Novel aerostatic bearings with hermetically squeeze film dampers for the improvement of stability: Theoretical and experimental investigations

Due to the advantages of low friction, high accuracy, and pollution-free characteristics, aerostatic bearings are widely used in precision and ultra-precision equipment machines. In order to improve the stability, this paper proposes a novel aerostatic bearing with damper modules to suppress the vibration on the bearing surface. A hermetically squeeze film damper (HSFD) constructed by sheet damper module (SDM) is applied to aerostatic bearings for acquiring good stability. The appropriate stiffness range of HSFDs can be obtained for meeting different air film thicknesses and excitation frequencies by theoretical calculations. Various stiffness and damping characteristics can be acquired by adjusting the thickness of sheets in SDMs. In addition, an experimental device is established to identify the stiffness and damping behavior of dampers. In order to further gain insight to evaluate the performance of bearings, a simple test rig has also been set up to measure the vibration characteristics. Experimental results reveal that the damper concept yields high viscous damping characteristics an order of magnitude larger than aerostatic bearing without dampers, which leads to the vibration amplitude be obviously suppressed. The proposed aerostatic bearings with HSFDs can provide a better performance on damping and stability.