Finite Element Analysis And Optimization On Structure Of High-speed CNC Gear Milling Machine

The finite element method (FEM) and modal analysis theory are becoming more and more popular in the design of modern machine tools. Because the high-speed gear milling machine discussed here has a high cutting speed and big cutting output, a reasonable machine structure which has better dynamic and static performance should be guaranteed. Furthermore, this machine is a single-piece production, it should have the capability to meet the hereinbefore requirement in the initial design stage. Based on the FEM and modal analysis theory, the paper builds the finite element model of the high-speed gear milling machine. By FEM calculation, the static and dynamic characteristics of the parts and whole machine tool are highly improved. The application of these new methods not only improve the working capability and machining precision of the new machine tool, but also reduce the developing costs of new production and development circle. The main works are as follow:(1) After importing the Pro/E-based entity models to ANSYS, the finite element models are built for static and modal analyses. The calculation results indicate that the more element number applied, the more accurate natural frequency value can be obtained in the modal analysis of upright column.(2) By altering the layout and thickness of the inner ribs, the dynamic characteristics of the upright column are calculated. The calculation results indicate that the two parameters play a significant role on the dynamic performance of the upright column.(3) The finite element model of whole machine tool is built up. By FEM calculation, the results such as the stress and deformation distribution are displayed by ANSYS. The result is 4.5% smaller than that of the single calculation of upright column. By comparing, the calculation of whole machine tool has simple and accurate loads relatively and a more precise calculation result.(4) Some classical dynamic models as well as the characteristic parameters of joining surface are completed. After carrying out the finite element analysis on the dynamic model of the whole machine tool, the calculation results show that the weaknesses of structure are the joining surface. The dynamic performance can be improved obviously by enhancing the rigidity of the joining surface.(5) The structure of drive shaft is optimized by applying FEA and optimization theory. The optimum design of simple parts can be attained in this way.