An adaptive fast gear meshing detection method and device

Abstract

The application discloses a kind of self-adapting fast gear mesh detection method and device, it is related to detection technical field, wherein method includes: step S1 to S5, by gradually increasing loading strategy, gear pair is actively pushed from elastic deformation area to elastic-plastic area, the vibration data of each torque level is continuously collected, the change rate between adjacent levels is calculated to identify mutation point, and the real strength performance of gear under overload condition is fully exposed;While extracting vibration root mean square value, pulse factor, kurtosis and mesh frequency amplitude and other multi-characteristic parameters, combined with the characteristic value under the rated torque of mutation torque, determine the engagement strength qualified, critical or unqualified.The device includes base, pitch adjusting mechanism, pre-tightening mechanism, load brake, standard gear, servo motor, encoder and vibration sensor.The application can effectively distinguish gear eccentricity and insufficient strength by grading loading and multi-characteristic fusion, with high detection accuracy, fast speed, and the ability of self-adapting dynamic updating standard library.

Description

Technical Field

[0001] This invention relates to the field of testing, and in particular to an adaptive rapid gear meshing testing method and apparatus. Background Technology

[0002] Gear transmission is one of the most common forms of mechanical transmission. Its meshing quality (generally referring to the influencing factors in the gear pair meshing transmission process) directly affects the vibration, noise, lifespan, and safety of the entire machine. Traditional gear inspection methods are mainly divided into two categories: one is geometric accuracy inspection (such as tooth profile, tooth direction, and tooth pitch deviation measurement), which usually uses a coordinate measuring machine or gear measuring center. This method is slow, costly, and cannot reflect the actual meshing state. The other is dynamic meshing inspection, such as using a single-sided meshing instrument to measure transmission error or using a gear runout meter to detect the radial runout of the gear ring. However, existing dynamic inspection methods have the following problems:

[0003] First, the runout detector can only reflect the geometric eccentricity of the gear and the radial runout of the gear ring. It cannot distinguish between the vibration caused by eccentricity and the impact caused by insufficient tooth surface strength, which can easily lead to misjudgment.

[0004] Second, most tests are only performed under no-load or single-load conditions, which cannot obtain the complete response process of the gear from elastic deformation to elastoplastic failure.

[0005] Third, it is impossible to pinpoint the fault caused by damage (pitting, peeling) to the gear under test, making it difficult to achieve precise fault type identification. Summary of the Invention

[0006] To address the above problems, the present invention adopts the following technical solution.

[0007] An adaptive fast gear meshing detection method includes the following steps: S1: Install the gear to be tested on the testing device, mesh the gear to be tested with the standard gear and apply a preload, start the standard gear to rotate, and obtain the reference signal V0; S2: Outputs progressively increasing braking torque commands to the load brake, setting the rated torque TN; simultaneously drives the standard gear to rotate at a constant speed, and after each torque level stabilizes, collects the real-time rotation angle θ of the standard gear, and synchronously collects the vibration signal VI. S3: Perform order tracking on the vibration signal VI and real-time rotation angle θ at each torque level, extract vibration feature parameters and construct a vibration feature vector. The vibration feature parameters include at least the root mean square value of vibration, the amplitude of meshing frequency, the impulse factor and the vibration kurtosis. S4: Based on the parameters of the gear under test, automatically match the corresponding vibration characteristic standard range in the database, calculate the rate of change of the root mean square value of vibration or the impulse factor under two adjacent torque levels, and when the rate of change exceeds the set threshold, record the current torque value as the sudden torque and judge the meshing strength according to the judgment rules. S5: Outputs a comprehensive rating and fault type indication, and generates a traceable inspection report.

[0008] Preferably, in step S1, the preload is achieved by controlling the spring compression by adjusting the rotation angle of the adjustment handle. The preload range is 5-40N, and it is automatically matched according to the module of the gear to be tested, so that the tooth surface of the gear to be tested and the standard gear maintains a backlash-free contact and does not generate static friction. In step S2, the load brake is a magnetic powder brake or an eddy current brake, which is coaxially connected to the first push rod of the gear to be tested, and the loading accuracy is controlled by a torque sensor in a closed loop, with a deviation not exceeding ±1%.

[0009] Preferably, in step S3, the order tracking step includes: S300: Calculate the position of the gear under test at each sampling moment based on the real-time rotation angle θ output by the encoder; S301: Resample the vibration signal VI at equal angular intervals, using the fixed number of angle points for each tooth ring as the target, and convert the original non-uniform time series into a uniform angle series; S302: Perform a fast Fourier transform on the resampled angle domain signal to obtain the spectrum with the order as the abscissa. The order corresponding to the meshing frequency is equal to the number of teeth of the gear under test, and the order corresponding to each harmonic of the meshing frequency is an integer multiple of the number of teeth of the gear under test. S303: Directly calculates the root mean square value of vibration, impulse factor and vibration kurtosis based on the angle domain signal, and extracts the meshing frequency and vibration amplitude at the harmonic frequency based on the order spectrum.

[0010] Preferably, the determination rule in step S4 is as follows: If the sudden change torque is ≥120%TN, and the root mean square value of vibration under the rated torque TN is ≤ the allowable value, and the vibration kurtosis is ≤4, then the meshing strength is deemed qualified. If the sudden torque is between 100% and 120% of TN, and the vibration amplitude of the meshing frequency and its harmonics under the rated torque TN is ≥ twice the standard value, it is determined that there is eccentricity of the gear under test and the meshing strength has reached the critical point. If the sudden torque is less than 100% TN, or the pulse factor under the rated torque TN is greater than the allowable value, or the vibration kurtosis is greater than 5, then the meshing strength is deemed unqualified.

[0011] Preferably, the vibration characteristic standard range in step S4 adopts a dynamic update strategy. After testing a predetermined number of qualified gears of the same model, the new test data is included in the standard library, and the threshold range is automatically corrected.

[0012] Preferably, the present invention also provides an adaptive rapid gear meshing detection device for the aforementioned adaptive rapid gear meshing detection method, comprising a base, a support frame, a drive frame, and a controller mounted on the base, and a swing frame movably mounted on the support frame. The swing frame includes a first rotating shaft and a set of swing arms mounted on the first rotating shaft. A spacing adjustment mechanism is also mounted on the two swing arms, which is used to adjust the spacing between a first push rod and a second push rod. A pre-tightening mechanism is also fitted at the front end of the two swing arms, and the spacing adjustment mechanism cooperates with one end of the pre-tightening mechanism. A gear to be tested is also fitted between the pre-tightening mechanisms. A standard gear is mounted on the drive frame, and one side of the drive frame is also fitted with a servo motor via a transmission component. An encoder is also provided on the rotating shaft of the drive frame. The gear to be tested is located above the standard gear and meshes with it. A vertical column is also vertically mounted on the base, and a vibration sensor is movably mounted on the column. The bottom of the vibration sensor is in contact with a flat plate on the first rotating shaft.

[0013] Preferably, the spacing adjustment mechanism includes a connecting bushing, which is horizontally and vertically connected to two swing arms. An adjusting shaft is installed inside the connecting bushing, and a connecting plate is fixedly installed at the other end of the adjusting shaft. A pre-tightening mechanism is also installed at the other end of the connecting plate.

[0014] Preferably, the pre-tightening mechanism includes an adjusting handle, which is movably mounted on the outside of the connecting plate. The front ends of the two swing arms are respectively provided with a first push rod and a second push rod. The first push rod and the second push rod are used to install the gear to be tested. The first push rod also cooperates with a load brake, which is installed on the inside of one of the swing arms. The distal end of the second push rod also passes through the connecting plate and cooperates with the adjusting handle. The inside of the connecting plate is close to the swing arm, and a spring is fixedly installed between them. The spring is also fitted onto the second push rod.

[0015] Preferably, the vibration sensor is a piezoelectric accelerometer, and a coupling agent is coated between its bottom and the plate on the first rotating shaft.

[0016] Preferably, the load brake is a magnetic powder brake, with its stator fixed to the inside of the swing arm and its rotor coaxially connected to the first push rod. The braking torque is adjusted by the analog current output by the controller.

[0017] The beneficial effects of this invention are as follows: First, by simultaneously monitoring the root mean square value of vibration, impulse factor, vibration kurtosis and meshing frequency amplitude, and combining the sudden torque obtained by graded loading, this invention can clearly distinguish three failure modes: geometric eccentricity, tooth surface impact and insufficient material strength. Compared with the traditional single-parameter method, the detection accuracy is higher.

[0018] Secondly, this invention employs a progressively increasing load strategy from 10% to 120% of the rated torque, actively pushing the gear pair from the elastic deformation zone to the elastoplastic / failure zone. During the loading process, vibration data for each torque level is continuously collected, and abrupt change points are identified by calculating the rate of change between adjacent levels. This active excitation method can fully expose the true strength performance of the gear under overload conditions, and is particularly suitable for detecting hidden defects such as insufficient tooth surface contact fatigue strength and insufficient tooth root bending strength.

[0019] Third, this invention incorporates a pre-installed database in the controller, which automatically matches the corresponding standard range based on the module, tooth width, and material grade of the gear being tested. This standard library employs a dynamic update strategy: after testing a predetermined number (e.g., 100) of qualified gears of the same model, the system adds the new test data to the standard library and automatically corrects thresholds such as the allowable root mean square value of vibration, allowable impulse factor, and standard value of meshing frequency amplitude. This mechanism effectively eliminates the impact of zero-point drift of the sensor after long-term use, changes in ambient temperature, and wear of the mechanical structure on the detection accuracy, ensuring stable detection performance of the equipment during long-term operation.

[0020] Fourth, the device of this invention includes a base, a spacing adjustment mechanism, a pre-tightening mechanism, a load brake, a standard gear, a servo motor, an encoder, and a vibration sensor. Through graded loading and multi-feature fusion, it can effectively distinguish between gear eccentricity and insufficient strength, achieving high detection accuracy and speed, and possessing the ability to adaptively and dynamically update the standard library. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the method flow of the present invention; Figure 2 This is a schematic diagram of the method logic of the present invention; Figure 3 This is a three-dimensional structural schematic diagram of the device of the present invention; Figure 4 This is a top view of the device of the present invention; Figure 5 This is a front view schematic diagram of the device of the present invention; Figure 6 for Figure 4 Schematic diagram of the cross-sectional structure along line AA; In the figure: base 1, support frame 2, drive frame 3, controller 4, swing frame 5, first rotating shaft 50, swing arm 51, plate 52, spacing adjustment mechanism 6, pre-tightening mechanism 7, gear to be tested 8, standard gear 9, transmission component 10, servo motor 11, encoder 12, upright 13, vibration sensor 14, connecting bushing 60, adjusting shaft 61, connecting plate 62, adjusting handle 70, first push rod 71, second push rod 72, spring 73 and load brake 15. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0023] In the description of this invention, it should be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this 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. Therefore, they should not be construed as limitations on this invention. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0024] Example 1: Please see Figure 1-2 Before testing, the basic test object parameters need to be set: Gear 8 to be tested: Module m=2.5, Number of teeth z=30, Tooth width b=20mm, Material is 20CrMnTi.

[0025] Standard gear 9: Module m=2.5, number of teeth z=30, tooth width b=20mm, accuracy grade 5, rated torque is calculated according to the gear strength formula TN=120N·m.

[0026] The preload force F is set to 20N, the constant speed of the servo motor 11 is set to n=20rpm, the sampling frequency of the vibration sensor 14 is f=5000Hz, and the resolution of the encoder 12 is P=1024 pulses / revolution.

[0027] The following provides a detailed description of this application: an adaptive fast gear meshing detection method, comprising the following steps: S1: Install the gear 8 to be tested on the testing device, make the gear 8 to be tested mesh with the standard gear 9 and apply a preload, start the standard gear 9 to rotate, and obtain the reference signal V0; S2: Output a gradually increasing braking torque command to the load brake 15 and set the rated torque TN; at the same time, drive the standard gear 9 to rotate at a constant speed. After each torque level stabilizes, collect the real-time rotation angle θ of the standard gear 9 and collect the vibration signal VI simultaneously. S3: Perform order tracking on the vibration signal VI and real-time rotation angle θ at each torque level, extract vibration feature parameters and construct a vibration feature vector. The vibration feature parameters include at least the root mean square value of vibration, the amplitude of meshing frequency, the impulse factor and the vibration kurtosis. S4: Based on the parameters of the gear under test, automatically match the corresponding vibration characteristic standard range in the database, calculate the rate of change of the root mean square value of vibration or the impulse factor under two adjacent torque levels, and when the rate of change exceeds the set threshold, record the current torque value as the sudden torque and judge the meshing strength according to the judgment rules. S5: Outputs a comprehensive rating and fault type indication, and generates a traceable inspection report.

[0028] Specifically, S1 is implemented in the following way: The distance between the first push rod 71 and the second push rod 72 is adjusted by the distance adjustment mechanism 6. The gear 8 to be tested is installed between the first push rod 71 and the second push rod 72 to ensure that the gear 8 to be tested meshes with the standard gear 9. The adjustment handle 70 is rotated to apply a preload force to the gear 8 to be tested through the second push rod 72, and the standard gear 9 is started to rotate. The no-load signal collected by the vibration sensor 14 is acquired, filtered, and stored as a reference signal V0. The distance between the first push rod 71 and the second push rod 72 is adjusted by the distance adjustment mechanism 6. The gear 8 to be tested is installed between the first push rod 71 and the second push rod 72 to ensure that the gear 8 to be tested meshes with the standard gear 9. Rotating the adjustment handle 70 pushes the second push rod 72 through the thread, compressing the spring 73 and applying an axial preload to the gear 8 under test. The magnitude of the preload is determined by the spring stiffness and compression amount. In this embodiment, the module is automatically matched to F=20N. The servo motor 11 is started to drive the standard gear 9 to rotate at n=10rpm under no-load. The vibration sensor 14 collects the no-load vibration signal, filters it, and stores it as a reference signal V0 in the controller 4. This reference signal V0 is used for background subtraction of the signals collected by each load level in the subsequent process to eliminate the influence of the inherent vibration of the installation structure.

[0029] S2 is achieved as follows: the controller 4 outputs progressively increasing braking torque commands to the load brake 15, setting the rated torque TN; simultaneously, the servo motor 11 drives the standard gear 9 to rotate at a constant speed. After each torque level stabilizes, the encoder 12 collects the real-time rotation angle θ of the standard gear 9, and simultaneously collects the vibration signal VI from the vibration sensor 14; in this embodiment, a magnetic powder brake is selected, with a rated torque TN = 120 N·m and a loading step of 10%, specifically 10% TN = 12 N·m, 20% TN = 24 N·m, 30% TN = 36 N·m, and so on, until 1 At the end of 20%TN, the servo motor 11 drives the standard gear 9 to rotate at a constant speed of n=20rpm. The servo motor 11 automatically increases the output torque to overcome the resistance torque generated by the load brake 15. Each torque level runs stably for 3 complete gear rings, which takes t=9s. After stabilization, the encoder 12 collects the real-time rotation angle θ of the standard gear 9. At the same time, the vibration sensor 14 collects the vibration signal VI at f=5000Hz. In this way, each torque level obtains a total of 5000×9=45000 time domain data points and the corresponding angle sequence. In this embodiment, 12 sets of angle-vibration data can be obtained.

[0030] S3 is achieved by: performing order tracking on the vibration signal VI and real-time rotation angle θ at each torque level, and extracting vibration feature parameters. The purpose of order tracking is to eliminate the influence of small speed fluctuations on vibration analysis, so that feature extraction is independent of speed. The extracted feature parameters are combined to form a vibration feature vector, which includes the root mean square value of vibration, meshing frequency, vibration amplitude, impulse factor and vibration kurtosis. S4 achieves this by automatically matching the vibration characteristic standard range in the database based on the module, tooth width, and material grade of the gear under test, calculating the rate of change of the root mean square value or impulse factor of vibration under two adjacent torque levels, and recording the current torque value as a sudden change torque when the rate of change exceeds the set threshold, and making a judgment according to the judgment rules. S5 achieves this by automatically outputting a comprehensive rating and fault type prompts, displaying the characteristic curves of vibration root mean square value and impulse factor changes with torque, marking the location of sudden torque changes on the curves, encrypting and storing all original vibration waveforms and vibration feature vectors, binding them to the IDs of the testing equipment and the gear under test 8, and generating a traceable testing report.

[0031] Specifically: The detector automatically outputs the following content: Overall rating: Displayed as "critical" with a yellow warning color.

[0032] Fault type prompt: The text prompt "Eccentricity of gear 8 under test detected. Please correct the installation or replace the gear" is displayed, and the user is advised to check the coaxiality of the installation of gear 8 under test or re-align it.

[0033] Characteristic curves: Two curves are plotted on the display screen, representing the root mean square value of the vibration. The curves show the relationship between torque and impulse factor I, and the curves showing the relationship between torque and impulse factor I. The horizontal axis represents torque (unit: N·m), and the vertical axes represent the following values: (Unit: m / s²) and I. The locations on the graph are marked with red arrows and accompanied by the text "Sudden Torque".

[0034] Data encryption storage: All original vibration waveform data (3 gears per torque level, 12 torque levels in total), vibration feature vectors (each group contains...) 、I、A 1X The parameters (K and corresponding torque value), the serial number of the detection device, and the ID of the gear 8 to be tested (e.g., "G-2405-001" entered by the user) are processed by the AES-128 encryption algorithm, stored in the local SD card of the controller 4, and simultaneously uploaded to the cloud server via the WiFi module.

[0035] Test Report Generation: Automatically generates a PDF test report, including: test conditions (gear parameters, rated torque, test date), characteristic curves, sudden torque annotations, judgment results, and operational recommendations. The report can be viewed and downloaded online for easy quality traceability.

[0036] In some preferred embodiments, in step S1, the preload is achieved by controlling the compression of spring 73 by adjusting the rotation angle of the adjusting handle 70. The preload range is 5-40 N, and it is automatically matched according to the module of the gear 8 to be tested, so that the tooth surface of the gear 8 to be tested and the standard gear 9 maintains a backlash-free contact and does not generate static friction. In step S2, the load brake 15 is a magnetic powder brake or an eddy current brake, which is coaxially connected to the first push rod 71 of the gear 8 to be tested, and the loading accuracy is controlled by a torque sensor in a closed loop, with a deviation not exceeding ±1%.

[0037] In some preferred embodiments, step S3, the order tracking step includes: S300: Calculate the rotation angle position of the gear 8 under test at each sampling moment based on the real-time rotation angle θ output by encoder 12; For example: Encoder 12 outputs P=1024 pulses / revolution per revolution, and the angle increment corresponding to each pulse is 2π / P≈0.0061rad. For the i-th sampling point, the cumulative number of pulses is denoted as ci (a dimensionless integer). Then the gear rotation angle at the sampling time is θr=ci×(2π / P). S301: Resample the vibration signal VI at equal angular intervals, using the fixed number of angle points for each tooth ring as the target, and use a linear interpolation algorithm to convert the original non-uniform time series into a uniform angle series. Assuming each gear under test (8) is fixed at Q = 1024 angular sampling points, i.e., the equal angular interval = 2π / Q, the original time-domain vibration signal VI is then mapped to an equal angular sequence, specifically: A linear interpolation algorithm is used, and each target angle is denoted as θ. k Find two adjacent angles θ in the original data. i-1 θ i+1 The corresponding amplitude is denoted as: V(t) i-1 ) and V(t i+1 If the interpolated vibration value is: ; in: This represents the angular domain vibration amplitude (unit: m / s²) after resampling. The angle difference (in rad) between adjacent original sampling points.

[0038] S302: Perform a fast Fourier transform on the resampled angle domain signal to obtain the spectrum with the order as the abscissa. The order corresponding to the meshing frequency is equal to the number of teeth of the gear 8 under test. The orders corresponding to each harmonic of the meshing frequency are 2 times, 3 times and so on, respectively, the number of teeth of the gear 8 under test. Specifically: the resampled angular domain vibration amplitude V Performing a Fourier transform yields a spectrum with the order as the abscissa. In this embodiment, since the number of teeth on the gear under test is z=30, the order corresponding to the meshing frequency is 30; its second harmonic order is 2z=60, and so on. The amplitude at the corresponding order in the order spectrum is the vibration amplitude of the meshing frequency and its harmonics, denoted as A. 1X A 2X The units are all m / s².

[0039] S303: Directly calculate the root mean square value of vibration, impulse factor and vibration kurtosis based on the angle domain signal; extract the meshing frequency and vibration amplitude at the harmonics based on the order spectrum; based on the angle domain signal (take 3 complete gear rings, N=3=3×1024=3072 points). The formula for calculating the root mean square value of vibration is: ; in: Let be the j-th sampled value of the angle domain signal. This value reflects the average energy level of the vibration signal, and the larger the value, the more intense the meshing.

[0040] The formula for calculating the impulse factor is: ; in: Let be the number of pulse peaks with an absolute value greater than 3σ, and σ = , The total number of sampling points is 3072 in this embodiment. The pulse factor reflects the frequency of impact on the tooth surface; the larger the value, the more concentrated the impact.

[0041] The formula for calculating vibration kurtosis is: ; in: This is the arithmetic mean of the signal, which is usually close to 0 for vibration signals.

[0042] Based on the above formula, the characteristic data for each torque level were calculated, resulting in the characteristic data shown in Table 1 (partial key levels): Table 1. Feature Value Data

[0043] As can be seen from Table 1, with the increase of load torque, the root mean square value of vibration, impulse factor, meshing frequency amplitude and vibration kurtosis all show an upward trend. In particular, when the torque increases from 132 N·m to 144 N·m, the impulse factor increases sharply from 0.0055 to 0.0120, an increase of more than 100%, indicating that the impact on the tooth surface is significantly aggravated at this time.

[0044] Sudden torque identification and determination: As in step S4 above, specifically, the controller 4 first automatically matches the pre-calibrated standard library data based on the data of the gear 8 to be tested. It should be noted here that the definitions of allowable values ​​and standard values ​​involved in this application are as follows: Allowable values: These refer to the upper limits of vibration characteristic parameters that the gear 8 under test is allowed to reach under rated operating conditions, including the allowable root mean square (RMS) vibration value and the allowable impulse factor. The allowable RMS vibration value measures whether the average energy level of gear meshing vibration exceeds the allowable range. Exceeding this value indicates that the gear pair has an excessive vibration response under rated load, which may be caused by tooth surface damage, tooth profile deviation, or insufficient strength. The allowable impulse factor measures the frequency of tooth surface impacts. Exceeding this value indicates abnormal impacts on the tooth surface, which may be caused by tooth surface pitting, spalling, or plastic deformation. All the above allowable values ​​are pre-stored in a database (standard library) and calibrated according to the module, tooth width, and material grade of the gear 8 under test.

[0045] Standard value: refers to the benchmark reference value of the meshing frequency and the vibration amplitude of each harmonic of the gear under test 8 under rated operating conditions. This standard value is determined by statistically averaging the meshing frequency amplitudes obtained by the actual measurement of qualified gears of the same model and batch under rated torque TN. It serves as a benchmark reference line for judging whether the gear under test 8 has eccentricity. If the vibration amplitude of the meshing frequency and its harmonics of the gear under test 8 under rated torque TN reaches twice or more of this standard value, it indicates that the gear has a significant eccentricity fault.

[0046] Allowable root mean square value of vibration V LIM =1.0, Permissible pulse factor I LIM =0.005, Standard value A of meshing frequency amplitude ST =0.15. The above allowable and standard values ​​are not fixed, but are dynamically updated. During the initial calibration phase of the equipment, at least 10 sets of standard gears of the same model (accuracy level not lower than 5) are repeatedly tested under rated torque, and the average value of each characteristic parameter is taken as the initial allowable and standard values ​​and stored in the database. In subsequent use, after every 100 qualified gears of the same model are tested, the system automatically adds the newly tested qualified data to the standard library and corrects the allowable and standard values ​​according to a weighted recursive algorithm (the correction weight is 20% for new data and 80% for the original standard value) to eliminate the cumulative impact of sensor zero drift, ambient temperature changes, and mechanical wear on threshold accuracy.

[0047] Calculate the rate of change based on the data obtained in step S3.

[0048] Calculate the rate of change of the root mean square value of vibration for two adjacent torque levels: ; Pulse factor change rate: ; Set threshold: when >0.05 or When the value is greater than 0.0005, a mutation is considered to have occurred, and the determination is made according to the judgment rules.

[0049] Based on the data in Table 1, the partial rate of change of vibration characteristics of adjacent torque levels is calculated, as shown in Table 2: Table 2. Data on the rate of change of vibration characteristics of adjacent torque levels

[0050] As can be seen from Table 2, when the torque increases from 132 N·m to 144 N·m, the rate of change of the pulse factor is 0.000542 / N·m, which exceeds the set threshold of 0.0005 / N·m. Therefore, a sudden change is determined, the torque of the sudden change is recorded, and then a judgment is made.

[0051] In some preferred embodiments, the determination rule in step S4 is as follows: If the sudden change torque is ≥120%TN, and the root mean square value of vibration under rated torque is ≤ the allowable value, and the vibration kurtosis is ≤4, then the meshing strength is deemed to be qualified. If the sudden torque is between 100% and 120% TN, and the vibration amplitude of the meshing frequency and its harmonics under the rated torque is ≥ twice the standard value, then it is determined that there is eccentricity of the gear under test 8, and the meshing strength has reached the critical point. If the sudden torque is less than 100%TN, or the pulse factor under rated torque is greater than the allowable value, or the vibration kurtosis is greater than 5, then the meshing strength is deemed unqualified.

[0052] Specifically, according to the matching criteria, the allowable root mean square value of vibration V is... LIM =1.0, Permissible pulse factor I LIM =0.005, Standard value A of meshing frequency amplitude ST =0.15. Based on the data in Tables 1 and 2, the decision rules are applied to obtain Table 3: Table 3 Judgment Rules

[0053] According to the judgment results in Table 3, the gear 8 under test meets the conditions of "the sudden torque is between 100% and 120% TN" and "the amplitude of the meshing frequency under rated torque is ≥ twice the standard value". Therefore, it is finally determined that: there is eccentricity in the gear 8 under test and the meshing strength has reached the critical point.

[0054] In some preferred embodiments, the vibration characteristic standard range in step S4 adopts a dynamic update strategy. After each predetermined number of qualified gears of the same model are tested, the new test data is included in the standard library, and the threshold range is automatically corrected.

[0055] Example 2: This invention also provides an apparatus based on an adaptive fast gear meshing detection method, see reference. Figures 3-6The test assembly includes a base 1, on which a support frame 2, a drive frame 3, and a controller 4 are mounted. A swing frame 5 is also movably mounted on the support frame 2. The swing frame 5 can rotate along the support frame 2. The swing frame 5 includes a first rotating shaft 50 and a set of swing arms 51 mounted on the first rotating shaft 50. The first rotating shaft 50 is lockable, primarily during testing to prevent rotation. This embodiment does not show the locking mechanism. A spacing adjustment mechanism 6 is also mounted on the two swing arms 51. The spacing adjustment mechanism 6 mainly adjusts the spacing between the first push rod 71 and the second push rod 72 to accommodate gears of different widths. 8. Furthermore, the front ends of the two swing arms 51 are equipped with pre-tightening mechanisms 7. The spacing adjustment mechanism 6 also cooperates with one end of the pre-tightening mechanism 7. A gear 8 to be tested is also installed between the pre-tightening mechanisms 7. The pre-tightening mechanism 7 mainly ensures the formation of axial pre-tightening force. A standard gear 9 is installed on the drive frame 3. One side of the drive frame 3 is also connected to a servo motor 11 via a transmission component 10. An encoder 12 is also installed on the rotating shaft of the drive frame 3. The gear 8 to be tested is located above the standard gear 9 and meshes with it. A vertical support rod 13 is also vertically installed on the base 1. A vibration sensor 14 is also movably installed on the support rod 13. (See reference...) Figure 5 Furthermore, the bottom of the vibration sensor 14 is in contact with the plate 52 on the first rotating shaft 50. When the servo motor 11 drives the standard gear 9 to rotate, the gear 8 under test is also driven to rotate. During meshing, the contact force between the tooth surfaces (including normal pressure and tangential friction) is transmitted to the front end of the swing arm 51 through the shaft of the gear 8 under test, causing the swing arm 51 to swing around the first rotating shaft 50. This swinging tendency is supported by the plate 52 on the first rotating shaft 50 and is ultimately collected by the vibration sensor 14 as a vibration acceleration signal.

[0056] In some preferred embodiments, see Figure 4 The spacing adjustment mechanism 6 includes a connecting bushing 60, which is horizontally and vertically connected to two swing arms 51. An adjusting shaft 61 is installed inside the connecting bushing 60. A connecting plate 62 is fixedly installed at the other end of the adjusting shaft 61. A pre-tightening mechanism 7 is also installed at the other end of the connecting plate 62. When the adjusting shaft 61 is rotated, since the connecting bushing 60 is fixed to the two swing arms 51, the rotational motion of the adjusting shaft 61 is converted into axial movement, which drives the connecting plate 62 to move left and right. When the connecting plate 62 moves, the pre-tightening mechanism 7 connected to it moves as a whole, thereby changing the distance between the first push rod 71 and the second push rod 72.

[0057] In some preferred embodiments, see Figures 4-5The pre-tightening mechanism 7 includes an adjusting handle 70, which is movably mounted on the outer side of the connecting plate 62. A first push rod 71 and a second push rod 72 are rotatably mounted at the front ends of the two swing arms 51, respectively. The first push rod 71 and the second push rod 72 are used to mount the gear 8 to be tested. The first push rod 71 also cooperates with a load brake 15, which is mounted on the inner side of one of the swing arms 51. The distal end of the second push rod 72 passes through the connecting plate 62 and is threadedly engaged with the adjusting handle 70. The inner side of the connecting plate 62 is close to the swing arm 51, and a spring 73 is fixedly mounted therebetween. The spring 73 is also fitted onto the second push rod 72. The rotational movement of the adjusting handle 70 is converted into axial movement of the second push rod 72 via a thread. When the second push rod 72 moves inward, it compresses the spring 73, which generates an elastic restoring force. This force is transmitted to one side of the gear 8 under test through the head of the second push rod 72. At the same time, the other side of the gear 8 under test is held against by the first push rod 71, thereby forming an axial preload. This structure ensures that the tooth surfaces of the gear 8 under test and the standard gear 9 are always in contact, avoiding impact interference to the detection signal caused by gaps. Secondly, it provides an initial load: so that the gear pair is already in a slightly compressed state when unloaded, which facilitates a smooth transition of the signal during subsequent graded loading.

[0058] In some preferred embodiments, see Figure 6 The vibration sensor 14 is a piezoelectric accelerometer, and a coupling agent is coated between its bottom and the plate 52 on the first rotating shaft 50.

[0059] In some preferred embodiments, see Figure 6 The load brake 15 is a magnetic powder brake, with its stator fixed inside the swing arm 51 and its rotor coaxially connected to the first push rod 71. The braking torque is adjusted by the analog current output by the controller 4.

[0060] Specifically, the load brake 15 (in this embodiment, a magnetic powder brake) is installed inside the swing arm 51, and its rotor is coaxially connected to the first push rod 71. When the controller 4 outputs an analog current command to the load brake 15, the magnetic powder inside the magnetic powder brake forms a shear resistance under the action of the magnetic field. This resistance is transmitted through the rotor to the first push rod 71, and then to the shaft of the gear under test 8, forming a braking torque that hinders the rotation of the gear under test 8. At the same time, the servo motor 11 drives the standard gear 9 to rotate in a constant speed mode. Since the gear under test 8 meshes with the standard gear 9, the braking torque generated by the load brake 15 is transmitted in reverse to the servo motor 11 through the meshing point. The driver of the servo motor 11 automatically increases the output torque to overcome this resistance torque, thereby maintaining the set speed unchanged. In this working mode, the actual load torque applied to the meshing point of the gear pair is equal to the braking torque of the load brake 15 (ignoring bearing friction losses). Therefore, by precisely adjusting the input current of the load brake 15 by the controller 4, precise control of the meshing load can be achieved.

[0061] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. An adaptive rapid gear meshing detection method, characterized in that, Includes the following steps: S1: Install the gear to be tested on the testing device, mesh the gear to be tested with the standard gear and apply a preload, start the standard gear to rotate, and obtain the reference signal V0; S2: Outputs progressively increasing braking torque commands to the load brake, setting the rated torque TN; simultaneously drives the standard gear to rotate at a constant speed, and after each torque level stabilizes, collects the real-time rotation angle θ of the standard gear, and synchronously collects the vibration signal VI. S3: Perform order tracking on the vibration signal VI and real-time rotation angle θ at each torque level, extract vibration feature parameters and construct a vibration feature vector. The vibration feature parameters include at least the root mean square value of vibration, the amplitude of meshing frequency, the impulse factor and the vibration kurtosis. S4: Based on the parameters of the gear under test, automatically match the corresponding vibration characteristic standard range in the database, calculate the rate of change of the root mean square value of vibration or the impulse factor under two adjacent torque levels, and when the rate of change exceeds the set threshold, record the current torque value as the sudden torque and judge the meshing strength according to the judgment rules. S5: Outputs a comprehensive rating and fault type indication, and generates a traceable inspection report.

2. The adaptive rapid gear meshing detection method according to claim 1, characterized in that, In step S1, the preload is achieved by controlling the spring compression by adjusting the rotation angle of the adjustment handle. The preload range is 5-40N, and it is automatically matched according to the module of the gear to be tested, so that the tooth surface of the gear to be tested and the standard gear maintains a backlash-free contact and does not generate static friction. In step S2, the load brake is a magnetic powder brake or an eddy current brake, which is coaxially connected to the first push rod of the gear to be tested, and the loading accuracy is controlled by a torque sensor in a closed loop, with a deviation not exceeding ±1%.

3. The adaptive rapid gear meshing detection method according to claim 1, characterized in that, In step S3, the order tracking step includes: S300: Calculate the position of the gear under test at each sampling moment based on the real-time rotation angle θ output by the encoder; S301: Resample the vibration signal VI at equal angular intervals, using the fixed number of angle points for each tooth ring as the target, and convert the original non-uniform time series into a uniform angle series; S302: Perform a fast Fourier transform on the resampled angle domain signal to obtain the spectrum with the order as the abscissa. The order corresponding to the meshing frequency is equal to the number of teeth of the gear under test, and the order corresponding to each harmonic of the meshing frequency is an integer multiple of the number of teeth of the gear under test. S303: Directly calculates the root mean square value of vibration, impulse factor and vibration kurtosis based on the angle domain signal, and extracts the meshing frequency and vibration amplitude at the harmonic frequency based on the order spectrum.

4. The adaptive rapid gear meshing detection method according to claim 1, characterized in that, The determination rules described in step S4 are as follows: If the sudden change torque is ≥120%TN, and the root mean square value of vibration under the rated torque TN is ≤ the allowable value, and the vibration kurtosis is ≤4, then the meshing strength is deemed qualified. If the sudden torque is between 100% and 120% of TN, and the vibration amplitude of the meshing frequency and its harmonics under the rated torque TN is ≥ twice the standard value, it is determined that there is eccentricity of the gear under test and the meshing strength has reached the critical point. If the sudden torque is less than 100% TN, or the pulse factor under the rated torque TN is greater than the allowable value, or the vibration kurtosis is greater than 5, then the meshing strength is deemed unqualified.

5. The adaptive rapid gear meshing detection method according to claim 1, characterized in that, The vibration characteristic standard range in step S4 adopts a dynamic update strategy. After testing a predetermined number of qualified gears of the same model, the new test data is included in the standard library, and the threshold range is automatically corrected.

6. An adaptive rapid gear meshing detection device, used to implement the adaptive rapid gear meshing detection method according to any one of claims 1-5, characterized in that, The device includes a base, on which a support frame, a drive frame, and a controller are mounted. A swing frame is movably mounted on the support frame. The swing frame includes a first rotating shaft and a set of swing arms mounted on the first rotating shaft. Two swing arms are equipped with a spacing adjustment mechanism for adjusting the distance between a first and second push rod. A pre-tightening mechanism is also fitted at the front end of each swing arm. The spacing adjustment mechanism cooperates with one end of the pre-tightening mechanism. A gear to be tested is fitted between the pre-tightening mechanisms. A standard gear is mounted on the drive frame. One side of the drive frame is connected to a servo motor via a transmission component. An encoder is mounted on the rotating shaft of the drive frame. The gear to be tested is located above the standard gear and meshes with it. A vertical support rod is also mounted on the base. A vibration sensor is movably mounted on the support rod, and the bottom of the vibration sensor contacts a flat plate on the first rotating shaft.

7. The adaptive rapid gear meshing detection device according to claim 6, characterized in that, The spacing adjustment mechanism includes a connecting bushing, which is horizontally and vertically connected to two swing arms. An adjusting shaft is installed inside the connecting bushing, and a connecting plate is fixedly installed at the other end of the adjusting shaft. A pre-tightening mechanism is also installed at the other end of the connecting plate.

8. The adaptive rapid gear meshing detection device according to claim 6, characterized in that, The pre-tightening mechanism includes an adjusting handle, which is movably mounted on the outside of the connecting plate. The front ends of the two swing arms are respectively provided with a first push rod and a second push rod. The first push rod and the second push rod are used to install the gear to be tested. The first push rod also cooperates with a load brake, which is installed on the inside of one of the swing arms. The distal end of the second push rod also passes through the connecting plate and cooperates with the adjusting handle. The inside of the connecting plate is close to the swing arm, and a spring is fixedly installed between them. The spring is also fitted on the second push rod.

9. The adaptive rapid gear meshing detection device according to claim 6, characterized in that, The vibration sensor is a piezoelectric accelerometer, and a coupling agent is coated between its bottom and the plate on the first rotating shaft.

10. The adaptive rapid gear meshing detection device according to claim 6, characterized in that, The load brake is a magnetic powder brake, with its stator fixed to the inside of the swing arm and its rotor coaxially connected to the first push rod. The braking torque is adjusted by the analog current output by the controller.

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