Abstract: A vane-type variable displacement pump is controlled by a first stage servo-valve. The servo-valve is controlled by a second stage which may optionally include devices which provide any of several desired control effects.

Abstract: The casing of a pump defines a threaded hole into which is inserted an outer block for reacting radially directed forces transmitted by a second inner block from a movable, pressurized cam ring surrounding the pump rotor. The blocks have mutually parallel mating surfaces arranged generally parallel to a plane tangential to the ring. Onto one of such surfaces is bonded an anti-friction bearing material, such as a woven fabric or metal, to facilitate sliding action between them. The eccentric position of the cam ring is partly established by the action of system pressure acting on control pistons while the guided motion of the inner block further positions the ring to optimal adjustments made to the outer block.

Abstract: A series of conveyor idler roll shafts in end-to-end relation supported by bearings provides a pressurized chamber for the flow of grease or oil to the bearings from a reservoir, which is capable of pumping the lubricant into the axial bore of each shaft. Small, radially directed holes connect the shaft bores to the bearings by providing a restricted passage having across it a suitable pressure drop capable of allowing lubricant to flow in sufficient quantities to each bearing regardless of its distance from the reservoir pressure source. Adjacent shaft ends are connected with a resilient cylindrical tubular coupler to provide the requisite flow passage continuity. A labyrinth seal provides a continuous path for lubricant to flow through the bearings, the seal and ultimately to the exterior of the system, where its appearance is visible and indicative of adequate lubricant flow to each bearing along the shaft assembly.