Identification and Optimization of Weak Links in Stiffness Characteristics of Direct-driving Machine Tools
In order to improve the optimization efficiency of the direct-driving machine tool,improve the static and dynamic performance and achieve lightweighting,an optimization idea of analyzing the stiffness characteristics of the machine tool to guide the improvement of weak parts is put forward.Based on the finite element method and the series stiffness field theory,the static analysis,modal analysis and harmonious response analysis of the three-axis direct-driving machining center are carried out,and the crossbeam column is identified as the weakest link of the static stiffness and the first and second mode shapes of the entire machine.A new structure of crossbeam and column is designed and obtained using the method of topology optimization,sensitivity analysis and size optimization.Compared with the crossbeam column structure and the performance of the entire machine before and after optimization,the results show that the static deformation of the new crossbeam column in the three directions of xyz is reduced by 27.8％,9.3％and 10.3％,respectively;the first two natural frequencies are increased by 23.6％and 11.0％,respectively;and the weight reduction of the crossbeam column structure is 9.0％.The overall stiffness of the direct-driving machine tool was significantly improved,and the maximum resonance peak in the three directions of xyz decreased by 31.1％,22.5％and 16.0％,respectively.Under the premise of reducing the mass of the crossbeam column,the static and dynamic performance of the direct-driving machine tool is significantly improved.
direct-driving machine toolmachine toolstiffness characteristicweak link identificationstructure optimization
NETL
NSTL
万方数据
