Research On Thermal Error Mechanism And Compensation Strategy Of Synthesis Error For Five-axis CNC Machine

With the wide application of the complex geometry parts, the precision demand is higher and higher. The precision of multi-axis CNC machine tools that produce parts directly affect the precision of process parts. Error is one of the key factors influence the accuracy of machine tools and account for 70% of the total error of machine tools result from geometric error and thermal error. In this paper, taken the independent research five-axis machine as the researched subject, research the mechanism of thermal error, the analysis of thermal characteristic of machine tools spindle is concerned, research the errors detection and separation and modeling and error compensation strategy of geometric and thermal about feed shaft. The main research work are as follows several aspects:1 The analysis of the sliding joints and revolute pair of machine tools, analysis of the error of the spindle. Research the mechanism of spindle thermal deformation and thermal characteristic theory.2 Establish the finite element analysis model of spindle and calculate the thermal boundary conditions. Research the temperature and thermal deformation of spindle according to the thermal boundary conditions and analysis the reasons. Analysis the thermal deformation under different rotational speed. Thermal error is the factor that cannot ignore and provide the measures to improve the spindle thermal deformation.3 Research the measure method of positioning error and temperature of machine tools guide under the influence of geometric error and thermal error. According to positioning error curve change rule separate the geometric and thermal error and establish the geometric and thermal modeling respectively, finally obtained the comprehensive error modeling.4 Research the comprehensive error compensation strategy, the error compensation strategy based on measurement technology is put forward.