A bearing dynamic clearance measurement method based on resonance attenuation method and related device

Abstract

The application discloses a kind of bearing dynamic play measurement method and related device based on resonance attenuation method, comprising: by the way of electromagnetic loading, load bearing-main shaft system is carried out.By resonance attenuation method, attenuation response curve is obtained, based on transient time-frequency signal analysis method, instantaneous frequency and envelope amplitude are obtained, and then main curve is identified.Bearing quasi-static model is established, the mapping relationship between bearing play and time-varying stiffness fluctuation mean size and fluctuation range is obtained, the dynamic time-varying stiffness in the actual operation process of bearing system is tested multiple times, and then the internal dynamic play of bearing is effectively and accurately detected.The above process is realized by a set of test device, mainly including electromagnetic loading platform-hydraulic loading platform-measured bearing system-support main shaft system-driving system-measuring system 6 parts.The application is suitable for a plurality of different types of positive play rolling bearings, and is suitable for accurate measurement of bearing dynamic play.

Description

Technical Field

[0001] This invention belongs to the field of bearing condition measurement technology, and relates to a bearing dynamic clearance measurement method and related device based on resonance attenuation method. Background Technology

[0002] Clearance is a crucial structural parameter of a bearing. Appropriate clearance parameters significantly impact various bearing performance indicators, such as bearing life, frictional resistance, mechanical operating accuracy, temperature rise, noise, vibration, and reliability. Theoretical analysis and engineering research reveal that insufficient radial clearance can easily lead to problems like bearing overheating, reduced lubricant viscosity, and adhesive wear. Conversely, excessive radial clearance can exacerbate cage slippage, intensify impacts on the bearing's moving parts, and consequently cause pitting and component wear.

[0003] Most existing methods for measuring bearing clearance are static measurement methods that primarily measure radial clearance. For example, the national standard JB3573-2004T describes a simple method for measuring the radial clearance of roller bearings. However, during actual bearing operation, the bearing undergoes radial deformation, and the internal clearance changes in real time under the combined effects of assembly interference force, centrifugal inertial force, and thermal stress. Therefore, accurately measuring the dynamic clearance of bearings becomes increasingly important.

[0004] like Figure 1 As shown, rolling bearings typically undergo rotational motion in practical engineering applications. To avoid problems such as excessive friction and heat generation, the internal components of rolling bearings must have a certain clearance, known as clearance. Clearance is a crucial parameter in rolling bearings, and national standards specify the standard range for rolling bearing clearance. For bearings, if the clearance is too small, it will lead to increased friction and temperature rise, further affecting the bearing's lifespan. Conversely, if the clearance is too large, the bearing will not achieve the required rotational accuracy during operation, resulting in increased vibration and impact, which will also shorten the bearing's lifespan. Therefore, clearance is a critical parameter for the normal operation of a bearing. Based on the direction of movement, the internal clearance of a bearing can be divided into radial clearance and axial clearance.

[0005] like Figure 2 As shown, when a bearing is installed in a spindle system, its clearance will change. Simultaneously, during actual operation, the bearing's internal clearance is subjected to the coupled effects of assembly interference force, centrifugal inertial force, and thermal stress. This may cause radial expansion of the bearing, further altering its internal clearance.

[0006] Traditional bearing system analysis often simplifies the process, neglecting the impact of changes in the circumferential position of the bearing rollers on the bearing stiffness characteristics, i.e., ignoring the time-varying nature of bearing stiffness. For example... Figure 5 As shown, during the actual operation of a bearing, the number of rollers involved in bearing load-bearing changes periodically, i.e., the bearing load-bearing area changes. This causes significant time-varying fluctuations in bearing stiffness, resulting in time-varying nonlinear characteristics of bearing stiffness. For example... Figure 6 As shown, during one cycle of bearing roller position, the bearing stiffness exhibits significant fluctuations when the number of contact rollers increases or decreases. Summary of the Invention

[0007] The purpose of this invention is to solve the problems in the prior art and provide a bearing dynamic clearance measurement method and related device based on the resonance attenuation method. This method is used to study the evolution of the bearing internal clearance under actual working conditions with the installation and adjustment parameters and temperature during the actual operation of the bearing, to complete the analysis of the time-varying stiffness fluctuation behavior of the bearing, to measure the accurate dynamic clearance of the bearing, and to ensure the rotational accuracy of the bearing equipment.

[0008] To achieve the above objectives, the present invention employs the following technical solution:

[0009] In a first aspect, the present invention provides a method for measuring dynamic clearance of bearings based on the resonance attenuation method, comprising the following steps:

[0010] Excite the principal resonance response behavior of the test bearing-spindle system;

[0011] The decay response curve of the nonlinear system in the main resonance region is obtained, and the instantaneous frequency and envelope amplitude of the test bearing-spindle system are obtained by transient time-frequency signal analysis method, so as to obtain the main curve of the tested bearing-spindle system in the main resonance response range.

[0012] The main curve was analyzed and calculated using nonlinear modal analysis to obtain the mean value and fluctuation range of the time-varying stiffness of the tested bearing.

[0013] A quasi-static model of the bearing is established to obtain the mapping relationship between the mean value and fluctuation range of the time-varying stiffness of the bearing under test and its internal clearance, thereby completing the real-time detection of the bearing's internal clearance based on time-varying stiffness measurement.

[0014] Secondly, the present invention provides a bearing dynamic clearance measurement system based on the resonance attenuation method, comprising:

[0015] The corresponding behavior excitation module is used to excite the main resonant response behavior of the test bearing-spindle system.

[0016] The main curve calculation module is used to obtain the decay response curve of the nonlinear system within the main resonance region, and to obtain the instantaneous frequency and envelope amplitude of the tested bearing-spindle system through transient time-frequency signal analysis methods, thus obtaining the main curve of the tested bearing-spindle system within the main resonance response range.

[0017] The mean and fluctuation calculation module is used to analyze and calculate the main curve using nonlinear modal analysis methods to obtain the mean value and fluctuation range of the time-varying stiffness of the tested bearing.

[0018] The model building module is used to establish a quasi-static model of the bearing, obtain the mean value and fluctuation range of the time-varying stiffness of the bearing under test and the mapping relationship between it and its internal clearance, and complete the real-time detection of the bearing's internal clearance based on time-varying stiffness measurement.

[0019] Thirdly, the present invention provides a bearing dynamic clearance measurement device based on the resonance attenuation method, comprising:

[0020] A support base is provided, on which an electromagnetic loading device is installed; the spindle to be measured is mounted on the electromagnetic loading device; a front-end support ball bearing, a hydraulic loading device, and a rear-end support ball bearing are sleeved on the spindle; the spindle is connected to a motor via a coupling.

[0021] An electromagnetic loading device includes a cylindrical silicon steel sheet, on the side of which several stator cores are evenly arranged circumferentially, and each stator core is wound with a coil, the coil and the stator core forming an electromagnet; the coil is connected to a controller through a power amplifier, and several eddy current displacement sensors are also provided on the side of the spindle.

[0022] A hydraulic loading device is disposed on both sides of the electromagnetic loading device.

[0023] Fourthly, the present invention provides a computer device including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the method described above.

[0024] Fifthly, the present invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the method described above.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] This invention discloses a method and apparatus for measuring dynamic bearing clearance based on the resonance attenuation method. This invention considers that under real-world operating conditions, the number of rollers participating in bearing load-bearing changes periodically during bearing operation, resulting in significant periodic variations in bearing stiffness. The internal clearance of a bearing is crucial to its performance parameters such as lifespan and rotational accuracy. However, during actual bearing operation, the internal clearance changes in real time due to the combined effects of assembly interference force, centrifugal inertial force, and thermal stress. Furthermore, traditional bearing clearance measurement methods mostly focus on static measurements of radial clearance, rarely addressing dynamic clearance measurement. This invention employs the resonance attenuation method, which can extract the main curve of the bearing's nonlinear system, accurately obtain the frequency and amplitude of the bearing system, and calculate the accurate dynamic clearance based on the mapping relationship between clearance and resonant frequency.

[0027] Furthermore, the loading method of the spindle system of the present invention adopts non-contact electromagnetic loading to avoid inputting redundant information to the spindle system due to contact friction.

[0028] Furthermore, in the simulation calculation and analysis process of this invention, the influence of the change in the circumferential position of the bearing roller on the bearing stiffness characteristics is considered, and the time-varying characteristics of bearing stiffness are fully taken into account.

[0029] Furthermore, this invention employs the resonance decay method in nonlinear parameter identification methods to estimate instantaneous amplitude-frequency and damping from the decay response caused by steady-state oscillations. This can accurately identify the main curve of the bearing nonlinear system and accurately obtain the instantaneous frequency and amplitude in the bearing system.

[0030] Furthermore, the present invention establishes a certain mapping relationship between the internal clearance of the bearing and the time-varying stiffness of the bearing fluctuation, and the measured value has good consistency with the theoretical calculation value. A quasi-static model of the bearing is constructed, which can calculate the accurate dynamic clearance of the bearing. Attached Figure Description

[0031] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of the radial-axial clearance of the bearing.

[0033] Figure 2 This is a schematic diagram illustrating the effect of radial expansion on bearing clearance.

[0034] Figure 3This is a flowchart of the method of the present invention.

[0035] Figure 4 This is a schematic diagram of the system of the present invention.

[0036] Figure 5 This is a schematic diagram illustrating the periodic variation of the number of roller contacts with circumferential position.

[0037] Figure 6 This is a schematic diagram of the time-varying characteristics of bearing stiffness.

[0038] Figure 7 This is a technical roadmap for measuring dynamic clearance in bearings.

[0039] Figure 8 This is a schematic diagram of an implementation scheme for the resonance attenuation method.

[0040] Figure 9 This is a schematic diagram of the test platform for measuring the stress state of a bearing.

[0041] Figure 10 This is a schematic diagram of a non-contact electromagnetic loading device.

[0042] Figure 11 This is a circuit diagram of a non-contact electromagnetic loading device.

[0043] Among them: 1-motor, 2-spindle, 3-coupling, 4-front end support ball bearing, 5-hydraulic loading device, 6-rear end support ball bearing, 7-electromagnetic loading device, 8-coil, 9-eddy current displacement sensor, 10-support base, 11-silicon steel sheet, 12-electromagnet, 13-power amplifier, 14-controller. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0045] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0046] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0047] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationships commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation—or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first" or "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0048] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0049] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "setting," "installing," "connecting," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0050] The present invention will now be described in further detail with reference to the accompanying drawings:

[0051] See Figure 3 This invention discloses a method for measuring dynamic clearance of bearings based on the resonance attenuation method, comprising the following steps:

[0052] S1 excites the main resonant response behavior of the test bearing-spindle system by applying a load to the test bearing-spindle system through a non-contact electromagnetic loading method.

[0053] S2 obtains the decay response curve of the nonlinear system in the main resonance region, and obtains the instantaneous frequency and envelope amplitude of the test bearing-spindle system through transient time-frequency signal analysis method, thus obtaining the main curve of the tested bearing-spindle system in the main resonance response range.

[0054] The transient time-frequency signal analysis method includes the Hilbert transient time-frequency signal analysis method or the wavelet transform transient time-frequency signal analysis method.

[0055] The acquisition of the instantaneous frequency of the test bearing-spindle system includes:

[0056] The zero-crossing point of the response signal is detected, the crossover time is determined using the standard deviation algorithm, and a moving average filter is used to smooth the area around the crossover point. After determining the crossover time series, the estimated instantaneous frequency at the next moment of any crossover point is calculated, a moving average filter is constructed, and the final instantaneous frequency is calculated.

[0057]

[0058] Where f() represents the instantaneous frequency, This represents the crossover time, and N represents the order of the moving average filter. Indicates the instantaneous frequency at the intersection point. Let i represent any intersection point and j represent another intersection point.

[0059] The acquisition of the envelope amplitude of the test bearing-spindle system includes:

[0060] By tracking the signal peak within each individual zero-crossing time interval, the response envelope is extracted at each interval. The maximum absolute value of signal X and its corresponding occurrence time were retrieved within the timeframe.

[0061]

[0062]

[0063] in, Let X(t) represent the peak value of the signal, and X(t) represent the signal sequence. This represents the time interval. While calculating the instantaneous frequency, the instantaneous amplitude is estimated based on the interpolation function.

[0064] The backbone curve was obtained using the following method:

[0065] The main curve is a function of frequency and amplitude parameterized with time. The sequences A(t) and Γ(t) are paired accordingly:

[0066]

[0067] Where A() represents the instantaneous amplitude, and Γ(t) is the digital sequence. The polynomial interpolation function represents the envelope of the decay time signal.

[0068] S3 uses nonlinear modal analysis to analyze and calculate the main curve, obtaining the mean value and fluctuation range of the time-varying stiffness of the tested bearing.

[0069] S4 establishes a quasi-static model of the bearing, obtains the mapping relationship between the mean value and fluctuation range of the time-varying stiffness of the tested bearing and its internal clearance, and completes the real-time detection of the bearing's internal clearance based on time-varying stiffness measurement.

[0070] The process of obtaining the mapping relationship between the mean value and fluctuation range of the time-varying stiffness of the tested bearing and its internal clearance, and completing the real-time detection of the bearing's internal clearance based on time-varying stiffness measurement, includes:

[0071] Construct the five-degree-of-freedom mechanical equilibrium equations of the rotor and rewrite them in matrix form as follows:

[0072] F m =N1(d1)×F L +N2(d1)×F R

[0073] Where d1 is the distance between the rotor center and the bearing center, N1 and N2 are the transfer matrices, and F L and F R It is the elastic restoring force.

[0074] A multi-layered nested iterative algorithm is used to solve the above matrix equations, where the inner iterations calculate the mechanical equations of the local rolling elements of the bearing. After the internal rolling elements of the bearing complete one revolution with the cage, the bearing will experience a complete stiffness fluctuation cycle. At this time, the revolution angle of the internal rolling elements of the bearing is:

[0075]

[0076] The complete stiffness fluctuation curve of the bearing-rotor system within a single cycle can be obtained by changing the magnitude of the rolling element revolution angle; that is, the revolution angle within the rolling element revolution angle... Uniformly select values ​​within the interval:

[0077]

[0078] Where Z is the number of rolling elements, and N is the number of rolling elements. b This refers to the number of points taken within a single stiffness fluctuation period.

[0079] Using a coupled frequency sweep analysis method, the following results were obtained: Y-axis accelerated frequency sweep response, Z-axis accelerated frequency sweep response, Y-axis deceleration frequency sweep response, and Z-axis deceleration frequency sweep response. This established the mapping relationship between bearing clearance and time-varying stiffness, and subsequently, the dynamic clearance was calculated.

[0080] δ(t)=F[ψ(t)]

[0081] Where δ(t) is the dynamic clearance of the bearing.

[0082] like Figure 4 As shown, this embodiment of the invention discloses a bearing dynamic clearance measurement system based on the resonance attenuation method, comprising:

[0083] The corresponding behavior excitation module is used to excite the main resonant response behavior of the test bearing-spindle system.

[0084] The main curve calculation module is used to obtain the decay response curve of the nonlinear system within the main resonance region, and to obtain the instantaneous frequency and envelope amplitude of the tested bearing-spindle system through transient time-frequency signal analysis methods, thus obtaining the main curve of the tested bearing-spindle system within the main resonance response range.

[0085] The mean and fluctuation calculation module is used to analyze and calculate the main curve using nonlinear modal analysis methods to obtain the mean value and fluctuation range of the time-varying stiffness of the tested bearing.

[0086] The model building module is used to establish a quasi-static model of the bearing, obtain the mapping relationship between the mean value and fluctuation range of the time-varying stiffness of the bearing under test and its internal clearance, and complete the real-time detection of the bearing's internal clearance based on time-varying stiffness measurement.

[0087] The principle of this invention:

[0088] like Figure 7 The diagram illustrates the overall technical roadmap of this invention. On one hand, through parametric resonance response research, a nonlinear parameter identification method is used to obtain the attenuation curve within the parametric resonance region. Hilbert or wavelet transform is used to identify the main curve of the tested bearing-spindle system. Nonlinear modal analysis is then used to calculate the mean magnitude and fluctuation range of the time-varying stiffness of the tested bearing. On the other hand, through bearing time-varying stiffness fluctuation analysis, a quasi-static model of the bearing is established to obtain the mapping relationship between stiffness fluctuation and internal clearance. Finally, based on this mapping relationship, the accurate internal dynamic clearance of the bearing is calculated, enabling real-time detection of bearing clearance. Simultaneously, this invention also constructs a measuring device for the internal dynamic clearance of the bearing, which comprises six parts: an electromagnetic loading platform, a hydraulic loading platform, the tested bearing system, a supporting spindle system, a drive system, and a measuring system.

[0089] like Figure 8 As shown, Figure 8This is an implementation plan for studying the parametric resonance response identification of a bearing-spindle system based on the resonance attenuation method. First, the attenuation response needs to be obtained. Based on the resonance attenuation method (RDM) in nonlinear parameter identification methods, the normal force mode assignment method is used to calculate appropriate system modes. Then, harmonic excitation is used to activate the nonlinearity of the system structure, generating attenuation response curves within the parametric resonance region.

[0090] The instantaneous frequency and envelope amplitude of the bearing-spindle system under test are obtained by using transient time-frequency signal analysis methods such as Hilbert or wavelet transform.

[0091] Obtaining the instantaneous frequency: Detect the zero-crossing points of the response signal and use the standard deviation algorithm to determine the crossover time. Smooth the area around the crossover point using a suitable moving average filter. Once the crossover time series is determined, the estimated instantaneous frequency at the next time step of any crossover point can be calculated. A moving average filter is constructed to calculate the final instantaneous frequency, defined as follows:

[0092]

[0093] Moving average filters effectively reduce random noise while maintaining a clear step response. The filter order is selected based on the noise level present in the signal.

[0094] Obtaining Instantaneous Amplitude: The instantaneous amplitude of the decaying response is obtained by extracting the response envelope by tracking the signal peak value within each individual zero-crossing time interval. In each interval... The maximum absolute value of signal X and its corresponding occurrence time were retrieved within the timeframe. Equation of use:

[0095]

[0096]

[0097] Let Γ(t) be defined as a number sequence The polynomial interpolation function defines the envelope of the decaying time signal. The instantaneous amplitude is estimated simultaneously with the calculation of the instantaneous frequency using the interpolation function.

[0098]

[0099] The trunk curve, as a function of frequency and amplitude parameterized over time, can be used to pair sequences A(t) and f(t) to obtain the trunk curve.

[0100] Calculating internal clearance: Based on the amplitude-frequency response curve of the nonlinear system, a quasi-static model of the bearing is established to obtain the mapping relationship between the mean magnitude and range of stiffness fluctuations of the tested bearing and its internal clearance. Based on the mapping relationship between bearing clearance and time-varying bearing stiffness, the dynamic clearance of the bearing is calculated, enabling real-time detection of changes in the bearing's internal clearance.

[0101] like Figure 9 As shown, this embodiment of the invention discloses a bearing dynamic clearance measuring device based on the resonance attenuation method, including a support base 10, an electromagnetic loading device 7, and a hydraulic loading device 5.

[0102] An electromagnetic loading device 7 is installed on the support base 10; the spindle 2 to be measured is mounted on the electromagnetic loading device 7; a front support ball bearing 4, a hydraulic loading device 5, and a rear support ball bearing 6 are sleeved on the spindle 2, with the hydraulic loading device located on both sides of the electromagnetic loading device 7. The spindle 2 is connected to the motor 1 via a coupling 3.

[0103] like Figure 10 As shown, the electromagnetic loading device 7 includes a cylindrical silicon steel sheet 11. Several stator cores are evenly arranged on the side of the silicon steel sheet 11 along the circumference. A coil 8 is wound on each stator core. The coil 8 and the stator core constitute an electromagnet 12.

[0104] like Figure 11 As shown, Figure 11 This is a circuit diagram of a non-contact electromagnetic loading device. The coil 8 is connected to the controller 14 through the power amplifier 13, and several eddy current displacement sensors 9 are also provided on the side of the main shaft 2.

[0105] Working principle of the measuring device of this invention:

[0106] Electromagnetic loading is a non-contact loading method. The loading frequency and load can be controlled via an external controller, thereby stimulating the resonant response behavior of the tested bearing-spindle system. The electromagnetic loading platform includes an embedded eddy current displacement sensor and coil, and the software system includes a controller. Its schematic diagram and circuit diagram are shown below. Figure 10 and Figure 11 As shown. The electromagnetic loading device is similar in structure to an electromagnetic bearing. Its main structure includes silicon steel sheets, a stator core, and coils wound around the stator core. The coils on each pair of adjacent magnetic poles are connected in series to form a magnetic pole pair. When current flows through the coils, a closed magnetic circuit is generated between the silicon steel sheets, the stator core, and the air gap, thereby generating electromagnetic force. The electromagnetic loading platform mainly operates on the spindle.

[0107] Hydraulic loading: A hydraulic loading platform is used to apply radial static loading to the bearing under test, simulating the stress state of the bearing under actual operation. The hydraulic loading platform mainly acts on the outer ring of the bearing.

[0108] The bearing system under test: rolling bearings such as deep groove ball bearings and cylindrical roller bearings that have positive clearance under working conditions. Figure 9 In the dynamic clearance measurement device for bearings, a ball bearing is used as a demonstration example.

[0109] Support spindle system: A high-rigidity spindle system with back-to-back symmetrical design, with support structures installed at both ends.

[0110] Drive system: A motor is arranged in the device, and a high-speed electric spindle is installed. It is connected to the bearing-spindle system under test through a flexible coupling and drives it.

[0111] Measurement system: It performs parametric resonance response identification, realizes the analysis of bearing time-varying stiffness fluctuation and parametric resonance response based on the force-thermal coupling analysis model of multi-field-multi-degree-of-freedom rolling bearing, and feeds the measurement data back to the terminal equipment in real time.

[0112] A computer device is provided according to an embodiment of the present invention. This computer device includes a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps in the various method embodiments described above. Alternatively, when the processor executes the computer program, it implements the functions of each module / unit in the various device embodiments described above.

[0113] The computer program can be divided into one or more modules / units, which are stored in the memory and executed by the processor to complete the present invention.

[0114] The computer device may be a desktop computer, laptop, handheld computer, or cloud server, etc. The computer device may include, but is not limited to, a processor and memory.

[0115] The processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc.

[0116] The memory can be used to store the computer program and / or module, and the processor implements various functions of the computer device by running or executing the computer program and / or module stored in the memory, and by calling the data stored in the memory.

[0117] If the modules / units integrated into the computer device are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in the computer-readable medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electrical carrier signals and telecommunication signals.

[0118] The above are merely preferred embodiments of the present invention and are not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for measuring dynamic clearance of bearings based on the resonance attenuation method, characterized in that, Includes the following steps: Excite the principal resonance response behavior of the test bearing-spindle system; The decay response curve of the nonlinear system in the main resonance region is obtained, and the instantaneous frequency and envelope amplitude of the test bearing-spindle system are obtained by transient time-frequency signal analysis method, so as to obtain the main curve of the tested bearing-spindle system in the main resonance response range. The main curve was analyzed and calculated using nonlinear modal analysis to obtain the mean value and fluctuation range of the time-varying stiffness of the tested bearing. A quasi-static model of the bearing is established to obtain the mapping relationship between the mean value and fluctuation range of the time-varying stiffness of the bearing under test and its internal clearance. Real-time detection of the bearing's internal clearance based on time-varying stiffness measurement is then achieved. The specific method is as follows: The five-degree-of-freedom mechanical equilibrium equations of the rotor are constructed, and their matrix form is as follows: in, The vector of the external force acting on the rotor center. This is the distance between the rotor center and the bearing center. and These are the transfer matrices for the left and right sides, respectively. and These represent the elastic restoring forces on the left and right sides, respectively. A multi-layered nested iterative algorithm is used to solve the above matrix equations, where the inner iterations calculate the mechanical equations of the local rolling elements of the bearing. After the internal rolling elements of the bearing complete one revolution with the cage, the bearing will experience a complete stiffness fluctuation cycle; at this time, the revolution angle of the internal rolling elements of the bearing is... for: in, This represents the number of rolling elements; The complete stiffness fluctuation curve of the bearing-rotor system within a single cycle is obtained by changing the magnitude of the rolling element revolution angle, i.e., the revolution angle within the rolling element revolution angle. Uniformly select values ​​within the interval: in, This refers to the revolution angle of the rolling elements inside the bearing. This refers to the number of points taken within a single stiffness fluctuation period. This refers to the stiffness fluctuation period experienced by the bearing. Using a coupled frequency sweep analysis method, the following results were obtained: Y-axis accelerated frequency sweep response, Z-axis accelerated frequency sweep response, Y-axis deceleration frequency sweep response, and Z-axis deceleration frequency sweep response. This established a mapping relationship between bearing clearance and time-varying stiffness, allowing for the calculation of the bearing dynamic clearance. : in, This represents the mapping relationship between bearing clearance and time-varying stiffness. This is the complete stiffness fluctuation curve of the bearing within a single cycle.

2. The bearing dynamic clearance measurement method based on resonance attenuation method according to claim 1, characterized in that, The main resonance response behavior of the test bearing-spindle system is excited by applying a load to the test bearing-spindle system through non-contact electromagnetic loading; the transient time-frequency signal analysis method includes Hilbert transient time-frequency signal analysis method or wavelet transform transient time-frequency signal analysis method.

3. The bearing dynamic clearance measurement method based on resonance attenuation method according to claim 1 or 2, characterized in that, The acquisition of the instantaneous frequency of the test bearing-spindle system includes: The zero-crossing point of the response signal is detected, the crossover time is determined using the standard deviation algorithm, and a moving average filter is used to smooth the area around the crossover point. After determining the crossover time series, the estimated instantaneous frequency at the next moment of any crossover point is calculated, a moving average filter is constructed, and the final instantaneous frequency is calculated. in, Indicates instantaneous frequency. Indicates the crossover time. This indicates the order of the moving average filter. Indicates the instantaneous frequency at the intersection point. Indicates another crossover time, i Indicates any intersection point, j This indicates another intersection point.

4. The bearing dynamic clearance measurement method based on resonance attenuation method according to claim 1 or 2, characterized in that, The acquisition of the envelope amplitude of the test bearing-spindle system includes: By tracking the signal peak within each individual zero-crossing time interval, the response envelope is extracted at each interval. The maximum absolute value of signal X and its corresponding occurrence time were retrieved within the timeframe. : in, Indicates the signal peak value. Represents a signal sequence. This represents the time interval. While calculating the instantaneous frequency, the instantaneous amplitude is estimated based on the interpolation function.

5. The bearing dynamic clearance measurement method based on resonance attenuation method according to claim 1 or 2, characterized in that, The backbone curve was obtained using the following method: The backbone curve is a function of frequency and amplitude parameterized with time, representing the sequence. A ( t )and Corresponding pairings: in, Indicates instantaneous amplitude. For number sequences The polynomial interpolation function represents the envelope of the decay time signal.

6. A bearing dynamic clearance measurement system based on the resonance attenuation method for implementing the method of claim 1, characterized in that, include: The corresponding behavior excitation module is used to excite the main resonant response behavior of the test bearing-spindle system. The main curve calculation module is used to obtain the decay response curve of the nonlinear system within the main resonance region, and to obtain the instantaneous frequency and envelope amplitude of the tested bearing-spindle system through transient time-frequency signal analysis methods, thus obtaining the main curve of the tested bearing-spindle system within the main resonance response range. The mean and fluctuation calculation module is used to analyze and calculate the main curve using nonlinear modal analysis methods to obtain the mean value and fluctuation range of the time-varying stiffness of the tested bearing. The model building module is used to establish a quasi-static model of the bearing, obtain the mean value and fluctuation range of the time-varying stiffness of the bearing under test and the mapping relationship between it and its internal clearance, and complete the real-time detection of the bearing's internal clearance based on time-varying stiffness measurement.

7. A bearing dynamic clearance measuring device based on the resonance attenuation method for implementing the method described in any one of claims 1-5, characterized in that, include: Support base (10), on which an electromagnetic loading device (7) is provided; the spindle (2) to be measured is set on the electromagnetic loading device (7); the spindle (2) is fitted with a front end support ball bearing (4), a hydraulic loading device (5) and a rear end support ball bearing (6); the spindle (2) is connected to the motor (1) through a coupling (3); The electromagnetic loading device (7) includes a cylindrical silicon steel sheet (11). Several stator cores are evenly arranged on the side of the silicon steel sheet (11) along the circumference. A coil (8) is wound on each stator core. The coil (8) and the stator core constitute an electromagnet (12). The coil (8) is connected to a controller (14) through a power amplifier (13). Several eddy current displacement sensors (9) are also provided on the side of the main shaft (2). A hydraulic loading device is provided on both sides of the electromagnetic loading device (7).

8. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method as described in any one of claims 1-5.

9. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as described in any one of claims 1-5.

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