SUCTION DEVICE OF ENGINE

PURPOSE:To form a strong swirl in the combustion chamber over a relatively wide range of low load operating area by locating a main intake air path so that its center axis deviates toward the side of an intake air port connected to an auxiliary intake air path. CONSTITUTION:In a low load area where a closing valve 18 is closed, all the intake air passing through a main intake air path 11 is led to an auxiliary intake air path 20 from an opening 19 and enters the combustion chamber 4, forming a strong swirl. In a load area where the closing valve 18 begins to open, the intake air stream of the main air path 11 begins to flow into the branch intake air paths 15, 16, and the flow rate of intake air passing through the auxiliary intake air path 20 is reduced. For the main intake air path 11, its center axis 11a arranged to deviate toward the side of the first intake air port 5. The intake air stream reaching the 1st intake air port 5 from the 1st branch intake air path 15 becomes larger than the intake air stream reaching the 2nd intake air port 6 from the 2nd branch intake air path 16. The intake air stream reaching the 1st intake air port 5 from the 1st branch intake air path joins the intake air stream reaching the 1st intake air port 5 passing through the auxiliary intake air path 20.