| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an exhaust device for an internal combustion engine which surely suppresses increase in sound pressure level due to air-column resonance of a tail pipe by a simple construction, while reducing the increase in weight and the increase in manufacturing costs. <P>SOLUTION: The exhaust device for the internal combustion engine includes the tail pipe 27 having a downstream open end 27b on the downstream side in an exhaust direction; an oscillating valve 40 having an oscillating shaft 41 fixed to an upper part of the tail pipe 27, and having a valve body 42 that oscillates around the oscillating shaft 41 so as to change the dimension of the passage cross-sectional area of the tail pipe 27; and a flapping-suppression valve 50 having an oscillating shaft 51 fixed to an upper part of an exhaust pipe so as to be separated from the oscillating shaft 41 in the extending direction of the tail pipe 27, and having a valve body 52 that oscillates around the oscillating shaft 51 so as to change the dimension of the passage cross-sectional area of the tail pipe 27. The oscillation cycle of the oscillating valve 40 upon receipt of an exhaust flow differs from the oscillation cycle of the flapping-suppression valve 50. <P>COPYRIGHT: (C)2011,JPO&INPIT |
