Time-varying thermoelastic coupling analysis of heat source of ball screw feed drive system

The internal contact state of the ball screw nut pair will affect its heat source strength, and the heat source will further affect the contact state until a certain equilibrium is reached. At present, the research on the time-varying characteristics of the heat source in the ball screw nut pair has not obtained the interaction law between the structure and thermal effects. To solve this problem, this paper proposes a thermoelastic coupling analysis method for the time-varying characteristics of the heat source. A thermoelastic coupling model for the heat source is established, and a contact deformation analysis method based on the plane strain model is proposed. The variation law of the contact deformation between the ball and raceway under thermal influence is studied. An experimental verification method for the thermoelastic variation law of the heat source is designed to demonstrate the compensation principle of thermal deformation on elastic deformation. The results indicate that when considering thermal effects, the contact relationship between the ball and raceway undergoes four stages from the initial unloaded state to the final stable state, namely the unloaded stage, the working load stage, the thermal load stage, and the stable stage. The strength of the ball screw nut pair heat source shows an oscillating decrease. Under specific conditions, thermal deformation has a compensating effect on contact deformation. And the thermoelastic coupling effect of the ball screw nut pair will have an impact on the preheating time of the ball screw feed system.