Monitoring And Experimental Research On Thermal Performance Of Spindle System Of CNC Lathe Under Complex Conditions

Computer numerical control(CNC)machine tool is a modern sophisticated manufacturing equipment,and its technical level and manufacturing capacity are important symbols of national comprehensive strength.Due to the flexibility of CNC machining process and the complexity of work conditions,the monitoring of thermal performance of CNC machine tools will become more complicated.Regarding CNC lathe as the research object,in this paper off-line and on-line are combined to monitor the thermal performance of CNC lathe under complex working conditions,and the design of thermal performance monitoring system has been completed.The contributions of this dissertation may be summarized as follows:(1)Base on the analysis of thermal performance monitor requirements.the digital prototype of the off-line simulation test and on-line experimental are combined to monitor the thermal performance of CNC lathe.First the off-line monitoring is set up to the spindle system.According to the principle of heat transfer machine principle,ANSYS Workbench is used for finite element simulation of spindle system of CNC machine tools,The off-line monitoring results of spindle system temperature and thermal deformation are obtained,which provides guidance for layout of temperature measurement points and arrangement of thermal deformation measurement points in on-line monitoring experiments.(2)Base on the analysis of on-line monitoring requirements.thermal performance monitor experiment of CNC machine tools are designed under complex conditions.The temperature data and the thermal error data of spindle system are collected.In order to reduce the correlation between temperature measurement points,the correlation coefficient method is applied to further optimize the temperature measurement points of spindle system.The 10 temperature measurement points obtained by finite element simulation results are reduced to 4 sensitive points.(3)According to the existing problems of low prediction accuracy and poor robustness of error model,the modeling method of interactive GM-BP neural network is proposed for the first time,and compared with the GM method and BP neural networkmethod,the prediction precision and robustness of the interaction effect of GM-BP neural network thermal error model is better than the other two models.(4)The thermal performance monitoring system of the spindel system of CNC machine tools is set up using LabVIEW and MATLAB,The software system has the following functions user management test management of temperature rise and thermal deformation thermal performance data processing and data query,it could process off-line data and monitor on-line data of the spindle system.In this paper,off-line and on-line are combined to monitor the thermal performance of CNC lathe under complex working conditions,which provides a basis for steady state control and health maintenance of thermal performance of CNC manufacturing equipment,and it also plays an extremely important role in predicting the thermal performance under complex conditions.