Research On Structure Improvement Of WT700 CNC Gear Milling Machine

Based on the theory and method of structure optimization design at home and abroad,this paper takes wt700 CNC gear milling machine as the research object.Starting from the analysis of the dynamic and static characteristics of the complete machine and key components of the gear milling machine,the optimization design of the gear milling machine structure is carried out.In order to reduce the deformation of the gear milling machine components and improve the stiffness of the gear milling machine as the goal,the problem of insufficient stiffness of the machine tool components during the processing of the gear milling machine will be improved.Finally,the structure improvement of gear milling machine is completed.The main work content of the research includes:(1)The finite element modeling of wt700 CNC gear milling machine is carried out.Through the analysis of the static performance of the whole machine combined with the actual working conditions,the weak stiffness structure of the whole machine is obtained.By analyzing the dynamic performance of the whole machine,the dynamic performance data of the gear milling machine is obtained.(2)For the topology optimization of the ram components of the gear milling machine,a multi-objective topology optimization mathematical model is established by introducing a compromise programming method of satisfaction.The topology optimization model of the ram is constructed according to the topological results of frequency and flexibility,and the element structure of the ram is extracted based on the topology model of the ram.By improving and comparing different types of element structure,taking the first-order natural frequency per unit mass as the selection criteria,choosing a four-hole element structure with better dynamic performance to replace the element structure of the ram,and realizing the structural improvement of the ram.(3)The topological optimization of the side wall of the bed is carried out without affecting the use,so as to form a new form of ribs,and the side wall model of the bed is reconstructed without changing the outer shape of the side wall of the bed.The parameter optimization of the internal rib size of the side wall of the bed is carried out by the response surface method.Taking the minimum mass of the side wall of the bed,the largest first-order frequency,and the smallest total deformation as the goal,the internal rib size of the side wall of the bed is optimized by multi-objectives,and the structural improvement of the internal ribs of the side wall of the bed is completed.It can improve the rigidity and reduce the mass without affecting the conditions of use.(4)The optimized ram and the side wall of the bed were reassembled into the WT700 CNC gear milling machine model,and the whole machine was subjected to static analysis and modal analysis under the same conditions.The data shows that after the improvement,the total deformation of the WT700 CNC gear milling machine is reduced by 18.4%,and the first-order natural frequency is increased by 13.5%.According to the analysis theory of dynamics and statics,the rigidity of the whole machine is improved,which verifies the importance of optimizing the parts of CNC machine tools to the improvement of the performance of the whole machine,and realizes the goal of structural improvement of the gear milling machine.