A variable pitch vertical take-off and landing fixed wing

Abstract

The application discloses a variable-pitch vertical take-off and landing fixed wing, which comprises a fuselage, a front wing, a main wing, a vertical tail, a power base pipe, a power input unit, a double-end variable speed device, a clutch system, a level flight cruising variable-pitch device and a vertical hovering variable-pitch device. The variable-pitch vertical take-off and landing fixed wing provided by the application can controllably expand and retract the propeller through the cooperation of the clutch system and the variable-pitch device, can switch the corresponding propeller according to different flight states of the aircraft, and can make the vertical take-off and landing fixed wing use the propeller suitable for the respective state in the vertical hovering state and the level flight cruising state, so that the aircraft has a long endurance time, a high flight speed and a wide application range.

Description

TECHNICAL FIELD

[0001] The present application describes a variable pitch device for controllable deployment and stowage of propellers, realizing power conversion between two flight states of flat cruising and vertical hovering, belonging to the field of aerospace, in particular, a variable pitch vertical take-off and landing fixed wing. BACKGROUND

[0002] The vertical take-off and landing fixed wing is a kind of fixed wing aircraft with vertical take-off and landing capability, which does not depend on the runway and has low requirements for the landing site, can take off and land in place, and can cruise efficiently in the fixed wing state. The existing vertical take-off and landing fixed wing has some deficiencies: first, the tilt type vertical take-off and landing fixed wing, due to the limitation of propellers, the corresponding propeller aerodynamic shape design direction of flat flying and vertical hovering is completely opposite. If the power design is biased towards flat cruising, it will result in low power efficiency when taking off vertically at a large take-off weight, high hovering power consumption, affecting endurance, and even difficult to take off. If the power design is biased towards vertical hovering, it will result in rapid decay of propeller power with increasing speed at a large take-off weight, low flat flying speed, low flat flying efficiency, and even power decay to the point where flat flying cannot be maintained. It is difficult to achieve a good balance between flat flying efficiency and hovering load, and the flight control system and tilt power structure of the aircraft require a large amount of test and test data for optimization of the control software in various working states, and the technical threshold is relatively high.

[0003] Secondly, the current tilt type vertical take-off and landing fixed wing has appeared in the market in large quantities, which changes the power direction through the tilt engine nacelle or the entire wing, realizes the mutual conversion of vertical take-off and flat cruising flight, and the tilt driving mechanism needs to bear the torque of the entire engine nacelle or the entire wing rotation. The strength, wear resistance and other mechanical properties of its parts and driving power have high requirements, so the weight of the tilt driving mechanism part is a very large dead weight for flat cruising and vertical hovering, which seriously affects the endurance and payload of the aircraft.

[0004] Thirdly, the compound wing vertical take-off and landing fixed wing has good power efficiency due to the separation type power matching, but it is essentially a direct combination of multi-rotor aircraft and fixed wing aircraft. The dead weight and wind resistance caused by the weight of the multi-rotor power and structure greatly weaken the cruising performance, resulting in slow flight speed, short endurance time and low work efficiency. SUMMARY

[0005] In view of the deficiencies of the prior art, the present application provides a variable-pitch vertical take-off and landing fixed wing, I. During flight, when the flight parameters such as the height, speed and attitude angle of the aircraft reach the power switching condition during the conversion of the aircraft from vertical hovering state to flat flying cruising state, the vertical hovering blades are retracted and the flat flying cruising blades are unfolded through the work of the clutch system and the variable-pitch device, so that the flat flying cruising blades become the power for the fixed wing mode flight. In the case that the aircraft is equipped with a set of power source, two sets of propellers are carried, and the corresponding propeller can be switched according to the different flight states of the aircraft, so that the vertical take-off and landing fixed wing uses the propeller suitable for each state in the vertical hovering and flat flying cruising two different states, solving the problem that the tilt type and tail stand type vertical take-off and landing fixed wing cannot simultaneously consider the best power output efficiency in the two states due to using the same power source and the same propeller. II. The variable-pitch device of the variable-pitch vertical take-off and landing fixed wing only controls the controllable unfolding and retraction of the propeller, realizes the switching of the propeller, greatly reduces the complexity and weight of the device compared with the scheme of retracting the whole power unit, and solves the problems of short endurance, small load, large dead weight and large wind resistance of the existing vertical take-off and landing fixed wing.

[0006] The present application is realized by the following measures:

[0007] A variable-pitch vertical take-off and landing fixed wing, comprising a fuselage, a front wing, a main wing, a vertical tail, a power base pipe, a power input unit, a double-end variable speed device, a clutch system, a vertical hovering propeller, a flat flying cruising propeller, a controllable folding variable-pitch device, a propeller retraction brake system, a folding driver, a taxiing landing gear and a vertical take-off and landing support foot.

[0008] The clutch system comprises a flat flying cruising power clutch and a vertical hovering power clutch, the controllable folding variable-pitch device comprises a flat flying cruising variable-pitch device and a vertical hovering variable-pitch device, the flat flying cruising propeller and the vertical hovering propeller use the same power source, the power is generated by the power input unit, passes through the double-end variable speed device and the clutch system, and is respectively transmitted to the flat flying cruising propeller and the vertical hovering propeller, and the clutch system controls the connection and disconnection of the power of the flat flying cruising propeller and the vertical hovering propeller. When the variable-pitch vertical take-off and landing fixed wing is in vertical take-off and hovering, the clutch system connects the power of the vertical hovering propeller and disconnects the power of the flat flying cruising propeller, at the same time, the vertical hovering variable-pitch device unfolds the vertical hovering propeller and the flat flying cruising variable-pitch device retracts the flat flying cruising propeller, and the vertical hovering propeller is enabled. When the variable-pitch vertical take-off and landing fixed wing is in flat flying cruising and high-speed flight, the clutch system connects the power of the flat flying cruising propeller and disconnects the power of the vertical hovering propeller, at the same time, the flat flying cruising variable-pitch device unfolds the flat flying cruising propeller and the vertical hovering variable-pitch device retracts the vertical hovering propeller, and the flat flying cruising propeller is enabled.

[0009] The front wing inner end is rigidly connected with the fuselage, the main wing inner end is rigidly connected with the fuselage, and the power base pipe is rigidly connected with the front wing and the main wing at two ends respectively; the power input unit, the double-end speed change device, the level flight cruising power clutch, the vertical hovering power clutch, the level flight cruising variable pitch device and the vertical hovering variable pitch device are symmetrically installed on the power base pipe.

[0010] The vertical tail is rigidly connected with the tail of the fuselage and is provided with a rudder, and the vertical tail can be one installed on the tail of the fuselage or two vertical tails symmetrically installed on the two main wings.

[0011] Further, the power input unit transmits the power of the engine to the level flight cruising power clutch and the vertical hovering power clutch through the double-end speed change device, and the two output ends of the double-end speed change device generate different speed change ratios.

[0012] Further, the variable pitch vertical take-off and landing fixed wing can realize the taxiing take-off and landing and the vertical take-off of the aircraft according to different task requirements. When taking off vertically, the fuselage is perpendicular to the ground, before the power system is started, the controllable folding variable pitch device controls the expansion of the vertical hovering propeller, the clutch for vertical hovering is in contact with the propeller seat of the vertical hovering variable pitch device, the power input of the vertical hovering propeller is in a connected state, the level flight cruising variable pitch device controls the retraction of the level flight cruising propeller, the clutch for level flight cruising is separated from the propeller seat of the level flight cruising variable pitch device, the power input of the level flight cruising propeller is in a disconnected state, the power system is started to drive the vertical hovering propeller to rotate to generate lift and complete take-off; when the aircraft is in a level flight cruising state, the vertical hovering variable pitch device controls the retraction of the vertical hovering propeller, the clutch for vertical hovering is separated from the propeller seat of the vertical hovering variable pitch device, the power input of the vertical hovering propeller is in a disconnected state, the level flight cruising variable pitch device controls the expansion of the level flight cruising propeller, the clutch for level flight cruising is in contact with the propeller seat of the level flight cruising variable pitch device, the power input of the level flight cruising propeller is in a connected state, and the level flight cruising propeller rotates to work.

[0013] The controllable folding variable-pitch device includes a cruising variable-pitch device and a vertical hovering variable-pitch device, and is composed of a propeller base and a propeller, a transmission rod; the propeller base has a friction surface with a large friction coefficient; the rotating driving moment of the propeller base and the propeller is transmitted from the friction surface of the propeller base through the power connection with a clutch system; the propeller base is sleeved on a power base pipe and can rotate freely relative to the power base pipe; the propeller base has an ear piece outside the propeller base, which is connected to the root of the propeller to enable the propeller base to rotate relative to the root of the propeller in a direction perpendicular to the power rotation axis; the propeller transmission rod has one end connected to the root of the propeller through a rotating shaft to enable the propeller to rotate relative to the propeller, and the other end connected to the ear piece on the rotating transmission ring through a rotating shaft to enable the rotating transmission ring to rotate relative to the rotating transmission ring in a direction perpendicular to the power rotation axis.

[0014] Further, the vertical take-off support foot is installed in the direction of the tail of the fuselage, the sliding take-off gear is started in the sliding take-off of the aircraft and is retracted in other working states, and the vertical take-off support foot is unfolded in the vertical take-off or hovering working state of the aircraft; the vertical take-off support foot can stabilize the fuselage when the aircraft is vertically parked on the ground.

[0015] Further, the cruising propeller is unfolded in the cruising state and is retracted in the vertical hovering state, and the vertical hovering propeller is unfolded in the vertical hovering state and is retracted in the cruising state.

[0016] Further, the cruising power clutch and the vertical hovering power clutch are connected and disconnected under the action control of the retraction and unfolding of the cruising variable-pitch device and the vertical hovering variable-pitch device.

[0017] The cruising variable-pitch device is disconnected from the power by the cruising power clutch when being retracted and is connected to the power by the cruising power clutch when being unfolded; the vertical hovering variable-pitch device is disconnected from the power by the vertical hovering power clutch when being retracted and is connected to the power by the vertical hovering power clutch when being unfolded.

[0018] Further, the cruising variable-pitch device is unfolded when the vertical hovering variable-pitch device is retracted, which can meet the normal sliding take-off of the aircraft; the power input mode of the power input unit of the variable-pitch vertical take-off fixed wing can be electric or oil depending on the engine type.

[0019] When the propeller base of the cruising variable-pitch device is in contact with and pressed against the clutch, the engine power is transmitted to the propeller base; the propeller base is sleeved on the power base pipe and rotates around the axis of the power base pipe to drive the cruising propeller to rotate and generate a pulling force.

[0020] The one side of the paddle base of the vertical hovering paddle device is close to the clutch. When the clutch is in contact and pressed, the engine power is transmitted to the paddle base, the paddle base is sleeved on the power base pipe, and the power base pipe axis is rotated to drive the vertical hovering propeller to rotate to generate lift.

[0021] Further, the controllable folding variable paddle device is driven by the servo motor to rotate the propeller around its root shaft through the paddle transmission rod to control the folding and unfolding of the paddle.

[0022] The double-end variable speed device has two structural forms. One is a parallel shaft planetary reducer. The power input unit is generally a double-shaft motor connected with two planetary reducers, fixed on the bracket of the double-end variable speed device. The bracket is fixed with the power base pipe. The power input unit is coaxially installed with the planetary reducer and the output gear. The power input unit transmits power through the two-end planetary reducer and then through the primary gear transmission to transmit power to the horizontal flight suspension power clutch and the vertical hovering power clutch respectively. If the power input unit is selected, the rotational speed after transmission through the output gear matches the working rotational speed of one end of the propeller. The transmission ratio of this end is 1. Therefore, the planetary reducer is not needed and can be directly hard connected with the output gear.

[0023] Another feasible structural form of the double-end variable speed device is a vertical shaft bevel gear reducer, which includes an input end bevel gear, an output end small bevel gear, an output end large bevel gear, and an engine. The engine input power is transmitted through the two groups of different size bevel gears to achieve different transmission ratios. The two different size bevel gears are coaxially fixed on the input shaft. The input end bevel gear is perpendicular to the axes of the output end small bevel gear and the output end large bevel gear. The input end bevel gear is fixed through the power base pipe. The vertical shaft bevel gear reducer has the characteristics of simple structure and flexible power matching. The power input is generally an oil engine.

[0024] Further, the vertical shaft bevel gear reducer has a power input unit, which is generally an oil engine, such as a gasoline engine and a turbo shaft engine, or an electric motor.

[0025] The paddle brake system is composed of a brake disc fixed on the power base pipe and a protrusion on the rotating transmission ring. The brake disc is arranged in the direction of the paddle tip after the paddle is folded. The side facing the paddle tip is a friction contact surface with a high friction coefficient. The side of the protrusion on the rotating transmission ring facing the brake disc is a friction contact surface with a high friction coefficient.

[0026] Further, the retractable drive moves the translation transmission ring and the rotating transmission ring, so that when the propeller is retracted to the minimum resistance state, the friction contact surface of the protrusion on the rotating transmission ring and the friction contact surface of the brake disc are in contact with each other, and the rotation of the rotating transmission ring and the propeller is hindered by the generated friction force.

[0027] Further, the propeller brake system starts to work after the folding action is completed, so as to stop the rotation of the propeller and other parts rotating with the propeller, and keep the static state, avoiding the loss of aircraft kinetic energy caused by air flow blowing rotation.

[0028] The folding and unfolding driver is composed of a worm wheel, a worm wheel shaft, a worm, a gear, a rack, and a servo motor, and generates a translation movement according to a control electric signal, and drives the forward and backward movement of the rotation transmission ring of the controllable folding and variable pitch device.

[0029] Further, the rack is fixed in a groove in the inner ring of the translation transmission ring, the gear is engaged with the rack, the gear is fixed at both ends of the worm wheel shaft, the worm wheel is coaxially fixed with the worm wheel shaft at the center of the worm wheel shaft, the worm is perpendicular to the worm wheel shaft and engaged with the worm wheel, the servo motor is coaxially connected with the worm, drives the rotation of the worm, and further drives the rotation of the worm wheel, and further drives the forward and backward movement of the rack and the translation transmission ring, and further drives the folding or unfolding of the propeller.

[0030] Further, the rocker arm is installed at the extended part of the propeller seat and the rotating shaft of the propeller, one end of the rocker arm is fixed on the rotating shaft, and the other end is fixed with the clutch transmission rod through a rotating shaft, and the clutch transmission rod can rotate relative to the clutch transmission rod, the clutch transmission rod and the clutch transmission ring are driven to move when the pitch is changed, and the connection and disconnection of the clutch are linked to the pitch changing action, so that the propeller is opened at the same time, the clutch is automatically connected and power is transmitted, and the propeller is folded at the same time, the clutch is automatically disconnected and power is transmitted.

[0031] Beneficial effects:

[0032] 1. The variable pitch vertical take-off and landing fixed wing provided by the application can maximize the hovering efficiency and load advantage of the propeller optimized for vertical hovering when hovering vertically, and can provide efficient power input for the propeller optimized for high-speed cruising when cruising, and the power is transmitted through the double-end speed changing device, so that the matching of the different working speeds of the propellers in the two flight states is realized simply and naturally, so that the vertical take-off and landing fixed wing has the high-speed long-endurance advantage of a pure fixed-wing aircraft, the high-efficiency vertical hovering capacity of a pure helicopter and a multi-rotor, and the dead weight and wind resistance ratio of the compound wing vertical take-off and landing fixed wing is much smaller, the working efficiency is high, and the application range is wide.

[0033] 2. The variable-pitch device of the variable-pitch vertical take-off and landing fixed-wing aircraft, only by unfolding and folding the propeller, the required two powers of the tail stand type vertical take-off and landing fixed-wing aircraft are switched, compared with the tilt type vertical take-off and the scheme of folding the entire power unit, the complexity and weight of the device are greatly reduced, and the material performance requirements of the device parts are not high, and the material cost is low. BRIEF DESCRIPTION OF DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show the embodiments of the present application and should not be considered as limiting the scope. For those skilled in the art, other related drawings can also be obtained from these drawings without creative labor.

[0035] Figure 1 Typical scheme of variable-pitch vertical take-off and landing fixed-wing aircraft in flat cruising mode

[0036] Figure 2 Typical scheme of variable-pitch vertical take-off and landing fixed-wing aircraft in vertical take-off and landing, hovering mode

[0037] Figure 3 Composition diagram of variable-pitch power system of variable-pitch vertical take-off and landing fixed-wing aircraft

[0038] Figure 4 Variable-pitch axial view of variable-pitch vertical take-off and landing fixed-wing aircraft

[0039] Figure 5 Variable-pitch overhead view of variable-pitch vertical take-off and landing fixed-wing aircraft

[0040] Figure 6 Vertical axis power input schematic diagram of variable-pitch vertical take-off and landing fixed-wing aircraft

[0041] Figure 7 Parallel shaft power input schematic diagram of double-end variable speed device

[0042] Figure 8 Vertical axis power input schematic diagram of double-end variable speed device

[0043] Figure 9 Variable-pitch vertical take-off and landing fixed-wing aircraft vertical axis power input vertical take-off and hovering power variable-pitch schematic diagram

[0044] Figure 10 Three-blade propeller diagram of variable-pitch vertical take-off and landing fixed-wing aircraft

[0045] Figure 11 Variable-pitch device exploded view

[0046] Figure 12 Enlarged view of the translation transmission ring.

[0047] Figure 13Variable pitch device stowed state diagram

[0048] Figure 14 Variable pitch device stowed state diagram

[0049] Figure 15 Variable pitch device stowed state diagram

[0050] Figure 16 Variable pitch device stowed state diagram

[0051] In the figure: 1 power input unit, 2 double-ended transmission, 2A support, 2B planetary reducer, 3 cruise power clutch, 4 cruise variable pitch device, 5 vertical hovering power clutch, 6 vertical hovering variable pitch device, 7 power base tube, 8 fuselage, 9 front wing, 10 main wing, 11 vertical tail, 12 front wing elevator, 13 aileron, 14 rudder, 15 flap, 16 front landing gear, 17 taxi landing gear, 18 vertical take-off and landing support foot, 19 cruise propeller, 20 vertical hovering propeller, 21 propeller seat, 22 propeller, 23 propeller blade transmission rod, 24 rotation transmission ring, 25 translation transmission ring, 26 rack, 61 brake disc, 62 brake protrusion, 71 worm, 72 worm wheel, 30 clutch, 31 clutch rocker arm, 32 clutch transmission ring, 33 clutch transmission rod, 51 input bevel gear, 52 output small bevel gear, 53 output large bevel gear, 54 engine. DETAILED DESCRIPTION

[0052] Example 1:

[0053] As Figure 1 , 2 , 3, 4, 5, a variable pitch vertical take-off and landing fixed wing, comprising: 1 power input unit, 2 double-ended transmission, 3 cruise power clutch, 4 cruise variable pitch device, 5 vertical hovering power clutch, 6 vertical hovering variable pitch device, 7 power base tube, 8 fuselage, 9 front wing, 10 main wing, 11 vertical tail, 12 front wing elevator, 13 aileron, 14 rudder, 15 flap, 16 front landing gear, 17 main landing gear, 18 vertical take-off and landing support foot, 19 cruise propeller, 20 vertical hovering propeller, 21 propeller seat, 23 propeller blade transmission rod.

[0054] The fuselage 8 is rigidly connected with the inner end of the front wing 9, the outer end of the front wing 9 is rigidly connected with the power base pipe 7, the inner side edges of the front wing 9 are connected with the main wing 10 and the front wing elevator 12, the inner end of the main wing 10 is rigidly connected with the fuselage 8, the outer end of the main wing 10 is rigidly connected with the power base pipe 7, the tail of the main wing 10 is connected with the aileron 13 and the flap 15, the vertical tail 11 is rigidly connected with the tail of the fuselage 8 and is provided with the rudder 14, the vertical take-off and landing support leg 18 is installed at the tail of the fuselage 8, the front landing gear 16 and the main landing gear 17 constitute the taxiing and landing gear and are installed at the abdominal position of the fuselage and are connected with the overall structure of the fuselage 8, the power input unit 1, the double-end speed change device 2, the flat cruising power clutch 3, the vertical hovering power clutch 5, the flat cruising variable pitch device 4 and the vertical hovering variable pitch device 6 are all distributed and installed on the power base pipe 7.

[0055] The variable pitch vertical take-off and landing fixed wing has a flat cruising state and a vertical hovering state in the task process, the fuselage is parallel to the ground in the flat cruising state, the flat cruising propeller 19 is unfolded and the vertical hovering propeller 20 is folded in the flat cruising; the fuselage is vertical to the ground in the vertical hovering state, the flat cruising propeller 19 is folded and the vertical hovering propeller 20 is unfolded in the vertical hovering.

[0056] The power input unit 1 transmits the power of the engine or the motor to the flat cruising power clutch 3 and the vertical hovering power clutch 5 through the double-end speed change device 2, the double-end speed change device 2 makes the two different output ends produce different speed change ratios, the double-end speed change device acts on the different working speeds of the flat cruising propeller and the vertical hovering propeller, and the difference is large, it outputs two different speeds and torques after two different transmission ratios, so as to match the different working speeds and torques of the two propellers. And the power source of the power input unit 1 can be electric or oil-driven.

[0057] The flat cruising power clutch 3 and the vertical hovering power clutch 5 realize the connection and disconnection of the clutch power under the unfolding and folding actions of the flat cruising variable pitch device 4 and the vertical hovering variable pitch device 6, specifically, the flat cruising variable pitch device 4 disconnects the power by the flat cruising power clutch 3 when folding the propeller blades, and connects the power by the flat cruising power clutch 3 when unfolding the propeller blades, the vertical hovering variable pitch device 6 disconnects the power by the vertical hovering power clutch 5 when folding the propeller blades, and connects the power by the vertical hovering power clutch 5 when unfolding the propeller blades.

[0058] The controllable folding variable-paddle device, taking the flat cruising variable-paddle device 4 as an example, specifically, the paddle seat 21, the side close to the clutch, when in contact and compression with the clutch, the engine power is transmitted to the paddle seat 21, the paddle seat 21 is sleeved on the power base pipe 7, rotates around the axis of the power base pipe 7, and drives the flat cruising propeller 19 of the variable-paddle device to rotate to generate pulling force; the flat cruising propeller 19, one end of the flat cruising propeller 19 is movably connected with the paddle seat 21 through a rotating shaft, and the one end of the flat cruising propeller 19 is movably connected with the paddle blade transmission rod 23; under the driving of the servo motor, the flat cruising propeller 19 is driven to rotate around the root rotating shaft by the paddle blade transmission rod 23, so that the folding and unfolding of the propeller blade are controlled.

[0059] The flat cruising propeller 19 is unfolded by the flat cruising variable-paddle device 4 in the flat cruising state, and is folded in the vertical hovering state; the vertical hovering propeller 20 is unfolded by the vertical hovering variable-paddle device 6 in the vertical hovering state, and is folded in the flat cruising state; the folding directions of the flat cruising variable-paddle device 4 and the vertical hovering variable-paddle device 6 are opposite, and when the propellers are folded, the propeller tips move away from the clutch; it should be pointed out that the paddle blade forms of the flat cruising propeller 19 and the vertical hovering propeller 20 can be the double-paddle blades as shown in Figure 1 , or the triple-paddle blades as shown in Figure 10 .

[0060] Embodiment 2:

[0061] This embodiment mainly introduces two structural forms of the power input unit, one is as shown in Figure 7 , the double-end speed change device 2 is a parallel shaft planetary reducer, the power input unit 1 is generally a double-output shaft motor, which is connected with two planetary reducers 2B, and is fixed on the support 2A of the double-end speed change device, the support is fixed with the power base pipe 7, the power input unit 1 is coaxially installed with the planetary reducer 2B and the output gear, the power of the power input unit 1 is transmitted through the two-end planetary reducer 2B, and then is transmitted to the flat cruising power clutch 3 and the vertical hovering power clutch 5 through the primary gear transmission respectively. If the power input unit 1 is selected, the transmission ratio of one end is 1 after the transmission speed is transmitted through the output gear and matches the working speed of the propeller, then the planetary reducer is not needed, and the output gear can be directly hard-connected.

[0062] The other is as shown in Figure 6 , 8, 9, is another possible structure of the double-ended variable speed device, which can be called vertical shaft bevel gear reducer, including an input bevel gear 51, an output small bevel gear 52, an output large bevel gear 53, and an engine 54. The engine 54 inputs power through the two groups of different size bevel gears to achieve different transmission ratios. The two different size bevel gears are coaxially fixed on the input shaft, and the input bevel gear 51 is perpendicular to the axes of the output small bevel gear 52 and the output large bevel gear 53. The input bevel gear 51 is fixed through the power base tube 7. The vertical shaft bevel gear reducer has the characteristics of simple structure and flexible power matching. The power input is generally an oil engine, such as a gasoline engine and a turbo-shaft engine, or an electric motor.

[0063] Example 3:

[0064] As shown in Figure 11 、 12 , 13, 14, a controllable folding propeller device (the combination of the flat flight cruise variable pitch device 4 and the vertical hovering variable pitch device 6) includes a propeller seat 21, a propeller 22, a propeller blade transmission rod 23, a rotary transmission ring 24, a translation transmission ring 25, a rack 26, a brake disc 61, a brake protrusion 62, a worm 71, and a worm gear 72. The propeller seat 21, the rotary transmission ring 24, the translation transmission ring 25, and the folding and unfolding driver are all distributed and installed on the power base tube 7. The brake disc 61 and the brake protrusion 62 form a propeller folding brake system, and the worm 71 and the worm gear 72 form a folding and unfolding driver.

[0065] The propeller seat 21 has a friction surface with a large friction coefficient. The rotary driving moment of the propeller seat 21 and the propeller 22 is transmitted from the friction surface of the propeller seat 21 through the power connection with the clutch system. The propeller seat 21 is sleeved on the power base tube 7 and can rotate freely relative to the power base tube 7. The propeller seat 21 has an ear piece outside, which is connected to the root of the propeller 22 to enable the propeller 22 to rotate relative to the root of the propeller 22 around a direction perpendicular to the power rotation axis.

[0066] The propeller 22 has one end of the propeller 22 connected to the ear piece of the propeller seat 21 through a rotating shaft to enable the propeller 22 to rotate relative to the propeller seat 21. The root of the propeller 22 is connected to the propeller blade transmission rod 23 through a rotating shaft to enable the propeller 22 to rotate relative to the propeller blade transmission rod 23.

[0067] The propeller blade transmission rod 23 has one end connected to the root of the propeller 22 through a rotating shaft to enable the propeller 22 to rotate relative to the propeller 22. The other end is connected to the ear piece on the rotary transmission ring 24 through a rotating shaft to enable the propeller 22 to rotate relative to the rotary transmission ring 24 around a direction perpendicular to the power rotation axis. It should be noted that the propeller blade form in this embodiment includes but is not limited to the form of two-blade propeller. The single-blade propeller, three-blade propeller, four-blade propeller, and other forms similar to this structure all belong to the specific embodiments of the present application.Figure 15 、 16 The third leaf is in the form of a 3-leaf paddle.

[0068] The rotating transmission ring 24 has an external ear connected to the paddle transmission rod 23, which rotates relative to the paddle transmission rod 23 in a direction perpendicular to the power rotation axis, and is sleeved on the translation transmission ring 25.

[0069] The translation transmission ring 25 has a linear groove in the inner ring, which is clamped on the protruding linear guide rail of the power base pipe 7, and has an annular groove on the outer ring, which is coaxially sleeved with the rotating transmission ring 24. Under the drive of the retractable drive composed of the worm 71 and the worm wheel 72, the rotating transmission ring 24 moves forward and backward, the inner ring has a rack in the same direction as the linear groove, and the rack is engaged with the gear at both ends of the worm wheel 72.

[0070] The paddle retraction brake system is composed of a brake disc 61 fixed on the power base pipe 7 and a brake protrusion 62 on the rotating transmission ring 24. The brake disc 61 is arranged in the direction of the paddle tip after the paddle is retracted, and the side facing the paddle tip is a friction contact surface with a high friction coefficient. The side of the brake protrusion 62 on the rotating transmission ring 24 facing the brake disc 61 is a friction contact surface with a high friction coefficient. When the translation transmission ring 25 and the rotating transmission ring 24 are moved under the drive of the retractable drive composed of the worm 71 and the worm wheel 72, so that the propeller 22 is retracted to the minimum resistance state, the friction contact surface of the brake protrusion 62 on the rotating transmission ring 24 and the friction contact surface of the brake disc 61 are in contact with each other, generating friction to prevent the rotating transmission ring 24 and the propeller 22 from rotating. It should be noted that the paddle retraction brake system includes but is not limited to the brake disc form described above, and other brake systems that can stop the rotation of the propeller and the parts rotating synchronously with the propeller to maintain a stationary state also belong to the further improvement scheme of the invention and fall within the protection scope of the invention.

[0071] The retractable drive is mainly composed of a worm 71 and a worm wheel 72, and further includes a worm shaft on the worm wheel 72, gears on the worm 71 and the worm wheel 72, a rack 26 on the translation transmission ring 25, and a servo motor. The rack is fixed in the groove in the inner ring of the translation transmission ring 25, the gear is engaged with the rack 26, the gear is fixed at both ends of the worm shaft, the worm wheel 72 is coaxially fixed with the worm shaft at the center of the worm shaft, the worm 71 is perpendicular to the worm shaft and engaged with the worm wheel 72, and the servo motor is coaxially connected with the worm 71 to drive the rotation of the worm 71, thereby driving the rotation of the worm wheel 72, and further driving the forward and backward movement of the rack and the translation transmission ring 25, and further driving the retraction or expansion of the propeller 22. Since the worm and the worm wheel have self-locking characteristics in this embodiment, the state of the device can be maintained without power supply to the driving motor, thereby eliminating the need for the servo motor to generate torque when the propeller is expanded or retracted, and the device can itself be locked, reducing the energy consumption of the servo motor and prolonging the working life.

[0072] It should be further pointed out that the above-mentioned take-up and release drive, including but not limited to the above-mentioned worm and gear plus rack and pinion mode, other driving modes capable of driving the translational transmission ring to move in the direction of the power base tube axis, all belong to the further improvement scheme of the present application, and all belong to the protection scope of the present application.

[0073] Further, the propeller 22 is provided with a clutch rocker arm 31 at the rotating shaft of the propeller base 21, one end of the clutch rocker arm 31 is fixed on the rotating shaft, the other end is connected with the clutch transmission rod 33 through the rotating shaft, and the clutch transmission rod 33 can rotate relative to the clutch transmission rod 33. When the propeller is changed, the clutch transmission rod 33 and the clutch transmission ring 32 are driven, and the connection and disconnection action of the clutch 30 is linked, so that the propeller 22 is opened, and the clutch 30 is automatically connected with the power transmitted by the power input unit 1 at the same time. When the propeller 22 is retracted, the clutch 30 automatically disconnects the power transmitted by the power input unit 1 at the same time.

[0074] The above embodiments are only preferred embodiments of the present application, the gears in the embodiments are not limited to straight gears, and can also be helical gears or other transmission mechanisms, which can all achieve the technical scheme of the present application. However, the protection scope of the present application is not limited to this. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A variable-pitch vertical take-off and landing fixed wing, mainly comprising a fuselage, a front wing, a main wing, a vertical tail, a power base tube, a power input unit, characterized in that: Also includes double-ended transmission, clutch system, controllable folding variable-pitch device, vertical suspension propeller, flat cruising propeller; the vertical tail is a tail mounted on the fuselage or two vertical tail symmetrically mounted on two main wings; the clutch system includes flat cruising power clutch and vertical suspension power clutch, the flat cruising power clutch and vertical suspension power clutch are connected and separated by the connection of the flat cruising variable-pitch device and vertical suspension variable-pitch device, respectively, to realize the connection and disconnection of the power input of the flat cruising propeller and the vertical suspension propeller; the front wing inner end is rigidly connected with the fuselage, the main wing inner end is rigidly connected with the fuselage, and the power base pipe is rigidly connected with the front wing and the main wing at both ends; the power input unit, the double-ended transmission, the flat cruising power clutch, the vertical suspension power clutch, the flat cruising variable-pitch device and the vertical suspension variable-pitch device are symmetrically mounted on the power base pipe on both sides of the fuselage; the controllable folding variable-pitch device includes flat cruising variable-pitch device and vertical suspension variable-pitch device, the flat cruising propeller and the vertical suspension propeller use the same power source, the power is generated by the power input unit, transmitted to the flat cruising propeller and the vertical suspension propeller through the double-ended transmission and the clutch system, and the clutch system controls the connection and disconnection of the flat cruising propeller and the vertical suspension propeller; when the variable-pitch vertical take-off and landing fixed wing is vertically taking off and landing, the clutch system connects the power of the vertical suspension propeller and disconnects the power of the flat cruising propeller, at the same time, the vertical suspension variable-pitch device unfolds the vertical suspension propeller, and the flat cruising variable-pitch device folds the flat cruising propeller, enabling the vertical suspension propeller; When the variable-pitch vertical take-off and landing fixed wing is flat cruising and high-speed flying, the clutch system connects the power of the flat cruising propeller and disconnects the power of the vertical suspension propeller, at the same time, the flat cruising variable-pitch device unfolds the flat cruising propeller, and the vertical suspension variable-pitch device folds the vertical suspension propeller, enabling the flat cruising propeller.

2. A tiltrotor STOL fixed wing according to claim 1, characterized in that: The power input mode of the power input unit is different according to the selection of the engine, and the power input unit is electric or oil-driven.

3. A tiltrotor fixed wing according to either of claims 1 or 2, characterized in that: The power input unit transmits the power of the engine to the flat cruising power clutch and the vertical suspension power clutch through the double-ended transmission, and the two output ends of the double-ended transmission have different transmission ratios.

4. A tiltrotor STOL fixed wing according to claim 1, characterized in that: The flat cruising power clutch is connected with the flat cruising propeller base when the aircraft is flat cruising, the flat cruising variable-pitch device controls the flat cruising propeller to unfold, the power input of the flat cruising propeller is in a connected state, and the flat cruising propeller rotates and works; When the aircraft is vertically taking off and landing and hovering, the flat cruising power clutch is separated from the flat cruising propeller base, the flat cruising variable-pitch device controls the flat cruising propeller to fold, the power input of the flat cruising propeller is in a disconnected state, and the flat cruising propeller is folded away from the clutch and stops rotating.

5. A tiltrotor STOL fixed wing according to claim 1, characterized in that: The vertical hovering power clutch is connected with the vertical hovering propeller base when the aircraft is in vertical take-off and landing and hovering, the vertical hovering variable pitch device controls the vertical hovering propeller to expand, the power input of the vertical hovering propeller is in the connection state, and the vertical hovering propeller rotates to generate lift; when the aircraft is converted into flat flight cruising, the vertical hovering power clutch is separated from the vertical hovering propeller base, the vertical hovering variable pitch device controls the vertical hovering propeller to be retracted, the power input of the vertical hovering propeller is in the disconnection state, the vertical hovering propeller is retracted to the direction away from the clutch and stops rotating.

6. A tiltrotor STOL fixed wing according to claim 1, wherein: The flat flight cruising power clutch and the vertical hovering power clutch are connected and disconnected under the action control of the flat flight cruising variable pitch device and the vertical hovering variable pitch device.

7. A tiltrotor STOL fixed wing according to claim 1, wherein: The vertical take-off support foot stand and the taxiing landing gear are further included, the vertical take-off support foot stand is installed in the direction of the tail of the fuselage, the taxiing landing gear is started in the aircraft taxiing and landing, is retracted in other working states, and the vertical take-off support foot stand is expanded in the vertical take-off or hovering working state of the aircraft.

Images