A large angle folding self-folding lock strut mechanism

Abstract

The application belongs to the field of aircraft structure design, and particularly relates to a large-angle folding self-folding lock support rod mechanism, which comprises a lower support rod, an upper support rod, an actuating cylinder, a lock driving rocker arm, a connecting rocker arm and a switching rocker arm. The end portions of the upper support rod and the lower support rod are hingedly connected to each other, the lower end of the lower support rod is connected to a landing gear through a connecting bolt of a hinged support point O1; the upper end of the lower support rod is connected to the switching rocker arm; the switching rocker arm is hingedly connected to the lower end of the upper support rod through a hinged support point O2; the number of parts is small, the structure is simple, and the main lock mechanism assembly is only 3-4 in addition to the main load bearing support rod, and the structure is light in weight. The lock mechanism assembly of the support rod mechanism is arranged on one side of the support rod, can realize a large-angle folding function, and can be adjusted to be less than 10 degrees through geometric arrangement. The retaining spring of the lock mechanism of the support rod mechanism is a compression spring, and compared with the form of a pull spring adopted by most mechanisms, the compression spring has higher reliability and longer service life.

Description

Technical Field

[0001] The present invention relates to the field of aircraft structure design, and in particular to a large-angle folding self-folding locking strut mechanism. Background Art

[0002] The main function of the landing gear strut mechanism is to support the landing gear so that it will not collapse during landing and taxiing when the landing gear is locked in the lowered position. Secondly, after unlocking, the landing gear can be folded during the retraction process so that the landing gear can be retracted into the landing gear bay.

[0003] In the layout of a certain aircraft landing gear scheme, it was found that the space in the landing gear compartment was relatively small when the landing gear was in the retracted position. This required that the strut mechanism of the landing gear of this type of aircraft should have a larger folding angle after retraction and a smaller landing gear envelope space after folding.

[0004] Therefore, how to increase the folding angle of the landing gear strut mechanism and reduce the landing gear envelope space is a problem that needs to be solved. Summary of the Invention

[0005] The purpose of the present application is to provide a large-angle folding self-folding locking strut mechanism to solve the problem that the existing strut mechanism of the landing gear is difficult to adapt to small spaces.

[0006] The technical solution of the present application is: a large-angle folding self-folding lock strut mechanism, comprising a lower strut, an upper strut, an actuator, a lock drive rocker arm, a connecting rocker arm and a transfer rocker arm;

[0007] The ends of the upper support rod and the lower support rod are hinged to each other, the lower end of the lower support rod is connected to the landing gear through the connecting bolt of the hinge support point O1, and the upper end of the lower support rod is connected to the transfer rocker arm; the transfer rocker arm is hinged to the lower end of the upper support rod through the hinge support point O2, and the upper end of the upper support rod is installed on the body through the connecting bolt of the hinge support point O4; the bottom of the actuator is hinged to the side wall of the upper support rod through the hinge support point O5, and its piston rod is hinged to the hinge support point O6 in the middle of one side of the lock drive rocker arm; one end of the lock drive rocker arm is hinged to the hinge support point O6 in the middle of the lock drive rocker arm; It is hinged to the upper support rod through the hinge point O3, and the other end of the lock-driving rocker arm is hinged to one end of the connecting rocker arm through the hinge point O7; the other end of the connecting rocker arm is hinged to one end of the transfer rocker arm through the hinge point O8; the other end of the transfer rocker arm is hinged to the end of the upper support rod to form a four-bar locking mechanism; when the line connecting the two ends of the lock-driving rocker arm and the intersection position of the connecting rocker arm and the end of the transfer rocker arm reaches a predetermined deflection value K, it constrains the rotation of the upper support rod and the lower support rod in the clockwise and counterclockwise directions.

[0008] Preferably, the actuator is a compression spring actuator.

[0009] Preferably, a cross orthogonal connecting hole is provided on the transfer rocker arm, a fourth rocker arm is connected to the transfer rocker arm, and the other end of the fourth rocker arm is provided with a hole parallel to the hinge point O2.

[0010] Preferably, the connection end connecting the rocker arm and the transfer rocker arm is designed with a limited motion platform.

[0011] Preferably, a semi-box structure is provided on the lock driving rocker arm, and the semi-box structure can block the movement tendency of the lock driving rocker arm under the action of the spring force.

[0012] Preferably, the predetermined deflection value is 7 mm.

[0013] Preferably, the folding angle between the lower support rod and the upper support rod can be less than 10°.

[0014] Preferably, the upper support rod and the lower support rod, the compression spring actuator and the lock drive rocker arm, the lock drive rocker arm and the connecting rocker arm, the connecting rocker arm and the transfer rocker arm, and the hinged positions between the transfer rocker arm and the upper support rod and the lower support rod are all connected by connecting bolts.

[0015] Preferably, the lock driving rocker arm is an open-sided box-type connecting part with parallel holes on the hinge fulcrum O3 and the hinge fulcrum O7, and a parallel hole on the hinge fulcrum O6 in the middle. The back side of the lock driving rocker arm is connected to the compression spring actuator.

[0016] Preferably, an ear piece is provided on the back side of the lock driving rocker arm, and the ear piece is connected to the compression spring actuator cylinder.

[0017] Preferably, the lower support rod is hinged orthogonally to the transfer rocker arm.

[0018] Preferably, the lower support rod and the transfer rocker arm are integrally arranged.

[0019] The large-angle folding self-folding locking strut mechanism of the present application has the following advantages:

[0020] 1. The number of parts is small and the structure is simple. In addition to the main load-bearing support rod, there are only 3-4 main locking mechanism components, and the structure is light.

[0021] 2. The locking mechanism assembly of the strut mechanism is arranged on one side of the strut, which can realize the folding function at a larger angle. The folding angle can be adjusted to within 10° through geometric arrangement.

[0022] 3. The locking mechanism of the support rod mechanism uses a compression spring as the retaining spring. Compared with the tension spring used in most mechanisms, the compression spring has higher reliability and longer service life.

[0023] 4. The folded support rod mechanism has a large folding angle and is compact, so the total volume is small and the space occupied is small. It is easy to use in a small space environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions provided by this application, the following is a brief introduction to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of this application.

[0025] Figure 1 This is a schematic diagram of the structure of the locked load-bearing state for this application;

[0026] Figure 2 This is a schematic diagram of the structure of the application and the unlocked folded state.

[0027] 1. Lower support rod; 2. Upper support rod; 3. Compression spring actuator; 4. Lock drive rocker arm; 5. Connecting rocker arm; 6. Adapter rocker arm; 7. Connecting bolt; 8. Limiting platform; 9. Ear piece. DETAILED DESCRIPTION

[0028] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 making creative efforts are within the scope of protection of the present invention.

[0029] A large-angle folding self-folding locking strut mechanism comprises a lower strut 1, an upper strut 2, an actuator, a lock drive rocker arm 4, a connecting rocker arm 5 and a transfer rocker arm 6. It has two states: locked load-bearing and unlocked folding.

[0030] The ends of the upper strut 2 and lower strut 1 are hinged to each other. The lower end of the lower strut 1 is connected to the landing gear via a connecting bolt 7 at hinge point O1, while the upper end of the lower strut 1 is hinged orthogonally to the transfer rocker arm 6 via bolts. The transfer rocker arm 6 is hinged to the lower end of the upper strut 2 via hinge point O2, while the upper end of the upper strut 2 is mounted to the aircraft body via a connecting bolt 7 at hinge point O4. The bottom of the actuator is hinged to the side wall of the upper strut 2 via hinge point O5, and its piston rod is hinged to the middle of one side of the lock drive rocker arm 4 at hinge point O6. One end of the lock drive rocker arm 4 is hinged to the upper strut 2 via hinge point O3, and the other end of the lock drive rocker arm 4 is hinged to one end of the connecting rocker arm 5 via hinge point O7. The other end of the connecting rocker arm 5 is hinged to one end of the transfer rocker arm 6 via hinge point O8. The other end of the transfer rocker arm 6 is hinged to the end of the upper strut 2, forming a four-bar locking mechanism. When the line connecting the two ends of the lock drive rocker arm 4 and the intersection position of the connecting rocker arm 5 and the end of the transfer rocker arm 6 reaches the predetermined deflection value K, the rotation of the upper support rod 2 and the lower support rod 1 in both clockwise and counterclockwise directions is constrained.

[0031] like Figure 1As shown, the intersection of the connecting rocker arm 5 and the transfer rocker arm 6 is at O8, and the ends of the lock-driving rocker arm 4 are at O3 and O7. The main locking principle is that the intersection O8 lies above the line connecting the intersections O3 and O7, reaching a predetermined deflection value K, forming a dead point for the folding motion of the lower and upper struts 1 and 2. The cleverness of this dead point lies in simultaneously restricting the clockwise and counterclockwise rotation of the lower strut 1 relative to the upper strut 2. The struts cannot fold at this position, bearing the tensile and compressive loads on the line connecting O1 and O4, thus forming a locked load-bearing state.

[0032] Since the clockwise and counterclockwise movement of the lock-driving rocker arm 4 around the intersection of O3 will cause the lock mechanism to open or be in an unfavorable load position. Based on this problem, the actuator uses a compression spring actuator 3. The compression spring actuator 3 is a linear motion component, which can be a hydraulic actuator, an electric actuator, or an actuator with other energy sources. A compression spring is integrated inside, and the spring force keeps the actuator piston rod in an extension trend. The hydraulic or electric drive or other drive only drives the piston rod of the compression spring actuator 3 in a contraction trend. At this time, the unlocking movement of the lock-driving rocker arm 4 is constrained by the compression spring force of the compression spring actuator 3, preventing the clockwise and counterclockwise movement of the upper support rod 2 and the lower support rod 1 from causing the lock mechanism to open or be in an unfavorable load position.

[0033] In order to prevent the lock-driven rocker arm 4 from moving counterclockwise around the intersection of O3, a cross-orthogonal connecting hole is provided on the adapter rocker arm 6, and a fourth rocker arm is connected to the adapter rocker arm 6. The other end of the fourth rocker arm is provided with a hole parallel to the hinge point O2. A limit platform 8 is provided on both the connecting rocker arm 5 and the adapter rocker arm 6. When the lock-driven rocker arm 4 rotates to a certain position, it will be stuck by the limit platform 8, thereby constraining the lock-driven rocker arm 4 to rotate counterclockwise.

[0034] Preferably, a semi-box structure may be provided on the drive rocker arm 4, which can block the movement tendency of the lock drive rocker arm 4 under the action of the spring force to facilitate maintenance and inspection.

[0035] When the landing gear is lowered and the strut is extended and locked, the connecting rocker arm 5 and the transfer rocker arm 6 of the strut locking mechanism are folded into the box of the lock drive rocker arm 4. Point O8 crosses the line connecting points O3 and O7, forming a deflection of about 7mm from the line, entering the geometric self-locking area of ​​the mechanism. The lock drive rocker arm 4 is locked under the spring force of the compression spring actuator 3. Figure 1As shown, the movement of the lock-driving rocker arm 4 under the action of the spring force is precisely blocked by the stopper 8 connecting the rocker arm 5 and the transfer rocker arm 6. The strut locking mechanism is self-locking. When the upper and lower struts 2 and 1 are subjected to tension or compression, the load transmitted to the compression spring actuator 3 is very small, and the resistance of the multiplier spring prevents unlocking, thus reliably locking the struts. The spring of the compression spring actuator 3 always keeps the mechanism locked, resisting the extremely small unlocking load transmitted by the upper and lower struts 1, and preventing the stopper 8 from separating and unlocking under external force disturbances.

[0036] When the landing gear needs to be retracted, the compression spring actuator 3 is driven by hydraulic pressure and begins to contract, overcoming the spring force and friction force to pull the connecting rocker arm 5 to rotate. When point O8 crosses the line connecting points O3 and O7, the limit platform 8 connecting the rocker arm 5 and the transfer rocker arm 6 is also separated, and the strut lock mechanism is unlocked. Under the action of the retraction and extension external force, the upper strut 2 and the lower strut 1 can be folded and retracted. Figure 2 shown.

[0037] When the landing gear is retracted, the folded upper and lower struts 2 and 1 are no longer locked. The force that causes the folding of lower and upper struts 1 and 2 now originates from the external pressure load on the line connecting O1 and O4, rather than from the compression spring actuator 3. The compression spring actuator 3 has two primary functions: first, it shortens and unlocks under hydraulic pressure; second, when hydraulic pressure is absent, the compression spring maintains the actuator's extension tendency with a constant force.

[0038] When the landing gear needs to be lowered, the upper strut 2 and the lower strut 1 are extended under the external force at both ends of the struts, overcoming the spring force of the compression spring actuator 3, until they are fully extended. Point O8 crosses the line connecting points O3 and O7, forming a deflection of about 7mm from the line, and enters the geometric self-locking area of ​​the mechanism again, locking the struts as shown in the figure. Figure 1 shown.

[0039] Depend on Figure 2 It can be seen that the folding angle of the lower support rod 1 and the upper support rod 2 is already about 20 degrees, and its value can be further reduced to within 10° by adjusting the length of the compression spring actuator 3, the lock drive rocker arm 4, the rocker arm, the transfer rocker arm 6 and the positions of the intersection points O2, O3, O5, O6, O7, and O8.

[0040] Preferably, the hinged positions between the upper support rod 2 and the lower support rod 1, the compression spring actuator 3 and the lock drive rocker arm 4, the lock drive rocker arm 4 and the connecting rocker arm 5, the connecting rocker arm 5 and the transfer rocker arm 6, and the transfer rocker arm 6 and the upper support rod 2 and the lower support rod 1 are all connected by connecting bolts 7. By tightening or loosening the nuts on the connecting bolts 7, the tightness of the connection between the upper support rod 2 and the lower support rod 1 can be adjusted.

[0041] Preferably, the lock-driving rocker arm 4 is an open-sided box-type connecting part with parallel holes on the hinge points O3 and O7, and a parallel hole on the hinge point O6 in the middle. The three holes are not in a straight line. The back side of the lock-driving rocker arm 4 is connected to the compression spring actuator 3, while ensuring the width and connection stability, its own weight is relatively small.

[0042] Preferably, a lug 9 is provided on the back side of the lock driving rocker arm 4 , and the lug 9 is connected to the compression spring actuator 3 .

[0043] Preferably, the lower support rod 1 can also be designed as one piece with the transfer rocker arm 6, with the holes at both ends designed to be parallel, and an ear piece 9 and a connecting hole are added to the other end of the transfer rocker arm 6.

[0044] Through the above design, the advantages of this application are as follows:

[0045] 1. The number of parts is small and the structure is simple. In addition to the main load-bearing support rod, there are only 3-4 main locking mechanism components, and the structure is light.

[0046] 2. The locking mechanism assembly of the strut mechanism is arranged on one side of the strut, which can realize the folding function at a larger angle. The folding angle can be adjusted to within 10° through geometric arrangement.

[0047] 3. The locking mechanism of the support rod mechanism uses a compression spring as the retaining spring. Compared with the tension spring used in most mechanisms, the compression spring has higher reliability and longer service life.

[0048] 4. The folded support rod mechanism has a large folding angle and is compact, so the total volume is small and the space occupied is small. It is easy to use in a small space environment.

[0049] Finally, it should be noted that the drawings of the embodiments disclosed in the present invention only involve structures related to the embodiments disclosed in the present invention. Other structures can refer to common designs. In the absence of conflicts, the same embodiment and different embodiments of the present invention can be combined with each other.

[0050] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A large-angle folding self-folding locking strut mechanism, characterized by: It comprises a lower support rod (1), an upper support rod (2), an actuator, a lock drive rocker arm (4), a connecting rocker arm (5) and a transfer rocker arm (6); The ends of the upper support rod (2) and the lower support rod (1) are hinged to each other, the lower end of the lower support rod (1) is connected to the landing gear through the connecting bolt (7) of the hinge support O1, and the upper end of the lower support rod (1) is connected to the transfer rocker arm (6); the transfer rocker arm (6) is hinged to the lower end of the upper support rod (2) through the hinge support O2, and the upper end of the upper support rod (2) is installed on the body through the connecting bolt (7) of the hinge support O4; the bottom of the actuator is hinged to the side wall of the upper support rod (2) through the hinge support O5, and its piston rod is hinged to the hinge support O6 in the middle of one side of the lock drive rocker arm (4); one end of the lock drive rocker arm (4) The lock driving rocker arm (4) is hinged to the upper support rod (2) through the hinge point O3, and the other end of the lock driving rocker arm (4) is hinged to one end of the connecting rocker arm (5) through the hinge point O7; the other end of the connecting rocker arm (5) is hinged to one end of the transfer rocker arm (6) through the hinge point O8; the other end of the transfer rocker arm (6) is hinged to the end of the upper support rod (2) to form a four-link locking mechanism; when the line connecting the two ends of the lock driving rocker arm (4) and the intersection position of the connecting rocker arm (5) and the end of the transfer rocker arm (6) reaches a predetermined deflection value K, the rotation of the upper support rod (2) and the lower support rod (1) in both clockwise and counterclockwise directions is constrained.

2. The large-angle folding self-folding locking strut mechanism according to claim 1, characterized in that: The actuator is a compression spring actuator (3).

3. The large-angle folding self-folding locking strut mechanism according to claim 1, characterized in that: The transfer rocker arm (6) is provided with a cross-orthogonal connection hole, the transfer rocker arm (6) is connected to a fourth rocker arm, and the other end of the fourth rocker arm is provided with a hole parallel to the hinge point O2.

4. The large-angle folding self-folding locking strut mechanism according to claim 1, characterized in that: The connection end of the connecting rocker arm (5) and the transfer rocker arm (6) is designed with a limited motion platform (8).

5. The large-angle folding self-folding locking strut mechanism according to claim 1, characterized in that: A semi-box structure is provided on the lock driving rocker arm (4), and the semi-box structure can block the movement tendency of the lock driving rocker arm (4) under the action of spring force.

6. The large-angle folding self-folding locking strut mechanism according to claim 1, characterized in that: The predetermined deflection value is 7 mm.

7. The large-angle folding self-folding locking strut mechanism according to claim 1, characterized in that: The folding angle of the lower support rod (1) and the upper support rod (2) can be less than 10°.

8. The large-angle folding self-folding locking strut mechanism according to claim 2, characterized in that: The hinged positions between the upper support rod (2) and the lower support rod (1), the compression spring actuator (3) and the lock driving rocker arm (4), the lock driving rocker arm (4) and the connecting rocker arm (5), the connecting rocker arm (5) and the transfer rocker arm (6), and the transfer rocker arm (6) and the upper support rod (2) and the lower support rod (1) are all connected by connecting bolts (7).

9. The large-angle folding self-folding locking strut mechanism according to claim 8, characterized in that: The compression spring inside the compression spring actuator (3) can constrain the unlocking force of the lock driving rocker arm (4); the spring of the compression spring actuator (3) is always locked in the retaining mechanism.

10. The large-angle folding self-folding locking strut mechanism according to claim 1, characterized in that: The lock driving rocker arm (4) is an open-side box-type connection part with parallel holes on the hinge fulcrum O3 and the hinge fulcrum O7, and has a parallel hole on the hinge fulcrum O6 in the middle. The back side of the lock driving rocker arm (4) is connected to the compression spring actuator (3).

11. The large-angle folding self-folding locking strut mechanism according to claim 2, characterized in that: An ear piece (9) is provided on the back side of the lock driving rocker arm (4), and the ear piece (9) is connected to the compression spring actuator cylinder (3).

12. The large-angle folding self-folding locking strut mechanism according to claim 1, characterized in that: The lower support rod (1) is hinged to the transfer rocker arm (6) in an orthogonal manner.

13. The large-angle folding self-folding locking strut mechanism according to claim 1, characterized in that: The lower support rod (1) and the transfer rocker arm (6) are integrally arranged.

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