Abstract: A micro-contoured surface is formed about a substantial portion of the edge of the end bearing face of each gear tooth of a gear having a plurality of circumferential gear teeth each with an end bearing face for carrying an axial thrust load against a flat housing bearing face or the like. The micro-contoured surface forms a wedge space between the bearing faces which when filled with a fluid establishes a hydro-dynamic film pressure distribution over the entire end bearing face of the gear tooth upon relative motion between the bearing faces.

Abstract: A centrifugal pump has a casing with an impeller cavity in which a shrouded impeller is mounted and with front and rear labyrinth seals associated one with each of the front and rear shrouds of the impeller and located near the inner ends of the shrouds. An additional seal is positioned inwardly of the rear labyrinth seal to substantially seal a space behind the innermost part of the rear shroud and a pump structure is mounted on the impeller to the rear of the rear shroud for pumping fluid from the substantially sealed space to the entrance of a volute surrounding the impeller.

Abstract: A fluid delivery system and, more particularly, a system for delivering fuel to an aircraft engine. A positive displacement pump delivers fuel to the engine and is supplied by an ejector boost pump connected to a fuel tank and having a nozzle supplied with fuel delivered by the fuel pump for drawing fuel from the tank and increasing the pressure of the fuel prior to delivery through interstage components to the inlet of the fuel pump. Valve means responsive to the pressure differential across the nozzle of the ejector boost pump operates to maintain a uniform rate of fuel flow through the nozzle. In certain embodiments of the fluid delivery system, the fuel pump is provided with auxiliary inlets for delivery of fuel to pumping chambers out of communication with the main inlet of the pump for improved operation of the fuel pump and avoidance of problems encountered from the presence of vapor in the fuel.