A valve structure for purging and switching of a rocket engine and a rocket

Abstract

The present invention provides a valve structure and a rocket for rocket engine purge switching. The valve structure includes: a housing, a sleeve, and a valve cover; the housing is fixedly connected to the sleeve to form a first cavity; the housing is provided with a rocket purge inlet communicating the first cavity and the on-board purge system along its axial direction; a first valve core is arranged in the first cavity; a first elastic element is arranged between the first valve core and the sleeve; the sleeve is fixedly connected to the valve cover to form a second cavity, and the valve cover is provided with a ground purge inlet communicating the second cavity and the ground purge system; the sleeve is provided with a first purge hole communicating the first cavity and the second cavity; a second valve core is arranged in the second cavity, and the second valve core is in clearance fit with the second cavity, and a second elastic element is arranged between the second valve core and the sleeve; the housing is further provided with a purge outlet communicating the first cavity and the rocket engine. This valve structure simplifies the structure of the engine purge system.

Description

Technical Field

[0001] The present invention relates to the field of rockets, and particularly to a valve structure for blowdown switching of a rocket engine. Background Art

[0002] Before a space vehicle (such as a rocket) takes off, it is necessary to fill its engine with cryogenic propellant. Before and after filling with cryogenic propellant, it is necessary to blow down the engine to prevent water vapor in the air from entering the engine and causing icing problems. Since the blowdown gas cylinders carried by the rocket cannot maintain long-term blowdown of the engine, it is necessary to connect the ground gas supply system to the engine blowdown system to blow it down before the rocket is launched. Just before the rocket is launched, the on-board gas cylinder is switched to blow down the engine. Check valves are provided in the ground blowdown system and the on-board system to prevent gas from flowing back and forth during blowdown. Generally, three check valves are required to complete the blowdown of the dual propellants. In this way, not only are there a large number of check valves, but the engine structure, layout, etc. are also more complex, making it difficult to meet the requirements of commercial spaceflight.

[0003] To simplify the blowdown system or the engine system structure to achieve the switching between ground blowdown and on-board blowdown functions, it is particularly important to design a valve structure for blowdown switching of a rocket engine. Summary of the Invention

[0004] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a valve structure for blowdown switching of a rocket engine.

[0005] The present invention provides a valve structure for rocket engine purge switching, comprising: a housing, a sleeve and a valve cover; the housing is fixedly connected to the sleeve to form a first cavity; the housing is provided with an on-board purge inlet communicating the first cavity and the on-board purge system along its axial direction for introducing the gas of the on-board purge system into the first cavity; a first valve core is arranged in the first cavity, and the first valve core is in clearance fit with the first cavity; a first elastic element is arranged between the first valve core and the sleeve, and the first valve core abuts against the on-board purge inlet under the elastic action of the first elastic element to seal the on-board purge inlet; the sleeve is fixedly connected to the valve cover to form a second cavity, the valve cover is provided with a ground purge inlet communicating the second cavity and the ground purge system for introducing the gas of the ground purge system into the second cavity; the sleeve is provided with a first purge hole communicating the first cavity and the second cavity; a second valve core is arranged in the second cavity, the second valve core is in clearance fit with the second cavity, a second elastic element is arranged between the second valve core and the sleeve, and the second valve core abuts against the ground purge inlet under the elastic action of the second elastic element to seal the ground purge inlet; the housing is further provided with a purge outlet communicating the first cavity and the rocket engine for discharging the gas in the first cavity to the rocket engine; when the on-board purge system ventilates the on-board purge inlet, the gas acts on the first valve core to make it move in a direction away from the on-board purge inlet to open the on-board purge inlet, and the gas enters the first cavity and flows out from the purge outlet to the rocket engine to purge the rocket engine; when the ground purge system ventilates the ground purge inlet, the gas acts on the second valve core to make it move in a direction away from the ground purge inlet to open the ground purge inlet, the gas enters the second cavity, enters the first cavity from the first purge hole and flows out from the purge outlet to the rocket engine to purge the rocket engine.

[0006] According to an embodiment of the present invention, the first valve core is provided with an inclined cut surface in its circumferential direction; the circumferential surface of the first valve core fits against the inner wall of the housing and can slide relative thereto to perform circumferential limit on the first valve core; a flat gap is formed between the inclined cut surface of the first valve core and the inner wall of the housing for the gas to flow in the first cavity when the first valve core is away from the on-board purge inlet.

[0007] According to an embodiment of the present invention, a first non-metallic sealing surface is arranged on the opposite surface of the first valve core and the housing at the on-board purge inlet for sealing between the first valve core and the on-board purge inlet when the first valve core abuts against the on-board purge inlet.

[0008] According to an embodiment of the present invention, a second non-metallic sealing surface is provided on the opposite surface of the first valve core and the sleeve at the first purge hole for sealing between the first valve core and the first purge hole when the first valve core abuts against the first purge hole.

[0009] According to an embodiment of the present invention, the valve cover includes a guide sleeve fixedly arranged circumferentially along its inner wall, and the guide sleeve is provided with a guide hole; the guide hole is used for placing the second valve core to perform circumferential limit on it; the second valve core is of a T-shaped structure; the guide sleeve is provided with a second purge hole communicating the ground purge inlet and the second cavity along its circumferential direction, and the second valve core moves axially along the guide hole to open or close the second purge hole.

[0010] According to an embodiment of the present invention, a plurality of the second purge holes are provided along the circumferential direction of the guide sleeve.

[0011] According to an embodiment of the present invention, the sleeve includes a base fixedly arranged circumferentially along its inner wall, and the base divides the second cavity into a first sub-cavity and a second sub-cavity along its axial direction; the second elastic element is arranged between the second valve core and the base; the base is provided with a third purge hole along its circumferential direction for communicating the first sub-cavity and the second sub-cavity; when the ground purge system ventilates the ground purge inlet, the second valve core moves towards the base, and the gas enters the second sub-cavity from the ground purge inlet through the second purge hole, then enters the first sub-cavity through the third purge hole, and enters the first cavity from the first sub-cavity through the first purge hole, and then flows out from the purge outlet.

[0012] According to an embodiment of the present invention, a plurality of the third purge holes are provided along the circumferential direction of the base; when the second valve core abuts against the base, the third purge holes are avoided.

[0013] According to an embodiment of the present invention, a third non-metallic sealing surface is provided at the mating position of the second valve core and the guide sleeve for sealing between the two.

[0014] On the other hand, the present invention provides a rocket including the above valve structure.

[0015] According to the valve structure for rocket engine purge switching of the present invention, one valve structure is used for oxygen circuit purge, and one valve structure is used for fuel circuit purge, that is, only two valve structures provided in this embodiment need to be applied to the purge system to realize the switching function of the on-board purge circuit and the ground purge circuit purge system. The valve structure of the present application simplifies the structure of the engine purge system and solves the problems of a large number of check valves in the purge system, complex engine structure and layout.

[0016] It should be understood that the above general description and the following specific embodiments are only exemplary and explanatory, and do not limit the scope of what the present invention claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The following drawings are a part of the specification of the present invention, which illustrate exemplary embodiments of the present invention. The attached drawings, together with the description of the specification, are used to explain the principles of the invention.

[0018] Figure 1 is a cross-sectional view of a valve structure for rocket engine purge switching according to an embodiment of the present invention;

[0019] Figure 2 is a schematic diagram of a traditional rocket engine propellant purge system;

[0020] Figure 3 is a cross-sectional view of the valve structure during ground purge according to an embodiment of the present invention;

[0021] Figure 4 is a cross-sectional view of the valve structure during in-flight purge according to an embodiment of the present invention;

[0022] Figure 5 is a schematic diagram of a rocket engine propellant purge system according to an embodiment of the present invention;

[0023] Figure 6 is Figure 1 a cross-sectional view taken along the A-A direction in

[0024] Figure 7 is Figure 1 an enlarged view of B in

[0025] Description of the Reference Numerals:

[0026] 1 - housing; 2 - first valve core; 3 - first elastic element; 4 - valve cover; 5 - sleeve; 6 - guide sleeve; 7 - second valve core; 8 - second elastic element; 9 - base; 10 - first cavity; 11 - in-flight purge inlet; 12 - ground purge inlet; 13 - first purge hole; 14 - purge outlet; 15 - inclined plane; 16 - first non-metallic sealing surface; 17 - second non-metallic sealing surface; 18 - guide hole; 19 - second purge hole; 20 - first sub-cavity; 21 - second sub-cavity; 22 - third purge hole; 23 - purge check valve. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] The features and exemplary embodiments of various aspects of the present invention will be described in detail below. To make the objectives, technical solutions, and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only configured to explain the present invention and are used to exemplarily illustrate the principles of the present invention, and are not configured to limit the present invention. Additionally, the components in the drawings are not necessarily drawn to scale. For example, the sizes of some components or regions in the drawings may be enlarged for other components or regions to assist in understanding the embodiments of the present invention.

[0028] The directional terms that appear in the following description are all the directions shown in the figures and do not limit the specific structure of the embodiments of the present invention. In the description of the present invention, it should be noted that unless otherwise specified, the terms "mounted", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection. It can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] In addition, the terms "comprising", "including", "having", or any other variant thereof are intended to cover non-exclusive inclusion, such that a structure or component including a series of elements not only includes those elements but also other elements that are not explicitly listed or are inherent to the structure or component. Without further limitation, an element defined by the statement "including..." does not exclude the existence of additional identical elements in the article or device including the element.

[0030] Spatial relationship terms such as "below", "beneath", "under", "lower", "above", "over", "upper", etc. are used to facilitate description to explain the positioning of one element relative to a second element and are intended to cover different orientations of the device in addition to the orientations shown in the figures. Additionally, for example, "one element is on / under another element" can mean that the two elements are in direct contact or that there are other elements between the two elements. Furthermore, terms such as "first", "second", etc. are also used to describe various elements, regions, parts, etc. and do not particularly refer to an order or sequence and should not be construed as limiting. Similar terms represent similar elements throughout the description.

[0031] In the process of describing the present invention below, in certain scenario descriptions, only "rocket", "launch vehicle", "spacecraft", "space launch vehicle" or "missile" may be used. This is only for convenience of description, and its connotation is not limited to the specific words used. Generally, the space launch vehicle of the present invention includes not only launch vehicles, space launch vehicles, rockets for carrying satellites, spacecraft or other detectors, but also various missiles, rockets and other weapons for carrying military payloads, as well as similar products capable of sending payloads into the air. When those skilled in the art interpret the above specific words, they shall not limit the launch vehicle to only one of the launch rocket or missile according to the specific words used in the description scenario, so as to narrow the protection scope of the present invention.

[0032] For those skilled in the art, the present invention can be implemented without some of these specific details. The following description of the embodiments is only to provide a better understanding of the present invention by showing examples of the present invention.

[0033] Figure 1 is a sectional view of a valve structure for purge switching of a rocket engine according to an embodiment of the present invention; Figure 2 is a schematic diagram of a traditional rocket engine propellant purge system; Figure 3 is a sectional view of the valve structure during ground purge according to an embodiment of the present invention; Figure 4 is a sectional view of the valve structure during in-flight purge according to an embodiment of the present invention; Figure 5 is a schematic diagram of a rocket engine propellant purge system according to an embodiment of the present invention; Figure 6 is Figure 1 a sectional view taken along the A-A direction in Figure 7 is Figure 1 an enlarged view of B in

[0034] As Figure 1As shown in the figure, the present invention provides a valve structure for rocket engine purge switching, including: a housing 1, a sleeve 5 and a valve cover 4. The housing 1 is fixedly connected to the sleeve 5 to form a first cavity 10. The housing 1 is provided with an on-board purge inlet 11 that communicates the first cavity 10 with the on-board purge system along its axial direction, for introducing the gas of the on-board purge system into the first cavity 10. A first valve core 2 is arranged in the first cavity 10, and the first valve core 2 is in clearance fit with the first cavity 10. A first elastic element 3 is arranged between the first valve core 2 and the sleeve 5, and the first valve core 2 abuts against the on-board purge inlet 11 under the elastic action of the first elastic element 3 to seal the on-board purge inlet 11. The sleeve 5 is fixedly connected to the valve cover 4 to form a second cavity, and the valve cover 4 is provided with a ground purge inlet 12 that communicates the second cavity with the ground purge system, for introducing the gas of the ground purge system into the second cavity. The sleeve 5 is provided with a first purge hole 13 that communicates the first cavity 10 and the second cavity. A second valve core 7 is arranged in the second cavity, and the second valve core 7 is in clearance fit with the second cavity. A second elastic element 8 is arranged between the second valve core 7 and the sleeve 5, and the second valve core 7 abuts against the ground purge inlet 12 under the elastic action of the second elastic element 8 to seal the ground purge inlet 12. The housing 1 is further provided with a purge outlet 14 that communicates the first cavity 10 and the rocket engine, for discharging the gas in the first cavity 10 to the rocket engine. When the on-board purge system ventilates the on-board purge inlet 11, the gas acts on the first valve core 2, causing it to move in a direction away from the on-board purge inlet 11 to open the on-board purge inlet 11. The gas enters the first cavity 10 and flows out from the purge outlet 14 to the rocket engine to purge the rocket engine. When the ground purge system ventilates the ground purge inlet 12, the gas acts on the second valve core 7, causing it to move in a direction away from the ground purge inlet 12 to open the ground purge inlet 12. The gas enters the second cavity, enters the first cavity 10 from the first purge hole 13 and flows out from the purge outlet 14 to the rocket engine to purge the rocket engine.

[0035] Specifically, usually before the launch of a space vehicle, the ground purge system provides the gas source to perform the ground purge work on the oxidizer pipeline and the fuel pipeline. Just before the rocket is launched, the ground purge is switched to the on-board gas cylinder to perform the on-board purge on the engine. As Figure 2 shown, the rocket engine propellant purge system (including the ground purge system and the on-board purge system) usually requires four purge check valves 23 as control elements to complete the switching of ground-to-airframe purge. The large number of check valves makes the rocket structure, component layout, etc. more complex.

[0036] In this embodiment, after the valve structure is assembled, the housing and the sleeve cooperate to form the on-board purge path, and the sleeve and the valve cover cooperate to form the ground purge path. Both ends of the first elastic element respectively abut against the opposite end faces of the first valve core and the sleeve. In the initial state (such as Figure 1As shown in the figure, under the elastic action of the first elastic element, the first valve core abuts against the upper blowing removal inlet of the housing, and the upper blowing removal inlet is in a closed state. That is, the upper blowing removal inlet and the blowing removal outlet are closed and not connected to each other. At the same time, under the elastic action of the second elastic element, the second valve core abuts against the ground blowing removal inlet of the valve cover, and the ground blowing removal inlet is in a closed state. That is, the ground blowing removal inlet and the blowing removal outlet are closed and not connected to each other. As Figure 3 shown, when the ground blowing removal system supplies gas source to the ground blowing removal inlet, the medium force generated by the ground blowing removal gas overcomes the elastic force of the second elastic element, causing the second valve core to move away from the ground blowing removal inlet in a direction away from the valve cover, and the ground blowing removal inlet is opened and connected to the blowing removal outlet. At this time, the ground blowing removal gas enters the second cavity through the ground blowing removal inlet, enters the first cavity through the first blowing removal hole, and finally flows out from the blowing removal outlet to the rocket engine system for ground blowing removal work. When approaching the takeoff of the space vehicle, the gas source of the ground blowing removal system is closed and disconnected from the space vehicle, and it is switched to the upper blowing removal work (as Figure 4 shown), and the upper blowing removal system starts to supply gas source to the upper blowing removal inlet. At this time, the second valve core is reset under the elastic force of the second elastic element and presses tightly on the ground blowing removal inlet, that is, the ground blowing removal inlet is closed. The medium force generated by the upper blowing removal gas overcomes the elastic force of the first elastic element, causing the first valve core to move away from the housing in a direction away from the upper blowing removal inlet, and the upper blowing removal inlet is opened and connected to the blowing removal outlet. At this time, the upper blowing removal gas enters the first cavity through the upper blowing removal inlet and flows out from the blowing removal outlet to the rocket engine system for upper blowing removal work. During the flight of the space vehicle, the gas source of the upper blowing removal system is closed, and the first elastic element pushes the first valve core to reset and provides the sealing force between the first valve core and the housing, causing the first valve core to press tightly on the upper blowing removal inlet to keep it in a closed state. At the same time, the second valve core presses tightly on the ground blowing removal inlet under the elastic force of the second elastic element to keep it in a closed state. Since both the upper blowing removal path and the ground blowing removal path of the valve structure are one-way valve structures, even if the cryogenic high-pressure propellant medium downstream of the blowing removal outlet flows back to the first cavity and / or the second cavity through the blowing removal outlet, the cryogenic propellant does not flow back to the upstream of the blowing removal path (i.e., the upstream of the valve structure), so it will not affect the upstream of the blowing removal path.

[0037] The valve structure provided in this embodiment is a normally closed combined structure, which has a simple structure and reliable operation. As Figure 5 shown, one valve structure is used for oxygen path blowing removal, and one valve structure is used for fuel path blowing removal. That is, only two valve structures provided in this embodiment need to be applied to the blowing removal system to realize the switching function of the upper blowing removal path and the ground blowing removal path blowing removal system, simplify the structure of the engine blowing removal system, and thus simplify the structure of the engine system.

[0038] According to an embodiment of the present invention, the blowing removal outlet 14 can be arranged on the circumferential side wall of the housing.

[0039] Further, the purge outlet 14 can be arranged in the radial direction of the circumferential side wall of the housing.

[0040] According to an embodiment of the present invention, the first elastic element and the second elastic element can be spring structures. The first valve core can reciprocate in the first cavity along its axial direction to open or close the purge inlet on the arrow. The second valve core can reciprocate in the second cavity along its axial direction to open or close the ground purge inlet.

[0041] As Figure 6 shown, according to an embodiment of the present invention, the first valve core 2 is provided with an inclined cutting surface 15 in its circumferential direction. The circumferential surface of the first valve core 2 fits against the inner wall of the housing 1 and can slide relative thereto to perform circumferential limiting on the first valve core 2. The inclined cutting surface 15 of the first valve core 2 and the inner wall of the housing 1 form a flat gap for gas to flow in the first cavity 10 when the first valve core 2 is away from the purge inlet 11 on the arrow.

[0042] In this embodiment, the outer circle of the first valve core can be provided with a plurality of inclined cutting surfaces in its circumferential direction. The inclined cutting surfaces and the inner wall of the housing form a flat void structure, which can enable the purge gas on the arrow to flow through the purge inlet on the arrow, along the flat void structure channel in the first cavity, and flow to the purge outlet.

[0043] As Figure 1 shown, according to an embodiment of the present invention, a first non-metallic sealing surface 16 is provided on the opposite surface of the first valve core 2 and the housing 1 at the purge inlet 11 on the arrow for sealing between the first valve core 2 and the purge inlet 11 when the first valve core 2 abuts against the purge inlet 11 on the arrow.

[0044] In this embodiment, correspondingly, the inner wall of the housing in the circumferential direction of the purge inlet on the arrow (i.e., the surface opposite to the first valve core) is provided with a first metal sealing surface that cooperates with the first non-metallic sealing surface to form a first sealing pair.

[0045] According to an embodiment of the present invention, a second non-metallic sealing surface 17 is provided on the opposite surface of the first valve core 2 and the sleeve 5 at the first purge hole 13 for sealing between the first valve core 2 and the first purge hole 13 when the first valve core 2 abuts against the first purge hole 13.

[0046] In this embodiment, correspondingly, the sleeve at the inlet of the first purge hole is provided with a second metal sealing surface that cooperates with the second non-metallic sealing surface on the surface opposite to the first valve core to form a second sealing pair. The connection relationship between the first valve core and the first non-metallic sealing surface and the second non-metallic sealing surface can be in the form of inlay, and the present invention does not specifically limit it.

[0047] According to an embodiment of the present invention, the valve cover 4 includes a guide sleeve 6 fixedly arranged circumferentially along its inner wall, and the guide sleeve 6 is provided with a guide hole 18. The guide hole 18 is used to place the second valve core 7 for circumferential limitation thereof. The second valve core 7 is of a T-shaped structure. The guide sleeve 6 is provided with a second purge hole 19 communicating the ground purge inlet 12 and the second cavity along its circumferential direction. The second valve core 7 moves axially along the guide hole 18 to open or close the second purge hole 19.

[0048] In this embodiment, the guide sleeve is fixedly arranged in the second cavity. The guide hole can be a hole-shaped channel, and the long rod portion of the T-shaped structure of the second valve core passes through the guide hole, enabling the long rod portion of the second valve core to reciprocate axially along the guide hole without deviating from the central axis of the valve structure. The second purge hole can be a hole-shaped channel through which the purge medium (i.e., the ground purge gas) can flow.

[0049] According to an embodiment of the present invention, the guide sleeve 6 is provided with a plurality of second purge holes 19 along its circumferential direction.

[0050] As Figure 7 shown, according to an embodiment of the present invention, the sleeve 5 includes a base 9 fixedly arranged circumferentially along its inner wall, and the base 9 divides the second cavity into a first sub-cavity 20 and a second sub-cavity 21 along its axial direction. The second elastic element 8 is arranged between the second valve core 7 and the base 9. The base 9 is provided with a third purge hole 22 along its circumferential direction for communicating the first sub-cavity 20 and the second sub-cavity 21. When the ground purge system ventilates the ground purge inlet 12, the second valve core 7 moves towards the base 9, and the gas enters the second sub-cavity 21 from the ground purge inlet 12 through the second purge hole 19, then enters the first sub-cavity 20 through the third purge hole 22, and enters the first cavity 10 from the first sub-cavity 20 through the first purge hole 13, and then flows out from the purge outlet 14.

[0051] In this embodiment, after the valve structure is assembled, the components in the second cavity formed by the sleeve and the valve cover form a one-way valve structure of the ground purge path, including a guide sleeve, a second valve core, a second elastic element, and a base. At this time, both ends of the second elastic element respectively abut against the opposite end faces of the base and the second valve core, and the second valve core abuts against the guide sleeve under the elastic force of the second elastic element, closing the second purge hole, that is, the ground purge path is in a closed state. When the ground purge system ventilates the ground purge inlet, the second valve core moves towards the base (i.e., away from the guide sleeve), the second purge hole opens and is connected to the third purge hole, that is, the one-way valve structure of the ground purge path is in an open state.

[0052] According to an embodiment of the present invention, the base 9 is provided with a plurality of third purge holes 22 along its circumferential direction. When the second valve core 7 abuts against the base, the third purge holes 22 are avoided.

[0053] In this embodiment, the base is fixedly arranged in the second cavity. The third purge hole can be a hole-shaped channel for the circulation of the purge medium (i.e., the ground purge gas).

[0054] According to an embodiment of the present invention, a third non-metallic sealing surface is arranged at the mating position of the second spool 7 and the guide sleeve 6 for sealing between the two.

[0055] In this embodiment, correspondingly, a third metallic sealing surface that mates with the third non-metallic sealing surface is arranged on the opposite surface of the guide sleeve and the second spool, forming a third sealing pair with the third non-metallic sealing surface, capable of realizing the on-off function between the ground purge inlet and the purge outlet. When the ground purge system ventilates the ground purge inlet, the second spool moves in the direction of the base (i.e., away from the guide sleeve) away from the third metallic sealing surface of the guide sleeve, the second purge hole opens and communicates with the third purge hole. The ground purge gas passes through the ground purge inlet, the second purge hole, the third purge hole, and the first purge hole, and finally flows out through the purge outlet to the rocket engine system. As Figure 3 shown, when the ground purge system ventilates the ground purge inlet, the second spool can move left until it fits against the mating end surface of the base, or it can maintain a certain distance from it.

[0056] When approaching rocket takeoff, the ground purge path is disconnected from the ground purge system, and the second elastic element pushes the second spool to reset and provides the sealing force between the second spool and the guide sleeve, causing the second spool to press against the third metallic sealing surface of the guide sleeve. At this time, the check valve structure of the ground purge path closes, and the valve structure switches to the on-board purge mode, and the on-board purge system provides the gas source to the on-board purge inlet. The medium force generated by the on-board purge gas overcomes the elastic force of the first elastic element, causing the first spool to move right away from the first metallic sealing surface of the housing, and the on-board purge inlet opens. As Figure 4 shown, when the on-board purge system ventilates the on-board purge inlet, the first spool can move right until it fits against the mating end surface (i.e., the second metallic sealing surface) of the sleeve, or it can maintain a certain distance from it. When the first spool fits against the second metallic sealing surface of the sleeve, the second non-metallic sealing surface arranged on the right end surface of the first spool forms a seal with the sleeve.

[0057] On the other hand, the present invention provides a rocket including the above valve structure.

[0058] The above embodiments of the present invention can be combined with each other and have corresponding technical effects.

[0059] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A valve structure for rocket engine purge switching, characterized in that, Comprising: A housing, a sleeve and a valve cover; The housing is fixedly connected to the sleeve to form a first cavity; The housing is provided with an on-arrow purge inlet communicating the first cavity and the on-arrow purge system in its axial direction for introducing the gas of the on-arrow purge system into the first cavity; a first valve core is arranged in the first cavity, and the first valve core is in clearance fit with the first cavity; a first elastic element is arranged between the first valve core and the sleeve, and the first valve core abuts against the on-arrow purge inlet under the elastic action of the first elastic element to seal the on-arrow purge inlet; The sleeve is fixedly connected to the valve cover to form a second cavity, and the valve cover is provided with a ground purge inlet communicating the second cavity and the ground purge system for introducing the gas of the ground purge system into the second cavity; the sleeve is provided with a first purge hole communicating the first cavity and the second cavity; a second valve core is arranged in the second cavity, the second valve core is in clearance fit with the second cavity, a second elastic element is arranged between the second valve core and the sleeve, and the second valve core abuts against the ground purge inlet under the elastic action of the second elastic element to seal the ground purge inlet; The housing is further provided with a purge outlet communicating the first cavity and the rocket engine for discharging the gas in the first cavity to the rocket engine; When the on-arrow purge system ventilates the on-arrow purge inlet, the gas acts on the first valve core, causing it to move in a direction away from the on-arrow purge inlet to open the on-arrow purge inlet. The gas enters the first cavity and flows out from the purge outlet to the rocket engine to purge the rocket engine; when the ground purge system ventilates the ground purge inlet, the gas acts on the second valve core, causing it to move in a direction away from the ground purge inlet to open the ground purge inlet. The gas enters the second cavity, enters the first cavity through the first purge hole and flows out from the purge outlet to the rocket engine to purge the rocket engine.

2. The valve structure according to claim 1, characterized in that, The first valve core is provided with an inclined plane on its circumferential direction; the circumferential surface of the first valve core fits against the inner wall of the housing and can slide relative to it to perform circumferential limit on the first valve core; the inclined plane of the first valve core and the inner wall of the housing form a flat gap for the gas to flow in the first cavity when the first valve core is away from the on-arrow purge inlet.

3. The valve structure according to claim 1, characterized in that, A first non-metallic sealing surface is arranged on the relative surface of the first valve core and the housing at the on-arrow purge inlet for sealing between the first valve core and the on-arrow purge inlet when the first valve core abuts against the on-arrow purge inlet.

4. The valve structure according to claim 1, characterized in that, A second non-metallic sealing surface is arranged on the relative surface of the first valve core and the sleeve at the first purge hole for sealing between the first valve core and the first purge hole when the first valve core abuts against the first purge hole.

5. The valve structure according to claim 1, characterized in that, The valve cover includes a guide sleeve fixedly arranged circumferentially along its inner wall, and the guide sleeve is provided with a guide hole; the guide hole is used to place the second valve core to circumferentially limit it; the second valve core is of a T-shaped structure; the guide sleeve is provided with a second purge hole communicating the ground purge inlet and the second cavity along its circumferential direction, and the second valve core moves axially along the guide hole to open or close the second purge hole.

6. The valve structure according to claim 5, characterized in that, The guide sleeve is provided with a plurality of the second purge holes along its circumferential direction.

7. The valve structure according to claim 6, characterized in that, The sleeve includes a base fixedly arranged circumferentially along its inner wall, and the base divides the second cavity into a first sub-cavity and a second sub-cavity along its axial direction; the second elastic element is arranged between the second valve core and the base; the base is provided with a third purge hole along its circumferential direction for communicating the first sub-cavity and the second sub-cavity; When the ground purge system ventilates the ground purge inlet, the second valve core moves towards the base, and the gas enters the second sub-cavity from the ground purge inlet through the second purge hole, then enters the first sub-cavity through the third purge hole, and enters the first cavity from the first sub-cavity through the first purge hole, and then flows out from the purge outlet.

8. The valve structure according to claim 7, characterized in that, The base is provided with a plurality of the third purge holes along its circumferential direction; when the second valve core abuts against the base, the third purge holes are avoided.

9. The valve structure according to claim 5, characterized in that, A third non-metallic sealing surface is arranged at the matching position of the second valve core and the guide sleeve for sealing between the two.

10. A rocket, characterized in that, It includes the valve structure according to any one of claims 1-9.

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