Long-endurance oil-powered four-rotor unmanned aerial vehicle
By using anti-collision and center of gravity compensation mechanisms, the problems of fuel sloshing and center of gravity deviation in oil-powered UAVs during long-term flight have been solved, achieving fuel stability and center of gravity compensation, thereby improving the flight stability and payload capacity of the UAV.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-26
- Publication Date
- 2026-03-31
AI Technical Summary
During long-duration operation, fuel sloshing can cause instability and center of gravity deviation in gasoline-powered drones. Existing technologies adjust flight power by adding ballast, but this reduces payload and flight quality.
The design incorporates a collision avoidance mechanism and a center of gravity compensation mechanism. The collision avoidance mechanism stabilizes the fuel through a fuel stabilizer plate, while the center of gravity compensation mechanism compensates for the drone's center of gravity by automatically adjusting the height of the storage plate. The design includes components such as a sliding fuel stabilizer plate, floats, gear transmission, and a compensation motor.
It effectively prevents fuel from colliding with the inner wall of the fuel tank, reduces the deviation of the center of gravity, and improves the flight stability and quality of the drone.
Smart Images

Figure CN121553376B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of unmanned aerial vehicle (UAV) technology, specifically to a long-endurance gasoline-powered quadcopter UAV. Background Technology
[0002] Gasoline-powered drones are professional-grade aircraft powered by aviation fuel, achieving ultra-long flight time and high payload capacity thanks to the high-energy-density fuel. Their core is equipped with a piston or turbojet engine, coupled with an efficient transmission mechanism, enabling continuous operation for hours to tens of hours and easily carrying specialized equipment to perform complex tasks. The airframe utilizes carbon fiber composite materials and a lightweight design, combining structural strength with wind resistance and stability, adapting to harsh environments. Compared to electric motor-powered drones, gasoline-powered drones overcome battery capacity limitations, making them particularly suitable for large-scale agricultural spraying, long-distance inspection, emergency communication relay, and scientific research exploration. Through a modular mounting system, they can quickly switch between mission modules such as cameras, sensors, and fire suppression devices, becoming a highly efficient solution in the industrial drone field.
[0003] During long-duration flight, the fuel level in the tank of a gasoline-powered drone gradually decreases. On the one hand, the vibration generated by the engine causes the fuel in the tank to repeatedly impact the inner wall, affecting the drone's balance. On the other hand, as the fuel level decreases, the drone's center of gravity rises, making it prone to deviating from its intended trajectory. Current solutions typically involve adding ballast to the drone and frequently adjusting its flight power. However, adding ballast reduces the drone's payload capacity and overall flight quality.
[0004] Therefore, based on the above problems, we invented a long-endurance gasoline-powered quadcopter UAV. Summary of the Invention
[0005] To address the shortcomings of existing technologies, this invention provides a long-endurance gasoline-powered quadcopter unmanned aerial vehicle (UAV) to solve the problems mentioned in the background section.
[0006] To achieve the above objectives, the present invention provides the following technical solution: a long-endurance gasoline-powered quadcopter unmanned aerial vehicle (UAV), comprising a main body, a bracket mounted on the main body, a fuel tank installed inside the bracket, the fuel tank being fixedly installed to the lower end of the main body via a mounting plate, an anti-collision mechanism for preventing fuel sloshing inside the fuel tank, the anti-collision mechanism including a fuel stabilizing plate slidably installed inside the fuel tank, a lifting mechanism for raising and lowering the fuel stabilizing plate inside the fuel tank, a floating oil port penetrating through the middle position of the fuel stabilizing plate, a fuel suction head inside the fuel tank, the fuel suction head penetrating through the floating oil port, a float ball slidably sleeved outside the fuel suction head, a cavity inside the mounting plate, a rotating shaft rotatably mounted inside the cavity, and the rotating shaft being externally mounted... The shaft is equipped with a take-up roller and a gear. A rack is slidably installed inside the cavity, and the rack meshes with the gear. A resistor is fixedly installed on the inner wall of the cavity. A variable resistor is installed on the rack, and the variable resistor is in contact with the resistor. Electrodes are installed on both the rack and the resistor, and the two electrodes are electrically connected to the resistor and the variable resistor, respectively. A gathering component is installed inside the cavity. The oil suction head is provided with a rope hole. A traction rope is fixed to the lower end of the float. The traction rope passes through the rope hole, the float, and the gathering component in sequence and is wound around the take-up roller. The oil tank is equipped with a center of gravity compensation mechanism for compensating for the center of gravity of the main body. The anti-collision mechanism and the center of gravity compensation mechanism are connected by a gear set.
[0007] Furthermore, the lifting mechanism includes two grooves located at the top of the oil tank. A bidirectional screw is rotatably installed in the groove, with both ends of the two bidirectional screws rotatably penetrating the oil tank. The two bidirectional screws are connected by a transmission mechanism. Two threaded blocks are threaded onto the external threads of the bidirectional screws. The threaded blocks are slidably connected to the inner wall of the groove. The lower ends of the two threaded blocks are rotatably installed with the same scissor fork. Both lower ends of the scissor fork are rotatably connected to a sliding plate, which is slidably connected to the upper surface of the oil stabilizer plate.
[0008] Furthermore, the transmission mechanism includes two pulleys, which are coaxially mounted with two bidirectional screws, and are connected to each other by a synchronous belt drive.
[0009] Furthermore, the center of gravity compensation mechanism includes a U-shaped plate, which is fixedly installed with a bracket. Multiple vertical plates are fixed to the upper end of the U-shaped plate. The vertical plates are fixed to the oil tank via a stabilizing plate. A lifting hole is provided on each vertical plate, and a lifting screw is rotatably installed within the lifting hole. A transmission cavity is provided within each vertical plate. The upper end of the lifting screw rotatably passes through the vertical plate and extends into the transmission cavity. A compensation motor is installed at the upper end of the vertical plate. The drive shaft of the compensation motor rotatably passes through the vertical plate and is coaxially installed with the lifting screw. Both electrodes are electrically connected to the compensation motor. A shelf is provided above the U-shaped plate, and multiple lifting plates are installed around the periphery of the shelf. The vertical plates slide through the lifting plates, and the lifting screw threadedly passes through the lifting plates.
[0010] Furthermore, the gear set includes a first bevel gear and a second bevel gear that mesh with each other, the first bevel gear being coaxially mounted with the lifting screw, and the bidirectional screw being coaxially mounted with the second bevel gear.
[0011] Furthermore, the lower end face of the oil stabilizing plate is inclined, and the height of the edge position of the oil stabilizing plate is lower than the height of the middle position of the oil stabilizing plate.
[0012] Furthermore, both threaded blocks are provided with threaded holes that match the bidirectional screw, and the threads in the two threaded holes have opposite directions.
[0013] Compared with the prior art, the present invention provides a long-endurance gasoline-powered quadcopter unmanned aerial vehicle (UAV) with the following advantages:
[0014] 1. By setting up an anti-collision mechanism, the height of the fuel stabilizer plate is adjusted according to the fuel level in the drone's fuel tank, so that the fuel stabilizer plate always limits the fuel. When the drone vibrates, the fuel stabilizer plate can stabilize the fuel below, prevent it from fluctuating, and avoid the fuel from violently colliding with the inner wall of the fuel tank, which would affect the drone's flight.
[0015] 2. By setting up a center of gravity compensation mechanism, when the amount of fuel in the fuel tank decreases, the fuel level drops, and the height of the placement plate is automatically adjusted according to the fuel level. On the one hand, the center of gravity of the drone itself gradually rises as the fuel decreases; on the other hand, the center of gravity of the transported items on the placement plate and the placement plate itself decreases, aligning with the center of gravity of the drone. This compensates for the center of gravity of the drone, reduces the deviation of the drone's center of gravity, and improves the flight quality of the drone.
[0016] This application can stabilize the fuel in the fuel tank, preventing it from colliding with the inner wall of the fuel tank. At the same time, it can compensate for the center of gravity of the drone, reduce the deviation of the drone's center of gravity, and improve the flight quality of the drone. Attached Figure Description
[0017] Figure 1This is a schematic diagram of the structure of a long-endurance gasoline-powered quadcopter unmanned aerial vehicle (UAV).
[0018] Figure 2 A frontal structural perspective view of a collision avoidance mechanism in a long-endurance gasoline-powered quadcopter UAV;
[0019] Figure 3 A side perspective view of the collision avoidance mechanism in a long-endurance gasoline-powered quadcopter UAV;
[0020] Figure 4 This is a schematic diagram of the fuel intake head in a long-endurance gasoline-powered quadcopter UAV.
[0021] Figure 5 This is a partial structural diagram of a collision avoidance mechanism in a long-endurance gasoline-powered quadcopter UAV;
[0022] Figure 6 A perspective view of the fuel stabilizer plate in a long-endurance gasoline-powered quadcopter UAV;
[0023] Figure 7 A schematic diagram of a center-of-gravity compensation mechanism for a long-endurance, gasoline-powered quadcopter UAV;
[0024] Figure 8 A partial structural perspective view of a center-of-gravity compensation mechanism for a long-endurance gasoline-powered quadcopter UAV;
[0025] Figure 9 for Figure 8 Enlarged view of point A in the middle.
[0026] In the diagram: 1. Main body; 2. Support frame; 3. Oil tank; 4. Storage plate; 5. Anti-collision mechanism; 6. Center of gravity compensation mechanism; 7. Oil stabilizing plate; 8. Oil floating port; 9. Groove; 10. Bidirectional screw; 11. Threaded block; 12. Transmission mechanism; 13. Pulley; 14. Scissor fork; 15. Slide plate; 16. Mounting plate; 17. Cavity; 18. Oil suction head; 19. Float; 20. Traction rope; 21. Rope hole; 22. Gathering component; 23. Shaft; 24. Take-up roller; 25. Rack; 26. Gear; 27. Resistance element; 28. Electrode; 29. Variable resistance element; 30. Reverse plate; 31. Vertical plate; 32. Lifting plate; 33. Lifting hole; 34. Lifting screw; 35. Compensation motor; 36. Stabilizing plate; 37. Transmission cavity; 38. Gear set; 39. First bevel gear; 40. Second bevel gear. Detailed Implementation
[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0028] As described in the background section, there are shortcomings in the existing technology. In order to solve the above-mentioned technical problems, this application proposes a long-endurance gasoline-powered quadcopter unmanned aerial vehicle.
[0029] like Figures 1-9 As shown, a long-endurance gasoline-powered quadcopter unmanned aerial vehicle includes a main body 1, a bracket 2 mounted on the main body 1, a fuel tank 3 installed inside the bracket 2, the fuel tank 3 being fixedly installed to the lower end of the main body 1 via a mounting plate 16, an anti-collision mechanism 5 for preventing fuel sloshing inside the fuel tank 3, and a center of gravity compensation mechanism 6 for compensating the center of gravity of the main body 1 inside the fuel tank 3. The anti-collision mechanism 5 and the center of gravity compensation mechanism 6 are connected by a gear set 38.
[0030] To prevent fuel from impacting the inner wall of the fuel tank 3 during drone flight, an anti-collision mechanism 5 is installed. This mechanism includes a fuel stabilizing plate 7 slidably installed within the fuel tank 3. Notably, the lower end of the fuel stabilizing plate 7 is inclined, and the height of its edges is lower than the height of its center. This prevents air from entering below the fuel stabilizing plate 7, ensuring it remains stably filled with fuel. The fuel tank 3 includes a lifting mechanism for raising and lowering the fuel stabilizing plate 7. A float port 8 is located through the center of the fuel stabilizing plate 7. A fuel suction head 18 is located within the fuel tank 3, passing through the float port 8. A float ball 19 is slidably fitted around the fuel suction head 18. A cavity 17 is located within the mounting plate 16, and a rotating shaft 23 is rotatably mounted within this cavity. The rotating shaft 23 is connected to the cavity 17 by a spiral spring. The rotating shaft 23 is coaxially mounted with a take-up roller 24 and a gear 26. A rack 25 is slidably mounted inside the cavity 17, and the rack 25 meshes with the gear 26. A resistor 27 is fixedly mounted on the inner wall of the cavity 17. A variable resistor 29 is mounted on the rack 25, and the variable resistor 29 abuts against the resistor 27. Electrodes 28 are mounted on both the rack 25 and the resistor 27. The two electrodes 28 are electrically connected to the resistor 27 and the variable resistor 29, respectively. It should be noted that the current change between the two electrodes 28 is monitored by an external current sensor. When the current change is significantly different, the compensation motor 35 is controlled to drive. A take-up member 22 is installed inside the cavity 17. The oil suction head 18 is provided with a rope hole 21. A traction rope 20 is fixed to the lower end of the float 19. The traction rope 20 passes through the rope hole 21, the float 19, and the take-up member 22 in sequence and is wound around the take-up roller 24.
[0031] In this invention, the lifting mechanism includes two grooves 9 located at the top of the oil tank 3. A bidirectional screw 10 is rotatably installed within the grooves 9, with both ends of the two bidirectional screws 10 rotatably penetrating the oil tank 3. The two bidirectional screws 10 are connected by a transmission mechanism 12. Notably, the transmission mechanism 12 includes two pulleys 13, which are coaxially mounted with the two bidirectional screws 10 respectively. The two pulleys 13 are connected by a synchronous belt. Two threaded blocks 11 are threaded onto the external threads of the bidirectional screws 10. Furthermore, each threaded block 11 has a threaded hole matching the bidirectional screw 10, with the threads in the two threaded holes rotating in opposite directions. The threaded blocks 11 are slidably connected to the inner wall of the grooves 9. A scissor fork 14 is rotatably installed at the lower ends of the two threaded blocks 11. Slide plates 15 are rotatably connected to the two lower ends of the scissor fork 14, and the slide plates 15 are slidably connected to the upper surface of the oil stabilizing plate 7.
[0032] Through the above technical features: when the oil level in the tank 3 decreases and the oil level drops, the float 19 descends under the action of buoyancy. At this time, the rotating shaft 23 rotates under the winding action of the spiral spring. The rotating shaft 23 drives the winding roller 24 to rotate, and the winding roller 24 winds up the loosened traction rope 20. Simultaneously, the rotating shaft 23 drives the gear 26 to rotate, the gear 26 drives the rack 25 to move, and the rack 25 drives the variable resistance plate 29 to move. At this time, the resistance between the two electrodes 28 changes, causing the current of the compensation motor 35 to change. At this time, the compensation motor 35 drives the lifting screw 34 to rotate. The lifting screw 34 drives the bidirectional screw 10 to rotate, and the bidirectional screw 10 drives the threaded block 11 to move. The threaded block 11 drives the fuel stabilizer plate 7 to rise and fall through the scissor fork 14 until it reaches the appropriate position, so that the amount of fuel below the fuel stabilizer plate 7 just covers the upper opening of the float port 8. When the drone vibrates, the fuel located below the fuel stabilizer plate 7 is blocked by the fuel stabilizer plate 7, and the fuel will not collide with the inner wall of the fuel tank 3. Due to the vibration, less fuel flows to the top of the fuel stabilizer plate 7, and the collision is unlikely to affect the normal flight of the drone, thus avoiding the drone's flight being affected by the collision between the fuel and the inner wall of the fuel tank 3.
[0033] To compensate for the center of gravity of the drone, a center of gravity compensation mechanism 6 is provided. The center of gravity compensation mechanism 6 includes a return plate 30, which is fixedly installed with the bracket 2. Multiple vertical plates 31 are fixed to the upper end of the return plate 30. The vertical plates 31 are fixed to the oil tank 3 through the stabilizing plate 36. The vertical plates 31 are provided with lifting holes 33. A lifting screw 34 is rotatably installed in the lifting holes 33. A transmission cavity 37 is provided in the vertical plates 31. The upper end of the lifting screw 34 rotatably passes through the vertical plates 31 and extends into the transmission cavity 37. A compensation motor 35 is installed at the upper end of the vertical plates 31. The drive shaft of the compensation motor 35 rotatably passes through the vertical plates 31 and is coaxially installed with the lifting screw 34. Both electrodes 28 are electrically connected to the compensation motor 35. A shelf 4 is provided above the return plate 30. Multiple lifting plates 32 are installed around the periphery of the shelf 4. The vertical plates 31 slide through the lifting plates 32. The lifting screw 34 threadedly passes through the lifting plates 32.
[0034] It should be noted that the gear set 38 includes a first bevel gear 39 and a second bevel gear 40 that mesh with each other. The first bevel gear 39 is coaxially mounted with the lifting screw 34, and the bidirectional screw 10 is coaxially mounted with the second bevel gear 40.
[0035] Through the above technical features: when the fuel quantity decreases, the drive shaft of the compensation motor 35 drives the lifting screw 34 to rotate, the lifting screw 34 drives the lifting plate 32 to rise and fall, and the lifting plate 32 drives the placement plate 4 to fall. At this time, the conveyed items placed on the placement plate 4 fall, the overall center of gravity is lowered, and it is aligned with the center of gravity of the drone itself, reducing the deviation of the drone's center of gravity, preventing the drone from deviating from the predetermined flight path, and improving the flight quality of the drone.
[0036] Working principle:
[0037] Fuel anti-collision: When the fuel level in fuel tank 3 decreases, the float 19 descends under buoyancy. At this time, the rotating shaft 23 rotates under the winding action of the spiral spring. The rotating shaft 23 drives the winding roller 24 to rotate, and the winding roller 24 winds up the loosened traction rope 20. Simultaneously, the rotating shaft 23 drives the gear 26 to rotate, the gear 26 drives the rack 25 to move, and the rack 25 drives the variable resistance plate 29 to move. At this time, the resistance between the two electrodes 28 changes, causing a change in the current of the compensation motor 35. The compensation motor 35 then drives the lifting screw 34 to rotate, raising... The lowering screw 34 drives the bidirectional screw 10 to rotate, and the bidirectional screw 10 drives the threaded block 11 to move. The threaded block 11 drives the fuel stabilizer plate 7 to rise and fall through the scissor fork 14 until it reaches the appropriate position, so that the amount of fuel below the fuel stabilizer plate 7 just covers the upper opening of the float port 8. When the drone vibrates, the fuel located on the lower side of the fuel stabilizer plate 7 is blocked by the fuel stabilizer plate 7, and the fuel will not collide with the inner wall of the fuel tank 3. Due to the vibration, less fuel flows to the upper part of the fuel stabilizer plate 7, and the collision is unlikely to affect the normal flight of the drone, thus avoiding the drone's flight being affected by the collision between the fuel and the inner wall of the fuel tank 3.
[0038] Stable center of gravity: When the fuel level decreases, the drive shaft of the compensation motor 35 drives the lifting screw 34 to rotate. The lifting screw 34 drives the lifting plate 32 to rise and fall. The lifting plate 32 drives the placement plate 4 to fall. At this time, the conveyor placed on the placement plate 4 falls, the overall center of gravity is lowered, and it is neutralized with the center of gravity of the drone itself. This reduces the deviation of the drone's center of gravity, prevents the drone from deviating from the predetermined flight path, and improves the flight quality of the drone.
[0039] It should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.
[0040] The detailed descriptions listed above are merely specific descriptions of feasible implementation methods of this application and are not intended to limit the scope of protection of this application. All equivalent implementation methods or modifications made without departing from the spirit of the art of this application should be included within the scope of protection of this invention.
Claims
1. A long endurance oil-powered quadcopter drone, characterized in that: The utility model provides an oil tank with anti-sloshing mechanism, which belongs to the technical field of oil tank and comprises a body (1), a support (2) mounted on the body (1), an oil tank (3) mounted in the support (2), and a mounting plate (16) for fixing the oil tank (3) to the lower end of the body (1). The oil tank (3) is provided with an anti-collision mechanism (5) for preventing fuel from sloshing. The anti-collision mechanism (5) comprises a stabilizing plate (7) slidably mounted in the oil tank (3). The oil tank (3) is provided with a lifting mechanism for lifting and lowering the stabilizing plate (7). The stabilizing plate (7) is provided with a floating oil port (8) at the middle position. The oil tank (3) is provided with a suction head (18) penetrating through the floating oil port (8). The suction head (18) is slidably sleeved with a float (19). The mounting plate (16) is provided with a cavity (17). A rotating shaft (23) is rotatably mounted in the cavity (17). A winding roller (24) and a gear (26) are coaxially mounted on the rotating shaft (23). A rack (25) is slidably mounted in the cavity (17). The rack (25) is in meshing connection with the gear (26). An electric resistance sheet (27) is fixedly mounted on the inner wall of the cavity (17). A variable resistance sheet (29) is mounted on the rack (25) and in abutting contact with the electric resistance sheet (27). Electrodes (28) are mounted on the rack (25) and the electric resistance sheet (27). The two electrodes (28) are in electrical connection with the electric resistance sheet (27) and the variable resistance sheet (29), respectively. A folding member (22) is mounted in the cavity (17). The suction head (18) is provided with a rope penetrating hole (21). The lower end of the float (19) is fixedly provided with a traction rope (20). The traction rope (20) penetrates through the rope penetrating hole (21), the float (19), and the folding member (22) in sequence and is wound on the winding roller (24). The oil tank (3) is provided with a gravity compensation mechanism (6) for compensating the gravity of the body (1). The anti-collision mechanism (5) and the gravity compensation mechanism (6) are in driving connection through a gear set (38). The lifting mechanism comprises two grooves (9) arranged at the top of the oil tank (3). A bidirectional screw rod (10) is rotatably mounted in each groove (9). The two ends of each bidirectional screw rod (10) are rotatably penetrated through the oil tank (3). The two bidirectional screw rods (10) are in driving connection through a transmission mechanism (12). The bidirectional screw rod (10) is externally threadedly sleeved with two threaded blocks (11). The threaded blocks (11) are in sliding connection with the inner wall of the groove (9). The lower ends of the two threaded blocks (11) are rotatably mounted with the same scissor fork (14). The two lower ends of the scissor fork (14) are rotatably connected with sliding plates (15). The sliding plates (15) are in sliding connection with the upper end surface of the stabilizing plate (7). The gravity compensation mechanism (6) comprises a back-shaped plate (30) fixedly installed with the support (2), a plurality of vertical plates (31) fixed to the upper end of the back-shaped plate (30), the vertical plates (31) fixed with the oil tank (3) through a stabilizing plate (36), the vertical plates (31) provided with lifting holes (33), the lifting holes (33) rotatably installed with lifting screws (34), the vertical plates (31) provided with transmission cavities (37), the upper ends of the lifting screws (34) rotatably penetrating through the vertical plates (31) and extending into the transmission cavities (37), the upper ends of the vertical plates (31) installed with compensation motors (35), the driving shafts of the compensation motors (35) rotatably penetrating through the vertical plates (31) and coaxially installed with the lifting screws (34), the two electrodes (28) electrically connected with the compensation motors (35), the upper side of the back-shaped plate (30) provided with a storage plate (4), the storage plate (4) installed with a plurality of lifting pieces (32) on the circumferential side, the vertical plates (31) slidably penetrating through the lifting pieces (32), the lifting screws (34) threadedly penetrating through the lifting pieces (32). The lower end surface of the oil stabilizing plate (7) is obliquely arranged, and the height of the edge position of the oil stabilizing plate (7) is lower than that of the middle position of the oil stabilizing plate (7).
2. The long endurance oil-powered quadcopter unmanned aerial vehicle according to claim 1, wherein: The transmission mechanism (12) comprises two belt pulleys (13), the two belt pulleys (13) coaxially installed with the two bidirectional screws (10), and the two belt pulleys (13) connected through a synchronous belt transmission.
3. The long endurance oil-powered quadcopter unmanned aerial vehicle according to claim 1, wherein: The gear set (38) comprises a first bevel gear (39) and a second bevel gear (40) meshing with each other, the first bevel gear (39) coaxially installed with the lifting screw (34), and the bidirectional screw (10) coaxially installed with the second bevel gear (40).
4. The long endurance oil-powered quadcopter unmanned aerial vehicle according to claim 3, wherein: The two threaded blocks (11) are provided with threaded holes matched with the bidirectional screws (10), and the threads in the two threaded holes are opposite in rotation direction.
Citation Information
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