A bellows elastic load equivalent device

Abstract

The application discloses a bellows elastic load equivalent device, and relates to the technical field of aerospace. The bellows elastic load equivalent device is used for simulating the real state of a bellows of an aircraft during flight, and achieving the problem of consistent bending stiffness of a bellows simulation part during ground testing. The bellows elastic load equivalent device comprises a bellows simulation part, the bellows simulation part has two opposite end faces, one of the two end faces is used for being connected with a frame of an engine, and the other end face is used for being connected with a nozzle of the engine. The bellows elastic load equivalent device further comprises a swing mechanism and two fixed connecting pieces. The bellows simulation part has a spiral groove which spirally extends along the distribution direction of the two end faces. The bellows elastic load equivalent device further comprises two mounting structures. The bellows elastic load equivalent device is used in aerospace experiments.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of ground test device, and particularly relates to a bellows elastic load equivalent device. BACKGROUND

[0002] During the flight of the aircraft, the servo mechanism needs to overcome the load of the elastic moment of the bellows due to bending and torsional deformation when pushing the nozzle to swing. When testing the performance of the servo mechanism under experimental conditions, the elastic moment load generated by the bellows needs to be simulated. The elastic moment load of the bellows of the aircraft during flight is not only related to the structure of the bellows, but also related to the fuel pressure and temperature in the bellows.

[0003] In the prior art, the simulation method of the deformation moment of the post-pump swing engine in the inflation state, in which two springs symmetrically arranged on both sides of the engine swing shaft are used to simulate the bellows, one side of the spring-simulated bellows is pulled and the other side is pressed when the engine swings. Due to the inconsistency of the bending stiffness of the spring in the circumferential direction, the elastic moment load simulated by this method has a large error. Secondly, the symmetrical device causes stress concentration at the root of the spring during use, which not only affects the service life of the spring but also makes the bending angle range of the spring smaller. Therefore, how to design a bellows elastic load equivalent device that can simulate the real state of the bellows during the flight of the aircraft is particularly important for the load test of the servo mechanism. SUMMARY

[0004] The purpose of the present application is to provide a bellows elastic load equivalent device to simulate the real state of the bellows of the aircraft during flight and to realize the problem of consistent bending stiffness of the bellows simulation part during ground test.

[0005] In the first aspect, the present application provides a bellows elastic load equivalent device, comprising: a bellows simulation part, the bellows simulation part having two opposite end faces, one of the two end faces being used for connecting with the frame of the engine, and the other end face being used for connecting with the nozzle of the engine, the bellows elastic load equivalent device further comprising a swing mechanism and two fixed connecting pieces, the swing mechanism being connected with the two fixed connecting pieces respectively, each fixed connecting piece being arranged at the corresponding end face, the bellows simulation part having a spiral groove extending along the distribution direction of the two end faces, and the bellows elastic load equivalent device further comprising two mounting structures, each mounting structure being arranged at the corresponding end face.

[0006] Compared with the prior art, the bellows elastic load equivalent device provided by the application comprises a bellows simulation piece, the bellows simulation piece has two opposite end faces, one of the two end faces is connected with the frame of the engine through one of the mounting structures, the other end face is connected with the nozzle of the engine through the other mounting structure, when the bellows simulation piece is connected with the nozzle of the engine, the nozzle of the engine drives the bellows simulation piece to simulate the motion state of the bellows, and the bellows simulation piece generates an elastic moment load in the motion process, if the elastic moment load is excessively concentrated, the service life of the bellows is affected, on this basis, one of the end faces of the bellows simulation piece is connected with the mounting structure through a fixed connecting piece, the end face away from the end face is rotatably connected with the swing mechanism through the fixed connecting piece, the other end face is connected with the mounting structure through a fixed connecting piece, and the end face away from the other end face is rotatably connected with the swing mechanism through the fixed connecting piece. Based on this, when the bellows simulation piece simulates the motion of the bellows, the bellows simulation piece can simulate the elastic moment load generated by the bellows in the motion, and in order to more accurately simulate the elastic moment load generated by the bellows in the motion, a helical groove extending in a helical manner is arranged on the bellows simulation piece along the distribution direction of the two end faces, so that the actual elastic moment load of the simulated bellows is more accurate. The entire bellows simulation piece is arranged as a whole, so that the bending angle of the bellows simulation piece in the motion reaches a preset parameter, and the bellows simulation piece does not have the problems of one spring being compressed and one spring being stretched in the prior art, and the bending stiffness of the two springs is inconsistent due to the differences in structure and properties of the two springs, so that the elastic moment load error is large. The bellows simulation piece overcomes the problem of large elastic moment load error caused by the inconsistent bending stiffness of the spring in the circumferential direction in the prior art. BRIEF DESCRIPTION OF DRAWINGS

[0007] The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the application. In the drawings:

[0008] Figure 1 A schematic view of a spring group simulating a bellows in the prior art;

[0009] Figure 2 A structural view of the bellows elastic load equivalent device in the embodiment of the application;

[0010] Figure 3 A structural view of the bellows simulation piece in the embodiment of the application;

[0011] Figure 4 A sectional view of the bellows elastic load equivalent device in the embodiment of the application.

[0012] Reference signs:

[0013] 101 - first spring simulation piece, 102 - second spring simulation piece, 201 - mounting structure, 202 - first mounting piece, 203 - second mounting piece, 204 - first direction swing shaft, 205 - second direction swing shaft, 2051 - rotating bearing, 2052 - shaft sleeve, 206 - swing mechanism, 207 - bellows simulation piece, 2071 - through hole, 2072 - stress hole, 2073 - helical groove, 208 - fixing connecting piece, 209 - containing groove. DETAILED DESCRIPTION

[0014] In order to make the technical problems to be solved by the present application, technical solutions and beneficial effects clearer, the present application will be further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not used to limit the present application.

[0015] It should be noted that when an element is referred to as being "fixed" or "disposed" on another element, it can 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 can be directly connected to the other element or indirectly connected to the other element.

[0016] In addition, the terms "first", "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly and specifically limited. The meaning of "several" is one or more, unless otherwise explicitly and specifically limited.

[0017] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right" and the like indicate the orientation or positional relationship shown in the drawings, and are only used for the purpose of facilitating the description of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0018] In the description of the present application, it should be noted that unless otherwise expressly specified and limited, the terms "mounting", "connection", "linking" should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integrally connected, it can be mechanical connection, or electrical connection, it can be directly connected, or indirectly connected through intermediate medium, it can be internal communication of two elements or interaction relationship of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0019] During the flight of the aircraft, the servo mechanism needs to overcome the load of the elastic moment of the bellows due to the bending and torsional deformation when pushing the nozzle to swing. When testing the performance of the servo mechanism under experimental conditions, it is necessary to simulate the elastic moment load of the bellows. The elastic moment load of the bellows of the aircraft during flight is not only related to the structure of the bellows, but also related to the fuel pressure and temperature in the bellows.

[0020] In the prior art, the simulation method of the deformation moment of the post-pump swing engine in the inflation state is disclosed, in which two springs symmetrically arranged on both sides of the engine swing shaft are used to simulate the bellows. When the engine swings, one side of the spring-simulated bellows is subjected to tension and the other side is subjected to pressure. Due to the inconsistency of the bending stiffness of the spring in the circumferential direction, the simulation method has a large error in the elastic moment load. Secondly, the symmetrical device causes stress concentration at the root of the spring during use, which not only affects the service life of the spring but also makes the bending angle range of the spring smaller. Therefore, how to design an equivalent device for the elastic load of the bellows to simulate the equivalent state of the bellows during the flight of the aircraft is particularly important for the load test of the servo mechanism.

[0021] Figure 1 A customized spring group simulation bellows schematic diagram in the prior art is disclosed, as shown in Figure 1 Two springs symmetrically arranged on both sides of the engine swing shaft are used to simulate the bellows. When the engine swings, one side of the first spring simulation piece 101 of the spring is subjected to tension and the other side of the second spring simulation piece 102 is subjected to pressure, which is basically equivalent to the state of the bellows. Each spring satisfies: the rigidity height is equal to the height of the bellows; the outer edge size diameter is less than half the width of the bellows; the stroke is greater than the deformation moment of the spring when the engine swings to simulate the deformation moment of the bellows.

[0022] In view of the above problems, the embodiment of the present application provides a bellows elastic load equivalent device, which is used to simulate the real state of the bellows of the aircraft during flight, and realizes the problem of consistent bending stiffness of the bellows simulation piece during ground test.

[0023] Figure 2A structural diagram of the bellows elastic load equivalent device of the exemplary embodiment of the present application is shown. As shown in Figure 2 The bellows elastic load equivalent device provided by the exemplary embodiment of the present application comprises a bellows simulation piece 207 having two opposite end faces, one of which is used to connect with the frame of the engine, and the other is used to connect with the nozzle of the engine, and further comprises a swing mechanism 206 and two fixed connecting pieces 208, the swing mechanism 206 is connected with the two fixed connecting pieces 208 respectively, each fixed connecting piece 208 is arranged at the corresponding end face, and the bellows simulation piece has a helical groove extending along the distribution direction of the two end faces. The bellows elastic load equivalent device can further comprise two mounting structures 201, each mounting structure 201 is arranged at the corresponding end face, the mounting structure 201 can be a flange structure, the top of the flange is provided with a disc-shaped protruding structure, a plurality of bolt holes are arranged on the disc-shaped protruding structure in a staggered manner, which facilitates the connection with the nozzle structure and the like of the engine, and the two side edges are symmetrically provided with protruding structures for mounting the fixed connecting pieces, the fixed connecting piece is fixedly connected with the upper flange by a bolt and is arranged vertically downward, and the fixed connecting piece is fixedly connected with the lower flange by a bolt and is arranged vertically upward.

[0024] In specific implementation, as shown in Figure 2 The bellows elastic load equivalent device of the embodiment of the present application is used to replace the bellows and the accessory structure of the engine, and the flange as one mounting structure of the bellows elastic load equivalent device is connected with the nozzle of the engine, and the flange as the other mounting structure is connected with the frame of the engine, and the middle lines of the length directions of the above flanges are arranged perpendicular to each other.

[0025] The flange connected with the nozzle of the engine is the lower flange, and the flange connected with the frame of the engine is the upper flange, the upper flange can be connected with the first mounting piece of the bellows simulation piece by the fixed connecting piece through a bolt and is arranged vertically downward, the flange connected with the nozzle of the engine is the lower flange, and the lower flange can be connected with the second mounting piece of the bellows simulation piece by the fixed connecting piece through a bolt and is arranged vertically upward, and on this basis, the other end of the fixed connecting piece is connected with the swing mechanism respectively, and thus the bellows simulation piece is located between the nozzle and the frame.

[0026] When the engine starts to work, the nozzle can drive the bellows simulation piece to simulate the swing of the bellows through the swing of one end face of the bellows simulation piece, and the nozzle can also drive the swing mechanism to swing through the fixed connecting piece, and the swing mechanism can drive the other end face of the bellows simulation piece to swing through the fixed connecting piece, so as to ensure that the bellows simulation piece can accurately simulate the swing of the bellows, and thus the bending stiffness, the bending angle and the elastic moment load of the bellows can be accurately obtained by measuring the bellows simulation piece.

[0027] When testing the performance of the servo mechanism under experimental conditions, as shown in Figure 2 The power provided by the nozzle of the engine is transmitted to the bellows simulation member 207, and the bellows simulation member moves to make the frame of the engine start to swing. The swing mechanism 206 is connected with the bellows simulation member 207 through the fixed connecting members 208, and thus the bellows simulation member 207 starts to move to simulate the movement state of the bellows when the bellows moves. For example, the bellows simulation member can control the swing mechanism to swing along the X direction or the Y direction, respectively, and the bellows simulation member can simulate the bending deformation of the bellows when the bellows moves, and generate a bending and torsional moment load. On this basis, the performance test of the servo mechanism and other tests can be better performed.

[0028] As can be seen from the above specific implementation process, the bellows simulation member has helical grooves extending along the distribution direction of the two end faces. The movement state of the bellows simulation member is equivalent to the real state of the bellows when the bellows moves. In this way, the entire bellows simulation member is arranged as a whole, and the bending angle of the bellows simulation member is increased. At this time, the bellows simulation member can overcome the problem that the elastic moment load error is relatively large due to the inconsistency of the bending stiffness of the spring in the circumferential direction in the prior art. When the bellows simulation member starts to move with the nozzle, the two fixed connecting members are arranged perpendicularly to each other due to the perpendicular arrangement of the center lines of the flanges in the length direction. The swing of the bellows simulation member in the perpendicular direction is consistent, and the bending stiffness of the bellows simulation member in the perpendicular direction is consistent. At the same time, one end of the bellows simulation member is connected with the nozzle through the lower flange, and the other end of the bellows simulation member is connected with the frame through the upper flange. The bellows simulation member located between the nozzle and the frame can simulate the elastic moment load generated by the bellows through the swing mechanism. When there is no external force interference, the elastic moment load of the bellows simulation member can reach the preset parameters, so that the simulation of the elastic moment load of the bellows simulation member is more accurate, and the experimental effect obtained by the simulation is more reliable.

[0029] In an optional manner, the number of helical grooves is multiple, the pitches of the helical grooves are the same, and the multiple helical grooves are distributed along the distribution direction of the two end faces.

[0030] In actual application, as Figure 3As shown, in order to simulate a bellows, the bellows simulation part 207 can be an elastic bellows simulation part. In order to achieve the same effect as the bellows, a spiral groove 2073 can be opened in the bellows simulation part. There are multiple spiral grooves 2073 opened, and the pitch of each spiral groove is the same, and the multiple spiral grooves are distributed along the distribution direction of the two end faces.

[0031] In order to make the bellows simulator simulate the movement state of the bellows more accurately, the bellows simulator can be an elastic bellows simulator. In order to simulate the bending angle of the bellows during movement, a spiral groove can be provided in the bellows simulator. The same pitch of each spiral groove can ensure that the bending stiffness between each spiral groove of the bellows simulator is consistent. There can be multiple spiral grooves provided, which will ensure that the bellows simulator obtains the bending angle and bending stiffness of the bellows more accurately when simulating the movement of the bellows.

[0032] For example, Figure 3 As shown, when the pitches of the spiral grooves 2073 are the same, the endpoint of one spiral groove 2073 and the starting point of the other spiral groove in two adjacent spiral grooves are coplanar. In this case, the axial space of the simulated bellows can be fully utilized, resulting in more spiral grooves on the simulated bellows, thereby increasing the simulation range of the simulated bellows.

[0033] For example, in the orthographic projection of one end surface of the plurality of spiral grooves, the end projections of the plurality of spiral grooves are evenly distributed along the annular trajectory, thereby ensuring that the stress distribution of the simulated bellows in the axial direction is relatively uniform.

[0034] It can be seen that this will make the spiral groove bear consistent forces in the axial, circumferential and radial directions, thereby ensuring that the bellows module bears consistent forces in the axial, circumferential and radial directions, and making the bending stiffness of the bellows simulation component consistent in the axial, circumferential and radial directions.

[0035] For example, Figure 3 FIG. 1 shows a structural diagram of a bellows simulation member according to an embodiment of the present invention, as shown in FIG. Figure 3 As shown, the bellows simulator adopts a double helix structure, and two spiral grooves 2073 are provided on the bellows simulator, wherein the starting point and the end point of the spiral groove are 90° apart, and the starting point and the end point of the other spiral groove are distributed 90° apart, so that the starting point and the end point of the two spiral grooves are perpendicular to each other in space. This perpendicular state makes the pitches between the two spiral grooves equal, so that the forces on the spiral grooves in the axial, circumferential and radial directions are consistent, thereby ensuring that the bending stiffness of the bellows simulator in different directions is consistent, so that the bending stiffness of the bellows simulated by the bellows simulator is more accurate.

[0036] At the same time, ifFigure 3 As shown, in order to reduce the stress concentration of the starting point and the ending point of the spiral groove, at least one end of each spiral groove 2073 is provided with a stress hole 2072, here, the stress hole 2072 of the spiral groove can be arranged at the starting point, the stress hole 2072 of the spiral groove can be arranged at the starting point and the ending point, and the stress hole 2072 of the spiral groove can be arranged at the ending point. The hole diameter of the stress hole 2072 is larger than the groove width of the spiral groove, which not only offsets the stress generated by the bellows simulation piece during movement, but also improves the service life of the bellows simulation piece.

[0037] In an alternative way, as shown in Figure 3 The bellows simulation piece also has a through hole 2071, and the axial direction of the through hole 2071 is the same as the distribution direction of the two end faces. The bellows is actually an elastic piece with a spring as the main structure, and the bellows simulation piece 207 is used to simulate the spring, so the bellows simulation piece 207 is a spring body with an internal hollow cylindrical structure, that is, the bellows simulation piece has a through hole 2071, and the axial direction of the through hole is the same as the distribution direction of the two end faces.

[0038] In order to more accurately simulate the bending stiffness, bending angle and elastic moment load parameters that the bellows can generate during movement, a through hole is provided in the bellows simulation piece, and the axial direction of the through hole is the same as the distribution direction of the two end faces. This structure is more like a spring body with an internal hollow cylindrical structure, and the bending stiffness, bending angle and elastic moment load parameters of the bellows simulated by the bellows simulation piece are more accurate.

[0039] In an alternative way, the swing mechanism includes a frame and a first direction swing shaft and a second direction swing shaft arranged on the frame, the axial directions of the first direction swing shaft and the second direction swing shaft are different, and the fixed connecting piece is connected with the first direction swing shaft and the second direction swing shaft respectively.

[0040] In actual application, as shown in Figure 2 When the engine moves to drive the swing mechanism to start swinging, the swing mechanism 206 is a frame structure, the first direction swing shaft 204 arranged on the frame starts to swing along the first direction, and the second direction swing shaft 205 arranged on the frame starts to swing along the second direction. The movement state of the swing mechanism swinging in the first direction and the second direction is the movement state generated by the bellows during movement.

[0041] Compared with the prior art, the swing mechanism provided by the present application is used for simulating the motion state of the bellows simulation piece when the bellows simulation piece is in motion. When the bellows simulation piece starts to move, the swing mechanism connected by the fixed connecting piece is subjected to a pulling force or a pressure in the first direction, and the swing mechanism connected by the fixed connecting piece is subjected to a pulling force or a pressure in the second direction. Due to the different pulling forces or pressures in the first direction, the swing mechanism is subjected to different pulling forces or pressures in the second direction, so that the swing mechanism swings in the second direction. Similarly, when the swing mechanism is subjected to different pulling forces or pressures in the second direction, the swing mechanism is subjected to different pulling forces or pressures in the first direction, so that the swing mechanism swings in the first direction. When the swing mechanism starts to swing, the bellows simulation piece is measured to accurately obtain the bending stiffness, bending angle and elastic moment load of the bellows.

[0042] For example, as shown in Figure 4 In order to more accurately simulate the bending stiffness, bending angle and elastic moment load of the bellows in the first direction and the second direction, the fixed connecting piece is connected to the swing mechanism through the rotating bearing 2051 in the first direction swing shaft, and the shaft sleeve 2052 is sleeved on the rotating bearing 2051 and rotatably connected to the swing mechanism. The fixed connecting piece is connected to the swing mechanism through the rotating bearing 2051 in the second direction swing shaft, and the shaft sleeve 2052 is sleeved on the rotating bearing 2051 and rotatably connected to the swing mechanism. The rotating bearing can be a self-lubricating radial bearing or other forms of bearings, which will not be described here.

[0043] For example, the frame has two groups of accommodating grooves, and the part of the fixed connecting piece away from the corresponding end face is movably installed in the accommodating groove. Each direction swing shaft penetrates the groove wall of the corresponding accommodating groove, and each direction swing shaft is connected with the corresponding fixed connecting piece. The end of the fixed connecting piece away from the corresponding end face is in an arc structure.

[0044] In actual application, as shown in Figure 4 The groove depth direction of the accommodating groove 209 is parallel to the direction of the fixed connecting piece. Each direction swing shaft penetrates the groove wall of the corresponding accommodating groove. The first direction swing shaft penetrates the rotatable connection of the fixed connecting piece. The second direction swing shaft penetrates the rotatable connection of the fixed connecting piece. The radial dimension of the arc structure of the corresponding mounting piece is greater than the radial dimension of the accommodating groove.

[0045] As can be known from the above implementation process, when the radial dimension of the arc structure of each mounting piece is greater than the radial dimension of the accommodating groove, in order to prevent the bellows simulation piece from swinging greatly, the swing mechanism can be limited to swing greatly when the swing mechanism starts to swing, so as to ensure that the bellows simulation piece is measured to accurately obtain the bending stiffness, bending angle and elastic moment load of the bellows when the swing mechanism starts to swing.

[0046] The above merely illustrates the specific embodiments of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of the changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A bellows elastic load equivalent device, characterized in that: include: a bellows dummy, the bellows dummy having two opposite end surfaces, one of the two end surfaces being connected to a frame of an engine, and the other end surface being connected to a nozzle of the engine; The bellows elastic load equivalent device further includes a swing mechanism and two fixed connectors, the swing mechanism is respectively connected to the two fixed connectors, each of the fixed connectors is provided on the corresponding end surface, and the bellows simulation part has a spiral groove extending spirally along the distribution direction of the two end surfaces; The bellows elastic load equivalent device further comprises: two mounting structures, each of the mounting structures being arranged on the corresponding end surface.

2. The bellows elastic load equivalent device according to claim 1, characterized in that: There are multiple spiral grooves, each of which has the same pitch, and the multiple spiral grooves are distributed along the distribution direction of the two end surfaces.

3. The bellows elastic load equivalent device according to claim 2, characterized in that: In two adjacent spiral grooves, the end point of one spiral groove and the starting point of the other spiral groove are located on the same plane.

4. The bellows elastic load equivalent device according to claim 2, characterized in that: In the orthographic projection of one of the end faces, the end projections of the plurality of spiral grooves are evenly distributed along an annular trajectory.

5. The bellows elastic load equivalent device according to claim 2, characterized in that: At least one end portion of each spiral groove is provided with a stress hole, and the diameter of the stress hole is larger than the groove width of the corresponding spiral groove.

6. The bellows elastic load equivalent device according to any one of claims 1 to 5, characterized in that: The bellows simulation component further has a through hole, and the axial direction of the through hole is the same as the distribution direction of the two end surfaces.

7. The bellows elastic load equivalent device according to any one of claims 1 to 5, characterized in that: The swing mechanism includes a frame and a first direction swing shaft and a second direction swing shaft arranged on the frame. The first direction swing shaft and the second direction swing shaft have different axial directions, and the fixed connection is rotationally connected to the first direction swing shaft and the second direction swing shaft respectively.

8. The bellows elastic load equivalent device according to claim 7, characterized in that: The axial directions of the first direction swing axis and the second direction swing axis are perpendicular.

9. The bellows elastic load equivalent device according to claim 7, characterized in that: The frame has two groups of accommodating grooves, and the part of each fixed connection away from the corresponding end surface can be movably installed in the accommodating groove. Each directional swing shaft passes through the groove wall of the corresponding accommodating groove. Each directional swing shaft is rotatably connected to the corresponding fixed connection, and the end of the fixed connection away from the corresponding end surface is an arc-shaped structure.

10. The bellows elastic load equivalent device according to claim 7, characterized in that: One end face of the bellows simulation part has a first mounting part extending along a first direction, and the other end face has a second mounting part extending along a second direction. The first mounting part and the first direction swing shaft are connected by a fixed connecting part, and the second mounting part and the second direction swing shaft are connected by a fixed connecting part.

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