BLOW-BY GAS INLET STRUCTURE OF OIL SEPARATOR FOR INTERNAL COMBUSTION ENGINE

A blow-by gas inlet structure of an oil separator adapted to be placed above a cam chamber of an internal combustion engine, comprises a plate that forms a bottom wall of the oil separator; a blow-by gas inlet opening that is formed in the plate; an oil blocking structure that is provided below the blow-by gas inlet opening in a manner to divide the blow-by gas inlet opening into front and rear inlet openings through which the blow-by gas is led into the oil separator, the front and rear inlet openings being arranged in a first direction; and a transverse rib that is provided on the oil blocking structure and extends in a second direction that is perpendicular to the first direction.