| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an intake air system of an engine for a vehicle, which contributes to the sound making for making a sound which a driver hears in driving in a cabin be favorable. <P>SOLUTION: An intake air manifold 11 is comprised of a first divided case part 18 made of aluminum, and second and third divided cases 19, 20 made of resin. The first divided part 18 forms a downstream side manifold connected to an intake air port of a cylinder head 6a, the second divided case part 19 an upstream side manifold, and the third divided case part 20 a surge tank 21. A flat main wall surface 20c facing a cylinder block 6b of the surge tank 21 is provided with substantially uniform wall thickness. The main wall surface 20c diaphragm-vibrates by intake air pulsation to produce sound. The radiation sound is emitted into an engine room 4 through a radiation sound passing hole 35 formed in the first divided case part 18 and penetrated vertically. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
