Abstract: A fluid-powered rotary motor, and method of operating the same. Pressured fluid is introduced to the annular clearance between a rotor and a second member, and reaches an outlet by travelling circumferentially within that clearance. The direction of motion of the fluid on entering the clearance is substantially tangential relative to the rotor, so as to avoid any substantial jet impingement of the fluid upon the rotor, and so that the rotor is driven substantially wholly by the hydrodynamic viscous drag action of the fluid upon it. Methods of profiling the rotor surface are disclosed which enhance the surface area over which the viscous drag action can be effected.

Abstract: A fluid bearing in which parts of the bearing land are free to move relative to the bearing member on which they are mounted, so that in use the speed of the relative movement of the two confronting surfaces that define the bearing clearance is less than the speed of relative movement of the bearing members themselves. This reduces the power losses due to shearing effects within the thin film of fluid continuously passing through the bearing clearance in contact with these confronting surfaces. The invention applies particularly to rotary bearings of journal and end-thrust type, in which the moving lands may be ring-shaped units, mounted for rotation about the bearing axis and supported by relatively friction-free bearings--for instance gas bearings--on the bearing member in which the bearing recess is formed.

Abstract: A fluid bearing of the type whereby a fluid film is created which separates the confronting surfaces of two bearing members in use, and in which the fluid is supplied from a recess formed in one of those surfaces. Fluid shear resistance, resulting from fluid circulation set up within the recess by the relative movement of the two bearing members, is diminished by providing the recess fluid with a circulation path whereby the effect of the circulation within the path is to set up a negative pressure gradient in the fluid lying between the leading and trailing ends of the recess and adjacent the surface of the other bearing member. The path may lie external to the recess itself, or may be created within the recess by a baffle which may be movable so that the gradient may be varied to match changes in operating conditions.

Abstract: A hydrostatic bearing with structural features to improve the harmony between hydrostatic and hydrodynamic forces set up in the bearing fluid, and to diminish the harmful effects of hydrodynamic forces when there is relative motion between the bearing members. These features may comprise channels in the bearing land to maintain transverse hydrostatic fluid flow beneath the land despite longitudinal dynamic forces, longitudinal channels in the bearing surfaces to diminish dynamic friction without unduly diminishing the resistance to hydrostatic fluid flow across these channels, and means to guide fluid recirculation within the bearing recess so as to avoid shearing contact between oppositely-moving streams of fluid within it.