Fluid thrust bearing for indicating instruments and the like

Abstract

The present invention is a novel fluid thrust bearing system and method for assembling the same. When used in an indicating instrument, the fluid thrust bearing of the present invention reduces the number of necessary parts and simplifies assembly when compared to the prior art. A rotatable element is disposed in a close-fitting cavity so as to define a small gap between the element and the cavity walls, and a fluid is disposed in that gap to the substantial exclusion of air. The fluid damps the rotational movement of the rotatable element. In addition, adhesive forces among the fluid, rotatable element, and cavity walls and cohesive forces within the fluid help maintain the rotatable element in the cavity. Moreover, due to the substantial exclusion of air in the gap, when an axial separating force is applied between the rotatable element and the cavity walls, the resultant tensile stress of the fluid causes a slight stretching of the fluid and creates a negative (vacuum) pressure further preventing the rotatable element from moving axially out of the cavity.

Dependencies are inferred from the claim text.