A gas bearing film pressure testing device and method based on bearing micro-deformation

Abstract

This invention discloses a gas bearing film pressure testing device and method based on the micro-deformation of the bearing bush, relating to the field of gas bearing performance testing technology. The device includes: a gas bearing, comprising a bearing bush and a bearing sleeve; multiple preset pressure testing grooves are provided on the bearing bush; multiple strain gauges are disposed within the multiple preset pressure testing grooves; a data acquisition module is connected to the multiple strain gauges for acquiring the pressure signals from the strain gauges; a signal processing terminal is connected to the data acquisition module for receiving the pressure signals; wherein, the bearing bush is an integral structure without openings on its surface, and the multiple preset pressure testing grooves are disposed on the surface of the bearing bush near the bearing sleeve. The technical solution provided by this invention does not require openings in the bearing bush and does not disrupt the film flow field, offering advantages such as non-destructive operation, low cost, high precision, and online measurement capability. Furthermore, the strain gauges are located on the outside of the bearing bush during measurement, not within the film, making it applicable even when the film gap is very small.

Description

Technical Field

[0001] This invention relates to the technical field of gas bearing performance testing equipment, and in particular to a gas bearing film pressure testing device and method based on bearing micro-deformation. Background Technology

[0002] Gas bearings rely on a gas film for non-contact support, offering advantages such as ultra-low friction, high precision, long lifespan, and oil-free operation. They are widely used in high-end precision equipment, high-speed spindles, and semiconductor processing equipment, and are the mainstream choice for spindle systems in wafer thinning and polishing machines and workpiece stage guides in lithography machines. Among these, gas film pressure is a core parameter characterizing the load-bearing capacity, stiffness, and flow field stability of gas bearings. Accurate testing of the gas film pressure distribution and its dynamic changes is crucial for the structural design and performance optimization of gas bearings.

[0003] The existing gas bearing film pressure testing technologies mainly include the following methods: First, the perforated pressure testing method, which requires opening a pressure-inducing hole in the inner wall of the bearing bush or thrust plate, and collecting data through a pressure sensor connected to the air inlet pipe. However, opening the hole will damage the integrity of the inner wall of the bearing bush, disturb the distribution of the gas film flow field, and lead to distorted test results. Second, the embedded sensor testing method, which places a miniature pressure sensor into the gas film gap. Although it avoids opening the hole, the sensor installation process is complex and costly. It is also susceptible to centrifugal force and vibration interference under high-speed conditions, and is not suitable when the gas film gap is small. Third, the optical non-contact testing method, which does not require modification of the bearing structure, but the equipment cost is extremely high and the testing environment requirements are stringent, making it difficult to promote in large quantities in laboratories and engineering sites.

[0004] In summary, the existing technology has the following problems:

[0005] It cannot simultaneously meet the requirements of non-destructive, low-cost, high-precision, and versatility, and is not applicable when the air-film spacing is small. Summary of the Invention

[0006] To address the shortcomings of existing technologies that fail to simultaneously meet the requirements of non-destructive testing, low cost, high precision, and versatility, and are unsuitable for applications with small gas film spacing, this invention provides a gas bearing gas film pressure testing device and method based on bearing micro-deformation. The technical solution is as follows:

[0007] On one hand, a gas bearing film pressure testing device based on micro-deformation of the bearing bush is provided. The testing device includes: a gas bearing, which includes a rotor, a bearing bush, and a bearing sleeve disposed on the outside of the bearing bush. The bearing bush is an integral structure with a complete inner surface. A preset pressure testing groove is provided, and the gas film of the gas bearing is located on the side of the bearing bush closer to the rotating shaft; multiple strain gauges are disposed on the side of the bearing bush away from the gas film, which is in the preset pressure testing groove; a data acquisition module is communicatively connected to the multiple strain gauges and is used to acquire the strain signals of the multiple strain gauges; and a signal processing terminal is communicatively connected to the data acquisition module and is used to receive and process the strain signals.

[0008] Optionally, the bearing bush has a plurality of preset pressure test grooves on the surface away from the gas film, and the plurality of strain gauges are disposed in the plurality of preset pressure test grooves.

[0009] Optionally, the plurality of strain gauges are arranged in an array and electrically connected to the data acquisition module via shielded wires; wherein, the plurality of strain gauges are interconnected via a temperature drift compensation circuit, and the plurality of strain gauges are externally encapsulated with insulating and waterproof adhesive.

[0010] Optionally, the plurality of strain gauges are uniaxial strain gauges, or the strain gauges are strain flowers.

[0011] Optionally, the testing device further includes a calibration component, which includes: a sealing end cap, wherein the bearing sleeve and the sealing end cap together form a cavity, and the gas film of the gas bearing is located in the cavity; a sealing ring is provided between the bearing bush and the sealing end cap; and a gas path pressure stabilizing module, which is connected to the cavity and is used to control the pressure of the gas film.

[0012] Optionally, the testing device further includes: multiple air supply holes, which are disposed on the bearing bush, and the air circuit stabilizing module is connected to the cavity through the multiple air supply holes.

[0013] On the other hand, the present invention also provides a gas bearing film pressure testing method based on bearing micro-deformation. The testing method includes the following steps: S1, multiple strain gauges are arranged in multiple preset pressure testing grooves of the gas bearing bearing shell. The multiple strain gauges are connected to a data acquisition module, and the data acquisition module is connected to a signal processing terminal. The signal processing terminal includes a calibration model unit, a signal preprocessing unit, and a pressure inversion unit. The multiple preset pressure testing grooves are arranged on the surface of the bearing shell away from the center of the gas bearing. S2, the bearing shell is placed under the test condition, and the data acquisition module receives the real-time film pressure signals from the multiple strain gauges when the gas bearing is working. S3, the signal preprocessing unit filters the real-time film pressure signals to obtain processed real-time film pressure signals, and the pressure inversion unit obtains the real-time film pressure value based on the real-time film pressure signals and the mathematical model.

[0014] Optionally, before step S1, the following steps are also included: S4, grinding and degreasing the bearing bush of the gas bearing; setting multiple strain gauges in multiple preset pressure test grooves of the bearing bush; S5, calibrating the gas bearing using a calibration component to establish a mathematical model relating the pressure signal and the gas pressure signal.

[0015] Optionally, step S5 includes: S51, placing the gas bearing in the calibration assembly; wherein the calibration assembly includes a sealing end cap, the sealing end cap and the bearing sleeve of the gas bearing together form a cavity; the calibration assembly also includes a gas path pressure stabilizing module, the gas path pressure stabilizing module being connected to the cavity; S52, when the bearing bush is a radial bearing bush, the gas path pressure stabilizing module applies gas pressure to the inner wall of the radial bearing bush; when the bearing bush is a thrust bearing thrust plate, the gas path pressure stabilizing module applies gas pressure to the pressure bearing surface of the thrust bearing thrust plate; S53, the data acquisition module receives the pressure signals output by the multiple strain gauges and transmits them to the signal processing terminal; S54, the calibration model unit establishes a mathematical model relating the pressure signal and the gas pressure value, wherein the mathematical model is established using a linear fitting method.

[0016] Optionally, in step S3: the filtering process includes first performing median filtering on the real-time air film pressure signal, and then performing low-pass filtering on the real-time air film pressure signal.

[0017] The beneficial effects of the technical solutions provided in the embodiments of the present invention include at least the following:

[0018] Gas bearing bushes undergo minute elastic deformation under film pressure. By attaching strain gauges to the back of the bush, the elastic deformation signal of the bush under film pressure is collected. A mathematical model corresponding to the output signal and pressure is established through signal processing terminal calibration, and the film pressure data is obtained through inversion. The supporting device can be flexibly adapted to radial and thrust bearings, supporting online real-time measurement after bearing installation. Therefore, it can achieve measurement without drilling holes or disrupting the film flow field, offering advantages such as non-destructive, low-cost, high-precision, highly versatile, and online measurement capabilities. It can be widely used for static and dynamic film pressure testing of various hydrostatic and hydrodynamic gas radial and thrust bearings, effectively overcoming the shortcomings of existing testing technologies and possessing high engineering application value. Furthermore, in this case, the strain gauges are located on the outside of the bush, not inside the film, thus remaining applicable even with very small film gaps, perfectly meeting the needs of ultra-precision spindles. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This invention provides a hydrostatic gas radial bearing film pressure testing device based on bearing micro-deformation;

[0021] Figure 2 This is a schematic diagram of a calibration component for a static pressure gas radial bearing film pressure testing system provided in an embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of a calibration component for a dynamic pressure gas radial bearing film pressure testing system provided in an embodiment of the present invention;

[0023] Figure 4 This invention provides a hydrostatic gas thrust bearing film pressure testing device based on the micro-deformation of the bearing bush;

[0024] Figure 5 This is a schematic diagram of a calibration component for a hydrostatic gas thrust bearing film pressure testing system provided in an embodiment of the present invention;

[0025] Figure 6 This is a graph showing the change of bridge voltage with gas supply pressure in an embodiment of the present invention;

[0026] Among them, 1-bearing sleeve; 2-bearing bush; 3-strain gauge; 4-data acquisition module; 5-signal processing terminal; 6-sealing end cap; 7-gas circuit pressure stabilizing module; 8-gas film. Detailed Implementation

[0027] The technical solution of the present invention will now be described with reference to the accompanying drawings.

[0028] In embodiments of the present invention, words such as "exemplarily," "for example," etc., are used to indicate that something is an example, illustration, or description. Any embodiment or design described as "exemplary" in the present invention should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of the word "exemplary" is intended to present the concept in a concrete manner. Furthermore, in embodiments of the present invention, the meaning expressed by "and / or" can be both, or either one.

[0029] In the embodiments of this invention, the terms "image" and "picture" may sometimes be used interchangeably. It should be noted that, without emphasizing the distinction between them, they convey the same meaning. Similarly, the terms "of," "corresponding (relevant)," and "corresponding" may sometimes be used interchangeably. It should be noted that, without emphasizing the distinction between them, they convey the same meaning.

[0030] In this embodiment of the invention, sometimes a subscript such as W1 may be written in a non-subscript form such as W1. When the difference is not emphasized, the meaning they express is the same.

[0031] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0032] This invention provides a gas bearing film pressure testing device based on the micro-deformation of the bearing bush. For example... Figure 1 The illustrated hydrostatic gas radial bearing film pressure testing device based on bearing bush micro-deformation includes: a gas bearing comprising a rotor, a bearing bush 2, and a bearing sleeve 1 disposed on the outside of the bearing bush 2; the bearing bush 2 is an integral structure with a pre-set pressure testing groove on its inner surface; the gas film 8 of the gas bearing is located on the side of the bearing bush 2 closer to the rotating shaft; multiple strain gauges 3 disposed on the side of the bearing bush 2 away from the gas film 8 in the pre-set pressure testing groove; a data acquisition module 4 communicatively connected to the multiple strain gauges 3 for acquiring the strain signals of the multiple strain gauges 3; and a signal processing terminal 5 communicatively connected to the data acquisition module 4 for receiving and processing the strain signals.

[0033] The gas bearing bush 2 provided in this embodiment of the invention undergoes slight elastic deformation under gas film pressure. By attaching strain gauges 3 to the back of the bush 2, the elastic deformation signal of the bush 2 under gas film pressure is collected. A mathematical model corresponding to the output signal and pressure is established through signal processing terminal 5, and the gas film pressure data is obtained through inversion. The device can be flexibly adapted to radial bearings and thrust bearings. Only the strain gauges 3 need to be placed at the corresponding bush positions of the radial or thrust bearings, without replacing core components. It supports online real-time measurement after bearing installation. Furthermore, the device does not require drilling or disrupt the gas film flow field during use, offering advantages such as non-destructive operation, low cost, high precision, strong versatility, and online measurement capability. It can be widely used for static and dynamic gas film pressure testing of various hydrostatic and hydrodynamic gas radial and thrust bearings, effectively addressing the shortcomings of existing testing technologies and possessing high engineering application value. Moreover, in this measurement, the strain gauges 3 are located on the outside of the bush 2, not inside the gas film, thus remaining applicable even with very small gas film gaps, meeting the requirements of ultra-precision spindles.

[0034] In this embodiment of the invention, the bearing bush 2 refers to a radial bearing bearing bush or a thrust bearing thrust plate.

[0035] Optionally, the bearing bush 2 has multiple preset pressure testing grooves on its surface away from the air film 8, and the multiple strain gauges 3 are disposed within these grooves. Optionally, the multiple strain gauges 3 are arranged in an array and electrically connected to the data acquisition module 4 via shielded wires; wherein the multiple strain gauges 3 are interconnected via a temperature drift compensation circuit, and the external components of the multiple strain gauges 3 are encapsulated with insulating and waterproof adhesive. The temperature drift compensation circuit can compensate for signal drift between the strain gauges 3 caused by temperature changes, and the insulating and waterproof encapsulation adhesive can ensure that the strain gauges 3 are not contaminated by moisture.

[0036] Optionally, the plurality of strain gauges 3 are uniaxial strain gauges 3, or the strain gauges 3 are strain flowers. The plurality of strain gauges 3 are arranged circumferentially and axially along the bearing bush 2, or arranged in a multi-point array radially and circumferentially along the thrust plate, to achieve distributed acquisition of film pressure.

[0037] Optionally, such as Figure 2 , Figure 3 and Figure 5 As shown, the testing device also includes a calibration component, which includes: a sealing end cap 6, the bearing sleeve 1 and the sealing end cap 6 together forming a cavity, and the gas film of the gas bearing is located in the cavity; a sealing ring is provided between the bearing bush 2 and the sealing end cap 6; and a gas path pressure stabilizing module 7, which is connected to the cavity and is used to control the pressure of the gas film.

[0038] Among them, strain gauge 3 is sealed with insulating and waterproof adhesive after being pasted, and temperature drift compensation is achieved through half-bridge or full-bridge circuit connection.

[0039] Optionally, the testing device further includes: multiple air supply holes, which are disposed on the bearing bush 2, and the air circuit pressure stabilizing module 7 is connected to the cavity through the multiple air supply holes.

[0040] This invention also provides a method for testing the film pressure of a gas bearing based on the micro-deformation of the bearing bush, characterized in that the testing method includes the following steps:

[0041] S1. Multiple strain gauges 3 are installed in multiple preset pressure test grooves of the bearing shell 2 of the gas bearing. The multiple strain gauges 3 are connected to the data acquisition module 4. The data acquisition module 4 is connected to the signal processing terminal 5. The signal processing terminal 5 includes a calibration model unit, a signal preprocessing unit, and a pressure inversion unit. The multiple preset pressure test grooves are installed on the surface of the bearing shell 2 away from the center of the gas bearing.

[0042] S2. The bearing bush 2 is set to the test condition, and the data acquisition module 4 receives the real-time gas film pressure signal of the multiple strain gauges 3 when the gas bearing is working.

[0043] S3. The signal preprocessing unit filters the real-time air film pressure signal to obtain the processed real-time air film pressure signal, and the pressure inversion unit obtains the real-time air film pressure value based on the real-time air film pressure signal and the mathematical model.

[0044] Wherein, the bearing bush 2 is a radial bearing bearing bush 2 (e.g. Figure 1 and 2 ,or Figure 1 and 3 ), or thrust bearing thrust plate (such as Figure 4 and 5 ).

[0045] Compared with existing technologies, the gas film pressure testing method for gas bearings based on micro-deformation of the bearing bush provided by this invention has the following technical advantages: It adopts a back-mounting method for the bearing bush 2, which does not damage the inner wall of the bearing bush 2, does not require openings, and does not intrude into the gas film gap, thus completely preserving the original gas film flow field. The test results are more consistent with the actual operating conditions of the bearing, solving the problem of pressure measurement distortion caused by openings. Furthermore, this solution uses conventional strain gauges and acquisition equipment, which are inexpensive, have a simple assembly process, require no professional debugging, and are suitable for both laboratory R&D and batch testing in engineering fields. Moreover, the solution is compatible with various gas bearings such as radial bearings and thrust bearings, and can test both static pressure distribution and high-speed dynamic pressure fluctuations, adapting to the testing needs of bearings of different specifications and operating conditions. It eliminates the need to design special devices for different types of bearings, demonstrating strong versatility. Furthermore, the strain gauge 3 can be pasted after the bearing is installed (or pasted before assembly without affecting bearing installation), and the testing process does not require disassembling the bearing. It can acquire gas film pressure data in real time, meeting the needs of online monitoring, fault diagnosis, and performance evaluation in engineering fields. Furthermore, in step S2, the test condition is the actual use condition such as a test bench or spindle. When the bearing is working, the air film pressure causes the bearing bush 2 to undergo elastic deformation. The data acquisition module 4 receives the output signal of the strain gauge 3 under the deformation of the bearing bush 2.

[0046] Optionally, the strain gauge 3 can be pasted before the bearing is assembled, or it can be pasted on the operable area on the back of the bearing bush 2 after the gas bearing is installed, to meet the needs of online measurement.

[0047] Optionally, before step S1, the following steps are also included:

[0048] S4. Grind and degrease the bearing bush of the gas bearing; install multiple strain gauges in multiple preset pressure test grooves of the bearing bush;

[0049] S5. The gas bearing is calibrated using a calibration component to establish a mathematical model relating the pressure signal and the gas pressure signal.

[0050] Optionally, in S4, the back of the bearing shell 2 of the gas bearing to be tested is surface treated. First, the surface is sanded with fine sandpaper until it is smooth and flat, removing burrs and oxide layers. Then, it is wiped with acetone or anhydrous ethanol to degrease, ensuring that the bonding surface is clean and dry. Strain gauges 3 are precisely bonded to the corresponding gas film test area on the back of the bearing shell 2. The strain gauges 3 are connected to the strain acquisition module through shielded wires. The inner wall of the bearing shell 2 is kept in its original state throughout the process, without openings, to prevent disturbance of the gas film flow field. The bonding of strain gauges 3 can be completed before bearing assembly or after the bearing is installed in place, in the operable area on the back of the bearing shell 2, to meet online measurement requirements.

[0051] Optionally, step S5 includes:

[0052] S51. The gas bearing is placed in the calibration assembly; wherein, the calibration assembly includes a sealing end cap 6, the sealing end cap 6 and the bearing sleeve 1 of the gas bearing together form a cavity; the calibration assembly also includes a gas path pressure stabilizing module 7, the gas path pressure stabilizing module 7 is connected to the cavity;

[0053] S52. When the bearing bush 2 is a radial bearing bush 2, the gas path pressure stabilizing module 7 applies gas pressure (such as...) to the inner wall of the radial bearing bush 2. Figure 2 and Figure 3 When the bearing bush 2 acts as the thrust bearing thrust plate, the air circuit pressure stabilizing module 7 applies gas pressure (e.g., gas pressure) to the pressure-bearing surface of the thrust bearing thrust plate. Figure 5 );

[0054] S53, The data acquisition module 4 receives the pressure signals output by the plurality of strain gauges 3 and transmits them to the signal processing terminal 5;

[0055] S54. The calibration model unit establishes a mathematical model relating the pressure signal and the gas pressure value, wherein the mathematical model is established using a linear fitting method.

[0056] Furthermore, in Figure 2 , Figure 3 and Figure 5 In the calibration component, different levels of gas pressure are applied to the inner wall of the bearing bush 2. After each pressure level stabilizes, the output signal of the strain gauge 3 is collected synchronously. Through linear fitting, a calibration mathematical model between the strain gauge output value and the gas film pressure value is established. The calibration process can be completed offline, and the calibrated model can be directly used for online measurement without the need for repeated calibration.

[0057] Optionally, in step S5, the range of the real-time gas film pressure signal is within the range of the gas pressure signal. Thus, the calibration process is completed offline, and the calibrated mathematical model can be directly used for online measurement.

[0058] Optionally, in step S3, the filtering process includes first performing median filtering on the real-time air film pressure signal, and then performing low-pass filtering on the real-time air film pressure signal. This can remove gross errors and high-frequency noise caused by airflow disturbances, environmental vibrations, etc.

[0059] This invention also provides a more specific method and apparatus for testing the film pressure of a hydrostatic gas radial bearing, such as... Figure 1 and Figure 2 As shown, specifically, it includes the following steps:

[0060] First, the area to be tested on the back of the bearing bush 2 of the gas bearing is polished (roughness Ra0.8μm) and degreased with acetone. Two uniaxial strain gauges 3 are evenly pasted along the circumference of the bearing bush 2 and two uniaxial strain gauges 3 are pasted along the axial direction of the bearing bush 2 to form a full-bridge measurement circuit. The full-bridge measurement circuit is connected to the data acquisition module 4 through the reserved channel of the bearing sleeve 1 using shielded wires, without affecting the normal operation of the bearing.

[0061] Next, the gas bearing is installed in the calibration assembly, and sealing end caps 6 are assembled on both sides of the bearing bush 2, forming a sealed chamber between the end caps and the bearing bush 2. High-pressure gas is supplied to the sealed chamber through the gas path pressure stabilizing module 7, and the gas pressure can be precisely adjusted through the gas path pressure stabilizing module 7. Pressures of 0, 0.2, 0.4, 0.6, 0.8, and 1.0 MPa are supplied respectively, which are also called supply pressures, and the output voltage Uy of the strain gauge 3 bridge is collected, also called the bridge voltage, as shown in Table 1. The curve of the bridge voltage changing with the supply pressure P is plotted. Figure 6 By fitting the data using the least squares method, a calibration mathematical model for the bridge voltages Uy is obtained:

[0062]

[0063] Table 1. Test data of strain gauge bridge voltage and gas supply pressure

[0064] Gas supply pressure (MPa) Bridge voltage (mV) 0 0.25 0.2 4.06 0.4 8.29 0.6 12.56 0.8 16.03 1.0 20.03

[0065] Next, the gas bearing is installed into the spindle, the gas circuit is connected, and the spindle is started. The data acquisition module 4 is used to acquire the real-time gas film pressure signal output by the strain gauge 3 bridge, and the spindle speed and ambient temperature are recorded simultaneously to achieve online real-time acquisition;

[0066] Finally, the real-time air film pressure signal is denoised and filtered using signal processing terminal 5, and then substituted into the mathematical model to obtain the air film pressure of the bearing at that point.

[0067] This invention also provides a more specific method and apparatus for testing the film pressure of a dynamic gas radial bearing, such as... Figure 3 As shown, the difference between this embodiment and the static pressure gas radial bearing film pressure test method is that no air passage (such as an air supply hole) is opened inside the bearing sleeve 1 and the bearing bush 2, but an air supply passage is designed in the sealing cover. During calibration, high-pressure gas is supplied to the sealing chamber through the air supply passage of the sealing cover.

[0068] This invention also provides a more specific method and apparatus for testing the film pressure of hydrostatic gas thrust bearings, such as... Figure 3 As shown, it includes the following steps:

[0069] First, pre-process the patch: attach the strain gauge 3 to the back of the thrust bearing bush 2 corresponding to the thrust bearing pressure test position. The shielding wire is made of high temperature resistant and anti-interference material and is connected to the data acquisition module 4 through the bearing sleeve 1. Ensure proper insulation protection so as not to affect the normal operation of the equipment.

[0070] Next, system calibration is performed: a sealing end cap 6 is installed on the thrust bearing, forming a sealed chamber between the sealing end cap 6 and the bearing bush 2. High-pressure gas is supplied into the sealed chamber through the air supply hole of the bearing sleeve 1, applying a pressure of 0~1.0MPa, and the bridge output voltage Uy is collected. A calibration mathematical model is established between the air supply pressure P and the bridge output voltage Uy.

[0071] Then, an actual test was conducted: the sealing end cover 6 was removed, the bearing was put into working condition, the voltage signal output of the strain gauge 3 bridge was collected, and the rotational speed and temperature were recorded simultaneously.

[0072] Finally, pressure inversion: The real-time air film pressure signal is denoised and filtered using signal processing terminal 5, and then substituted into the calibration mathematical model for calculation to obtain the air film pressure of the bearing at that point.

[0073] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0074] 1. Non-destructive and high-fidelity testing: The bearing bush 2 is patched on the back, which does not damage the inner wall of the bearing bush 2, does not make holes, and does not invade the air film gap, thus completely preserving the original air film flow field. The test results are more in line with the actual working conditions of the bearing, and solve the problem of distortion in pressure measurement with holes.

[0075] 2. Low cost and easy to promote: It adopts conventional strain gauges and acquisition equipment, which are inexpensive, have a simple assembly process, require no professional debugging, and are suitable for laboratory research and development and batch testing in engineering fields.

[0076] 3. High versatility: It is compatible with various gas bearings such as radial bearings and thrust bearings. It can test static pressure distribution and capture high-speed dynamic pressure fluctuations. It can adapt to the testing needs of bearings of different specifications and working conditions without the need to design special devices for different types of bearings.

[0077] 4. Enables online real-time measurement: The strain gauge 3 can be pasted after the bearing is installed (or pasted before assembly without affecting the bearing installation). The test process does not require disassembling the bearing and can collect air film pressure data in real time, meeting the needs of online monitoring, fault diagnosis and performance evaluation at the engineering site.

[0078] This method can be flexibly adapted to radial bearings and thrust bearings: for radial bearings, strain gauges are arranged along the circumference and axial direction of the bearing bush to collect the gas film pressure and its distribution; for thrust bearings, strain gauges are arranged along the radial and circumference of the thrust plate to collect the gas film pressure distribution. There is no need to change the test device and core algorithm, making it highly versatile.

[0079] It should be understood that the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural. Additionally, the character " / " in this article generally indicates an "or" relationship between the preceding and following related objects, but it can also represent an "and / or" relationship. Please refer to the context for a more accurate understanding.

[0080] In this invention, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of a single item or a plurality of items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, and c can be a single item or multiple items.

[0081] It should be understood that, in various embodiments of the present invention, the order of the above-mentioned process numbers does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0082] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0083] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the devices, apparatuses, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0084] In the several embodiments provided by this invention, it should be understood that the disclosed devices, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0085] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0086] In addition, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0087] 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 variations or substitutions that can be easily conceived by those 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 determined by the scope of the claims.

Claims

1. A gas bearing film pressure testing device based on bearing bush micro-deformation, characterized in that, The testing apparatus includes: A gas bearing, comprising a rotor, a bearing bush, and a bearing sleeve disposed on the outside of the bearing bush, wherein the bearing bush is an integral structure and the inner surface is a complete surface, and a preset pressure test groove is provided; the gas film of the gas bearing is located on the side of the bearing bush closer to the rotating shaft. Multiple strain gauges are disposed on the side of the bearing bush in the preset pressure test groove away from the gas film. A data acquisition module, which is communicatively connected to the plurality of strain gauges, is used to acquire the strain signals of the plurality of strain gauges; A signal processing terminal is communicatively connected to the data acquisition module and is used to receive and process the strain signal.

2. The gas bearing film pressure testing device according to claim 1, characterized in that, The bearing bush has multiple preset pressure test grooves on the surface away from the gas film, and the multiple strain gauges are disposed in the multiple preset pressure test grooves.

3. The gas bearing film pressure testing device according to claim 2, characterized in that, The multiple strain gauges are arranged in an array and electrically connected to the data acquisition module via shielded wires; The multiple strain gauges are interconnected through a temperature drift compensation circuit, and the external parts of the multiple strain gauges are encapsulated with insulating and waterproof adhesive.

4. The gas bearing film pressure testing device according to claim 3, characterized in that, The plurality of strain gauges are uniaxial strain gauges, or the strain gauges are strain flowers.

5. The gas bearing film pressure testing device according to claim 4, characterized in that, The testing device also includes a calibration component. The calibration components include: A sealing end cap is provided, wherein the bearing sleeve and the sealing end cap together form a cavity, and the gas film of the gas bearing is located in the cavity; a sealing ring is provided between the bearing bush and the sealing end cap; A gas path pressure regulating module is connected to the cavity and is used to control the pressure of the gas film.

6. The gas bearing film pressure testing device according to claim 5, characterized in that, The testing apparatus also includes: Multiple air supply holes are provided on the bearing bush, and the air circuit pressure stabilizing module is connected to the cavity through the multiple air supply holes.

7. A method for testing the film pressure of a gas bearing based on the micro-deformation of the bearing bush, characterized in that, The testing method includes the following steps: S1. Multiple strain gauges are installed in multiple preset pressure test grooves of the gas bearing bush. The multiple strain gauges are connected to a data acquisition module, and the data acquisition module is connected to a signal processing terminal. The signal processing terminal includes a calibration model unit, a signal preprocessing unit, and a pressure inversion unit. The multiple preset pressure test grooves are installed on the surface of the bush away from the center of the gas bearing. S2. The bearing bush is placed under the test condition, and the data acquisition module receives the real-time gas film pressure signal of the multiple strain gauges when the gas bearing is working. S3. The signal preprocessing unit filters the real-time air film pressure signal to obtain the processed real-time air film pressure signal, and the pressure inversion unit obtains the real-time air film pressure value based on the real-time air film pressure signal and the mathematical model.

8. The gas bearing film pressure testing method according to claim 7, characterized in that, Before step S1, the following steps are also included: S4. Grind and degrease the bearing bush of the gas bearing; install multiple strain gauges in multiple preset pressure test grooves of the bearing bush; S5. The gas bearing is calibrated using a calibration component to establish a mathematical model relating the pressure signal and the gas pressure signal.

9. The gas bearing film pressure testing method according to claim 8, characterized in that, Step S5 includes: S51. The gas bearing is placed in the calibration assembly; wherein, the calibration assembly includes a sealing end cap, the sealing end cap and the bearing sleeve of the gas bearing together form a cavity; the calibration assembly also includes a gas path pressure stabilizing module, the gas path pressure stabilizing module is connected to the cavity; S52. When the bearing bush is a radial bearing bush, the air pressure stabilizing module applies gas pressure to the inner wall of the radial bearing bush; when the bearing bush is a thrust bearing thrust plate, the air pressure stabilizing module applies gas pressure to the pressure bearing surface of the thrust bearing thrust plate. S53. The data acquisition module receives the pressure signals output by the plurality of strain gauges and transmits them to the signal processing terminal. S54. The calibration model unit establishes a mathematical model relating the pressure signal and the gas pressure value, wherein the mathematical model is established using a linear fitting method.

10. The gas bearing film pressure testing method according to claim 9, characterized in that, In step S3: The filtering process includes first performing median filtering on the real-time air film pressure signal, and then performing low-pass filtering on the real-time air film pressure signal.

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