Fuselage-fuel tank integrated structure suitable for ejection type unmanned aerial vehicle

Abstract

The utility model relates to the technical field of unmanned aerial vehicle structural design, in particular to a fuselage-fuel tank integrated structure suitable for an ejection type unmanned aerial vehicle, which comprises a fuel tank assembly, a fuselage skin and a fuselage shell with a wing root, and the fuselage shell with the wing root adopts a wall plate type structure; the oil tank assembly comprises a main oil tank, a left front sub-oil tank, a right front sub-oil tank and a rear sub-oil tank which are arranged on the machine body shell, adjacent oil tanks in the main oil tank, the left front sub-oil tank, the right front sub-oil tank and the rear sub-oil tank are connected, and the right front sub-oil tank, the rear sub-oil tank, the left front sub-oil tank and the main oil tank are sequentially communicated and then communicated with an engine through a small oil can. The fuselage skin is used for connecting a wall plate of the fuselage shell, the main oil tank, the left front sub-oil tank, the right front sub-oil tank and the rear sub-oil tank to form a fuselage-oil tank integrated structure; catapulting fulcrums are arranged on the fuselage skin corresponding to the bottoms of the wing roots. The oil supply device can supply oil safely and stably while meeting the strength and rigidity requirements of catapult-assisted take-off of the unmanned aerial vehicle.

Description

Technical Field

[0001] This utility model relates to the field of unmanned aerial vehicle (UAV) structural design technology, specifically to an integrated fuselage-fuel tank structure suitable for catapult-launched UAVs. Background Technology

[0002] Catapult takeoff has become one of the most widely adopted takeoff methods for small fixed-wing UAVs because it does not require a runway, has lower requirements for takeoff sites, and the catapult device can be reused, greatly reducing operating and maintenance costs. However, because catapult takeoff has a higher overload than runway takeoff and rocket-assisted takeoff, this takeoff method also poses significant challenges to the structural strength of the UAV's fuselage and the stable and safe fuel supply of the fuel system.

[0003] The fuselage of a drone connects components such as wings, tail, engines, and landing gear into a single unit, bearing the loads of each component and thus forming the foundation for the entire drone's stress distribution. To meet structural strength and rigidity requirements, traditional drone fuselage structures consist of stringers, beams, frames, and skin, resulting in a complex construction and high production costs.

[0004] Furthermore, existing drone fuel tanks are mostly made of metal or plastic. Metal materials are relatively heavy and unsuitable for small drones, and most are welded, which can easily lead to oil leaks at the welds after repeated ejection launches. Metal is also prone to rust and corrosion. Plastic structures have lower strength and obviously do not meet the requirements for ejection launches. In summary, for ejection-launched drones, in order to ensure sufficient fuel capacity and a safe and stable fuel supply, the fuel tank structure needs to address the following issues: how to design a lightweight fuel tank while ensuring that the tank structure meets the strength and rigidity requirements for ejection launch.

[0005] Therefore, there is a need to provide an integrated fuselage-fuel tank structure suitable for catapult-launched UAVs to solve the above problems. Utility Model Content

[0006] This invention provides an integrated fuselage-fuel tank structure suitable for catapult-launched UAVs, to solve the existing problem of how to design a lightweight fuel tank while ensuring that the fuel tank structure meets the strength and rigidity requirements for catapult takeoff.

[0007] The present invention provides an integrated fuselage-fuel tank structure for catapult-launched unmanned aerial vehicles, which adopts the following technical solution, including:

[0008] The fuselage shell has wing roots and adopts a panel structure;

[0009] The fuel tank assembly includes: a main fuel tank located in the middle of the fuselage housing, a left front sub-fuel tank at the left front, a right front sub-fuel tank at the right front, and a rear sub-fuel tank at the rear. The main fuel tank, the left front sub-fuel tank, the right front sub-fuel tank, and the rear sub-fuel tank are connected to each other. The right front sub-fuel tank, the rear sub-fuel tank, the left front sub-fuel tank, and the main fuel tank are connected in sequence and then connected to the engine through a small oil reservoir.

[0010] And the fuselage skin, which is used to connect the fuselage shell, main fuel tank, left front sub-fuel tank, right front sub-fuel tank and rear sub-fuel tank to form an integrated fuselage-fuel tank structure;

[0011] Among them, ejection fulcrums are set on the fuselage skin corresponding to the bottom of the wing root.

[0012] Preferably, the fuselage housing is bonded to the main fuel tank, the left front sub-fuel tank, the right front sub-fuel tank, and the rear sub-fuel tank, and adjacent fuel tanks among the main fuel tank, the left front sub-fuel tank, the right front sub-fuel tank, and the rear sub-fuel tank are bonded together with epoxy resin.

[0013] Preferably, the left front sub-fuel tank and the right front sub-fuel tank are located in front of the center of gravity of the fuselage and are symmetrically arranged, while the rear sub-fuel tank is located behind the center of gravity of the fuselage.

[0014] Preferably, the main fuel tank is equipped with a low fuel level alarm sensor, which is used to monitor the fuel level in the UAV's fuel tank.

[0015] Preferably, the small oil can is equipped with an oil filling pipe, and the free end of the oil filling pipe is equipped with an oil filling connector.

[0016] Preferably, the end of the wing root is provided with an interface for connecting to the wing.

[0017] Preferably, the side of the left front sub-fuel tank and the right front sub-fuel tank closest to the fuselage housing has the same shape as the side panel.

[0018] Preferably, the main fuel tank is also connected to an engine return fuel line.

[0019] Preferably, both the fuselage housing and the fuel tank assembly are made of composite materials.

[0020] The beneficial effects of this utility model are:

[0021] 1. By setting the fuselage shell with wing roots as a panel structure, that is, the fuselage shell has no stringers, beams and bulkheads, the construction is simple. The individual fuel tanks of the fuselage shell and fuel tank assembly are manufactured separately and independently. Both the fuselage shell and fuel tank assembly are made of composite materials, which makes the overall structure lightweight and high-strength. Then they are bonded together to form an integrated load-bearing structure. At the same time, ejection fulcrums are set on the fuselage skin corresponding to the bottom of the wing roots to meet the strength and rigidity requirements of UAV ejection takeoff and reduce manufacturing difficulty.

[0022] 2. The fuel tank structure of this utility model can realize that each fuel tank consumes fuel in sequence, and the fuel consumption has little impact on the center of gravity of the UAV, hardly affecting the operation of the UAV, and will not affect flight safety. Furthermore, due to the setting of the fuel tank components of this utility model, the main fuel tank will not affect the fuel supply to the engine when the UAV changes its flight attitude, thus minimizing the risk of engine stall. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the overall structure of an integrated fuselage-fuel tank structure suitable for catapult-launched unmanned aerial vehicles (UAVs) according to this utility model.

[0025] Figure 2 This is a rear view of an integrated fuselage-fuel tank structure suitable for catapult-launched unmanned aerial vehicles (UAVs) according to this utility model.

[0026] Figure 3 This is a connection principle diagram of a fuel tank assembly with an integrated fuselage-fuel tank structure suitable for catapult-launched UAVs according to this utility model;

[0027] Figure 4 This is a schematic diagram of the main oil tank in an embodiment of the present invention.

[0028] In the diagram: 1. Fuselage; 2. Main fuel tank; 3. Front left sub-fuel tank; 4. Front right sub-fuel tank; 5. Rear sub-fuel tank; 6. Fuel tank connecting pipe; 7. Engine return fuel pipe; 8. Small fuel can inlet pipe; 9. Small fuel can; 10. Fuel filler connector; 11. Fuel filler connector; 12. Engine fuel inlet pipe; 13. Low fuel level alarm sensor; 14. Ejection fulcrum. Detailed Implementation

[0029] 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.

[0030] One embodiment of this utility model is a fuselage-fuel tank integrated structure suitable for catapult-launched unmanned aerial vehicles, such as... Figure 1 As shown, it includes: fuel tank assembly, fuselage skin and fuselage shell 1 with wing roots. The fuselage shell 1 with wing roots adopts a panel structure, that is, the fuselage shell 1 with panel structure has no stringers, beams and bulkheads, and the construction is simple. The fuselage 1 can be divided into two or more panels according to the process technology and requirements to facilitate the installation of the fuel tank assembly, thereby reducing manufacturing difficulty. The fuel tank assembly includes: a main fuel tank 2 located in the middle of the fuselage shell 1, a left front sub-fuel tank 3 at the left front, a right front sub-fuel tank 4 at the right front, and a rear sub-fuel tank 5 at the rear. Adjacent fuel tanks among the main fuel tank 2, left front sub-fuel tank 3, right front sub-fuel tank 4, and rear sub-fuel tank 5 are connected. The right front sub-fuel tank 4, rear sub-fuel tank 5, left front sub-fuel tank 3, and main fuel tank 2 are sequentially connected and then connected to the engine through a small fuel reservoir 9. The fuselage skin is used to connect the panels of the fuselage shell 1, the main fuel tank 2, the left front sub-fuel tank 3, the right front sub-fuel tank 4, and the rear sub-fuel tank 5 to form an integrated fuselage-fuel tank structure. Figure 2 As shown, a catapult fulcrum 14 is provided on the fuselage skin corresponding to the bottom of the wing root, which provides the main load-bearing point for the fuselage shell 1 when the UAV is launched.

[0031] like Figure 3 As shown in the diagram, the fuel tank assembly is connected to the small oil reservoir 9 via an oil pipe in this embodiment. Figure 3 The sequence shown is achieved by connecting the fuel tanks via the fuel tank connection pipe 6, thereby enabling communication between fuel tanks and between the fuel tanks and the engine. The small fuel can 9 is connected to the fuel filler connector 11 via the fuel filler pipe 10, and the small fuel can 9 is also connected to the engine fuel inlet pipe 12 to supply fuel to the engine. The engine return fuel pipe 7 is connected to the bottom of the main fuel tank 2. The bottom of the main fuel tank 2 is connected to the small fuel can 9 via the small fuel can inlet pipe 8. The bottom of the left front sub-fuel tank 3 is connected to the upper part of the main fuel tank 2 via a fuel pipe. The bottom of the rear sub-fuel tank 5 is connected to the upper part of the left front sub-fuel tank 3 via a fuel pipe. The bottom of the right front sub-fuel tank 4 is connected to the upper part of the rear sub-fuel tank 5 via a fuel pipe. The upper part of the right front sub-fuel tank 4 is connected to the outside atmosphere via a pipe.

[0032] To ensure the airtightness of the fuel tank assembly and reduce manufacturing costs, in this embodiment, the fuselage shell 1, right front sub-fuel tank 4, rear sub-fuel tank 5, left front sub-fuel tank 3, and main fuel tank 2 are manufactured independently. The fuselage shell 1 is then bonded to the main fuel tank 2, left front sub-fuel tank 3, right front sub-fuel tank 4, and rear sub-fuel tank 5, and adjacent fuel tanks among the main fuel tank 2, left front sub-fuel tank 3, right front sub-fuel tank 4, and rear sub-fuel tank 5 are bonded together using epoxy resin. It should be noted that in this embodiment, the fuel tank assembly and the wall panels of the fuselage shell 1 are connected using epoxy adhesive, eliminating the need for fasteners. After bonding, the fuel tank assembly and the fuselage shell 1 become an integrated load-bearing structure. This embodiment has been successfully applied to a certain type of UAV. Test results show that the structure of this invention can meet the strength and stiffness requirements during catapult launch and exhibits excellent load-bearing characteristics under tensile, compressive, bending, and torsional load conditions.

[0033] The shape and arrangement of each fuel tank in the fuel tank assembly of this utility model can be designed according to the internal cavity shape of the UAV's fuselage hull 1. The shape and number of fuel tanks are not limited; however, to maximize the UAV's endurance, the space utilization rate of the internal cavity should be improved as much as possible. Specifically, for example... Figure 1 As shown, the left front sub-fuel tank 3 and the right front sub-fuel tank 4 have the same shape as the side panel near the fuselage shell 1. In this embodiment of the invention, the UAV fuel tank is divided into a main fuel tank 2 and three smaller sub-fuel tanks (left front sub-fuel tank 3, right front sub-fuel tank 4, and rear sub-fuel tank 5) to reduce manufacturing difficulty and cost.

[0034] like Figure 1 As shown, the left front sub-fuel tank 3 and the right front sub-fuel tank 4 are located in front of the center of gravity of the fuselage housing 1 and are symmetrically arranged, while the rear sub-fuel tank 5 is located behind the center of gravity of the fuselage housing 1.

[0035] like Figure 1 and 4 As shown, a low fuel level alarm sensor 13 is installed on the side of the main fuel tank 2 near the rear sub-fuel tank 5. The low fuel level alarm sensor 13 is used to monitor the fuel level in the UAV's fuel tank. The main fuel tank 2 has a symmetrical structure and is arranged in the middle of the fuselage shell 1 and the connection area between the wing root and the fuselage, which can better bear the load of the wing and the fuselage.

[0036] Specifically, the end of the wing root is provided with an interface for connecting to the wing.

[0037] Specifically, both the fuselage shell 1 and the fuel tank assembly are made of carbon fiber composite material. The use of this composite material makes the overall structure lightweight and high-strength, meeting the requirements of the UAV catapult takeoff under high overload conditions.

[0038] Working principle

[0039] During refueling, connect the external refueling equipment via refueling connector 11, and proceed according to... Figure 3 The connection diagram shows the fuel line sequence as follows: fuel filler connector 11 → small fuel can 9 → main fuel tank 2 → left front sub-tank 3 → rear sub-tank 5 → right front sub-tank 4. That is, after the main fuel tank 2 is full, the left front sub-tank 3 begins filling; after the left front sub-tank 3 is full, the rear sub-tank 5 begins filling… and when the right front sub-tank 4 is full, all fuel tanks are filled.

[0040] When the drone is flying in the air, according to Figure 3 The connection diagram shows the fuel supply sequence as follows: front right sub-tank 4 → rear sub-tank 5 → front left sub-tank 3 → main fuel tank 2 → small fuel can 9 → engine → fuel return line 7 → main fuel tank 2 (fuel return). This means that when the drone is flying continuously, the fuel in the front right sub-tank 4 will be depleted first, followed by the rear sub-tank 5 and the front left sub-tank 3, with the main fuel tank 2 being the last to run out. Before the fuel in the front left sub-tank 3 is depleted, the main fuel tank 2 remains full. Therefore, even if the drone flies at a large angle and its flight attitude changes, it will not affect the fuel supply from the main fuel tank 2 to the engine, preventing engine stalling. Another benefit of fuel consumption in this order is that, in this embodiment, the fuel consumption order in the fuel tank assembly is right to left, front to back, and finally, the fuel in the main fuel tank 2 is consumed. Since the main fuel tank 2 is located near the center of gravity of the drone, although the amount and distribution of fuel in the tanks change as the drone flies, the fuel consumption has little impact on the position of the drone's center of gravity, hardly affecting the drone's operation, and certainly not affecting the drone's flight safety.

[0041] After the drone is recovered, if there is still fuel in the fuel tank, the fuel pumping equipment can be connected through the fuel filler connector 11 to perform the fuel pumping operation. The fuel line sequence is: right front sub-fuel tank 4 → rear sub-fuel tank 5 → left front sub-fuel tank 3 → main fuel tank 2 → small fuel can 9 → fuel pumping equipment.

[0042] In summary, this invention provides an integrated fuselage-fuel tank structure suitable for catapult-launched UAVs, which meets the strength and rigidity requirements for UAV catapult takeoff, provides a safe and stable fuel supply method and sufficient fuel capacity, and reduces manufacturing difficulty and cost.

[0043] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A fuselage-fuel tank integrated structure suitable for catapult-launched unmanned aerial vehicles, characterized in that, include: The fuselage shell (1) with wing roots adopts a panel structure; The fuel tank assembly includes: a main fuel tank (2) located in the middle of the fuselage housing (1), a left front sub-fuel tank (3) at the left front, a right front sub-fuel tank (4) at the right front, and a rear sub-fuel tank (5) at the rear. The adjacent fuel tanks in the main fuel tank (2), the left front sub-fuel tank (3), the right front sub-fuel tank (4), and the rear sub-fuel tank (5) are connected to each other. The right front sub-fuel tank (4), the rear sub-fuel tank (5), the left front sub-fuel tank (3), and the main fuel tank (2) are connected in sequence and then connected to the engine through a small oil can (9). And the fuselage skin, which is used to connect the wall panel of the fuselage shell (1), the main fuel tank (2), the left front sub-fuel tank (3), the right front sub-fuel tank (4) and the rear sub-fuel tank (5) to form an integrated fuselage-fuel tank structure; Among them, ejection fulcrums (14) are provided on the fuselage skin corresponding to the bottom of the wing root.

2. The integrated fuselage-fuel tank structure for catapult-launched unmanned aerial vehicles according to claim 1, characterized in that, The fuselage housing (1) is bonded to the main fuel tank (2), the left front sub-fuel tank (3), the right front sub-fuel tank (4), and the rear sub-fuel tank (5) with epoxy resin.

3. The integrated fuselage-fuel tank structure for catapult-launched unmanned aerial vehicles according to claim 1, characterized in that, The left front sub-fuel tank (3) and the right front sub-fuel tank (4) are located in front of the center of gravity of the fuselage shell (1) and are symmetrically arranged, while the rear sub-fuel tank (5) is located behind the center of gravity of the fuselage shell (1).

4. The integrated fuselage-fuel tank structure for catapult-launched unmanned aerial vehicles according to claim 1, characterized in that, The main fuel tank (2) is equipped with a low fuel level alarm sensor (13), which is used to monitor the fuel level in the UAV's fuel tank.

5. The integrated fuselage-fuel tank structure for catapult-launched unmanned aerial vehicles according to claim 1, characterized in that, The small oil can (9) is equipped with an oil filling pipe (10), and the free end of the oil filling pipe (10) is equipped with an oil filling connector (11).

6. The integrated fuselage-fuel tank structure for catapult-launched unmanned aerial vehicles according to claim 1, characterized in that, The end of the wing root is provided with an interface for connecting to the wing.

7. The integrated fuselage-fuel tank structure for catapult-launched unmanned aerial vehicles according to claim 1, characterized in that, The left front sub-fuel tank (3) and the right front sub-fuel tank (4) have the same shape as the side panel of the fuselage housing (1) near the side panel.

8. The integrated fuselage-fuel tank structure for catapult-launched unmanned aerial vehicles according to claim 1, characterized in that, The main fuel tank (2) is also connected to the engine return oil pipe (7).

9. The integrated fuselage-fuel tank structure for catapult-launched unmanned aerial vehicles according to claim 1, characterized in that, Both the fuselage shell (1) and the fuel tank assembly are made of composite materials.

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