A sound pressure acquisition device and method for fluid machinery fault signal

Abstract

The present application discloses a device and method for collecting sound pressure of fluid machinery fault signals, which relates to the technical field of fluid machinery fault diagnosis, and includes: an air chamber and a sensor chamber that are interconnected, wherein a sound pressure sensor is arranged in the sensor chamber, a coil is arranged around the air chamber, and the top of the air chamber is a variable stiffness diaphragm, wherein a magnetorheological microtube filled with magnetorheological fluid is arranged in the variable stiffness diaphragm. When the fluid flows through the pipeline, vibration is generated, and the vibration of the pipeline causes the vibration of the variable stiffness diaphragm, which in turn causes the vibration of the air in the air chamber; the vibration of the air is finally captured by the sound pressure sensor through the vent hole connecting the air chamber and the sensor chamber. The stiffness and natural frequency of the variable stiffness diaphragm can change continuously with the change of the coil current, which expands the frequency range of the fault signal that can be captured by the sound pressure sensor, so that more types of fluid machinery faults can be diagnosed.

Description

Technical Field

[0001] The present application relates to the technical field of fluid machinery fault diagnosis, and in particular to a device and method for collecting sound pressure of fluid machinery fault signals. Background Art

[0002] In the modern machinery industry, fluid machinery is widely used, such as hydraulic transmission systems, pneumatic transmission systems, etc. Once a fluid machinery fails, it needs to be eliminated manually based on experience. The whole process is time-consuming, labor-intensive and highly dependent on human experience.

[0003] At present, fluid machinery fault diagnosis technology based on machine learning has been applied, such as intelligent fault diagnosis based on oil pressure signals and flow signals, which can automatically output fault categories by computer programs. In this field, the most promising application scenario is to capture sensor signals and extract fault features when the fluid state changes, and then output fault categories through machine learning models.

[0004] However, the response time of oil pressure sensors and flow sensors widely used in industry is limited. For example, the response time of a typical diffused silicon oil pressure sensor ranges from a few milliseconds to hundreds of milliseconds, making it difficult to capture fault information hidden in high-frequency pressure pulsations. The response time of the flow sensor is even slower, which greatly limits the computer's ability to capture useful signals, and thus only a few types of faults can be diagnosed. Summary of the invention

[0005] In order to solve the above technical problems, this application proposes the following technical solutions:

[0006] In the first aspect, an embodiment of the present application provides a sound pressure collection device for fluid machinery fault signals, comprising: an air chamber and a sensor chamber that are interconnected, a sound pressure sensor is arranged in the sensor chamber, a coil is wound around the air chamber, the top of the air chamber is a variable stiffness diaphragm, and magnetorheological microtubes filled with magnetorheological fluid are arranged in the variable stiffness diaphragm.

[0007] In one possible implementation, the air chamber includes a base partition that separates the air chamber and the sensor chamber, a first base sleeve arranged on one side of the base partition, a first cover body threadedly connected to the first base sleeve, and the variable stiffness diaphragm is clamped on the top of the first base sleeve; a wire groove is arranged on the first base sleeve, and the coil is wound and arranged in the wire groove.

[0008] In a possible implementation, the base partition is provided with a groove corresponding to the center position of the axis of the first base sleeve, and a cylindrical iron core is provided in the groove. The iron core helps to bind the magnetic flux lines generated after the coil is energized, so that more magnetic flux lines pass through the area where the magnetorheological microtubes are located.

[0009] In a possible implementation, the variable stiffness diaphragm is a circular boss, the magnetorheological microtube is parallel to the upper and lower end surfaces of the circular boss and closed at both ends, and the outer edge protrusion of the variable stiffness diaphragm is stuck in the groove formed by the first cover body and the first base sleeve.

[0010] In a possible implementation, the magnetorheological microtubes are routed in a circuitous manner inside the variable stiffness diaphragm to increase the total volume of the tubes so that more magnetorheological fluid can be filled.

[0011] In one possible implementation, the sensor chamber includes a second base sleeve arranged on the other side of the base partition, the tube diameter of the second base sleeve is smaller than that of the first base sleeve, the first base sleeve and the second base sleeve are connected through a vent hole arranged on the base partition, the bottom of the second base sleeve is threadedly connected to the second cover body, and the sound pressure sensor is fixedly set on the second cover body.

[0012] In a possible implementation, the sound pressure sensor is electrically connected to the signal recognition device via a signal line, the signal line passes through the second cover, and the outer wall of the signal line is tightly fitted to the inside of the through hole.

[0013] In a second aspect, an embodiment of the present application provides a method for collecting sound pressure of a fluid machinery fault signal, using the device for collecting sound pressure of a fluid machinery fault signal described in any possible implementation of the first aspect, the method comprising:

[0014] The variable stiffness diaphragm of the sound pressure collection device is fitted onto the surface of the square pipe to be tested;

[0015] When the fluid flows through the pipe, it generates vibrations, which cause the variable stiffness diaphragm to vibrate, and then cause the air in the air chamber to vibrate. The vibrations of the air are finally captured by the sound pressure sensor through the vent hole connecting the air chamber and the sensor chamber.

[0016] If a fluid machine fails, the vibration frequency and vibration intensity caused by the fluid flowing through the square pipe to be tested will change. The fault type can be diagnosed based on the electrical signal fed back by the sound pressure sensor combined with a mature machine learning algorithm.

[0017] If the feedback signal of the sound pressure sensor is weak when it fails, current is applied to the coil, and the magnetic flux lines generated thereby pass through the magnetorheological fluid in the magnetorheological microtube, causing the viscosity of the magnetorheological fluid to change, thereby changing the stiffness and natural frequency of the variable stiffness diaphragm, thereby changing the air vibration frequency caused by the faulty fluid, making it easier to be captured by the sound pressure sensor.

[0018] In the embodiment of the present application, when the fluid flows through the pipeline, it generates vibrations, and the vibrations of the pipeline cause the vibrations of the variable stiffness diaphragm, which in turn causes the vibrations of the air in the air chamber; the vibrations of the air are finally captured by the sound pressure sensor through the vent holes connecting the air chamber and the sensor chamber. The stiffness and natural frequency of the variable stiffness diaphragm can change continuously with the change of the coil current, which expands the frequency range of the fault signal that can be captured by the sound pressure sensor, so that more types of fluid machinery faults can be diagnosed. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic diagram of the structure of a sound pressure collection device for a fluid machinery fault signal provided in an embodiment of the present application;

[0020] Figure 2 A schematic diagram of the arrangement of the magnetorheological microtubes in the variable stiffness diaphragm provided in the embodiment of the present application;

[0021] Figure 3 A schematic flow chart of a method for collecting sound pressure of a fluid machinery fault signal provided in an embodiment of the present application;

[0022] Figure 4 A schematic diagram of a signal collection device for collecting sound pressure signals of a fluid machinery fault signal provided in an embodiment of the present application;

[0023] Figure 1-Figure 4 In the symbol, it is represented as:

[0024] 1-air chamber, 2-sensor chamber, 3-sound pressure sensor, 4-coil, 5-variable stiffness diaphragm, 6-magnetorheological microtube, 7-base partition, 8-first base sleeve, 9-first cover, 10-wire slot, 11-groove, 12-cylindrical iron core, 13-magnetic flux line, 14-second base sleeve, 15-vent, 16-second cover, 17-signal line. DETAILED DESCRIPTION

[0025] The present solution is described below in conjunction with the accompanying drawings and specific implementation methods.

[0026] See also Figure 1 The sound pressure collection device for fluid machinery fault signals provided in the embodiment of the present application includes an air chamber 1 and a sensor chamber 2 which are interconnected. A sound pressure sensor 3 is arranged in the sensor chamber 2. A coil 4 is wound around the air chamber 1. The top of the air chamber 1 is a variable stiffness diaphragm 5. A magnetorheological microtube 6 filled with magnetorheological fluid is arranged in the variable stiffness diaphragm 5.

[0027] See also Figure 1The air chamber 1 in this embodiment includes a base partition 7 for separating the air chamber 1 and the sensor chamber 2, a first base sleeve 8 provided on one side of the base partition 7, a first cover 9 threadedly connected to the first base sleeve 8, and the variable stiffness diaphragm 5 is clamped on the top of the first base sleeve 8. A wire groove 10 is provided on the first base sleeve 8, and the coil 4 is wound and arranged in the wire groove 10.

[0028] The base partition 7 is provided with a groove 11 at the center position of the axis of the first base sleeve 8, and a cylindrical iron core 12 is provided in the groove 11. The cylindrical iron core 12 helps to bind the magnetic flux lines 13 generated after the coil 4 is energized, so that the magnetic flux lines 13 pass more through the area where the magnetorheological microtube 6 is located.

[0029] The variable stiffness diaphragm 5 is a circular boss, the magnetorheological microtube 6 is parallel to the upper and lower end surfaces of the circular boss and closed at both ends, and the outer edge protrusion of the variable stiffness diaphragm 5 is clamped in the groove 11 formed by the first cover body 9 and the first base sleeve 8. Figure 2 The magnetorheological microtube 6 is routed in a circuitous manner inside the variable stiffness diaphragm 5 to increase the total volume of the tube so that it can be filled with more magnetorheological fluid.

[0030] In this embodiment, the sensor chamber 2 includes a second base sleeve 14 disposed on the other side of the base partition 7, the barrel diameter of the second base sleeve 14 is smaller than the first base sleeve 8, the first base sleeve 8 and the second base sleeve 14 are connected through a vent hole 15 disposed on the base partition 7, the bottom of the second base sleeve 14 is threadedly connected to the second cover 16, and the sound pressure sensor 3 is fixedly disposed on the second cover 16. The sound pressure sensor 3 is electrically connected to the signal recognition device through a signal line 17, the signal line 17 passes through the second cover 16, and the outer wall of the signal line 17 is tightly fitted with the inside of the perforation.

[0031] When the fluid flows through the pipeline, it vibrates, and the vibration of the pipeline causes the vibration of the variable stiffness diaphragm 5, which in turn causes the vibration of the air in the air chamber 1; the vibration of the air is finally captured by the sound pressure sensor 3 through the vent 15 connecting the air chamber 1 and the sensor chamber 2. The stiffness and natural frequency of the variable stiffness diaphragm 5 can change continuously with the change of the current of the coil 4, which expands the frequency range of the fault signal that can be captured by the sound pressure sensor 3, so that more types of fluid machinery faults can be diagnosed.

[0032] Corresponding to the device for collecting sound pressure of a fluid machinery fault signal provided in the above-mentioned embodiment, the present application also provides an embodiment of a method for collecting sound pressure of a fluid machinery fault signal.

[0033] See also Figure 3The method for collecting the sound pressure of the fluid machinery fault signal in this embodiment includes:

[0034] S101, attaching the variable stiffness diaphragm of the sound pressure collection device to the surface of the square pipe to be tested, such as Figure 4 shown.

[0035] S102, when the fluid flows through the pipe, vibration is generated, and the vibration of the pipe causes the vibration of the variable stiffness diaphragm, which in turn causes the vibration of the air in the air chamber; the vibration of the air is finally captured by the sound pressure sensor through the vent hole connecting the air chamber and the sensor chamber.

[0036] S103, if a fluid machinery fails, the vibration frequency and vibration intensity caused by the fluid flowing through the square pipe to be tested will change. The fault type can be diagnosed based on the electrical signal feedback from the sound pressure sensor combined with a mature machine learning algorithm.

[0037] S104, if the feedback signal of the sound pressure sensor is weak when it fails, current is applied to the coil, and the magnetic flux lines generated thereby pass through the magnetorheological fluid in the magnetorheological microtube, causing the viscosity of the magnetorheological fluid to change, thereby changing the stiffness and natural frequency of the variable stiffness diaphragm, thereby changing the air vibration frequency caused by the faulty fluid, making it easier to be captured by the sound pressure sensor.

[0038] By applying different currents in the coil, the stiffness and natural frequency of the variable stiffness diaphragm are different, so that the frequency of air vibration caused by the fault fluid changes, making it easier to be captured by the sound pressure sensor. The iron core helps to bind the magnetic flux lines so that they pass more through the area where the magnetorheological microtube is located.

[0039] In the embodiments of the present application, "at least one" refers to one or more, and "plurality" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent the existence of A alone, the existence of A and B at the same time, and the existence of B alone. Among them, A and B can be singular or plural. The character " / " generally indicates that the previous and subsequent associated objects are in an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b and c can be represented by: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.

[0040] The above is only a specific implementation of the present application. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. The protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A sound pressure collection device for fluid machinery fault signals, characterized in that: include: An air chamber and a sensor chamber are interconnected, wherein a sound pressure sensor is arranged in the sensor chamber, a coil is wound around the air chamber, a variable stiffness diaphragm is arranged on the top of the air chamber, and a magnetorheological microtube filled with magnetorheological fluid is arranged in the variable stiffness diaphragm; The air chamber comprises a base partition separating the air chamber and the sensor chamber, a first base sleeve arranged on one side of the base partition, a first cover body threadedly connected to the first base sleeve, and the variable stiffness diaphragm is clamped on the top of the first base sleeve; a wire groove is arranged on the first base sleeve, and the coil is wound and arranged in the wire groove; The base partition is provided with a groove at a central position corresponding to the axis of the first base sleeve, and a cylindrical iron core is provided in the groove, which helps to bind the magnetic flux lines generated after the coil is energized, so that more magnetic flux lines pass through the area where the magnetorheological microtube is located; The variable stiffness diaphragm is a circular boss, the magnetorheological microtube is parallel to the upper and lower end surfaces of the circular boss and both ends are closed, and the outer edge protrusion of the variable stiffness diaphragm is clamped in the groove formed by the first cover body and the first base sleeve; The magnetorheological microtubes are routed in a circuitous manner inside the variable stiffness diaphragm to increase the total volume of the tubes so that more magnetorheological fluid can be filled; The sensor chamber comprises a second base sleeve arranged on the other side of the base partition, the diameter of the second base sleeve is smaller than that of the first base sleeve, the first base sleeve and the second base sleeve are connected through a vent hole arranged on the base partition, the bottom of the second base sleeve is threadedly connected to the second cover body, and the sound pressure sensor is fixedly arranged on the second cover body; The sound pressure sensor is electrically connected to the signal recognition device via a signal line, the signal line passes through the second cover, and the outer wall of the signal line is tightly fitted with the inside of the through hole.

2. A method for collecting sound pressure of fluid machinery fault signals, characterized in that: Using the sound pressure acquisition device for fluid machinery fault signals according to claim 1, the method comprises: The variable stiffness diaphragm of the sound pressure collection device is fitted onto the surface of the square pipe to be tested; When the fluid flows through the pipe, it generates vibrations, which cause the variable stiffness diaphragm to vibrate, and then cause the air in the air chamber to vibrate. The vibrations of the air are finally captured by the sound pressure sensor through the vent hole connecting the air chamber and the sensor chamber. If a fluid machine fails, the vibration frequency and vibration intensity caused by the fluid flowing through the square pipe to be tested will change. The fault type can be diagnosed based on the electrical signal fed back by the sound pressure sensor combined with a mature machine learning algorithm. If the feedback signal of the sound pressure sensor is weak when it fails, current is applied to the coil, and the magnetic flux lines generated thereby pass through the magnetorheological fluid in the magnetorheological microtube, causing the viscosity of the magnetorheological fluid to change, thereby changing the stiffness and natural frequency of the variable stiffness diaphragm, thereby changing the air vibration frequency caused by the faulty fluid, making it easier to be captured by the sound pressure sensor.

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