US Patent 7699029 Crankcase ventilation system with pumped scavenged oil

A crankcase ventilation system for an internal combustion engine has a jet pump suctioning scavenged separated oil from the oil outlet of an air/oil separator and pumping same to the crankcase. The jet pump supplies pumping pressure greater than the pressure differential between the higher pressure crankcase and the lower pressure oil outlet, to overcome such pressure differential and the back flow tendency otherwise caused thereby, and instead cause suctioning of scavenged separated oil from the oil outlet and pumping same to the crankcase.