Scroll compressor with plural discharge flow paths - U.S. Patent 4,854,831
A high side hermetic scroll compressor passes the discharge gas along the interior of the shell and is thereby cooled prior to being subjected to a centrifugal separation to remove the oil before being discharged from the compressor. The separated oil is returned to the sump via a fluid path isolated from the discharge gas.
Etemad, Shahrokh; Yannascoli, Donald; and Hatzikazakis, Michael, "Scroll compressor with plural discharge flow paths - U.S. Patent 4,854,831" (1989). Engineering Faculty Publications. 21.
Etemad, Shahrokh, Donald Yannascoli, and Michael Hatzikazakis. "Scroll compressor with plural discharge flow paths." U.S. Patent 4,854,831, issued August 8, 1989