| 摘要 |
PROBLEM TO BE SOLVED: To strengthen flowing of combustion gas within a cylinder in a combustion chamber to agitate the combustion gas and enhance combustion efficiency of an engine by improving a combustion state without increasing cost.SOLUTION: An engine 24 comprises: a cylinder block 33 that has a cylinder 47 forming a combustion chamber 46; and a cylinder head 34 that is joined to one end of the cylinder block to form a combustion chamber top portion 51 and that has an intake port 36 for guiding air-fuel mixture to inside of the combustion chamber and the combustion chamber top portion. In an intake system for the engine, the air-fuel mixture comprising air and fuel is supplied to the intake port of the engine through main intake passages 43, 45, and an ISC device 65 is arranged. The ISC device includes a sub intake passage 66, and controls supply amount of the air to the intake port 36. The flow passage cross section of the sub intake passage is made smaller than that of the main intake passage 43, 45, and the sub intake passage has an inlet 66A arranged in the main intake passage and an outlet arranged in the intake port 36. |
