A gas cylinder usable for launch vehicle stage separation

Abstract

A cylinder for carrying rocket interstage separation, comprising: a lower end cover, a lower end flange, a cylinder barrel, an upper end flange, an upper end cover, a piston head, a piston rod, a double seal ring, a double support ring, a charging port and an exhaust damping hole. The piston head and the piston rod are connected by threads to form an integral cylinder internal structure and are located inside the cylinder barrel; the lower end cover is installed on one end of the cylinder barrel where the piston head is arranged through the lower end flange, and a cavity formed between the lower end cover and the piston head is a rodless cavity; the double seal ring and the double support ring are installed between the piston head and the cylinder barrel; the upper end cover is installed on the other end of the cylinder barrel through the upper end flange, the piston rod passes out of the center hole of the upper end cover, and a rod cavity is formed between the piston rod and the cylinder barrel; the double seal ring and the double support ring are also arranged between the upper end cover and the piston rod; the lower end cover and the upper end cover are both provided with the charging port and the exhaust damping hole for charging and exhausting the rodless cavity and the rod cavity, respectively. The cylinder has high reliability, large thrust and strong sealing performance.

Description

Technical Field

[0001] This utility model relates to a cylinder that can be used for interstage separation of launch vehicles, belonging to the field of interstage separation technology for launch vehicles. Background Technology

[0002] As reusability becomes an inevitable direction for the development of launch vehicles, non-pyrotechnic connection and separation technologies, represented by aerodynamic separation technology, are gradually replacing traditional pyrotechnic connection and separation technologies and becoming an important way for the next generation of rockets to achieve reusability.

[0003] As the most critical component in the aerodynamic separation of launch vehicle stages, the cylinder directly affects the success or failure of interstage separation, thus determining the success or failure of satellite launch missions. While cylinders are widely used in industry, their application in industrial settings presents several limitations compared to space launch missions. These limitations include: ① High-speed, high-load separation, requiring rapid separation of hundreds-ton-class components within 1 second or even less; ② High-reliability, high-sealing separation, where leaks in spaceflight missions reduce cylinder actuation capacity, failing to meet launch vehicle separation thrust requirements and leading to mission failure; ③ While leaks in industrial products can be resolved through repairs, in space launch missions, repairs can lead to mission schedule adjustments or cancellations, causing significant disruptions. Therefore, a comprehensive consideration of the cylinder's axial and lateral load-bearing capacities is necessary. Utility Model Content

[0004] The technical problem solved by this utility model is to overcome the shortcomings of the prior art and propose a cylinder that can be used for interstage separation of launch vehicles. It has the characteristics of high reliability, large thrust and strong sealing, and can be applied to the aerodynamic separation between launch vehicle stages.

[0005] The technical solution adopted in this utility model is as follows:

[0006] A cylinder that can be used for interstage separation of a launch vehicle includes: a lower end cover, a lower end flange, a cylinder barrel, an upper end flange, an upper end cover, a piston head, a piston rod, a double-seal ring, a double-support ring, an air inlet, and an exhaust damping hole;

[0007] The piston head and piston rod are connected by threads to form an integral part of the cylinder internal structure and are located inside the cylinder barrel; the lower end cover is installed on the cylinder barrel at the end where the piston head is located through the lower end flange, and the cavity formed between the lower end cover and the piston head is a rodless cavity; double sealing rings and double support rings are installed between the piston head and the cylinder barrel.

[0008] The upper end cover is installed on the other end of the cylinder via the upper end flange. The piston rod passes through the center hole of the upper end cover, and the cavity formed between the piston rod and the cylinder is a rod cavity. Double sealing rings and double support rings are also provided between the upper end cover and the piston rod.

[0009] Both the lower and upper end caps are equipped with an air inlet and an exhaust damping hole, which are used to inflate and exhaust the rodless and rod-type chambers, respectively.

[0010] Furthermore, in the dual-seal design, the first seal is an inner seal ring, which has a bidirectional sealing function, and the second seal is an outer seal ring, which also has a bidirectional sealing function.

[0011] Furthermore, the two sealing rings of the double sealing ring and the two support rings of the double support ring are alternately arranged.

[0012] Furthermore, the rodless cavity and the rod cavity are two independent, non-communicating sealed cavities.

[0013] Furthermore, both the lower and upper end caps are equipped with temperature and pressure measuring ports, which are used to connect external temperature and pressure measuring devices to measure the temperature and pressure in the rodless and rod-type chambers, respectively.

[0014] Furthermore, it also includes four eye bolts, a process plug, and a fuse;

[0015] The process plug is installed on the piston rod end, one eye bolt is installed on the process plug, and three eye bolts are installed on the front end cap. The three eye bolts installed on the front end cap and the one eye bolt installed on the process plug are connected by a fuse. The three eye bolts installed on the front end cap are used for cylinder lifting.

[0016] Furthermore, by adjusting the diameter of the exhaust damping hole in the upper end cover, the cylinder piston can discharge the air volume in the rod chamber at different speeds during operation, thereby enabling the piston to decelerate according to the specified requirements.

[0017] Furthermore, the exhaust damping orifice is equipped with a plug, which prevents gas from escaping when the plug is closed.

[0018] Furthermore, the rodless chamber of the cylinder is pre-pressurized so that the piston always maintains a certain preload force with the separated body during the flight of the launch vehicle.

[0019] The advantages of this utility model over the prior art are as follows:

[0020] (1) This utility model adopts a double-seal ring design for sealing, which takes into account both the requirements for sealing performance and low friction, and is applicable to the field of aerospace technology. Simultaneously, the double-support ring design ensures the reliability requirements of the double-seal ring. These two designs can meet the sealing requirements for aerodynamic separation between launch vehicle stages. The double-seal ring design can separately prevent gas communication between the rodless chamber and the rod chamber, and between the rod chamber and the external gas.

[0021] (2) Since the present invention adopts a double support method between the two seals, it can prevent the piston rod from deforming under the action of lateral force during operation, thereby ensuring its sealing performance and improving its lateral load-bearing capacity.

[0022] (3) This utility model integrates the air inlet and damping exhaust port on the upper and lower end caps, making the cylinder structure more compact and avoiding the risk of seal damage caused by designing the opening on the cylinder barrel. The pressure and temperature measurement interfaces are integrated on the upper and lower end caps, simplifying the launch vehicle measurement system interface, while allowing for the measurement of the temperature and pressure of the gas inside the cylinder.

[0023] (4) The present invention features an exhaust damping hole designed on the upper end cover. The exhaust damping hole allows the gas in the rod chamber (the chamber with the piston rod) of the cylinder to communicate with the external ambient gas. By designing the diameter of the damping hole, the cylinder piston can discharge the gas in the rod chamber at different speeds during operation, thereby enabling the piston to decelerate according to the specified requirements, making the launch vehicle safer during interstage separation.

[0024] (5) The present invention has a pre-pressurized cavity and a cross-shaped exhaust damping hole designed in the rear end cover, which makes the cylinder structure design more compact. In addition to meeting the functions of inflation and exhaust, it can also realize the pre-pressurization of the rodless cavity of the cylinder. In this way, the piston can always be in contact with the separated body with a certain pre-tightening force during the flight of the launch vehicle, and realize the rapid separation of the launch vehicle.

[0025] (6) This utility model takes into account the problem of fixing moving parts during product transportation, lifting, and flight conditions. Through the structural design of process lifting eye screws, process plugs, and fuses, the lifting function of the cylinder and the fixing function of the cylinder piston can be met, thus satisfying the requirements of the cylinder during transportation. After the transportation and lifting requirements are met, the process plugs and lifting eye screws can be removed during the final assembly stage of the launch vehicle to meet the requirements for use in the final product. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the overall structure of the cylinder of this utility model;

[0027] Figure 2 Cross-sectional view of the cylinder of this utility model Figure 1 ;

[0028] Figure 3 Cross-sectional view of the cylinder of this utility model Figure 2 ;

[0029] Figure 4 This is a schematic diagram showing the setting of the pressure and temperature measurement interface of this utility model;

[0030] Figure 5 This is a schematic diagram of the upper cover of this utility model;

[0031] Figure 6 This is a schematic diagram of the lower end cover of this utility model;

[0032] Figure 7 This is a schematic diagram of the lifting eye screw in the upper end cover process of this utility model. Detailed Implementation

[0033] like Figure 1 , 2 As shown in Figure 3, this utility model proposes a cylinder that can be used for interstage separation of a launch vehicle, including: a lower end cover 1, a lower end flange 2, a cylinder barrel 3, an upper end flange 4, an upper end cover 5, a piston head 6, a piston rod 7, a double sealing ring 8, a double support ring 9, an air inlet 10, and an exhaust damping hole 13.

[0034] The piston head 6 and piston rod 7 are connected by threads to form an integral part of the internal structure of the cylinder and are located inside the cylinder barrel 3; the lower end cover 1 is installed on the end of the cylinder barrel 3 where the piston head 6 is located through the lower end flange 2, and the cavity formed between the lower end cover 1 and the piston head 6 is a rodless cavity; the double sealing ring 8 and the double support ring 9 are installed between the piston head 6 and the cylinder barrel 3 for sealing.

[0035] The upper end cover 5 is installed at the other end of the cylinder 3 via the upper end flange 4. The piston rod 7 passes through the center hole of the upper end cover 5. The cavity formed between the piston rod 7 and the cylinder 3 is a rod cavity. A double sealing ring 8 and a double support ring 9 are also provided between the upper end cover 5 and the piston rod 7.

[0036] Both the lower end cover 1 and the upper end cover 5 are provided with an air inlet 10 and an exhaust damping hole 13, which are used to inflate and exhaust the rodless chamber and the rod chamber, respectively.

[0037] like Figure 3 As shown, in the design of the double-seal ring 8, the first seal is the inner seal ring, which has a bidirectional sealing function, and the second seal is the outer seal ring, which has a bidirectional sealing function. The two seal rings of the double-seal ring 8 and the two support rings of the double-support ring 9 are alternately arranged to ensure the stress stability of the seal rings and prevent them from deforming during operation. This ensures their sealing performance while improving their lateral load-bearing capacity. The rodless cavity and the rod cavity are two independent and non-intersecting sealed cavities.

[0038] This invention employs a double-seal ring design (8) for sealing, balancing both sealing performance and low friction requirements, making it suitable for the aerospace field. Simultaneously, a double-support ring design (9) ensures the reliability of the double-seal rings (8). These two designs together meet the sealing requirements for aerodynamic separation between launch vehicle stages. Figure 3As shown, the use of double sealing rings 8 can prevent gas from communicating between the rodless chamber and the rod chamber, and prevent gas from communicating between the rod chamber and the outside.

[0039] Furthermore, since this utility model adopts a double support method between the two seals, it can prevent the piston rod 7 from deforming under the action of lateral force during operation, thereby improving its lateral load-bearing capacity while ensuring its sealing performance.

[0040] like Figure 4 As shown, both the lower end cover 1 and the upper end cover 5 are provided with a temperature measuring port 11 and a pressure measuring port 12, which are used to connect external temperature measuring equipment and pressure measuring equipment to measure the temperature and pressure in the rodless cavity and the rod cavity, respectively.

[0041] This invention integrates the air inlet and damping exhaust outlet into the upper and lower end caps, making the cylinder structure more compact and avoiding the risk of seal damage that would occur if the openings were designed on the cylinder barrel. The pressure and temperature measurement interfaces are also integrated into the upper and lower end caps, simplifying the launch vehicle's measurement system interface while allowing for the measurement of the temperature and pressure of the gas inside the cylinder.

[0042] like Figure 7 As shown, it also includes four eye bolts 14, a process plug 15, and a fuse 16;

[0043] A process plug 15 is installed on the end of the piston rod 7. One eye bolt 14 is installed on the process plug 15, and three eye bolts 14 are installed on the front end cover 7. The three eye bolts 14 installed on the front end cover 7 and the one eye bolt 14 installed on the process plug 15 are connected by a fuse 16. The three eye bolts 14 installed on the front end cover 7 are used for cylinder lifting.

[0044] like Figure 5 As shown, this utility model features an exhaust damping hole 13 designed on the upper end cover. This hole allows the gas in the rod chamber (the chamber with the piston rod) of the cylinder to communicate with the external ambient gas. By designing the diameter of the damping hole, the gas in the rod chamber can be discharged at different speeds during the piston's operation, thus enabling the piston to decelerate according to specified requirements and making the launch vehicle safer during interstage separation. The damping hole is designed with a plug; when the plug is closed, gas cannot be discharged. Therefore, whether to close the plug and designing different damping hole sizes can be determined according to the launch vehicle separation technology requirements. Figure 5 As shown.

[0045] Preferably, the exhaust damping hole 13 is designed with a plug to prevent gas from escaping when the plug is closed.

[0046] like Figure 6As shown, by pre-pressurizing the rodless chamber of the cylinder, the piston is kept in contact with the separated body with a certain pre-tightening force during the flight of the launch vehicle, thus achieving rapid separation of the launch vehicle.

[0047] This utility model of cylinder also considers the issue of fixing moving parts during product transportation, lifting, and flight conditions. It incorporates four process lifting eye bolts: one on the piston process plug and three on the front flange. The three eye bolts on the front flange facilitate cylinder lifting. By connecting the lifting eye bolts on the piston process plug and the three on the front flange using fuse 16, the cylinder piston is secured, meeting the requirements during transportation. After transportation and lifting are completed, during the final assembly stage of the launch vehicle, the process plug and lifting eye bolts can be removed to meet the requirements for final product use.

[0048] In operation, this invention connects the lower end cap to the first stage of the launch vehicle and the upper end cap to the second stage. Before separation, the rodless chamber is pre-stressed to ensure the piston maintains a certain pre-tightening contact with the separated components throughout the launch vehicle's flight. During separation, a large amount of high-pressure gas is briefly injected into the rodless chamber, propelling the piston with high thrust to separate the first and second stages. After separation, the cylinder detaches along with the first stage. The upper inflation port is used for repositioning the cylinder after it has been ejected during ground testing.

[0049] Compared to cylinders used in conventional industry, this new cylinder is designed for the aerospace field and boasts advantages such as high pressure, high thrust, high reliability, fast separation speed, and strong sealing, meeting the requirements of the aerospace industry. This cylinder is a component for achieving aerodynamic separation between launch vehicle stages, and its development directly promotes the advancement of domestic launch vehicle stage aerodynamic technology and reusable rocket technology.

[0050] The contents not described in detail in this utility model specification are existing technologies known to those skilled in the art.

Claims

1. A cylinder that can be used for interstage separation of a launch vehicle, characterized in that, include: Lower end cover (1), lower end flange (2), cylinder (3), upper end flange (4), upper end cover (5), piston head (6), piston rod (7), double sealing ring (8), double support ring (9), air inlet (10) and exhaust damping hole (13). The piston head (6) and piston rod (7) are connected by threads to form an integral part of the cylinder internal structure and are located inside the cylinder barrel (3); the lower end cover (1) is installed on the cylinder barrel (3) at one end where the piston head (6) is located through the lower end flange (2), and the cavity formed between the lower end cover (1) and the piston head (6) is a rodless cavity; double sealing rings (8) and double support rings (9) are installed between the piston head (6) and the cylinder barrel (3); The upper end cover (5) is installed on the other end of the cylinder (3) through the upper end flange (4). The piston rod (7) passes through the center hole of the upper end cover (5). The cavity formed between the piston rod (7) and the cylinder (3) is a rod cavity. A double sealing ring (8) and a double support ring (9) are also provided between the upper end cover (5) and the piston rod (7). Both the lower end cap (1) and the upper end cap (5) are provided with an air inlet (10) and an exhaust damping hole (13), which are used to inflate and exhaust the rodless chamber and the rod chamber, respectively.

2. A cylinder for interstage separation of a launch vehicle according to claim 1, characterized in that: In the design of the double sealing ring (8), the first seal is the inner sealing ring, which has the function of bidirectional sealing, and the second seal is the outer sealing ring, which also has the function of bidirectional sealing.

3. A cylinder for interstage separation of a launch vehicle according to claim 1, characterized in that: The two sealing rings of the double sealing ring (8) and the two support rings of the double support ring (9) are alternately arranged.

4. A cylinder for interstage separation of a launch vehicle according to claim 1, characterized in that: The rodless cavity and the rod cavity are two independent, non-communicating sealed cavities.

5. A cylinder for interstage separation of a launch vehicle according to claim 1, characterized in that: Temperature measuring port (11) and pressure measuring port (12) are provided on both the lower end cover (1) and the upper end cover (5), respectively, for connecting external temperature measuring equipment and pressure measuring equipment to measure the temperature and pressure in the rodless cavity and the rod cavity.

6. A cylinder for interstage separation of a launch vehicle according to claim 1, characterized in that: It also includes four eye bolts (14), a process plug (15), and a fuse (16). A process plug (15) is installed on the end of the piston rod (7), a lifting eye screw (14) is installed on the process plug (15), and three lifting eye screws (14) are installed on the upper end cover (5). The three lifting eye screws (14) installed on the upper end cover (5) and the one lifting eye screw (14) installed on the process plug (15) are connected by a fuse (16). The three lifting eye screws (14) installed on the upper end cover (5) are used for cylinder lifting.

7. A cylinder for interstage separation of a launch vehicle according to claim 1, characterized in that: Adjusting the diameter of the exhaust damping hole (13) in the upper cover allows the piston in the cylinder to discharge the air in the rod chamber at different speeds during operation, thereby enabling the piston to decelerate according to the specified requirements.

8. A cylinder for interstage separation of a launch vehicle according to claim 7, characterized in that: The exhaust damping hole (13) is provided with a plug, which prevents gas from being discharged when the plug is closed.

9. A cylinder for interstage separation of a launch vehicle according to claim 1, characterized in that: The rodless chamber of the cylinder is pre-pressurized so that the piston always maintains a certain preload force with the separated body during the flight of the launch vehicle.

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