Patent ID: 6860365

Claim:
A system for lubricating the upper bearing supporting a rotatable vertical shaft in a machine or pump comprising an axial bore extending along substantially the length of the shaft and communicating at its lower open end with a reservoir containing lubricating fluid, at least one radial oil hole extending between the axial bore and the upper bearing for the delivery of lubricating fluid thereto, the arrangement being such that centrifugal force generated during rotation of the shaft will draw lubricating fluid from the reservoir upwardly along the axial bore in the form of a thin film and towards the radial oil hole for delivery to the upper bearing, and an air delivery and demisting circuit including an air/lubricating fluid mist chamber communicating with the axial bore via at least one radial port located between the lower open end and the upper bearing, the port having a distal end extending in to the axial bore, at least one air hole extending between the axial bore and the outer cylindrical surface of the vertical shaft at a location above the upper bearing, and an impeller for pumping the air/lubricating fluid mist through the radial port and along the axial bore where the lubricating fluid is separated out by centrifugal force during rotation of the shaft to join the lubricating fluid film extending along the surface of the axial bore, clean air exiting the axial bore via the air hole above the upper bearing.