Electric vertical take-off and landing aircraft landing gear

Abstract

The utility model discloses an electric vertical take-off and landing aircraft landing gear, and relates to the technical field of aircrafts. The electric vertical take-off and landing aircraft landing gear comprises an aircraft body installed at the bottom of an aircraft, a front landing gear installed at the front end of the aircraft body and a pair of main landing gears symmetrically installed on the left side and the right side of the rear end of the aircraft body. 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] The utility model relates to the field of aircrafts, in particular to a landing gear of an electric vertical takeoff and landing aircraft. Background Art

[0002] In recent years, Evtol (electric vertical takeoff and landing aircraft) has become the most important urban air traffic solution due to its important advantages of environmental protection and low dependence on infrastructure. Among them, the landing gear, as a main component of the aircraft, during the takeoff and landing of the aircraft, through the combined action of the tires and shock absorption devices, reduces the impact force between the aircraft and the ground to a level that the structure can withstand, ensuring the safe takeoff and landing of the aircraft.

[0003] Currently, the main landing gears of 1-2 ton general aircraft generally use steel leaf springs in combination with tires to achieve the functions of shock resistance and shock absorption. Its structure is relatively simple, can withstand heavy loads, and absorbs shock energy through the elastic deformation of the leaf spring, which can meet the needs of the safe flight and operation of the aircraft. However, the main landing gear of general aircraft has the following deficiencies:

[0004] ① The elastic deformation of the leaf spring and the efficiency of absorbing shock energy are relatively low;

[0005] ② To meet sufficient energy absorption, the leaf spring requires a large deformation amount, and thus requires a sufficient length of the leaf spring, resulting in a relatively large structural weight;

[0006] ③ The heat treatment requirements and processing technology requirements for the steel raw materials of the leaf spring are relatively high, otherwise it is easy to fail to meet the design indicators;

[0007] ④ After the elastic deformation of the leaf spring, the elastic recovery process is very fast, resulting in a relatively large overload on the airframe and poor comfort for passengers.

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

[0009] The 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. Both ends of the main landing shaft 21 are hinged to the airframe 1 through fixed pin shafts 15. The main landing shaft 21 can rotate around its axis. The middle part of the main landing shaft 21 is fixedly welded perpendicularly to the front end of the main landing beam 22. The wheel 24 is installed at the end of the main landing beam 22; the lower end of the buffer 23 is hinged in the middle of the main landing beam 22, and the upper end of the buffer 23 is hinged to the airframe 1.

[0010] A main landing gear of an electric vertical takeoff and landing aircraft as described above, wherein the main landing gear 2 further includes an inclined tie rod 25. One end of the inclined tie rod (25) is hinged to the main landing shaft (21), and the other end is hinged to the main landing beam (22). The inclined tie rod 25, the main landing shaft 21, and the main landing beam 22 together form a stable triangular structure to jointly bear the load in the aircraft's heading direction.

[0011] A main landing gear of an electric vertical takeoff and landing aircraft as described above, wherein the lower end of a buffer 23 is connected to the middle part of the main landing beam 22 through a first hinge bolt 31, and the upper end of the buffer 23 is connected to a buffer joint 231 through a 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 airframe 1 through bolts.

[0012] A main landing gear of an electric vertical takeoff and landing aircraft as described above, wherein the buffer 23 is an oil-gas buffer.

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

[0014] A landing gear of an electric vertical takeoff and landing aircraft as described above, wherein the airframe 1 includes a front frame 11, a rear frame 12, side strips 13, and longitudinal beams 14. The front frame 11, the rear frame 12, the side strips 13, and the longitudinal beams 14 are bonded to form a stable airframe structure.

[0015] A landing gear of an electric vertical takeoff and landing aircraft as described above, wherein 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 respectively fixed together through 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 beams 14 are divided into left and right longitudinal beams and 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] A landing gear of an electric vertical takeoff and landing aircraft as described above, wherein both ends of the main landing shaft 21 are respectively hinged to the front frame 11 and the rear frame 12 through fixing pin shafts 15 via a front frame joint 16 and a rear frame joint 17.

[0017] A landing gear of an electric vertical takeoff and landing aircraft as described above, wherein the buffer joint 231 is fixedly connected to the side strip 13 of the airframe 1 through bolts.

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

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

[0020] (2) The design configuration of the main landing gear structure is simple, with 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 relatively low structural weight;

[0021] (3) The present utility model uses a buffer, which has a high efficiency in absorbing impact energy, good buffering performance, a small overload on the airframe, and high passenger comfort. Description of the Drawings

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the present utility model. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings.

[0023] Figure 1 It is the front view of the main structure of the landing gear of the electric vertical takeoff and landing aircraft provided by the embodiment of the present utility model;

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

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

[0026] Figure 4 It is Figure 2 The sectional view at the A - A position in

[0027] Figure 5 It is Figure 2 The sectional view at the B - B position in

[0028] Reference Signs:

[0029] 1. Airframe; 2. Main landing gear; 11. Front frame; 12. Rear frame; 13. Side strip; 14. Longitudinal beam; 15. Fixed pin shaft; 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 shaft; 25. Diagonal tie rod; 31. First hinge bolt; 32. Second hinge bolt; 33. Third hinge bolt; 34. Fourth hinge bolt. Detailed Embodiment

[0030] Combined with the accompanying drawings in the embodiments of the present utility model, the technical solutions in the embodiments of the present utility model are clearly and completely described. Obviously, the described embodiments are part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative work belong to the protection scope of the present utility model.

[0031] Embodiment

[0032] The electric vertical takeoff and landing aircraft provided by the present utility model has a three-point landing gear, including a fuselage installed at the bottom of the aircraft, a nose landing gear installed at the front end of the fuselage, and a pair of main landing gears symmetrically installed on the left and right sides at the rear end of the fuselage. Among them, the nose landing gear is the same as that of the existing electric vertical takeoff and landing aircraft and will not be described in detail here; the embodiments of the present application mainly improve the main landing gear of the electric vertical takeoff and landing aircraft.

[0033] Refer to Figures 1 to 4 , the figure shows the fuselage 1 of the 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 this side and is symmetrically installed on the other side of the fuselage 1.

[0034] The top of the fuselage 1 is detachably installed at the bottom of the aircraft. The fuselage 1 specifically includes a front frame 11, a rear frame 12, side strips 13, and longitudinal beams 14. The front frame 11, rear frame 12, side strips 13, and longitudinal beams 14 are composite material parts and are formed into a component by bonding.

[0035] 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 respectively fixed together by the 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 beams 14 are divided into two left and right longitudinal beams and 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. Through the bonding of the front frame 11, rear frame 12, side strips 13, and longitudinal beams 14, a stable fuselage structure is formed.

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

[0037] The buffer 23 is preferably an oil-gas buffer. The advantages of the oil-gas buffer mainly include extending the service life of the main landing gear, reducing maintenance costs, better efficiency and better performance. The oil-gas buffer is mainly composed of a cylinder body, a piston, a seal, an oil-gas column, etc. During the operation of the buffer, when the piston is impacted and thus tilts and moves into the cylinder body, the gas in the cylinder body will be compressed. At the same time, the piston in the oil-gas column will be pressured and rise, causing the oil-gas column at the top of the cylinder body to be compressed, generating a certain elasticity, thereby reducing the impact force and reducing the spatter amount and noise after the rebound.

[0038] In the main landing gear 2, the main landing gear shaft 21, the main landing gear beam 22, the buffer 23 and the wheel 24 are arranged such that when the aircraft lands, the landing gear bears the impact load. After the wheel 24 touches the ground, the wheel moves upward, driving the main landing gear beam 22 and the main landing gear shaft 21 to rotate upward around the axis of the main landing gear shaft 21, compressing the buffer 23. The buffer 23 shortens to bear the upward load and absorb the impact energy. The buffer 23 and the wheel 24 together absorb and dissipate the impact energy of the aircraft landing.

[0039] In addition, to ensure that the aircraft can bear the load in the aircraft's heading direction when moving forward along the heading, the main landing gear 2 further includes a diagonal tie rod 25. One end of the diagonal tie rod 25 is connected to the end of the main landing gear shaft 21 through a third hinge bolt 33, and the other end of the diagonal tie rod 25 is connected to the main landing gear beam 22 through a fourth hinge bolt 34. The diagonal tie rod 25, the main landing gear shaft 21 and the main landing gear beam 22 together form a stable triangular structure to jointly bear the load in the aircraft's heading direction.

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

[0041] The working principle of the present utility model:

[0042] Before the aircraft lands, the initial state of the main landing gear is asFigure 1 As shown, the landing gear 24 droops due to gravity, and the lowest point of the landing gear 24 is lower than the lowest point of the airframe 1, ensuring that the airframe 1 will not touch the ground when the aircraft lands.

[0043] When the aircraft lands, the landing gear bears impact loads. After the landing gear 24 touches the ground, the landing gear 24 moves 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 through the axle 241, compressing the buffer 23. The buffer 23 shortens to bear the upward load and absorb the impact energy. The limit compression stroke of the buffer 23 is limited, so that the landing gear 24 is still lower than the lowest point of the airframe 1 after touching the ground, preventing the airframe from hitting the ground. Moreover, the recovery process of the buffer 23 is slower than that of the existing spring, resulting in a smaller overload on the airframe, better buffering performance, higher energy absorption efficiency, and better comfort.

[0044] When the aircraft is in flight, the diagonal tie rod 25 and the triangular structure composed of the main landing shaft 21 and the main landing beam 22 together bear the course load, ensuring that the course of the aircraft will not yaw due to structural deformation.

[0045] During the whole 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 landing gear 24. The main landing shaft 21 transfers the load to the front frame 11 and the rear frame 12 of the airframe 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, thereby realizing the load transfer from the main landing gear 2 to the airframe 1. The load transfer path is simple and clear.

[0046] For those skilled in the art, it is obvious that the present utility model is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present utility model. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present utility model is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present utility model. Any reference signs in the claims should not be regarded as limiting the claims involved.

[0047] In the description of the present utility model, unless otherwise specified, "a plurality of" means two or more; the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present utility model. In addition, terms such as "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0048] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "connected" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

Claims

1. An electric vertical take-off and landing aircraft landing gear, characterized in that: include: A fuselage (1) mounted at the bottom of the aircraft, a front landing gear mounted at the front end of the fuselage (1), and a pair of main landing gears (2) mounted symmetrically on the left and right sides of the rear end of the fuselage; The main landing gear (2) comprises a main lifting shaft (21), a main lifting beam (22), a buffer (23) and a wheel (24); both ends of the main lifting shaft (21) are hinged to the body via a fixed pin shaft (15); the main lifting shaft (21) can rotate around an axis; the middle of the main lifting shaft (21) is fixedly welded to the front end of the main lifting beam (22) in a vertical form; 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 of the main lifting beam (22); and the upper end of the buffer (23) is hingedly connected to the body.

2. The electric vertical take-off and landing aircraft landing gear according to claim 1, characterized in that: The machine body (1) comprises a front frame (11), a rear frame (12), side strips (13) and longitudinal beams (14); the front frame (11), the rear frame (12), the side strips (13) and the longitudinal beams (14) are bonded together to form a stable machine body structure.

3. The electric vertical take-off and landing aircraft landing gear according to claim 2, characterized in that: The front frame (11) and the rear frame (12) are arranged in parallel, and the left and right ends of the front frame (11) and the rear frame (12) are respectively 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 left and right longitudinal beams, and is symmetrically arranged in the middle of the front frame (11) and the rear frame (12), and 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).

4. The electric vertical take-off and landing aircraft landing gear according to claim 3, characterized in that: Both ends of the main starting shaft (21) are hingedly connected to the front frame (11) and the rear frame (12) through a front frame joint (16) and a rear frame joint (17) respectively using fixed pin shafts (15).

5. The electric vertical take-off and landing aircraft landing gear according to claim 3, characterized in that: The buffer joint (231) is fixedly connected to the side bar (13) of the machine body (1) by means of bolts.

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