Design And Optimization Of High Precision CNC Vertical Turning And Milling Machining Center

High precision CNC vertical turning and milling machining center is one kinds of advanced CNC machine tool equipment.It is mainly used for the rough and finish machining of the disk,ring,inner/outer cylindrical surface,inner/outer conical surface,end face and other large-scale parts.Stator and rotor in large-scale wind power equipment.Rotating base and support in large construction machinery.Leaf ring and leaf disc of aeroengine.Processing of large-size parts such as tunneling plate in large shield machine.High precision vertical CNC turning center is the main manufacturing equipment to ensure the machining accuracy and performance of this kind of parts.This thesis combined the development project of new product of a high precision CNC vertical turning and milling machining center in the company,and does a research the key technology of high precision CNC vertical turning and milling center in order to realize the high precision,high speed and high stability of the while machine.Meanwhile,we also optimize the basic components of this machine to improve the accuracy.So the main research contents including the following aspects.(1)First of all,according to the functional requirements of high precision CNC vertical turning and milling machining center,we determine the overall layout and design of the machining center.(2)This thesis mainly gives an introduction of the construction design of triaxial feed driving,main spindle,rotated worktable and tool magazine and the various components of the system,and analyzes vertical balance motion system of the main shaft of the vertical turning center.(3)Establishing finite element model of high precision CNC vertical turning and milling machining center bed and column and then analyzing the actual machining of the machining center based on the force analysis and the calculation of cutting force.Finally,carrying on the first period finite element analysis,including mesh,constraints,loads.According the finite element theory,the paper analyses the static analysis and modal analysis of the bed and column.On the basis of above analysis,finding out the weakness of the body structure,and determining where is in need of improvement pointing out direction for subsequent optimization.(4)We analyze the stiffened plate on the bed inside.It firstly puts forward three ribs layout plans and analyzes them,and takes the bed structural's natural frequency optimization as an objective,in order to select a reasonable layout of the form ribs.Then extracting the unit structure of a typical bed based on structural optimization method arriving at a reasonable structural optimization parameters.Base on the results of unit structure,we put forward two optimization designs of the bed through the comparative analysis to make the final optimization.The topology optimization of the column was made by variable density method,obtaining the optimal material distribution of the columns structure and carrying out the analysis with static and dynamic analysis of the optimized column structure.The results show that the quality of the column is reduced and the fundamental frequency is improved which has expected optimization result.