Research On Error Analysis And Optimization Design Of CNC Machine With Linear Motor

Requirements of CNC machine tools’ function increase more and more with the development of modern manufacturing industry. Super high speed cutting and ultra-precision are the development direction of machine tools. Compared with the way of traditional transmission, Linear motor drive system has obvious advantages, but has some urgent problems to be solved. The heat and normal force will cause deformation of machine tool structure, when permanent magnet linear synchronous motor applied to CNC machine tools. The excellent features of the linear motor feed system are seriously restricted. Therefore, Finite element method and experiment method are adopted in this thesis to study the heat and normal magnetic force issues. Optimizing the structure of machine tools improve the machining precision.(1) The normal force of linear motor is explored by the electromagnetic theory. Considering stiffness of joint surface of linear motor feed system, use method of structure analysis to do the finite element structure analysis of linear motor feed system. Laser displacement sensor is used to test the deformation and get the law of deformation. Simulation results and experimental results are compared.(2) Further study of heat transfer theory, linear motor generating heat and the surface heat transfer coefficient of feed system are discussed. The thermal-structural coupled finite element method is used to simulate the thermal properties of the linear motor feed system. According to the simulation results, the law of thermal conductivity and thermal deformation is analyzed. Temperature inspection instrument and laser displacement sensor are used to measure the temperature rise and get the law of temperature field and deformation. Simulation results and experimental results are compared.(3) Thermal-structure of the high speed vertical machining center VH1100is done by using the methods of normal force and heat simulation. Under the effect of thermal load and normal force, the weakness of structure is explored. Using optimization design module of ANSYS, the structure optimization of high speed vertical machining center VH1100is completed.