‘Dynastat’ Bearing — a New Hydrodynamic and Hydrostatic Hybrid Bearing

A new type of hybrid bearing has been developed in S.M.T.W. with excellent performances as compared with hydrodynamic or hydrostatic bearing, with their inherent defects eliminated. In this bearing, the hydrostatic effect of axial step bearing is superimposed with hydrodynamic effect of circumferential step bearing. It may be employed in the precision machine tool spindle with the result of high accuracy, good load carrying.capacity and better stability, while its oil supply pressure may be reduced to 1/5 of that of conventional hydrostatic bearings. In this paper the principle, structure and performance of ‘DYNASTAT’ bearing and its applications are presented. Also, the analytical results by finite difference equation and finite element method are presented.