A built-in oil-gas separating device includes a secondary oil-gas separator, a main oil-gas separator, an oil-gas barrel, an oil-gas barrel liner, and an oil-gas barrel lid. The secondary oil-gas separator is disposed inside the main oil-gas separator. The oil-gas barrel liner is disposed around the main oil-gas separator. The oil-gas barrel liner is disposed inside the oil-gas barrel. Upper end faces of the secondary oil-gas separator and the main oil-gas separator are sealingly connected to a lower end face of the oil-gas barrel lid. The oil-gas barrel lid has a gas discharging hole located above the secondary oil-gas separator. The gas discharging hole is sealingly connected to a pressure maintenance valve. The compressed air obtained by the double layer filtration structure of the present disclosure can achieve a 40% reduction in oil content as compared with the compressed air obtained by the ordinary single layer filtration structure.

A flow accelerating ventilation type head cover may include a baffle separating a lower space which is opened such that blow-by gas containing an oil particle generated from an engine is collected thereto and an upper space which is closed such that the blow-by gas is flowed out to an outside of the engine and having a baffle passage communicating the lower space with the upper space such that the blow-by gas is exhausted from the lower space to the upper space therethrough, and a flow accelerating member being coupled with the baffle passage and being positioned in the upper space so as to accelerate a flow speed of the blow-by gas passing through the baffle passage and thus separate the oil particle by collision effect of impacting the oil particle with each other in the upper space.

A flow accelerating ventilation type head cover may include a baffle separating a lower space which is opened such that blow-by gas containing an oil particle generated from an engine is collected thereto and an upper space which is closed such that the blow-by gas is flowed out to an outside of the engine and having a baffle passage communicating the lower space with the upper space such that the blow-by gas is exhausted from the lower space to the upper space therethrough, and a flow accelerating member being coupled with the baffle passage and being positioned in the upper space so as to accelerate a flow speed of the blow-by gas passing through the baffle passage and thus separate the oil particle by collision effect of impacting the oil particle with each other in the upper space.

An oil separator is provided with a case that has an air inlet and a plurality of expansion chambers formed within the case. Air that contains oil is introduced into the case via the inlet and caused to strike a impingement plate to thereby separate the oil from the introduced air and recover the oil. The transverse cross-sectional area of each expansion chamber is greater than the open area of the inlet. Partition walls with orifice holes formed therein are provided between the expansion chambers.

An oil separator is provided with a case that has an air inlet and a plurality of expansion chambers formed within the case. Air that contains oil is introduced into the case via the inlet and caused to strike a impingement plate to thereby separate the oil from the introduced air and recover the oil. The transverse cross-sectional area of each expansion chamber is greater than the open area of the inlet. Partition walls with orifice holes formed therein are provided between the expansion chambers.

An oil supply apparatus for a vehicle includes: an oil pump that supplies oil in an oil pan that stores the oil circulating in an engine; an oil supply passageway that supplies the oil from the oil pump to a lubricating part and a hydraulic actuating part of the engine; and a bubble separating unit that is provided in the oil supply passageway and separates bubbles contained in the oil.

An oil supply apparatus for a vehicle includes: an oil pump that supplies oil in an oil pan that stores the oil circulating in an engine; an oil supply passageway that supplies the oil from the oil pump to a lubricating part and a hydraulic actuating part of the engine; and a bubble separating unit that is provided in the oil supply passageway and separates bubbles contained in the oil.

An oil separator includes a casing that has an inlet for air and an outlet for air, and an impingement member that is provided inside the casing. Air that contains oil is introduced through the inlet into the casing and caused to strike the impingement member so that the oil is separated from the introduced air and is recovered. The outlet opens in the horizontal direction of the casing. The oil separator further includes an L-shaped elbow member that is attached to the outlet. The elbow member protrudes in the horizontal direction from the outlet and is bent upward.

An internal combustion engine includes an engine block defining a plurality of cylinders each receiving a piston. A crankcase extends from the engine block and supports a crankshaft drivingly connected to the pistons and including a chamber enclosed by a wall portion that defines a first blow-by flow passage and first and second drain passages therethrough. An oil sump mounted to the crankcase. A first oil separator is mounted to the wall of the crankcase in communication with the first blow-by flow passage and the first drain passage and defining a second blow-by flow passage therethrough and a third drain passage extending therethrough in communication with the second drain passage. A second oil separator mounted to the first oil separator in communication with the third drain passage and defining a third blow-by flow passage in communication with the second blow-by flow passage.

Disclosed is an arrangement of a filtering element for a device for purifying gas from the crankcase of an internal combustion engine, which includes: a filtering element mounted so as to rotate about an axis and having an annular filtering medium; a rotor element capable of being part of a rotating system, making it possible to turn the filtering element by way of notches formed on the outer surface of a sleeve. The flanges of the filtering element are attached to one another in an inner space defined by the medium, typically by snap-fitting, using at least one retaining member and an anchor portion engaging with one another with an anti-rotation effect. The anchoring portion is provided with inner projections forming contact surfaces, preferably angular, which are inserted into the notches of the sleeve when the rotor element is inserted into the inner space.