A thermal model of a ball screw feed drive system for a machine tool

Abstract

The feed drive system is a major heat source of machine tools, which results in considerable thermal drift at the tool. Therefore, there is a need to establish a scientific and systematic model that can be used to predict the temperature distribution of the feed drive system. In this research, considering the thermal contact resistance between the bearing and its housing, an integrated thermal model has been developed by the aid of the finite-element method to analyse the temperature distribution of a ball screw feed drive system, in particular the theoretical determination of power losses caused by the friction in ball screw pair, rolling bearings, and guide ways. Thermal boundary conditions including the convective heat transfer coefficients and heat flux have been obtained using the Fourier's law. Results reveal that the ball screw shaft surface has a uniform temperature rise of 4.2 °C under a given condition. The temperature rise agrees with the data obtained by an infrared thermometer.