The invention relates to a centrifugal separator with a rotor having a separation chamber, a stack of frusto-conical separation discs arranged spaced from each other in the separation chamber coaxially with the rotor, and means defining centrally in the stack of separation discs radially inside thereof...http://www.google.fr/patents/US5052996?utm_source=gb-gplus-shareBrevet US5052996 - Centrifugal separator
