US Patent 10550929 Oil lubrication system of transmission case

A lubrication system of a transmission includes a plurality of oil passages formed in an upper portion of a transmission case and supplied with churning oil, a plurality of oil outlets branched from respective oil passages formed in the transmission case and allowing oil supplied from the oil passages to free-fall, and an oil collecting portion formed at an interior of the case wall between the gear case and the motor case. In particular, the oil collecting portion collects oil free-falling from at least one oil outlet branched from at least one oil passage at the gear case, through a through-hole formed at a case wall of the gear case, and then supplies the collected oil to an exterior lubrication portion.