention relates to the field of drone protection, and more particularly to a sand-proof device for a drone power system. Background Technology

[0002] In the current intelligent operation and maintenance system of large-scale new energy bases, drones have become important equipment for inspecting photovoltaic arrays, wind turbines, and transmission lines. However, in the complex environment of these areas, characterized by high dust concentrations, strong winds, and large temperature differences between day and night, the reliability of drone power systems faces severe challenges. During prolonged low-altitude cruises, a large amount of dust particles from the outside air are drawn into the motor nacelle and propeller area, leading to accelerated wear on the motor bearing surface, a continuous increase in coil winding temperature, a significant decrease in heat dissipation performance, and a gradual decline in thrust output efficiency. This results in problems such as unstable flight attitude, increased energy consumption, and even power failure.

[0003] Existing protection methods typically employ single-layer filters or simple sand shield structures. While these devices can block some sand and dust in a short period, they have significant drawbacks: First, the filter pore size and airflow channel design lack dynamic balance, leading to increased intake resistance and reduced heat dissipation efficiency. Second, the filter element is prone to rapid clogging in high dust concentration environments, requiring manual disassembly and cleaning, which cannot meet the needs of long-term autonomous cruise and unattended operation. Third, some structures are prone to airflow turbulence under sand and dust impact or dust accumulation, causing localized overheating zones inside the motor, further exacerbating performance degradation, and thus affecting the overall performance of the drone. Summary of the Invention

[0004] To address the technical problem of uneven protection and cooling, this invention provides a sand-proof device for a drone power system.

[0005] This invention is achieved using the following technical solution: a sand-proof device for a drone power system, comprising:

[0006] The drone motor, with its output end connected to a motor drive shaft, is mounted at the tail of the sand shield, providing mechanical power to the system. The motor's housing is made of high thermal conductivity aluminum alloy and features longitudinal heat dissipation fins to improve heat exchange efficiency. The motor's output power range is compatible with multi-rotor platforms (typically 600-1500W), driving the propellers and also working in conjunction with a positive pressure air duct to generate internal cooling circulation.

[0007] The drone's two-bladed propeller, mounted at the front end of the motor drive shaft, provides the main thrust for the drone. Made of carbon fiber composite material, the propeller boasts high strength and lightweight characteristics. Its rotation not only generates lift and thrust but also induces a mainstream airflow, driving air circulation within the sand shield.

[0008] The sand shield is fixedly connected to one side of the drone's motor, with the motor's drive shaft located inside the sand shield. Several airflow guide holes are located at the bottom of the sand shield. The sand shield serves as the outer protective shell of the entire system, made of lightweight carbon fiber composite material, and features impact resistance, sand erosion resistance, and high airtightness. The airflow guide holes utilize the internal and external pressure difference to create localized negative pressure zones, thereby inducing dust to be automatically expelled from the cabin with the airflow. The sand shield also has aerodynamic rectification capabilities, reducing external wind resistance and noise.

[0009] The swirling air intake channel is located inside the sand shield and near the air intake position on the side of the UAV's two-bladed propeller. The swirling air intake channel adopts a tapered structure to reduce flow resistance and increase the intake speed. A swirler is installed on one side of the swirling air intake channel and is composed of multiple swirling guide vanes. The swirling guide vanes give the incoming air a significant tangential velocity component, forming a strong rotating flow field. It can perform preliminary separation of the outside air without losing the intake volume, causing large dust particles to be thrown towards the wall of the air intake channel under the action of centrifugal force.

[0010] The coarse-pore dust filter is fixed in the cyclone intake channel, away from the outlet of the UAV's two-bladed propeller. This filter ensures adequate ventilation while achieving primary filtration.

[0011] The first outer air outlet is located on one side of the sand cover. The first outer air outlet adopts an arc-shaped guide hole array shape. The first outer air outlet is used to discharge excess airflow and maintain the balance of outer air pressure. The arc-shaped guide hole array can use the inertia of airflow to carry out fine dust particles attached to the inner wall of the sand cover.

[0012] The second outer air outlet is located on the side rear or lower edge of the sand cover. It guides the airflow after filtration and heat dissipation in the chamber to be discharged smoothly, and forms an outer airflow guide and negative pressure induction effect. In this way, while maintaining the air pressure balance of the sand cover, it realizes the auxiliary functions of automatic dust removal and heat dissipation of the outer shell.

[0013] The positive pressure air duct is located on one side surrounding the motor and inside the sand cover, forming a closed annular cooling channel. A centrifugal dust filter chamber is formed between the sand cover and the positive pressure air duct. An inner air outlet connected to the centrifugal dust filter chamber is opened on one side of the positive pressure air duct. The air purified by the centrifugal dust filter chamber enters the positive pressure air duct through the inner air outlet and flows along the outer shell of the UAV motor to form a uniform positive pressure layer. The airflow pressure is 0.3-0.6 kPa higher than that of the negative pressure air duct. This positive pressure airflow can not only remove the heat of the motor, but also effectively prevent external sand and dust from flowing back into the cabin through the gaps, thus having the dual functions of dust prevention and heat dissipation.

[0014] The negative pressure air duct is located at the bottom of the sand cover and is connected to the air guide hole of the sand cover. The negative pressure air duct uses the negative pressure of the fluid formed during the exhaust stage to suck away the dust trapped at the bottom, so as to realize the self-cleaning function of the system.

[0015] The fine-pore dust filter screen, installed at the outlet end of the centrifugal dust filter chamber, can trap fine dust.

[0016] An automatic dust removal channel is located on the side of the sand cover near the drone motor and is connected to the centrifugal dust filter chamber. One end of the automatic dust removal channel extends to the outside of the sand cover. The automatic dust removal channel is used to directionally discharge the separated sand and dust particles to remove dust.

[0017] As a further improvement to the above scheme, the swirling guide vanes are distributed circumferentially at a 35° angle to create a rotating flow field for the gas. There are 8 swirling guide vanes. The 35° angled swirling guide vanes allow the incoming air to obtain a larger tangential velocity component, forming a strong rotating flow field. The angle and shape of the swirling guide vanes determine the swirling intensity and separation efficiency. The swirling guide vanes are integrally formed from wear-resistant aluminum alloy, with a smooth transition at the leading edge and a guiding bend at the trailing edge, which can effectively prevent airflow separation. Through simulation optimization, the guide vane angle of 35° and the number of guide vanes of 8 were determined to achieve a stable swirling field and reduce energy loss at an inlet speed of 20 m / s.

[0018] As a further improvement to the above solution, the coarse-pore dust filter uses a metal wire woven mesh or composite dustproof fiber material with a pore size of 80-120μm, which can achieve primary filtration while ensuring ventilation and extending the overall service life.

[0019] As a further improvement to the above solution, the automatic dust removal channel is equipped with a flexible one-way valve structure. When the pressure difference inside the chamber reaches the set value (0.5-0.6 kPa), the valve opens instantly, relying on the internal positive pressure airflow pulse to spray out the accumulated dust. The valve body is made of wear-resistant silicone rubber material, ensuring reliable sealing and a long service life.

[0020] As a further improvement to the above scheme, the inner wall of the centrifugal dust filter chamber is treated with a Teflon anti-adhesion coating, and the radius of the centrifugal dust filter chamber is 20-50mm and the length is 60-100mm.

[0021] As a further improvement to the above solution, the fine-pore dust filter is made of polymer nanofiber composite material with a pore size of 10-40μm. The fine-pore dust filter is the last-stage barrier for purifying airflow and can trap fine dust particles.

[0022] As a further improvement to the above solution, the back of the fine-pore dust filter is equipped with an electromagnetic vibrator assembly with a periodic vibration frequency of 150-300Hz. The electromagnetic vibrator assembly is used to shake off attached particles and maintain long-term low-resistance ventilation performance.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] This invention employs a four-level protection mechanism of "cyclone introduction - centrifugal separation - filter self-cleaning - positive pressure flow guidance," achieving full-path sand and dust prevention control in an aerodynamic sense. It eliminates the risk of foreign objects corroding the motor and bearings from the source. In high-wind and sandy environments, the device can operate continuously and stably, effectively preventing winding temperature rise and thrust attenuation, thereby significantly improving the reliability and mission continuity of the UAV.

[0025] This invention constructs an active dust removal mechanism of "pneumatic pressure differential triggering + vibration-assisted dust removal". The entire dust removal process does not require manual intervention and can be completed periodically in an unattended state. The air permeability remains stable, which greatly reduces the maintenance frequency and labor costs. It is particularly suitable for large-scale new energy bases, remote inspection and unmanned operation and maintenance scenarios in high-altitude areas.

[0026] Each sub-module of this invention (cyclone air intake assembly, centrifugal cavity, dust filter unit, positive pressure air duct and sand cover) adopts a modular interface design, which can be independently disassembled and maintained or quickly replaced. It is compatible with various platforms such as quadcopter, hexcopter and vertical take-off and landing compound wing UAV, and can realize large-scale industrial production. Attached Figure Description

[0027] Figure 1 This is an overall structural diagram of the present invention;

[0028] Figure 2 This is a partial front sectional view of the present invention;

[0029] Figure 3 This is a partial front view structural diagram of the present invention;

[0030] Figure 4 This is a partial rear view structural diagram of the present invention.

[0031] Explanation of key symbols:

[0032] 1. Two-bladed drone propeller; 2. Swirl air intake channel; 3. Coarse-pore dust filter; 4. Motor drive shaft; 5. Inner air outlet; 6. Swirl guide vanes; 7. Outer air outlet one; 8. Sand cover; 9. Automatic dust removal channel; 10. Outer air outlet two; 11. Positive pressure air duct; 12. Centrifugal dust filter chamber; 13. Drone motor; 14. Negative pressure air duct; 15. Fine-pore dust filter. Detailed Implementation

[0033] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0034] Example: Please refer to Figure 1 - Figure 4 The implementation principle of this application embodiment is as follows:

[0035] When the power is turned on, the drone motor 13 drives the drone's two-bladed propeller 1 to rotate through the motor drive shaft 4, providing lift and causing external air to enter the device through the swirling air intake channel 2. The coarse-pore dust filter 3 blocks large-diameter sand and dust. After the gas enters the sand cover 8, it forms a stable high-speed vortex flow field under the guidance of the swirling guide vanes 6, achieving primary separation of large sand and dust particles. The airflow then enters the centrifugal dust filter chamber 12, where secondary separation takes place in the strong swirling flow field. Large dust particles are thrown against the chamber wall by centrifugal force and settle into the bottom dust collection tank, and are discharged through the automatic dust discharge channel 9.

[0036] After being purified, the air undergoes final filtration through the fine-mesh dust filter 15 before entering the positive pressure air duct 11 surrounding the outer wall of the UAV motor 13. In this area, the airflow pressure is approximately 0.4-0.6 kPa higher than the external environment, forming a stable internal positive pressure air layer. This ensures that the cooling airflow continuously flows over the surface of the UAV motor 13 to dissipate heat, while also effectively preventing external dust from seeping back into the cabin through gaps.

[0037] Meanwhile, the negative pressure duct 14 at the bottom of the sand shield 8 and the guide holes of the sand shield 8 form a complementary air path. When the airflow in the positive pressure duct 11 is discharged, its velocity increases, causing a pressure drop zone to form on the outer layer of the cabin. Under the influence of fluid, the negative pressure duct 14 at the bottom forms a low pressure relative to the external environment. Since the pressure in the positive pressure duct is higher than that in the negative pressure duct, the airflow inside the cabin forms a directional flow along the pressure difference direction, forming a stable pressure gradient. This allows sand and dust particles to be blown out of the cabin from bottom to top and from the inside to the outside by the high-speed airflow. This process can achieve automatic dust removal without the need for external power, keeping the cabin clean and the airflow unobstructed.

[0038] Furthermore, the combined effect of the positive and negative pressure air ducts creates an "upward exhaust and downward suction" airflow circulation. The airflow discharged from the positive pressure air duct 11 is directed out through the outer air outlet 7 of the sand shield 8, carrying away heat from the cabin; while the suction zone formed by the bottom negative pressure air duct 14 induces residual fine dust to move along the automatic dust removal channel 9 and be discharged with the airflow, thereby achieving continuous self-cleaning. This dust flow transport mechanism guided by air pressure difference ensures the long-term stable operation of the sand shield device in high wind and sand, high dust environments.

[0039] Specifically, when the inlet velocity is 20 m / s, the cyclone guide vane angle is 35°, the centrifugal dust filter chamber radius is 35 mm, and the length is 80 mm, the device can achieve a large particle separation efficiency of over 95% and a fine particle filtration efficiency of over 85% under a pressure difference of 0.4-0.6 kPa, while keeping the airflow temperature rise below 5°C. This achieves a triple synergistic function of sand and dust prevention and heat dissipation, ensuring the safe and stable operation of the drone for extended periods in environments with strong winds, high dust levels, and extreme temperature differences.

[0040] In summary, the airflow and protection process of this device can be summarized into five stages: "cyclone rectification - centrifugal separation - multi-layer filtration - positive pressure guidance - automatic dust removal".

[0041] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A sand-proof device for a drone power system, characterized in that, include: The drone motor (13) has a motor drive shaft (4) connected to its output end. The UAV has a two-bladed propeller (1), which is mounted at the front end of the motor drive shaft (4); The sand cover (8) is fixedly connected to one side of the UAV motor (13), and the motor drive shaft (4) is located inside the sand cover (8). Several guide holes are provided below the sand cover (8). The swirling air intake channel (2) is located inside the sand shield (8) and near the air intake position of the UAV two-bladed propeller (1). The swirling air intake channel (2) adopts a tapered structure to reduce flow resistance and increase suction speed. A swirler is installed on one side of the swirling air intake channel (2) and is composed of multiple swirling guide vanes (6). A positive pressure air duct (11) is located on one side of the motor (13) and inside the sand cover (8) to form a closed annular cooling channel. A centrifugal dust filter chamber (12) is formed between the sand cover (8) and the positive pressure air duct (11). An inner air outlet (5) connected to the centrifugal dust filter chamber (12) is opened on one side of the positive pressure air duct (11). Negative pressure air duct (14) is arranged at the bottom of the sand cover (8) and connected to the guide hole of the sand cover (8); The sand shield (8) is also connected to a flow guiding and filtering mechanism on one side.

2. The sand-proof device for a drone power system as described in claim 1, characterized in that, The flow guiding and filtering mechanism includes: The outer air outlet 1 (7) is located on one side of the sand cover (8), and the outer air outlet 1 (7) adopts an arc-shaped guide hole array shape; The second outer air outlet (10) is located at the rear side or lower edge of the sand shield (8). It guides the airflow after filtration and heat dissipation in the chamber to be discharged smoothly, and forms an outer airflow guiding and negative pressure induction effect. Fine-mesh dust filter (15) is installed at the outlet end of the centrifugal dust filter chamber (12); An automatic dust removal channel (9) is set on the side of the sand cover (8) near the drone motor (13), and the automatic dust removal channel (9) is connected to the centrifugal dust filter chamber (12). One end of the automatic dust removal channel (9) extends to the outside of the sand cover (8). A coarse-pore dust filter (3) is fixed at the outlet position of the swirl air intake channel (2) away from the two-bladed propeller (1) of the UAV.

3. The sand-proof device for a drone power system as described in claim 2, characterized in that, The swirling guide vanes (6) are distributed around the circumference at an angle of 35° to create a rotating flow field for the gas. There are 8 swirling guide vanes (6).

4. The sand-proof device for a drone power system as described in claim 2, characterized in that, The coarse-pore dust filter (3) is made of woven metal wire mesh or composite dustproof fiber material, with a pore size of 80-120μm.

5. A sand-proof device for a drone power system as described in claim 2, characterized in that, The automatic dust removal channel (9) is equipped with a flexible one-way valve structure, and the valve body is made of wear-resistant silicone rubber material.

6. A sand-proof device for a drone power system as described in claim 2, characterized in that, The inner wall of the centrifugal dust filter chamber (12) is treated with a Teflon anti-adhesion coating. The centrifugal dust filter chamber (12) has a radius of 20-50 mm and a length of 60-100 mm.

7. A sand-proof device for a drone power system as described in claim 2, characterized in that, The fine-pore dust filter (15) is made of polymer nanofiber composite material with a pore size of 10-40 μm.

8. A sand-proof device for a drone power system as described in claim 2, characterized in that, The back of the fine-pore dust filter (15) is equipped with an electromagnetic oscillator assembly with a periodic vibration frequency of 150-300Hz.

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