Numerical control gear milling machine spindle box machining process analysis method based on combination of virtual simulation and test
Through the combination of virtual simulation and experiment, the machining performance of the spindle box of the small and large-tooth wide milling machine was compared and analyzed, and the problems of reduced machining accuracy and increased failure rate were solved, influencing factors were found and processing accuracy and equipment reliability were improved.
Patent Information
- Application Number
- CN202411943862.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-27
- Publication Date
- 2025-05-30
AI Technical Summary
In the process of increasing the size and machining depth of wind power gearbox components, the spindle box machining accuracy of milling gear machine tools decreases, and the failure rate of large-tooth wide spindle box increases, making it difficult to effectively analyze the influencing factors.
Using a combination of virtual simulation and experiments, the strain, temperature, displacement and vibration acceleration data of the spindle box of small and large-tooth wide milling machine under different processing conditions is obtained through finite element analysis and multi-body dynamic model, and compared and analyze it to find key factors affecting machining accuracy and faults.
A comparison analysis of the machining performance of small and large-tooth wide spindle boxes was realized, and the main factors affecting machining accuracy and faults were found, which improved machining accuracy and equipment reliability.
Smart Images
Figure CN120068494A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of building a test system for a numerically controlled gear milling machine and virtual simulation analysis, and particularly relates to a method for analyzing the machining process of the spindle box of a numerically controlled gear milling machine based on the combination of virtual simulation and experiment. Background Art
[0002] The numerically controlled gear milling machine is an important machine tool in gear processing and is widely used in the precision gear manufacturing of industries such as automobiles, aviation, and heavy machinery. The machining accuracy of gears directly affects the key performance of the entire mechanical system, such as transmission efficiency, noise, and service life. Therefore, it is of great significance to improve the gear machining accuracy.
[0003] With the development of offshore wind power, the power of mainstream wind turbines is continuously increasing. Due to the significantly increased load-bearing capacity and harsh working environment of offshore wind power, in order to meet the requirements of high reliability, the sizes of the components of the wind power gearbox have increased. The gear width has developed from 200 mm to the current 700 mm, and some even reach 950 mm. The diameter of the gear ring has also expanded from 1000 mm to 14000 mm. To improve the load-bearing capacity and achieve large tooth width machining, the spindle box of the original small gear milling machine has been improved, and the spindle box of the large tooth width gear milling machine has been redesigned. At the same time, to improve the machining efficiency, the cutting depth of the gear milling machine has reached 35 mm, resulting in a problem of decreased machining accuracy. Summary of the Invention
[0004] The present invention provides a method for analyzing the machining process of the spindle box of a numerically controlled gear milling machine based on the combination of virtual simulation and experiment, which can comparatively analyze the machining performance of the ordinary spindle box and the large tooth width spindle box, and find the factors affecting gear machining accuracy and spindle box failures.
[0005] To achieve the above object, the technical solution of the present invention is as follows:
[0006] A method for analyzing the machining process of the spindle box of a numerically controlled gear milling machine based on the combination of virtual simulation and experiment, characterized in that: comparative analysis is carried out by means of the combination of virtual simulation and experiment, including the following steps:
[0007] S1. Conduct machining tests under the same machining conditions on small and large tooth width gear milling machines, and obtain the strain, temperature, displacement, and vibration acceleration data during the machining process;
[0008] S2. Establish finite element analysis models of the spindle boxes of small and large tooth width numerically controlled gear milling machines and a multi-body dynamics model of the spindle system;
[0009] S3. Calculate the cutting force and bearing reaction force during the machining process of the spindle box, apply them as boundary conditions to the finite element model of the box body for analysis and calculation, and set relevant connection contacts;
[0010] S4. Compare and analyze the machining performance of small and large tooth-width spindle boxes under the same machining conditions, calculate their displacements at different cutting depths and feed rates, and study their influence on machining accuracy.
[0011] S5. Analyze the spindle vibration signals of the spindle under different cutting depths, rotational speeds, and feed speeds through multi-body dynamics of the spindle, and then analyze the factors that have a greater impact on spindle vibration and faults through multi-factor analysis.
[0012] S6. Construct an orthogonal response surface test system that includes three factors: cutting depth, rotational speed, and feed speed, and each factor is set at three levels, and deeply analyze the significance of the influence of these three factors on the evaluation index.
[0013] S7. Verify the correctness of the simulation analysis through test data, and further illustrate that the simulation analysis under other conditions based on this has a certain degree of accuracy.
[0014] Furthermore, the spindle box of the small CNC gear milling machine in S1 is used to machine small wind power gears with a workpiece diameter of less than 2000 mm and a tooth width of less than 300 mm, and the large tooth-width spindle box is used to machine large wind power gears with a workpiece diameter of 3000 - 4000 mm and a tooth width of more than 700 mm. The test system involved includes: a sensor module, a data acquisition module, a data storage module, and a data processing module.
[0015] The sensor module includes a vibration acceleration sensor, a temperature sensor, and a laser displacement sensor. The vibration acceleration sensor includes a unidirectional acceleration sensor and a triaxial acceleration sensor, which are used to collect the vibration signals of each axis of the spindle box during the gear milling process and the vibration acceleration of the workpiece and the turntable; the temperature sensor is used to collect the temperature data of the spindle box during the gear milling process of the CNC gear milling machine, and the laser displacement sensor is used to collect the displacement signals of the X, Y, and Z axes of the spindle box.
[0016] The data acquisition module consists of a NI data acquisition card, a NI CompactDAQ chassis, and data acquisition software written based on LabVIEW software; the data acquisition card is used to convert and process the signals collected by the sensors; the data acquisition card is connected to the CompactDAQ chassis through a card slot; the CompactDAQ chassis is connected to a PC through a network cable, and the converted signals are displayed in the written LabVIEW data acquisition software.
[0017] The data storage module: stores the signals converted by the data acquisition card in the tdms format for preservation.
[0018] The data processing module: It includes time-frequency domain analysis of the collected data. Among them, time domain analysis is to perform time series analysis on data such as temperature, vibration, and displacement, observe the trend of its change over time, calculate statistical quantities such as mean, variance, and standard deviation, and understand the basic characteristics of the data; frequency domain analysis uses Fourier transform to convert time domain data to frequency domain and analyze the periodic components in the data.
[0019] Further, the finite element models in S2 are to establish small spindle box and large tooth width spindle box models through 3D modeling software, import them into the static structure analysis module of finite element software, and simplify the models. The involved spindle multi-body dynamics models include components such as tool shanks, left spindles, right spindles, left bearings, left bearing seats, right bearings, right bearing seats, and gears. They are modeled through 3D software and then imported into the dynamics analysis software to set corresponding contacts.
[0020] Further, the cutting force during the machining process of the spindle box in S3 can be determined according to empirical formulas (1)-(3).
[0021]
[0022] In the formula: P kw —Cutting power (kw); W—Cutting width (mm); F—Table feed rate (mm / min); d—Cutting depth (mm); η—Mechanical efficiency (0.8).
[0023]
[0024] In the formula: v—Cutting speed (m / min); D—Cutter diameter (mm); N—Cutter speed (r / min).
[0025]
[0026] In the formula: F is the cutting force.
[0027] The cutting component force in the X-axis is F x : F x = 0.4F;
[0028] The cutting component force in the Y-axis is F y : F y = 0.55F;
[0029] The cutting component force in the Z-axis is F z :
[0030] In step S3, the bearing reaction forces of the spindle box are calculated by establishing a dynamic model of the spindle box transmission system, setting the input speed, power of the input shaft, and load of the output shaft, calculating the forces on each bearing, and loading them onto the bearing holes of each shaft in the finite element analysis model of the spindle box to simulate the forces exerted on the box body by each shaft during the machining process of the spindle box.
[0031] Furthermore, in step S4, the machining performances of the small spindle box and the large tooth width spindle box are comparatively analyzed. The strains of the spindle box under corresponding machining conditions are simulated through virtual simulation, the strains under actual machining conditions are collected by the monitoring system, and the model is compared and corrected so that the error between the strain obtained by simulation and the strain collected by the test is within 5%. Then, the cutting forces and bearing reaction forces under different cutting depths and feed rates are calculated through empirical formulas and applied to the finite element model to obtain the deformation and stress of the spindle box under different cutting depths and feed rates, and further analyze the performance differences between the small spindle box and the large tooth width spindle box under the same machining parameters.
[0032] Furthermore, in step S5, the spindle vibration signals of the spindle under different cutting depths, speeds, and feed rates are analyzed through spindle multibody dynamics, and then the factors that have a greater impact on spindle vibration and faults are analyzed through multi-factor analysis. It mainly involves single-factor analysis. By changing the cutting forces under different cutting depths, speeds, and feed rates, the vibration accelerations of the spindle, the inner ring of the bearing, and the bearing seat are analyzed; multi-factor analysis mainly uses orthogonal response surface analysis to set the peak value and root mean square value of the vibration amplitude to judge the kurtosis and margin of faults. Description of the Drawings
[0033] Figure 1 is the schematic diagram of the test system.
[0034] Figure 2 is the schematic diagram of the test system software.
[0035] Figure 3 is the model diagram of the 2-meter ordinary spindle box.
[0036] Figure 4 is the model diagram of the 4-meter large tooth width spindle box.
[0037] Figure 5 is the schematic diagram of the force analysis model of the transmission system.
[0038] Figure 6 is the model diagram of the spindle system multibody dynamics.
[0039] Figure 7 is the schematic diagram of the comparative analysis results of the small spindle box and the large tooth width spindle box.
[0040] Figure 8 is the schematic diagram of the displacement of the large tooth width spindle box under different cutting depths.
[0041] Figure 9 It is a schematic diagram of the influence of three factors on the vibration peak value.
[0042] Figure 10 It is a schematic diagram of the influence of three factors on the root mean square value.
[0043] Figure 11 It is a schematic diagram of the influence of three factors on kurtosis.
[0044] Figure 12 It is a schematic diagram of the influence of three factors on margin. Specific implementation manners
[0046] The technical solution of this patent will be further described in detail below in combination with specific implementation manners. The following detailed description of the embodiments of the present disclosure provided in the drawings is not intended to limit the scope of the claimed present disclosure, but merely represents selected embodiments of the present disclosure. All other embodiments obtained by those skilled in the art based on the embodiments of the present disclosure without creative efforts fall within the scope of protection of the present disclosure.
[0047] The present invention mainly includes the following steps:
[0048] S1. Conduct machining tests under the same machining conditions on small and large tooth width milling machines, and obtain strain, temperature, displacement, and vibration acceleration data during the machining process.
[0049] S2. Establish finite element analysis models of the spindle boxes of small and large tooth width CNC milling machines and multi-body dynamics models of the spindle systems.
[0050] S3. Calculate the cutting force and bearing reaction force during the machining process of the spindle box, apply them as boundary conditions to the finite element model of the box for analysis and calculation, and set relevant connection contacts.
[0051] S4. Compare and analyze the machining performance of small and large tooth width spindle boxes under the same machining conditions, calculate their displacements at different cutting depths and feed rates, and study their influence on machining accuracy.
[0052] S5. Analyze the spindle vibration signals at different cutting depths, speeds, and feed rates through spindle multi-body dynamics, and further analyze the factors that have a greater impact on spindle vibration and faults through multi-factor analysis.
[0053] S6. Construct an orthogonal response surface test system including three factors of cutting depth, speed, and feed rate, and each factor is set to three levels, and deeply analyze the significance of the influence of these three factors on the evaluation index.
[0054] S7. Verify the correctness of the simulation analysis through test data, and further illustrate that the simulation analysis under other conditions based on this has a certain degree of accuracy.
[0055] Figure 1 is the schematic diagram of the test system, including the vibration module, temperature module, strain module and displacement module, connecting the hardware system. Figure 2 is the data acquisition software written based on LabVIEW for collecting test parameters. The following table shows the sampling rates and ranges of the corresponding parameters.
[0056]
[0057] Figure 2 and Figure 3 are the model diagrams of the ordinary headstock and the headstock with large tooth width. Figure 4 is the model diagram of the force analysis of the transmission system. By setting the rotational speed and input power on the input shaft and applying a load on the output shaft, the model is made to operate, simulating the transmission system of the actual headstock, calculating the forces on the bearings, and using them as boundary conditions to be applied to the bearing holes of each shaft of the headstock. Figure 6 are the displacement amounts of the small headstock and the headstock with large tooth width under the same processing conditions. It can be clearly seen that the headstock with large tooth width has less deformation and higher machining accuracy. Figure 7 is the displacement of the headstock with large tooth width at different cutting depths. As the cutting depth increases, the displacement of the headstock also increases. Therefore, the cutting depth should be reasonably selected during machining.
[0058] Figure 5 is the multi-body dynamics analysis model of the spindle system. The following table shows 17 groups of experimental groups required for establishing the orthogonal response surface analysis.
[0059]
[0060]
[0061] Analyze the data in the table, and the multiple quadratic regression equations of the cutting depth A, rotational speed B, and feed rate C on the peak value, root mean square value, kurtosis, and margin of the spindle vibration signal are as follows:
[0062] Peak value Y1 = 37.25 - 7.23*A + 3.45*B - 6.06*C - 1.05*A*B + 0.48*A*C - 0.1764*B*C - 1.47*A 2 - 0.234*B 2 - 0.4032*C 2 ;
[0063] Root mean square value Y2 = 5.38 - 1.09*A + 0.637*B - 0.7469*C - 0.1518*A*
[0064] B - 0.0135 * A * C + 0.2468 * B * C + 0.8737 * A 2 + 0.3265 * B 2 + 0.7803 * C 2 ;
[0065] Kurtosis Y3 = 3.72 - 0.1068 * A + 0.0427 * B - 0.1273 * C + 0.0303 * A * B + 0.0888 * A * C - 0.0449 * B * C - 0.3382 * A 2 - 0.1660 * B 2 - 0.2838 * C 2 ;
[0066] Margin Y4 = 5.74 - 0.2551 * A + 0.0145 * B - 0.2413 * C + 0.009 * A * B + 0.0944 * A * C - 0.0615 * B * C - 0.5687 * A 2 - 0.3410 * B 2 - 0.4312 * C 2 ;
[0067] From the coefficients before each parameter, it can be seen the influence degree of the parameter on the corresponding evaluation value. Among them, the peak value and the root mean square value are used to evaluate the vibration magnitude, and the kurtosis and the margin are used to evaluate the fault condition of the headstock. Figures 8 - 11 It is the 3D response surface of the influence of the pairwise combinations of the three factors on the four evaluation indicators.
[0068] The above are only some examples of the present invention, and thus do not limit the protection scope of the present invention. Any equivalent device or equivalent process made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be similarly included in the patent protection scope of the present invention.
Claims
1. A method for analyzing the machining process of a CNC gear milling machine spindle box based on a combination of virtual simulation and experiment, characterized in that: The comparative analysis is carried out by combining virtual simulation and experiment, which includes the following steps: S1. Carry out machining tests under the same machining conditions on small and large tooth width milling machines to obtain the strain, temperature, displacement and vibration acceleration data during the machining process; S2. Establish the finite element analysis model of the spindle box of small CNC gear milling machine and large tooth width CNC gear milling machine and the multi-body dynamics model of the spindle system; S3, calculating the cutting force and the bearing support reaction force during the spindle box machining process, applying them to the box body finite element model as boundary conditions for analysis and calculation, and setting relevant connection contacts; S4. Compare and analyze the machining performance of small and large tooth width spindle boxes under the same machining conditions, calculate their displacements at different cutting depths and feed rates, and study their effects on machining accuracy; S5. Analyze the spindle vibration signal at different cutting depths, rotation speeds, and feed speeds through spindle multi-body dynamics, and then analyze the factors that have a greater impact on spindle vibration and failure through multi-factor analysis; S6. Construct an orthogonal response surface test system including three factors: cutting depth, rotation speed and feed speed, and set each factor to three levels, and deeply analyze the significance of the influence of these three factors on the evaluation index; S7. The correctness of the simulation analysis is verified through test data, which further illustrates that the simulation analysis under other conditions based on this has a certain degree of accuracy.
2. The method for analyzing the machining process of a CNC gear milling machine spindle box based on a combination of virtual simulation and experiment according to claim 1 is characterized in that: The S1 small and medium-sized CNC milling machine spindle box is used to process small wind power gears with a workpiece diameter of less than 2000mm and a tooth width of less than 300mm. The large tooth width spindle box is used to process large wind power gears with a workpiece diameter of 3000-4000mm and a tooth width of more than 700mm. The test system involved includes: sensor module, data acquisition module, data storage module, and data processing module.
3. The method for analyzing the machining process of a CNC gear milling machine spindle box based on a combination of virtual simulation and experiment according to claim 1 is characterized in that: The sensor module includes a vibration acceleration sensor, a temperature sensor and a laser displacement sensor, wherein the vibration acceleration sensor includes a unidirectional acceleration sensor and a three-directional acceleration sensor, which is used to collect vibration signals of each axis of the spindle box and the vibration acceleration of the workpiece and the turntable during the cutting process of the CNC gear milling machine; the temperature sensor is used to collect temperature data of the spindle box during the cutting process of the CNC gear milling machine, and the laser displacement sensor is used to collect displacement signals of the X, Y and Z axes of the spindle box.
4. The method for analyzing the machining process of a CNC gear milling machine spindle box based on a combination of virtual simulation and experiment according to claim 1 is characterized in that: The data acquisition module includes an NI data acquisition card, an NI CompactDAQ chassis, and data acquisition software written based on LabVIEW software; the data acquisition card is used to convert and process the signals collected by the sensor; The data acquisition card is connected to the CompactDAQ chassis through a card slot; the CompactDAQ chassis is connected to a PC through a network cable, and the converted signal is displayed in the compiled labview data acquisition software.
5. The method for analyzing the machining process of a CNC gear milling machine spindle box based on a combination of virtual simulation and experiment according to claim 1 is characterized in that: The data storage module stores the signal converted by the data acquisition card in the TDM format. The data processing module includes time-frequency domain analysis of the collected data, wherein the time-domain analysis is time series analysis of temperature, vibration, displacement and other data, observing their trends over time, calculating statistics such as mean, variance, standard deviation, and understanding the basic characteristics of the data; Frequency domain analysis uses Fourier transform to convert time domain data into frequency domain and analyze the periodic components in the data.
6. The method for analyzing the machining process of a CNC gear milling machine spindle box based on a combination of virtual simulation and experiment according to claim 1 is characterized in that: The finite element model in S2 uses three-dimensional modeling software to establish a small spindle box and a large tooth width spindle box model, which is imported into the static structure analysis module of the finite element software and simplified. The spindle multi-body dynamics model involved, including the tool rod, left spindle, right spindle, left bearing, left bearing seat, right bearing, right bearing seat, gears and other components, is modeled through three-dimensional software and then imported into the dynamics analysis software to set the corresponding contact.
7. The method for analyzing the machining process of a CNC gear milling machine spindle box based on a combination of virtual simulation and experiment according to claim 1 is characterized in that: The cutting force of the spindle box machining process in S3 can be determined according to the empirical formulas (1)-(3); Where: P kw - cutting power (kw); W- cutting width (mm); F- table feed (mm / min); d- cutting depth (mm); η- mechanical efficiency (0.8); Where: v-cutting speed (m / min); D-cutter diameter (mm); N-cutter speed (r / min); Where: F is the cutting force; The X-axis cutting force is F x : F x =0.4F; The Y-axis cutting force is F y : F y =0.55F; The Z-axis cutting force is F z : The spindle box bearing support reaction force in S3 is achieved by establishing a spindle box transmission system dynamics model, setting the input speed and power of the input shaft and the load of the output shaft, calculating the force on each bearing, and loading it to the bearing holes of each axis in the spindle box finite element analysis model to simulate the force of each axis on the box body during the spindle box machining process.
8. The method for analyzing the machining process of a CNC gear milling machine spindle box based on a combination of virtual simulation and experiment according to claim 1 is characterized in that: In said S4, the machining performance of a small spindle box and a large tooth width spindle box are compared and analyzed, the strain of the spindle box under corresponding machining conditions is simulated by virtual simulation, the strain under actual machining conditions is collected by the monitoring system, and the comparison and correction model are performed so that the strain obtained by simulation and the strain collected by test are within 5%; Then, the cutting force and bearing support reaction force at different cutting depths and feed rates are calculated using empirical formulas, and applied to the finite element model to obtain the spindle box deformation and stress at different cutting depths and feed rates, and then the performance differences between small spindle boxes and large tooth width spindle boxes under the same machining parameters are analyzed.
9. The method for analyzing the machining process of a CNC gear milling machine spindle box based on a combination of virtual simulation and experiment according to claim 1, characterized in that: In the S5, the spindle vibration signal of the spindle at different cutting depths, rotation speeds and feed speeds is analyzed by spindle multi-body dynamics, and then the factors that have a greater impact on the spindle vibration and failure are analyzed by multi-factor analysis; it mainly involves single factor analysis, by changing the cutting force at different cutting depths, rotation speeds and feed speeds, and analyzing the vibration acceleration of the spindle, bearing inner ring, bearing inner ring and bearing seat under various factors; multi-factor analysis is mainly carried out through orthogonal response surface analysis to establish the peak value and root mean square value of the vibration amplitude to judge the kurtosis and margin of the fault.