Novel thermal error control strategy for feed drive mechanisms via sintered core heat pipe-cooled moving nut

In feed drive mechanisms, thermally-induced deformation in the screw-nut pair affects positioning accuracy. Traditional circulating cooling systems regulate screw shaft temperature but fail to address the uneven axial temperature gradient caused by the nut's reciprocating motion, leading to significant positioning errors. To tackle these issues, a novel thermal error control strategy is devised, utilizing a sintered core heat pipe (SCHP) for cooling the moving nut. Specifically, a gas-liquid phase transition model is formulated for the proposed sintered core heat pipe. Furthermore, the heat transfer performance of the sintered core heat pipe is experimentally validated, and a response surface model is constructed to determine its convective heat transfer coefficient. Following this, by integrating into sintered core heat pipe into feed drive mechanisms, the peak temperature of moving nut, thermal equilibrium time, and screw shaft's elongation were measured to be 26.8 °C, 148 min, and 55.1 μm, respectively. The moving nut's peak temperature, thermal equilibrium time, and screw shaft thermal elongation are significantly reduced by 20 %, 28 %, and 23.6 %, respectively. Positioning error reduction in feed drive mechanisms ranges from 74.8 % to 88.7 %. More importantly, the proposed SCHP-cooled strategy is much more effective than traditional circulating cooling system.