Improvement of Pneumatic Hammer Instability of Aerostatic Thrust Bearings with Compound Restrictors

Abstract

It is well known that aerostatic bearings with compound restrictors tend to cause pneumatic hammer instability at the optimum bearing clearance for the maximum stiffness. In this paper, the improvement of such an instability in the aerostatic thrust bearings are discussed. An orifice restrictor put in series into an air supply line is used as a stabilizer. The static and dynamic characteristics of aerostatic thrust bearings with this stabilizer are investigated experimentally and theoretically, and the usefulness of this method for improving the stability of this kind of bearings is confirmed. It is consequently found that the proposed method is very efficient in avoiding the pneumatic hammer instability.