Patent ID: 7210471
Filing Date: 2007-05-01
Classification: F01M,F02M,Y02T

Abstract:
1. A structure of a breather chamber in an internal combustion engine, the engine having a combustion chamber, a crank chamber, an intake passage connected to the combustion chamber, a head cover, and a blow-by gas passage, the blow-by gas passage connecting the crank chamber to the intake passage, thereby sending blow-by gas, which has leaked from the combustion chamber to the crank chamber, to the intake passage, wherein the blow-by gas contains oil, and the breather chamber is located in the blow-by gas passage to separate the oil from the blow-by gas, the structure comprising: a plate-like member disposed in the head cover, the breather chamber being defined over the plate-like member; an auxiliary plate that partitions the interior of the breather chamber into upper and lower spaces communicating at ends thereof with the blow-by gas flowing in a flow direction sequentially through the upper and lower spaces; and a separating plate that is provided in at least one of the upper and lower spaces, wherein the separating plate obstructs the flow of the blow-by gas in the associated space, thereby separating oil from the blow-by gas, wherein the engine has a crankshaft, an intake camshaft, an exhaust camshaft, a transfer belt for transferring rotation of the crankshaft to the intake camshaft and the exhaust camshaft, the head cover for covering the intake camshaft and the exhaust camshaft from above, and an air inlet passage for drawing air outside of the engine to the crank chamber, and wherein the head cover defines a sub-space in which the intake camshaft is located and a sub-space in which the exhaust camshaft is located, wherein one of the sub-spaces is an air stirring down space in which surrounding air is stirred down along with turning of the belt, and part of the air stirring down space that is located in the vicinity of the belt forms part of the air inlet passage.