Abstract: An oil separator for use in the crankcase of an internal combustion engine. A rotatable shaft is located in the crankcase and a case lead-in is sealably fixed to the crankcase and concentric to the shaft. A flat filter disk has one face which abuts the case lead-in and an opposite face which is directly secured to the shaft, so that the filter disk rotates with the shaft. Crankcase gasses flow through the filter disk and the filtered gas flows out an opening defined by the case lead-in. The case lead-in may have a flange secured to a connecting piece which passes through a crankcase wall. A draining edge on the outer surface of the case-lead-in prevents oil from contacting the filter when the shaft is at rest.

Abstract: The invention relates to an oil separator, in particular for application in a crankcase breather for an internal combustion engine, with a filter disc (1), fitted to a driven shaft (2). Gases from the crankcase pas through the filter disc (1). Oil and soot particles adhering to the filter disc (1) are spun off the turning filter disc (1).