A folding wingtip based on an electrically driven actuator, a folding method and an aircraft

Abstract

The present application relates to a kind of folding wing tip based on electric drive actuator, folding method and aircraft, including wing tip fixed end, wing tip movable end and electric drive actuator, wing tip movable end and wing tip fixed end all include upper surface and separation surface, folding rotation axis is arranged at the junction of the upper surface of two, wing tip movable end is rotatably connected with the wing tip fixed end by the folding rotation axis;Actuator is fixed in the wing tip fixed end and wing tip movable end, for pushing wing tip movable end relative to wing tip fixed end rotates certain angle.The track of the actuator of the present application is the design of circular arc guide rail, is set on the upper surface of wing tip to reach the driving efficiency as far as possible, can maximize the actuator force arm, effectively avoid the shortcoming that the driver force arm is shorter in the wing tip folding design of current rotary motor drive, to reduce the requirement to the maximum output torque of electric driver, so that the choice of direct current motor and gear transmission has greater space.

Description

Technical Field

[0001] This invention belongs to the field of aircraft wingtip technology, specifically relating to a folding wingtip based on an electric actuator, a folding method, and an aircraft. Background Technology

[0002] In recent years, the adoption of large-wingspan folding wing designs in the design of large wide-body passenger aircraft has received increasing attention. This design can maximize the increase in the aircraft's lift-to-drag ratio by increasing the wing aspect ratio, thereby reducing fuel consumption, while simultaneously meeting the aircraft's adaptability requirements for airport runways, taxiways, and parking spaces. Currently, folding wingtips have been successfully applied to a certain large passenger aircraft, and it is expected that folding wing technology will be increasingly used in large passenger aircraft in the future.

[0003] Whether hydraulically or electrically driven, extreme crosswind conditions are a primary design consideration in folding wing designs. When the wingtip is raised, under severe crosswind loads, the actuator needs to provide a sufficiently large torque to counteract the extreme torque caused by the severe crosswind on the folding hinge axis. Due to the limited space at the wingtip, the actuator size cannot be large, yet high power output is required. This obviously places high demands on the actuator's performance, especially when the wing is flat, where the design faces even greater challenges due to the actuator's power output limitations. The currently widely discussed extended short-beam folding method based on linear hydraulic actuators provides a relatively small lever arm to counteract extreme external torques, meaning that the same external torque requires the actuator to provide a large thrust or pull output. Current electric motor-driven folding methods, with their folding rotation axis located at the centerline of the wing thickness, have a relatively smaller rotation lever arm. This places more stringent requirements on the motor's power output and the gear ratio of the transmission, posing even greater challenges for large wingspan folding designs. Furthermore, current short-beam hydraulic drive systems also suffer from compressive stability issues under extreme crosswind loads due to the large extension of the actuator cylinder. Existing electric drive systems are also complex in design and inconvenient for maintenance and repair. In addition, current electric drive designs place greater demands on the locking mechanism because the upper and lower wing surfaces are disconnected at the folding point. Summary of the Invention

[0004] In order to overcome the above-mentioned problems in the prior art, the present invention provides a folding wing tip and aircraft based on actuators to solve the above-mentioned problems in the prior art.

[0005] A folding wingtip based on an electrically driven actuator for an aircraft includes a fixed wingtip end, a movable wingtip end, and an actuator.

[0006] The movable end and the fixed end of the wingtip both include an upper wing surface and a separation surface. A folding rotation shaft is provided at the junction of the upper wing surface of the fixed end and the upper wing surface of the movable end of the wingtip. The movable end of the wingtip is rotatably connected to the fixed end of the wingtip through the folding rotation shaft.

[0007] The actuator is simultaneously fixed to the fixed end of the wingtip and the movable end of the wingtip, and is used to push the movable end of the wingtip to rotate a certain angle relative to the fixed end of the wingtip.

[0008] In addition to the aspects described above and any possible implementations, a further implementation is provided in which the angle between the upper wing surface of the fixed end or movable end of the wingtip and the separation surface is between 0 and 180°.

[0009] In addition to the aspects described above and any possible implementations, a further implementation is provided in which the actuator is driven by a motor.

[0010] In addition to the aspects described above and any possible implementations, a further implementation is provided in which the actuator includes an arc-shaped rack track, a slide rail, and a gear assembly, the slide rail being disposed in the middle portion of the arc-shaped rack track, and the gear assembly being disposed on the slide rail.

[0011] In addition to the aspects and any possible implementations described above, a further implementation is provided in which the arc-shaped rack track includes an upper rack track and a lower rack track arranged in parallel, the lengths of which are proportional to the folding angle of the wingtip movable end.

[0012] In addition to the aspects described above and any possible implementations, a further implementation is provided in which the gear assembly includes a driving wheel assembly and a driven wheel assembly.

[0013] In addition to the aspects described above and any possible implementations, a further implementation is provided in which the drive wheel assembly includes a drive wheel, a drive motor, and a drive shaft, the drive motor being connected to the drive wheel via the drive shaft.

[0014] In addition to the aspects described above and any possible implementations, a further implementation is provided in which the driven wheel assembly includes two driven wheels, the driving wheel being engaged with each driven wheel, and the two driven wheels being connected by a hinge.

[0015] In addition to the aspects described above and any possible implementation, a further implementation is provided in which the tooth pitch of the driving wheel, each driven wheel, and the upper and lower rack tracks is the same.

[0016] In addition to the aspects and any possible implementations described above, a further implementation is provided in which the arc-shaped guard plate is fixed to the outer edge of the circular rack track.

[0017] In addition to the aspects and any possible implementations described above, a further implementation is provided in which the arc-shaped rack and pinion track, the arc-shaped slide rail, and the arc-shaped guard plate are all arranged with the folding wing tip rotation axis as the center.

[0018] The present invention also provides a folding method for folding wingtips based on actuators, the method comprising the steps of:

[0019] S1. When the electric drive actuator is turned on, the connection between the fixed end and the movable end of the wingtip at the separation surface is automatically opened, and the lock of the drive gear and the gear set composed of two driven gears of the electric drive actuator is automatically removed.

[0020] S2. The gear set starts moving from one end of the rack track. The motor of the electric drive actuator fixed at the movable end drives the drive shaft of the electric drive actuator fixed at the movable end to rotate. The drive shaft then drives the drive wheel fixed to it to rotate. Then the drive gear drives the upper rack track to move through the meshing of the rack. At the same time, it drives the lower rack track to move in the same direction and at the same speed as the upper rack track through the two driven gears meshing with the drive gear.

[0021] S3. The gear set moves from one end of the rack track to the other end, thereby driving the wingtip movable end to rotate from the initial position to the upright position, so that the wingtip movable end is in the upright state.

[0022] The present invention also provides an aircraft comprising actuator-based folding wingtips.

[0023] Beneficial effects of the present invention

[0024] Compared with the prior art, the present invention has the following beneficial effects: The folding wingtip of the actuator of the present invention includes a fixed end, a movable end, and an actuator. Both the movable end and the fixed end include an upper wing surface and a separation surface. A folding rotation shaft is provided at the junction of the upper wing surface of the fixed end and the upper wing surface of the movable end. The movable end is rotatably connected to the fixed end via this folding rotation shaft. The actuator is fixed to the fixed end and the movable end and is used to push the movable end to rotate relative to the fixed end by a certain angle. The actuator of the present invention uses an arc-shaped guide rail design, located on one side of the lower wing surface to achieve the maximum possible driving efficiency. This design maximizes the actuator lever arm, effectively avoiding the short lever arm of the actuator in current rotary motor-driven wingtip folding designs, thereby reducing the requirement for the maximum output torque of the electric actuator and allowing for greater flexibility in the selection of DC motors and gear transmissions. Furthermore, compared with existing motor drive technologies, this invention is simpler in terms of mechanism and structure, which not only helps to improve structural design efficiency, but also facilitates manufacturing and maintenance. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the electrically driven wingtip folding structure of the present invention;

[0026] Figure 2 This is a schematic diagram of the folding scheme based on the arc-shaped rack and pinion guide rail driven by the motor of the present invention - the oblique separation surface (initial state);

[0027] Figure 3 This is a schematic diagram of the folding scheme based on the arc-shaped rack and pinion guide rail driven by the motor of the present invention - oblique separation surface (intermediate state);

[0028] Figure 4 This is a schematic diagram of the folding scheme based on the arc-shaped rack and pinion guide rail driven by the motor of the present invention - the oblique separation surface (vertical state);

[0029] Figure 5 This is a top view of the initial state of the folding embodiment of the present invention based on a motor driven by an arc-shaped rack and pinion guide rail - oblique separation surface;

[0030] Figure 6 This is a schematic diagram of the right-angle separation surface (initial state) of a folding embodiment based on a circular arc rack and pinion guide rail driven by a motor according to the present invention;

[0031] Figure 7 This is a schematic diagram of a folding embodiment (most probable geometric interference state) in which the hydraulic actuator of the present invention is driven at the moving end of the wingtip. Detailed Implementation

[0032] To better understand the technical solution of this invention, the content of this invention includes, but is not limited to, the specific embodiments described below. Similar technologies and methods should be considered within the scope of protection of this invention. To make the technical problems to be solved, the technical solutions, and advantages of this invention clearer, a detailed description will be provided below in conjunction with the accompanying drawings and specific embodiments.

[0033] It should be understood that the embodiments described in this invention are merely some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention.

[0034] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” as used in the embodiments of this invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0035] like Figure 1 As shown, the actuator-based folding wingtip of the present invention, used in an aircraft, includes a fixed wingtip end 2, a movable wingtip end 1, and an actuator 3.

[0036] The movable end 1 and the fixed end 2 of the wingtip both include an upper wing surface, a lower wing surface and a separation surface 6. A folding rotation shaft 8 is provided at the junction of the upper wing surface of the fixed end 2 and the movable end 1. The movable end 1 of the wingtip is rotatably connected to the fixed end 2 of the wingtip through the folding rotation shaft 8.

[0037] The actuator 3 is fixed to both the fixed end 2 and the movable end 1 of the wingtip, and is used to push the movable end 1 of the wingtip to rotate a certain angle relative to the fixed end 2 of the wingtip.

[0038] Furthermore, the angle between the upper wing surface of the fixed end 2 or the movable end 1 of the wingtip and the separation surface is between 0 and 180°, excluding 0° and 180°.

[0039] Furthermore, the actuator 3 is motor-driven or electrically driven, such as... Figure 2As shown, the actuator 3 includes an arc-shaped rack track, a groove or slide rail 7, and a gear assembly. The groove or slide rail 7 is located in the middle part of the arc-shaped rack track, and the gear assembly is located on the slide rail. The arc-shaped rack track includes an upper rack track and a lower rack track 4 arranged in parallel. The length of the upper and lower rack tracks is proportional to the folding angle of the wingtip movable end 1. That is, the longer the arc length of the upper and lower rack tracks, the larger the folding angle of the wingtip movable end 1, and vice versa. The setting is determined according to the actual situation. The gear assembly includes a driving wheel assembly and a driven wheel assembly. The driving wheel assembly includes a driving wheel, a drive motor 5, and a drive shaft 51. The drive motor 5 is connected to the driving wheel through the drive shaft 51. The driving wheel meshes with the upper rack track, and the two driven wheels mesh with the lower rack track. The curvature centers of the upper and lower rack tracks are coaxial with the wingtip folding rotation axis 8.

[0040] like Figure 2 and Figure 5 As shown, one end of the arc-shaped rack track is fixed to the wingtip fixed end 2, and the other end, the extended end, is also fixed to the fixed end 2 via a bracket 10 or an extended web. The extended web can be a direct extension of the beam web of the wingtip fixed end 2, or it can be indirectly connected to the beam web of the wingtip fixed end 2 via an intermediate member capable of transmitting bending, shear, and torsional loads. The extended webs are fixed laterally via corner plates using partitions or brackets, forming a box-section extended structure capable of transmitting bending, shear, and torsional loads. This extended structure can also be made into a rigid frame form according to specific structural requirements, directly connecting its two ends to the wing beam of the wingtip fixed end 2 or an intermediate transition structure connected to the wing beam via bolts. Similarly, if the arc-shaped rack track is fixed to the wingtip movable end 1, the drive assembly 14, consisting of the drive shaft 51 and the drive motor 5, is fixed to the wingtip fixed end 2. The wingtip movable end 1 rotates around the folding rotation axis 8 through the mutual pushing between the master and slave gear sets and the rack track.

[0041] Furthermore, the folding rotation axis 8 is located on one side of the upper wing surface of the movable end 1 of the wing tip, while the arc-shaped rack and pinion track is as close as possible to the opposite side, namely the lower wing surface. This arrangement maximizes the driving force lever arm, that is, the vertical distance from the upper and lower rack and pinion tracks to the folding rotation axis 8, which is also the radius of the arc track, is as large as possible. This radius is the driving force lever arm, thereby improving the motor drive efficiency. At the same time, the lever arm remains constant throughout the folding process, which is convenient for analysis and control.

[0042] The driving gear and the two driven gears below it form a gear set. The tooth spacing on the driving gear, driven gears, and the upper and lower rack tracks is the same. Thus, when the driving gear is driven, it can not only drive the upper rack track but also drive the lower rack track to move at the same speed and in the same direction via the driven gears. Simultaneously, the entire gear set can rotate around the driving shaft 51 of the driving gear. Alternatively, depending on the rack design requirements, more driven gears can be connected in series in a sawtooth-shaped zigzag pattern between the upper and lower gears, i.e., increasing the number of gear sets. This results in more gears driving the upper and lower rack tracks to move in the same direction, thereby reducing the force borne by each rack.

[0043] The upper and lower rack tracks are fixed to the vertical web plate 11 of the wingtip fixed end 1 by means of bolts and adhesive, thereby connecting and fixing them to the wingtip fixed end 1. The web plate 11 is provided with a groove or slide rail 7 to bear the force applied by the upper and lower rack tracks to the driving wheel and the driven wheel, which is perpendicular to the driving wheel drive shaft 51. In this way, the driving wheel drive shaft 51 can only bear the torque load. In addition, the curvature center of the groove is also coaxial with the wingtip folding rotation hinge shaft 8. The upper and lower rack tracks are fixed to the fixed end 2 by the vertical web plate 11 or rigid frame extending from the wingtip fixed end and the outer end bracket 10, while the drive motor 5 and the driving wheel drive shaft 51 are fixed to the wingtip movable end 1. The drive shaft 51 is fixed by the vertical web plate or rigid frame 12 of the wingtip movable end 1. Driven by the motor 5, the gear set pushes the movable end 1 to rotate around the folding rotation shaft 8 at the driving wheel drive shaft 51 through the upper and lower rack tracks fixed to the fixed end 2. Figure 5 In the diagram, A and B represent the starting position of the drive shaft 51 when it is retracted and the final position when it is erected at the movable end 1 of the wing tip, respectively. They also correspond to the two ends of the gear track or slide rail. In this invention, the gearbox and the motor are fixed together and coaxially connected.

[0044] Furthermore, the present invention includes an arc-shaped protective plate 9 fixed to the outer edge of the upper and lower rack tracks. The center of curvature of the protective plate 9 is the same as that of the upper and lower rack tracks, both being the wingtip folding rotation hinge axis o. The arc-shaped rack tracks, the arc-shaped slide rails, and the arc-shaped protective plate are all arranged with the folding wingtip rotation axis as the center. This minimizes the mutual interference that may occur between the protective plate 9 and the wingtip movable end 1 during the entire rotation process. When the wingtip movable end 1 is in the upright position after the aircraft lands, this protective plate 9 provides protection for the aircraft's internal systems against external environmental factors such as dust, sand, and ultraviolet radiation.

[0045] Furthermore, the movable end 1 and the fixed end 2 of the wingtip of the present invention are connected to each other by a hinge along the wingtip folding and rotating hinge shaft 8. The lower wing surfaces of the fixed end and the movable end can be automatically opened and closed and locked at the separation surface by multiple lugs 13 and pins that cooperate with the lugs. In addition, by means of the blocking of the driving wheel and the outermost driven wheel by the vertical side plates at the ends of the upper and lower rack tracks and the blocking of the drive shaft by the end of the slide groove, the movable end of the wingtip is constrained from continuing to rotate. At the same time, by simply locking the gear set, such as on the inner side of the gear set, that is, on the side farther from the end of the gear track, the gear set is blocked from retracting by an automatically falling wedge between the driving wheel and the driven wheel. In this way, since the drive shaft cannot move forward or backward relative to the gear track, the wingtip fixedly connected to it cannot rotate forward or backward, that is, it is completely locked. In other words, when the wingtip is retracted, in addition to the movable end 1 and the fixed end 2 being locked at the lower wing surface separation surface by the lugs and the pivot pin, the internal folding mechanism of the wingtip can also provide additional locking, thus further ensuring that the wingtip will not suddenly fold in the air due to the opening of the lower wing surface caused by the failure of a single locking mechanism during the flight of the aircraft.

[0046] Furthermore, the separation surface of the movable end 1 of the wing tip and the separation surface of the fixed end 2 of the present invention are set as an oblique plane or a right-angled plane.

[0047] Furthermore, the angle between the two ends of the upper and lower arc-shaped rack track of the present invention and the folding rotation axis o is the rotatable angle of the folding wingtip. Therefore, the present invention can not only achieve 90° folding of the wingtip, but also achieve folding of any large angle greater than 90° by increasing the length of the rack track.

[0048] Figure 2 , Figure 3 and Figure 4 The invention presents the initial, intermediate, and upright states of the folding scheme when the separation plane angle is 45° and the maximum folding angle of the wingtip is 90°. In this invention, the motor, drive gear shaft, and movable wingtip drive point—the folding rotation axis O—are all on a single axis, supported at both ends by a rack and pinion track, resulting in good stability. Furthermore, the invention incorporates a protective plate for automatic protection; therefore, the wingtip structure is simple, the driving force lever arm is large, which is beneficial for improving motor efficiency. In addition, the lever arm remains constant during folding, simplifying the design.

[0049] To provide a better protective appearance to the open area around the folding pivot after folding. Figure 6 A further example based on a right-angled separation surface is given. To avoid interference, the upper and lower arc-shaped rack guides are rotated counterclockwise by a small angle, such as about 15°, so that the end position of the gear set is slightly lower than the position of the upper wing surface. Figure 7The figure shows the state of the open area around the folding rotation axis after the wingtip is erected and the automatically implemented protective plate design. As can be seen from the figure, this design has a better smooth appearance and can also reduce the damage to the wingtip structure caused by possible scratches from foreign objects.

[0050] As a disclosed embodiment, the present invention also provides a folding method for folding wing tips, comprising the following steps: S1. When the electric drive actuator is turned on, the connection between the fixed end of the wing tip and the movable end of the wing tip at the separation surface is automatically opened, and the lock of the gear set consisting of the driving gear and the two driven gears of the electric drive actuator is automatically removed.

[0051] S2. The gear set starts moving from one end of the rack track. The motor of the electric drive actuator fixed at the movable end drives the drive shaft of the electric drive actuator fixed at the movable end to rotate. The drive shaft then drives the drive wheel fixed to it to rotate. Then the drive gear drives the upper rack track to move through the meshing of the rack. At the same time, it drives the lower rack track to move in the same direction and at the same speed as the upper rack track through the two driven gears meshing with the drive gear.

[0052] S3. The gear set moves from one end of the rack track to the other end, thereby driving the wingtip movable end to rotate from the initial position to the upright position, so that the wingtip movable end is in the upright state.

[0053] Specifically, the folding process of the present invention is as follows: when the actuator is in the initial state (e.g. Figure 2 (As shown) After opening, the lug connection between the fixed end 2 and the movable end 1 at the lower wing surface automatically opens, and the lock of the gear set is automatically removed. Then, the motor fixed to the movable end 1 drives the drive shaft 51 fixed to the movable end 1 to rotate. The drive shaft 51 then drives the drive gear fixed to it to rotate. Then, the drive gear, through the meshing of the rack, drives the upper rack track to move on one hand, and also drives the lower rack track to move in the same direction and at the same speed as the upper rack track through the two driven gears. Since the drive shaft 51 is fixed to the movable end 1, and the upper and lower rack tracks are fixed to the fixed end 2, the relative movement between the drive shaft 51, that is, the gear set and the upper and lower rack tracks, drives the entire movable end 1 to rotate around the rotation axis o of the upper wing surface. When the gear set moves from the initial end A to the center position of the rack track, the movable end 1 of the wingtip has rotated to half of its stroke (e.g., Figure 3 As shown). When the motor-driven gear set continues to move to the other end B of the gear track, the entire movable end 1 completes its rotation, thus reaching the upright position (as shown). Figure 4(As shown). Afterwards, the gear is locked, the motor is turned off, and the wingtip is erected, capable of withstanding various loads, especially lateral wind loads. When the wingtip movable end 1 is to be retracted, the motor is started in reverse, and the gear lock is released simultaneously. As mentioned earlier, the motor then drives the drive gear and driven gear through the drive shaft, causing the upper and lower rack tracks to move from end B to end A. The direction of movement is opposite to the direction of movement during the erection of the movable end 1. When the gear set is at end A of the actuator, the wingtip movable end 1 is in its initial flat position, and the separation surfaces of the movable end 1 and the fixed end 2 are completely closed. Then, the gear is locked, and the lug connection at the separation surface of the lower wing surface is locked. The motor is turned off, completing the retracted state.

[0054] As a disclosed embodiment, the present invention also provides an aircraft including actuator-based folding wingtips.

[0055] The foregoing description illustrates and describes several preferred embodiments of the present invention. However, as previously stated, it should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the inventive concept described herein through the foregoing teachings or techniques or knowledge in related fields. Any modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.

Claims

1. A folding wingtip based on an electric actuator for an aircraft, characterized in that, Includes the fixed wingtip end, the movable wingtip end, and the electric drive actuator. The wingtip movable end and the wingtip fixed end both include an upper wing surface and a separation surface. A folding rotation shaft is provided at the junction of the upper wing surface of the fixed end and the upper wing surface of the wingtip movable end. The wingtip movable end is rotatably connected to the wingtip fixed end through the folding rotation shaft. The electric drive actuator includes an arc-shaped rack and pinion track, a slide rail, and a gear assembly. The slide rail is disposed in the middle part of the arc-shaped rack and pinion track, and the gear assembly is disposed on the slide rail. The arc-shaped rack track includes an upper rack track and a lower rack track arranged in parallel, and the length of the upper and lower rack tracks is proportional to the folding angle of the movable end of the wingtip; The gear assembly includes a driving wheel assembly and a driven wheel assembly. The driving wheel assembly includes a driving wheel, a drive motor, and a drive shaft. The drive motor is connected to the driving wheel via the drive shaft. The driving wheel meshes with the upper rack track. The two driven wheels mesh with the lower rack track, and the two driven wheels are connected by hinges. The curvature centers of the upper and lower rack tracks are coaxial with the wingtip folding rotation axis. The electric drive actuator is fixed to both the fixed end and the movable end of the wingtip, and is used to drive the movable end of the wingtip to rotate a certain angle relative to the fixed end of the wingtip.

2. The folding wingtip based on an electric drive actuator according to claim 1, characterized in that, The angle between the upper wing surface of the fixed end or movable end of the wingtip and the separation surface is between 0 and 180°.

3. The folding wingtip based on an electric drive actuator according to claim 1, characterized in that, The tooth spacing of the driving wheel, each driven wheel, and the upper and lower rack tracks is the same.

4. A folding method for folding wingtips based on an electrically driven actuator, characterized in that, The method is implemented using the folding wingtip as described in any one of claims 1-3, and includes the following steps: S1. When the electric drive actuator is turned on, the connection between the fixed end and the movable end of the wingtip at the separation surface is automatically opened, and the lock of the drive gear and the gear set composed of two driven gears of the electric drive actuator is automatically removed. S2. The gear set starts moving from one end of the rack track. The motor of the electric drive actuator fixed at the movable end drives the drive shaft of the electric drive actuator fixed at the movable end to rotate. The drive shaft then drives the drive wheel fixed to it to rotate. Then the drive gear drives the upper rack track to move through the meshing of the rack. At the same time, it drives the lower rack track to move in the same direction and at the same speed as the upper rack track through the two driven gears meshing with the drive gear. S3. The gear set moves from one end of the rack track to the other end, thereby driving the wingtip movable end to rotate from the initial position to the upright position, so that the wingtip movable end is in the upright state.

5. An aircraft, characterized in that, The aircraft includes folding wingtips based on electric actuators as described in any one of claims 1-3.

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