关键词: 数控机床进给系统, 角接触球轴承, 热力耦合分析, 热网络法, 时变动态特性

Abstract: The prediction and analysis of thermal mechanics coupling performance of angular contact ball bearings was the key to ensure the working accuracy of machine tools. Based on Hertz contact theory and thermal network method, a dynamic thermal mechanics coupling model of ball screw feed system pair-installed bearings was established under working conditions, the internal lubrication state and the thermal expansion of ball bearings were considered under temperature rise effect, and a numerical calculation method was proposed for dynamic thermal mechanics coupling analysis of bearings. The time-varying laws of internal contact parameters and friction heat generation of the bearings were proved. Results show that the rotational speed and the external load affect the frictional contact characteristics of bearings, and the performance of bearings is significantly affected by the thermodynamics behavior. The dynamic thermal mechanics coupling analysis model proposed herein may effectively predict the contact characteristics of bearings under nonlinear thermal behavior. 

Key words: CNC machine tool feed system, angular contact ball bearing, thermal mechanics coupling analysis, thermal network method, time varying dynamic characteristic