Dynamic Characteristics of Aerostatic Porous Journal Bearings

Abstract

Aerostatic porous journal bearings are very suitable for precision devices such as ultra-precision machine tools and precision measuring equipment. However, it is said that aerostatic porous bearings are prone to cause pneumatic hammer instability, unless the surface restricted layer is formed on the bearing surface. This paper theoretically investigates the dynamic characteristics of aerostatic porous journal bearings with a surface restricted layer. In addition, the influences of various design parameters on the dynamic characteristics are discussed and the effects of the surface restricted layer on pneumatic hammer instability are clarified.