Tilting folding wing and vertical take-off and landing aircraft

Abstract

The invention discloses a tilting folding wing and a vertical take-off and landing aircraft. Comprising a central wing (2), outer wings (3) capable of being folded / unfolded in a tilting mode are symmetrically connected to the two ends of the central wing (2), and tilting rotating shafts (501) of the outer wings (3) are located at the outer ends of the central wing (2) and located at the positions, close to the rear portions, of the front edges of the outer wings (3); the two outer wings are driven by the same folding driving mechanism (4) to be folded / unfolded in a tilting mode, and the connecting line of points on the outer wings (3) before and after tilting is perpendicular to the rotating shaft (501). The device has the advantages of being simple in structure, good in synchronism and high in safety.

Description

Technical Field

[0001] The invention belongs to the technical field of aircraft design, and in particular relates to a tilt-folding wing and a vertical take-off and landing aircraft. Background Art

[0002] With the continuous development of current vertical take-off and landing aircraft technology, vertical take-off and landing aircraft that combine the vertical take-off and landing capabilities of rotorcraft with the long flight time and long range characteristics of fixed-wing aircraft have emerged. The wing structure generally adopts fixed wings or composite wings. However, due to the large wingspan, this type of aircraft often occupies too much space during storage and transportation, and sometimes the wings need to be disassembled and reassembled, which increases the cost of using the aircraft. In view of the problem that the application of existing vertical take-off and landing aircraft technology in remote towns, uninhabited areas, islands and other areas with inconvenient transportation environments is hindered, as well as the low flight efficiency of fixed-wing mode in vertical take-off and landing state, and the difficulty in switching between vertical take-off and landing mode and fixed-wing forward flight mode, some researchers have proposed using folding wings to replace the entire wing, so that the aircraft can cope with storage and transportation on the ground in a folded state. After take-off, the wing switches to the unfolded and locked state, increasing the wing area to obtain higher lift, retaining the advantage of long range under the condition of small landing space, and greatly broadening the use scenarios of the aircraft.

[0003] Most of the wing folding, unfolding and locking mechanisms under current technology have the defect of complex structure. Generally, two sets of folding drive mechanisms drive different wings on both sides respectively. There are many parts, which occupy a large amount of internal space of the aircraft and increase unnecessary weight. At the same time, this configuration is also prone to cause differences in the motion states of the wings on both sides, poor motion synchronization, and low safety. Summary of the invention

[0004] The purpose of the present invention is to provide a tilting and folding wing and a vertical take-off and landing aircraft. The present invention has the characteristics of simple structure, good synchronization and high safety.

[0005] The technical solution of the present invention is: a tilt-folding wing, comprising a central wing, with outer wings that can be tilted, folded / unfolded being symmetrically connected at both ends of the central wing, and the rotation axis for tilting the outer wings being located at the outer end of the central wing and behind the leading edge of the outer wings; the two outer wings are driven to tilt, fold / unfold by the same folding drive mechanism, and the line connecting the points on the outer wings before and after the tilting is perpendicular to the rotation axis.

[0006] In the aforementioned tilt-folding wing, the rotation axis is determined based on the following method: a coordinate system is constructed based on the leading edge point O of the inner end of the outer wing, with the heading as the x-axis, the span as the y-axis, and the vertical as the z-axis. The direction vector of the rotation axis is set as (a, b, c), and the tilt-folding angle is θ; then:

[0007]

[0008] In the aforementioned tilt-folding wing, the tilt-folding angle θ is 70°.

[0009] In the aforementioned tilt-folding wing, the folding drive mechanism includes a bracket located on the symmetry axis of the two outer wings, a lead screw is rotatably connected to the bracket, the lead screw body is connected to the sliding rod via a lead screw nut, both ends of the sliding rod are movably connected to one end of a pull rod respectively, and the other ends of the two pull rods are connected to the corresponding outer wings via spherical hinges respectively; when the outer wings tilt, the spherical hinge rotates around the rotation axis; one end of the lead screw is connected to the driving motor.

[0010] In the aforementioned tilt-folding wing, a brake is provided at the other end of the lead screw.

[0011] In the aforementioned tilt-folding wing, a guide rail slider is provided on the slide rod, and the guide rail slider is slidably connected to a guide rail provided on the bracket.

[0012] In the aforementioned tilt-folding wing, a straight line passing through the trailing edge point M of the inner end surface of the outer wing and intersecting the rotation axis is taken as a generatrix; the generatrix is ​​swept around the rotation axis to form a rotation curved surface; the outer end surface of the central wing is filled with the rotation curved surface separation surface, and the inner end surface of the outer wing is trimmed to obtain the matching surface between the outer end surface of the central wing and the inner end surface of the outer wing during tilting.

[0013] In the aforementioned tilt-folding wing, the hinge point of the spherical hinge and the tie rod is located in the extended area of ​​the inner end surface of the outer wing. When the outer wing is unfolded, the hinge point is located behind the rotation axis, and when the outer wing is folded, the hinge point is located in front of the rotation axis.

[0014] In the aforementioned tilt-folding wing, when the outer wing is folded, the bottom surface of the outer wing is in an outward-turned state.

[0015] A vertical take-off and landing aircraft constructed with the aforementioned tilt-folding wing comprises a fuselage, a central wing is arranged on the fuselage, and a folding drive mechanism is fixed to the fuselage.

[0016] The advantages of the present invention are:

[0017] Traditional fixed-wing or composite-wing aircraft occupy a large space; the present invention constrains the double-sided wings through the tilted rotating shaft, and uses the lead screw slide rail mechanism to realize the tilting and folding of the wings, thereby solving the technical problem of needing to disassemble and reassemble the wings during storage and transportation;

[0018] Most of the existing aircraft wing folding mechanisms have two sets of independent drive mechanisms on both sides, which require coordinated control of multiple motors. The present invention places the drive motor on the center line of the aircraft to synchronously drive the outer wings on both sides to complete the folding action, thereby solving the problems of complex configuration, high control difficulty, poor synchronization and low safety of the folding wings of traditional aircraft.

[0019] The existing vertical take-off and landing aircraft technology has the problem that the fixed-wing mode flight efficiency is low in the vertical take-off and landing state. The present invention cleverly combines the tilting and folding movements by tilting the rotation axis. The outer wing has a small windward area after tilting and folding in the vertical take-off and landing state, which solves the problem that the vertical take-off and landing flight efficiency of traditional aircraft is difficult to improve.

[0020] The folding drive mechanism for wing tilting of the present invention has a simple structure, few mechanism parts, small space occupation, light weight, and is easy to implement and maintain;

[0021] The present invention uses a single motor to synchronously drive the tilting and folding movement of the wings on both sides of the vertical take-off and landing aircraft, which has low control difficulty and good synchronization, and enhances the controllability and safety of the aircraft;

[0022] The present invention skillfully combines the tilting and folding motions by tilting the rotation axis. The folding motion can satisfy the requirement of transmitting motion and load in an area with a small structural space, and the tilting motion improves the flight efficiency of the aircraft in the vertical take-off and landing state.

[0023] The present invention ensures the integrity of the wing airfoil in the unfolded state through the separation surface design, thereby ensuring the flight efficiency of the aircraft in the forward flight state. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a top view of the vertical take-off and landing aircraft with its wings tilted and folded;

[0025] Figure 2 It is a schematic diagram of the solution of the rotation axis;

[0026] Figure 3 is a schematic diagram of the connection between the folding drive mechanism and the outer wing;

[0027] Figure 4 It is a top view schematic diagram of the wing separation surface design;

[0028] Figure 5 It is a schematic diagram of the outer wing folding-unfolding state;

[0029] Figure 6 It is a three-dimensional schematic diagram of the wing folding state of the vertical take-off and landing aircraft;

[0030] Figure 7 It is a three-dimensional schematic diagram of the wing of a vertical take-off and landing aircraft in an unfolded state;

[0031] Figure 8 is a schematic diagram of a vertical take-off and landing aircraft with its wings deployed, viewed from above;

[0032] Fig. 9 It is a schematic diagram of a vertical take-off and landing aircraft with its wings folded as seen from above. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0034] The features and illustrative embodiments of various aspects of the present invention will be described in detail below. In the detailed description below, many specific details are proposed to provide a comprehensive understanding of the present invention. However, it is obvious to those skilled in the art that the present invention can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present invention by illustrating examples of the present invention. The present invention is by no means limited to any specific settings and methods proposed below, but covers any improvements, replacements and modifications of structures, methods, devices without departing from the spirit of the present invention. In the accompanying drawings and the following description, known structures and technologies are not shown to avoid unnecessary ambiguity in the present invention.

[0035] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other, and the embodiments can refer to and quote each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0036] Example 1. A tilt-folding wing, see Figure 1-Figure 9 , including a central wing 2, with outer wings 3 that can be tilted, folded / unfolded symmetrically connected at both ends of the central wing 2, and a rotation axis 501 for tilting the outer wings 3 is located at the outer end of the central wing 2 and behind the front edge of the outer wings 3; the two outer wings are driven to tilt, fold / unfold by the same folding drive mechanism 4, and the line connecting the points on the outer wings 3 before and after the tilting is perpendicular to the rotation axis 501.

[0037] The aforementioned rotation axis 501 is determined based on the following method: a coordinate system is constructed based on the leading edge point O of the inner end of the outer wing 3, with the heading as the x-axis, the span direction as the y-axis, and the vertical direction as the z-axis. The direction vector of the rotation axis 501 is set to (a, b, c), and the tilt folding angle is θ; see Figure 2 , Figure 2 In the equation, M is the trailing edge point of the inner end surface of the outer wing 3 when unfolded, M' is the trailing edge point of the inner end surface of the outer wing 3 when folded, N is the trailing edge point of the outer end surface of the outer wing 3 when unfolded, N' is the trailing edge point of the outer end surface of the outer wing 3 when folded, Q is the leading edge point of the outer end surface of the outer wing 3 when unfolded, and Q' is the leading edge point of the outer end surface of the outer wing 3 when folded; then: the direction vector of the line MM' and NN' is:

[0038] MM=(-1,0,1)

[0039] NN′=(2sinθ-1,2cosθ-2,-1)

[0040] Then we have:

[0041]

[0042] but:

[0043]

[0044] The tilt folding angle θ is 70°. When θ=70°, the rotation axis direction vector is (1, 1.4281, -1).

[0045] The aforementioned folding drive mechanism 4 includes a bracket 401 located on the symmetry axis of the two outer wings 3, and a lead screw 404 is rotatably connected to the bracket 401. The lead screw 404 is connected to the slide rod 408 via a lead screw nut 406, and both ends of the slide rod 408 are movably connected to one end of a pull rod 410 respectively, and the other ends of the two pull rods 410 are connected to the corresponding outer wings 3 via ball hinges 411 respectively; when the outer wings 3 tilt, the ball hinge 411 rotates around the rotation axis 501; one end of the lead screw 404 is connected to the drive motor 402 via a coupling 403.

[0046] The other end of the lead screw 404 is provided with a brake 409 .

[0047] The aforementioned slide bar 408 is provided with a guide rail slider 407 , and the guide rail slider 407 is slidably connected to a guide rail 405 provided on the bracket 401 .

[0048] A straight line passing through the trailing edge point M of the inner end surface of the outer wing 3 and intersecting the rotation axis 501 is taken as a generatrix 502; the generatrix 502 is swept around the rotation axis 501 to form a rotation curved surface 503; the outer end surface of the central wing 2 is filled with a separation surface of the rotation curved surface 503, and the inner end surface of the outer wing 3 is trimmed to obtain a matching surface between the outer end surface of the central wing 2 and the inner end surface of the outer wing 3 during tilting.

[0049] The hinge point of the aforementioned spherical hinge 411 and the tie rod 410 is located in the extension area of ​​the inner end surface of the outer wing 3. When the outer wing 3 is unfolded, the hinge point is located behind the rotation axis 501 (see Figure 8 ), when the outer wing 3 is folded, the hinge point is located in front of the rotation axis 501 (see Fig. 9 ).

[0050] When the outer wing 3 is folded, the bottom surface of the outer wing 3 is in an outward-turned state.

[0051] The vertical take-off and landing aircraft of the aforementioned tilt-folding wing structure comprises a fuselage 1 , on which a central wing 2 is arranged, and a folding drive mechanism 4 is fixed to the fuselage 1 .

[0052] like Figure 1 As shown, in the ground preparation for takeoff, the two outer wings 3 are tilted 90° (the outer wings are converted from horizontal / vertical to vertical / horizontal), and at the same time are close to the fuselage 1 at a certain folding angle. When the aircraft rises to a sufficient height, the outer wings 3 are pulled back and forth along the oblique downward direction by the folding drive mechanism 4 to unfold them, and switch to the forward flight mode. The folding angle refers to the angle between the outer wings and the central axis of the fuselage 1 in the folded state.

[0053] The relative movement between the outer wing 3 and the central wing 2 is constrained by an inclined rotation axis 501, and the direction of the rotation axis 501 affects the folding angle of the outer wing 3 relative to the fuselage 1. Figure 1 The demonstration given in the figure is a 70° folding demonstration. The specific folding angle can be adjusted according to the shape of the aircraft and space constraints.

[0054] The relative movement between the outer wing 3 and the central wing 2 is driven by the folding drive mechanism 4. The folding drive mechanism 4 is fixed inside the fuselage 1 through a bracket 401. The motor 402 is fixed on the bracket 401. The motor shaft is connected to the lead screw 404 through a coupling 403. A guide rail 405 is fixed on both sides of the bracket 401. The lead screw nut 406 and two guide rail sliders 407 are fixed to the slide bar 408. The double-sided redundant constraint of the guide rail 405 on the slide bar 408 can reduce the cantilever length and improve the rigidity of the slide bar 408. The two sides of the slide bar 408 are connected to the pull rod 410 through a spherical hinge 411, and the other end of the pull rod 410 is connected to the outer wing 3 through a spherical hinge 411. The other end of the lead screw 404 is connected to a brake 409 fixed to the bracket 401, which is used for braking and locking under extreme conditions.

[0055] In order to ensure sufficient lift in the forward flight state, the separation surface design allows the entire wing to have a complete airfoil after deployment, while ensuring that no collision or interference occurs during the deployment movement. A point on the rotation axis 501 is selected and connected to the farthest point on the wing edge to form a generatrix 502, and the generatrix 502 is swept around the rotation axis 501 to form a rotation surface 503. The rotation surface 503 is used as a separation surface to fill the central wing 2 and trim the outer wing 3. In this way, the two wings will not interfere with each other during the movement and will be merged into a complete airfoil in the deployed state. The curved boundary of the rotation surface 503 is the movement trajectory of the outer wing 3. Since the separation surface is intercepted from a part of the cone surface, it is a single curvature surface, which reduces the manufacturing difficulty for composite parts.

[0056] The present invention cleverly combines the tilting and folding movements by tilting the rotation axis. The folding movement can meet the requirements of transmitting movement and load in a small structural space area, breaking the application environment restrictions of the aircraft. The tilting movement reduces the wing's windward area and improves the flight efficiency of the aircraft in the vertical take-off and landing state. At the same time, the separation surface design ensures the integrity of the wing airfoil in the unfolded state, thereby ensuring the flight efficiency of the aircraft in the forward flight state.

[0057] The present invention uses a single motor to synchronously drive the tilting and folding movements of the wings on both sides, has a simple principle, compact structure, light weight, and low cost, and has the characteristics of being easy to implement and maintain in engineering practice.

[0058] The invention can be applied to vertical take-off and landing aircraft such as KAT type aircraft.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the field can easily think of various equivalent modifications or substitutions within the technical scope disclosed by the present invention, and these modifications or substitutions should all be covered within the protection scope of the present invention.

Claims

1. A tilt-folding wing, characterized in that: The invention comprises a central wing (2), wherein the two ends of the central wing (2) are symmetrically connected with outer wings (3) capable of tilting, folding and unfolding, and the rotation axis (501) for the tilting of the outer wings (3) is located at the outer end of the central wing (2) and behind the front edge of the outer wings (3); the two outer wings are driven to tilt, fold and unfold by the same folding drive mechanism (4), and the line connecting the points on the outer wings (3) before and after the tilting is perpendicular to the rotation axis (501).

2. The tilt-folding wing according to claim 1, characterized in that: The rotation axis (501) is determined based on the following method: a coordinate system is constructed based on the leading edge point O of the inner end of the outer wing (3), with the heading direction as the x-axis, the span direction as the y-axis, and the vertical direction as the z-axis. The direction vector of the rotation axis (501) is assumed to be (a, b, c), and the tilt folding angle is θ; then:

3. The tilt-folding wing according to claim 2, characterized in that: The tilting and folding angle θ is 70°.

4. The tilt-folding wing according to claim 1, characterized in that: The folding drive mechanism (4) includes a bracket (401) located on the symmetry axis of the two outer wings (3), a lead screw (404) is rotatably connected to the bracket (401), the lead screw (404) is connected to the slide rod (408) via a lead screw nut (406), the two ends of the slide rod (408) are respectively movably connected to one end of a pull rod (410), and the other ends of the two pull rods (410) are respectively connected to the corresponding outer wings (3) via spherical hinges (411); when the outer wings (3) are tilted, the spherical hinge (411) rotates around the rotation axis (501); one end of the lead screw (404) is connected to the drive motor (402).

5. The tilt-folding wing according to claim 4, characterized in that: The other end of the lead screw (404) is provided with a brake (409).

6. The tilt-folding wing according to claim 4, characterized in that: The slide bar (408) is provided with a guide rail slider (407), and the guide rail slider (407) is slidably connected to a guide rail (405) provided on the bracket (401).

7. The tilt-folding wing according to claim 1, characterized in that: A straight line passing through the rear edge point M of the inner end surface of the outer wing (3) and intersecting the rotation axis (501) is taken as a generatrix (502); the generatrix (502) is swept around the rotation axis (501) to form a rotation curved surface (503); the outer end surface of the central wing (2) is filled with a separation surface of the rotation curved surface (503), and the inner end surface of the outer wing (3) is trimmed to obtain a matching surface between the outer end surface of the central wing (2) and the inner end surface of the outer wing (3) during tilting.

8. The tilt-folding wing according to claim 1, characterized in that: The hinge point between the spherical hinge (411) and the pull rod (410) is located in the extension area of ​​the inner end surface of the outer wing (3). When the outer wing (3) is unfolded, the hinge point is located behind the rotation axis (501). When the outer wing (3) is folded, the hinge point is located in front of the rotation axis (501).

9. The tilt-folding wing according to claim 1, characterized in that: When the outer wing (3) is folded, the bottom surface of the outer wing (3) is in an outward-turned state.

10. A vertical take-off and landing aircraft having a tilt-folding wing structure according to any one of claims 1 to 9, characterized in that: The invention comprises a fuselage (1), a central wing (2) is arranged on the fuselage (1), and a folding drive mechanism (4) is fixed on the fuselage (1).

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