Two-way automatic device with double-valve structure and closed circulation full-flow afterburning engine

Abstract

The invention relates to a two-way automatic device of a double-valve structure and a closed circulation full-flow afterburning engine, and relates to the field of rocket engines. A valve cavity is formed in a valve body, an inlet is formed in one end of the valve body, an outlet is formed in the other end of the valve body, and the inlet and the outlet are both communicated with the valve cavity; the small valve element, the first spring, the guide sleeve, the second spring and the large valve element abut against one another in sequence and are arranged in the valve cavity, the guide sleeve is fixed to the valve cavity in a sealed mode and provided with an overflowing hole penetrating through the two ends of the guide sleeve, one end of the small valve element abuts against or is separated from the inlet in a sealed mode, one end of the large valve element abuts against or is separated from the guide sleeve in a sealed mode, and the large valve element is provided with large valve element through holes penetrating through the two ends of the large valve element. The two-way automatic device has the functions of forward low-pressure opening, reverse low-pressure sealing and reverse high-pressure sealing, has the functions of high-pressure and low-pressure one-way sealing, simplifies an engine system, reduces valve types, and is more beneficial to general assembly layout of an engine.

Description

Technical Field

[0001] This invention relates to the field of rocket engines, specifically to a two-way automatic device with a dual-valve structure and a closed-cycle full-flow staged combustion engine. Background Technology

[0002] With increasingly fierce competition in aerospace technology, both domestic and international efforts are accelerating the development of closed-cycle, full-flow staged combustion engines. The most typical example internationally is SpaceX's Raptor engine, which has already completed flight tests with Starship. Currently, domestic engines have completed scaled-down hot-fire tests of multi-nozzle thrust chambers and oxygen-rich / fuel-rich gas generators. Closed-cycle, full-flow staged combustion engines possess key technologies such as high thrust, high coupling, deep thrust variation, multiple restarts, and reusability, providing robust power support for reusable launch vehicles and showing broad application prospects.

[0003] Closed-cycle full-flow afterburning engine has the characteristics of high chamber pressure and high performance. High chamber pressure means that engine components (valve, thrust chamber, turbopump) need to be able to work normally under high pressure. Ensuring dynamic and static seals under high pressure is the design challenge of each component. Overcoming the sealing problem under high and low pressure is the foundation for developing a high-performance full-flow afterburning cycle solution.

[0004] Currently, the operating pressure of open-cycle rich-fuel liquid oxygen methane engines in service in China is not high, with a maximum operating pressure of approximately 18 MPa. A single-seal, thermoplastic purge check valve can meet the operating requirements at this pressure. Closed-cycle full-flow afterburning engines, however, have a maximum operating pressure of 60 MPa, which is relatively high. The purge check valve operates throughout the engine purge, cycle precooling, and main engine operation processes, and should have the functions of opening forward at a low purge pressure of 0.2 MPa, closing reverse at a low cycle precooling pressure of 0.4 MPa, and closing reverse at a high main engine operating pressure of 60 MPa. Existing check valves cannot meet the requirements of higher operating pressures; therefore, ensuring opening and reverse sealing over a wide pressure range is a key challenge in the development of purge check valves. Summary of the Invention

[0005] The technical problem this invention aims to solve is how to meet the requirements of unidirectional opening and high / low pressure reverse closure sealing under a wide pressure band. The bidirectional automatic device with a double-valve structure of this invention is used in engine purging, circulating precooling, and main engine operation processes. It is a low-temperature, high-pressure bidirectional automatic device with advantages such as a double-seat structure and high / low pressure sealing.

[0006] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: A bidirectional automatic device with a double valve structure includes a valve body, a small valve core, a guide sleeve, a large valve core, a first spring, and a second spring. The valve body has a valve cavity. One end of the valve body has an inlet, and the other end has an outlet. Both the inlet and the outlet are connected to the valve cavity. The small valve core, the first spring, the guide sleeve, the second spring, and the large valve core are sequentially abutted and disposed in the valve cavity. The guide sleeve is sealed and fixed to the valve cavity and has a flow hole penetrating through both ends of the guide sleeve. One end of the small valve core is sealed and abutted or separated from the inlet, and one end of the large valve core is sealed and abutted or separated from the guide sleeve. The large valve core has a large valve core through hole penetrating through both ends of the large valve core.

[0007] The beneficial effects of this invention are: the double valve structure bidirectional automatic device is a bidirectional automatic device with a double valve seat structure, which has the advantages of wide working pressure range, reliable operation, and simplified engine system, and works in the entire process of engine blow-off, circulating precooling, main engine operation, and shutdown.

[0008] This bidirectional automatic device has forward low-pressure opening, reverse low-pressure sealing and reverse high-pressure sealing functions, and also has high-pressure and low-pressure unidirectional sealing functions, which simplifies the engine system, reduces the number of valve types, and is more conducive to the engine assembly layout.

[0009] Specifically, during engine purging, low-pressure medium flows in from the inlet, overcoming the elastic force of the first spring to push the small valve core to separate from the inlet, and the bidirectional automatic valve opens at low pressure.

[0010] During engine pre-cooling, a low-pressure medium is introduced from the outlet. The pressure difference generated by the medium at both ends of the large valve core is insufficient to overcome the elastic force of the second spring, so the large valve core will not move towards the guide sleeve and seal against it. The low-pressure medium flows through the through hole and flow hole of the large valve core to the small valve core, generating a pressure difference force at both ends of the small valve core. The pressure difference force and the elastic force of the first spring are transmitted to the small valve core, causing the small valve core to come into contact with the inlet seal, ensuring the low-pressure reverse sealing of the bidirectional automatic device.

[0011] When the engine is working, a high-pressure medium is introduced instantaneously from the outlet. The high-pressure medium flows into the valve chamber through the through hole of the large valve core. Due to the throttling effect, a certain medium pressure difference is generated at both ends of the large valve core. The medium pressure difference overcomes the elastic force of the second spring, causing the large valve core to move towards the guide sleeve and fit and seal with the guide sleeve, ensuring the reverse high-pressure seal of the bidirectional automatic device.

[0012] Based on the above technical solution, the present invention can be further improved as follows.

[0013] Furthermore, it also includes a small valve core sealing ring, and the edge of the inlet facing the valve cavity has a sealing protrusion. The small valve core sealing ring is in sealing contact with or separates from the small valve core and the sealing protrusion.

[0014] The beneficial effects of adopting the above-mentioned further solution are: the small valve core is sealed to the inlet by the small valve core sealing ring and the sealing protrusion. After the small valve core is subjected to the pressure of the medium coming in from the outlet and the elastic force of the first spring, the sealing protrusion is pressed into the small valve core sealing ring. The small valve core sealing ring deforms and fits tightly with the sealing protrusion to ensure sealing performance.

[0015] Furthermore, one end of the guide sleeve has a guide sleeve countersunk hole, the first spring is disposed in the guide sleeve countersunk hole, and the other end of the small valve core slides in cooperation with the guide sleeve countersunk hole and abuts against one end of the first spring.

[0016] The beneficial effect of adopting the above-mentioned further solution is that the guide sleeve countersunk hole can limit and guide the small valve core and the first spring.

[0017] Furthermore, it also includes a first spring energy storage sealing ring. One end of the guide sleeve countersunk hole has a guide sleeve annular groove. The first spring energy storage sealing ring is embedded in the guide sleeve annular groove and seals against the side wall of the small valve core.

[0018] The beneficial effects of adopting the above-mentioned further solution are: the first spring energy storage sealing ring prevents the medium from entering the guide sleeve counterbore, so that the end faces of the two ends of the small valve core can generate a pressure difference due to the medium flowing in at the inlet, which overcomes the elastic force of the first spring, ensures that the bidirectional automatic device maintains a low-pressure fully open state, and prevents chattering.

[0019] Furthermore, the valve body has a leak detection port on its side wall, and the guide sleeve has a guide sleeve leak detection port on its side wall. The leak detection port, the guide sleeve leak detection port, and the guide sleeve countersunk hole are connected in sequence.

[0020] The beneficial effects of adopting the above-mentioned further solution are: setting leak detection ports and guide sleeve leak detection ports can detect whether there is media flowing into the guide sleeve countersunk hole, thereby testing the sealing performance of the first spring energy storage sealing ring. At the same time, it can prevent the formation of a dead cavity in the guide sleeve countersunk hole and prevent the small valve core from getting stuck due to the pressure inside the guide sleeve countersunk hole.

[0021] Furthermore, it also includes graphite sealing gaskets, the inner wall of the valve cavity has an annular guide sleeve positioning groove, the outer wall of the guide sleeve has a guide sleeve positioning protrusion, the guide sleeve positioning protrusion is located in the annular guide sleeve positioning groove, there are two graphite sealing gaskets, the two graphite sealing gaskets are respectively located at both ends of the guide sleeve positioning protrusion, and the guide sleeve positioning protrusion is sealed with the annular guide sleeve positioning groove.

[0022] The beneficial effect of adopting the above-mentioned further solution is that the graphite sealing gasket fixes the position of the guide sleeve, while ensuring the static seal between the guide sleeve and the inner wall of the valve cavity.

[0023] Furthermore, one end of the large valve core has a large valve core countersunk hole, the second spring is located in the large valve core countersunk hole, one end edge of the large valve core countersunk hole has a first conical surface, the other end of the guide sleeve has a second conical surface, and the first conical surface and the second conical surface are sealed and abutted or separated.

[0024] The beneficial effect of adopting the above-mentioned further solution is that the first conical surface and the second conical surface form a metal conical seal, blocking the flow of the outlet medium into the valve cavity and achieving reverse high-pressure sealing.

[0025] Furthermore, it also includes a second spring energy storage sealing ring. The other end of the large valve core has a large valve core protrusion in the middle. The second spring energy storage sealing ring is sleeved on the outside of the large valve core protrusion and seals against the inner wall of the valve cavity.

[0026] The beneficial effect of adopting the above-mentioned further solution is to prevent the medium at the outlet from flowing between the guide sleeve and the inner wall of the valve cavity, thus forming a dynamic seal.

[0027] Furthermore, the end of the large valve core protruding outward toward the outlet has a limiting protrusion.

[0028] The beneficial effect of adopting the above-mentioned further solution is that the limiting protrusion leaves a gap between the outer convex end face of the large valve core and the end face of the valve cavity. After the high pressure medium flows into the outlet, some of the medium can flow into the gap, thereby forming a pressure difference at both ends of the large valve core. Under the action of the pressure difference, the large valve core moves to seal against the guide sleeve.

[0029] The present invention also provides a closed-cycle full-flow afterburning engine, including a two-way automatic device with a dual-valve structure.

[0030] The beneficial effects of this invention are as follows: This invention proposes a bidirectional automatic device with a dual valve seat structure and a dual valve structure that can be applied to a full-flow afterburning engine. It has the advantages of a wide working pressure range, reliable operation, and simplified engine system. It works throughout the entire process of engine purging, circulating precooling, main engine operation, and shutdown.

[0031] This bidirectional automatic device adopts two sealing types: metal conical surface seal (first and second conical surfaces) and non-metallic seal (small valve core sealing ring and sealing protrusion). It can achieve effective reverse sealing within the range of (0-60) MPa, has a wide working pressure range, and reliable performance. It can be applied to various stages of closed-loop full-flow afterburning engine purging, circulating precooling, main engine operation, shutdown and thrust adjustment.

[0032] This bidirectional automatic device has forward low-pressure opening, reverse low-pressure sealing and reverse high-pressure sealing functions, and also has high-pressure and low-pressure unidirectional sealing functions, which simplifies the engine system, reduces the number of valve types, and is more conducive to the engine assembly layout.

[0033] Using spring sealing rings instead of traditional bellows as dynamic seals for ultra-low temperature and high pressure media provides good low-temperature sealing performance. The bidirectional automatic device has a simple structure and small size. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the structure of a two-way automatic device with a double-door structure according to the present invention;

[0035] Figure 2 This is a schematic diagram of a bidirectional automatic device with a double-valve structure according to the present invention in the state of engine purging and positive low-pressure opening.

[0036] Figure 3 This is a schematic diagram of a bidirectional automatic device with a double valve structure according to the present invention in the engine cycle pre-cooling and reverse low-pressure closed state;

[0037] Figure 4 This is a schematic diagram of a bidirectional automatic device with a double-valve structure according to the present invention in the state of engine main unit operation and reverse high pressure shutdown;

[0038] Figure 5 for Figure 1 A magnified view of part X of a two-way automaton with a double-door structure.

[0039] The attached diagram lists the components represented by each number as follows:

[0040] 1. Housing; 2. First spring energy storage sealing ring; 3. Small valve core; 4. Graphite sealing gasket; 5. Cover; 6. First spring; 7. Large valve core; 701. Large valve core through hole; 702. Large valve core countersunk hole; 703. First conical surface; 704. Large valve core protrusion; 8. Second spring energy storage sealing ring; 9. Second spring; 10. Guide sleeve; 101. Flow hole; 102. Guide sleeve countersunk hole; 103. Guide sleeve leak detection port; 104. Second conical surface; 11. Double-ended stud; 12. Flat washer; 13. Saddle spring washer; 14. Nut; 15. Inlet; 16. Outlet; 17. Leak detection port; 18. Small valve core sealing ring. Detailed Implementation

[0041] The principles and features of the present invention are described below. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0042] like Figures 1-5As shown, this embodiment provides a bidirectional automatic device with a double-valve structure, including a valve body, a small valve core 3, a guide sleeve 10, a large valve core 7, a first spring 6, and a second spring 9. The valve body has a valve cavity, with an inlet 15 at one end and an outlet 16 at the other end. Both the inlet 15 and the outlet 16 are connected to the valve cavity. The small valve core 3, the first spring 6, the guide sleeve 10, the second spring 9, and the large valve core 7 are sequentially abutted and disposed within the valve cavity. The guide sleeve 10 is sealed and fixed to the valve cavity and has flow holes 101 penetrating both ends of it. One end of the small valve core 3 is sealed and abutted or separated from the inlet 15, and one end of the large valve core 7 is sealed and abutted or separated from the guide sleeve 10. The large valve core 7 has a large valve core through hole 701 penetrating both ends of it.

[0043] The double-valve structure bidirectional automatic device is a bidirectional automatic device with a double valve seat structure, used to replace the existing blow-out check valve. It has the advantages of wide working pressure range, reliable operation, and simplified engine system. It works in the entire process of engine blow-out, circulation precooling, main engine operation, and shutdown.

[0044] This bidirectional automatic device has forward low-pressure opening, reverse low-pressure sealing, and reverse high-pressure sealing functions, and also has high-pressure and low-pressure one-way sealing functions, simplifying the engine system, reducing valve types, and making it more conducive to the engine assembly layout. Specifically, in existing engine systems, without using the bidirectional automatic device of this embodiment, two types of one-way valves are required, and the system needs to add two or three branches; however, by using the bidirectional automatic device of this application, the system only needs to add one branch to install this bidirectional automatic device to meet the system functions.

[0045] Specifically, during engine purging, low-pressure medium flows in from inlet 15, overcoming the elastic force of the first spring 6 to push the small valve core 3 to separate from inlet 15, and the bidirectional automatic valve opens at low pressure.

[0046] During engine pre-cooling, a low-pressure medium is introduced from outlet 16. The pressure difference generated by the medium at both ends of the large valve core 7 is insufficient to overcome the elastic force of the second spring 9. The large valve core 7 will not move towards the guide sleeve 10 and will not seal against the guide sleeve 10. The low-pressure medium flows through the large valve core through hole 701 and the flow hole 101 to the small valve core 3, generating a pressure difference force at both ends of the small valve core 3. The pressure difference force and the elastic force of the first spring 6 are transmitted to the small valve core 3, making the small valve core 3 seal against the inlet 15, ensuring the low-pressure reverse sealing of the bidirectional automatic device.

[0047] When the engine is working, a high-pressure medium is introduced instantaneously from outlet 16. The high-pressure medium flows into the valve cavity through the large valve core through hole 701. Due to the throttling effect, a certain medium pressure difference is generated at both ends of the large valve core 7. The medium pressure difference overcomes the elastic force of the second spring 9, causing the large valve core 7 to move towards the guide sleeve 10 and fit and seal with the guide sleeve 10, ensuring the reverse high-pressure seal of the bidirectional automatic device.

[0048] Specifically, the valve body includes a housing 1 and a cover 5, which are connected by a flange structure, forming a valve cavity between them. The connection structure between the housing 1 and the cover 5 is as follows: one end of a double-ended stud 11 is threaded to the flange of the housing 1, and the other end passes through a saddle-shaped spring washer 13 and a flat washer 12, and is threaded to a nut 14. The double-ended stud 11, the saddle-shaped spring washer 13, the flat washer 12, and the nut 14 constitute a set of connecting assemblies, and multiple sets of connecting assemblies are spaced apart along the circumference of the housing 1.

[0049] Specifically, the inlet end face of the housing 1 and the outlet end face of the cover 5 are both machined with four threaded holes evenly distributed along the circumference of the valve body and the valve body annular sealing groove. A graphite sealing gasket is installed in the valve body annular sealing groove and connected to the engine system pipeline.

[0050] Based on the above technical solution, a small valve core sealing ring 18 is also included. The edge of the inlet 15 facing the valve cavity has a sealing protrusion. The small valve core sealing ring 18 and the small valve core 3 end are in sealing contact or separation with the sealing protrusion.

[0051] One end of the small valve core 3 is sealed to the inlet 15 by the small valve core sealing ring 18 and the sealing protrusion. After the small valve core 3 is subjected to the pressure of the medium coming in from the outlet 16 and the elastic force of the first spring 6, the sealing protrusion is pressed into the small valve core sealing ring 18. The small valve core sealing ring 18 deforms and fits tightly with the sealing protrusion to ensure sealing performance.

[0052] Specifically, such as Figure 5 As shown, the cross-section of the small valve core sealing ring 18 is convex.

[0053] Based on the above technical solution, one end of the guide sleeve 10 has a guide sleeve countersunk hole 102, the first spring 6 is disposed in the guide sleeve countersunk hole 102, and the other end of the small valve core 3 is slidably engaged with the guide sleeve countersunk hole 102 and abuts against one end of the first spring 6.

[0054] The guide sleeve countersunk hole 102 limits and guides the small valve core 3 and the first spring 6.

[0055] Specifically, the outer circular surface of the small valve core 3 should have high machining accuracy, and together with the guide sleeve countersunk hole 102 of the guide sleeve 10, they form a key motion pair.

[0056] Based on the above technical solution, it also includes a first spring energy storage sealing ring 2. One end of the guide sleeve countersunk hole 102 has a guide sleeve annular groove. The first spring energy storage sealing ring 2 is embedded in the guide sleeve annular groove and seals with the side wall of the small valve core 3.

[0057] The first spring energy storage sealing ring 2 prevents the medium from entering the guide sleeve counterbore 102, so that the two end faces of the small valve core 3 can generate a pressure difference due to the medium flowing in from the inlet 15, which overcomes the elastic force of the first spring 6, ensures that the bidirectional automatic device maintains a low-pressure fully open state, and prevents chattering.

[0058] Based on the above technical solution, the side wall of the valve body has a leak detection port 17, the side wall of the guide sleeve 10 has a guide sleeve leak detection port 103, and the leak detection port 17, the guide sleeve leak detection port 103 and the guide sleeve countersunk hole 102 are connected in sequence.

[0059] The leak detection port 17 and the guide sleeve leak detection port 103 are provided to detect whether there is media flowing into the guide sleeve countersunk hole 102, thereby detecting the sealing performance of the first spring energy storage sealing ring 2. At the same time, it can prevent the formation of a dead cavity in the guide sleeve countersunk hole 102 and prevent the small valve core 3 from getting stuck due to the pressure inside the guide sleeve countersunk hole 102.

[0060] Based on the above technical solution, it also includes a graphite sealing gasket 4. The inner wall of the valve cavity has an annular guide sleeve positioning groove, and the outer wall of the guide sleeve 10 has a guide sleeve positioning protrusion. The guide sleeve positioning protrusion is located in the annular guide sleeve positioning groove. There are two graphite sealing gaskets 4, which are located at the two ends of the guide sleeve positioning protrusion, and seal the guide sleeve positioning protrusion with the annular guide sleeve positioning groove.

[0061] The graphite sealing gasket 4 fixes the position of the guide sleeve 10 and ensures a static seal between the guide sleeve 10 and the inner wall of the valve cavity.

[0062] Specifically, the outer wall of the guide sleeve positioning protrusion has an annular guide groove, and both the guide sleeve leak detection port 103 and leak detection port 17 are connected to the annular guide groove. Thus, if the graphite gasket 4 fails to seal, the medium will flow into the annular guide groove, allowing leakage to be detected through the leak detection port 17. Simultaneously, it can also be used to detect whether medium is flowing into the guide sleeve countersunk hole 102.

[0063] Specifically, the annular guide sleeve positioning groove is located at the end of the housing 1 away from the inlet 15. After the housing 1 and the cover 5 are assembled, a graphite sealing gasket 4, the guide sleeve positioning protrusion and another graphite sealing gasket 4 are pressed into the annular guide sleeve positioning groove in sequence.

[0064] Based on the above technical solution, one end of the large valve core 7 has a large valve core countersunk hole 702, the second spring 9 is located in the large valve core countersunk hole 702, one end edge of the large valve core countersunk hole 702 has a first conical surface 703, the other end of the guide sleeve 10 has a second conical surface 104, and the first conical surface 703 and the second conical surface 104 are sealed and abutted or separated.

[0065] The first conical surface 703 and the second conical surface 104 form a metal conical seal, blocking the flow of medium from outlet 16 into the valve cavity, thus achieving a reverse high-pressure seal.

[0066] Specifically, the bottom of the large valve core countersunk hole 702 (the end of the large valve core countersunk hole 702 facing the outlet 16) has the large valve core through hole 701.

[0067] Specifically, the outer diameter of the other end of the guide sleeve 10 is smaller than the outer diameter of one end of the large valve core 7.

[0068] Based on the above technical solution, a second spring energy storage sealing ring 8 is also included. The other end of the large valve core 7 has a large valve core protrusion 704 in the middle. The second spring energy storage sealing ring 8 is sleeved on the outside of the large valve core protrusion 704 and seals with the inner wall of the valve cavity.

[0069] To prevent the medium at outlet 16 from flowing between the guide sleeve 10 and the inner wall of the valve cavity, thus forming a dynamic seal.

[0070] Based on the above technical solution, the end of the large valve core protrusion 704 facing the outlet 16 has a limiting protrusion.

[0071] The limiting protrusion leaves a gap between the end face of the large valve core's outer protrusion 704 and the end face of the valve cavity. After the high-pressure medium flows into the outlet 16, some of the medium can flow into this gap, thereby creating a pressure difference between the two ends of the large valve core 7. Under the action of the pressure difference, the large valve core 7 moves to seal against the guide sleeve 10.

[0072] Optionally, the limiting protrusion can be a dot-shaped protrusion or a strip-shaped protrusion.

[0073] The working principle of the bidirectional automatic device with a double-door structure in this embodiment is as follows:

[0074] During engine purging, low-pressure medium flows into the housing 1 through inlet 15, overcoming the pre-installed force of the first spring 6, and the bidirectional automatic device opens under low pressure. The first spring energy storage seal ring 2 blocks the flow of low-pressure medium to the guide sleeve countersunk hole 102 of the small valve core 3 and the guide sleeve 10, creating a pressure difference between the left and right end faces of the small valve core 3, overcoming the working force of the first spring 6, ensuring that the bidirectional automatic device maintains the fully open low-pressure state, and preventing chatter.

[0075] During engine pre-cooling, a low-pressure medium is introduced from outlet 16 of cover 5. The pressure difference generated by the medium at both ends of the large valve core 7 is insufficient to overcome the pre-installation force of the second spring 9, and the large valve core 7 will not move to the left to seal against the guide sleeve 10. The low-pressure medium flows into the inner cavity between the housing 1 and the guide sleeve 10, acting on the left and right end faces of the small valve core 3 (the annular area of ​​the right end of the small valve core 3 is larger than that of the left end, where the annular area of ​​the left end refers to the area of ​​the left end of the small valve core 3 minus the cross-sectional area of ​​the inlet 15), generating a medium pressure difference. The medium pressure difference and the pre-installation force of the first spring 6 are jointly transmitted to the small valve core 3, causing the non-metallic sealing surface of the small valve core 3 to be pressed tightly against the valve seat of the housing 1 (e.g., Figure 5 As shown), ensure the low-pressure reverse sealing of the bidirectional automatic device.

[0076] When the engine is working, high-pressure medium is introduced instantaneously from the outlet 16 of the cover 5. The second spring energy storage seal ring 8 blocks the high-pressure medium from flowing into the inner cavity between the cover 5 and the guide sleeve 10. The high-pressure medium flows into the valve cavity through the large valve core through hole 701 of the large valve core 7. Due to the throttling effect, a certain medium pressure difference is generated on the left and right end faces of the large valve core 7. The medium pressure difference overcomes the working force of the second spring 9, causing the large valve core 7 to move to the left and fit and seal with the conical inclined surface (second conical surface 104) of the guide sleeve 10, ensuring the reverse high-pressure seal of the bidirectional automatic device.

[0077] This embodiment also provides a closed-cycle full-flow afterburning engine, including a two-way automatic device with a dual-valve structure.

[0078] Specifically, the valve body's inlet 15 and outlet 16 are connected to and communicate with the engine system piping.

[0079] In the description of this invention, it should be noted that the terms "axial", "radial", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0080] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0081] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0082] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0083] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0084] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A two-way automatic machine with a double-valve structure, characterized in that: The invention comprises a valve body, a small valve core (3), a guide sleeve (10), a large valve core (7), a first spring (6) and a second spring (9), wherein the valve body has a valve cavity, one end of the valve body has an inlet (15), and the other end thereof has an outlet (16), the inlet (15) and the outlet (16) are both connected to the valve cavity, the small valve core (3), the first spring (6), the guide sleeve (10), the second spring (9) and the large valve core (7) are sequentially abutted and arranged in the valve cavity, the guide sleeve (10) is sealed and fixed to the valve cavity, and has a flow hole (101) passing through both ends thereof, one end of the small valve core (3) is sealed abutted or separated from the inlet (15), one end of the large valve core (7) is sealed abutted or separated from the guide sleeve (10), and the large valve core (7) has a large valve core through hole (701) passing through both ends thereof.

2. A two-way automatic machine with a double-valve structure according to claim 1, characterized in that: It also includes a small valve core sealing ring (18), the edge of the inlet (15) facing one end of the valve cavity has a sealing protrusion, the small valve core sealing ring (18) and one end of the small valve core (3), the small valve core sealing ring (18) and the sealing protrusion are sealed or separated.

3. A two-way automatic machine with a double-sliding door structure according to claim 1, characterized in that: One end of the guide sleeve (10) has a guide sleeve counterbore (102), the first spring (6) is arranged in the guide sleeve counterbore (102), and the other end of the small valve core (3) is slidably matched with the guide sleeve counterbore (102) and abuts against one end of the first spring (6).

4. A two-way automatic machine with a double-sliding door structure according to claim 3, characterized in that: It also includes a first spring energy storage sealing ring (2), one end of the guide sleeve counterbore (102) has a guide sleeve annular groove, the first spring energy storage sealing ring (2) is embedded in the guide sleeve annular groove and seals with the side wall of the small valve core (3).

5. A two-way automatic machine with a double-sliding door structure according to claim 3, characterized in that: The side wall of the valve body has a leak detection port (17), the side wall of the guide sleeve (10) has a guide sleeve leak detection port (103), and the leak detection port (17), the guide sleeve leak detection port (103) and the guide sleeve counterbore (102) are sequentially connected.

6. A two-way automatic machine with a double valve structure according to claim 1, characterized in that: It also includes a graphite sealing gasket (4), the inner wall of the valve cavity has an annular guide sleeve positioning groove, the outer wall of the guide sleeve (10) has a guide sleeve positioning protrusion, the guide sleeve positioning protrusion is located in the annular guide sleeve positioning groove, and there are two graphite sealing gaskets (4), the two graphite sealing gaskets (4) are respectively located at the two ends of the guide sleeve positioning protrusion, and the guide sleeve positioning protrusion is sealed with the annular guide sleeve positioning groove.

7. A two-way automatic machine with a double valve structure according to claim 1, characterized in that: One end of the large valve core (7) has a large valve core counterbore (702), the second spring (9) is located in the large valve core counterbore (702), one end edge of the large valve core counterbore (702) has a first conical surface (703), the other end of the guide sleeve (10) has a second conical surface (104), the first conical surface (703) and the second conical surface (104) are sealed in contact or separated.

8. A two-way automatic machine with a double valve structure according to claim 1, characterized in that: It also includes a second spring energy storage sealing ring (8), and the middle part of the other end of the large valve core (7) has a large valve core outer protrusion (704). The second spring energy storage sealing ring (8) is sleeved on the outside of the large valve core outer protrusion (704) and is sealed with the inner wall of the valve cavity.

9. A two-way automatic machine with a double-sliding door structure according to claim 8, characterized in that: One end of the outer protrusion (704) of the large valve core facing the outlet (16) has a limiting protrusion.

10. A closed cycle full flow afterburning engine, characterized in that: A two-way automatic machine comprising a double valve structure as described in any one of claims 1-9.

Images