Research on the Rotational Accuracy of Aerostatic Spindle Under Variable Load Conditions

Abstract

This study aimed to study the influence of variable load conditions on the rotational accuracy of the aerostatic spindle. The dynamic model of aerostatic spindle was established considering the gravity of the spindle, nonlinear air film force, and external applied loads. By solving the dynamic model, the motion trajectory of the spindle axis was obtained. Finally, a quantitative explanation was provided for the rotational accuracy laws of the aerostatic spindle. As the speed and eccentricity of the spindle increase, the vibration of the spindle in the x and y directions gradually increased, and the rotational accuracy of the spindle decreased. The periodic load of simulating cutting load was superimposed on the spindle, which increased the amplitude of spindle vibration and reduced the rotational accuracy of the spindle, but did not affect the balance position of the spindle. The impact load changed the balance position of the spindle without generating rotational errors.