Research on thermal dynamics characteristics and modeling approach of ball screw

Empirical modeling of machine tools on thermal error has been widely researched, which can compensate for thermal error to some extent but not suitable for thermal dynamic error produced by dynamics heat sources. Ball screw is the main member of feed system of machine tool. On the basis of the theory of heat transfer, thermoelastic phenomenon of unidimensional heat transferring of the ball screw influenced by changeable heat sources is analyzed. A method to establish a dynamics characteristics model of thermal deformation of the ball screw based on least square system identification theory is put forward. Through simulation data, correctness and validity of modeling approach is proven. By this method, modeling of thermal error of X-axis of feed system of DM4600 vertical miller is established which has good identification effect.