A single-degree-of-freedom bellows equivalent device

Abstract

The present invention discloses a single-degree-of-freedom bellows equivalent device, which relates to the field of aerospace technology and is used to solve the problems of inaccurate bending stiffness of the bellows simulated by the bellows simulator and inflexible stiffness in a single bending direction. The bellows simulation device includes: a bellows simulator, a first mounting structure, and a second mounting structure. The bellows simulator has a first end face and a second end face. The first mounting structure is provided on the first end face and is used to connect to the frame of the engine. The second mounting structure is provided on the second end face and is used to connect to the nozzle of the engine. The bellows simulation device also includes: a swing mechanism, and the first mounting structure and the second mounting structure are connected by the swing mechanism. The bellows simulation device provided by the present invention is used in aerospace experiments.

Description

Technical Field

[0001] The present invention relates to the field of aerospace technology, and in particular to a single-degree-of-freedom bellows equivalent device. Background Art

[0002] During rocket flight, the servo mechanism is subjected to elastic moment loads generated by the bending deformation of the engine bellows. When testing the servo mechanism's performance under experimental conditions, it is necessary to simulate the elastic moment load generated by the bellows. The elastic moment load on the bellows during flight depends not only on the bellows' structure but also on the fuel pressure and temperature within the bellows.

[0003] In the prior art, the simulated bellows device uses two springs symmetrically arranged on both sides of the engine swing axis to simulate the bellows. When the engine swings, one side of the spring is stretched and the other side is compressed. Since the bending stiffness of the spring is inconsistent in the circumferential direction, the bending stiffness of the simulated bellows is inaccurate. Currently, the means of changing the stiffness of the elastic structure of the bellows are limited to the following technical means: changing the material, changing the pitch, and changing the wire diameter or the mean diameter. As a result, the stiffness of the bellows in a single bending direction is not flexible. Summary of the Invention

[0004] The object of the present invention is to provide a single-degree-of-freedom bellows equivalent device to solve the problems of inaccurate bending stiffness of the bellows simulated by a bellows simulator and inflexible stiffness in a single bending direction.

[0005] In a first aspect, the present invention provides a single-degree-of-freedom bellows equivalent device comprising: a bellows simulating member, a first mounting structure, and a second mounting structure, wherein the bellows simulating member has a first end face and a second end face opposite to each other, the first mounting structure being disposed on the first end face and configured to be connected to a frame of an engine, and the second mounting structure being disposed on the second end face and configured to be connected to a nozzle of the engine;

[0006] The bellows simulation device also includes: a swinging mechanism, the first mounting structure and the second mounting structure are connected by a swinging mechanism, the bellows simulation has a plurality of through grooves distributed along the distribution direction from the first end face to the second end face, each through groove extends along the circumferential direction of the bellows simulation, the groove depth direction of each through groove is consistent with the radial direction of the bellows simulation, and the groove opening directions of two adjacent through grooves are different.

[0007] Compared with the prior art, in the bellows simulation device provided by the present invention, the bellows simulation part has a first end face and a second end face relative to each other, a first mounting structure part is provided on the first end face, the first mounting structure part is used to connect to the engine frame, a second mounting structure part is provided on the second end face, the second mounting structure part is used to connect to the engine nozzle, and the first mounting structure part and the second mounting structure part are connected by a swing mechanism. Based on this, when the engine nozzle starts to move, it can drive the second mounting structure part to move, and the movement of the second mounting structure part drives the second end face of the bellows simulation part to move, and the movement of the second end face will drive the entire bellows simulation part to move, and the first mounting structure part and the second mounting structure part are connected by a swing mechanism. When the bellows simulation part moves, the swing mechanism will swing synchronously with the bellows simulation part, and by ensuring that the bellows simulation part can accurately simulate the swing of the bellows, the bending stiffness of the bellows can be accurately obtained by measuring the bellows simulation part.

[0008] On this basis, the bellows simulation part has a plurality of through grooves distributed along the distribution direction from the first end face to the second end face, each through groove extending along the circumferential direction of the bellows simulation part, the groove depth direction of each through groove being the same as the radial direction of the bellows simulation part, and each through groove being distributed along the direction from the first end face to the second end face. When the bellows simulation part moves to simulate the motion state of the bellows, the bellows simulation part can simulate the elastic moment load generated by the bellows during motion. Moreover, since the notch directions of two adjacent through grooves are different, the bellows simulation part can bend along different notch directions, not just in the same direction. At the same time, by changing the extension direction and distribution direction of the through grooves, as well as changing the groove width, groove depth and spacing of the through grooves, the bellows simulation part can simulate the bending stiffness of the bellows. Therefore, the elastic moment load generated by the bellows during motion can be simulated without changing the material, pitch, wire diameter or mean diameter of the bellows simulation part, effectively solving the problem of the bellows simulation part having inflexible stiffness in a single bending direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0010] Figure 1 A structural diagram of a bellows simulation device according to an embodiment of the present invention is shown;

[0011] Figure 2 A structural diagram of a bellows simulation component according to an embodiment of the present invention is shown;

[0012] Figure 3 A front view of a bellows simulation member according to an embodiment of the present invention is shown;

[0013] Figure 4 A cross-sectional view showing a bellows simulation according to an embodiment of the present invention.

[0014] Reference numerals:

[0015] 101 - first mounting structure, 102 - second mounting structure, 103 - bellows simulation component, 104 - swing mechanism, 1041 - first connecting member, 1042 - swing shaft, 1043 - second connecting member, 201 - first end face, 202 - through groove, 203 - stress hole, 204 - second end face. DETAILED DESCRIPTION

[0016] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0017] It should be noted that when an element is referred to as being “fixed on” or “disposed on” another element, it may be directly on the other element or indirectly on the other element. When an element is referred to as being “connected to” another element, it may be directly connected to the other element or indirectly connected to the other element.

[0018] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined. "Several" means one or more, unless otherwise specifically defined.

[0019] In the description of the present invention, it should be understood that the terms "up", "down", "front", "back", "left", "right", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0020] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and may encompass internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0021] During flight, the servo mechanism's nozzle movement must overcome the elastic torque load generated by the bellows' bending and torsional deformation. When testing the servo mechanism's performance under experimental conditions, it's necessary to simulate the bellows' elastic torque load. The bellows' elastic torque load during flight depends not only on the bellows' structure but also on the fuel pressure and temperature within the bellows.

[0022] In the prior art, the simulated bellows device uses two springs symmetrically arranged on both sides of the engine swing axis to simulate the bellows. When the engine swings, one side of the spring is stretched and the other side is compressed. Since the bending stiffness of the spring is inconsistent in the circumferential direction, the bending stiffness of the simulated bellows is inaccurate. Currently, the means of changing the stiffness of the elastic structure of the bellows are limited to the following technical means: changing the material, changing the pitch, and changing the wire diameter or the mean diameter. As a result, the stiffness of the bellows in a single bending direction is not flexible.

[0023] In response to the above problems, an embodiment of the present invention provides a single-degree-of-freedom bellows equivalent device to solve the problems of inaccurate bending stiffness of the bellows simulated by the bellows simulator and inflexible stiffness in a single bending direction.

[0024] Figure 1 FIG. 1 shows a structural diagram of a bellows simulation device according to an embodiment of the present invention. Figure 1 As shown, the bellows simulation device provided by the exemplary embodiment of the present invention includes: a bellows simulation member 103, a first mounting structure member 101 and a second mounting structure member 102. The bellows simulation member 103 has a first end face and a second end face opposite to each other. The first mounting structure member 101 is provided on the first end face and is used to connect to the engine frame. The second mounting structure member 102 is provided on the second end face and is used to connect to the engine nozzle.

[0025] The bellows simulation device also includes: a swinging mechanism 104, the first mounting structure 101 and the second mounting structure 102 are connected by the swinging mechanism 104, the bellows simulation 103 has a plurality of through grooves distributed along the distribution direction from the first end face to the second end face, each through groove extends along the circumferential direction of the bellows simulation 103, the groove depth direction of each through groove is the same as the radial direction of the bellows simulation, and the groove opening directions of two adjacent through grooves are different.

[0026] When implementing it specifically, Figure 1 As shown, the bellows simulation device of an embodiment of the present invention is used to replace the bellows of the engine and its accessory structure, and the second mounting structure 102 is connected to the nozzle of the engine, and the first mounting structure 101 is connected to the frame of the engine, wherein the first mounting structure 101 and the second mounting structure 102 can be connected to the nozzle of the engine and the frame of the engine as flange structures.

[0027] Exemplarily, the flange connected to the nozzle of the engine is the lower flange, and the flange connected to the frame of the engine is the upper flange. The upper flange can be connected to the first mounting structure of the bellows simulation by bolts. The flange connected to the nozzle of the engine is the lower flange. The lower flange can be connected to the second mounting structure of the bellows simulation by bolts. On this basis, the first mounting structure and the second mounting structure are respectively connected to the swing mechanism. Therefore, the bellows simulation is located between the nozzle and the frame.

[0028] When the engine starts working, the engine drives the nozzle to swing, and the nozzle can drive the second end face of the bellows simulation to simulate the swing of the bellows. The swing of the second end face of the bellows simulation drives the entire bellows simulation to swing. At the same time, the first mounting structure and the second mounting structure are connected by a swinging mechanism. When the entire bellows simulation swings, the swinging mechanism is driven to start swinging, thereby ensuring that the bellows simulation can accurately simulate the swing of the bellows, and thus the bending stiffness, bending angle and elastic moment load of the bellows are accurately obtained by measuring the bellows simulation.

[0029] When testing the performance of a servo mechanism under experimental conditions, such as Figure 2 As shown, since the bellows simulation component 103 has a first end face 201 and a second end face 204 relative to each other, the first mounting structure component provided on the first end face 201 is used to connect with the engine frame. Therefore, the power provided by the engine nozzle is transmitted to the bellows simulation component 103, and the movement of the bellows simulation component 103 drives the engine frame to start swinging. The first mounting structure component provided on the first end face 201 and the second mounting structure component provided on the second end face are respectively connected to the bellows simulation component 103 through a swinging mechanism. Therefore, the bellows simulation component 103 starts to move to simulate the motion state of the bellows when it moves.

[0030] In order to simulate a bellows, the bellows simulation part can be an elastic bellows simulation part. In order to achieve the same effect as the bellows, the bellows simulation part can be provided with through grooves. There are multiple through grooves, each of which extends along the circumferential direction of the bellows simulation part. The groove depth direction of each through groove is the same as the radial direction of the bellows simulation part. Each through groove is distributed along the direction from the first end face to the second end face, and the groove opening directions of two adjacent through grooves are different.

[0031] It can be seen from the above specific implementation process that the bellows simulation has a plurality of through grooves distributed along the distribution direction from the first end face to the second end face, each through groove extends along the circumferential direction of the bellows simulation, and the groove depth direction of each through groove is the same as the radial direction of the bellows simulation. Each through groove is distributed along the direction from the first end face to the second end face. When the bellows simulation moves to simulate the motion state of the bellows, the bellows simulation can simulate the elastic moment load generated by the bellows during movement; moreover, since the slot directions of two adjacent through grooves are different, the bellows simulation can bend along different slot directions, and is not limited to bending in the same direction. At the same time, by changing the extension direction and distribution direction of the through grooves, as well as changing the slot width, slot depth and spacing of the through grooves, the bellows simulation can simulate the bending stiffness of the bellows. Therefore, it is only necessary to change the extension direction and distribution direction of the through groove, without changing the material, pitch, wire diameter or mean diameter of the bellows simulation part, to simulate the elastic moment load generated by the bellows during movement, effectively solving the problem of the inflexibility of the stiffness of the bellows simulation part in a single bending direction.

[0032] In one alternative, Figure 2 The structure diagram of the bellows simulation member according to the embodiment of the present invention is shown as follows: Figure 2 As shown, at least one end of each through slot 202 has a stress hole 203, the diameter of the stress hole 203 is larger than the slot width of the corresponding through slot 202, the slot width direction of the through slot 202 is the same as the distribution direction from the first end face to the second end face, and the axial direction of the stress hole 203 is perpendicular to the distribution direction from the first end face to the second end face. Here, it can be understood that the projection of the stress hole 203 on the bellows simulation part 103 is actually a circle divided by the through slot 202.

[0033] In practical applications, such as Figure 2As shown, in order to reduce the stress concentration at the starting point and the end point of the through slot 202, a stress hole 203 is opened at at least one end of each through slot 202. Here, the stress hole 203 of the through slot 202 can be set at the starting point, the stress hole 203 of the through slot 202 can also be set at the starting point and the end point, the stress hole 203 of the through slot 202 can be set at the end point, the aperture of the stress hole 203 is larger than the slot width of the through slot 202, the axial direction of the stress hole 203 is perpendicular to the slot depth direction of the corresponding through slot 202, and the slot width direction of the through slot 202 is the same as the distribution direction from the first end face 201 to the second end face 204, which will not only offset the stress generated by the bellows simulation during the movement, but also improve the service life of the bellows simulation.

[0034] In an alternative approach, Figure 2 As shown, the extension directions of two adjacent through slots 202 are parallel. Here, it should be understood that the extension direction of the through slots 202 is the circumferential direction mentioned above, and the spacing between two adjacent through slots 202 is the same, and the extension direction of each through slot 202 is parallel to the horizontal direction, thereby ensuring that the bending stiffness between each through slot 202 of the bellows simulator 103 is consistent, and ensuring that the bending angle and bending stiffness of the bellows obtained by the bellows simulator 103 when the movement of the bellows is simulated are more accurate.

[0035] For example, Figure 2 As shown, two adjacent through grooves 202 intersect in the cross-sectional projection of the bellows simulation part 103. At this time, it can be understood that the starting points of the two adjacent through grooves intersect with each other, or it can be understood that the end points of the two adjacent through grooves 202 intersect with each other, or it can be understood that the starting points and end points of the adjacent through grooves 202 intersect with each other. This will not only make the stress distribution of the simulated bellows in the axial direction more uniform, but also make the through grooves 202 consistent in the axial, circumferential and radial directions, thereby ensuring that the bellows module 103 is consistent in the axial, circumferential and radial directions, and making the bending stiffness of the bellows simulation part 103 consistent in the axial, circumferential and radial directions.

[0036] In one alternative, Figure 3 A front view of a bellows simulation member according to an embodiment of the present invention is shown. Figure 3 As shown, the plurality of through slots include at least two groups of through slots 202 , which are distributed along the distribution direction from the first end face to the second end face. Each group of through slots includes at least two types of through slots 202 , and the slot opening directions of two adjacent through slots 202 are different.

[0037] In practical applications, to ensure that the bellows simulator can flexibly simulate a bellows, multiple through-slots are provided on the bellows simulator. For example, by varying the spacing, width, and depth of the through-slots, the bending stiffness of the bellows under different operating conditions can be simulated. The multiple through-slots include at least two groups of through-slots, each of which is distributed along a direction from the first end face to the second end face. To ensure that the bellows simulator can accurately simulate the bellows, there are at least two groups of through-slots, each of which includes at least two types of through-slots, with the two types of through-slots having different opening directions.

[0038] For example, Figure 3 and Figure 4 As shown, the ends of the same through grooves in different groups of through grooves 202 overlap in cross-sectional projection on the bellows simulation. It should be understood that the same through grooves 202 in different groups of through grooves 202 may be two through grooves 202 with the same slot opening direction in two adjacent groups of through grooves. The cross-sectional projections of the through grooves with the same slot opening direction distributed along the direction from the first end face to the second end face overlap in cross-sectional projection on the bellows simulation. This ensures that the bending stiffness of the bellows simulation in the same direction is the same, and also fully utilizes the axial space of the simulated bellows, allowing the simulated bellows to have more through grooves, thereby increasing the simulation range of the simulated bellows.

[0039] In an alternative approach, Figure 1 As shown, the swing mechanism 104 includes a fixed structure and a swing shaft 1042 provided on the fixed structure, and the first mounting structure 101 and the second mounting structure 102 are connected through the fixed structure.

[0040] In actual application, the first mounting structure 101 and the second mounting structure 102 are connected by a swing mechanism 104. When the bellows simulation part 103 simulates the movement of the bellows, the nozzle can drive the second end face of the bellows simulation part 103 to simulate the swing of the bellows. At the same time, the nozzle can also drive the first end face of the bellows simulation part 103 to swing through the swing mechanism 104, thereby ensuring that the swing direction of the bellows simulation part 103 is consistent with that of the nozzle, and the bending of the entire bellows simulation device in a single direction can be realized.

[0041] For example, the bellows simulator body is a solid cylindrical structure, with the axial direction of the solid cylindrical structure extending from the first end face to the second end face. A bellows is actually an elastic member with a spring as its main structure. The bellows simulator is used to simulate a spring, so the bellows simulator is a solid cylindrical spring body. To more accurately simulate the bellows' motion, parameters such as bending stiffness, bending angle, and elastic moment load can be generated.

[0042] For example, Figure 1As shown, the fixing structure includes a first connecting member 1041 and a second connecting member 1043, the first connecting member 1041 is connected to the first mounting structure 101, and the second connecting member 1043 is connected to the second mounting structure 102. The end of the second connecting member 1043 facing away from the second mounting structure 102 has a groove, and the end of the first connecting member 1041 facing away from the first mounting structure is located in the groove, and the swing shaft passes through the groove and is rotatably connected to the end of the first connecting member 1041 facing away from the first mounting structure.

[0043] In practical applications, such as Figure 1 As shown, when the engine movement drives the swing mechanism to begin swinging, the swing mechanism 104 is a frame structure, and a swing shaft provided on the frame connects the first connecting member 1041 and the second connecting member 1043. As the engine drives the nozzle to move, the nozzle drives the bellows simulation member 103 to begin swinging. The swing mechanism 104 swings in the same direction as the bellows simulation member 103 as the bellows swings. The motion state of the swing mechanism 104 is the motion state generated by the bellows during movement. In order to make the swing mechanism 104 more flexible and swing in the same direction as the bellows simulation member 103, the end of the second connecting member 1043 facing away from the second mounting structure 102 has a groove. The end of the first connecting member 1041 facing away from the first mounting structure 101 is located in the groove. The swing shaft passes through the groove and is rotatably connected to the end of the first connecting member 1041 facing away from the first mounting structure 101.

[0044] Compared with the prior art, the swing mechanism provided by the present invention is used to simulate the motion state of a bellows simulation component during movement. When the bellows simulation component starts to move, the swing mechanism connected by the first connecting member and the second connecting member is subjected to tension or pressure in the same direction as the bellows simulation component. When the swing mechanism is subjected to tension or pressure in the same direction, the swing mechanism will swing in the same direction. When the swing mechanism starts to swing, the bellows simulation component is measured to accurately obtain the bending stiffness, bending angle and elastic moment load of the bellows.

[0045] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A single-degree-of-freedom bellows equivalent device, characterized in that: include: a bellows dummy, a first mounting structure, and a second mounting structure, wherein the bellows dummy has a first end face and a second end face opposite to each other, the first mounting structure being provided on the first end face and being connected to a frame of an engine, and the second mounting structure being provided on the second end face and being connected to a nozzle of the engine; The single-degree-of-freedom bellows equivalent device also includes: a swinging mechanism, the first mounting structure and the second mounting structure are connected by the swinging mechanism, the bellows simulation part has a plurality of through grooves distributed along the distribution direction from the first end face to the second end face, each of the through grooves extends along the circumferential direction of the bellows simulation part, the groove depth direction of each through groove is the same as the radial direction of the bellows simulation part, and the groove opening directions of two adjacent through grooves are different.

2. The single-degree-of-freedom bellows equivalent device according to claim 1, characterized in that: At least one end portion of each through slot has a stress hole.

3. The single-degree-of-freedom bellows equivalent device according to claim 2, characterized in that: The diameter of the stress hole is greater than the slot width of the corresponding through slot, the slot width direction of the through slot is the same as the distribution direction from the first end face to the second end face, and the axial direction of the stress hole is perpendicular to the distribution direction from the first end face to the second end face.

4. The single-degree-of-freedom bellows equivalent device according to claim 1, characterized in that: The extending directions of two adjacent through slots are parallel, and the extending direction of each through slot is parallel to the horizontal direction.

5. The single-degree-of-freedom bellows equivalent device according to claim 1, characterized in that: The distances between two adjacent through grooves are the same.

6. The single-degree-of-freedom bellows equivalent device according to claim 1, characterized in that: Two adjacent through grooves intersect in the cross-sectional projection of the bellows simulation component.

7. The single-degree-of-freedom bellows equivalent device according to claim 1, characterized in that: The plurality of through grooves include at least two groups of through grooves, and the at least two groups of through grooves are distributed along the distribution direction from the first end surface to the second end surface. Each group of through grooves includes at least two types of through grooves, and the groove opening directions of two adjacent through grooves are different.

8. The single-degree-of-freedom bellows equivalent device according to claim 7, characterized in that: The ends of the same through grooves in different groups of through grooves overlap in cross-sectional projection on the bellows simulation component.

9. The single-degree-of-freedom bellows equivalent device according to any one of claims 1 to 8, characterized in that: The swing mechanism includes a fixed structure and a swing shaft provided on the fixed structure, and the first mounting structure and the second mounting structure are connected through the swing mechanism.

10. The single-degree-of-freedom bellows equivalent device according to claim 9, characterized in that: The fixing structure includes a first connecting member and a second connecting member, the first connecting member is connected to the first mounting structure, the second connecting member is connected to the second mounting structure, the end of the second connecting member facing away from the second mounting structure has a groove, the end of the first connecting member facing away from the first mounting structure is located in the groove, and the swing shaft passes through the groove and is rotatably connected to the end of the first connecting member facing away from the first mounting.

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