Low-height rocker arm type undercarriage

Abstract

The invention provides a low-height rocker arm type undercarriage, which belongs to the technical field of aircraft undercarriages, and comprises: a truss support assembly, which comprises a front support rod, a support arm, a support and a side support rod, the front support rod and the support arm are connected to the front end of an undercarriage pillar, and the support and the side support rod are connected to the rear end of the undercarriage pillar, the front supporting rod, the supporting arm, the bracket and the side supporting rod form a truss type bearing structure for supporting the undercarriage supporting column; the bearing assembly comprises an undercarriage supporting column and a lower rocker arm, the undercarriage supporting column is obliquely arranged, the undercarriage supporting column is hinged to the lower rocker arm, and a machine wheel is installed on the lower rocker arm; the folding and unfolding driving assembly comprises a folding and unfolding actuating cylinder, an upper rocker arm, a spring actuating cylinder and a buffer, the upper rocker arm is arranged on the upper side of the undercarriage supporting column and hinged to the folding and unfolding actuating cylinder, the spring actuating cylinder and the buffer, the other end of the spring actuating cylinder is connected to the undercarriage supporting column, and the other end of the buffer is hinged to the lower rocker arm; and the aircraft wheel can be retracted and released by retracting and releasing the actuating cylinder.

Description

Technical Field

[0001] The present application belongs to the technical field of aircraft landing gear, and in particular relates to a low-height rocker-arm landing gear. Background Art

[0002] The aircraft landing gear is usually located on the bottom of the aircraft belly and is stored in the landing gear compartment. In order to store the aircraft landing gear, the aircraft landing gear compartment usually needs to have a high height. As aircraft are developing towards miniaturization and lightness, the space for the aircraft landing gear retractable compartment is becoming increasingly narrow. In the case of extremely narrow space, the aircraft landing gear often needs to be designed with a relatively complex retractable mechanism.

[0003] In order to overcome the problem that the landing gear retraction and extension mechanism is too complicated in a narrow space, a landing gear retraction and extension structure with a relatively simple structure is needed. Summary of the invention

[0004] The object of the present application is to provide a low-height rocker-arm landing gear to solve or alleviate at least one problem in the background technology.

[0005] The technical solution of the present application is: a low-height rocker landing gear, comprising:

[0006] A truss support assembly, the truss support assembly comprising a front strut, a support arm, a bracket and a side strut, the front strut and the support arm having one end connected to the fuselage and the other end connected to the front end of the landing gear strut, the bracket and the side strut having one end connected to the fuselage and the other end connected to the rear end of the landing gear strut, the front strut, the support arm, the bracket and the side strut forming a truss-type bearing structure supporting the landing gear strut;

[0007] A load-bearing assembly, the load-bearing assembly comprises a landing gear strut and a lower rocker arm, the landing gear strut is obliquely arranged, the landing gear strut is hinged to the lower rocker arm, and a wheel is installed on the lower rocker arm;

[0008] A retractable and retractable drive assembly, wherein the retractable and retractable drive assembly comprises a retractable and retractable actuator cylinder, an upper rocker arm, a spring actuator cylinder and a buffer. The upper rocker arm is arranged on the upper side of the landing gear strut and is hinged to the retractable and retractable actuator cylinder, the spring actuator cylinder and the buffer respectively. The other end of the retractable and retractable actuator cylinder is connected to the fuselage, the other end of the spring actuator cylinder is connected to the landing gear strut, and the other end of the buffer is hinged to the lower rocker arm. The upper rocker arm is rotated around the fulcrum of the spring actuator cylinder through the retractable and retractable actuator cylinder, and at the same time, the upper rocker arm drives the buffer to move, so that the lower rocker arm at the end of the buffer is rotated around the rear end of the landing gear strut to realize the retraction and extension of the wheel.

[0009] Preferably, the support arm comprises an upper support arm and a lower support arm, and the upper support arm and the lower support arm are cross-arranged.

[0010] Preferably, the side support rod is arranged at the hinge point between the landing gear strut and the lower rocker arm and the side support rod is arranged transversely.

[0011] Preferably, the bracket is a portal structure, and an opening is provided on one side of the bracket connected to the landing gear strut, and the buffer is arranged in the opening to provide a movement space for the buffer.

[0012] Preferably, the bracket is a triangular structure.

[0013] Preferably, an I-shaped groove is provided on a side of the landing gear strut facing the buffer, and the buffer is arranged in the I-shaped groove.

[0014] Preferably, the angle between the landing gear strut and the horizontal plane is set to 10° to 45°.

[0015] Preferably, the lower rocker arm is a triangular hinge structure, the landing gear struts and wheels are respectively arranged on the hinges on both sides, and the buffer is connected to the middle hinge.

[0016] Preferably, the upper rocker arm is a four-hinge structure, one side of the upper rocker arm is hinged to the landing gear strut, the other side is hinged to the buffer, and the upper side is hinged to the retraction and extension cylinder. The hinge point of the spring actuator cylinder and the upper rocker arm is located between the line connecting the landing gear strut hinge point and the buffer hinge point and the retraction and extension cylinder hinge point and faces the wheel side, so that the upper rocker arm, the buffer and the spring actuator cylinder form a lower lock.

[0017] Preferably, the spring-actuated cylinder comprises an outer cylinder, a piston rod, a compression spring, a floating piston and a plug cap, the outer cylinder is hinged to the landing gear strut, the piston rod is hinged to the upper rocker arm, and the piston rod extends into the outer cylinder and is sealed by the plug cap;

[0018] There is a gap between the piston rod and the outer tube, the compression spring and the floating piston are arranged in the gap and are both installed on the outside of the piston rod, one end of the compression spring is pressed on the piston rod, and the other end is held by the floating piston, and a high-pressure chamber is formed between the floating piston and the plugging cap, and high-pressure gas is introduced into the high-pressure chamber.

[0019] Preferably, the high-pressure gas comprises nitrogen or an inert gas.

[0020] Preferably, there are two spring-actuated cylinders symmetrically arranged on both sides of the upper rocker arm.

[0021] Preferably, a protrusion is provided on the inner side of the upper rocker arm, and the protrusion is arranged at the hinge point between the upper rocker arm and the buffer to support the hinge point.

[0022] Preferably, the height of the protrusion is configured to be lower than the distance from a line connecting a hinge point of an upper landing gear strut of the upper rocker arm and a hinge point of the buffer and the lower rocker arm to a side surface of the upper rocker arm.

[0023] Preferably, it also includes an upper lock assembly, which includes an upper lock bracket and an upper lock. The upper lock bracket is installed on the bracket, and the upper lock is set on the upper lock bracket. When the retractable actuator retracts the wheel to a predetermined position, the upper lock is connected to the buffer 34 or the locking ring on the lower rocker arm.

[0024] The low-height rocker landing gear of the present application has the following advantages:

[0025] 1) Through the lateral connection of the upper and lower double rockers and the fuselage points, the overall configuration of the landing gear is more compact in height, which can realize the layout of the landing gear at a low height. Under load, the change of the landing gear height can be achieved with only a smaller stroke of the buffer under pressure;

[0026] 2) Through the design of upper and lower double rocker arms, the buffer only bears tensile and compressive loads and can shorten the change of landing gear height;

[0027] 3) The mechanism is simple and reliable. The buffer and the upper rocker arm form a strut lock mechanism, which is hidden in the support of the I-beam. The locking mechanism is simple and reliable;

[0028] 4) The double backup compression spring and high pressure chamber are combined to form a tension spring actuator, which fully ensures reliable lowering;

[0029] 5) The retractable actuator can be directly driven to retract without the need for an additional unlocking actuator, making the structure simpler. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solution provided by the present application, the following is a brief introduction to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present application.

[0031] Figure 1 This is a schematic diagram of the low-height rocker-arm landing gear of the present application in the lowered position.

[0032] Figure 2 This is a schematic diagram of the retraction process of the low-altitude rocker arm landing gear of the present application.

[0033] Figure 3 This is a schematic diagram of the low-height rocker-arm landing gear of the present application.

[0034] Figure 4 This is a detailed diagram of the spring actuator in this application.

[0035] Figure 5 This is a schematic diagram of the low-height rocker-arm landing gear of the present application being fully retracted. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solutions and advantages of the implementation of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below in conjunction with the drawings in the embodiments of this application.

[0037] like Figures 1 to 3 As shown, the low-height rocker landing gear provided by the present application includes:

[0038] A truss support assembly, comprising a front strut 11, a support arm 12, a bracket 13 and a side strut 14, wherein one end of the front strut 11 and the support arm 12 are connected to the fuselage and the other end is connected to the front end of the landing gear strut 21, and one end of the bracket 13 and the side strut 14 are connected to the fuselage and the other end is connected to the rear end of the landing gear strut 21, and the front strut 11, the support arm 12, the bracket 13 and the side strut 14 form a truss-type bearing structure supporting the landing gear strut 21;

[0039] The bearing assembly includes a landing gear strut 21 and a lower rocker arm 22. The landing gear strut 21 is arranged obliquely at a large angle (i.e., at a large angle to the vertical direction), and forms an angle θ with the horizontal. The landing gear strut 21 is hinged to the lower rocker arm 22, and a wheel 50 is installed on the lower rocker arm 22.

[0040] The retracting and extending driving assembly includes a retracting and extending actuator cylinder 31, an upper rocker arm 32, a spring actuator cylinder 33 and a buffer 34. The upper rocker arm 32 is arranged on the upper side of the landing gear strut 21 and is hinged to the retracting and extending actuator cylinder 31, the spring actuator cylinder 33 and the buffer 34 respectively. The other end of the retracting and extending actuator cylinder 31 is connected to the fuselage, the other end of the spring actuator cylinder 33 is connected to the landing gear strut 21, and the other end of the buffer 34 is hinged to the lower rocker arm 22. The upper rocker arm 32 is rotated around the fulcrum of the spring actuator cylinder 33 through the retracting and extending actuator cylinder 31, and at the same time, the upper rocker arm 32 drives the buffer 34 to move, so that the lower rocker arm 22 at the end of the buffer 34 is rotated around the rear end of the landing gear strut 21, thereby realizing the retraction and extension of the wheel 50.

[0041] In some embodiments of the present application, the support arm 12 includes an upper support arm 121 and a lower support arm 122 , and the upper support arm 121 and the lower support arm 122 are cross-arranged. The cross-arranged upper support arm 121 and the lower support arm 122 can make the landing gear strut 21 more stable.

[0042] In some embodiments of the present application, the side support rod 14 is arranged at the hinge point between the landing gear strut 21 and the lower rocker arm 22, and is arranged horizontally, that is, the side support rod 14 is roughly perpendicular to the landing gear movement plane, thereby providing lateral support for the landing gear strut 21.

[0043] In some embodiments of the present application, the bracket 13 is a gantry structure, and an opening is provided on one side of the side connected to the landing gear strut 21, and the buffer 34 is arranged in the opening, thereby providing space for the movement of the buffer 34. Further, the bracket 13 is generally a triangular structure, and the vertex of the open end is connected to the landing gear strut 21, and the other two vertices are connected to the fuselage.

[0044] In some embodiments of the present application, an I-shaped groove is provided on the side of the landing gear strut 21 facing the buffer 34, and the buffer 34 is hidden in the I-shaped groove to save space. Further, the angle θ between the landing gear strut 21 and the horizontal plane can be set to 10° to 45°, and the specific angle can be determined according to the stowed height of the landing gear.

[0045] In some embodiments of the present application, the lower rocker arm 22 is a triangular hinge structure, the landing gear strut 21 and the wheel 50 are respectively arranged on the hinges on both sides, and the buffer 34 is connected to the middle hinge.

[0046] like Figure 4 As shown, the upper rocker arm 32 is a four-hinged structure, with its left side hinged to the landing gear strut 21, the right side hinged to the buffer 34, and the upper side hinged to the retracting and extending cylinder 31, and the hinge point of the spring actuator 33 and the upper rocker arm 32 is located between the line connecting the hinge point of the landing gear strut and the hinge point of the buffer and the hinge point of the retracting and extending cylinder, and the hinge point of the spring actuator faces the side of the wheel 50. Thus, the upper rocker arm 32, the buffer 34 and the spring actuator 33 can form a lower lock, and the retracting and extending cylinder 31 can directly drive the upper rocker arm 34 to achieve locking, and can directly drive the upper rocker arm 32 to retract the landing gear, without the need to configure an additional unlocking mechanism or actuator.

[0047] The spring actuator 33 includes an outer cylinder 331, a piston rod 332, a compression spring 333, a floating piston 334 and a plug cap 335. The outer cylinder 331 is hinged to the landing gear strut 21, the piston rod 332 is hinged to the upper rocker arm 32, and the piston rod 332 extends into the outer cylinder 331 and is blocked by the plug cap 335. There is a gap between the piston rod 332 and the outer cylinder 331, and the compression spring 333 and the floating piston 334 are arranged in the gap, and both are installed on the outside of the piston rod 332. One end of the compression spring 333 is pressed on the piston rod 332, and the other end is held by the floating piston 334. A high-pressure chamber A is formed between the floating piston 334 and the plug cap 335, and high-pressure gas can be introduced into the high-pressure chamber. Through the compression spring 333 and the high-pressure chamber A, the spring actuator 33 can output the pulling load better.

[0048] In some embodiments of the present application, nitrogen or inert gas may be introduced into the high-pressure chamber A to improve the safety of the spring actuator 33 .

[0049] In the preferred embodiment of the present application, there are two spring actuators 33, which are symmetrically arranged on both sides of the upper rocker arm 32. One spring actuator 33 is sufficient to fix the landing gear in the lowered position, that is, arranging two spring actuators 33 can form a double backup without the need for additional energy.

[0050] In some embodiments of the present application, a protrusion 321 is provided on the inner side of the upper rocker arm 32, and the protrusion 321 is arranged at the hinge point of the upper rocker arm 32 and the buffer 34 to support the hinge point, wherein the height of the protrusion 321 is configured to be slightly lower than the distance from the line connecting the hinge point of the landing gear strut on the upper rocker arm 32 and the hinge point of the buffer and the lower rocker arm to the side of the upper rocker arm 32, thereby forming a locking mechanism with a small deflection. When the landing gear is lowered, the upper rocker arm 32 and the buffer 34 approximately form a straight line.

[0051] In addition, the low-height rocker landing gear of the present application also includes an upper lock assembly, which includes an upper lock bracket 41 and an upper lock 42. The upper lock bracket 41 is installed on the bracket 13, and the upper lock 42 is set on the upper lock bracket 41. When the retracting cylinder 31 retracts the wheel 50 to a predetermined position, the upper lock 42 is connected to the buffer 34 or the locking ring on the lower rocker arm 22, thereby realizing the locking of the landing gear. The upper lock assembly of the present application does not require additional connection points to be set on the fuselage.

[0052] like Figure 5 The dashed line in the middle shows the retractable space of the landing gear. When the low-height rocker type landing gear of the present application is retracted, the retractable actuator 31 drives the upper rocker arm 32 to drive the buffer 34 to move, and the buffer 34 drives the lower rocker arm 22 to rotate around the lower end of the landing gear strut 21, thereby retracting the landing gear, and the retractable space of the landing gear is narrow. The opposite is true when the landing gear is lowered.

[0053] During the retracting and extending process of the landing gear, the buffer 34 is mainly subjected to pressure. During the compression process, the upper rocker arm 32 is driven to rotate clockwise and stopped by the landing gear strut 21. During the tension process of the buffer 34, the spring actuator 33 is stabilized in the lowered position. Since the deflection of the upper rocker arm 5 and the buffer 34 is very small, the spring actuator 13 can firmly fix the landing gear in the lowered position. When approaching the lowered position, the spring actuator 33 helps to lower the landing gear, and when approaching the retracted position, the spring actuator 33 helps to retract the landing gear. The smaller compression stroke of the buffer 34 can form a larger displacement of the wheel 50 in the vertical stroke.

[0054] The low-height rocker landing gear of the present application has the following advantages:

[0055] 1) Through the lateral connection of the upper and lower double rockers and the fuselage points, the overall configuration of the landing gear is more compact in height, which can realize the layout of the landing gear at a low height. Under load, the change of the landing gear height can be achieved with only a smaller stroke of the buffer under pressure;

[0056] 2) Through the design of upper and lower double rocker arms, the buffer only bears tensile and compressive loads and can shorten the change of landing gear height;

[0057] 3) The mechanism is simple and reliable. The buffer and the upper rocker arm form a strut lock mechanism, which is hidden in the support of the I-beam. The locking mechanism is simple and reliable;

[0058] 4) The double backup compression spring and high pressure chamber are combined to form a tension spring actuator, which fully ensures reliable lowering;

[0059] 5) The retractable actuator can be directly driven to retract without the need for an additional unlocking actuator, making the structure simpler.

[0060] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A low-height rocker landing gear, characterized in that: include: A truss support assembly, the truss support assembly comprising a front strut, a support arm, a bracket and a side strut, the front strut and the support arm having one end connected to the fuselage and the other end connected to the front end of the landing gear strut, the bracket and the side strut having one end connected to the fuselage and the other end connected to the rear end of the landing gear strut, the front strut, the support arm, the bracket and the side strut forming a truss-type bearing structure supporting the landing gear strut; A load-bearing assembly, the load-bearing assembly comprises a landing gear strut and a lower rocker arm, the landing gear strut is obliquely arranged, the landing gear strut is hinged to the lower rocker arm, and a wheel is installed on the lower rocker arm; A retractable and retractable drive assembly, wherein the retractable and retractable drive assembly comprises a retractable and retractable actuator cylinder, an upper rocker arm, a spring actuator cylinder and a buffer. The upper rocker arm is arranged on the upper side of the landing gear strut and is hinged to the retractable and retractable actuator cylinder, the spring actuator cylinder and the buffer respectively. The other end of the retractable and retractable actuator cylinder is connected to the fuselage, the other end of the spring actuator cylinder is connected to the landing gear strut, and the other end of the buffer is hinged to the lower rocker arm. The upper rocker arm is rotated around the fulcrum of the spring actuator cylinder through the retractable and retractable actuator cylinder, and at the same time, the upper rocker arm drives the buffer to move, so that the lower rocker arm at the end of the buffer is rotated around the rear end of the landing gear strut to realize the retraction and extension of the wheel.

2. The low-profile rocker landing gear according to claim 1, characterized in that: The support arm comprises an upper support arm and a lower support arm, and the upper support arm and the lower support arm are cross-arranged.

3. The low-profile rocker arm landing gear according to claim 1, characterized in that: The side support rod is arranged at the hinge point of the landing gear strut and the lower rocker arm and the side support rod is arranged transversely.

4. The low-profile rocker landing gear according to claim 1, characterized in that: The bracket is a portal structure, and an opening is provided on one side of the bracket connected to the landing gear strut. The buffer is arranged in the opening to provide a movement space for the buffer.

5. The low-profile rocker landing gear according to claim 4, characterized in that: The bracket is a triangular structure.

6. The low-profile rocker landing gear according to claim 1, characterized in that: An I-shaped groove is provided on one side of the landing gear strut facing the buffer, and the buffer is arranged in the I-shaped groove.

7. The low-profile rocker-arm landing gear according to claim 6, characterized in that: The angle between the landing gear strut and the horizontal plane is set to 10° to 45°.

8. The low-profile rocker-arm landing gear according to claim 1, characterized in that: The lower rocker arm is a triangular hinge structure, the landing gear struts and wheels are respectively arranged on the hinges on both sides, and the buffer is connected to the middle hinge.

9. The low-profile rocker-arm landing gear according to claim 1, characterized in that: The upper rocker arm is a four-hinge structure, one side of the upper rocker arm is hinged to the landing gear strut, the other side is hinged to the buffer, and the upper side is hinged to the retraction and extension cylinder. The hinge point of the spring actuator cylinder and the upper rocker arm is located between the line connecting the landing gear strut hinge point and the buffer hinge point and the retraction and extension cylinder hinge point and faces the wheel side, so that the upper rocker arm, the buffer and the spring actuator cylinder form a lower lock.

10. The low-profile rocker-arm landing gear according to claim 1, characterized in that: The spring-actuated cylinder comprises an outer cylinder, a piston rod, a compression spring, a floating piston and a plug cap. The outer cylinder is hinged to the landing gear strut, the piston rod is hinged to the upper rocker arm, and the piston rod extends into the outer cylinder to be blocked by the plug cap. There is a gap between the piston rod and the outer tube, the compression spring and the floating piston are arranged in the gap and are both installed on the outside of the piston rod, one end of the compression spring is pressed on the piston rod, and the other end is held by the floating piston, and a high-pressure chamber is formed between the floating piston and the plugging cap, and high-pressure gas is introduced into the high-pressure chamber.

11. The low-profile rocker-arm landing gear according to claim 10, characterized in that: The high pressure gas includes nitrogen or an inert gas.

12. The low-profile rocker-arm landing gear according to claim 10, characterized in that: There are two spring actuators which are symmetrically arranged on both sides of the upper rocker arm.

13. The low-profile rocker-arm landing gear according to claim 9, characterized in that: A protrusion is arranged on the inner side of the upper rocker arm, and the protrusion is arranged at the hinge point between the upper rocker arm and the buffer to support the hinge point.

14. The low-profile rocker-arm landing gear according to claim 13, characterized in that: The height of the protrusion is configured to be lower than the distance from the line connecting the hinge point of the landing gear strut on the upper rocker arm, the buffer and the hinge point of the lower rocker arm to the side surface of the upper rocker arm.

15. The low-profile rocker landing gear according to claim 1, characterized in that: It also includes an upper lock assembly, which includes an upper lock bracket and an upper lock. The upper lock bracket is installed on the bracket, and the upper lock is set on the upper lock bracket. When the retractable actuator retracts the wheel to a predetermined position, the upper lock is connected to the buffer 34 or the locking ring on the lower rocker arm.

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