Automatic jacking and locking device for nose landing gear of an aircraft

Abstract

This invention belongs to the field of aircraft ground simulation verification test technology, and specifically relates to an automatic nose landing gear lifting and locking device for an aircraft. It includes: a landing gear synchronous lifting mechanism, a rotating mechanism, and a locking mechanism; the landing gear synchronous lifting mechanism is disposed on the ground and is used to raise or lower the landing gear; the rotating mechanism is disposed on the landing gear synchronous lifting mechanism and is used to drive the landing gear to rotate; the locking mechanism is disposed between the rotating mechanism and the landing gear synchronous lifting mechanism and is used to lock the rotating mechanism to prevent it from rotating arbitrarily.

Description

Technical Field

[0001] This invention belongs to the field of aircraft ground simulation verification test technology, and discloses an automatic lifting and locking device for aircraft nose landing gear. Background Technology

[0002] The functional and performance testing of the aircraft's nose landing gear steering system is a crucial test that must be completed before the aircraft's maiden flight. This requires a 1:1 scale model of the nose landing gear to be installed on a test rig. Generally, when designing a ground test rig, to ensure smooth installation of the nose landing gear and to enable normal nose landing gear retraction and extension testing, a certain distance must be maintained between the bottom of the nose landing gear wheels and the ground when the nose landing gear is in its fully extended position. This distance prevents the nose landing gear from simulating the compression of the nose landing gear strut structure during landing to obtain a grounding signal, thus hindering the steering system control operation. Therefore, to conduct nose landing gear steering function and performance testing on the test rig, a nose landing gear lifting device must be designed to obtain the nose landing gear grounding signal, simulating ground conditions, and completing the nose landing gear steering function and performance test.

[0003] Currently, domestically produced nose landing gear lifting devices mainly employ hydraulic drive, with the lifting actuator and guide column fixedly installed via a top plate assembly. Its function is relatively simple, with low automation; it can only control the up and down lifting motion of the nose landing gear and allow it to move freely with the turning system. This type of nose landing gear lifting device has the following disadvantages:

[0004] 1) When the aircraft's nose landing gear is turning, a large turning torque is generated along the nose landing gear buffer strut. The existing lifting device is generally a single lifting actuating cylinder, which has a weak load-bearing capacity. Furthermore, due to an unsuitable lifting position, the entire device may experience a certain eccentric force during rotation.

[0005] 2) Existing test requirements have been changed. The aircraft designers have added verification of the impact of ground friction on the functional performance of the turning system during turns. The original jacking device can only achieve free movement of the nose landing gear during turns, and cannot truly simulate the ground friction when the nose landing gear wheels turn. Summary of the Invention

[0006] The purpose of this invention is to provide an automatic nose landing gear lifting and locking device for aircraft, which addresses the shortcomings of existing technologies. Through the structural design of a dual lifting actuating cylinder and precise lifting control, stability and load-bearing capacity are improved. By using a rotating mechanism and locking device, the influence factors of ground friction during nose landing gear turning are realistically simulated, thereby meeting the functional performance verification requirements of the nose landing gear turning system during aircraft ground simulation tests.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0008] An automatic nose landing gear lifting and locking device for an aircraft includes: a landing gear synchronous lifting mechanism, a rotating mechanism, and a locking mechanism;

[0009] The landing gear synchronous lifting mechanism is installed on the ground and is used to raise or lower the landing gear.

[0010] The rotating mechanism is mounted on the landing gear synchronous lifting mechanism and is used to drive the landing gear to rotate;

[0011] The locking mechanism is located between the rotating mechanism and the landing gear synchronous lifting mechanism to lock the rotating mechanism and prevent it from rotating arbitrarily.

[0012] Furthermore, the landing gear synchronous lifting mechanism includes: a base, a lifting cylinder, a connecting beam, a support plate, and a bracket;

[0013] The two bases are fixed to the ground, and the connecting beam connects the two bases;

[0014] Two lifting cylinders are fixed on two bases respectively; the actuating rods of the lifting cylinders are connected to the brackets;

[0015] The support plate is fixedly connected to the two brackets;

[0016] The actuators of the two lifting cylinders indirectly drive the support plate to move up and down through the bracket.

[0017] Furthermore, the landing gear synchronous lifting mechanism also includes: a guiding mechanism;

[0018] The end of the connecting beam is provided with a guide mechanism perpendicular to the ground;

[0019] The bracket has a guide hole, and the bracket is sleeved on the guide mechanism through the guide hole;

[0020] The guide mechanism guides the up-and-down movement of the support.

[0021] Furthermore, a safety stop is provided at the top of the guide mechanism; the safety stop is used to limit the movement stroke of the support. This physical limitation prevents the lifting mechanism from over-lifting beyond its stroke, thus avoiding potential danger.

[0022] Furthermore, a switch detection plate is provided at the top of the guide mechanism;

[0023] The switch detection board is used to depressurize the lifting cylinder after detecting that the bracket has moved to its maximum stroke, thus preventing it from exceeding its stroke limit. At the control level, when the lifting mechanism is detected to have moved to its maximum stroke, the lifting cylinder is depressurized, causing it to stop moving.

[0024] Furthermore, the rotating mechanism includes: a lifting disc, a surface bearing, and an inner shaft of a collar;

[0025] The center of the lifting plate is provided with a circular embedded hole;

[0026] The inner shaft of the collar is a two-step shaft, and the top of the inner shaft of the collar is embedded in the circular inner hole of the lifting plate. The inner ring of the collar is fixed to the lifting plate by countersunk bolts.

[0027] A planar bearing is embedded in the center of the support plate, and the bottom of the inner shaft of the collar mates with the planar bearing.

[0028] Furthermore, the diameter of the lifting plate is not less than twice the front wheel track, and the thickness is not less than 20 mm.

[0029] Furthermore, the locking mechanism includes: a torque sensor connecting shaft, a mounting plate, a clamping cylinder, a limit pin, and a locking disc;

[0030] An mounting plate is installed at the bottom of the support plate, and the clamping cylinder is fixed to the mounting plate;

[0031] A limit pin is connected to the actuating rod of the clamping cylinder, and the limit pin slides in the guide groove of the mounting plate by the actuation of the clamping cylinder;

[0032] A torque sensor is installed below the center of the lifting plate. The lower end of the torque sensor is connected to the torque sensor connecting shaft, and the lower end of the torque sensor connecting shaft is inserted into the center hole of the locking plate.

[0033] The locking disc is provided with a pin slot;

[0034] The limit pin is inserted into or pulled out of the pin slot by the clamping cylinder to achieve circumferential locking and unlocking of the lifting plate.

[0035] Furthermore, the locking mechanism also includes a reset mechanism;

[0036] The reset mechanism includes: a connecting disc, a drive disc, a synchronous belt, a driving pulley, a driven pulley, a pulley connecting shaft, a motor mounting plate, and a drive motor;

[0037] After the torque sensor connecting shaft is inserted into the locking disc, the locking disc, connecting disc, drive disc, and drive wheel are mounted on the motor mounting plate through the locking nut and pulley connecting shaft;

[0038] A motor mounting plate is fixed at the top center of the connecting beam, and the drive motor is installed at the bottom of the motor mounting plate;

[0039] The output shaft of the drive motor is fixedly connected to the driven wheel, and the driven wheel is connected to the driving wheel through a synchronous belt and drives the driving wheel to rotate;

[0040] The drive wheel drives the drive disc and connecting disc to rotate, which in turn drives the locking disc to rotate and reset.

[0041] The beneficial effects of this application are as follows:

[0042] 1) It has two working modes: free rotation around the axis and fixed. It can be quickly and conveniently switched according to the needs of the nose landing gear turning test. The fixed working mode can simultaneously realize the free turning of the wheels and simulate the real ground friction of the aircraft, meeting the ground test requirements of the new turning system.

[0043] 2) Upon receiving control commands, one-button operation can effectively and orderly control the operation and shutdown of components. It collects relevant parameter data and precisely adjusts the device's motion state through real-time closed-loop feedback control. It can raise and retract the front landing gear at any position and features multiple functions such as automatic one-button raising and limit safety stopping. It boasts a high degree of automation and ease of use.

[0044] 3) The automatic aircraft lifting and locking device of this application has low development cost, flexible operation, and high popularization value in the new field of aviation ground testing. Attached Figure Description

[0045] To more clearly illustrate the technical solutions and advantages in the embodiments of this application or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0046] Figure 1 This is a schematic diagram of the overall structure of the automatic lift-up and locking device for the aircraft's nose landing gear.

[0047] Figure 2 This is a schematic diagram of the synchronous lifting mechanism.

[0048] Figure 3 This is a schematic diagram of a rotating mechanism.

[0049] Figure 4 This is a schematic diagram of the locking device.

[0050] Among them, 1—base, 2—lifting cylinder, 3—connecting beam, 4—support plate, 5—bracket, 6—guide mechanism, 7—safety stop, 8—switch detection plate, 9—plane bearing, 10—inner shaft of collar, 11—lifting plate, 12—pin mounting plate, 13—torque sensor connecting shaft, 14—clamping cylinder, 15—limit pin, 16—locking plate, 17—connecting plate, 18—detection switch bracket, 19—support, 20—locking nut, 21—drive plate, 22—synchronous belt, 23—drive pulley, 24—driven pulley, 25—pulley connecting shaft, 26—connecting bolt, 27—motor mounting plate, 28—drive motor. Detailed Implementation

[0051] The present application will be further described in detail below with reference to the accompanying drawings of the embodiments.

[0052] An automatic nose landing gear lifting and locking device for aircraft mainly includes a landing gear synchronous lifting mechanism, a rotating mechanism, and a locking device.

[0053] The synchronous lifting mechanism includes a base, lifting cylinders, connecting beams, support plates, brackets, and guide mechanisms. It adopts a symmetrical distribution of double lifting cylinders on both sides. The top of the lifting cylinders is connected to the brackets. The lifting and lowering of the brackets is achieved by extending and retracting the cylinders. To improve the lifting stability, a guide mechanism is designed on the connecting beam. To provide structural support for the rotating mechanism, a support plate is designed and fixedly connected to the lifting brackets at both ends to form a whole.

[0054] The rotating mechanism includes a plane bearing, an inner shaft of a collar, and a lifting plate. A plane bearing is embedded in the center of the synchronous lifting mechanism support plate. The plane bearing is then precisely fitted with the inner shaft of the collar and embedded in the inner hole of the lifting plate bearing, so that the lifting plate has the function of rotating around the central axis and providing contact support for the machine wheel.

[0055] The locking device comprises a pin mounting plate, a torque sensor connecting shaft, a clamping cylinder, a limit pin, a locking disc, a connecting disc, a drive disc, a synchronous belt, a drive wheel, a driven wheel, a pulley connecting shaft, and a drive motor. The clamping cylinder and the pin mounting plate are connected as a whole and installed at the bottom of the synchronous lifting mechanism support plate. The torque sensor and the connecting shaft are connected to the bottom of the lifting plate of the rotating mechanism with a tight fit. The lower part of the connecting shaft is inserted into the center of the locking disc, and then the connecting disc, drive disc, drive wheel, and pulley connecting shaft are installed onto the motor mounting plate by locking nuts. The drive wheel and the driven wheel are connected by a synchronous belt. The motor mounting plate is installed at the top middle position of the synchronous lifting mechanism connecting beam. The drive motor is installed at the bottom of the motor mounting plate. The motor drives the driven wheel, and the driven wheel drives the drive wheel through the synchronous belt, thereby driving the drive disc to move.

[0056] A pin slot is designed on the locking plate to allow the limit pin to engage in the locked state, thus achieving a fixed clamping of the lifting plate. A limit pin is installed at the end of the clamping cylinder rod, and the extension and retraction of the limit pin are controlled by the extension and retraction of the cylinder. That is, when extended, the lifting plate of the rotating mechanism is in a locked state, and when retracted, the lifting plate of the rotating mechanism is in a free state. At the same time, a guide groove is designed on the pin mounting plate to enhance the structural strength of the clamping device.

[0057] When the rotating mechanism needs to be reset, the origin can be reset by driving the locking disc in the drive disc through the driven wheel and the driving wheel via the drive motor.

[0058] This invention has been applied in the verification test of the turning system of the landing gear wheels on the iron bird test stand of a certain type of large amphibious aircraft, and the ground verification test of the aircraft turning system has been completed.

[0059] Referring to the attached figures, the main structure of an automatic nose landing gear lifting and locking device for an aircraft includes a landing gear synchronous lifting mechanism, a rotation mechanism, and a locking mechanism.

[0060] The synchronous lifting mechanism consists of a base 1, lifting cylinders 2, connecting beams 3, support plates 4, brackets 5, guide mechanisms 6, safety stops 7, and switch detection plates 8. The base 1 is connected to the ground to prevent the device from shifting during turning. The lifting cylinders 2 are symmetrically distributed on both sides of the base 1, and the bases 1 are connected by connecting beams 3. The top of the lifting cylinders 2 is connected to the brackets 5. To improve lifting stability, guide mechanisms 6 are designed and installed on the connecting beams 3. Support plates 4 are fixed to the brackets 5 to provide support for the rotating mechanism. Safety stops 7 and switch detection plates 8 provide safety assurance for lifting position control.

[0061] The rotating mechanism includes a flat bearing 9, an inner shaft 10 of a collar, and a lifting plate 11. The lifting plate 11 is a circular flat plate. In practice, the diameter of the lifting plate should be no less than twice the front wheel track, and the thickness of the lifting plate should be no less than 20 mm. The lifting plate 11 has a circular embedded hole in the center. The top of the inner shaft 10 of the collar is embedded in the inner hole of the lifting plate 11 and secured by a ring of countersunk bolts around the perimeter. The flat bearing 9 is embedded in the center of the support plate 4, and the bottom of the inner shaft 10 of the collar is precisely fitted with the flat bearing 9. This allows the lifting plate 11 to rotate relative to the support plate 4 and provides structural support for the front landing gear wheels.

[0062] The locking device includes a mounting plate 12, a torque sensor connecting shaft 13, a clamping cylinder 14, a limit pin 15, a locking disc 16, a connecting disc 17, a detection switch bracket 18, a support 19, a locking nut 20, a drive disc 21, a synchronous belt 22, a drive pulley 23, a driven pulley 24, a pulley connecting shaft 25, a connecting bolt 26, a motor mounting plate 27, and a drive motor 28. The clamping cylinder 14 and the mounting plate 12 are installed at the bottom of the support plate 4. A limit pin 15 is installed at the rod end of the clamping cylinder 14 by screw connection. The extension and retraction of the limit pin by the extension and retraction of the cylinder rod forms a locking mechanism. The limit pin 15 is provided with a cylindrical guide post, which can slide within the guide groove on the mounting plate 12. The limit pin is made of 45 steel and undergoes quenching treatment to improve the structural strength of the part.

[0063] A large-range torque sensor (range 0-10000 N·m) is installed below the center of the lifting plate 11. The upper part of the torque sensor connecting shaft 13 is connected to the torque sensor, and the lower part of the torque sensor connecting shaft 13 is inserted into the center hole of the locking plate 16 and then connected to the drive plate 21 through the connecting plate 17. The locking plate 16 is designed according to the maximum test load. The torque sensor and the connecting shaft 13 are tightly fitted to detect the rotational torque when the machine wheel turns. A pin slot is designed on the locking plate 16 to allow the limit pin 15 to be inserted in the locked state, so as to achieve the clamping and locking of the lifting plate. The locking plate 16 is made of 45 steel.

[0064] Because the lifting plate 11 is locked by a pin, the turntable may rotate randomly after the limit pin 15 disengages from the pin slot. If the test is repeated and the plate needs to be clamped, the limit pin 15 will not be correctly aligned with the pin slot on the locking plate 16. Therefore, to avoid manual reset, a reset mechanism (drive plate 21, synchronous belt 22, drive pulley 23, driven pulley 24, pulley connecting shaft 25, connecting bolt 26, motor mounting plate 27, and drive motor 28) needs to be set in the locking device.

[0065] A motor mounting plate 27 is installed at the top center of the connecting beam 3. A drive motor 28 is installed at the bottom of the motor mounting plate 27. The drive motor 28 serves as the power source for the reset mechanism. The rod end of the drive motor 28 is fixedly connected to the driven wheel 24. According to the reset control command, the drive motor 28 drives the driven wheel to move. The driving wheel 23 is connected to the bottom of the drive disc 21 by bolts. The driven wheel 24 drives the driving wheel 23 to move through the synchronous belt 22, thereby driving the connecting disc 17 fixed in the drive disc to move, and then driving the locking disc 16 connected to the connecting disc 17 to reset to the origin.

Claims

1. An automatic nose landing gear lifting and locking device for an aircraft, characterized in that: The device includes: a landing gear synchronous lifting mechanism, a rotating mechanism, and a locking mechanism; The landing gear synchronous lifting mechanism is installed on the ground and is used to raise or lower the landing gear. The landing gear synchronous lifting mechanism includes: a base, lifting cylinders, a connecting beam, a support plate, and a bracket. Two bases are fixed to the ground, and the connecting beam connects the two bases. Two lifting cylinders are fixed to the two bases respectively. The actuating rods of the lifting cylinders are connected to the bracket. The support plate is fixedly connected to the two brackets. The actuating rods of the two lifting cylinders indirectly drive the support plate to move up and down through the bracket. The rotating mechanism is mounted on the landing gear synchronous lifting mechanism and is used to drive the landing gear to rotate. The rotating mechanism includes a lifting plate, a flat bearing, and an inner shaft of a collar. The lifting plate has a circular embedded hole at its center. The inner shaft of the collar is a two-step shaft, with the top of the inner shaft of the collar embedded in the circular embedded hole of the lifting plate. The inner shaft of the collar is fixed to the lifting plate by countersunk bolts. A flat bearing is embedded in the center of the support plate, and the bottom of the inner shaft of the collar mates with the flat bearing. The locking mechanism is located between the rotating mechanism and the landing gear synchronous lifting mechanism to lock the rotating mechanism and prevent it from rotating arbitrarily. The locking mechanism includes: a torque sensor connecting shaft, a mounting plate, a clamping cylinder, a limit pin, and a locking disc. The mounting plate is installed at the bottom of the support plate, and the clamping cylinder is fixed to the mounting plate. A limit pin is connected to the actuating rod of the clamping cylinder, and the limit pin slides in the guide groove of the mounting plate through the actuation of the clamping cylinder. A torque sensor is installed below the center of the lifting disc, and the lower end of the torque sensor is connected to the torque sensor connecting shaft. The lower end of the torque sensor connecting shaft is inserted into the center hole of the locking disc. The locking disc has a pin slot. The clamping cylinder controls the limit pin to insert into or pull out of the pin slot to achieve circumferential locking and unlocking of the lifting disc.

2. The automatic nose landing gear lifting and locking device for aircraft according to claim 1, characterized in that: The landing gear synchronous lifting mechanism also includes: a guiding mechanism; The end of the connecting beam is provided with a guide mechanism perpendicular to the ground; The bracket has a guide hole, and the bracket is sleeved on the guide mechanism through the guide hole; The guide mechanism guides the up-and-down movement of the support.

3. The automatic nose landing gear lifting and locking device for aircraft according to claim 2, characterized in that: The guide mechanism is provided with a safety stop at its top; the safety stop is used to limit the movement of the support.

4. The automatic nose landing gear lifting and locking device for aircraft according to claim 2, characterized in that: The guide mechanism is equipped with a switch detection plate at its top. The switch detection board is used to lift the hydraulic cylinder to release pressure after detecting that the bracket has moved to its maximum stroke, so as to prevent it from exceeding the stroke.

5. The automatic nose landing gear lifting and locking device for aircraft according to claim 1, characterized in that: The diameter of the lifting plate is not less than twice the front wheel track, and the thickness is not less than 20 mm.

6. The automatic nose landing gear lifting and locking device for aircraft according to claim 1, characterized in that: The locking mechanism further includes: a reset mechanism; The reset mechanism includes: a connecting disc, a drive disc, a synchronous belt, a driving pulley, a driven pulley, a pulley connecting shaft, a motor mounting plate, and a drive motor; After the torque sensor connecting shaft is inserted into the locking disc, the locking disc, connecting disc, drive disc, and drive wheel are mounted on the motor mounting plate through the locking nut and pulley connecting shaft; A motor mounting plate is fixed at the top center of the connecting beam, and the drive motor is installed at the bottom of the motor mounting plate; The output shaft of the drive motor is fixedly connected to the driven wheel, and the driven wheel is connected to the driving wheel through a synchronous belt and drives the driving wheel to rotate; The drive wheel drives the drive disc and connecting disc to rotate, which in turn drives the locking disc to rotate and reset.

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