Undercarriage limiting device and aircraft

Abstract

The invention belongs to the technical field of structural design, and particularly relates to an undercarriage limiting device and an aircraft, the limiting device comprises a double-lug upper joint, a double-lug lower joint, an upper mounting shaft, a lower mounting shaft and two limiting units; the double-lug upper joint is arranged on an outer barrel of the undercarriage buffer, and the double-lug lower joint is arranged on a piston rod of the undercarriage buffer; the upper mounting shaft and the lower mounting shaft are respectively mounted in the double-lug upper joint and the double-lug lower joint; the two limiting units are the same, and each limiting unit comprises a limiting rod and two limiting connectors; the two limiting connectors are arranged at the two ends of the limiting rod correspondingly and fixed to the upper mounting shaft and the lower mounting shaft correspondingly, and the stroke of the buffer piston rod relative to the buffer outer barrel is limited through the limiting rod.

Description

Technical Field

[0001] The invention belongs to the technical field of structural design, and in particular relates to a landing gear limiting device and an aircraft. Background Art

[0002] When a helicopter is moored, parked or towed on a platform on the sea, it will be in a shaking state due to the action of waves and sea breeze. The helicopter landing gear has the function of absorbing landing energy and reducing impact loads, and its functional design determines that it can perform telescopic movements. In order to keep the helicopter in a stable static state when it is moored and fixed on the ship's surface and prevent risks such as rollover and capsizing, it is necessary to limit the length of the helicopter landing gear to keep the overall posture of the helicopter stable. The current method for limiting the telescopic extension of the helicopter landing gear mainly uses a mechanical limit structure to longitudinally connect the upper and lower installation points of the landing gear to achieve a fixed telescopic limitation effect. However, it is limited by the installation position and installation space. Summary of the invention

[0003] The purpose of the present invention is to solve the problems of inconvenient installation, complicated operation and time-consuming installation of a helicopter landing gear limit device, reduce the difficulty of installation and improve product reliability. The present invention designs a landing gear limit device and an aircraft to meet the length locking requirements under different compression displacements of the landing gear, and can be quickly installed and easy to maintain.

[0004] The technical solution of the present invention:

[0005] A landing gear limiting device comprises: a double-ear upper joint, a double-ear lower joint, an upper mounting shaft, a lower mounting shaft and two limiting units;

[0006] The double-ear upper joint is arranged on the outer tube of the landing gear buffer, and the double-ear lower joint is arranged on the piston rod of the landing gear buffer;

[0007] The upper and lower mounting shafts are respectively mounted in the upper and lower double-ear joints;

[0008] The two limit units are identical, and each limit unit comprises a limit rod and two limit joints;

[0009] Two limit joints are respectively arranged at two ends of the limit rod, and the two limit joints are respectively fixed on the upper and lower mounting shafts, and the stroke of the buffer piston rod relative to the buffer outer cylinder is limited by the limit rod.

[0010] Further, the limiting rod includes an upper rod body and a lower rod body;

[0011] The upper rod body is an externally threaded rod, and the lower rod body is an internally threaded rod that matches it.

[0012] The upper rod body is screwed into the lower rod body, and the total length of the limit rod is adjusted by relative rotation of the upper and lower rod bodies.

[0013] Furthermore, the limiting rod comprises: an upper rod body, a lower rod body and an outer rotating cylinder;

[0014] The upper rod body and the lower rod body are both externally threaded rods with opposite thread rotation directions;

[0015] The outer rotating cylinder is provided with internal threads of equal length and opposite rotation directions;

[0016] The upper and lower rod bodies are respectively screwed in the outer rotating cylinder, and the total length of the limit rod is adjusted by rotating the outer rotating cylinder.

[0017] Further, the position-limiting joint comprises: a mounting socket and a semi-annular joint;

[0018] The installation nest is in the shape of a rectangular block, one end of which is fixed to the limiting rod, and the other end of which is provided with a semicircular groove;

[0019] The left and right sides of the installation nest are symmetrically provided with limiting bosses;

[0020] The inner wall of the semi-annular joint is symmetrically provided with guide grooves on both sides;

[0021] The limiting boss of the mounting socket is matched with the guide groove of the semi-circular joint to form a complete limiting joint, which is then sleeved on the upper and lower mounting shafts to achieve limiting in the length direction of the limiting rod.

[0022] Furthermore, the installation socket and the semi-circular joint are provided with locking wire holes and cooperate with a mooring wire to prevent the semi-circular joint from being lost.

[0023] Further, the limit joint includes: a joint block and a U-shaped joint;

[0024] One end of the joint block is fixed on the limit rod, and the other end is provided with a semicircular groove matching the upper and lower mounting shafts; pin holes are symmetrically provided on the left and right sides of the joint block;

[0025] A square groove is provided inside the U-shaped joint, and a semicircular groove matching the upper and lower mounting shafts is provided at the bottom of the square groove;

[0026] The side wall of the square groove of the U-shaped joint is provided with a lateral through hole;

[0027] A movable lever is hinged at the left and right ends of the outer side of the U-shaped joint, and a pin is arranged at the front end of the movable lever; the pin passes through the lateral through hole and is inserted into the pin hole to combine the joint block and the U-shaped joint into a complete limit joint.

[0028] Furthermore, the front end of the movable lever is a double ear, and waist-shaped holes are symmetrically provided on the two ear pieces; a movable shaft is provided in the waist-shaped hole, and one end of the pin shaft is connected to the movable shaft, and the position of the pin shaft is adjusted by moving the installation shaft in the waist-shaped hole.

[0029] Further, the limit joint includes a fixed head and a detachable head;

[0030] The fixing head is plate-shaped, one end of which is connected to the limiting rod, and the other end is provided with a through hole for connecting to the upper and lower mounting shafts;

[0031] The detachable head is a rectangular plate and one end in the length direction is arc-shaped. A concentric through hole is provided on one side of the arc-shaped detachable head for connecting with the upper and lower mounting shafts; the detachable head is symmetrically divided into two halves along a straight line passing through the center of the through hole and parallel to the length direction, one half is fixedly mounted on the limit rod, and the other half is provided with a mounting hole at one end away from the through hole, and is sleeved on the limit rod through the mounting hole, and the two halves of the detachable head are locked by a nut.

[0032] An aircraft comprises the landing gear limiting device.

[0033] Beneficial technical effects of the present invention:

[0034] 1. The upper rod 2 and the lower rod 3 of the limit device are screwed together with reverse threads to achieve the effect of lengthening and shortening the device. This operation method can reduce the time of adjusting the length of the device, is convenient and quick to use, and is easy to operate;

[0035] 2. A U-shaped hole is provided at the lower end of the movable lever 15. The design of the U-shaped hole 22 enables the entire limit device to have a small range of vertical length adjustment capability in the vertical direction. The limit device is adjusted so that the length of the limit device is just equal to the installation length, which is conducive to use in the case where the connection part is easy to loosen or there is an installation gap due to manufacturing errors of the parts structure, or the installation is difficult;

[0036] 3. The joints 5 and 19 of the limit device have good interchangeability and can be replaced separately when damaged, which is easy to replace;

[0037] 4. The main structure of the limit device is simple, the number of parts used is small, the entire device has a compact structure, light weight and high reliability.

[0038] 5. The main structure is subjected to vertical force, has a simple structure, and can withstand large vertical loads. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic diagram of a landing gear limit device;

[0040] Figure 2 is a schematic diagram of the limiting unit in the first embodiment;

[0041] Figure 3 is a schematic diagram of the limit joint in the first embodiment;

[0042] Figure 4 is a schematic diagram of the limiting joint in the second embodiment;

[0043] Figure 5 is a schematic diagram of the limiting unit in the third embodiment;

[0044] Figure 6 is a schematic diagram of the extension and contraction of the limiting unit in the third embodiment;

[0045] Numbering description: 1. Limiting unit; 2. Upper rod body; 3. Lower rod body; 4. Rod body end; 5. Joint; 6. Mounting socket; 7. Upper mounting shaft; 8. Lower mounting shaft; 9. Landing gear; 10. Double-ear upper joint; 11. Double-ear lower joint; 12. Mooring wire; 13. Guide groove; 14. Limiting boss; 15. Movable lever; 16. Anti-skid layer; 17. Support platform; 18. Rotating shaft; 19. Joint; 20. Mounting shaft; 21. Pin shaft; 21. Pin shaft; 22. U-shaped hole; 23. Nut; 24. Movable joint; 25. Movable joint; 26. Upper rod body; 27. Outer rotating rod; 28. Lower rod body; 29. ​​Mounting hole; 30. Nut boss. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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 creative work are within the scope of protection of the present invention.

[0047] Embodiment 1

[0048] A landing gear limit device is provided, which is composed of an upper rod body 2 with an external thread rod structure and a lower rod body 3 with an internal thread rod structure. The two rod bodies are coaxially screwed together through threads, and the upper rod body 2 is screwed into the internal cavity of the lower rod body 3, so as to achieve the extension and shortening of the device and adjust it within a certain length range. At the same time, the upper rod body 2, the lower rod body 3 and the joint 5 are assembled to form a set of limit rods, and the two sets of limit rods cooperate to form a split limit device 1. The joint 5 of the limit device has a guide groove 13, and the limit boss 14 on the rod body slides into the guide groove 13 to produce a vertical limit effect; in particular, the joint 5 has a locking wire hole and cooperates with the use of a mooring wire 12 for mooring, which can prevent the joint 5 from being lost after being removed.

[0049] Embodiment 2

[0050] like Figure 4The joint 19 has a movable lever 15, which extends out of the support platform 17, and the rotating shaft 18 is inserted into the hole on the support platform 17 to form an assembly relationship; the lower end of the movable lever 15 has a mounting shaft 20, which is inserted into the end mounting hole of the pin 21 and the U-shaped hole 22, forming an installation relationship of the pin 21 on the movable lever 15; when the movable lever 15 rotates around the rotating shaft 18, the pin 21 can enter or be pulled out of the cylindrical hole of the rod end 4, and when the pin 21 enters the cylindrical hole of the rod end 4, the vertical installation function of the limit device can be achieved. In particular, the joint 19 has the feature of the anti-slip layer area 16, which is conducive to the finger pressing without slipping; the design of the U-shaped hole 22 allows the entire limit device to have a small range of vertical length adjustment capability in the vertical direction.

[0051] Limiting method:

[0052] (a) The landing gear 9 is provided with a double-ear upper joint 10, a double-ear lower joint 11, an upper mounting shaft 7, and a lower mounting shaft 8; the upper mounting shaft 7 is inserted into the double-ear upper joint 10 to form an assembly relationship, and the lower mounting shaft 8 is inserted into the double-ear lower joint 11 to form an assembly relationship, and the outer contour ends of the upper mounting shaft 7 and the lower mounting shaft 8 protruding from the double-ear upper joint 10 and the double-ear lower joint 11 constitute the installation position of the limit device;

[0053] (b) pre-adjust the length of the limiting device according to the real-time position distance between the upper mounting shaft 7 and the lower mounting shaft 8 of the landing gear, and make the joint 5 (or joint 19) close to the upper mounting shaft 7 and the lower mounting shaft 8;

[0054] (c) Remove the stopper joint 5 (or joint 19); in particular, for the first joint design configuration (such as Figure 3 ), the joint needs to be slid out from the rod body boss; for the second joint design configuration, the joint can be taken out upward as a whole by pressing the two movable levers to rotate them inward around the rotation axis (such as Figure 4 );

[0055] (d) Adjust the rod length of the limiting device so that the mounting socket 6 of the rod end 4 of the lower rod 3 fits with the lower mounting shaft 8, and then install and fix the mounting joint 5 (or joint 19) located below the limiting device;

[0056] (e) Continue to adjust the rod length of the limit device so that the mounting socket 6 of the rod end 4 of the upper rod 2 fits with the upper mounting shaft 7. At this time, install and fix the mounting joint 5 (or joint 19) located above the limit device so that the limit device is fixed on the landing gear as a whole.

[0057] Embodiment 3

[0058] The limiting device is composed of an upper rod body 26, an outer rotating rod 27, and a lower rod body 28, which are screwed together to form a main structure. The movable joints 24 and 25 are inserted into the axial ends of the upper rod body 26 and form an installation relationship with the upper mounting shaft 7. After the installation is completed, the nut 23 locks the limiting device to limit its axial direction. In particular, the lower end of the lower rod body 28 has a mounting hole 29, and the size of the mounting hole 29 is larger than the maximum diameter of the lower mounting shaft 8.

[0059] The corresponding limiting methods are as follows:

[0060] (a) According to the real-time position distance between the upper mounting shaft 7 and the lower mounting shaft 8 of the landing gear, the length of the limiting device is pre-adjusted so that the overall rod length of the limiting device is close to the vertical distance of the mounting shaft;

[0061] (b) fitting the mounting hole 29 at the lower end of the lower rod body 28 onto the lower mounting shaft;

[0062] (c) Remove the nut 23 and remove the movable joint 24 of the limit device;

[0063] (c) Continue to adjust the rod length of the limit device until the semicircular shaft hole of the limit device movable joint 25 just fits against the lower semicircle of the shaft surface of the mounting shaft 7 on the landing gear;

[0064] (d) Lock the limit device using the nut 24;

[0065] 1. The joint 5 has a guide groove 13, and the limiting boss 14 on the rod body slides into the guide groove 13 to produce a vertical limiting effect;

[0066] 2. The lower end of the movable lever 15 is provided with a U-shaped hole. The design of the U-shaped hole 22 enables the entire limit device to have a small range of vertical length adjustment capability. The limit device is adjusted so that the length of the limit device is exactly equal to the installation length, which is conducive to use when the connection part is easy to loosen or there is an installation gap due to manufacturing errors of the parts structure, or when the installation is difficult.

[0067] 3. The joint 19 has the feature of the anti-slip layer area 16, which is conducive to the finger pressing without slipping;

[0068] 4. The first design mode: the connector 5 has a locking wire hole and is used with the use of the tethering wire 12 for tethering, and the connector 5 can be tethered after being disassembled;

[0069] 5. The upper rod 26, the outer rotating rod 27, and the lower rod 28 are screwed together to form the main structure. The upper rod 26 and the lower rod 28 are screwed together through the outer rotating rod 27 with reverse threads to enter the cavity of the outer rotating rod 27 to achieve the effect of lengthening and shortening the device. This operation method can reduce the time for adjusting the length of the device, is convenient and quick to use, and is easy to operate;

[0070] 6. The limit device 1 is composed of two sets of limit rod structures, forming a split limit installation method, which is conducive to load dispersion and lightweight design for easy installation;

[0071] 7. The outer rotating rod 27 has a nut boss 30. When the length of the limit device is adjusted, if the outer rotating rod 27 is stuck in rotation relative to the lower rod body 28, the nut boss 30 can be tightened with the help of an external tool (such as an open-end wrench), thereby screwing the outer rotating screw rod 27 as a whole;

[0072] 8. The diameter of the outermost shaft end of the upper mounting shaft 7 is larger than the diameter of the mounting section, and the diameter of the mounting holes of the movable joints 24 and 25 matches the diameter of the mounting section, so that after installation, the outermost shaft end of the upper mounting shaft 7 has a lateral limiting effect on the limiting device, and the limiting device cannot fall out laterally.

[0073] The above is only a specific embodiment of the present invention, and the present invention is described in detail. The unexplained part is a conventional technology. However, the protection scope of the present invention is not limited to this. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. The protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A landing gear limit device, Features: The device comprises: a double-ear upper joint, a double-ear lower joint, an upper mounting shaft, a lower mounting shaft and two limit units; The double-ear upper joint is arranged on the outer tube of the landing gear buffer, and the double-ear lower joint is arranged on the piston rod of the landing gear buffer; The upper and lower mounting shafts are respectively mounted in the upper and lower double-ear joints; The two limit units are identical, and each limit unit comprises a limit rod and two limit joints; Two limit joints are respectively arranged at two ends of the limit rod, and the two limit joints are respectively fixed on the upper and lower mounting shafts, and the stroke of the buffer piston rod relative to the buffer outer cylinder is limited by the limit rod.

2. The device according to claim 1, Features: The limiting rod comprises an upper rod body and a lower rod body; The upper rod body is an externally threaded rod, and the lower rod body is an internally threaded rod that matches it. The upper rod body is screwed into the lower rod body, and the total length of the limit rod is adjusted by relative rotation of the upper and lower rod bodies.

3. The device according to claim 2, Features: The limiting rod comprises: an upper rod body, a lower rod body and an outer rotating cylinder; The upper rod body and the lower rod body are both externally threaded rods with opposite thread rotation directions; The outer rotating cylinder is provided with internal threads of equal length and opposite rotation directions; The upper and lower rod bodies are respectively screwed in the outer rotating cylinder, and the total length of the limit rod is adjusted by rotating the outer rotating cylinder.

4. The device according to claim 3, Features: The limit joint comprises: a mounting socket and a semi-annular joint; The installation nest is in the shape of a rectangular block, one end of which is fixed to the limiting rod, and the other end of which is provided with a semicircular groove; The left and right sides of the installation nest are symmetrically provided with limiting bosses; The inner wall of the semi-annular joint is symmetrically provided with guide grooves on both sides; The limiting boss of the mounting socket is matched with the guide groove of the semi-circular joint to form a complete limiting joint, which is then sleeved on the upper and lower mounting shafts to achieve limiting in the length direction of the limiting rod.

5. The device according to claim 4, Features: The installation nest and the semi-circular joint are provided with locking wire holes and cooperate with the mooring wire to prevent the semi-circular joint from being lost.

6. The device according to claim 4, Features: The limit joint includes: a joint block and a U-shaped joint; One end of the joint block is fixed on the limit rod, and the other end is provided with a semicircular groove matching the upper and lower mounting shafts; pin holes are symmetrically provided on the left and right sides of the joint block; A square groove is provided inside the U-shaped joint, and a semicircular groove matching the upper and lower mounting shafts is provided at the bottom of the square groove; The side wall of the square groove of the U-shaped joint is provided with a lateral through hole; A movable lever is hinged at the left and right ends of the outer side of the U-shaped joint, and a pin is arranged at the front end of the movable lever; the pin passes through the lateral through hole and is inserted into the pin hole to combine the joint block and the U-shaped joint into a complete limit joint.

7. The device according to claim 6, Features: The front end of the movable lever is double ears, and waist-shaped holes are symmetrically arranged on the two ears; a movable shaft is arranged in the waist-shaped hole, and one end of the pin shaft is connected to the movable shaft, and the position of the pin shaft is adjusted by moving the installation shaft in the waist-shaped hole.

8. The device according to claim 4, Features: The limit joint includes a fixed head and a detachable head; The fixing head is plate-shaped, one end of which is connected to the limiting rod, and the other end is provided with a through hole for connecting to the upper and lower mounting shafts; The detachable head is a rectangular plate and one end in the length direction is arc-shaped. A concentric through hole is provided on one side of the arc-shaped detachable head for connecting with the upper and lower mounting shafts; the detachable head is symmetrically divided into two halves along a straight line passing through the center of the through hole and parallel to the length direction, one half is fixedly mounted on the limit rod, and the other half is provided with a mounting hole at one end away from the through hole, and is sleeved on the limit rod through the mounting hole, and the two halves of the detachable head are locked by a nut.

9. An aircraft, Features: The aircraft comprises the landing gear limiting device according to any one of claims 1-8.

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