Patent ID: RE39704

Claim:
A centrifugal separator comprising a housing, axle means extending along the housing substantially vertically and defining a rotation axis, a rotor rotatable about the rotation axis about said axle means and including an upper bush and a lower bush at respective upper and lower ends of said axle means, said upper bush and said lower bush each surrounding the axle means defining a journal bearing, and each being exposed to constructed to receive lubricant supplied to the rotor such that allowing lubricant can to pass between said upper bush and said lower bush and said axle means to form therein a film, at least one of said upper bush and said lower bush providing weight thrust bearing means operable to support the weight of the rotor, at least during wind-down, the weight thrust bearing means comprising at least one portion of said axle means tapering from a lower region of greater diameter to an upper region of lesser diameter and said at least one of said upper bush and said lower bush surrounding the portion conforming to the taper and defining a combined journal and thrust bearing whereby the rotor carried by the thrust bearing is centered with respect to the axle means and supported both radially and axially , wherein the rotor includes an upper wall and a lower wall, the upper wall having an upper aperture and the lower wall having a lower aperture, wherein the upper bush is disposed within the upper aperture and the lower bush is disposed within the lower aperture, wherein the upper wall and upper bush and the lower wall and lower bush define a container for receiving a pressurized fluid, wherein the lower bush has a greater inner diameter than the upper bush, and wherein, when the container is filled with a pressurized fluid, the force created by the pressurized fluid and acting on the upper wall and upper bush is greater than the force created by the pressurized fluid and acting on the lower wall and lower bush because of the difference in inner diameter between the lower and upper bushes, thereby pushing the rotor upwards .