Coaxial double-rotor unmanned helicopter for loading

Abstract

The invention relates to a coaxial dual-rotor unmanned helicopter for loading. The coaxial dual-rotor unmanned helicopter comprises a frame module; the engine module comprises two engines, and the two engines are arranged on the frame module in a bilateral symmetry mode; the rotor wing module comprises a main shaft as well as an upper rotor wing and a lower rotor wing which are mounted on the main shaft; the rotor attitude control module is mounted on the main shaft, is in transmission connection with the upper rotor and the lower rotor and is used for controlling the flight attitudes of the upper rotor and the lower rotor; and the reduction gearbox module is arranged between the engine module and the main shaft and is used for changing the rotating torsion of the output shafts of the two engines to a rotor wing transmission shaft on the main shaft in the vertical direction. According to the unmanned helicopter, coaxial double-rotor design is adopted in rotor parts, empennages are omitted, synchronous elevation angle adjustment and fuselage posture adjustment of upper and lower layers of propellers can be synchronously achieved, symmetrical layout is adopted in overall power design, the stability of the unmanned helicopter is improved, the load capacity of the unmanned helicopter reaches one ton, the application range is wide, and the unmanned helicopter is suitable for large-scale popularization and application. And the blank of the domestic load-carrying unmanned aerial vehicle is filled.

Description

Technical Field

[0001] The invention relates to the technical field of unmanned helicopters, in particular to a load-carrying coaxial twin-rotor unmanned helicopter. Background Art

[0002] As one of the most distinctive creations of aviation technology in the 20th century, helicopters have greatly expanded the scope of application of aircraft. Helicopters are typical dual-use products that can be widely used in transportation, patrol, tourism, rescue and other fields.

[0003] In the existing technology, such as the Chinese patent with publication number CN111071437A, a multifunctional full-load helicopter with a tail pusher is disclosed, including a helicopter landing gear, a helicopter shell, a transmission system, a spraying system, a cabin and a control system. The cabin of the present invention is arranged in the helicopter shell. When it is necessary to spray pesticides on crops, the spraying system is installed. When cargo is needed, the spraying system can be removed, which effectively improves the application scenario of the helicopter; the transmission system is arranged in such a way that the transmission system uses two main blades (right blade and left blade) to control the lifting and lowering of the helicopter, and a tail rotor to control the propulsion of the helicopter.

[0004] The above-mentioned prior art solutions have the following defects: although the above-mentioned full-load helicopter is equipped with a spraying system and can be used to spray pesticides on crops, it is similar to the driving principle of traditional helicopters, which are driven by the main wing propeller above and controlled by the blades at the tail. Since the left blade and the right blade are symmetrically arranged on both sides of the top of the helicopter shell, and the tail blade is arranged on the side of the left blade away from the right blade, it is inevitable that the center of gravity of the whole body is offset toward the side of the tail blade, making the helicopter flight stability poor and reducing the safety of flight. In addition, this main wing plus tail structure mode affects the weight and load capacity of civil unmanned helicopters. Usually, the weight of civil unmanned helicopters is less than 100 kilograms and the load capacity is less than 10 kilograms, which greatly limits the scope of use of civil unmanned helicopters and affects the promotion and application of unmanned helicopters. Summary of the invention

[0005] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a coaxial twin-rotor unmanned helicopter for load-bearing. The coaxial twin-rotor design is adopted in the rotor part, the tail wing is cancelled, and the synchronous elevation adjustment of the upper and lower propellers and the fuselage attitude adjustment can be realized simultaneously through a full differential control mechanism and a rudder control mechanism. The overall power design adopts a symmetrical layout, which optimizes the center of gravity design of the entire unmanned helicopter to the greatest extent. This structure will greatly improve the stability of the unmanned helicopter. In addition, the unmanned helicopter has a load capacity of one ton and a wide range of applications, filling the gap in domestic load-bearing UAVs.

[0006] The above-mentioned object of the present invention is achieved through the following technical solutions:

[0007] A load-carrying coaxial twin-rotor unmanned helicopter, comprising:

[0008] Framework module;

[0009] The engine module comprises two engines, and the two engines are arranged symmetrically on the frame module;

[0010] A rotor module, comprising a main shaft and an upper rotor and a lower rotor mounted on the main shaft;

[0011] A rotor attitude control module, mounted on the main shaft and respectively connected to the upper rotor and the lower rotor in transmission, for controlling the flight attitude of the upper rotor and the lower rotor;

[0012] The reduction box module is installed between the engine module and the main shaft, and is used to change the rotational torque of the output shafts of the two engines to the rotor transmission shaft on the main shaft in a vertical direction.

[0013] As a further technical solution of the present invention: the frame module includes a landing gear and a fuselage load-bearing frame, the fuselage load-bearing frame is fixed above the landing gear, and the landing gear and the fuselage load-bearing frame are both arranged in a left-right symmetrical manner to ensure that the center of gravity of the coaxial twin-rotor unmanned helicopter is centered.

[0014] As a further technical solution of the present invention: the engine module further comprises two radiators and an oil tank, the two radiators are symmetrically installed at the bottom of the two engines with the central axis of the frame module as the reference, and the oil tank is fixed above the fuselage load-bearing frame and connected to the two engines respectively;

[0015] The radiator is used for dissipating heat from the engine, and the fuel tank is used for storing fuel required for the operation of the engine.

[0016] As a further technical solution of the present invention: the two radiators are installed at the top ends of both sides of the fuselage load-bearing frame at an angle of 45°.

[0017] As a further technical solution of the present invention: flexible gaskets are fixed at the bottom of the two engines, and the two engines are detachably fixed to the two ends of the fuselage load-bearing frame through the flexible gaskets and are symmetrically arranged with the central axis of the frame module as a reference.

[0018] As a further technical solution of the present invention: the radiator is composed of an air cooling system and a water cooling system, wherein the air outlet direction of the air cooling system is consistent with the airflow generated when the rotor module moves.

[0019] As a further technical solution of the present invention: the main shaft comprises an upper rotor transmission shaft and a lower rotor transmission shaft which are coaxially arranged, and the upper rotor transmission shaft is a long axis which is assembled inside the lower rotor transmission shaft through a bearing;

[0020] The upper rotor is connected to the upper rotor transmission shaft for forward rotation, and the lower rotor is connected to the lower rotor transmission shaft for reverse rotation. The upper rotor transmission shaft and the lower rotor transmission shaft output power through a gear box to achieve reverse synchronous rotation.

[0021] As a further technical solution of the present invention: the upper rotor comprises an upper propeller disc, an upper rotor blade clamp and an upper blade, the upper propeller disc is detachably fixed to the top end of the upper rotor transmission shaft, and the upper blades are movably mounted on the upper propeller disc through the upper rotor blade clamps;

[0022] The lower rotor includes a lower propeller disc, a lower rotor blade clamp and lower blades. The lower propeller disc is detachably fixed to the top end of the lower rotor transmission shaft, and the lower blades are movably mounted on the lower propeller disc through the lower rotor blade clamps.

[0023] As a further technical solution of the present invention: the upper rotor blade clamp and the upper blades are respectively provided in three numbers, and the three upper blades are respectively and evenly spacedly arranged on the circumference of the upper rotor blade clamp;

[0024] The lower rotor blade clamp and the lower blade are respectively provided in three numbers, and the three lower blades are respectively and evenly spaced apart and arranged on the circumference of the lower rotor blade clamp.

[0025] As a further technical solution of the present invention: the rotor attitude control module includes a differential control mechanism and a rudder control mechanism;

[0026] The differential control mechanism is used to achieve equal and synchronous changes in the elevation angles of the upper rotor and the lower rotor, and the rudder control mechanism is used to achieve changes in the elevation angles of each rotor at different positions within the rotation plane.

[0027] As a further technical solution of the present invention: the reduction box module includes a central reduction box and a left reduction box and a right reduction box symmetrically arranged on both sides of the central reduction box, the left reduction box and the right reduction box are respectively connected to the two engines by transmission, and the central reduction box is connected to the main shaft by transmission;

[0028] The output shaft of the left-mounted reduction gearbox and the output shaft of the right-mounted reduction gearbox are both in the horizontal coaxial direction, and the two are symmetrically arranged with the central axis as the reference. The output end of the central reduction gearbox is perpendicular to the output shafts of the left and right reduction gearboxes. This layout can change the rotational torque of the output shaft of the engine in the horizontal direction to the rotor transmission shaft in the vertical direction.

[0029] As a further technical solution of the present invention: the reduction gearbox module also includes a left-positioned flexible connector and a right-positioned flexible connector, the left-positioned reduction gearbox is connected to the central reduction gearbox via the left-positioned flexible connector, and the right-positioned reduction gearbox is connected to the central reduction gearbox via the right-positioned flexible connector.

[0030] In summary, the present invention includes at least one of the following beneficial technical effects:

[0031] 1. The present invention discloses a load-carrying coaxial twin-rotor unmanned helicopter, which adopts a coaxial twin-rotor design in the rotor part, cancels the tail wing, and can synchronously realize the synchronous elevation adjustment of the upper and lower propellers and the posture adjustment of the fuselage through a full differential control mechanism and a rudder control mechanism. The overall power design adopts a symmetrical layout, which optimizes the center of gravity design of the entire unmanned helicopter to the greatest extent. This structure will greatly improve the stability of the unmanned helicopter, and the unmanned helicopter has a load capacity of one ton, a wide range of applications, and fills the gap in domestic load-carrying unmanned aerial vehicles.

[0032] 2. The present invention relates to a large-scale unmanned helicopter with a load-bearing structure. The helicopter adopts a coaxial twin-rotor design, with three propellers on each layer, and two 200-horsepower fuel engines as power devices. The designed maximum load capacity is 1 ton. The whole machine is composed of a frame module, an engine module, a reduction box module, a rotor module, a rotor attitude control module, etc. The present invention adopts a dual-engine design, and the two engines are symmetrically arranged on both sides of the main transmission shaft, and each engine is equipped with an independent heat dissipation system. The engine outputs power to the main shaft through a reduction mechanism, and the main shaft drives the upper and lower layers of propellers to rotate and generate lift. Each layer of propellers has three blades, and the flight control software will intelligently control the steering gear system. The steering gear system receives instructions to control the dual-rotor attitude adjustment mechanism, and finally achieves the purpose of flight attitude control. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0034] Figure 2 for Figure 1 A partial enlarged schematic diagram of part F in the middle

[0035] Figure 3 It is a schematic diagram of the overall structure of the rotor of the present invention.

[0036] Figure 4 for Figure 3 A partial enlarged schematic diagram of part H in the middle.

[0037] Figure 5 It is a cross-sectional view of the rotor main shaft of the present invention.

[0038] Figure 6 for Figure 5A partial enlarged schematic diagram of part I.

[0039] Figure 7 It is a structural diagram of the rotor module of the present invention.

[0040] Figure symbols: A, frame module; A1, landing gear; A2, fuselage load-bearing frame; B, engine module; B1, engine; B1-1, left engine; B1-2, right engine; B2, radiator; B2-1, left radiator; B2-2, right radiator; B3, fuel tank; B4, flexible gasket; C, reduction box module; C1, central reduction box; C2, left reduction box; C3, right reduction box; C4, left flexible connector; C5, right flexible connector; D, rotor module; D1, main shaft; D2, upper rotor; D3, lower rotor; E, rotor attitude control module; E1, upper rotor attitude control mechanism; E2, lower rotor attitude control mechanism; G1, generator coil; G2, starter motor pulley;

[0041] 1. Differential servo; 2. Steering servo; 3. Lower rotor drive shaft; 4. Total differential hinge; 5. Lower active swash plate hinge; 6. Lower active swash plate; 7. Lower driven swash plate; 8. Lower driven swash plate hinge; 9. Swash plate connecting rod; 10. Lower rudder transmission connecting rod; 11. Lower rocker arm control connecting rod; 12. Lower propeller plate; 13. Lower rotor propeller clamp; 14. Lower rotor rocker arm; 15. Lower differential hinge base; 16. Lower differential hinge; 17. Lower differential base; 18. Lower differential dial; 19. Upper active swash plate Hinge; 20, upper active tilting plate; 21, upper driven tilting plate; 22, upper driven tilting plate hinge; 23, upper rocker arm control link; 24, upper rudder transmission link; 25, upper propeller plate; 26, upper rotor propeller clamp; 27, upper rotor rocker arm; 28, upper differential shifter; 29, upper differential base; 30A, upper differential shaft; 30B, lower differential shaft; 31, upper blade; 32, lower blade; 33, upper rotor transmission shaft; 34A, upper differential shaft rack; 34B, lower differential shaft rack; 35, differential shaft gear. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application; obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments, and all other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application without making creative work are within the scope of protection of the present application.

[0043] In the description of the present application, it should be noted that the terms "upper", "lower", "inner", "outer", "top / bottom" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0044] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "set / connected", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0045] Embodiment 1:

[0046] Reference Figure 1 , a load-carrying coaxial twin-rotor unmanned helicopter disclosed in the present invention, comprising: a frame module A; an engine module B, comprising two engines B1, and the two engines B1 are arranged symmetrically on the frame module A; a rotor module D, comprising a main shaft D1 and an upper rotor D2 and a lower rotor D3 installed on the main shaft D1; a rotor attitude control module E, installed on the main shaft D1 and respectively connected to the upper rotor D2 and the lower rotor D3 for controlling the flight attitude of the upper rotor D2 and the lower rotor D3; a reduction box module C, installed between the engine module B and the main shaft D1, and used to change the output shaft rotation torque of the two engines B1 to the rotor transmission shaft on the main shaft D1 in the vertical direction.

[0047] Among them, refer to Figure 1 The frame module A includes a landing gear A1 and a fuselage load-bearing frame A2. The fuselage load-bearing frame A2 is fixed on the top of the landing gear A1. In this embodiment, the fuselage load-bearing frame A2 is fixed on the top of the landing gear A1 by welding. The landing gear A1 and the fuselage load-bearing frame A2 are both arranged in a left-right symmetrical manner to ensure that the center of gravity of the coaxial twin-rotor unmanned helicopter is centered. The landing gear A1 is the base of the helicopter in contact with the ground. It adopts a sled-type design to ensure greater safety during landing. The fuselage load-bearing frame A2 is the mounting chassis of the entire helicopter mechanism. It is composed of 4 horizontal steel pipes and 8 longitudinal steel pipes cross-welded to form a ship-shaped structure. This structure can provide a stable and reliable installation platform for the helicopter.

[0048] The engine module B also includes two radiators B2 and a fuel tank B3. The two radiators B2 are symmetrically installed at the bottom of the two engines B1 based on the central axis of the frame module A. The fuel tank B3 is fixed above the fuselage load-bearing frame A2 and connected to the two engines B1 respectively; the radiator B2 is used to dissipate heat for the engine B1, and the fuel tank B3 is used to store the fuel required for the engine B1 to work. This design adopts a dual-engine B1 design. Each engine B1 can output a maximum of 200 horsepower. The power system can ensure that the take-off weight reaches 1.5 tons. The entire engine module B consists of two left and right engines (B1-1, B1-2), two left and right radiators (B2-1, B2-2), and a fuel tank B3. The left radiator B2-1 is installed below the left engine B1-1. The installation method of the right engine B1-2 and the right radiator B2-2 is the same as the left side. The left and right sides are symmetrically arranged based on the central axis.

[0049] In this embodiment, refer to Figure 1 The engine B1 is symmetrically fixed at both ends of the fuselage load-bearing frame A2 by bolts, the radiator B2 is installed at a 45-degree angle below the two engines B1 and below both ends of the fuselage load-bearing frame A2, and the fuel tank B3 is fixedly installed in the middle of the fuselage load-bearing frame A2.

[0050] Flexible gaskets B4 are fixed to the bottom of the two engines B1. The two engines B1 are detachably fixed to the two ends of the fuselage load-bearing frame A2 through the flexible gaskets B4 and are symmetrically arranged based on the central axis of the frame module A. The use of flexible material gaskets effectively reduces the vibration of the fuselage when the engine B1 is working.

[0051] Reference Figure 1 The two radiators B2 are installed at the top of both sides of the fuselage load-bearing frame A2 at a 45° angle. The radiator B2 consists of an air cooling system and a water cooling system. The air outlet direction of the air cooling system is consistent with the airflow generated when the rotor module D moves. This design can optimize the air cooling effect.

[0052] Reference Figure 2 The reduction gearbox module C includes a central reduction gearbox C1 and a left reduction gearbox C2 and a right reduction gearbox C3 which are symmetrically arranged on both sides of the central reduction gearbox C1. The left reduction gearbox C2 and the right reduction gearbox C3 are respectively connected to the two engines B1 by transmission, and the central reduction gearbox C1 is connected to the main shaft D1 by transmission. The output shaft of the left reduction gearbox C2 and the output shaft of the right reduction gearbox C3 are both in the horizontal coaxial direction, and the two are symmetrically arranged with the central axis as the reference. The output end of the central reduction gearbox C1 is perpendicular to the output shafts of the left and right reduction gearboxes. This layout can change the rotational torque of the output shaft of the engine B1 in the horizontal direction to the rotor transmission shaft in the vertical direction.

[0053] Reference Figure 2The reduction box module C also includes a left flexible connector C4 and a right flexible connector C5. The left reduction box C2 is connected to the central reduction box C1 through the left flexible connector C4, and the right reduction box C3 is connected to the central reduction box C1 through the right flexible connector C5. The left flexible connector C4 and the right flexible connector C5 can effectively reduce the influence of the vibration of the engine B1 on the axial power transmission, and can effectively enhance the stability of the power transmission.

[0054] The output shaft of engine B1 is connected to the left / right reduction gearbox (C2, C3), which will initially reduce the output speed of engine B1 and adjust the torque value to the required range through the reduction gearbox. The central reduction gearbox C1 further adjusts the output speed and torque, and adjusts the power output in the horizontal direction to the vertical rotor drive shaft through the gearbox structure.

[0055] Reference Figure 2 The generator coil G1 is installed on the intermediate transmission shaft of the left reduction box C2 and the center reduction box C1. This structure will provide charging for the helicopter battery system. The starting pulley G2 is installed on the intermediate transmission shaft of the right reduction box C3 and the center reduction box C1. This mechanism provides a driving connection for the auxiliary starting device.

[0056] The left and right engines (B1-1, B1-2) adjust the speed through the left and right reduction gearboxes (C2, C3) and transmit the power to the central gearbox C1. The central gearbox C1 performs secondary speed change and outputs the power to the main shaft D1, so that the upper rotor drive shaft 33 and the lower rotor drive shaft 3 rotate synchronously and at the same speed in opposite directions.

[0057] Reference Figure 3 and Figure 4 The upper rotor D2 is mounted on the upper rotor transmission shaft 33 through the upper paddle disc 25 and the upper rotor paddle clamp 26, and the lower rotor D3 is mounted on the lower rotor transmission shaft 3 through the lower paddle disc 12 and the lower rotor paddle clamp 13. When the upper and lower rotor transmission shafts (33, 3) rotate, they will drive the upper and lower rotors (D2, D3) to rotate synchronously and at the same speed in opposite directions. Because the upper and lower rotors have opposite airfoils, the reverse rotation can provide lift for the helicopter.

[0058] The flight control system can control the upper and lower rotor attitude control mechanisms (E1, E2) through three directional servos 2 to achieve flight attitude adjustment. The two sets of attitude control mechanisms are synchronized and can simultaneously adjust the elevation angle changes of the six blades. The change in the elevation angle will change the size and direction of the lift. Based on this principle, the flight control system can control the flight attitude of the unmanned helicopter through the upper and lower rotor attitude control mechanisms (E1, E2).

[0059] Reference Figure 4The main shaft includes an upper rotor drive shaft 33 and a lower rotor drive shaft 3 which are coaxially arranged. The upper rotor drive shaft 33 and the lower rotor drive shaft 3 are the power output shafts of the rotor assembly and are also the central axis of the entire mechanism. The upper rotor drive shaft 33 is a long axis and is assembled inside the lower rotor drive shaft 3 through a bearing; the upper rotor is connected to the upper rotor drive shaft 33 for forward rotation, and the lower rotor is connected to the lower rotor drive shaft 3 for reverse rotation. The upper rotor drive shaft 33 and the lower rotor drive shaft 3 output power through a gear box to achieve reverse synchronous rotation. In this embodiment, the structure in which the gear box outputs power to enable the upper rotor drive shaft 33 and the lower rotor drive shaft 3 to rotate reversely and synchronously belongs to the prior art well known to those skilled in the art and will not be described in detail herein.

[0060] Reference Figure 4 The upper rotor includes an upper rotor disc 25, an upper rotor blade clamp 26 and an upper blade 31. The upper rotor disc 25 is detachably fixed to the top of the upper rotor transmission shaft 33, and the upper blades 31 are movably mounted on the upper rotor disc 25 through the upper rotor blade clamp 26; the lower rotor includes a lower rotor disc 12, a lower rotor blade clamp 13 and a lower blade 32. The lower rotor disc 12 is detachably fixed to the top of the lower rotor transmission shaft 3, and the lower blades 32 are movably mounted on the lower rotor disc 12 through the lower rotor blade clamp 13. In this embodiment, the upper rotor disc 25 is fixed to the upper rotor transmission shaft 33 through a spline, and the lower rotor disc 12 is fixed to the lower rotor transmission shaft 3 through a spline.

[0061] In this embodiment, the upper rotor blade clamp 26 and the lower rotor blade clamp 13 are respectively fixed to the upper rotor disc 25 and the lower rotor disc 12 in an axially movable connection manner, and the rotating part uses bearings to ensure its flexibility. The upper blade 31 and the lower blade 32 are respectively fixed to the upper rotor blade clamp 26 and the lower rotor blade clamp 13 with bolts.

[0062] In this embodiment, refer to Figure 7 The upper rotor blade clamp 26 and the upper blade 31 are respectively set to three, and the three upper blades 31 are respectively evenly spaced around the upper rotor blade clamp 26; the lower rotor blade clamp 13 and the lower blade 32 are respectively set to three, and the three lower blades 32 are respectively evenly spaced around the lower rotor blade clamp 13.

[0063] The rotor attitude control module E includes a differential control mechanism and a rudder control mechanism; the differential control mechanism is used to achieve equal and synchronous changes in the elevation angles of the upper rotor D2 and the lower rotor D3, and the rudder control mechanism is used to achieve changes in the elevation angles of each rotor at different positions within the rotating plane.

[0064] Reference Figure 5 and Figure 6The differential control mechanism includes an upper differential shaft 30A, an upper differential shaft rack 34A, a differential shaft gear 35, a lower differential shaft 30B and a lower differential shaft rack 34B. The two sides of the differential shaft gear 35 are respectively meshed with the upper differential shaft rack 34A and the lower differential shaft rack 34B; the upper rotor transmission shaft 33 is a hollow shaft, and the upper differential shaft 30A, the upper differential shaft rack 34A, the differential shaft gear 35, the lower differential shaft 30B and the lower differential shaft rack 34B are assembled inside the upper rotor transmission shaft 33; the top of the upper differential shaft rack 34A is connected to the upper differential shaft 30A, and the bottom of the lower differential shaft rack 34B is connected to the lower differential shaft 30B. Sliding sleeves are installed between the upper rotor transmission shaft 33 and the upper differential shaft 30A and the lower differential shaft 30B, respectively, and the upper differential shaft 30A and the lower differential shaft 30B move in opposite directions.

[0065] The upper differential shaft 30A and the lower differential shaft 30B can realize opposite linear motion through the upper differential shaft rack 34A, the lower differential shaft rack 34B and the differential shaft gear 35, that is, when the lower differential shaft 30B moves upward, the upper differential shaft 30A moves downward, and vice versa.

[0066] Reference Figure 4 The differential control mechanism also includes an upper differential base 29 and a lower differential base 17. The upper differential base 29 is fixed to the top of the upper differential shaft 30A by bolts; the lower differential base 17 is sleeved on the upper rotor transmission shaft 33 through a bearing, and is fixed to the lower differential shaft 30B by bolts through a keyway opened on the upper rotor transmission shaft 33. The bearing structure can realize that the lower differential base 17 can make a linear motion and a rotational motion at the same time with the lower differential shaft 30B.

[0067] Reference Figure 4 The differential control mechanism also includes a differential servo 1, a total differential hinge 4, a lower differential hinge 16, a lower differential hinge base 15, a lower differential shifter 18, a lower rocker arm control link 11, a lower rotor rocker arm 14, an upper differential shifter 28, an upper rocker arm control link 23, and an upper rotor rocker arm 27; the lower differential hinge base 15 is directly fixedly assembled with the lower rotor drive shaft 3 through threads, and is fixed to the lower propeller disc 12 with bolts. This assembly method can ensure that the connection between the lower differential hinge base 15 and the lower rotor drive shaft 3 does not loosen during rotation.

[0068] One end of the lower differential shifter 18 is movably connected to the lower differential base 17, and the other end is movably connected to the lower rocker arm control link 11; one end of the lower rocker arm control link 11 is movably connected to the lower rotor rocker arm 14, and the other end of the lower rotor rocker arm 14 is fixed to the lower rotor blade clamp 13 with bolts; one end of the lower differential hinge 16 is movably connected to the lower differential base 17, and the other end is movably connected to the lower differential hinge base 15;

[0069] One end of the upper differential shifter 28 is movably connected to the upper differential base 29, and the other end is movably connected to the upper rocker arm control link 23; the upper rocker arm control link 23 is movably connected to one end of the upper rotor rocker arm 27, and the other end of the upper rotor rocker arm 27 is fixed to the upper rotor blade clamp 26 with bolts.

[0070] The top end of the telescopic push rod of the differential servo 1 is movably connected to the total differential hinge 4, and the lower differential shaft 30B is fixed to the total differential hinge 4 through a bearing. The total differential hinge 4 is fixed by a limit screw so that the lower differential shaft 30B is driven by the total differential hinge 4 to perform linear motion, and the lower differential shaft 30B is synchronously rotated with the upper rotor transmission shaft 33.

[0071] Differential control mechanism principle description:

[0072] When the flight control system drives the telescopic push rod of the differential servo 1 to make linear motion, the lower differential shaft 30B will be driven to make linear motion in the upper rotor transmission shaft 33, and the direction of the linear motion can be controlled according to the requirements of flight attitude adjustment.

[0073] The lower differential shaft 30B is fixedly connected to the lower differential rack, and the upper differential shaft 30A is fixedly connected to the upper differential rack, and the two racks are engaged with a differential shaft gear 35. When the lower differential shaft 30B makes a linear motion, the upper differential shaft 30A will be driven to make a reverse linear motion through the lower differential rack and the differential shaft gear 35. When the upper differential shaft 30A makes a linear motion, it will drive the upper differential base 29 and the lower differential base 17 to make synchronous linear motion together.

[0074] Because one end of the upper differential shifter 28 is fixed by the upper rudder transmission connecting rod, when the upper differential base 29 performs linear motion, it will drive the upper differential shifter 28 to produce angular displacement, that is, one end is stationary, and the other end performs up and down angular difference motion.

[0075] When the upper differential shifter 28 makes an angular movement, it will drive the upper rocker arm control link 23 to move up and down, and the other end of the upper rocker arm control link 23 is movably connected to the upper rotor rocker arm 27, and this movement will directly drive the upper rotor rocker arm 27 to make an angular change movement.

[0076] One end of the upper rotor rocker arm 27 is fixed to the upper rotor blade clamp 26 by bolts. When the upper rotor rocker arm 27 performs angle change movement, it will directly drive the upper rotor blade clamp 26 to perform synchronous angle change movement, and similarly, it will also drive the upper rotor to change its angle.

[0077] Similarly, when the lower differential shaft 30B performs linear motion, it will drive the lower differential base 17 to perform synchronous linear motion, and drive the lower rocker arm control link 11 to reciprocate up and down through the lower differential shifter 18. The lower differential rocker arm link will drive the lower rotor to perform angle change motion through the lower rotor rocker arm 14. The lower differential hinge 16 plays a fixed support role, which will make the movement of the lower differential shifter 18 more stable.

[0078] The two layers of rotors of the coaxial twin-rotor helicopter rotate in opposite directions at the same speed. Since the airfoil installation directions of the upper and lower rotors are also opposite, the upper and lower rotors can provide lift output for the helicopter when they move in opposite directions. In summary, the flight control system can drive the differential servo 1 to achieve synchronous and unidirectional elevation changes of the upper blade 31 and the lower blade 32 through the differential control mechanism. Since the upper and lower wing shapes are in opposite directions, the synchronous and unidirectional elevation changes can control the complementary changes in the lift of the upper and lower rotors (the lift of one rotor increases, and the lift generated by the other rotor decreases, and vice versa), and the total lift of the helicopter will not change. According to the principle of action and reaction, the reaction force when the two layers of rotors cut through the air will also produce a difference, and this difference will cause the helicopter itself to spin. Based on this principle, the horizontal direction of the fuselage can be adjusted by the differential servo 1, that is, the direction of the fuselage (head direction) can be adjusted arbitrarily.

[0079] Reference Figure 4 The steering control mechanism includes a steering gear 2, a lower active swash plate 6, a lower active swash plate hinge 5, a lower driven swash plate 7, a lower driven swash plate hinge 8, a lower steering transmission link 10, a swash plate link 9, an upper active swash plate 20, and an upper active swash plate hinge 19;

[0080] One end of the lower driven swash plate hinge 8 is movably connected to the lower driven swash plate 7, and the other end is movably connected to the lower rotor transmission shaft 3; one end of the upper active swash plate hinge 19 is movably connected to the upper active swash plate 20, and the other end is movably connected to the lower rotor transmission shaft 3; the telescopic push rod of the steering gear 2 is movably connected to the lower active swash plate 6, and when the steering gear 2 moves, it drives the lower active swash plate 6 to produce an angle change in the vertical direction of the lower rotor transmission shaft 3.

[0081] The lower active swash plate 6 and the lower driven swash plate 7 are fixed on the lower rotor transmission shaft 3 through articulated bearings. The lower active swash plate 6 is fixed and does not rotate through the bearing structure, and the lower driven swash plate 7 rotates synchronously with the lower rotor transmission shaft 3, and both swash plate surfaces can make a certain angle of synchronous deflection in the vertical direction of the lower rotor transmission shaft 3; one end of the lower active swash plate hinge 5 is fixed to the reduction gearbox sleeve by bolts, and the other end is movably connected to the lower active swash plate 6. The lower active swash plate hinge 5 mainly plays a role in stabilizing the posture of the lower active swash plate 6.

[0082] The lower driven swash plate 7 is bidirectionally movably connected to the upper active swash plate 20 through the swash plate connecting rod 9. When the lower driven swash plate 7 is angularly offset, the upper active swash plate 20 can be synchronously driven to make synchronous posture adjustment through the swash plate connecting rod 9, and the angle tilting direction and the angle change value are consistent. The lower driven swash plate 7 is bidirectionally movably connected to the lower differential shifter 18 through the lower steering transmission connecting rod 10. When the lower driven swash plate 7 is angularly offset, the lower steering transmission connecting rod 10 can be synchronously driven to make synchronous posture adjustment through the lower steering transmission connecting rod 10, and the angle tilting direction and the angle change value are consistent.

[0083] The lower differential shifter 18 is bidirectionally movably connected to the lower rotor rocker arm 14 through the lower rocker arm control link 11. The lower rotor rocker arm 14 is installed on the lower rotor blade clamp 13. The attitude adjustment of the lower differential shifter 18 can drive the lower rotor blade clamp 13 to change the elevation angle through the lower rocker arm control link 11 and the lower rotor rocker arm 14.

[0084] The steering control mechanism also includes an upper driven swash plate 21, an upper driven swash plate hinge 22, and an upper steering transmission link 24; the upper active swash plate 20 and the upper driven swash plate 21 are fixed to the upper rotor transmission shaft 33 through a joint bearing, and the upper active swash plate 20 can rotate synchronously with the lower driven swash plate 7 through the bearing structure, and the upper driven swash plate 21 can rotate synchronously with the upper rotor transmission shaft 33, and both swash plate surfaces can make a certain angle of synchronous deflection in the vertical direction of the upper rotor transmission shaft 33, and the two swash plates have the same rotation speed but opposite directions.

[0085] The upper driven swash plate 21 and the upper differential shifter 28 are bidirectionally movably connected through the upper steering transmission link 24. When the upper driven swash plate 21 makes an angular deviation, the upper differential shifter 28 can be synchronously driven by the upper steering transmission link 24 to make a synchronous attitude adjustment, and the angular tilt direction and the angle change value are consistent.

[0086] One end of the hinge of the upper driven swash plate 21 is fixed to the upper rotor transmission shaft 33 by bolts, and the other end is movably connected to the upper driven swash plate 21 . The hinge of the upper driven swash plate 21 mainly serves to stabilize the posture of the upper driven swash plate 21 .

[0087] The upper differential shifter 28 is bidirectionally movably connected to the upper rotor rocker arm 27 through the upper rocker arm control link 23. The upper rotor rocker arm 27 is installed on the upper rotor blade clamp 26. The attitude adjustment of the upper differential shifter 28 can drive the upper rotor blade clamp 26 to change the elevation angle through the upper rocker arm control link 23 and the upper rotor rocker arm 27.

[0088] In this embodiment, three steering gears 2 are provided, and the telescopic push rods of the three steering gears 2 are movably connected to the three connecting arms of the lower driven swash plate 7 respectively, and the connection points are spaced at an angle of 120 degrees.

[0089] Furthermore, in the present embodiment, the number of the swash plate link 9, the lower rudder transmission link 10, the lower rocker arm control link 11, the lower rotor blade clamp 13, the lower rotor rocker arm 14, the lower differential hinge 16, the lower differential shifter 18, the upper rocker arm control link 23, the upper rudder transmission link 24, the upper rotor blade clamp 26, the upper rotor rocker arm 27, and the upper differential shifter 28 are all set to three, and the movable connection in the present embodiment is preferably a hinged connection.

[0090] Rudder control mechanism principle description:

[0091] The purpose of rudder control is to achieve directional adjustment of the helicopter during flight. The flight control system controls the rudder 2 to push the lower active swash plate 6, the lower driven swash plate 7, the upper active swash plate 20, and the upper driven swash plate 21 to adjust the angle. The attitude changes of the four swash plates are synchronous. The driven swash plate ultimately drives the propeller to adjust the pitch angle through the connecting rod and the rocker arm. Unlike differential control, rudder control does not synchronously and equally adjust the pitch angles of the six rotors. It uses the inclination angle of the swash plate to achieve continuous pitch angle changes at different positions of the rotor during rotation. The pitch angle of each position is complementary to the position on the other side of the central axis.

[0092] For example, if the rotor is adjusted by plus 3 degrees when passing a certain point, then the rotor will be adjusted by minus 3 degrees when passing the other side of the symmetry. The entire elevation angle changes continuously and periodically every circle, and the changes of the upper and lower double-layer rotors are also synchronized. The rudder control mechanism can realize the continuous change of the elevation angle of the two layers of rotors, and this periodic and continuous change will cause each layer of rotors to generate lift that is inconsistent with the direction of the central axis during movement (when the rotor elevation angle is continuously fixed, the lift is vertically upward. When the rotor has an elevation angle difference at a symmetrical position, the lift direction will form an angle with the central axis, that is, a lateral thrust will be generated). This lift will push the aircraft to move horizontally in this direction.

[0093] Rudder control is based on this principle. The flight control system can be used to drive the steering servo 2 to adjust the tilt angle of the swash plate, so that the swash plate drives the rotor to make periodic pitch changes. The change in lift direction drives the helicopter to move horizontally. The direction of the horizontal movement of the aircraft is consistent with the direction of the ray from the highest point of the swash plate to the lowest point of the swash plate.

[0094] In short, refer to Figure 1 and Figure 4, Rotor attitude control module E: This module consists of an upper rotor attitude control mechanism E1 and a lower rotor attitude control mechanism E2. The two sets of control mechanisms are executed synchronously, and can simultaneously control the six rotors in the upper and lower layers to achieve pitch changes. The three directional servos 2 are connected to the lower active swash plate 6, and the tilt attitude of the lower active swash plate 6 in any direction within 15 degrees can be controlled by the differential servo 1. The lower active swash plate 6 can drive the upper active swash plate 20 to make synchronous attitude changes through the active connection with the lower driven swash plate 7 and the swash plate connecting rod 9.

[0095] Reference Figure 4 The lower driven swash plate 7 is movably connected with the lower differential shifter 18 through the lower rudder direction transmission link 10, and the lower rotor rocker arm 14 is movably connected with the lower differential shifter 18 through the lower rocker arm control link 11. When the tilt angle of the lower driven swash plate 7 changes, the lower differential shifter 18 can be driven by the lower rudder direction transmission link 10 to make a synchronous attitude change, and the lower differential shifter 18 drives the lower rotor rocker arm 14 to make a corresponding attitude change through the lower rocker arm control link 11. Finally, the lower rotor rocker arm 14 drives the lower rotor D4 to make a corresponding elevation angle change.

[0096] Reference Figure 4 Similarly, the upper driven swash plate 21 is movably connected to the upper differential shifter 28 through the upper rudder direction transmission link 24, and the upper rotor rocker arm 27 is movably connected to the upper differential shifter 28 through the upper rocker arm control link 23. When the upper driven swash plate 21 produces a tilt angle change, the upper differential shifter 28 can be driven by the upper rudder direction transmission link 24 to make a synchronous attitude change, and the upper differential shifter 28 drives the upper rotor rocker arm 27 to make a corresponding attitude change through the upper rocker arm control link 23. Finally, the upper rotor rocker arm 27 will drive the upper rotor D3 to make a corresponding elevation angle change.

[0097] The rotor assembly system of the coaxial twin-rotor of the present invention mainly includes two parts: a rotor structure and a rotor attitude control system, and its purpose is to achieve linkage control of the two layers of six blades of the helicopter with this structure, so that the helicopter maintains an optimal flight attitude.

[0098] The attitude control system can be specifically divided into differential control and rudder control. Differential control can achieve equal and synchronous changes in the pitch angles of the upper and lower layers of blades. Since the rotation speed of the two layers of blades is always the same, different pitch angles will produce different reaction forces when the two layers of blades cut through the air. The difference in the force will cause the fuselage to spin. Based on this principle, the differential control system can enable the helicopter to freely adjust the horizontal direction of the fuselage (control the horizontal position of the nose) without a tail.

[0099] The rudder control can achieve the change of the elevation angle of each layer of blades at different positions in the rotating surface (with the main axis as the center of the circle, and the rotating surface of each layer of blades as a circle, the rudder control system can control the elevation angle of the two layers of blades to achieve continuous change during the rotation process, that is, the elevation angle of all blades is fixed when passing a fixed position during rotation, and the elevation angle change is positive and negative and complementary in the direction of symmetry with the center of the circle. If the angle change at a certain position is positive N degrees, the elevation angle change at the symmetric position with the center of the circle is negative N degrees), and the change direction and amount of the upper and lower layers of blades are consistent. This control can make the elevation angle of the two layers of blades produce a fixed difference in any two directions symmetrical with the center of the circle. This elevation angle difference will cause the helicopter to generate lift inconsistent with the main axis direction. Based on this principle, the rudder control can adjust the elevation angle change to achieve the movement of the helicopter in any horizontal direction (that is, to achieve the lateral movement of the helicopter in any direction). The flight control system can synchronously adjust the two sets of control mechanisms to achieve synchronous elevation control of the double-layer six blades, greatly enhancing the controllability and stability of the helicopter.

[0100] The present invention can be called full differential fuselage attitude adjustment, which can realize synchronous pitch adjustment of the upper and lower propellers, and the total lift of the aircraft remains unchanged when the fuselage direction is adjusted. The two attitude adjustment systems share a rocker control system at the end, which not only simplifies the structure and enhances stability, but also reduces the control difficulty. The application of this system on coaxial twin-rotor helicopters not only enhances the helicopter's attitude adjustment capability, but also greatly improves the flight attitude stability, while also reducing the control difficulty.

[0101] The implementation principle of the present invention is as follows: the present invention discloses a load-bearing coaxial twin-rotor unmanned helicopter, which adopts a coaxial twin-rotor design in the rotor part, cancels the tail wing, and can synchronously realize the synchronous elevation adjustment of the upper and lower layers of propellers and the adjustment of the fuselage attitude through a full differential control mechanism and a rudder control mechanism. The overall power design adopts a symmetrical layout, which optimizes the center of gravity design of the entire unmanned helicopter to the greatest extent. This structure will greatly improve the stability of the unmanned helicopter, and the unmanned helicopter has a load capacity of one ton, a wide range of applications, and fills the gap in domestic load-bearing unmanned aerial vehicles.

[0102] The embodiments of this specific implementation method are all preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A load-carrying coaxial twin-rotor unmanned helicopter, characterized in that: include: Framework module (A); The engine module (B) comprises two engines (B1), wherein the two engines (B1) are arranged symmetrically on the frame module (A); A rotor module (D), comprising a main shaft (D1) and an upper rotor (D2) and a lower rotor (D3) mounted on the main shaft (D1); a rotor attitude control module (E), mounted on the main shaft (D1) and respectively connected in transmission with the upper rotor (D2) and the lower rotor (D3), and used for controlling the flight attitude of the upper rotor (D2) and the lower rotor (D3); The reduction box module (C) is installed between the engine module (B) and the main shaft (D1) and is used to change the rotational torque of the output shafts of the two engines (B1) to the rotor transmission shaft on the main shaft (D1) in a vertical direction.

2. The load-carrying coaxial twin-rotor unmanned helicopter according to claim 1, characterized in that: The frame module (A) comprises a landing gear (A1) and a fuselage load-bearing frame (A2), wherein the fuselage load-bearing frame (A2) is fixed above the landing gear (A1), and the landing gear (A1) and the fuselage load-bearing frame (A2) are both arranged in a left-right symmetrical manner to ensure that the center of gravity of the coaxial twin-rotor unmanned helicopter is centered.

3. The load-carrying coaxial twin-rotor unmanned helicopter according to claim 2, characterized in that: The engine module (B) further comprises two radiators (B2) and a fuel tank (B3), wherein the two radiators (B2) are symmetrically mounted on the bottom of the two engines (B1) with the central axis of the frame module (A) as a reference, and the fuel tank (B3) is fixed above the fuselage load-bearing frame (A2) and is connected to the two engines (B1) respectively; The radiator (B2) is used for dissipating heat from the engine (B1), and the fuel tank (B3) is used for storing fuel required for the operation of the engine (B1).

4. The load-carrying coaxial twin-rotor unmanned helicopter according to claim 3, characterized in that: The two radiators (B2) are both installed at the top ends of both sides of the fuselage load-bearing frame (A2) at an inclination angle of 45°.

5. The load-carrying coaxial twin-rotor unmanned helicopter according to claim 3, characterized in that: A flexible gasket (B4) is fixed at the bottom of the two engines (B1), and the two engines (B1) are detachably fixed to the two ends of the fuselage load-bearing frame (A2) through the flexible gasket (B4) and are symmetrically arranged with the central axis of the frame module (A) as a reference.

6. A load-carrying coaxial twin-rotor unmanned helicopter according to any one of claims 1 to 5, characterized in that: The radiator (B2) is composed of an air cooling system and a water cooling system, wherein the air outlet direction of the air cooling system is consistent with the airflow generated when the rotor module (D) moves.

7. The load-carrying coaxial twin-rotor unmanned helicopter according to claim 1, characterized in that: The main shaft (D1) comprises an upper rotor transmission shaft (33) and a lower rotor transmission shaft (3) which are coaxially arranged, wherein the upper rotor transmission shaft (33) is a long axis which is assembled inside the lower rotor transmission shaft (3) through a bearing; The upper rotor (D2) is connected to the upper rotor transmission shaft (33) for forward rotation, and the lower rotor (D3) is connected to the lower rotor transmission shaft (3) for reverse rotation. The upper rotor transmission shaft (33) and the lower rotor transmission shaft (3) output power through a gear box to achieve reverse synchronous rotation.

8. The load-carrying coaxial twin-rotor unmanned helicopter according to claim 7, characterized in that: The upper rotor (D2) comprises an upper propeller disc (25), an upper rotor propeller clamp (26) and upper propeller blades (31), wherein the upper propeller disc (25) is detachably fixed to the top end of the upper rotor transmission shaft (33), and the upper propeller blades (31) are movably mounted on the upper propeller disc (25) through the upper rotor propeller clamp (26); The lower rotor (D3) comprises a lower propeller disc (12), a lower rotor blade clamp (13) and lower blades (32); the lower propeller disc (12) is detachably fixed to the top end of the lower rotor transmission shaft (3); and the lower blades (32) are movably mounted on the lower propeller disc (12) through the lower rotor blade clamp (13).

9. The load-carrying coaxial twin-rotor unmanned helicopter according to claim 8, characterized in that: The upper rotor blade clamp (26) and the upper blades (31) are respectively provided in number of three, and the three upper blades (31) are respectively evenly spaced and arranged on the circumference of the upper rotor blade clamp (26); The lower rotor blade clamp (13) and the lower blade (32) are respectively arranged in three numbers, and the three lower blades (32) are respectively arranged at even intervals on the circumference of the lower rotor blade clamp (13).

10. The load-carrying coaxial twin-rotor unmanned helicopter according to claim 1, characterized in that: The rotor attitude control module (E) includes a differential control mechanism and a rudder control mechanism; The differential control mechanism is used to achieve equal and synchronous changes in the elevation angles of the upper rotor (D2) and the lower rotor (D3), and the rudder control mechanism is used to achieve changes in the elevation angles of each rotor at different positions within the rotation plane.

11. The load-carrying coaxial twin-rotor unmanned helicopter according to claim 1, characterized in that: The reduction gearbox module (C) comprises a central reduction gearbox (C1) and a left reduction gearbox (C2) and a right reduction gearbox (C3) symmetrically arranged on both sides of the central reduction gearbox (C1), the left reduction gearbox (C2) and the right reduction gearbox (C3) are respectively connected to the two engines (B1) in a transmission manner, and the central reduction gearbox (C1) is connected to the main shaft (D1) in a transmission manner; The output shaft of the left-mounted reduction gearbox (C2) and the output shaft of the right-mounted reduction gearbox (C3) are both in the horizontal coaxial direction, and the two are symmetrically arranged with the central axis as the reference. The output end of the central reduction gearbox (C1) is perpendicular to the output shafts of the left and right reduction gearboxes. This layout can change the rotational torque of the output shaft of the engine (B1) in the horizontal direction to the rotor transmission shaft in the vertical direction.

12. The load-carrying coaxial twin-rotor unmanned helicopter according to claim 11, characterized in that: The reduction gearbox module (C) further comprises a left-positioned flexible connector (C4) and a right-positioned flexible connector (C5); the left-positioned reduction gearbox (C2) is connected to the central reduction gearbox (C1) via the left-positioned flexible connector (C4); and the right-positioned reduction gearbox (C3) is connected to the central reduction gearbox (C1) via the right-positioned flexible connector (C5).

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