Vibration analysis of highl-speed ball-screw drive in machine tool feed system

摘要

This paper studies the dynamic response of a high-speed ball-screw drive in a machine tool feed system. The Timoshenko beam theory is employed to model the rotating screw, while the nut is modeled as a lumped moving mass subjected to an external force resolved into three mutually perpendicular components. The dynamic model of the ball-screw drive is formulated based on the assumed mode method. To study the deformation characteristics of the ball-screw drive with different constrains, the dynamic equations are solved by using the fourth order Runge-Kutta method. In this paper, the moving mass and force effect are taken into consideration synchronously, and the relative velocity relationship of screw and nut is studied as well. The results show that the pitch of the screw, which determines the relative speeds of the rotating beam with respect to the moving excitation, have strong influences on the lateral deformation. Major factors affecting the ball-screw drive deformation are identified to illustrate its vibration performance.