Engine-following multi-mode composite high-speed helicopter

Abstract

This invention proposes a multi-mode composite high-speed helicopter with an engine that follows rotation, belonging to the field of helicopter technology. It includes a fuselage, rotor, power system, transmission system, and a propeller. In the power system, the engine retains only rotational freedom around its output shaft from the fuselage, isolating torque transmission between the engine and fuselage. The reverse torque generated by the rotor's rotation and interaction with the air is transmitted through the transmission system, driving only the engine to rotate in the opposite direction, without being transmitted to the fuselage, eliminating the need for a tail rotor to balance torque. A lift fan is coaxially fixed to the engine along its output shaft. The lift fan generates additional lift by rotating synchronously in the opposite direction to the engine. The reverse torque generated by the rotor, engine, and lift fan assembly rotating in opposite directions and acting on the air is balanced. A tilting mechanism is installed on the fuselage, enabling switching between helicopter and autogyro modes with the assistance of the transmission system. This invention achieves high-speed helicopter flight while effectively improving reliability, economy, safety, and service life.

Description

Technical Field

[0001] This invention relates to the field of helicopter technology, and more specifically to a high-speed helicopter with an engine that follows rotation and operates in multiple modes. Background Technology

[0002] Traditional helicopters rely on the high-speed rotation of their rotors for forward flight and hovering. The faster the helicopter flies, the faster the rotor speed. At high-speed level flight, the advancing blade approaches the speed of sound, while the retreating blade experiences a backflow zone, resulting in reduced rotor lift and a surge in drag and power demand. Considering constraints such as material structure strength, economy, and range, the maximum cruising speed of conventional helicopter configurations is typically around 300 km / h. Because helicopters can take off and land vertically and hover freely, they play an irreplaceable role in rapid force projection, disaster relief and search and rescue, and close air support in highly competitive environments. Increasing the cruising speed of helicopters allows them to firmly grasp the battlefield principle of speed being paramount.

[0003] Helicopters with a maximum cruising speed exceeding 300 km / h can be called high-speed helicopters. Based on the known configuration characteristics, technical features, flight and control principles of high-speed helicopters, existing high-speed helicopters can be divided into: compound helicopters, tilt-rotor helicopters, and stationary helicopters.

[0004] Compound high-speed helicopters are helicopters based on traditional single-rotor or coaxial twin-rotor helicopters, with the addition of fixed wings and horizontal propulsion. Takeoff, hovering, and landing are accomplished by the lift generated by the rotor, while the thrust required for forward flight is mainly generated by the horizontal propulsion. Single-rotor compound high-speed helicopters require an additional turbojet engine, resulting in a significant increase in weight, cost, and fuel consumption. Furthermore, because they retain a tail rotor to balance counter-rotating torque, their energy efficiency, reliability, and economic performance are relatively low. Additionally, due to the safety risks of tail rotor failure or loss of control after a tail rotor is hit in battle, they have not been mass-produced and deployed beyond prototype manufacturing. Coaxial twin-rotor compound high-speed helicopters utilize two coaxial counter-rotating rotors, eliminating the need for a tail rotor to balance counter-rotating torque, thus improving engine energy efficiency. However, the additional engine still significantly increases the helicopter's weight, cost, and fuel consumption. To reduce drag caused by the excessive length of traditional twin rotor shafts and avoid collisions during rotation, the "leading blade concept" is currently widely adopted. This is based on a coaxial, rigidly counter-rotating rotor system design, which demands high rotor stiffness. Under multiple constraints related to weight, size, strength, and stiffness, the rotor design is challenging and expensive. The torque transmitted to the hub by a rigid rotor is much greater than that of a traditional hinged rotor. Because the upper and lower rotors are coaxial and counter-rotating, this torque is effectively doubled, significantly increasing the difficulty of designing a hub structure and weight to withstand such a large torque. Furthermore, coaxial twin rotors require more complex control systems, and the active vibration control system used to reduce the significant vibrations present in this new helicopter configuration further increases the empty weight ratio of this type of helicopter.

[0005] Tiltrotor high-speed helicopters utilize symmetrically mounted rotor tilting systems at both ends of the wings of a fixed-wing aircraft. These systems can rotate between horizontal and vertical positions. During vertical takeoff and landing, the rotor shaft is perpendicular to the ground, resulting in a tandem helicopter flight configuration, allowing for hovering, forward / backward flight, and lateral flight. In level flight, the rotor shaft is parallel to the ground, and the rotors transform into large propellers, generating propulsion. Key examples include the V-22 Osprey and V-280, all capable of reaching speeds exceeding 460 km / h. Tiltrotor high-speed helicopters combine the characteristics of helicopters and fixed-wing propellers, exhibiting a "crossover" feature. While they offer advantages such as low vibration and noise, their near-ground maneuverability is lower than that of hybrid helicopters. The rotor tilting system significantly increases the complexity of the structure, control system, and power system, leading to substantial cost increases and reduced reliability.

[0006] A stationary high-speed helicopter achieves both low- and high-speed flight by controlling the operation of aerodynamic components in both states. Specifically, in low-speed states, the rotor rotates to provide aerodynamic force, while in high-speed states, the rotor blades are stationary or retracted (like a disc rotorcraft), providing aerodynamic force in a fixed-wing manner. Key examples include the US X-50A "Dragonfly" and the "X-Wing" project. Stationary helicopters are a relatively new type of high-speed helicopter, combining the characteristics of a helicopter with the ability to achieve even higher speeds through jet engines. The disadvantages include lower aerodynamic efficiency due to the rotor system needing to operate in both rotating and fixed / retracted states, and the need for high rigidity and strength to support the entire aircraft's load when transitioning to a fixed-wing configuration. This undoubtedly increases the structural weight of the rotor significantly, and the flight control system becomes more complex. Furthermore, some core technologies have not yet achieved substantial breakthroughs.

[0007] In summary, although the flight speed of various high-speed helicopters currently known has been greatly improved compared to traditional helicopters, they mostly adopt additional power systems, special material rotors, and complex structural and control system designs. This results in increased weight and cost, as well as reduced lifespan, safety, and range. As a result, except for a few models such as the V-22, most other high-speed helicopters are still in the testing and experimental stage and have not yet been mass-produced.

[0008] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the present invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0009] To address the technical problems existing in the prior art, the present invention provides an engine-driven multi-mode composite high-speed helicopter.

[0010] A multi-mode compound high-speed helicopter with an engine that follows rotation includes a fuselage, a rotor, a power system, a transmission system, and a propeller; the power system includes an air intake, a power nacelle, an engine, a lift fan, and louvered rudders; the transmission system includes an output shaft, a main gear, a drive shaft, a driven gear, a rotor shaft, a universal joint, a propeller shaft, a horizontal clutch, and a vertical clutch; the rotor includes a hub and at least two rotor blades mounted on the hub.

[0011] The fuselage is the structure that carries the equipment on the aircraft and maintains the aerodynamic shape required for flight. It includes two fixed wings that are symmetrically located on both sides of the middle, a horizontal tail, elevator, vertical tail and rudder located at the tail, landing gear located at the bottom, and a tilting mechanism located at the top.

[0012] The engine compartment is fixedly installed at the bottom of the fuselage and has an air intake and an exhaust port. The air intake is connected to the air intake duct, and the air intake opening faces the nose of the fuselage. The engine and the lift fan are coaxially connected in series and installed in the engine compartment along the output shaft. Only one degree of freedom of rotation of the engine around the output shaft is retained between the engine and the engine compartment, which isolates the torsional torque transmission path between the engine and the fuselage. The engine is balancing and rotates freely and synchronously with the lift fan around the output shaft.

[0013] The louvered rudder consists of four sets of rudders located at the exhaust port of the engine compartment, dividing the exhaust port into four sectors. Each set of rudders independently controls the deflection direction. By deflecting in the same direction or differentially, the airflow direction of the exhaust port is changed, which is used to control the high-speed helicopter to pitch, yaw, and roll.

[0014] The output shaft is fixedly connected to the engine power output end. A main gear is mounted on the output shaft. The transmission shaft is perpendicular to the output shaft. A driven gear is mounted on the transmission shaft. The output shaft and the transmission shaft transmit power through the meshing of the main gear and the driven gear. The transmission shaft is coaxially connected to the propeller shaft through a horizontal clutch. The other end of the propeller shaft is fixedly connected to the propeller. The output shaft is coaxially connected to the rotor shaft through a vertical clutch. The rotor shaft is fixedly connected to the rotor hub through a universal joint. The universal joint passes radially through the tilting mechanism.

[0015] A horizontal clutch is used to disconnect or close the power transmission between the drive shaft and the propeller shaft, while a vertical clutch is used to disconnect or close the power transmission between the output shaft and the rotor shaft.

[0016] The rotor and lift fan rotate in opposite directions around the output shaft. The blade structure is designed to push the airflow around them downward to obtain upward lift. The propeller blade structure is designed to push the surrounding air backward when rotating under the drive of the power system and transmission system to obtain forward reaction force.

[0017] Furthermore, the tilt mechanism rotates around the pitch direction of the fuselage, causing the universal joint passing through it to rotate as well, changing the orientation of the universal joint shaft, so that the normal to the rotor's plane of rotation is in two different states: vertical and backward tilt. This, combined with the engagement / disengagement of the vertical clutch, enables the switching between helicopter and autogyro modes.

[0018] Furthermore, the engine drives the rotor to rotate at high speed through the transmission system to generate lift. The reverse torque generated by the rotor interacting with the air is transmitted through the transmission system to drive the engine and the lift fan fixed to it to rotate in the opposite direction to generate additional lift. The reverse torque generated by the rotor, engine and lift fan assembly rotating in the opposite direction and acting on the air is balanced by each other.

[0019] Furthermore, the engine also includes a reduction gear mechanism.

[0020] Furthermore, the engine is either a piston engine or a turboshaft engine.

[0021] Furthermore, the main gear and driven gear are helical bevel gears, straight bevel gears, or curved bevel gears.

[0022] The beneficial technical effects achieved by this invention are:

[0023] The engine-driven multi-mode composite high-speed helicopter solution features a simple structure, power, and control system design, high safety and reliability, high technological maturity, and relatively low cost. It has the ability to freely switch between different flight states such as helicopter and autogyro, and offers multiple selectable modes such as high-speed flight and medium-to-low-speed cruise. It combines the advantages of most known high-speed helicopters while effectively avoiding their prominent shortcomings and deficiencies, demonstrating outstanding substantive features and significant progress.

[0024] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings. Attached Figure Description

[0025] Figure 1 This is a front view of one specific embodiment of the present invention;

[0026] Figure 2 yes Figure 1 The left view;

[0027] Figure 3 yes Figure 1 The bottom view;

[0028] Figure 4 yes Figure 1 Top view;

[0029] Figure 5 yes Figure 1 Axonometric view;

[0030] Figure 6 This is a left rear half sectional top view of the power compartment in an uncut state according to one specific embodiment of the present invention;

[0031] Figure 7 This is a top view of the left rear half of the engine compartment in a cut-open state according to one specific embodiment of the present invention;

[0032] Figure 8 This is a partially enlarged left sectional view of the power compartment and transmission system according to one specific embodiment of the present invention;

[0033] Figure 9 This is a top-section view of the left half of the power compartment according to one specific embodiment of the present invention;

[0034] Figure 10 This is a partially enlarged top view of the power compartment according to one specific embodiment of the present invention;

[0035] Figure 11 This is a partially enlarged side view of the tilting mechanism and rotor shaft according to one specific embodiment of the present invention;

[0036] Figure 12 This is a left-side view of the autorotor in flight state according to one specific embodiment of the present invention.

[0037] Reference numerals: 1. Fuselage; 11. Fixed wing; 12. Horizontal tail; 13. Elevator; 14. Vertical tail; 15. Rudder; 16. Landing gear; 17. Tilting mechanism; 2. Rotor; 21. Wing hub; 22. Rotor blade; 3. Power system; 31. Air intake; 32. Power nacelle; 33. Engine; 34. Lift fan; 35. Loudsaw rudder; 4. Propeller; 5. Transmission system; 51. Output shaft; 511. Main gear; 52. Drive shaft; 521. Driven gear; 53. Rotor shaft; 531. Universal joint; 54. Propeller shaft; 55. Horizontal clutch; 56. Vertical clutch. Detailed Implementation

[0038] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Specific details such as particular system structures, models, and technical parameters mentioned in the following description are merely illustrative of the specific embodiments and not intended to limit the scope of protection of the present invention. Furthermore, content that should be known and understood by those skilled in the art will not be repeated here.

[0039] Furthermore, in the description of this invention, the terms "upper," "lower," "left," "right," "front," "back," "upper left," and "upper right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only used for the convenience of describing this invention and do not require that this invention be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0040] like Figures 1-12 As shown, a specific embodiment of an engine-driven multi-mode composite high-speed helicopter adopts a single-rotor, tailless design and includes a fuselage 1, a rotor 2, a power system 3, a propeller 4, and a transmission system 5.

[0041] The fuselage 1 is a structure that carries the equipment on board and maintains the aerodynamic shape required for flight, including fixed wings 11, horizontal tail 12, elevator 13, vertical tail 14, rudder 15, landing gear 16, and tilt mechanism 17.

[0042] In this specific embodiment, the fuselage 1 adopts a symmetrical structure. There are two fixed wings 11, which are symmetrically arranged on both sides of the middle part of the fuselage 1. They are mainly used to generate lift and also generate drag to suppress the roll motion of the fuselage 1 around the longitudinal axis.

[0043] One horizontal tail 12 and one vertical tail 14 are each located at the rear of the fuselage 1. In this specific embodiment, there are two vertical tail 14s, symmetrically arranged at both ends of the horizontal tail 12. There are two sets of elevators 13, symmetrically arranged on the horizontal tail 12. There are two sets of rudders 15, symmetrically arranged on the vertical tail 14. There is one set of landing gear 16, symmetrically arranged at the bottom of the fuselage 1. In this specific embodiment, the landing gear 16 is a wheeled landing gear, but a tricycle landing gear or a skid landing gear can also be used. The tilting mechanism 17 is located at the top of the fuselage 1 and is used to control the tilting of the rotor 2.

[0044] The rotor 2 includes a hub 21 and rotor blades 22. In this specific embodiment, there are four rotor blades 22 mounted on the hub 21. However, three, five or other numbers can be used depending on actual needs.

[0045] The power system 3 includes an air intake 31, a power nacelle 32, an engine 33, a lift fan 34, and a louvered rudder 35. The power nacelle 32 is fixedly installed at the bottom of the fuselage 1 and has an air intake and an exhaust port. The air intake is connected to the air intake 31, with the opening of the air intake 31 facing the nose of the fuselage 1. The louvered rudder 35 is located at the exhaust port of the power nacelle 32. The engine 33 and the lift fan 34 are located below the rotor 2 and are coaxially connected in series within the power nacelle 32 in the vertical direction. The louvered rudder 35 is installed at the exhaust port of the power nacelle 32.

[0046] In this specific embodiment, there is one propeller 4, which is horizontally mounted on the fuselage 1 body along the longitudinal axis, located between the fixed wing 11 and the horizontal tail fin 12. The transmission system 5 includes an output shaft 51, a main gear 511, a drive shaft 52, a driven gear 521, a rotor shaft 53, a universal joint 531, a propeller shaft 54, a horizontal clutch 55, and a vertical clutch 56. The universal joint 531 passes radially through the tilting mechanism 17, and the rotor shaft 53 is fixedly connected to the hub 21 through the universal joint 531. The main gear 511 is mounted on the output shaft 51 and is fixedly connected to the power output end of the engine 33. The driven gear 521 is mounted on the drive shaft 52 and is arranged perpendicular to the output shaft 51. The main gear 511 and the driven gear 521 are bevel gears, and the output shaft 51 and the drive shaft 52 transmit power through the meshing of the main gear 511 and the driven gear 521. In this specific embodiment, the main gear 511 and driven gear 521 are helical bevel gears, but straight bevel gears or curved bevel gears can also be used. The output shaft 51 is coaxially connected to the rotor shaft 53 via a vertical clutch 56. The drive shaft 52 is coaxially connected to the propeller shaft 54 ​​via a horizontal clutch 55, and the other end of the propeller shaft 54 ​​is fixedly connected to the propeller 4. The horizontal clutch 55 is used to disconnect or close the power transmission between the drive shaft 52 and the propeller shaft 54. The vertical clutch 56 is used to disconnect or close the power transmission between the output shaft 51 and the rotor shaft 53.

[0047] like Figure 8 , 11 As shown, in this specific embodiment, the tilting mechanism 17 can rotate around the pitch direction of the fuselage 1 to control the direction of the normal of the rotation plane of the rotor 2. The rotation plane of the rotor 2 is always perpendicular to the axis of the connected universal joint 531. The tilting mechanism 17 rotates around the pitch direction of the fuselage 1 and drives the universal joint 531 passing through it to rotate, so that the direction of the axis of the universal joint 531 changes, thereby making the normal of the rotation plane of the rotor 2 in two different states: vertical and backward tilt.

[0048] In this specific embodiment, the engine 33 and the lift fan 34 are fixed in series and installed in the power compartment 32 along the output shaft 51. Unlike the traditional method of constraining all six degrees of freedom, the engine 33 and the power compartment 32 restrict all degrees of freedom except for the rotation of the engine 33 around the output shaft 51. The engine 33 as a whole can rotate freely around the output shaft 51 within the power compartment 32, isolating the torsional torque transmission path between the engine 33 and the fuselage 1. The engine 33 can be a piston engine or a turboshaft engine. The engine 33 is balancing to ensure that the high-speed rotation of the engine 33 around the output shaft 51 is stable and without significant shaking or vibration. To accommodate the high-speed rotation of the engine 33 around the output shaft 51, the fuel tank and fuel supply system should also be adjusted to adopt a synchronous high-speed rotation around the output shaft or a rotational fuel supply method.

[0049] like Figure 5 , 6As shown in Figures 7 and 8, in this specific embodiment, the blade design of the propeller 4 ensures that it rotates under the drive of the power system 3 and the transmission system 5, pushes the surrounding air backward, and obtains a forward reaction force.

[0050] like Figure 7 , 8 As shown, in this specific embodiment, the blade design of the rotor blades 22 and the lift fan 34 ensures that when both rotate in opposite directions around the output shaft 51, they both push the surrounding airflow downwards, generating upward lift. To meet the required rotational speeds of the propeller 4, rotor blades 22, and lift fan 34 during operation, the engine 33 in this specific embodiment also includes a reduction gear mechanism. The reduction gear mechanism can also be located at other positions along the transmission path of the propeller 4, or it can be achieved by adjusting the gear ratio of the main gear 511 and the driven gear 521; there is no substantial difference.

[0051] like Figure 8 As shown, in this specific embodiment, the engine 33, lift fan 34, transmission system 5, and rotor 2 maintain angular momentum conservation during rotation. That is, the engine 33 drives the rotor 2 to rotate at high speed through the transmission system 5 to generate lift. The reverse torque generated by the reaction between the rotor 2 and the air is transmitted through the transmission system 5 to drive the engine 33 and the lift fan 34 fixed to it to rotate in the opposite direction to generate additional lift. This is not transmitted to the fuselage 1 to cause the fuselage 1 to reverse. The reverse torque generated by the reverse rotation of the rotor 2, engine 33, and lift fan 34 combination acting on the air is balanced with each other.

[0052] like Figure 8 , 9 As shown in Figure 10, in this specific embodiment, the louvered rudder 35 is a set of four rudders located at the exhaust port of the engine compartment 32. The four rudders divide the exhaust port into four sectors. Each rudder can independently control the deflection direction. By deflecting in the same direction or differentially, the airflow direction of the exhaust port can be changed. When the helicopter is flying at low speed or hovering, the left and right tilt, pitch, and yaw of the fuselage 1 can be controlled. It can also be used in conjunction with the elevator 13 and rudder 15 to improve the maneuverability of the helicopter during normal flight.

[0053] The mechanism and process of achieving high-speed flight and control in this specific embodiment are explained below:

[0054] The first step is for the helicopter to take off vertically and hover.

[0055] When the helicopter is parked horizontally on the ground, both the horizontal clutch 55 and the vertical clutch 56 are disengaged. The tilt mechanism 17 is adjusted so that the normal to the plane of rotation of the rotor 2 is vertical. The engine 33 is started, and the vertical clutch 56 is engaged. The torque output by the engine 33 drives the rotor 2 to rotate at high speed through the output shaft 51, the vertical clutch 56, and the rotor shaft 53, driving the surrounding air downward to generate lift. At the same time, the reverse torque generated by the rotation of the rotor 2 and the interaction with the air acts on the engine 33, driving the engine 33 to rotate in the opposite direction to the rotation of the rotor 2, and driving the lift fan 34 to rotate, driving the outside air into the engine compartment 32 through the air intake 31. The air in the engine compartment 32 moves downward to generate lift. The reverse torque generated in the whole process is not transmitted to the fuselage 1, and the fuselage 1 will not rotate. The angular momentum of the rotor 2, rotor shaft 53, vertical clutch 56, output shaft 51, engine 33, and lift fan 34 is equal in magnitude and opposite in direction, and the total angular momentum is zero.

[0056] Increase the output power of engine 33, and the helicopter rises vertically under the lift generated by the rotation of rotor 2 and lift fan 34. After reaching the desired altitude, reduce the output power of engine 33 so that the lift generated by the rotation of rotor 2 and lift fan 34 is equal to the helicopter's weight, and the helicopter enters a hovering state. Looking forward from the tail of the helicopter, when the helicopter is disturbed by lateral airflow and tilts to the left, all the louvered rudders 35 deflect counterclockwise. The exhaust gas from the engine compartment 32 acts on the control surfaces of the louvered rudders 35, forming an aerodynamic force pointing to the left of the helicopter. This creates a clockwise torque along the longitudinal direction of the fuselage 1 on the helicopter's center of gravity, pushing the helicopter back to the right. When the helicopter tilts to the right, the opposite operation is performed. Looking forward from the tail of the helicopter, when the helicopter needs to turn to the right, the two sets of louvered rudders near the nose of the fuselage deflect clockwise, and the two sets of rudders near the tail of the fuselage deflect counterclockwise. Deflection: When viewed from directly above the helicopter, the aerodynamic force generated by the exhaust gas from the engine compartment 32 acting on the control surfaces of the louvered rudder 35 creates a torque that rotates clockwise around the vertical axis, pushing the helicopter nose to the right. When the helicopter needs to turn left, the opposite operation is performed. When the helicopter needs to pitch up, the two sets of rudders near the tail of the fuselage 1 of the louvered rudder 35 deflect to completely close the rear half of the exhaust port. The exhaust gas from the engine compartment 32 creates a pitching moment relative to the center of mass, increasing the helicopter's pitch angle. When the helicopter needs to pitch down, the opposite operation is performed.

[0057] The second step is for the helicopter to fly horizontally at low to medium speeds.

[0058] When the helicopter is hovering, the horizontal clutch 55 is engaged, and the output power of the engine 33 is moderately increased. At this time, part of the torque output by the engine 33 drives the rotor 2 to rotate at high speed through the output shaft 51, vertical clutch 56, and rotor shaft 53 to generate lift, and the other part drives the propeller 4 to rotate at high speed through the output shaft 51, drive shaft 52, horizontal clutch 55, and propeller shaft 54 ​​to generate thrust that propels the helicopter forward. Simultaneously, the reversible torque generated by the rotation of rotor 2 and its interaction with the air acts on engine 33, driving engine 33 to rotate in the opposite direction to rotor 2, and driving lift fan 34 to rotate. This drives external air into engine compartment 32 through air intake 31. The downward airflow in engine compartment 32 generates lift. Throughout this process, the reversible torque generated is not transmitted to fuselage 1, and fuselage 1 does not rotate. The angular momentum of rotor 2, rotor shaft 53, vertical clutch 56, output shaft 51, engine 33, and lift fan 34 is equal in magnitude and opposite in direction, resulting in a total angular momentum of zero. The reversible torque generated by propeller 4 is relatively small. During the helicopter's forward movement, the airflow over fuselage 1 and fixed wing 11 generates lift and resistance that inhibits the roll motion of fuselage 1 around its longitudinal axis. The effect of the reversible torque generated by propeller 4 on fuselage 1 can be ignored. The helicopter accelerates under the horizontal thrust generated by propeller 4 until the air resistance on the helicopter equals the horizontal thrust generated by propeller 4, at which point the helicopter enters a constant speed level flight state. At this time, the incoming flow velocity is relatively large, which can generate sufficient control force on the elevator 13 and rudder 15. By controlling the left and right deflection of the rudder 15, the helicopter can yaw left and right. The up and down deflection of the elevator 13 can increase or decrease the pitch angle of the helicopter. The two elevators 13 can achieve differential lifting and lowering to achieve the roll control of the helicopter.

[0059] Step 3: High-speed helicopter flight.

[0060] When the helicopter is in constant-speed level flight, the output power of engine 33 is increased, and the vertical clutch 56 is disengaged, causing rotor 2 to be unloaded and in a low-load or near-unloaded state. This reduces air resistance on rotor 2 and eliminates the reverse torque on fuselage 1 and engine 33. The helicopter's lift is primarily generated by the high-speed airflow over fuselage 1 and fixed wings 11. All the power output from engine 33 drives rotor 4 at high speed via output shaft 51, drive shaft 52, horizontal clutch 55, and rotor shaft 54, generating thrust that propels the helicopter forward. The reverse torque generated by rotor 4 is relatively small. During forward flight, the airflow over fuselage 1 and fixed wings 11 generates not only lift but also resistance that inhibits the roll motion of fuselage 1 around its longitudinal axis; the effect of the reverse torque generated by rotor 4 on fuselage 1 is negligible. Driven by the horizontal thrust generated by rotor 4, the helicopter further accelerates until the air resistance on the helicopter is equal to the horizontal thrust generated by rotor 4, at which point the helicopter enters high-speed level flight.

[0061] The helicopter deceleration unit performs the reverse process when landing.

[0062] In addition, in this specific embodiment, the high-speed helicopter, besides the normal mode, also has the function of switching to autogyro mode, which is suitable for needs such as reducing fuel consumption during medium and low speed cruise and emergency autogyro landing when the power system is damaged. The switching method is as follows:

[0063] like Figure 12 As shown, during flight or on the ground, the tilt mechanism 17 is adjusted so that the normal to the rotation plane of rotor 2 tilts backward. The vertical clutch 56 disengages, the engine 33 operates normally, and the horizontal clutch 55 remains closed, transforming the helicopter into an autogyro. At this time, airflow over the fuselage 1 and fixed wing 11 generates lift. Rotor 2 is driven to rotate by the oncoming airflow, generating lift, and the rotation of rotor 2 does not produce reverse torque on the engine 33 or fuselage 1. The torque output by engine 33 drives rotor 4 to rotate at high speed via output shaft 51, drive shaft 52, horizontal clutch 55, and propeller shaft 54, generating thrust that propels the helicopter forward. The reverse torque generated by propeller 4 is relatively small. During the helicopter's forward movement, the airflow over fuselage 1 and fixed wing 11 generates not only lift but also resistance that inhibits the roll motion of fuselage 1 around its longitudinal axis; therefore, the effect of the reverse torque generated by propeller 4 on fuselage 1 can be ignored. Driven by the horizontal thrust generated by propeller 4, the helicopter accelerates until the air resistance experienced by the helicopter is equal to the horizontal thrust generated by propeller 4, at which point the helicopter enters autorotator mode and flies at a constant speed.

[0064] The beneficial technical effects achieved by this specific embodiment are:

[0065] A single-rotor, tail-rotor-less high-speed helicopter solution was achieved by employing an engine-following mechanism. The traditional fixed-mount engine to the fuselage was replaced with an engine that retains rotational freedom around its output shaft, isolating the torsional torque transmission path between the engine and fuselage. The counter-torsional torque generated by the high-speed rotation of the rotor and its interaction with the air is transmitted through the transmission system, driving only the engine to rotate in the opposite direction, without being transmitted to the fuselage. This eliminates the need for a tail rotor and its associated power system for torque balancing. Simultaneously, a lift fan is coaxially and series-mounted with the engine's output shaft. This lift fan generates additional lift by rotating synchronously in the opposite direction to the engine. Furthermore, the counter-torsional torque generated by the rotor, engine, and lift fan assembly rotating in opposite directions balances each other. Because the tail rotor is eliminated, the engine no longer needs to provide 15% of its power to drive it, significantly improving engine energy efficiency. Compared to a coaxial dual-rotor design, a single rotor experiences less air resistance, enabling higher flight speeds with the same aerodynamic layout and power system output. It also allows the use of currently mature rotor and hub designs and materials, avoiding the significant cost and weight increases associated with high-strength, high-rigidity coaxial dual-rotor designs. A single power system achieves triple drive from the rotor, propeller, and lift fan, transforming the traditional energy-consuming reverse torque into lift-generating fan power. The engine compartment outlet is equipped with louvered rudders, providing tilt and directional control at low speeds and during hovering, further enhancing maneuverability. It features dual-mode switching between helicopter and autorotor, catering to low-speed, low-power, and low-fuel-consumption reconnaissance and search and rescue applications. Furthermore, it can land in autorotation mode if the power system is damaged, further improving safety. In addition, the design principle of this invention is simple, eliminating complex structures and control systems such as tilt rotors, significantly improving system reliability, economy, and service life.

[0066] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-speed helicopter with an engine that follows rotation and operates in a multi-mode compound configuration, comprising a fuselage (1), a rotor (2), a power system (3), and a transmission system (5), characterized in that, The high-speed helicopter also includes a propeller (4); the power system (3) includes an air intake (31), a power compartment (32), an engine (33), a lift fan (34), and a louvered rudder (35); the transmission system (5) includes an output shaft (51), a main gear (511), a drive shaft (52), a driven gear (521), a rotor shaft (53), a universal joint (531), a propeller shaft (54), a horizontal clutch (55), and a vertical clutch (56); the rotor (2) includes a hub (21) and at least two rotor blades (22) mounted on the hub (21); The fuselage (1) is a structure that carries the equipment on the aircraft and maintains the aerodynamic shape required for flight, including two fixed wings (11) symmetrically located on both sides of the middle, a horizontal tail (12), elevator (13), vertical tail (14), rudder (15) located at the tail, landing gear (16) located at the bottom, and a tilting mechanism (17) located at the top. The power compartment (32) is fixedly installed at the bottom of the fuselage (1) and is provided with an air inlet and an exhaust outlet. The air inlet is connected to the air intake duct (31), and the opening of the air intake duct (31) faces the head of the fuselage (1). The engine (33) and the lift fan (34) are coaxially connected in series and installed in the power compartment (32) along the output shaft (51). Only one degree of freedom is left between the engine (33) and the power compartment (32) for the engine (33) to rotate around the output shaft (51), isolating the torsional torque transmission path between the engine (33) and the fuselage (1). The engine (33) is balancing and rotates freely around the output shaft (51) in sync with the lift fan (34). The louvered rudder (35) includes four sets of rudders located at the exhaust port of the engine compartment (32), dividing the exhaust port into four sectors. Each set of rudders independently controls the deflection direction. By deflecting in the same direction or differentially, the airflow direction of the exhaust port is changed, which is used to control the high-speed helicopter to pitch, yaw, and roll. The output shaft (51) is fixedly connected to the power output end of the engine (33). A main gear (511) is mounted on the output shaft (51). The transmission shaft (52) is perpendicular to the output shaft (51). A driven gear (521) is mounted on the transmission shaft (52). The output shaft (51) and the transmission shaft (52) transmit power through the meshing of the main gear (511) and the driven gear (521). The transmission shaft (52) is coaxially connected to the propeller shaft (54) through the horizontal clutch (55). The other end of the propeller shaft (54) is fixedly connected to the propeller (4). The output shaft (51) is coaxially connected to the rotor shaft (53) through the vertical clutch (56). The rotor shaft (53) is fixedly connected to the hub (21) of the rotor (2) through the universal joint (531). The universal joint (531) passes radially through the tilting mechanism (17). The horizontal clutch (55) is used to cut off or close the power transmission between the drive shaft (52) and the propeller shaft (54), and the vertical clutch (56) is used to cut off or close the power transmission between the output shaft (51) and the rotor shaft (53). The rotor (2) and the lift fan (34) rotate in opposite directions around the output shaft (51), and the blade structure is designed to push the airflow around them downwards, thus obtaining upward lift. The propeller (4) is designed to push the surrounding air backwards when it rotates under the drive of the power system (3) and the transmission system (5), thus obtaining forward reaction force.

2. The high-speed helicopter according to claim 1, characterized in that, The tilting mechanism (17) rotates around the pitch direction of the fuselage (1), causing the universal joint (531) passing through it to rotate as well, changing the orientation of the universal joint (531) shaft, so that the normal of the rotation plane of the rotor (2) is in two different states: vertical and backward tilt. In conjunction with the vertical clutch (56) closing / disclosing, the helicopter / autogyro mode can be switched.

3. The high-speed helicopter according to claim 1, characterized in that, The engine (33) drives the rotor (2) to rotate at high speed through the transmission system (5) to generate lift. The reverse torque generated by the rotor (2) interacting with the air is transmitted through the transmission system (5) to drive the engine (33) and the lift fan (34) fixed to it to rotate in the opposite direction to generate additional lift. The reverse torque generated by the rotor (2), engine (33) and lift fan (34) combination rotating in the opposite direction and acting on the air is balanced.

4. The high-speed helicopter according to claim 1, characterized in that, The engine (33) also includes a reduction gear mechanism.

5. The high-speed helicopter according to claim 1, characterized in that, The engine (33) is a piston engine or a turboshaft engine.

6. The high-speed helicopter according to claim 1, characterized in that, The main gear (511) and driven gear (521) are helical bevel gears, straight bevel gears or curved bevel gears.

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