An accuracy degradation analysis of ball screw mechanism considering time-varying motion and loading working conditions

Ball screw mechanism (BSM) plays a key role to transmit motion and power in a machine tool. The accuracy of the machine tool is greatly influenced by the accuracy of the BSM. Since accuracy degradation of BSM is primarily due to wear, the wear behavior of BSM is studied considering the time-varying motion and loading working conditions. A new wear prediction model of BSM is introduced in this research considering complex working conditions. Because BSM is subject to dynamic fluctuations of rotational speed and loading in the operation process, a loading model is established to describe the dynamic contact force between the ball and the raceway, and a motion model is developed to describe the dynamic sliding and rolling behaviors between the ball and the raceway. The degradation of BSM accuracy is analyzed considering time-varying motion and loading working conditions. Experiments have also been designed and conducted to demonstrate the effectiveness of the accuracy degradation analysis for BSM. Crown Copyright (C) 2018 Published by Elsevier Ltd. All rights reserved.