An analysis method for the transmission efficiency of the preloaded ball screw based on wear volume calculation

The transmission efficiency is an aggregative indicator that directly reflects the overall performance of the ball screw. While most researches focus on calculating transmission efficiency under different working conditions, few of them investigate the influencing factors that lead to the transmission efficiency change. To this end, this paper proposed a new analysis method to acquire the changing transmission efficiency with running revolution based on wear volume calculation considering lubrication. The fractal theory is introduced to describe the surface roughness, through which the modified expression of the wear volume between the balls and raceway is proposed. By submitting the wear volume into the transmission efficiency analysis model, the change of the transmission efficiency is obtained. From the experimental results, two obvious stages are shown: the rising stage with the increase of the wear volume and a steady stage as the initial preload vanishes. For higher transmission efficiency for the preloaded ball screw of the same type, the ratio of 0.75, which compares the initial preload to the external load, has some certain reference for the practical application.