Multi-rotor unmanned aerial vehicle

Abstract

The multi-rotor unmanned aerial vehicle comprises an unmanned aerial vehicle body and rotors, the rotors are fixedly connected with the unmanned aerial vehicle body through supporting arms, the rotors comprise blades, the blades are located above the supporting arms, an electronic equipment chamber is arranged in the unmanned aerial vehicle body, the supporting arms are hollow pipes, and heat pipes connected with the electronic equipment chamber are arranged in the supporting arms. An air inlet facing the blade and an air outlet opposite to the blade are formed in the support arm, so that airflow generated by the blade flows through the heat pipe. The unmanned aerial vehicle has the advantage that the problem of poor heat dissipation of electrical elements in an existing unmanned aerial vehicle body is solved. Heat dissipation holes do not need to be formed in the electronic equipment chamber, the air tightness of the electronic equipment chamber is guaranteed, and the electronic equipment chamber has certain waterproof and dustproof capacity. The supporting arms are arranged in the hollow pipes, the heat pipes are arranged in the supporting arms in a penetrating mode, flowing air is promoted to be generated in the supporting arms through downward pressing wind force generated when the rotor wings rotate, the heat pipes are cooled, in this way, active heat dissipation is provided for the heat pipes, the supporting arms can be used for protecting the heat pipes, and the heat pipes are prevented from being exposed and damaged.

Description

Technical Field

[0001] The present invention relates to the field of unmanned aerial vehicles (UAVs), and in particular to a multi-rotor UAV. Background Art

[0002] Drones are now widely used. A typical drone consists of a main body and rotors, which are fixed to the main body via arms and driven by motors. The drone's control system is typically located within the main body. In some specialized environments, high heat dissipation requirements are placed on the drone's electrical equipment, while also requiring certain waterproof and dustproof properties. Therefore, it's not possible to create numerous cooling holes in the drone's main body, resulting in poor heat dissipation from the electrical components within the drone. Summary of the Invention

[0003] The purpose of the present invention is to provide a multi-rotor drone that can effectively solve the problem of poor heat dissipation of electrical components in the main body of existing drones.

[0004] In order to solve the above technical problems, the present invention is achieved through the following technical solutions:

[0005] A multi-rotor drone comprises a drone body and rotors, wherein the rotors are fixedly connected to the drone body via a support arm, the rotors include blades, and the blades are located above the support arm. An electronic equipment compartment is provided within the drone body, and the support arm is a hollow tube. A heat pipe connected to the electronic equipment compartment is provided within the support arm. The support arm is provided with an air inlet facing the blades and an air outlet facing away from the blades, so that the airflow generated by the blades flows through the heat pipe.

[0006] In the above multi-rotor drone, the projections of the air inlet and the air outlet on the horizontal plane do not overlap.

[0007] In the above-mentioned multi-rotor drone, the air inlet is located at one end of the support arm close to the rotor, and the air outlet is located at one end of the support arm close to the drone body.

[0008] In the above-mentioned multi-rotor drone, a heat exchanger is provided in the electronic equipment room, and the heat exchanger is connected to the heat pipe to exchange heat in the drone body to the heat pipe.

[0009] In the above multi-rotor drone, an air guide groove is provided at the air outlet, and the air guide groove includes an inlet and an outlet, and the cross-sectional area of ​​the inlet is greater than the cross-sectional area of ​​the outlet.

[0010] In the above-mentioned multi-rotor UAV, the air guide groove is trumpet-shaped; or, the cross section of the air guide groove is V-shaped.

[0011] In the above multi-rotor drone, a Laval nozzle is provided at the air outlet.

[0012] In the above multi-rotor UAV, a radiator is further provided in the support arm, and the heat pipe is connected to the radiator.

[0013] Compared with the prior art, the advantages of the present invention are:

[0014] By connecting the electronic equipment compartment within the drone's main body with the heat pipe within the hollow support arm, the heat generated by the electrical components within the electronic equipment compartment is quickly conducted to the support arm area using the heat pipe's efficient thermal conductivity, solving the problem of low heat dissipation efficiency in traditional closed cavities. The support arm is provided with an air inlet facing the blades and an air outlet facing away from the blades. This allows the downward pressure airflow generated by the rotation of the rotor to flow directly over the surface of the heat pipe, creating a "passive air cooling" effect. This allows for continuous heat dissipation without the need for additional power consumption, thereby improving the energy efficiency of the cooling system. By utilizing the airflow generated by the normal operation of the rotor as the driving force for heat dissipation, no additional fans or power units are required. This achieves heat dissipation without increasing the drone's energy consumption, maintaining flight endurance. The layout of the air inlet and outlet allows the airflow direction to naturally couple with the rotor airflow, forming a smooth heat dissipation channel, reducing airflow resistance, and avoiding negative effects on the drone's flight stability.

[0015] Integrating the heat pipes within the hollow arms eliminates the need for heat dissipation holes on the drone's surface, thus preventing damage to the aircraft's structural integrity. The arms also utilize the physical space within the arms to create a heat dissipation path, improving overall structural compactness. The arms, acting as the heat pipe's physical enclosure, effectively protect it from mechanical damage, such as collisions and scratches. This makes them particularly suitable for complex flight environments, enhancing the reliability of the cooling system.

[0016] By eliminating the need for heat dissipation vents in the electronics compartment, the system ensures high airtightness in the area, effectively blocking the intrusion of moisture, dust, and foreign matter. This meets the needs of drones operating in harsh environments such as humid, dusty, and rainy environments (e.g., agricultural plant protection and industrial inspections), improving the equipment's environmental adaptability. The physical structural design achieves heat dissipation, avoiding the potential sealing risks associated with traditional heat dissipation vents, meeting the protection level requirements of drones and extending the service life of electronic equipment.

[0017] Furthermore, the horizontal projections of the air inlet and outlet do not overlap. By staggering the inlet and outlet, the airflow is forced to form a non-linear flow path within the arm, increasing the contact time and area between the airflow and the heat pipe. This staggered layout forces the airflow to cover the entire length of the heat pipe, eliminating heat dissipation blind spots. This is particularly suitable for structures with long arms or multiple heat pipe sections, ensuring uniform heat dissipation.

[0018] Furthermore, the air inlet is located at one end of the support arm close to the rotor, and the air outlet is located at one end of the support arm close to the drone body. The air inlet is arranged close to the rotor to directly capture the high-speed downward pressure airflow generated when the rotor rotates (the wind speed is highest and the kinetic energy is strongest near the rotor end), ensuring that the airflow entering the support arm is sufficient and the temperature is low, providing an efficient cooling source for the heat pipe. The airflow pressure at the rotor end is higher than that at the fuselage end, and this pressure difference is used to form a one-way flow of "strong air inlet-weak air outlet", which can drive the airflow to flow continuously through the heat pipe without additional power, thereby reducing system energy consumption.

[0019] Furthermore, a heat exchanger is provided in the electronic equipment room, and the heat exchanger is connected to the heat pipe for exchanging heat in the main body of the drone to the heat pipe. The heat exchanger (such as fin-type or plate-type structure) can significantly increase the contact area with the electrical components in the electronic equipment room. Compared with direct contact with the heat pipe, it can absorb heat more quickly and comprehensively (for example, covering multiple heat-generating chips or modules), solving the problem of limited heat absorption efficiency of a single heat pipe. Through the conductive medium of the heat exchanger (such as a metal substrate), the dispersed heat can be concentrated to the heat pipe, forming an efficient heat conduction path of "multi-point collection-single-point export", which is particularly suitable for electronic equipment rooms with high power density.

[0020] Furthermore, an air guide groove is provided at the air outlet, and the air guide groove includes an inlet and an outlet, and the cross-sectional area of ​​the inlet is greater than the cross-sectional area of ​​the outlet. By utilizing the contraction structure of the air guide groove with "large inlet and small outlet", the flow velocity increases due to the reduction in cross-sectional area when the air flow passes through (following the principle of fluid continuity), forming an acceleration effect similar to that of a Venturi tube. This can offset the power loss caused by the negative pressure area (Karman vortex street effect) generated under the rotor due to the existence of the air outlet, and maintain the overall lift balance of the drone. When the traditional air outlet directly discharges the airflow, part of the kinetic energy will be dissipated due to turbulence in the negative pressure area; the air guide groove converts the originally lost kinetic energy into propulsion or lift compensation by accelerating the airflow jet, especially when the multi-rotor drone is hovering or flying at low speed, which can improve the flight time or payload capacity.

[0021] Furthermore, the air guide groove is trumpet-shaped; or, the cross-section of the air guide groove is V-shaped. Air guide grooves of different shapes can be selected according to the size of the UAV and the thickness of the arm, and they can all play a good air guiding effect. The trumpet-shaped structure makes a smooth curve transition (large inlet and small outlet) so that the airflow speed increases evenly during the flow process, reducing turbulence and energy loss caused by sudden changes in cross-section. It is suitable for scenes with large arm diameters or where gentle acceleration is required. The trumpet-shaped outlet can guide the airflow to diffuse outward, avoiding high-speed airflow from directly impacting the fuselage or adjacent arms, reducing aerodynamic interference, and is especially suitable for UAVs with densely arranged multiple arms. The V-shaped structure forms an acute-angle contraction (such as an isosceles V-shape or a trapezoid) through the inclined surfaces on both sides, realizing rapid airflow acceleration in a limited space. It is suitable for scenes with small arm diameters or sensitive to installation space, and the two sides of the V-shape can force the airflow to be discharged in a specific direction (such as radial or tangential direction of the arm), further reducing turbulence and improving the controllability of the airflow direction.

[0022] Furthermore, a Laval nozzle is provided at the air outlet. Another air outlet structure that compensates for the power lost due to the introduction of dynamic airflow. The Laval nozzle uses a "contraction-expansion" cross-section design (first contraction and then expansion) to enable the airflow to reach the speed of sound at the throat and achieve supersonic jetting at the outlet. This feature can significantly increase the airflow discharge speed and effectively offset the power loss in the negative pressure area under the rotor caused by the air outlet. Especially in high-speed flight or heavy-load scenarios of drones, the reverse thrust effect of the nozzle can compensate for part of the lift or propulsion force, thereby improving flight stability. Compared with traditional air outlets or simple contraction-type air guide slots, the Laval nozzle can convert the kinetic energy loss of the airflow into directional thrust, reducing the overall power attenuation caused by heat dissipation. For example, when a multi-rotor drone is hovering, the airflow accelerated by the nozzle can form "aerodynamic support", reducing the power consumption of the rotor and extending the flight time. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a cross-sectional view of a multi-rotor UAV of the present invention;

[0024] Figure 2 for Figure 1 The first structure of the AA section view;

[0025] Figure 3 for Figure 1 The second structure of the AA section view;

[0026] Figure 4 for Figure 1 The third structure of the AA section view.

[0027] The accompanying drawings are:

[0028] UAV body 1, rotor 2, support arm 3, electronic equipment room 4, heat pipe 5, blade 6, air inlet 7, air outlet 8, heat exchanger 9, radiator 10, air guide slot 11, Laval nozzle 12. DETAILED DESCRIPTION

[0029] A multi-rotor drone comprises a drone body 1 and rotors 2, the rotors 2 being fixedly connected to the drone body 1 via a support arm 3. The rotors 2 include blades 6, which are located above the support arm 3. An electronic equipment compartment 4 is provided in the drone body 1. The support arm 3 is a hollow tube. A heat pipe 5 connected to the electronic equipment compartment 4 is provided in the support arm 3. An air inlet 7 facing the blades 6 and an air outlet 8 facing away from the blades 6 are provided on the support arm 3, so that the airflow generated by the blades 6 flows through the heat pipe 5.

[0030] Utilizing heat pipes 5 to conduct heat away from the electronic equipment compartment 4 solves the current problem of poor heat dissipation of electrical components within the drone body 1. Heat conduction from the electronic equipment compartment 4 via the heat pipes 5 eliminates the need for heat dissipation holes in the compartment 4, ensuring the compartment's airtightness and imparting a degree of waterproof and dustproof properties. The arm 3 is disposed within a hollow tube, and the heat pipe 5 is inserted within the arm 3. The downward pressure generated by the rotation of the rotor 2 creates air flow within the arm 3, cooling the heat pipe 5. This provides active heat dissipation for the heat pipe 5 and also protects the heat pipe 5 from damage caused by exposure to the elements.

[0031] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0032] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0033] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0034] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0035] See Figure 1 This is an embodiment of a multi-rotor drone of the present invention. The multi-rotor drone includes a drone body 1 and rotors 2. The rotors 2 are fixedly connected to the drone body 1 via arms 3. Generally, one end of the arms 3 is fixed to the drone body 1, and the arms 3 are radially distributed. Depending on the size of the drone body 1, the number of arms 3 is generally four, six, or eight. A motor is fixed to the other end of the arms 3 to drive the rotors 2 to rotate. In this embodiment, the rotors 2 are located above the arms 3. The rotation of the rotors 2 generates downward wind, which propels the drone upward.

[0036] An electronic equipment compartment 4 is provided within the drone body 1. Several electrical components are located within the electronic equipment compartment 4 to enable communication with ground personnel and control the drone's flight posture. The electronic equipment compartment 4 is generally closed to prevent moisture from the outside from entering the electronic equipment compartment 4 during flight. The arm 3 in this embodiment is a hollow tube. A heat pipe 5 is provided within the arm 3. One end of the heat pipe 5 extends through the side wall of the electronic equipment compartment 4 and into the electronic equipment compartment 4. The arm 3 is provided with an air inlet 7 facing the blades 6 and an air outlet 8 facing away from the blades 6. The heat pipe 5 absorbs heat from the electronic equipment compartment 4 and conducts it to the heat pipe 5 within the arm 3. The downward pressure generated by the rotor 2 during rotation enters the hollow tube through the air inlet 7, carrying the heat from the heat pipe 5 away from the air outlet 8, thereby cooling the heat pipe 5. The heat in the closed electronic equipment room 4 can be conducted out through the heat pipe 5, and the wind generated by the rotor 2 can be used to dissipate heat, thereby achieving the purpose of cooling the electronic equipment room 4. The hollow tube in the support arm 3 can also stabilize the airflow, allowing the airflow generated by the rotor 2 to flow through the heat pipe 5 in an orderly manner, ensuring effective heat exchange efficiency. On the other hand, the support arm 3 can also provide protection for the heat pipe 5 to prevent the heat pipe 5 from being damaged due to accidental collision of the drone.

[0037] On the basis of the above embodiment, the air inlet 7 is located at one end of the support arm 3 close to the rotor 2, and the air outlet 8 is located at one end of the support arm 3 close to the drone body 1. This can extend the area of ​​contact between the airflow entering the support arm 3 and the heat pipe 5 as much as possible, improve the heat exchange efficiency, and more efficiently take away the heat of the heat pipe 5.

[0038] In addition, a heat exchanger 9 can be installed in the electronic equipment compartment 4. The heat exchanger 9 is connected to the heat pipe 5. The heat exchanger 9 expands the area of ​​heat absorption in the electronic equipment compartment 4. The absorbed heat is then exchanged with the heat pipe 5, further improving the efficiency of heat exchange between the heat in the electronic equipment compartment 4 and the heat pipe 5. A radiator 10 can also be installed on the heat pipe 5 in the support arm 3 to expand the contact area between the heat pipe 5 and the airflow and improve the heat exchange efficiency. The radiator 10 can be fins that are directly welded to the heat pipe 5 to improve the heat exchange efficiency between the radiator 10 and the heat pipe 5.

[0039] Because there is an air outlet 8 below the rotor 2, when the airflow generated by the rotor 2 passes through the air outlet 8, a negative pressure area will be generated. The negative pressure area will cause partial power loss. In order to compensate for the lost power, the air passing through the heat pipe 5 can be discharged through the air outlet 8 with a convergent effect, reducing the pressure difference in the negative pressure area, thereby compensating for the power loss of the power airflow. Specifically, the following structural forms can be adopted:

[0040] One method is to set an air guide groove 11 at the air outlet 8. The air guide groove 11 includes an inlet and an outlet. The cross-sectional area of ​​the inlet is greater than the cross-street area of ​​the outlet, thereby accelerating the airflow velocity at the outlet. By utilizing the contraction structure of the air guide groove with "large inlet and small outlet", the airflow velocity increases due to the reduction in cross-sectional area when passing through (following the principle of fluid continuity), forming an acceleration effect similar to that of a Venturi tube. This can offset the power loss caused by the negative pressure area (Karman vortex street effect) generated under the rotor due to the existence of the air outlet, and maintain the overall lift balance of the drone. When the traditional air outlet directly discharges the airflow, part of the kinetic energy will be dissipated due to turbulence in the negative pressure area; the air guide groove converts the originally lost kinetic energy into propulsion or lift compensation by accelerating the airflow jet, especially when the multi-rotor drone is hovering or flying at low speed, which can improve the flight time or payload capacity. The structure of the air duct constrains the direction of airflow, directing it more concentratedly away from the rotors. This prevents the airflow from spreading outward and forming turbulence, reducing aerodynamic interference with the drone's fuselage or adjacent arms. The constricted outlet minimizes airflow separation, lowering the local drag coefficient at the outlet, allowing the heat dissipation within the arms to be discharged more smoothly, improving the cooling efficiency of the heat pipes. This achieves airflow dynamic compensation, optimized exhaust efficiency, and enhanced structural protection without increasing energy consumption. This is a key innovation in balancing heat dissipation and aerodynamic performance in multi-rotor drones, making it particularly suitable for complex scenarios requiring long, stable flight.

[0041] Specifically, Figure 2 As shown, the air guide groove 11 is long and has a V-shaped cross section, forming a structure that is larger at the top and smaller at the bottom. The V-shaped structure forms an acute-angle contraction (such as an isosceles V-shape or a trapezoid) through the inclined surfaces on both sides, which realizes rapid airflow acceleration in a limited space. It is suitable for scenarios with small arm diameters or sensitive installation space (such as small / micro drones). The two sides of the V-shape can force the airflow to be discharged in a specific direction (such as the radial or tangential direction of the arm), further reducing turbulence and improving the controllability of the airflow direction (for example, in conjunction with the aerodynamic shape design of the drone, guiding the airflow to assist in the stability of the fuselage). The V-shaped structure can be achieved through metal bending or 3D printing, with low processing difficulty, and is convenient for small-batch customization or rapid prototyping.

[0042] Or, as Figure 3 As shown, the air guide groove 11 is trumpet-shaped, with the larger end being the inlet and the smaller end being the outlet, which can also achieve the purpose of accelerating the ejection of airflow. The trumpet-shaped structure makes the airflow velocity increase uniformly during the flow process through a smooth curve transition (large inlet and small outlet), reducing turbulence and energy loss caused by sudden changes in cross-section. It is suitable for scenarios with large arm diameters or that require gentle acceleration (such as large drones). The trumpet-shaped outlet can guide the airflow to diffuse outward, avoiding high-speed airflow directly impacting the fuselage or adjacent arms, reducing aerodynamic interference, and is especially suitable for drones with densely arranged multiple arms (such as six-rotors and eight-rotors). The trumpet shape can be integrally formed through processes such as injection molding and stamping, with a smooth surface and no stress concentration points, making it suitable for large-scale mass production.

[0043] Another is as Figure 4 As shown, a Laval nozzle 12 is provided at the air outlet 8 to accelerate the ejected airflow. The Laval nozzle uses a "contraction-expansion" cross-sectional design (first contraction and then expansion) to enable the airflow to reach the speed of sound at the throat and achieve supersonic jetting at the outlet. This feature can significantly increase the airflow discharge speed and effectively offset the power loss in the negative pressure area under the rotor due to the air outlet. Especially in scenarios where the UAV is flying at high speed or with a large load, the reverse thrust effect of the nozzle can compensate for part of the lift or propulsion force, thereby improving flight stability. Compared with traditional air outlets or simple contraction-type air guide slots, the Laval nozzle can convert the kinetic energy loss of the airflow into directional thrust, reducing the overall power attenuation caused by heat dissipation. For example, when a multi-rotor UAV is hovering, the airflow accelerated by the nozzle can form an "aerodynamic support", reducing the power consumption of the rotor and extending the flight time. When the electronic equipment room is in a high-heat state (such as long-term full-load computing), the nozzle's strong acceleration capability can quickly increase the airflow update frequency in the support arm, enhance the cooling efficiency of the heat pipe, and prevent temperature exceeding the limit. It is suitable for scenarios with extremely high reliability requirements such as industrial testing and emergency rescue.

[0044] When the drone starts working, the heat generated in the electronic equipment room 4 is absorbed by the heat exchanger 9 and conducted to the heat pipe 5. The heat pipe 5 transfers the heat from one end of the electronic equipment room 4 to the part located inside the arm 3. The rotor 2 rotates and generates a downward airflow. Part of the airflow enters the arm 3 through the air inlet 7 on the arm 3. After the airflow flows through the heat pipe 5, the heat of the heat pipe 5 is taken away. When the airflow flows out from the air outlet 8, it is accelerated by the air guide groove 11 or the Laval nozzle 12, which offsets the negative pressure of the arm 3 at the air outlet 8, so that the compensation power of the ejected airflow is greater than the power sacrificed by the airflow of the rotor 2. Through the above technical solution, under the premise of ensuring that the electronic equipment room 4 is sealed, the heat pipe 5 provides heat dissipation for the electronic equipment room 4, ensuring that the electrical components in the electronic equipment room 4 can work normally.

[0045] The above description is only a specific embodiment of the present invention, but the technical features of the present invention are not limited thereto. Any changes or modifications made by any technician in this field within the scope of the present invention are included in the patent scope of the present invention.

Claims

1. A multi-rotor drone, comprising a drone body and rotors, wherein the rotors are fixedly connected to the drone body via a support arm, the rotors comprising blades, and the blades are located above the support arm, characterized in that: An electronic equipment room is provided in the drone body, the support arm is a hollow tube, a heat pipe connected to the electronic equipment room is provided in the support arm, and an air inlet facing the blade and an air outlet facing away from the blade are opened on the support arm, so that the airflow generated by the blade flows through the heat pipe.

2. A multi-rotor drone according to claim 1, characterized in that: The projections of the air inlet and the air outlet on the horizontal plane do not overlap.

3. A multi-rotor UAV according to claim 2, characterized in that: The air inlet is located on one end of the support arm close to the rotor, and the air outlet is located on one end of the support arm close to the drone body.

4. A multi-rotor UAV according to claim 1, characterized in that: A heat exchanger is provided in the electronic equipment room, and the heat exchanger is connected to the heat pipe for exchanging heat in the drone body to the heat pipe.

5. The multi-rotor UAV according to claim 1, characterized in that: A radiator is also provided in the support arm, and the heat pipe is connected to the radiator.

6. The multi-rotor UAV according to claim 1, characterized in that: An air guide groove is provided at the air outlet, and the air guide groove includes an inlet and an outlet, and the cross-sectional area of ​​the inlet is greater than the cross-sectional area of ​​the outlet.

7. A multi-rotor UAV according to claim 6, characterized in that: The air guide groove is trumpet-shaped; or, the cross section of the air guide groove is V-shaped.

8. The multi-rotor UAV according to claim 1, characterized in that: A Laval nozzle is provided at the air outlet.

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