Abstract: A centrifugal air-oil separator for separating liquid particles from gases containing the liquid particles includes a substantially cylindrical air-oil separation chamber and a substantially conical liquid discharge chamber which are integrated with each other and are horizontally disposed, and an air-oil separation plate disposed between a gas supply port communicating with the air-oil separation chamber and a gas discharge port communicating with the liquid discharge chamber. A liquid discharge port is provided at a lowest portion between a largest-diameter portion of the liquid discharge chamber and the air-oil separation plate, and the liquid discharge port is covered thereabove with a reverse flow prevention wall. A strong swirl flow is generated in the air-oil separation chamber by the action of the air-oil separation plate to thereby enhance the liquid separation effect, and the reverse flow of liquid from the liquid discharge port to the liquid discharge chamber can be prevented.

Abstract: A PCV valve is incorporated in the interior of a centrifugal oil mist separator which is provided integrally on a head cover of an engine. The centrifugal oil mist separator comprises an upstream-side separation chamber including a blow-by gas inlet port and a downstream-side separation chamber to which a blow-by gas outlet port and an oil discharge hole open, and an oil separation plate is disposed such that a communication between the blow-by gas inlet port and the blow-by gas outlet port is cut off. The oil separator plat is provided at a distal end of a protruding portion which integrally extends from a valve seat of the PCV valve, the protruding portion and the oil separation plate functioning to intensify a swirl flow in the upstream-side separation chamber.

Abstract: A centrifugal air-oil separator for separating liquid particles from gases containing the liquid particles includes a substantially cylindrical air-oil separation chamber and a substantially conical liquid discharge chamber which are integrated with each other and are horizontally disposed, and an air-oil separation plate disposed between a gas supply port communicating with the air-oil separation chamber and a gas discharge port communicating with the liquid discharge chamber. A liquid discharge port is provided at a lowest portion between a largest-diameter portion of the liquid discharge chamber and the air-oil separation plate, and the liquid discharge port is covered thereabove with a reverse flow prevention wall. A strong swirl flow is generated in the air-oil separation chamber by the action of the air-oil separation plate to thereby enhance the liquid separation effect, and the reverse flow of liquid from the liquid discharge port to the liquid discharge chamber can be prevented.

Abstract: A PCV valve is incorporated in the interior of a centrifugal oil mist separator which is provided integrally on a head cover of an engine. The centrifugal oil mist separator comprises an upstream-side separation chamber including a blow-by gas inlet port and a downstream-side separation chamber to which a blow-by gas outlet port and an oil discharge hole open, and an oil separation plate is disposed such that a communication between the blow-by gas inlet port and the blow-by gas outlet port is cut off. The oil separator plat is provided at a distal end of a protruding portion which integrally extends from a valve seat of the PCV valve, the protruding portion and the oil separation plate functioning to intensify a swirl flow in the upstream-side separation chamber.