Thermal Error Modeling And Experimental Research For Spindle Of CNC Machine Tool

In today's world,the technical level of CNC machine tools directly determines the level of development of national manufacturing industry,is the core of national advanced manufacturing technology,and embody the national comprehensive strength and the level of equipment manufacturing.It is of great significance to research the thermal error of the machine tool spindle to improve the accuracy of machine.In this paper,the three-axis CNC machine tool produced by Nanjing Dexi CNC New Technology Company are taken as the research object,and the thermal deformation mechanism of CNC machine tool spindle is studied.Firstly,the temperature field of the spindle system is analyzed and calculated,and the key heat source and heat quantity in the spindle temperature field are obtained.The heat transfer relationship of each part in the spindle system is calculated under its respective boundary conditions.The finite element simulation method is used to simulate the temperature field and deformation field of the spindle at different rotational speeds.The relationship between the temperature field and the deformation field is obtained.At the same time,the temperature of the special temperature mark on the box are obtained too.The data acquisition system is used to collect the data of the thermal error of the spindle and the special temperature of the spindle box.The relationship between the temperature value of the different temperature point,the thermal error of the spindle and the temperature data at different rotational speeds are obtained.Thermal error data are compared with the finite element simulation results to verify the accuracy of the results of finite element simulation.The fuzzy clustering and gray system theory are used to evaluate and select the temperature tag points,and a set of optimal temperature test points are obtained.The thermal error model of the machine tool is modeled by the natural selection of the particle swarm algorithm(SelPSO)and the thermal error model is compared with the regression model and the thermal error model of the machine tool spindle established by the standard particle swarm algorithm.The selected particle swarm algorithm(SelPSO)establishes a spindle system thermal error model with higher accuracy.