Small four-axis unmanned aerial vehicle integrated forming rack capable of loading high-capacity lithium battery

Abstract

The invention belongs to the field of structural design of unmanned aerial vehicles, particularly relates to a small four-axis unmanned aerial vehicle integrated molding rack capable of loading a high-capacity lithium battery, and provides the following scheme aiming at the problems of contradiction between capacity and volume of an existing battery, insufficient heat dissipation performance, relatively weak shock resistance of a connecting point and relatively poor production economy. Comprising a main machine frame and a frame cover installed at the top of the main machine frame through bolts, a cabin body is formed between the main machine frame and the frame cover, two equipment installation plates used for separating the space of the cabin body are installed in the cabin body, and a battery cabin cover is installed on one side of the main machine frame through bolts; a frame for enhancing the strength is arranged in the main frame, a high-voltage capacity lithium battery can be loaded in the small frame, the heat dissipation problem of electronic equipment such as batteries, flight control and airborne computers can be solved through the structure of the internal cabin, and meanwhile collaborative optimization of light weight and high strength of the frame structure is achieved through the integrated forming technology. Standardized rapid production and manufacturing of the rack are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of UAV structure design, and particularly to a small four-axis UAV integrated frame capable of loading a large-capacity lithium battery. Background Art

[0002] With the rapid development of UAV technology, small four-axis UAVs have been widely used in multiple industries such as aerial photography, agricultural plant protection, logistics distribution, and environmental monitoring due to their advantages of small size, flexibility, and ease of operation. However, currently, small four-axis UAVs are generally limited by volume, weight, material, and processing technology requirements, and the following problems exist: 1. The contradiction between battery capacity and volume: Traditional frame designs are difficult to accommodate large-capacity lithium batteries, resulting in short battery life (usually < 30 minutes). 2. Insufficient heat dissipation performance: High-voltage large-capacity batteries and in-cabin electronic devices generate a high amount of heat during operation, but existing frames lack targeted heat dissipation designs. 3. Weak anti-impact ability of connection points: The connection points of the arm, leg, and fuselage structures are generally weak, and irreversible damage is likely to occur when the UAV falls or collides. 4. Poor production economy: The whole machine has a large number of components and complex assembly steps.

[0003] Therefore, a UAV frame is designed to solve the above problems and has the following effects: 1. It can load high-voltage (≥12S) large-capacity lithium batteries (22000 mAh). 2. Solve the heat dissipation problems of electronic devices such as batteries, flight controllers, and on-board computers. 3. Through an integrated molding process, synergistically optimize the light weight (net weight 1350 g) and high strength (bending strength ≥ 500 MPa) of the frame structure. 4. Through an integrated molding process, achieve standardized and rapid production and manufacturing of the frame, reduce the assembly process, and lower the assembly difficulty. Summary of the Invention

[0004] The purpose of the present invention is to solve the shortcomings of the contradiction between battery capacity and volume, insufficient heat dissipation performance, weak anti-impact ability of connection points, and poor production economy in the prior art, and to propose a small four-axis UAV integrated frame capable of loading a large-capacity lithium battery.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions: A small four-axis UAV integrated frame capable of loading large-capacity lithium batteries, comprising a main frame and a frame cover bolted to the top of the main frame. A cabin is formed between the main frame and the frame cover. Inside the cabin, two equipment mounting plates are installed, both of which are used to partition the space of the cabin. A battery compartment cover is bolted to one side of the main frame. A frame for increasing strength is provided inside the main frame; Landing gear for supporting the frame, which is located at the bottom of the main frame; Arms for installing motors driving the rotors, which are installed on the outer wall of the main frame.

[0006] In a possible design, the main frame is an integrated main frame formed by mixing and laying carbon fiber prepreg and aramid fiber and combining with autoclave curing process.

[0007] In a possible design, rear heat dissipation holes are provided at the rear end of the main frame, and front heat dissipation holes are provided at the bottom of the front end of the main frame.

[0008] In a possible design, two fan mounting holes are provided at the front end of the main frame, both of which are used to install fans to continuously intake air into the cabin.

[0009] In a possible design, a copper-nickel alloy shielding net is embedded in the lower equipment mounting plate to reduce the electromagnetic radiation intensity during battery operation.

[0010] In a possible design, the frame includes two groups of vertical frames and three horizontal frames. The two groups of vertical frames are respectively fixed on the inner walls of both sides of the cabin, and each group of vertical frames has three. The two ends of the horizontal frame are respectively arranged on the outer walls of adjacent two vertical frames. The vertical frames and the horizontal frames are connected by high-temperature glue and rivets. Two reinforcing ribs are fixedly arranged on both sides of the inner wall of the bottom of the cabin. Pure fabric layers are provided on the surfaces of the reinforcing ribs, vertical frames and horizontal frames. Cable through holes are provided on the outer walls of the vertical frames. The lower equipment mounting plate is bolted to the tops of multiple horizontal frames, and the two equipment mounting plates are connected by multiple support rods.

[0011] In a possible design, the arm includes an arm frame, a heat dissipation cover, a bottom plate and a dust-proof ring. The arm frame is fixedly arranged on the outer wall of the main frame, and the arm frame and the main frame are interconnected. The heat dissipation cover is fixedly arranged on the top of the installation cabin of the arm frame. The bottom plate is installed inside the installation cabin of the arm frame. The motor is fixedly installed in the installation cabin of the arm frame and is located below the bottom plate. The dust-proof ring is glued to the bottom of the installation cabin of the arm frame. Two opposing rectangular long through holes are provided on the surface of the bottom plate, and the thickness of the bottom plate is 1mm.

[0012] In a possible design, both the arm frame and the landing gear are integrally formed with the main frame through carbon fiber prepreg and embedded titanium alloy grids by autoclave curing. Titanium alloy grid stiffeners are embedded at the joints of the arm frame and the landing gear with the main frame, and charging cable holes are provided on the surface of the landing gear.

[0013] In a possible design, the flange thickness of the cover is 1 mm, and the cavity height is 38.9 mm.

[0014] In a possible design, the cabin is divided into a ground sensor layer, a battery compartment, a basic avionics equipment layer, and an expansion equipment layer from bottom to top.

[0015] In the present invention, for the integrally formed frame of the small four-axis drone capable of loading large-capacity lithium batteries, through the integrated composite structure, synchronous forming of the carbon fiber main structure and metal parts can be achieved, reducing the subsequent assembly process; In the present invention, for the integrally formed frame of the small four-axis drone capable of loading large-capacity lithium batteries, by installing two fans at the front, the downward wash airflow of the drone's rotor can be utilized to make the hot air discharged from the side and the rear form convection with the external air, making the heat dissipation duct smoother and further improving the heat dissipation effect; In the present invention, this small frame can load high-voltage capacity lithium batteries, and the structure of the internal cabin can solve the heat dissipation problems of electronic devices such as batteries, flight controls, and on-board computers. At the same time, through the integrally formed process, the collaborative optimization of the lightweight and high strength of the frame structure is realized, the standardized and rapid production and manufacturing of the frame are achieved, and the assembly process is reduced and the assembly difficulty is lowered. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a front view structural schematic diagram of an integrally formed frame of a small four-axis drone capable of loading large-capacity lithium batteries proposed by the present invention; Figure 2 It is a rear view structural schematic diagram of an integrally formed frame of a small four-axis drone capable of loading large-capacity lithium batteries proposed by the present invention; Figure 3 It is a sectional structural schematic diagram of an integrally formed frame of a small four-axis drone capable of loading large-capacity lithium batteries proposed by the present invention; Figure 4 It is an exploded structural schematic diagram of an integrally formed frame of a small four-axis drone capable of loading large-capacity lithium batteries proposed by the present invention; Figure 5 For the present invention Figure 4 The enlarged structural diagram of part A in it.

[0017] In the figure: 1. Main frame; 2. Arm; 3. Frame cover; 4. Fan mounting hole; 5. Landing gear; 6. Rear heat dissipation hole; 7. Battery compartment cover; 8. Equipment mounting plate; 9. Front heat dissipation hole; 10. Reinforcing rib; 11. Charging cable hole; 12. Cable through hole; 13. Vertical frame; 14. Horizontal frame; 15. Heat dissipation cover; 16. Bottom plate; 17. Rectangular long through hole; 18. Dustproof ring; 19. Arm frame. Detailed implementation mode

[0018] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0019] Embodiment 1 Refer to Figure 1 , a frame, including: main frame 1, frame cover 3, landing gear 5 and arm 2.

[0020] The main frame 1 is made of a mixed ply of T700 / T800 grade carbon fiber prepreg and aramid fiber, combined with the autoclave curing process to form an integrated main frame, ensuring the high strength and light weight of the frame.

[0021] Refer to Figure 4 , a frame for increasing strength is arranged inside the main frame 1, including two groups of vertical frames 13 and three horizontal frames 14. The two groups of vertical frames 13 are respectively fixedly arranged on the vertical frames 13 on the inner walls on both sides of the cabin body, and each group of vertical frames 13 is provided with three. The two ends of the horizontal frame 14 are respectively arranged on the outer walls of two adjacent vertical frames 13, and the connection between the vertical frame 13 and the horizontal frame 14 is connected by means of high-temperature glue and rivets to form a stable support structure. Two reinforcing ribs 10 are fixedly arranged on both sides of the inner wall of the bottom of the cabin body. Pure fabric plies are arranged on the surfaces of the reinforcing ribs 10, vertical frames 13 and horizontal frames 14, further improving the strength and stability of the frame. Cable through holes 12 are opened on the outer walls of the vertical frames 13, facilitating the arrangement and management of cables.

[0022] One side of the main frame 1 is installed with a battery compartment cover 7 by bolts.

[0023] Refer to Figure 3 , the frame cover 3 is installed on the top of the main frame 1 by bolts, and a cabin body is formed between the frame cover 3 and the main frame 1. Two equipment mounting plates 8 are installed inside the cabin body for separating the cabin body space and facilitating the installation and layout of different equipment. Specifically, the cabin body is divided into a ground sensor layer, a battery compartment, a basic avionics equipment layer and an expansion equipment layer from bottom to top, facilitating the classified installation and management of different equipment. The equipment mounting plate 8 located below is embedded with a copper-nickel alloy shielding net with a coverage rate ≥85%, reducing the electromagnetic radiation intensity during battery operation to ≤30dBμV / m, effectively reducing the electromagnetic radiation intensity during battery operation and improving the communication stability and data transmission quality of the drone.

[0024] Refer to Figure 1 , the landing gear 5 is located at the bottom of the main frame 1 and is used to support the frame. Both the landing gear 5 and the arm 2 are integrally formed with the main frame 1 by means of carbon fiber prepreg and embedded titanium alloy grid through autoclave curing, ensuring the strength and stability of the overall structure. Specifically, the T800 carbon fiber prepreg is laid at alternating angles of 0° / 45° / 90° with the embedded titanium alloy grid and cured at an autoclave temperature of 180°C and a pressure of 0.6 MPa. A titanium alloy grid stiffener 10 is embedded at the connection between the landing gear 5 and the main frame 1, increasing the local torsional stiffness by 50% and further enhancing the strength of the connection. A charging cable hole 11 is provided on the surface of the landing gear 5 to facilitate the passing and connection of the charging cable.

[0025] Specifically, by adopting the technology of embedding stiffeners in the mold, the synchronous molding of the carbon fiber main structure and metal parts is realized, reducing the later assembly process; based on the topology optimization algorithm, the optimal fiber laying path is generated, and the material utilization rate is increased to 95%, and the waste rate < 5%.

[0026] Refer to Figure 5 , the arm 2 is installed on the outer wall of the main frame 1 and is used to install the motor for driving the rotor. The arm 2 includes an arm frame 19, a heat dissipation cover 15, a bottom plate 16 with a thickness of 1 mm, and a dust-proof ring 18. The arm frame 19 is fixedly arranged on the outer wall of the main frame 1 and is interconnected with the main frame 1, facilitating the heat dissipation of the motor and the arrangement of the cables. The heat dissipation cover 15 is fixedly arranged on the top of the installation compartment of the arm frame 19, the bottom plate 16 is installed inside the installation compartment of the arm frame 19, the motor is fixedly installed in the installation compartment of the arm frame 19 and is located below the bottom plate 16. The dust-proof ring 18 is adhesively bonded to the bottom of the installation compartment of the arm frame 19, effectively preventing dust and sundries from entering the installation compartment. Two opposing rectangular long through holes 17 are provided on the surface of the bottom plate 16 to facilitate the heat dissipation of the motor and the arrangement of the wire harness.

[0027] This application can be used in the field of UAV structure design, and can also be used in other fields applicable to this application.

[0028] Embodiment 2 Refer to Figure 1-2 , on the basis of Embodiment 1: A small four-rotor UAV integrated molding frame capable of loading a large-capacity lithium battery, which is applied to the field of UAV structure design. A rear heat dissipation hole 6 is provided at the rear end of the main frame 1. This heat dissipation hole is designed to be fine, improving the heat dissipation performance without significantly reducing the waterproof and dust-proof performance. A front heat dissipation hole 9 is provided at the bottom of the front end, and two fan mounting holes 4 are also provided at the front end for installing fans to continuously intake air into the cabin. By utilizing the downwash airflow of the UAV rotor, the hot air discharged from the side and the rear forms convection with the external air, making the heat dissipation air duct smoother and further improving the heat dissipation effect.

[0029] The flanging thickness of the frame cover 3 is 1 mm, and the cavity height is 38.9 mm, ensuring a reasonable layout of the internal space of the cabin and the installation requirements of the equipment.

[0030] This frame has the following advantages compared with the prior art: 1. The specific strength and specific stiffness of the structure have been significantly improved: The overall weight of the machine is reduced to 1350 g (wheelbase 920 mm), the flexural strength reaches 520 MPa, which is 25% lighter and 40% stronger than the traditional split frame; After taking off with a load of 400 g (takeoff weight 7.6 kg including 3.85 kg battery) and passing the 15-meter free fall test, the structural integrity remains above 90%.

[0031] 2. The loading capacity and heat dissipation performance of large-capacity batteries: Supports typical single 22000 mAh 12S lithium batteries or two 22000 mAh 6S batteries in series (battery compartment size 210 mm * 151 mm * 73 mm), and the flight time is increased to 65 minutes (load 400 g); in the test environment with an external air temperature of 25 °C, the working temperatures of the battery and all electronic devices are below 55 °C.

[0032] 3. Economy: The integrated molding process relatively shortens the production cycle of the frame. During the assembly stage, equipment installation and general assembly can be directly carried out on the frame, significantly shortening the assembly process; 4. Compatibility: The hierarchical structure design of the cabin takes into account the space required for mainstream flight controls and user expansion function modules, and the frame has a wider applicability.

[0033] The schematic drawings in the specification of this application are only for illustrative purposes. The dimensions and shapes of the components shown are not actually limited, but only for a schematic representation. During the actual implementation process, the components can be reasonably configured and adjusted according to specific requirements and actual situations.

[0034] The above is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A small four-axis drone integrated molding frame capable of loading large-capacity lithium batteries, characterized in that Comprising: A main frame (1) and a frame cover (3) bolted to the top of the main frame (1). A cabin is formed between the main frame (1) and the frame cover (3). Inside the cabin, two equipment mounting plates (8) are installed, both of which are used to partition the space of the cabin. On one side of the main frame (1), a battery cabin cover (7) is bolted. Inside the main frame (1), a frame for increasing strength is provided; A landing gear (5) for supporting the frame, and the landing gear (5) is located at the bottom of the main frame (1); An arm (2) for installing a motor driving a rotor, and the arm (2) is installed on the outer wall of the main frame (1).

2. The one-piece frame of a small four-axis drone capable of loading large-capacity lithium batteries according to claim 1, characterized in that The main frame (1) is made of a hybrid laminate of carbon fiber prepreg and aramid fiber, and an integrated main frame is formed by combining an autoclave curing process.

3. The one-piece frame of a small four-axis drone capable of loading large-capacity lithium batteries according to claim 2, characterized in that At the rear end of the main frame (1), a rear heat dissipation hole (6) is provided, and at the bottom of the front end of the main frame (1), a front heat dissipation hole (9) is provided.

4. The integrally formed frame of a small four-axis drone capable of loading large-capacity lithium batteries according to claim 2, characterized in that, At the front end of the main frame (1), two fan mounting holes (4) are provided, both of which are used to install fans to continuously intake air into the cabin.

5. The integrated frame of a small four-axis drone capable of loading a large-capacity lithium battery according to claim 3, characterized in that, The equipment mounting plate (8) located below is embedded with a copper-nickel alloy shielding net to reduce the electromagnetic radiation intensity during battery operation.

6. The one-piece frame of a small four-axis drone capable of loading large-capacity lithium batteries according to claim 1, characterized in that, The frame includes two groups of vertical frames (13) and three horizontal frames (14). The two groups of vertical frames (13) are respectively fixedly arranged on the vertical frames (13) on both inner walls of the cabin, and each group of vertical frames (13) has three. The two ends of the horizontal frame (14) are respectively arranged on the outer walls of two adjacent vertical frames (13). The vertical frames (13) and the horizontal frames (14) are connected by a high-temperature adhesive in cooperation with rivets. On both sides of the inner wall of the bottom of the cabin, two reinforcing ribs (10) are fixedly arranged. Pure fabric laminates are provided on the surfaces of the reinforcing ribs (10), the vertical frames (13), and the horizontal frames (14). Cable through holes (12) are provided on the outer walls of the vertical frames (13). The equipment mounting plate (8) located below is bolted to the tops of multiple horizontal frames (14), and the two equipment mounting plates (8) are connected by multiple support rods.

7. The integrally formed frame of a small four-axis drone capable of loading large-capacity lithium batteries according to claim 1, characterized in that, The arm (2) includes an arm frame (19), a heat dissipation cover (15), a bottom plate (16), and a dust-proof ring (18). The arm frame (19) is fixedly arranged on the outer wall of the main frame (1), and the arm frame (19) and the main frame (1) are interconnected. The heat dissipation cover (15) is fixedly arranged on the top of the installation cabin of the arm frame (19). The bottom plate (16) is installed inside the installation cabin of the arm frame (19). The motor is fixedly installed in the installation cabin of the arm frame (19), and the motor is located below the bottom plate (16). The dust-proof ring (18) is adhesively bonded to the bottom of the installation cabin of the arm frame (19). Two opposing rectangular long through holes (17) are provided on the surface of the bottom plate (16), and the thickness of the bottom plate (16) is 1 mm.

8. The integrated frame of a small four-axis drone capable of loading large-capacity lithium batteries according to claim 7, characterized in that, The machine arm (19) and the landing gear (5) are integrally formed with the main frame (1) by means of carbon fiber prepreg and embedded titanium alloy grids through autoclave curing. Titanium alloy grid stiffeners (10) are embedded at the joints of the machine arm (19) and the landing gear (5) with the main frame (1). Charging cable holes (11) are provided on the surface of the landing gear (5).

9. The integrally formed frame of a small four-axis drone capable of loading a large-capacity lithium battery according to claim 1, characterized in that, The flange thickness of the cover (3) is 1 mm, and the cavity height is 38.9 mm.

10. The integrated frame of a small four-axis drone capable of loading large-capacity lithium batteries according to claim 1, characterized in that, The cabin is divided into a ground sensor layer, a battery compartment, a basic avionics equipment layer, and an expansion equipment layer from bottom to top.

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