Patent ID: 7080637
Filing Date: 2006-07-25
Classification: F02M,Y02T

Abstract:
1. A crankcase of an internal combustion engine, comprising: a blow-by gas passage formed inside a crankcase and configured to discharge blow-by gas inside a crankcase to a top of the crankcase; an oil drain passage formed inside the crankcase that discharges oil collected from the top of a crankcase into the crankcase, wherein said blow-by gas passage and said oil drain passage are interconnected with each other inside the crankcase, and an expansion chamber formed between said blow-by gas passage and said oil drain passage in an area where said passages are interconnected; wherein said blow-by gas passage is formed so as to pass through a certain section of said expansion chamber; said oil drain passage is formed so as to pass by an end of said expansion chamber that is located in a flow direction of said blow-by gas; and said expansion chamber is formed so as to establish a downward slope in the flow direction of said blow-by gas.