A multi-stage pneumatic telescopic mechanism with repeatable locking and unlocking

Abstract

The present invention discloses a multi-stage pneumatic telescopic mechanism that can be repeatedly locked and unlocked. The use of the present invention can provide a good locking function for the multi-stage pneumatic telescopic mechanism, and can perform orderly unlocking to realize the folding function of the cylinder. The present invention includes a multi-stage cylinder, a lock in the cylinder, a seal, a support ring, and an air inlet nozzle, etc., which combines a thin-walled cylinder with a wedge lock, has a large load-bearing capacity and a fast response, and can be extended at high speed and remain locked under the action of high-pressure gas. In the locked state, the automatic unlocking function of the lock in the cylinder can be realized by passing a certain pressure gas from the unlocking air inlet nozzle. The present invention has high maintainability, easy replacement of vulnerable and consumable parts, and has the functions of repeatedly locking, bearing, unlocking and folding. It has high reliability and can be used for ground landing legs of reusable carriers or spacecraft with large load-bearing capacity requirements.

Description

Technical Field

[0001] The invention belongs to the mechanical field and relates to a multi-stage pneumatic telescopic mechanism. Background Art

[0002] Reusable technology is considered an important means to reduce space transportation costs and an effective way to improve rapid response space capabilities. At present, the United States, Europe, Russia, Japan, India and other countries have conducted extensive research on reusable launch vehicle technology. Among them, the most influential are the US SpaceX and Blue Origin, which have achieved the recovery and utilization of the rocket body through the ground landing of the first stage of the rocket.

[0003] The deployable outrigger landing method is widely used in the soft landing of carriers or landers. As the demand for heavy and economical carriers or landers becomes more urgent, the requirements for landing legs in terms of large load-bearing performance, reusability and reliability are getting higher and higher. However, traditional landing legs usually have the disadvantages of complex structure, inability to automatically unlock, limited load-bearing capacity and poor reusability. Summary of the invention

[0004] The technical problem to be solved by the present invention is: the present invention provides a multi-stage telescopic mechanism with repeated locking and unlocking functions, rapid deployment and locking, large load-bearing capacity and high reliability.

[0005] The technical solution adopted by the present invention is: a multi-stage pneumatic telescopic mechanism that can be repeatedly locked and unlocked, including a bottom end cover, a top end cover, a multi-stage cylinder, a lock inside the cylinder and an air inlet nozzle;

[0006] The multi-stage cylinder includes a plurality of cylinders with different diameters in a coaxial nested structure, wherein each stage of the cylinder slides axially in its adjacent outer cylinder;

[0007] The air inlet nozzle is divided into an unfolded air inlet nozzle and an unlocked air inlet nozzle. The unfolded air inlet nozzle is installed on the bottom end cover, and the unlocked air inlet nozzle is installed on the top end cover. The cylinder lock is installed between adjacent cylinders of the multi-stage cylinder, and is a wedge block locking component that automatically locks under elastic force.

[0008] When gas is introduced from the expansion air inlet nozzle, the multi-stage cylinder is extended under the action of air pressure and locked in place; when the multi-stage cylinder is in the locked state, gas is introduced from the unlocking air inlet nozzle, the lock inside the cylinder is automatically unlocked, and the multi-stage cylinder is retracted.

[0009] The inner lock of the cylinder includes a lock cylinder, a wedge block, a slider, a piston, a locking spring, a support ring and an unlocking ring; the lock cylinder is a stepped cylinder, the support ring is installed on the inner wall of the small end of the lock cylinder, and a wedge block groove is arranged on the inner wall of the large end of the lock cylinder; the unlocking ring and the piston are installed at the end of the cylinder, the locking spring and the slider are sleeved on the central cylinder of the unlocking ring, the central cylinder of the unlocking ring extends into the piston, and the flange structure at the end of the central cylinder of the unlocking ring limits the slider; a plurality of wedge block mounting holes are arranged along the circumferential direction at one end of the piston, the wedge block is installed in the wedge block mounting hole, the slider moves along the inner wall of the piston under the action of the locking spring, the piston is installed in the large end of the lock cylinder, the small end of the lock cylinder is connected to the end of the next-level cylinder, and the support ring slides along the outer wall of the next-level cylinder; under the push of the slider, the wedge block is inserted into the wedge block groove on the inner wall of the lock cylinder to achieve locking.

[0010] The locking spring is kept in contact with the slider in a compressed state.

[0011] The wedge blocks are arc-shaped blocks with a trapezoidal cross section and are evenly arranged along the circumference of the piston.

[0012] The cylinder lock also includes a sealing member, which is installed on the inner wall of the small end of the lock cylinder to prevent air leakage.

[0013] A sealing ring is arranged between the unlocking ring and the inner wall of the cylinder.

[0014] Expand the air inlet nozzle to let in gas, pushing the piston to move along the cylinder. After the end of the piston enters the lock cylinder, the locking spring in a compressed state pushes the slider to move. The slider pushes the wedge block out of the wedge block mounting hole and snaps into the wedge block slot of the lock cylinder to achieve locking.

[0015] Unlock the air inlet nozzle to let in gas, push the slider to release the wedge block, release the lock, and allow the piston to move in the cylinder to achieve the contraction of the multi-stage cylinder.

[0016] The number of wedges is 6 or 12.

[0017] The cylinder barrel is made of stainless steel.

[0018] The beneficial effects of the present invention compared with the prior art are:

[0019] (1) The present invention uses pneumatic pressure as a driving source, has a high deployment speed, and can realize orderly step-by-step deployment or folding functions;

[0020] (2) The present invention adopts a wedge block as the lock core structure of the cylinder lock, which has the characteristics of compact layout and large load-bearing capacity; the present invention can provide a good locking function for the multi-stage pneumatic telescopic mechanism, and can perform orderly unlocking to realize the retracting function of the cylinder.

[0021] (3) The present invention has a simple structure, is easy to disassemble and assemble, has good maintainability, can be reused many times, has a large load-bearing capacity, a long stroke, and can be quickly deployed, and is used as a ground landing leg for a reusable carrier or spacecraft. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a cross-sectional view of the structure of the unfolded and locked state of the multi-stage pneumatic telescopic mechanism of the present invention that can be repeatedly locked and unlocked;

[0023] Figure 2 It is a cross-sectional view of the structure of the retracted state of the multi-stage pneumatic telescopic mechanism that can be repeatedly locked and unlocked according to the present invention;

[0024] Figure 3 It is a structural schematic diagram of the lock cylinder of the present invention;

[0025] Figure 4 It is a schematic diagram of the structure of the wedge block of the present invention;

[0026] Figure 5 It is a schematic structural diagram of the piston of the present invention.

[0027] Description of the numbers in the figure:

[0028] 1 is the bottom end cover, 2 is the first-stage cylinder, 3 is the first-stage cylinder inner lock, 4 is the second-stage cylinder, 5 is the second-stage cylinder inner lock, 6 is the third-stage cylinder, 7 is the third-stage cylinder inner lock, 8 is the fourth-stage cylinder, 9 is the top end cover, 10 is the support ring, 11 is the sealing ring, 12 is the lock cylinder, 13 is the wedge block, 14 is the slider, 15 is the piston, 16 is the locking spring, and 17 is the unlocking ring. DETAILED DESCRIPTION

[0029] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0030] like Figure 1 , Figure 2 As shown, the multi-stage pneumatic telescopic mechanism of the present invention that can be repeatedly locked and unlocked includes a bottom end cover 1, a top end cover 9, a multi-stage cylinder, a cylinder inner lock and an air inlet nozzle. The cylinder inner lock includes a lock cylinder 12, a wedge block 13, a slider 14, a piston 15, a locking spring 16, a seal 11, a support ring 10, and an unlocking ring 17.

[0031] The multi-stage cylinder is a coaxial cylinder structure formed by a series of thin-walled cylinders with different diameters nested with each other. Each stage of the cylinder can slide axially in its adjacent outer cylinder.

[0032] The air inlet nozzle is divided into an expansion air inlet nozzle and an unlocking air inlet nozzle, which are respectively installed on the end covers of the multi-stage pneumatic telescopic mechanism. High-pressure gas is introduced from the expansion air inlet nozzle to generate an outward thrust on the unlocking ring 17 at the bottom of each cylinder, and the unlocking ring 17 pushes the cylinder and the lock inside the cylinder to extend outward and lock in place; when the multi-stage pneumatic telescopic mechanism is in the locked state, a certain pressure gas is introduced from the unlocking air inlet nozzle, and the gas thrust overcomes the elastic force of the locking spring 16 to make the slider 14 leave the locked position, which can realize the automatic unlocking function of the lock inside the cylinder.

[0033] The in-cylinder lock is installed between adjacent cylinders of the multi-stage cylinder. It is a wedge block locking assembly that automatically locks under elastic force. The wedge block 13 is nested between the lock cylinder 12 and the piston 15 of the in-cylinder lock and is evenly installed along the circumference, serving as a lock core to realize the in-place locking function of the multi-stage cylinder.

[0034] The cylinder lock includes a lock cylinder 12, a wedge block 13, a slider 14, a piston 15, a locking spring 16, a support ring 10, an unlocking ring 17, and a seal 11; Figure 3 As shown, the lock cylinder 12 is a stepped cylinder, the support ring 10 and the seal 11 are installed on the inner wall of the small end of the lock cylinder 12, and the inner wall of the large end of the lock cylinder 12 is provided with a wedge block slot; the unlocking ring 17 and the piston 15 are installed at the end of the cylinder, the locking spring 16 and the slider 14 are sleeved on the central cylinder of the unlocking ring 17, and the central cylinder of the unlocking ring 17 extends into the piston 15; Figure 5 As shown, a plurality of wedge block mounting holes are arranged along the circumference at one end of the piston 15, and the wedge block 13 is installed in the wedge block mounting hole. The slider 14 moves along the inner wall of the piston 15 under the action of the locking spring 16. The piston 15 is installed in the large end of the lock cylinder 12, and the small end of the lock cylinder 12 is connected to the end of the next cylinder. The support ring 10 slides along the outer wall of the next cylinder. Under the push of the slider 14, the wedge block 13 is inserted into the wedge block slot on the inner wall of the lock cylinder 12 to achieve locking. Figure 4 As shown, the wedge blocks 13 are arc-shaped blocks with a trapezoidal cross section and are evenly arranged along the circumference of the piston 15. A sealing ring is arranged between the unlocking ring 17 and the inner wall of the cylinder.

[0035] The air inlet nozzle is unfolded to let in gas, pushing the piston 15 to move along the cylinder. After the end of the piston 15 enters the lock cylinder 12, the locking spring 16 in a compressed state pushes the slider 14 to move. The slider 14 pushes the wedge block 13 out of the wedge block mounting hole and snaps it into the wedge block slot of the lock cylinder 12 to achieve locking.

[0036] Unlock the air inlet nozzle to let in gas, push the slider 14 to release the wedge block 13, and release the lock, so that the piston 15 moves in the cylinder, realizing the contraction of the multi-stage cylinder.

[0037] The seal 11 and the support ring 10 are installed at the end of the lock cylinder 12 to ensure the airtightness requirement of the multi-stage pneumatic telescopic mechanism during the telescopic process, and to radially support the multi-stage cylinder to achieve the coaxiality requirement of the multi-stage cylinder.

[0038] The multi-stage pneumatic telescopic mechanism can extend the multi-stage cylinder barrel by introducing gas from the expansion air inlet nozzle to realize the step-by-step expansion function of the multi-stage pneumatic telescopic mechanism; the lock inside the cylinder can be unlocked by introducing gas from the unlocking air inlet nozzle, and the step-by-step unlocking function of the multi-stage pneumatic telescopic mechanism can be realized with the cooperation of the unlocking ring.

[0039] The number and length of the multi-stage cylinder can be adaptively adjusted according to usage requirements.

[0040] The number of wedge blocks locked in the cylinder can be reasonably determined based on the layout space of the multi-stage cylinder and the load-bearing requirements of the multi-stage pneumatic telescopic mechanism.

[0041] Example:

[0042] The embodiment of the present invention takes a four-stage pneumatic telescopic mechanism as an example, and its unfolded and locked state structure is as follows: Figure 1 As shown, the bottom end cover 1 is provided with an expansion air inlet, the bottom end cover 1 is fixedly connected to the first-stage cylinder 2, the first-stage cylinder inner lock 3 is respectively connected to the first-stage cylinder 2 and the second-stage cylinder 4, the second-stage cylinder inner lock 5 is respectively connected to the second-stage cylinder 4 and the third-stage cylinder 6, the third-stage cylinder inner lock 7 is respectively connected to the third-stage cylinder 6 and the fourth-stage cylinder 8, the top end cover 9 is installed at the end of the fourth-stage cylinder 8, and is provided with an unlocking air inlet, the support ring 10 and the sealing ring 11 are used in conjunction with the cylinder inner lock and form a sliding motion pair with the inner wall or outer wall of the cylinder. The four-stage pneumatic telescopic mechanism can realize a reliable expansion and locking function by ventilating the expansion air inlet of the bottom end cover 1, and can realize an unlocking function by ventilating the unlocking air inlet of the top end cover 9.

[0043] The cylinder lock of the embodiment of the present invention is installed between two adjacent cylinders of the multi-stage cylinder, the wedge block 13 is constrained in the locking hole of the piston 15, the lock cylinder 12 and the piston 15 are connected as a whole, the locking spring 16 is sleeved on the outer cylindrical surface of the unlocking ring 17, and is kept in contact with the slider 14 in a compressed state. When the multi-stage pneumatic telescopic mechanism is deployed in place, the cylinder lock is under the elastic force of the locking spring 16, and the slider 14 automatically pushes the wedge block 13 radially out and nests between the lock cylinder 12 and the piston 15 to achieve the locking function.

[0044] Ventilate from the unlocking air inlet of the top end cover 9, push the slider 14, unlock the wedge block 13, the wedge block 13 moves inward to achieve unlocking, push the piston 15 to slide along the inner wall of the next cylinder, and achieve the contraction of each cylinder.

[0045] In the cylinder lock of the embodiment of the present invention, the number and size of the wedge blocks 13 are limited by the layout space and load-bearing requirements of the multi-stage cylinder. The principle is that the wedge blocks 13 are evenly spaced along the circumference of the piston 15, and the preferred number is 6 or 12.

[0046] The multi-stage cylinder barrel of the embodiment of the present invention can be made of thin-walled stainless steel material. If the structural size allows, thick-walled lightweight non-metallic material is also a better choice.

[0047] The wall thickness, diameter, etc. of the multi-stage cylinder in the embodiment of the present invention should take into account the load-bearing strength and stability performance of the multi-stage pneumatic telescopic mechanism. The number of multi-stage cylinders can be adjusted according to the folded height and unfolded length requirements of the multi-stage pneumatic telescopic mechanism, but the preferred solution should be that the fewer the number of multi-stage cylinders, the better.

[0048] Although the present invention is disclosed as above with preferred embodiments, it is not intended to limit the claims. Any changes, modifications, equivalent substitutions and improvements made by any person skilled in the art without departing from the spirit and scope of the present invention shall be included in the protection scope of the present invention.

[0049] Parts of the present invention that are not described in detail belong to the well-known technologies of those skilled in the art.

Claims

1. A multi-stage pneumatic telescopic mechanism that can be repeatedly locked and unlocked, characterized in that: It comprises a bottom end cover (1), a top end cover (9), a multi-stage cylinder, an inner cylinder lock and an air inlet nozzle; The multi-stage cylinder includes a plurality of cylinders with different diameters in a coaxial nested structure, wherein each stage of the cylinder slides axially in its adjacent outer cylinder; The air inlet nozzle is divided into an unfolded air inlet nozzle and an unlocked air inlet nozzle, the unfolded air inlet nozzle is mounted on the bottom end cover (1), and the unlocked air inlet nozzle is mounted on the top end cover (9); the cylinder lock is mounted between adjacent cylinder barrels of the multi-stage cylinder barrel, and is a wedge block locking component that automatically locks under elastic force; Gas is introduced from the deployment air inlet nozzle, and the multi-stage cylinder is extended and locked in place under the action of gas pressure; When the multi-stage cylinder is in the locked state, gas is introduced from the unlocking air inlet nozzle, the lock inside the cylinder is automatically unlocked, and the multi-stage cylinder shrinks; The cylinder lock comprises a lock cylinder (12), a wedge block (13), a slider (14), a piston (15), a locking spring (16), a support ring (10), and an unlocking ring (17); the lock cylinder (12) is a stepped cylinder, the support ring (10) is mounted on the inner wall of the small end of the lock cylinder (12), and a wedge block slot is arranged on the inner wall of the large end of the lock cylinder (12); the unlocking ring (17) and the piston (15) are mounted on the end of the cylinder, the locking spring (16) and the slider (14) are sleeved on the central cylinder of the unlocking ring (17), the central cylinder of the unlocking ring (17) extends into the piston (15), and the unlocking ring (17) ) is used to limit the slider (14); a plurality of wedge block mounting holes are arranged along the circumferential direction at one end of the piston (15), the wedge block (13) is mounted in the wedge block mounting hole, the slider (14) moves along the inner wall of the piston (15) under the action of the locking spring (16), the piston (15) is mounted in the large end of the lock cylinder (12), the small end of the lock cylinder (12) is connected to the end of the next-stage cylinder, and the support ring (10) slides along the outer wall of the next-stage cylinder; under the push of the slider (14), the wedge block (13) is clamped into the wedge block clamping groove on the inner wall of the lock cylinder (12) to achieve locking; The wedge blocks (13) are arc-shaped blocks and are evenly arranged along the circumference of the piston (15); The locking spring (16) remains in contact with the slider (14) in a compressed state.

2. A multi-stage pneumatic telescopic mechanism capable of repeated locking and unlocking according to claim 1, characterized in that: The cylinder lock further comprises a sealing member (11), which is mounted on the inner wall of the small end of the lock cylinder (12) to prevent air leakage.

3. A multi-stage pneumatic telescopic mechanism capable of repeated locking and unlocking according to claim 2, characterized in that: A sealing ring is arranged between the unlocking ring (17) and the inner wall of the cylinder.

4. A multi-stage pneumatic telescopic mechanism capable of repeated locking and unlocking according to claim 3, characterized in that: The air inlet nozzle is unfolded to allow gas to flow in, pushing the piston (15) to move along the cylinder. After the end of the piston (15) enters the lock cylinder (12), the locking spring (16) in a compressed state pushes the slider (14) to move, and the slider (14) pushes the wedge block (13) out of the wedge block mounting hole and snaps into the wedge block snap groove of the lock cylinder (12), thereby achieving locking.

5. A multi-stage pneumatic telescopic mechanism capable of repeated locking and unlocking according to claim 4, characterized in that: The air inlet nozzle is unlocked to allow gas to enter, pushing the slider (14) to release the wedge block (13), thereby releasing the lock and allowing the piston (15) to move in the cylinder, thereby achieving the contraction of the multi-stage cylinder.

6. The multi-stage pneumatic telescopic mechanism capable of repeated locking and unlocking according to claim 1, characterized in that: The number of wedge blocks (13) is 6 or 12.

7. The multi-stage pneumatic telescopic mechanism capable of repeated locking and unlocking according to claim 1, characterized in that: The cylinder barrel is made of stainless steel.

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