| 摘要 |
PURPOSE:To effectively reduce the exhaust noise in a wide frequency range by connecting a noise suppressing cylinder which is made of porous material and has the equal inside diameter to a tail tube, at the rear edge of said tube, and installing an outside cylinder, keeping each prescribed peripheral gap from between the outside of the noise suppressing cylinder. CONSTITUTION:A noise suppressing cylinder 7 which is made of the porous material having air vent holes and has a prescribed length is connected to a discharge port 4A at the rear edge of a tail tube 4. An outside cylinder 8 which is made of metal plate and is set a little longer than the noise suppressing cylinder 7 is arranged outside the noise suppressing cylinder 7. Said noise suppressing cylinder 7 is formed to a true circular cylinder having the equal inside diameter to the tail tube 4. While, said outside cylinder 8 is formed to have rectangular section, and a back air layer (A) which has the different length of gap in the vertical and the lateral directions from between the noise suppressing cylinder 6. |
