A self-deploying multi-stage telescopic variable damping mechanism
By using a self-deploying multi-stage telescopic variable damping mechanism, the problem of non-reusable launch vehicle buffer structures is solved. It achieves a multi-stage buffering effect with large size, bidirectional variable damping, and unidirectional pressure limiting, adapting to the refined design of multi-stage buffering performance for wide-range landing of medium and large launch vehicles, and improving buffering performance and load-bearing capacity.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- BEIJING INST OF ASTRONAUTICAL SYST ENG
- Filing Date
- 2024-10-22
- Publication Date
- 2026-05-26
AI Technical Summary
The existing vertical recovery buffer structure design of launch vehicles is not reusable and lacks a large-size, bidirectional variable damping and unidirectional pressure limiting multi-stage telescopic variable damping mechanism, which cannot meet the wide-area landing buffer requirements of medium and large launch vehicles.
A self-deploying multi-stage telescopic variable damping mechanism was designed, including a large end lug, a damping rod, a damping cylinder, an outer cylinder, a first-stage damping assembly, a second-stage damping assembly, a small end lug, and an oil tank. It adopts a multi-stage damping assembly and a unidirectional pressure limiting assembly to achieve a large-size, bidirectional variable damping and unidirectional pressure limiting buffering effect.
It has achieved a refined design of multi-stage buffer performance for medium and large launch vehicles under wide-range landing conditions, and adapted to the differentiated damping coefficient design for different stages of the flight, thereby improving buffer performance and load-bearing capacity.
Smart Images
Figure CN119262346B_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of reusable launch vehicle technology, specifically relating to a damping mechanism for a launch vehicle landing mechanism. Background Technology
[0002] As a crucial landing mechanism for the vertical recovery of launch vehicles, its buffer structure and performance directly affect the success or failure of the vertical recovery mission. Currently, vertical recovery of launch vehicles generally adopts a recovery scheme with a folding-leg landing buffer mechanism. The buffer structure design of this scheme mostly adopts metal crushing type such as aluminum honeycomb, and the buffer structure is integrated into the last section of the multi-stage landing mechanism. This type of buffer structure is not reusable. Some landing mechanisms use hydraulic buffer mechanisms, which are also integrated into the last section of the multi-stage landing mechanism or used as a separate support rod. Their size is relatively small and they do not have two-stage variable damping buffer capability. Summary of the Invention
[0003] The technical problem solved by this application is to overcome the shortcomings of the prior art and provide a large-size, bidirectional variable damping, unidirectional pressure-limiting multi-stage telescopic variable damping mechanism for the recovery of launch vehicle net systems. This mechanism can solve problems such as being applicable to the wide-range landing buffer conditions of medium and large launch vehicles, fine design of multi-stage buffer performance, and unidirectional pressure-limiting to improve buffer performance.
[0004] The technical solution provided in this application is as follows:
[0005] A self-deploying multi-stage telescopic variable damping mechanism includes a large-end support, a damping rod, a damping cylinder, an outer cylinder, a primary damping assembly, a secondary damping assembly, a small-end support, and an oil tank. The large-end support has an internal cavity. One end of the outer cylinder is connected to the large-end support, and the interior of the outer cylinder communicates with the internal cavity of the large-end support. The damping cylinder is slidably connected to the interior of the outer cylinder. The secondary damping assembly is connected to the outer wall of the damping cylinder near the large-end support. The damping rod is slidably connected to the inside of the damping cylinder, and the secondary damping assembly is connected to the end of the damping rod near the large-end support. The end of the damping rod away from the large-end support is connected to the small-end support. Sealing assemblies are provided between the end of the outer cylinder away from the large-end support and the damping cylinder, and between the end of the damping cylinder away from the large-end support and the damping rod. The oil tank communicates with the internal cavity of the large-end support. At least one of the small-end support and the large-end support is connected to the component requiring buffering.
[0006] A spring seat and a first spring are provided in the internal cavity of the large end support. The left end of the spring seat is directly opposite the end of the damping cylinder. One end of the first spring is in contact with the inside of the spring seat, and the other end is in contact with the inner wall surface of the internal cavity of the large end support away from the small end support.
[0007] The primary damping assembly includes a primary screw plug and multiple primary damping holes disposed on the primary screw plug. The primary screw plug is screwed and fixed to the end of the damping rod near the large end lug. The primary screw plug is cylindrical, and the outer diameter of the primary screw plug matches the damping cylinder. The primary damping holes connect the two sides of the primary screw plug along its own axial direction.
[0008] The secondary damping assembly includes a secondary screw plug and multiple secondary damping holes formed on the secondary screw plug. The secondary screw plug is threaded to the end of the outer wall of the damping cylinder near the large end lug. The outer diameter of the secondary screw plug matches the inner wall of the outer cylinder. The secondary damping holes connect the two sides of the secondary screw plug along its own axis.
[0009] The oil tank is connected to the large end support via an oil tank base. A one-way pressure limiting component is connected to the outlet of the oil tank to dampen the flow of oil from the internal cavity of the large end support into the oil tank. An oil tank piston is installed inside the oil tank. The space between the oil tank piston and the one-way pressure limiting component is the oil storage space. When oil in the oil tank flows into the internal cavity of the large end support through the one-way pressure limiting component, the oil tank piston moves towards the one-way pressure limiting component within the oil tank, and moves away from the one-way pressure limiting component.
[0010] The unidirectional pressure limiting assembly includes a spring sleeve, a pressure limiting spring, a pressure limiting element, a steel ball, and a pressure limiting piston. The fuel tank base is provided with a transverse connecting through hole and a longitudinal connecting through hole. The transverse connecting through hole is parallel to the length direction of the fuel tank, with one end communicating with the inner cavity of the fuel tank and the other end communicating with the inner cavity of the large end support through the longitudinal connecting through hole. The end of the transverse connecting through hole away from the longitudinal connecting through hole is a connecting hole, and the diameter of the connecting hole is larger than the diameter of the transverse connecting through hole. The fuel tank outlet is installed in the connecting hole, and the spring sleeve is installed at the fuel tank outlet. Inside the port, the pressure-limiting piston is fixedly connected to the transverse connecting through hole. The pressure-limiting component is located in the connecting hole and between the outlet of the oil tank and the pressure-limiting piston. The pressure-limiting spring is located in the spring sleeve and is used to push the pressure-limiting component. The steel ball is located in the pressure-limiting piston. Oil is supplied between the steel ball and the pressure-limiting piston. The diameter of the steel ball is larger than the inner diameter of the pressure-limiting component facing the steel ball. The pressure-limiting component is provided with a pressure-limiting damping hole so that after the steel ball blocks the end of the pressure-limiting component, the oil can enter the spring sleeve through the pressure-limiting damping hole. The end of the spring sleeve away from the pressure-limiting component is a through hole.
[0011] The inner wall of the pressure-limiting piston has multiple flow grooves circumferentially formed.
[0012] The end of the inner wall of the pressure-limiting piston away from the first flange is connected to a limiting part, and the steel ball is located on the side of the limiting part facing the pressure-limiting component.
[0013] The pressure limiting component is a cylindrical structure. It is inserted into the pressure limiting piston and is slidably connected to the pressure limiting piston along the axis of the pressure limiting piston. Multiple pressure relief grooves are provided on the outer wall surface of the pressure limiting component in the circumferential direction. The pressure relief grooves are distributed along the radial direction of the pressure limiting component. The pressure limiting damping hole extends from the inner wall surface of the pressure limiting component to the outer wall surface, and one end of the pressure limiting damping hole is connected to the pressure relief groove.
[0014] The pressure-limiting piston has a first flange on the outside of the end away from the longitudinal connecting through hole, and a stepped surface is formed between the connecting hole and the transverse connecting through hole. The end of the first flange is in contact with the stepped surface. The pressure-limiting component is connected to a second flange at the end away from the steel ball. The second flange is located on the side of the first flange away from the steel ball, and the outer diameter of the second flange is smaller than the inner diameter of the connecting hole.
[0015] In summary, this application includes at least the following beneficial technical effects:
[0016] (1) It is applicable to the wide-range landing buffer conditions of medium and large launch vehicles, and can be used for landing conditions such as large attitude deviation and large landing speed.
[0017] (2) The multi-level buffer performance adopted in this invention can be finely matched and designed. Different damping coefficients can be designed for different stroke stages to meet higher requirements for buffer performance.
[0018] (3) The present invention adopts a unidirectional pressure limiting structure, which improves the buffering performance and also improves the load-bearing capacity of the mechanism itself. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the overall structure of this patent;
[0020] Figure 2 for Figure 1 A sectional view;
[0021] Figure 3 for Figure 2 A magnified view of a portion of the image. Detailed Implementation
[0022] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments disclosed in the present invention will be described in further detail below with reference to the accompanying drawings.
[0023] This application discloses a self-deploying multi-stage telescopic variable damping mechanism, such as... Figure 1 and Figure 2 As shown, it includes a large end support 1, a spring seat 2, a damping rod 3-1, a damping cylinder 4-1, a primary damping assembly 3, a secondary damping assembly 4, an outer cylinder 5, a small end support 6, an oil tank piston 7, an oil tank 8, a one-way pressure limiting assembly 9, and an oil tank base 10.
[0024] The large end support 1 has an internal cavity. The large end support 1 is fixed to one end of the outer cylinder 5 by a screw connection. The internal space of the outer cylinder 5 communicates with the internal cavity of the large end support 1. The damping cylinder 4-1 is slidably connected to the inside of the outer cylinder 5. The secondary damping assembly 4 is connected to the end of the outer wall of the damping cylinder 4-1 near the large end support 1. A sealing assembly is provided between the end of the outer cylinder 5 away from the large end support 1 and the damping cylinder 4-1. The damping rod 3-1 is slidably connected to the inside of the damping cylinder 4-1. The secondary damping assembly 4 is connected to the end of the damping rod 3-1 near the large end support 1. A sealing assembly is provided between the end of the damping cylinder 4-1 away from the large end support 1 and the damping rod 3-1. The end of the damping rod 3-1 away from the large end support 1 is connected to the small end support 6 by a screw connection. At least one of the small end support 6 and the large end support 1 is connected to the component requiring buffering. The spring seat 2 is embedded in the cavity inside the large end support 1. The left end of the spring seat 2 is directly opposite the end of the damping cylinder 4-1. A first spring is installed inside the spring seat 2. One end of the first spring contacts the inside of the spring seat 2, and the other end contacts the inner wall surface of the cavity inside the large end support 1 away from the small end support 6, so as to provide an initial pushing force for the extension of the damping cylinder 4-1 and have a certain active unfolding function. The spring seat 2 has a weight reduction hole. A locking fixture is provided between the left end of the outer cylinder 5 and the small end support 6 for initial locking of the damping structure of this patent. When the damping mechanism of this solution is connected and locked with other components of the landing mechanism, the locking fixture of the damping mechanism is opened to release the initial pushing force lock, so as to ensure that after the landing mechanism is unlocked, the initial pushing force of the damping mechanism can unfold the other components of the landing mechanism.
[0025] The oil tank base 10 is connected to the large end support 1 via a flange or bolts, and the oil tank 8 is connected to the oil tank base 10 by bolts. The one-way pressure limiting component 9 is connected to the outlet of the oil tank 8 and acts as a damper during the flow of oil from the internal cavity of the large end support 1 into the oil tank 8, thereby reducing the flow rate of the oil and achieving one-way pressure limiting. The oil tank piston 7 is embedded in the internal cavity of the oil tank 8, and the space between the oil tank piston 7 and the one-way pressure limiting component 9 is the oil storage space. When the oil in the oil tank 8 flows into the internal cavity of the large end support 1 through the one-way pressure limiting component 9, the oil tank piston 7 moves towards the one-way pressure limiting component 9 within the oil tank 8, and moves away from the one-way pressure limiting component 9 in the opposite direction.
[0026] The primary damping assembly 3 includes a primary screw plug 3-3 and multiple primary damping holes 3-2 disposed on the primary screw plug 3-3. The primary screw plug 3-3 is screwed and fixed to the end of the damping rod 3-1 near the large end lug 1. The primary screw plug 3-3 is cylindrical, and its outer diameter mates with the damping cylinder 4-1. The primary damping holes 3-2 connect the two sides of the primary screw plug 3-3 along its own axial direction. The secondary damping assembly 4 includes a secondary screw plug 4-3 and multiple secondary damping holes 4-2 disposed on the secondary screw plug 4-3. The secondary screw plug 4-3 is threaded to the end of the outer wall of the damping cylinder 4-1 near the large end lug 1. The outer diameter of the secondary screw plug 4-3 mates with the inner wall of the outer cylinder 5. The secondary damping holes 4-2 connect the two sides of the secondary screw plug 4-3 along its own axial direction.
[0027] like Figure 3 As shown, the one-way pressure limiting assembly 9 consists of a pressure limiting spring 9-1, a pressure limiting component 9-2, a pressure relief groove 9-2-1, a pressure limiting damping hole 9-2-2, a steel ball 9-3, a pressure limiting piston 9-4, a flow groove 9-4-1, and a spring sleeve 9-5.
[0028] The oil tank base 10 is provided with a transverse connecting through hole and a longitudinal connecting through hole. The transverse connecting through hole is parallel to the length direction of the oil tank 8, with one end communicating with the inner cavity of the oil tank 8 and the other end communicating with the inner cavity of the large end support 1 through the longitudinal connecting through hole. The end of the transverse connecting through hole away from the longitudinal connecting through hole is a connecting hole, the diameter of which is larger than the diameter of the transverse connecting through hole, and a stepped surface is formed between the connecting hole and the transverse connecting through hole. The pressure limiting piston 9-4 is cylindrical, and the outer cylindrical surface of the pressure limiting piston 9-4 mates with the cylindrical surface of the transverse connecting through hole. A first flange is provided on the outside of the end of the pressure limiting piston 9-4 away from the longitudinal connecting through hole. The end of the first flange contacts the stepped surface, and the pressure limiting piston 9-4 is fixedly connected to the oil tank base 10. Multiple flow grooves 9-4-1 are opened circumferentially on the inner wall surface of the pressure limiting piston 9-4. The flow grooves 9-4-1 penetrate the pressure limiting piston 9-4 along the axial direction of the pressure limiting piston 9-4. A limiting part is connected to the end of the inner wall surface of the pressure limiting piston 9-4 away from the first flange. The steel ball 9-3 is located inside the pressure limiting piston 9-4 and is located on the side of the limiting part facing the first flange. The limiting part is used to limit the steel ball 9-3. When the steel ball 9-3 moves to contact the limiting part, it cannot continue to move towards the longitudinal connecting through hole. The end of the oil tank 8 is inserted into the connecting hole of the oil tank base 10. The spring sleeve 9-5 is inserted into the end of the oil tank 8 that extends into the connecting hole. The outer side of the spring sleeve 9-5 near the pressure limiting piston 9-4 is provided with a protrusion. The outer diameter of the protrusion matches the inner wall of the connecting hole. The protrusion is located on the side of the oil tank 8 facing the pressure limiting piston 9-4. A through hole is provided in the middle of the other end of the spring sleeve 9-5. The pressure limiting component 9-2 is a cylindrical structure, inserted into the pressure limiting piston 9-4, and slidably connected to the pressure limiting piston 9-4 along the axial direction of the pressure limiting piston 9-4. The diameter of the steel ball 9-3 is larger than the inner diameter of the pressure limiting component 9-2, and the steel ball 9-3 is located between the limiting part and the pressure limiting component 9-2. Multiple pressure relief grooves 9-2-1 are provided circumferentially on the outer wall surface of the pressure limiting component 9-2, and the pressure relief grooves 9-2-1 are distributed along the radial direction of the pressure limiting component 9-2. Multiple pressure limiting damping holes 9-2-2 are opened in the pressure limiting component 9-2, which penetrate from the inner wall surface to the outer wall surface, and one end of the pressure limiting damping hole 9-2-2 is connected to the pressure relief groove 9-2-1. The cross-sectional area of a single flow groove 9-4-1 is larger than the hole area of a single pressure limiting damping hole 9-2-2, and the flow in the flow groove 9-4-1 does not generate damping force. The end of the pressure-limiting component 9-2 away from the steel ball 9-3 is connected to a second flange. The second flange is located on the side of the first flange away from the steel ball 9-3, and its outer diameter is smaller than the inner diameter of the connecting hole. The pressure-limiting spring 9-1 is installed inside the spring sleeve 9-5. One end of the pressure-limiting spring 9-1 contacts the pressure-limiting component 9-2, and the other end contacts the inner wall of the spring sleeve 9-5 away from the pressure-limiting component 9-2. Thus, the pressure-limiting component 9-2 is subjected to the elastic force of the pressure-limiting spring 9-1. The spring sleeve 9-5 is constrained and limited by the spring force after the pressure-limiting spring 9-1 is compressed and by the oil tank 8 after installation. The spring seat 2 provides installation space for the push spring and provides a push-pull guiding function.
[0029] The primary damping component 3 provides the damping characteristics and buffering function of the damping rod 3-1 in both the extension and retraction directions; its main working principle is as follows:
[0030] a. Due to the flow restriction of the primary damping orifice during the extension and retraction of the damping rod 3-1, a pressure difference is generated on both sides of the primary damping orifice, thereby generating damping force.
[0031] b. According to design requirements, several primary damping holes 3-2 on the primary screw plug 3-3 can be fitted with sealing screw plugs, thereby changing the flow damping area of the primary screw plug 3-3 and achieving the designed damping buffering effect.
[0032] The secondary damping component 4 provides the damping characteristics and buffering function of the damping cylinder 4-1 in both the extension and retraction directions; its main working principle is as follows:
[0033] a. Due to the flow restriction of the secondary damping orifice during the expansion and contraction of the damping cylinder 4-1, a pressure difference is generated on both sides of the secondary damping orifice, thereby generating damping force;
[0034] b. According to design requirements, several secondary damping holes 4-2 on the secondary screw plug 4-3 can be sealed with plugs, thereby changing the flow damping area of the secondary screw plug 4-3 and achieving the designed damping buffering effect.
[0035] The unidirectional pressure limiting component 9 provides different damping characteristics and buffering effects in both expansion and contraction directions. Its main working principle is as follows:
[0036] a. When the damping rod 3-1 and / or the damping cylinder 4-1 are extended, the oil in the oil tank 8 flows into the large end support 6 through the one-way pressure limiting component 9. At this time, the steel ball 9-3 is separated from the end of the pressure limiting component 9-2 due to the action of hydraulic force. At this time, the oil flows into the cavity inside the large end support 1 and the cavity inside the outer cylinder 5 through the middle through hole of the spring sleeve 9-5, the middle channel of the pressure limiting component 9-2, and the pressure relief groove 9-2-1. At this time, the pressure limiting component 9-2 does not generate damping force. The damping force comes from the first-level damping component and the second-level damping component. The steel ball 9-3 stops moving after contacting the limiting part.
[0037] b. When the damping rod 3-1 and / or the damping cylinder 4-1 retract, the oil in the oil tank 8 flows into the one-way pressure limiting component 9 through the internal space of the large end support 1. At this time, the steel ball 9-3 is tightly attached to the end of the pressure limiting component 9-2 due to the action of hydraulic force. The oil flows into the oil tank through the pressure limiting damping hole 9-2-2 on the pressure limiting component 9-2. Due to the action of the pressure limiting damping hole 9-2-2, the pressure limiting component 9-2 generates a damping force. Therefore, the damping force at this time comes from the primary damping component, the secondary damping component, and the pressure limiting component. The combined action of components 9-2 and 9-3 constitutes a pressure limiting process. When the damping force generated by the oil flow is large, the steel ball 9-3 pushes the pressure limiting component 9-2 to compress the pressure limiting spring 9-1 by a certain stroke, causing the second flange to separate from the first flange. At this time, the oil flows through the pressure relief groove 9-2-1, between the first flange and the second flange, into the connecting hole, and then flows into the oil tank 8 through the through hole at the other end of the spring sleeve 9-5. This process is a pressure relief process. The pressure limiting process and the pressure relief process are carried out alternately.
[0038] The implementation principle of this patent is as follows:
[0039] This patent can be applied to the landing buffer mechanism of a launch vehicle's net system recovery system. The landing buffer mechanism includes a damping mechanism, an arresting mechanism, and a connection and unlocking mechanism. The large end lug 1 of the damping mechanism is hinged to the rocket body, and the small end lug 6 is hinged to the lug located in the middle of the arresting mechanism. The arresting mechanism has a lug connector at its root that is hinged to the rocket body. The connection and unlocking mechanism is used to unlock the connection between the arresting mechanism and the rocket body and is installed on the rocket body wall.
[0040] When the landing buffer mechanism is initially locked, the arresting mechanism is initially locked to the outer wall of the rocket body by the connection unlocking mechanism, with an angle of less than 5° with the central axis of the rocket body; the damping mechanism is in the fully retracted state.
[0041] When the landing buffer mechanism needs to deploy and capture the rocket body, the arresting mechanism is unlocked by the connection unlocking mechanism. The initial thrust of the damping mechanism pushes the arresting mechanism open to achieve rotational deployment. During the rotational deployment and capture process of the arresting mechanism, the damping mechanism performs the damping buffering function.
[0042] The contents not described in detail in this application specification are common knowledge to those skilled in the art.
[0043] The present application has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present application. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and implementation methods of the present application without departing from the spirit and scope of the present application, and all such modifications and improvements fall within the scope of the present application. The scope of protection of the present application is determined by the appended claims.
Claims
1. A self-expanding multi-stage telescopic variable damping mechanism, characterized in that: It includes a large-end lug (1), a damping rod (3-1), a damping cylinder (4-1), an outer cylinder (5), a primary damping component (3), a secondary damping component (4), a small-end lug (6) and an oil tank (8). The large-end lug (1) has an internal cavity. One end of the outer cylinder (5) is connected to the large-end lug (1), and the interior of the outer cylinder (5) is communicated with the internal cavity of the large-end lug (1). The damping cylinder (4-1) is slidably connected to the interior of the outer cylinder (5). The secondary damping component (4) is connected to one end of the outer wall surface of the damping cylinder (4-1) close to the large-end lug (1). The damping rod (3-1) is slidably connected to the inside of the damping cylinder (4-1). The secondary damping component (4) is connected to one end of the damping rod (3-1) close to the large-end lug (1). The end of the damping rod (3-1) far from the large-end lug (1) is connected to the small-end lug (6). Sealing components are provided between the end of the outer cylinder (5) far from the large-end lug (1) and the damping cylinder (4-1), and between one end of the damping cylinder (4-1) far from the large-end lug (1) and the damping rod (3-1). The oil tank (8) is communicated with the internal cavity of the large-end lug (1). At least one of the small-end lug (6) and the large-end lug (1) is connected to a component that needs buffering. The primary damping component (3) includes a primary plug (3-3) and a plurality of primary damping holes (3-2) provided on the primary plug (3-3). The primary plug (3-3) is screwed and fixed to the end of the damping rod (3-1) close to the large-end lug (1). The primary plug (3-3) is cylindrical, the outer diameter of the primary plug (3-3) is matched with the damping cylinder (4-1), and the primary damping holes (3-2) communicate the two sides of the primary plug (3-3) along its own axis. The secondary damping component (4) includes a secondary plug (4-3) and a plurality of secondary damping holes (4-2 provided on the secondary plug (4-3). The secondary plug (4-3) is threadedly connected to the end of the outer wall of the damping cylinder (4-1) close to the large-end lug (1). The outer diameter of the secondary plug (4-3) is matched with the inner wall of the outer cylinder (5), and the secondary damping holes (4-2) communicate the two sides of the secondary plug (4-3) along its own axis. The oil tank (8) is connected to the large-end lug (1) through an oil tank base (10). A one-way pressure limiting component (9) is connected to the outlet position of the oil tank (8) to play a damping role when the fluid in the internal cavity of the large-end lug (1) flows into the oil tank (8). An oil tank piston (7) is arranged in the oil tank (8). The space between the oil tank piston (7) and the one-way pressure limiting component (9) is the storage space of the oil fluid. When the oil in the oil tank (8) flows into the internal cavity of the large-end lug (1) through the one-way pressure limiting component (9), the oil tank piston (7) moves in the oil tank (8) in the direction close to the one-way pressure limiting component (9), and vice versa in the direction away from the one-way pressure limiting component (9). A locking tooling is provided between the left end of the outer cylinder (5) and the small-end lug (6) for locking the initial state of the damping structure.
2. The self - deploying multi - stage telescopic variable - damping mechanism according to claim 1, wherein: In the internal cavity of the large-end lug (1), a spring seat (2) and a first spring are provided. The left end of the spring seat (2) faces the end of the damping cylinder (4-1). One end of the first spring contacts the inside of the spring seat (2), and the other end contacts the inner wall surface of the internal cavity of the large-end lug (1) away from the small-end lug (6).
3. The self-expanding multi-stage telescopic variable damping mechanism according to claim 1, wherein: The one-way pressure-limiting component (9) includes a spring sleeve (9-5), a pressure-limiting spring (9-1), a pressure-limiting member (9-2), a steel ball (9-3), and a pressure-limiting piston (9-4). The fuel tank base (10) is provided with a transverse connection through-hole and a longitudinal connection through-hole. The transverse connection through-hole is parallel to the length direction of the fuel tank (8), and one end communicates with the inner cavity of the fuel tank (8), and the other end communicates with the internal cavity of the large-end lug (1) through the longitudinal connection through-hole. The end of the transverse connection through-hole away from the longitudinal connection through-hole is a connection hole, and the diameter of the connection hole is larger than that of the transverse connection through-hole. The outlet of the fuel tank (8) is installed in the connection hole. The spring sleeve (9-5) is installed in the outlet of the fuel tank (8). The pressure-limiting piston (9-4) is fixedly connected in the transverse connection through-hole. The pressure-limiting member (9-2) is located in the connection hole and between the outlet of the fuel tank (8) and the pressure-limiting piston (9-4). The pressure-limiting spring (9-1) is located in the spring sleeve (9-5) and is used to push the pressure-limiting member (9-2). The steel ball (9-3) is located in the pressure-limiting piston (9-4), and the space between the steel ball (9-3) and the pressure-limiting piston (9-4) is for fuel oil to pass through. The diameter of the steel ball (9-3) is larger than the inner diameter of the end of the pressure-limiting member (9-2) facing the steel ball. The pressure-limiting member (9-2) is provided with a pressure-limiting damping hole (9-2-2) so that after the steel ball (9-3) blocks the end of the pressure-limiting member (9-2), the oil can enter the spring sleeve (9-5) through the pressure-limiting damping hole (9-2-2). The end of the spring sleeve (9-5) away from the pressure-limiting member (9-2) is a through-hole.
4. The self - deploying multi - stage telescopic variable - damping mechanism according to claim 3, wherein: A plurality of flow grooves (9-4-1) are circumferentially formed on the inner wall surface of the pressure-limiting piston (9-4).
5. The self - deploying multi - stage telescopic variable damping mechanism according to claim 3, wherein: A limiting portion is connected to the end of the inner wall surface of the pressure-limiting piston (9-4) away from the first flange, and the steel ball (9-3) is located on the side of the limiting portion facing the pressure-limiting member (9-2).
6. The self - deploying multi - stage telescopic variable - damping mechanism according to claim 3, wherein: The pressure-limiting member (9-2) is of a cylindrical structure. The pressure-limiting member (9-2) is inserted into the pressure-limiting piston (9-4) and is slidably connected to the pressure-limiting piston (9-4) along the axis direction of the pressure-limiting piston (9-4). A plurality of pressure relief grooves (9-2-1) are circumferentially provided on the outer wall surface of the pressure-limiting member (9-2), and the pressure relief grooves (9-2-1) are distributed along the radial direction of the pressure-limiting member (9-2). The pressure-limiting damping hole (9-2-2) penetrates from the inner wall surface of the pressure-limiting member (9-2) to the outer wall surface, and one end of the pressure-limiting damping hole (9-2-2) communicates with the pressure relief groove (9-2-1).
7. The self-expanding multi-stage telescopic variable damping mechanism according to claim 3, characterized in that: A first flange is provided outside the end of the pressure-limiting piston (9-4) away from the longitudinal connection through-hole. A step surface is formed between the connection hole and the transverse connection through-hole, and the end of the first flange contacts the step surface; a second flange is connected to the end of the pressure-limiting member (9-2) away from the steel ball (9-3). The second flange is located on the side of the first flange背离钢球(9-3)的一侧, and the outer diameter of the second flange is smaller than the inner diameter of the connection hole.