Landing gear cabin door structure

Abstract

The invention relates to the technical field of undercarriages, in particular to an undercarriage cabin door structure which comprises a first frame, a second frame, a third frame, a fourth frame, a steering engine connector, a second left cabin door hinge connector and a third left cabin door hinge connector. A left cabin door and a right cabin door are fixedly mounted at the lower ends of the first frame, the second frame, the third frame, the fourth frame, the steering engine connector, the second left cabin door hinge connector and the third left cabin door hinge connector; the technical scheme is superior to the prior art in the aspects of system integration level, reliability, maintainability and application range, is suitable for aircrafts with higher requirements on structural lightweight and maintenance convenience, and has good engineering practical value.

Description

Technical Field

[0001] This invention relates to the field of landing gear technology, and more particularly to a landing gear door structure. Background Technology

[0002] The landing gear system is a critical component of aircraft structure. On multi-wheeled, multi-door aircraft or UAVs, the coordinated movement of the landing gear and doors directly affects deployment and recovery efficiency, safety, and system complexity. In existing technologies, aircraft landing gear and doors typically employ a separate control method, driven by their respective electric or hydraulic actuators. The opening and closing of the doors are coordinated using independent servos, linkage mechanisms, or gear pairs. While this structural design offers flexibility and redundancy, it also introduces structural complexity, increased assembly difficulty, and increased system weight, particularly noticeable in small and medium-sized flight platforms or flying-wing UAVs. More critically, the opening / closing of the landing gear and doors relies on multiple control signals and precise timing management. Control system malfunctions or communication delays can lead to safety issues such as landing gear release before the doors are fully open, mechanical conflicts, or even jamming. Furthermore, the parallel operation of multiple systems results in a significant workload for installation, maintenance, and troubleshooting, especially the maintenance of the door drive mechanism within confined spaces.

[0003] Therefore, to overcome these technical obstacles, a more compact, controllable sequence of actions, and simplified drive system integrated landing gear and door linkage solution is needed. Against this backdrop, this invention proposes a landing gear and door linkage structure based on a "single servo drive, multi-stage linkage, and hinged joint constructing a closed mechanical transmission chain," aiming to achieve automatic coordinated linkage between the landing gear and the left and right doors using only a single drive source. This structure not only reduces the overall weight of the aircraft but also improves operational reliability and maintenance convenience, providing a feasible path for the highly integrated landing gear and door structure design of small aircraft. Summary of the Invention

[0004] The purpose of this invention is to solve the technical problems mentioned in the background section.

[0005] The present invention adopts the following technical solution: a landing gear door structure, including frame one, frame two, frame three, frame four, servo joint, left door hinge joint two, and left door hinge joint three, wherein the lower ends of frame one, frame two, frame three, frame four, servo joint, left door hinge joint two, and left door hinge joint three are all fixedly installed with a left door and a right door;

[0006] The lower end of the servo joint is provided with a servo motor, the lower surface of the servo motor is equipped with landing gear, and both sides of the landing gear are equipped with a left cabin door hinge joint.

[0007] It also includes the landing gear mounting base, link one, link two, and link three.

[0008] Preferably, the first frame, the second frame, and the servo motor connector are fixedly connected.

[0009] Preferably, the landing gear mounting base is installed on one side of the landing gear, and the first link, the second link, and the third link are rotatably connected, with the third link and the landing gear being rotatably connected.

[0010] Preferably, it also includes left hatch hinge three, right hatch hinge three, connecting rod four, left hatch hinge one, right hatch hinge one, left hatch hinge two, right hatch hinge two, rocker arm mounting base and pull rod joint.

[0011] Preferably, the left hatch hinge three and the right hatch hinge three are respectively installed on the left hatch and the right hatch, and the connecting rod four is installed between the left hatch hinge three and the right hatch hinge three.

[0012] Preferably, the left hatch hinge 1 and the right hatch hinge 1 are both installed on the inner side of the left hatch hinge joint 1, the left hatch hinge 2 and the right hatch hinge 2 are both installed on the left hatch hinge joint 2, the rocker arm mounting seat is installed on the frame 3, and the pull rod joint is installed on the left hatch hinge 2.

[0013] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0014] This invention achieves automatic coordinated linkage between landing gear extension / retraction and left / right door opening / closing by employing a closed mechanical transmission structure consisting of a single servo motor drive, multi-stage linkages, and hinged joints. Compared to the traditional scheme that uses multiple independent drive devices to control the landing gear and doors, this structure has the following four advantages:

[0015] The structure is more compact, significantly reducing the number of drive components and lowering the overall system weight and installation space requirements;

[0016] The sequence of actions is achieved through adaptive mechanical structure, which simplifies the design of the control system and improves the reliability of action coordination.

[0017] Reduce reliance on electronic control to effectively lower the risk of interference and jamming caused by control failures;

[0018] It is easier to maintain and assemble, making it suitable for flight platforms with limited space and high requirements for lightweight structure.

[0019] In summary, this technical solution is superior to existing technologies in terms of system integration, reliability, maintainability, and applicability. It is suitable for aircraft with high requirements for lightweight structure and ease of maintenance, and has good engineering practical value. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of a landing gear door structure proposed in this invention;

[0021] Figure 2 A rear view schematic diagram of a landing gear door structure is provided for this invention;

[0022] Figure 3 A side view of a landing gear door structure is provided for this invention;

[0023] Figure 4 This is a top view schematic diagram of a landing gear door structure proposed in this invention.

[0024] Legend:

[0025] 1. Servo; 2. Landing gear; 3. Frame 1; 4. Frame 2; 5. Frame 3; 6. Frame 4; 7. Servo connector; 8. Left hatch; 9. Landing gear mount; 10. Link 1; 11. Link 2; 12. Link 3; 13. Left hatch hinge connector 1; 14. Left hatch hinge connector 2; 15. Left hatch hinge connector 3; 16. Right hatch; 17. Left hatch hinge 3; 18. Right hatch hinge 3; 19. Link 4; 20. Left hatch hinge 1; 21. Right hatch hinge 1; 22. Left hatch hinge 2; 23. Right hatch hinge 2; 24. Rocker arm mount; 25. Lever connector. Detailed Implementation

[0026] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described below in conjunction with the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0027] Numerous specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways than those described herein, and therefore the invention is not limited to the specific embodiments disclosed in the following specification.

[0028] Example

[0029] Please see Figure 1-4 The present invention provides a technical solution: a landing gear door structure, including frame 1 3, frame 2 4, frame 3 5, frame 4 6, servo connector 7, left door hinge connector 2 14, and left door hinge connector 3 15. The lower ends of frame 1 3, frame 2 4, frame 3 5, frame 4 6, servo connector 7, left door hinge connector 2 14, and left door hinge connector 3 15 are all fixedly installed with a left door 8 and a right door 16.

[0030] A servo motor 1 is provided at the lower end of the servo motor connector 7. A landing gear 2 is installed on the lower surface of the servo motor 1. A left cabin door hinge connector 13 is installed on both sides of the landing gear 2.

[0031] It also includes landing gear mounting base 9, connecting rod 10, connecting rod 2 11, and connecting rod 3 12;

[0032] The components 1 (3), 2 (4), and servo connector 7 are fixedly connected;

[0033] The landing gear mounting base 9 is installed on one side of the landing gear 2. The first link 10, the second link 11, and the third link 12 are rotatably connected, and the third link 12 is rotatably connected to the landing gear 2.

[0034] It also includes left hatch hinge 317, right hatch hinge 318, connecting rod 419, left hatch hinge 120, right hatch hinge 121, left hatch hinge 22, right hatch hinge 23, rocker arm mounting seat 24, and pull rod joint 25. Left hatch hinge 317 and right hatch hinge 318 are respectively installed on left hatch 8 and right hatch 16. Connecting rod 419 is installed between left hatch hinge 317 and right hatch hinge 318. Left hatch hinge 120 and right hatch hinge 121 are both installed on the inside of left hatch hinge joint 13. Left hatch hinge 22 and right hatch hinge 23 are both installed on left hatch hinge joint 24. Rocker arm mounting seat 24 is installed on frame 35. Pull rod joint 25 is installed on left hatch hinge 22.

[0035] Working Principle: This structure uses a single drive servo motor as its power source and employs multi-stage linkages and hinge joints to construct a closed mechanical transmission chain, achieving the synchronous opening and closing of the landing gear extension and retraction movements and the left and right hatches. Specifically, the drive servo motor drives the landing gear to rotate around a fixed mounting base via a push rod, while the linkage mechanism sequentially transmits motion, causing the left hatch 8 to open in a predetermined sequence. After the left hatch 8 opens, the right hatch 16 is driven to open synchronously via an additional linkage, completing the coordinated movement of both hatches. All key hinge joints and linkages are fixed to the fuselage frame structure, ensuring the stability and precision of the mechanical transmission.

[0036] This solution replaces the traditional multi-servo parallel drive with a mechanical linkage, significantly simplifying the drive system and control logic, and reducing system weight and complexity. Simultaneously, the closed-loop transmission chain ensures reliable execution of the action sequence, reduces reliance on electronic control signals, and improves system safety and maintenance convenience. Its compact overall structure is suitable for space-constrained flight platforms, demonstrating strong practical value and promising prospects for widespread adoption.

[0037] Landing gear lowers and left hatch opens (side view example): servo motor 1 pushes the stick forward, causing landing gear 2 to rotate counterclockwise around landing gear mounting 9. At this time, connecting rod 10 moves with landing gear 2. The moving connecting rod 10 causes connecting rod 21 to rotate counterclockwise around the axis on frame 35. Then connecting rod 312 is driven by connecting rod 21 to cause the pull rod joint 25 on connecting rod 311 to open the left hatch 8.

[0038] Right hatch 16 opens (taking rear view as an example): When left hatch 8 opens, linkage 4 19 moves, causing right hatch hinge 3 18 to move and drive right hatch 16 to open.

[0039] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments for application in other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A landing gear door structure, comprising frame one (3), frame two (4), frame three (5), frame four (6), servo connector (7), left door hinge connector two (14), and left door hinge connector three (15), characterized in that: The lower ends of the following frames (3), (4), (5), (6), (7), (14), and (15) are all fixedly installed with the left hatch (8) and the right hatch (16); The lower end of the servo connector (7) is provided with a servo (1), and the lower surface of the servo (1) is provided with a landing gear (2). Both sides of the landing gear (2) are provided with a left cabin door hinge connector (13). It also includes the landing gear mounting base (9), link one (10), link two (11), and link three (12).

2. The landing gear door structure according to claim 1, characterized in that: The first frame (3), the second frame (4), and the servo connector (7) are fixedly connected.

3. The landing gear door structure according to claim 1, characterized in that: The landing gear mounting base (9) is installed on one side of the landing gear (2), and the connecting rod one (10), connecting rod two (11), and connecting rod three (12) are rotatably connected, and the connecting rod three (12) and the landing gear (2) are rotatably connected.

4. The landing gear door structure according to claim 1, characterized in that: It also includes left hatch hinge three (17), right hatch hinge three (18), linkage four (19), left hatch hinge one (20), right hatch hinge one (21), left hatch hinge two (22), right hatch hinge two (23), rocker arm mounting base (24) and pull rod joint (25).

5. The landing gear door structure according to claim 4, characterized in that: The left hatch hinge three (17) and the right hatch hinge three (18) are respectively installed on the left hatch (8) and the right hatch (16).

6. The landing gear door structure according to claim 4, characterized in that: The left hatch hinge 1 (20) and the right hatch hinge 1 (21) are both installed on the inside of the left hatch hinge joint 1 (13).

7. The landing gear door structure according to claim 4, characterized in that: The fourth link (19) is installed between the left hatch hinge three (17) and the right hatch hinge three (18).

8. The landing gear door structure according to claim 4, characterized in that: The left hatch hinge 2 (22) and the right hatch hinge 2 (23) are both installed on the left hatch hinge joint 2 (14).

9. The landing gear door structure according to claim 4, characterized in that: The rocker arm mounting base (24) is mounted on frame three (5).

10. The landing gear door structure according to claim 4, characterized in that: The pull rod joint (25) is installed on the left cabin door hinge two (22).

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