Centrifugal filter utilizing a partial vacuum condition to effect reduced air drag on the centrifuge rotor

Abstract

A centrifuge filter for removing soot from engine oil. The centrifuge filter includes a rotor adapted to be rotated inside a centrifuge housing by an electric motor or other means. The rotor preferably includes a reusable aluminum support casing and a disposable plastic cartridge. The plastic cartridge includes a trap with partition walls to prevent wave formation in the rotating liquid contained in the trap. The cartridge includes an annular inlet through its top end, a winding flow path through the cartridge and an outlet at the bottom enc. The centrifuge housing includes an isolated sealed rotor chamber. Using the venturi effect, air is evacuated from the rotor chamber to provide a partial vacuum to reduce air drag on the rotor. Resilient rubber vibration isolators are used to reduce vibrations and engine induced shock loads from reaching the rotating element. A side oil inlet is provided in the cartridge to receive unfiltered oil at a location offset from the axis of rotation. Oil is feed in through the top of the centrifuge cartridge and discharged out the bottom. The rotor is carried by bearings on a stationary central support shaft. Maintenance is performed through a removable lid on the top end of the rotor. A restriction plug is used to control flow into the rotor.