Rocker arm type undercarriage, aircraft and method

Abstract

The invention provides a rocker arm type undercarriage, an aircraft and a method. The rocker arm type undercarriage comprises a supporting rod, a retractable actuating cylinder, a connecting rod, a buffer mechanism, a skid and a follow-up actuating cylinder used for locking the undercarriage at any position, one end of the supporting rod is hinged to one end of the buffer mechanism, and the other end of the buffer mechanism is hinged to the skid. One end of the folding and unfolding actuating cylinder is hinged to the supporting rod, one end of the connecting rod is hinged to and slides on the buffering mechanism, one end of the follow-up actuating cylinder is hinged to the supporting rod, and the hinge point of the follow-up actuating cylinder and the supporting rod is located below the hinge point of the folding and unfolding actuating cylinder and the supporting rod; the other end of the supporting rod, the other end of the retractable actuating cylinder, the other end of the connecting rod and the other end of the follow-up actuating cylinder are all provided with connecting points E used for being hinged to a machine body. The aircraft can stably take off and land in a complex terrain environment, and the take-off and landing capacity and the bearing capacity of small and medium-sized aircrafts in the complex terrain are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of aircraft, and particularly to a rocker-type landing gear, an aircraft and a method. Background Art

[0002] Most of the landing gears of existing vertical takeoff and landing devices adopt wheeled and skid-type structures. Among them, the wheeled structure has high requirements for the flatness of the takeoff and landing sites and high requirements for the stability of the ship deck during landing. In case of emergency, a temporary landing pad needs to be established, or it has to land at a relatively far airport, which affects the real-time performance and environmental adaptability of mission execution and has poor adaptability for takeoff and landing in complex environments such as mountains, deserts, and beaches.

[0003] The skid-type structure usually uses an arched beam to be rigidly connected to the fuselage. Its load-bearing capacity is limited, and its deformation is restricted by the constraints of the external structure, resulting in limited shock absorption and impact energy absorption capabilities. In addition, the existing skid-type landing gears generally cannot be retracted, which increases the aerodynamic drag during flight and reduces the flight efficiency.

[0004] With the rapid development of the aircraft industry, the demand for takeoff and landing tasks in complex terrains such as mountains, deserts, and beaches is increasing day by day, which puts forward higher requirements for the takeoff and landing capabilities and adaptability to complex terrains of aircraft landing gears, and at the same time, the requirements for the load-bearing capacity of landing gears are also getting higher and higher. Summary of the Invention

[0005] The purpose of the present invention is to provide a rocker-type landing gear, an aircraft and a method that can take off and land smoothly in the environment of complex terrains, and improve the takeoff and landing capabilities and load-bearing capacities of small and medium-sized aircraft in complex terrains.

[0006] The technical solution of the present invention is: a rocker-type landing gear, including a strut, a retraction and extension actuator, a connecting rod, a buffer mechanism, a skid, and a follow-up actuator for locking the landing gear at any position. One end of the strut is hinged to one end of the buffer mechanism, the other end of the buffer mechanism is hinged to the skid, one end of the retraction and extension actuator is hinged to the strut, one end of the connecting rod is hinged and slides on the buffer mechanism, one end of the follow-up actuator is hinged to the strut, and the hinge point of the follow-up actuator and the strut is located below the hinge point of the retraction and extension actuator and the strut; the other ends of the strut, the retraction and extension actuator, the connecting rod, and the follow-up actuator are all provided with connection points E for hinging with the fuselage.

[0007] Preferably, the buffer mechanism includes a strut, a buffer and a rocker arm. One end of the strut is hinged to the brace, and the other end of the strut is hinged to one end of the rocker arm to form a hinge point B. The other end of the rocker arm is hinged to the skid to form a hinge point C. One end of the buffer is hinged to the strut to form a hinge point A, and the other end of the buffer is hinged to the rocker arm to form a hinge point D. The hinge point A, the hinge point B, the hinge point C and the hinge point D are on the same plane.

[0008] Preferably, the rocker-type landing gear further includes a pneumatic actuator hinged between the buffer mechanism and the skid.

[0009] Preferably, a mechanical lock for locking the landing gear in the lowered position is provided inside the retraction actuator.

[0010] Preferably, a hydraulic lock for locking the landing gear at any position is provided inside the follow-up actuator.

[0011] The present invention also provides an aircraft, including a fuselage with a cabin and the above-mentioned rocker-type landing gear, and the connection point E is installed at the corresponding position of the fuselage.

[0012] The present invention also provides a method for retracting and extending the landing gear, which is carried out by using the above-mentioned aircraft, and includes:

[0013] Method for retracting the landing gear:

[0014] Unlock the follow-up actuator, start the retraction actuator to extend, push the brace to rotate upward relative to the fuselage around the axis hinged to the fuselage, drive the buffer mechanism to rise, and at the same time push the follow-up actuator to follow and contract in the direction hinged to the fuselage; when the buffer mechanism rises, drive the connecting rod to follow and rotate upward around the axis hinged to the fuselage, and the skid moves together with the buffer mechanism until the retraction actuator is fully extended, and the rocker-type landing gear is lifted into the cabin as a whole; lock the follow-up actuator.

[0015] Method for lowering the landing gear:

[0016] Unlock the follow-up actuator, start the retraction actuator to retract, pull the brace to rotate downward relative to the fuselage around the axis hinged to the fuselage, drive the buffer mechanism to descend, and at the same time pull the follow-up actuator to follow and extend in the direction hinged to the brace; when the buffer mechanism descends, drive the connecting rod to follow and rotate downward around the axis hinged to the fuselage until the skid of the rocker-type landing gear lands; lock the follow-up actuator.

[0017] The present invention also provides a method for adjusting the landing attitude of the landing gear, which is carried out by using the above-mentioned aircraft, and includes:

[0018] Obtain the landing attitude of the aircraft. If the landing attitude exceeds the critical value, unlock the follow-up actuator, drive the follow-up actuator to actuate for the second time, make it extend to push down the strut or retract to pull up the strut, so that the strut rotates upward or downward around the axis hinged to the fuselage, drive the buffer mechanism to descend or ascend, adjust the vertical height of the landing gear, and perform secondary adjustment on the aircraft's parking attitude.

[0019] Preferably, when landing, the lower end of the skid first bears the gravity, causing the skid to rotate around the axis hinged to the buffer mechanism, and the pneumatic actuator compresses until the skid is completely grounded.

[0020] Preferably, if there is a slope on the ground where the skid contacts after the landing gear lands and stops, it drives the skid to adaptively continue to rotate, causing the pneumatic actuator to compress further until the skid is completely in contact with the slope surface.

[0021] Compared with the related technology, the beneficial effects of the present invention are as follows:

[0022] First, the present invention adds a follow-up actuator, which can actuate the landing gear for the second time, can adjust the vertical height of the landing gear, realize the secondary adjustment of the aircraft's parking attitude, and has a large vertical height adjustment range, can adapt to takeoff and landing on slopes in a large range, expand the aircraft mission execution area, and meet the emergency takeoff, landing and load-bearing requirements of small and medium-sized aircraft on complex terrains such as grasslands, snowfields, beaches, and deserts;

[0023] Second, the rocker-type landing gear adopts a double-rocker four-bar mechanism. By increasing the lever arm of the output force of the retraction and extension actuator, the driving force of the retraction and extension actuator of the landing gear is reduced, thereby reducing the weight of the landing gear;

[0024] Third, the newly added follow-up actuator in the present invention can be locked at any predetermined position, and can act as a strut of the landing gear to bear the load after locking, thereby improving the load-bearing capacity and stability of the landing gear;

[0025] Fourth, the follow-up actuator is internally provided with a hydraulic lock, and a mechanical lock is arranged in the retraction and extension actuator, which improves the reliability of the landing gear's lowered position locking. Before landing, the follow-up actuator can be unlocked to actuate, and the retraction and extension actuator can be reversely judged whether it is reliably locked to improve the reliability and safety of the landing gear's lowered position locking;

[0026] Fifth, the rocker-type landing gear is additionally provided with a pneumatic actuator, which enables the skid to realize self-adaptive adjustment during the landing of the landing gear, improves the takeoff and landing ability of the landing gear on complex terrains, and expands the application scenarios of the landing gear;

[0027] Sixth, optimize the structure of the buffer mechanism. When the vertical height of the landing gear is adjusted, the maximum distance of the connection axis between the skid and the buffer mechanism moving along the heading (front and back) is relatively small, reasonably controlling the heading movement range of the landing gear when adjusting the attitude on complex terrains, and improving the reliability of the secondary adjustment of the landing gear's secondary landing attitude. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 FIG. 5 is a schematic structural view of the rocker-type landing gear provided by the present invention in a fully lowered and loaded state;

[0029] Figure 2 FIG. 6 is a schematic structural view of the rocker-type landing gear provided by the present invention in a semi-retracted and loaded state;

[0030] Figure 3 FIG. 7 is a schematic structural view of the rocker-type landing gear provided by the present invention in a state of the highest load-bearing position;

[0031] Figure 4 FIG. 8 is a schematic view of the rocker-type landing gear provided by the present invention in a fully retracted state.

[0032] In the drawings: 1, strut; 2, buffer mechanism; 3, skid; 4, retraction actuator; 5, connecting rod; 6, follow-up actuator; 7, pneumatic actuator; 8, strut; 9, buffer; 10, rocker arm. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] The present invention will be described in detail below with reference to the drawings and in conjunction with embodiments. It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other. For the convenience of description, words such as "upper", "lower", "left", and "right" hereinafter only represent the same directions as the upper, lower, left, and right directions of the drawings themselves, and do not limit the structure.

[0034] As Figure 1 shown, a rocker-type landing gear provided in this embodiment includes a strut 1, a buffer mechanism 2, a skid 3, a retraction actuator 4, a connecting rod 5, a follow-up actuator 6, and a pneumatic actuator 7.

[0035] The lower end of the strut 1 is hinged to the upper end of the buffer mechanism 2, the lower end of the buffer mechanism 2 is hinged to the skid 3, the lower end of the retraction actuator 4 is hinged to the strut 1, and the lower end of the connecting rod 5 is hinged to the buffer mechanism 2. The strut 1 and the connecting rod 5 form a double rocker arm of the landing gear. The lower end of the follow-up actuator 6 is hinged to the strut 1. The hinge point of the follow-up actuator 6 and the strut 1 is located below the hinge point of the retraction actuator 4 and the strut 1. Both ends of the pneumatic actuator 7 are respectively hinged to the upper end of the skid 3 and the lower end of the buffer mechanism 2. Connection points E for hinging with the fuselage are provided at the upper ends of the strut 1, the retraction actuator 4, the connecting rod 5, and the follow-up actuator 6.

[0036] As Figure 2As shown, the buffer mechanism 2 includes a support column 8, a buffer 9 and a rocker arm 10. One end of the support column 8 is hinged to the strut 1, and the other end of the support column 8 is hinged to one end of the rocker arm 10 to form a hinge point B. The other end of the rocker arm 10 is hinged to the skid 3 to form a hinge point C. One end of the buffer 9 is hinged to the support column 8 to form a hinge point A, and the other end of the buffer 9 is hinged to the rocker arm 10 to form a hinge point D. The hinge points A, B, C and D are on the same plane.

[0037] The retraction and extension actuating cylinder 4 provides the operating force for the retraction and extension of the landing gear, and a mechanical lock is arranged inside for locking the landing gear in the lowered position.

[0038] The follow-up actuating cylinder 6 is internally provided with a hydraulic lock, which can lock the landing gear at any position, has sufficient strength, and can withstand the impact load when the landing gear lands.

[0039] The present invention also provides an aircraft, including a fuselage with a cabin and the above-mentioned rocker arm type landing gear, and the connection points E on the strut 1, the retraction and extension actuating cylinder 4, the connecting rod 5 and the follow-up actuating cylinder 6 are installed at corresponding positions of the fuselage.

[0040] The present invention also provides a method for retracting and extending the landing gear, which is carried out by using the above-mentioned aircraft, and includes:

[0041] Method for retracting the landing gear:

[0042] As Figure 2 shown, unlock the follow-up actuating cylinder 6, start the retraction and extension actuating cylinder 4 to extend, push the strut 1 to rotate upward relative to the fuselage around the axis hinged to the fuselage, drive the buffer mechanism 2 to rise, and at the same time push the follow-up actuating cylinder 6 to follow and contract in the direction of being hinged to the fuselage; when the buffer mechanism 2 rises, drive the connecting rod 5 to rotate upward following around the axis hinged to the fuselage, and the skid 3 moves together with the buffer mechanism 2 until the retraction and extension actuating cylinder 4 is fully extended, and the rocker arm type landing gear is integrally lifted into the cabin (as Figure 4 shown); lock the follow-up actuating cylinder 6.

[0043] Method for lowering the landing gear:

[0044] As Figure 1 shown, unlock the follow-up actuating cylinder 6, start the retraction and extension actuating cylinder 4 to retract, pull the strut 1 to rotate downward relative to the fuselage around the axis hinged to the fuselage, drive the buffer mechanism 2 to descend, and at the same time pull the follow-up actuating cylinder 6 to follow and extend in the direction of being hinged to the strut 1; when the buffer mechanism 2 descends, drive the connecting rod 5 to rotate downward following around the axis hinged to the fuselage until the skid 3 of the rocker arm type landing gear lands; lock the follow-up actuating cylinder 6.

[0045] The present invention also provides a method for adjusting the landing attitude of a landing gear, which is carried out by using the above-mentioned aircraft, and includes:

[0046] Obtain the landing attitude of the aircraft. If the landing attitude exceeds the critical value, unlock the servo actuator 6, drive the servo actuator 6 to actuate for the second time, so that it extends to push down the strut 1 or retracts to pull up the strut 1, causing the strut 1 to rotate upward or downward around the axis hinged to the fuselage, driving the buffer mechanism 2 to descend or ascend, adjusting the vertical height of the landing gear, and performing a secondary adjustment on the parking attitude of the aircraft to adapt to landings on different slopes (such as Figure 3 shown).

[0047] During landing, the lower end of the skid 3 first bears the gravity, causing the skid 3 to rotate around the axis hinged to the buffer mechanism 2, and the pneumatic actuator 7 compresses until the skid 3 is completely grounded.

[0048] If there is a slope on the ground where the skid 3 contacts after the landing gear stops landing, it drives the skid 3 to adaptively continue to rotate, causing the pneumatic actuator 7 to compress further until the skid 3 is completely in contact with the slope surface.

[0049] When the servo actuator 6 adjusts the vertical height of the landing gear, the maximum distance that the connecting shaft of the skid 3 and the buffer mechanism 2 moves in the heading direction (forward and backward) is relatively small.

[0050] The above are only embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structural or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be similarly included in the patent protection scope of the present invention.

Claims

1. A rocker landing gear, comprising a strut (1), a retractable actuator (4), a connecting rod (5), a buffer mechanism (2) and a sled (3), wherein one end of the strut (1) is hinged to one end of the buffer mechanism (2), the other end of the buffer mechanism (2) is hinged to the sled (3), one end of the retractable actuator (4) is hinged to the strut (1), one end of the connecting rod (5) is hinged to and slides on the buffer mechanism (2), characterized in that: It also includes a follower actuator cylinder (6) for locking the landing gear at any position, one end of the follower actuator cylinder (6) is hinged on the strut (1), and the hinge point between the follower actuator cylinder (6) and the strut (1) is located below the hinge point between the retractable actuator cylinder (4) and the strut (1); the other end of the strut (1), the other end of the retractable actuator cylinder (4), the other end of the connecting rod (5) and the other end of the follower actuator cylinder (6) are all provided with a connection point E for hinged connection with the fuselage.

2. The rocker arm landing gear according to claim 1, characterized in that: The buffer mechanism (2) comprises a support (8), a buffer (9) and a rocker arm (10), one end of the support (8) is hinged to the strut (1), the other end of the support (8) is hinged to one end of the rocker arm (10) to form a hinge point B, the other end of the rocker arm (10) is hinged to the sled (3) to form a hinge point C, one end of the buffer (9) is hinged to the support (8) to form a hinge point A, the other end of the buffer (9) is hinged to the rocker arm (10) to form a hinge point D, and the hinge points A, B, C and D are on the same plane.

3. The rocker arm landing gear according to claim 1, characterized in that: It also includes a pneumatic actuator (7) hinged between the buffer mechanism (2) and the slide (3).

4. The rocker arm landing gear according to claim 3, characterized in that: A mechanical lock for locking the landing gear in the lowered position is arranged inside the retractable actuator cylinder (4).

5. The rocker arm landing gear according to any one of claims 1 to 4, characterized in that: A hydraulic lock for locking the landing gear at any position is arranged in the follower actuator cylinder (6).

6. An aircraft comprising a fuselage having a cabin, characterized in that: It also includes the rocker arm landing gear as described in any one of claims 1 to 5, wherein the connection point E is installed at a corresponding position of the fuselage.

7. A landing gear retraction and extension method, performed using the aircraft according to claim 6, comprising: Landing gear retraction method: Unlock the follower actuator cylinder (6), start the retracting actuator cylinder (4) to extend, push the support rod (1) to rotate upward relative to the fuselage around the axis of the hinge with the fuselage, and drive the buffer mechanism (2) to rise, and at the same time push the follower actuator cylinder (6) to shrink in the direction of the hinge with the fuselage; when the buffer mechanism (2) rises, it drives the connecting rod (5) to rotate upward around the axis of the hinge with the fuselage, and the slide (3) moves together with the buffer mechanism (2) until the retracting actuator cylinder (4) is fully extended and the rocker landing gear is lifted into the cabin as a whole; lock the follower actuator cylinder (6); Landing gear lowering method: Unlock the follower actuator cylinder (6), start the retracting of the retracting actuator cylinder (4), pull the support rod (1) to rotate downward relative to the fuselage around the axis hinged to the fuselage, drive the buffer mechanism (2) to descend, and at the same time pull the follower actuator cylinder (6) to extend in the direction of the hinge with the support rod (1); when the buffer mechanism (2) descends, it drives the connecting rod (5) to rotate downward around the axis hinged to the fuselage until the skid (3) of the rocker landing gear lands; lock the follower actuator cylinder (6).

8. A method for adjusting landing gear landing attitude, using the aircraft as claimed in claim 6, characterized in that: include: The landing attitude of the aircraft is obtained. If the landing attitude exceeds a critical value, the follower actuator cylinder (6) is unlocked and driven to perform a secondary actuation, so that the follower actuator cylinder (6) is extended to push down the support rod (1) or retract to pull up the support rod (1), so that the support rod (1) rotates upward or downward around the axis hinged to the fuselage, driving the buffer mechanism (2) to descend or ascend, adjusting the vertical height of the landing gear, and performing a secondary adjustment on the parking attitude of the aircraft.

9. The landing gear landing attitude adjustment method according to claim 8, characterized in that: When landing, the lower end of the slide (3) is first subjected to gravity, causing the slide (3) to rotate around an axis hinged to the buffer mechanism (2), and the pneumatic actuator (7) is compressed until the slide (3) is completely grounded.

10. The landing gear landing attitude adjustment method according to claim 9, characterized in that: If the ground contacted by the skid (3) has a slope after the landing gear stops, the skid (3) will be driven to continue to rotate adaptively, causing the pneumatic actuator (7) to be further compressed until the skid (3) is completely in contact with the slope surface.

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