Main landing gear of electric vertical take-off and landing aircraft

Abstract

The utility model discloses a main landing gear of an electric vertical take-off and landing aircraft, and relates to the technical field of aircrafts. The main undercarriage comprises a main lifting shaft, a main lifting beam, a buffer and an aircraft wheel, the two ends of the main lifting shaft are hinged to the aircraft body through fixing pin shafts, the main lifting shaft can rotate around the axis, the middle of the main lifting shaft and the front end of the main lifting beam are vertically and fixedly welded, and the aircraft wheel is installed at the tail end of the main lifting beam; and the upper end of the buffer is hinged to the machine body. The main landing gear structure provided by the utility model can meet the requirements of bearing and energy absorption when an aircraft lands, and is simple in structural design configuration, low in structural process difficulty, short in manufacturing period, low in manufacturing cost, low in assembly difficulty, easy to maintain, simple and clear in load transmission path and relatively low in structural weight.

Description

Technical Field

[0001] This utility model relates to the field of aircraft, and in particular to a main landing gear for an electric vertical takeoff and landing aircraft. Background Technology

[0002] In recent years, EVTOL (Electric Vertical Take-Off and Landing) aircraft have become the primary urban air mobility solution due to their significant advantages of being environmentally friendly and having low dependence on infrastructure. The landing gear, as a major component of the aircraft, works in conjunction with tires and shock absorbers to reduce the impact force between the aircraft and the ground to a level that the structure can withstand during take-off and landing, ensuring safe take-off and landing.

[0003] Currently, the main landing gear of general aviation aircraft in the 1-2 ton class generally uses steel leaf springs in conjunction with tires to achieve impact resistance and shock absorption. Its structure is relatively simple, capable of withstanding heavy loads, and absorbs impact energy through the elastic deformation of the leaf springs, meeting the needs of safe flight and operation. However, the main landing gear of general aviation aircraft has the following shortcomings:

[0004] ① Leaf springs deform elastically, resulting in low efficiency in absorbing impact energy;

[0005] ② In order to absorb enough energy, the leaf spring needs a large amount of deformation, which means that the leaf spring needs a sufficient length, resulting in a large structural weight.

[0006] ③ Leaf springs have high requirements for the heat treatment and processing technology of steel plate raw materials; otherwise, they may not meet the design specifications.

[0007] ④ After the leaf spring undergoes elastic deformation, the elastic recovery process is very fast, which puts a large overload on the machine body and results in poor passenger comfort.

[0008] Based on this, this utility model proposes an electric vertical takeoff and landing aircraft landing gear that can not only meet the necessary functional and safety requirements, but also has the characteristics of simple configuration, easy manufacturing, strong impact resistance and energy absorption capacity, so as to meet the safety, comfort and economy requirements of long-term aircraft operation. Utility Model Content

[0009] This utility model provides a main landing gear for an electric vertical takeoff and landing aircraft, including: a main landing shaft 21, a main landing beam 22, a buffer 23, and a wheel 24. The two ends of the main landing shaft 21 are hinged to the fuselage 1 through fixed pins 15. The main landing shaft 21 can rotate around its axis. The middle part of the main landing shaft 21 is fixedly welded to the front end of the main landing beam 22 in a perpendicular shape. The wheel 24 is installed at the end of the main landing beam 22. The lower end of the buffer 23 is hinged to the middle part of the main landing beam 22, and the upper end of the buffer 23 is hinged to the fuselage 1.

[0010] As described above, the main landing gear of an electric vertical takeoff and landing aircraft includes a tie rod 25. One end of the tie rod (25) is hinged to the main landing shaft (21), and the other end is hinged to the main landing beam (22). The tie rod 25, together with the main landing shaft 21 and the main landing beam 22, forms a stable triangular structure to jointly bear the load of the aircraft's heading.

[0011] As described above, in the main landing gear of an electric vertical takeoff and landing aircraft, the lower end of a buffer 23 is connected to the middle of the main landing beam 22 by a first hinge bolt 31, and the upper end of the buffer 23 is connected to a buffer joint 231 by a second hinge bolt 32. The buffer 23 is rotatable about the axis of the second hinge bolt 32. The buffer joint 231 is fixedly connected to the fuselage 1 by bolts.

[0012] As described above, the main landing gear of an electric vertical takeoff and landing aircraft includes a buffer 23 that is an oil-gas buffer.

[0013] The present invention also provides an electric vertical takeoff and landing aircraft landing gear, comprising: a fuselage 1 installed at the bottom of the aircraft, a nose landing gear installed at the front end of the fuselage 1, and a pair of main landing gears 2 symmetrically installed on the left and right sides of the rear end of the fuselage, wherein the main landing gears 2 are the electric vertical takeoff and landing aircraft main landing gears described above.

[0014] As described above, the landing gear of an electric vertical takeoff and landing aircraft includes a fuselage 1 comprising a front frame 11, a rear frame 12, a side strip 13, and a longitudinal beam 14, which are bonded together to form a stable fuselage structure.

[0015] As described above, in an electric vertical takeoff and landing aircraft landing gear, the front frame 11 and the rear frame 12 are arranged in parallel. The left and right ends of the front frame 11 and the rear frame 12 are fixed together by side strips 13. The side strips 13 are located at the edges of the front frame 11 and the rear frame 12, and one end of the side strip 13 is connected to the front frame 11 and the other end is connected to the rear frame 12. The longitudinal beam 14 is divided into two longitudinal beams, left and right, which are symmetrically arranged in the middle of the front frame 11 and the rear frame 12. One end of the longitudinal beam 14 is connected to the front frame 11 and the other end is connected to the rear frame 12.

[0016] As described above, in an electric vertical takeoff and landing aircraft landing gear, the two ends of the main shaft 21 are hinged to the front frame 11 and the rear frame 12 via a front frame joint 16 and a rear frame joint 17, respectively, using fixed pins 15.

[0017] As described above, in an electric vertical takeoff and landing aircraft landing gear, the buffer joint 231 is fixedly connected to the side strip 13 of the fuselage 1 by bolts.

[0018] The beneficial effects achieved by this utility model are as follows:

[0019] (1) The main landing gear structure provided by this utility model can meet the requirements of load bearing and energy absorption when the aircraft lands;

[0020] (2) The main landing gear has a simple structural design, low structural process difficulty, short manufacturing cycle, low manufacturing cost, low assembly difficulty, easy maintenance, and a simple and clear load transfer path, resulting in a low structural weight.

[0021] (3) This utility model uses a buffer, which has a high efficiency in absorbing impact energy, good buffering performance, less overload on the body, and higher passenger comfort. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings.

[0023] Figure 1 This is a front view of the main structure of the landing gear of an electric vertical takeoff and landing aircraft provided in this embodiment of the utility model;

[0024] Figure 2 This is a top view of the main structure of the landing gear of an electric vertical takeoff and landing aircraft;

[0025] Figure 3 This is a side view of the main landing gear of an electric vertical takeoff and landing aircraft;

[0026] Figure 4 yes Figure 2 Cross-sectional view of position AA in the middle;

[0027] Figure 5 yes Figure 2 Cross-sectional view of the BB position.

[0028] Figure label:

[0029] 1. Airframe; 2. Main landing gear; 11. Front frame; 12. Rear frame; 13. Side strip; 14. Longitudinal beam; 15. Fixed pin; 16. Front frame joint; 17. Rear frame joint; 21. Main landing gear shaft; 22. Main landing gear beam; 23. Buffer; 231. Buffer joint; 24. Wheel; 241. Wheel axle; 25. Diagonal tie rod; 31. First hinge bolt; 32. Second hinge bolt; 33. Third hinge bolt; 34. Fourth hinge bolt. Detailed Implementation

[0030] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0031] Example

[0032] The electric vertical takeoff and landing (eVTOL) aircraft provided by this utility model has a tricycle landing gear, including a fuselage mounted at the bottom of the aircraft, a nose landing gear mounted at the front of the fuselage, and a pair of main landing gears symmetrically mounted on the left and right sides of the rear of the fuselage. The nose landing gear is the same as that of existing eVTOL aircraft and will not be described in detail here; the embodiments of this application mainly improve the main landing gear of the eVTOL aircraft.

[0033] See Figures 1-4 The figure shows the fuselage 1 of an electric vertical takeoff and landing aircraft and the main landing gear 2 on one side of the fuselage 1. The main landing gear on the other side (not shown in the figure) has the same structure as the landing gear on the first side and is symmetrically installed on the other side of the fuselage 1.

[0034] The top of the fuselage 1 is detachably mounted on the bottom of the aircraft. The fuselage 1 specifically includes a front frame 11, a rear frame 12, a side strip 13, and a longitudinal beam 14. The front frame 11, rear frame 12, side strip 13, and longitudinal beam 14 are composite material parts, which are bonded together to form an assembly.

[0035] The front frame 11 and rear frame 12 are arranged in parallel. The left and right ends of the front frame 11 and rear frame 12 are fixed together by side strips 13. The side strips 13 are located at the edges of the front frame 11 and rear frame 12, with one end connected to the front frame 11 and the other end connected to the rear frame 12. The longitudinal beams 14 are divided into left and right longitudinal beams, symmetrically arranged in the middle of the front frame 11 and rear frame 12. One end of the longitudinal beams 14 is connected to the front frame 11 and the other end is connected to the rear frame 12. The front frame 11, rear frame 12, side strips 13 and longitudinal beams 14 are glued together to form a stable body structure.

[0036] The main landing gear 2 includes a main landing shaft 21, a main landing beam 22, a buffer 23, and wheels 24. The two ends of the main landing shaft 21 are hinged to the front frame 11 and the rear frame 12 respectively via a front frame joint 16 and a rear frame joint 17 using fixed pins 15. The main landing shaft 21 can rotate around the axis of the fixed pins 15. The middle part of the main landing shaft 21 is fixedly welded to the front end of the main landing beam 22 in a perpendicular shape as an integral steel structure part. The end of the main landing beam 22 is equipped with and fixed to the wheels 24 via axle 241. The lower end of the buffer 23 is connected to the middle part of the main landing beam 22 via a first hinge bolt 31. The upper end of the buffer 23 is connected to the buffer joint 231 via a second hinge bolt 32. The buffer 23 can rotate around the axis of the second hinge bolt 32. The buffer joint 231 is a machined aluminum alloy part and is fixedly connected to the side strip 13 of the fuselage 1 by bolts.

[0037] The shock absorber 23 is preferably an oil-gas shock absorber. The advantages of an oil-gas shock absorber mainly include extending the service life of the main landing gear, reducing maintenance costs, improving efficiency, and enhancing performance. The oil-gas shock absorber mainly consists of a cylinder, piston, seals, and an oil-gas column. During operation, when the piston is subjected to an impact force and tilts into the cylinder, the gas inside the cylinder is compressed. Simultaneously, the piston inside the oil-gas column is pressurized and rises, compressing the oil-gas column at the top of the cylinder and generating a certain degree of elasticity. This reduces the impact force and decreases the amount of splashing and noise after the rebound.

[0038] The main landing gear 2 includes a main landing shaft 21, a main landing beam 22, a buffer 23, and wheels 24. When the aircraft lands, the landing gear can withstand the impact load. After the wheels 24 touch down, they move upwards, driving the main landing beam 22 and the main landing shaft 21 to rotate upwards around the axis of the main landing shaft 21 via the wheel axle 241. This compresses the buffer 23, causing it to shorten and withstand the upward load while absorbing the impact energy. Together with the wheels 24, the buffer 23 absorbs and dissipates the impact energy of the aircraft landing.

[0039] In addition, to ensure that the main landing gear 2 can withstand the directional load when the aircraft is traveling along the heading, the main landing gear 2 also includes a tie rod 25. The end of the main landing shaft 21 is connected to one end of the tie rod 25 through a third hinge bolt 33, and the other end of the tie rod 25 is connected to the main landing beam 22 through a fourth hinge bolt 34. The tie rod 25, the main landing shaft 21, and the main landing beam 22 together form a stable triangular structure to jointly bear the directional load of the aircraft.

[0040] Preferably, all components of the main landing gear 2 can be installed or disassembled individually, making installation and maintenance simple and easy, and the structure is easy to manufacture and assemble, making maintenance more convenient.

[0041] Working principle of this utility model:

[0042] Before the aircraft lands, the initial state of the main landing gear is as follows: Figure 1 As shown, the landing gear 24 sags due to gravity, and the lowest point of the landing gear 24 is lower than the lowest point of the fuselage 1, ensuring that the fuselage 1 will not touch the ground when the aircraft lands.

[0043] When the aircraft lands, the landing gear bears the impact load. After the wheels 24 touch the ground, the wheels 24 move upward, driving the main landing beam 22 and the main landing shaft 21 to rotate upward around the axis of the main landing shaft 21 via the wheel axle 241. This compresses the buffer 23, causing the buffer 23 to shorten and bear the upward load and absorb the impact energy. The limit compression stroke of the buffer 23 is limited, so that the wheels 24 remain below the lowest point of the fuselage 1 after landing, preventing the fuselage from hitting the ground. Moreover, the recovery process of the buffer 23 is slower than that of existing springs, resulting in less overload on the fuselage, better cushioning performance, higher energy absorption efficiency, and better comfort.

[0044] When the aircraft is in flight, the triangular structure formed by the tie rod 25, the main landing shaft 21, and the main landing beam 22 together bears the directional load, ensuring that the aircraft's course will not deviate due to structural deformation.

[0045] Throughout the process, the load transfer path is as follows: the main landing gear 2 transfers the load to the main landing shaft 21, the main landing beam 22 and the buffer 23 through the displacement change of the wheels 24. The main landing shaft 21 transfers the load to the front frame 11 and the rear frame 12 of the fuselage 1 through the joints at both ends of the main landing shaft 21 with the front frame 11 and the rear frame 12. The buffer 23 transfers the load to the side strip 13 through the buffer joint 231. Thus, the load transfer from the main landing gear 2 to the fuselage 1 is realized. The load transfer path is simple and clear.

[0046] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0047] In the description of this utility model, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. In addition, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0048] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

Claims

1. A main landing gear for an electric vertical takeoff and landing aircraft, characterized in that, include: The main lifting shaft (21), main lifting beam (22), buffer (23) and wheel (24) are connected to the machine body at both ends by fixed pins (15). The main lifting shaft (21) can rotate around the axis. The middle part of the main lifting shaft (21) is fixedly welded to the front end of the main lifting beam (22) in a perpendicular shape. The wheel (24) is installed at the end of the main lifting beam (22). The lower end of the buffer (23) is hinged to the middle part of the main lifting beam (22), and the upper end of the buffer (23) is hinged to the machine body.

2. The main landing gear of an electric vertical takeoff and landing aircraft as described in claim 1, characterized in that, The main landing gear also includes a tie rod (25), one end of which is hinged to the main landing shaft (21), and the other end is hinged to the main landing beam (22). The tie rod (25), the main landing shaft (21), and the main landing beam (22) together form a triangular structure.

3. The main landing gear of an electric vertical takeoff and landing aircraft as described in claim 1, characterized in that, The lower end of the buffer (23) is connected to the middle of the main beam (22) by the first hinge bolt (31), and the upper end of the buffer (23) is connected to the buffer joint (231) by the second hinge bolt (32). The buffer (23) can rotate around the axis of the second hinge bolt (32). The buffer joint (231) is fixedly connected to the machine body by bolts.

4. The main landing gear of an electric vertical takeoff and landing aircraft as described in claim 2, characterized in that, The buffer (23) is an oil-gas buffer.

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