| 摘要 |
PROBLEM TO BE SOLVED: To provide an exhaust noise-muffling device to be connected to the exhaust system of an engine, which ensures high muffling performance in a low load operation of the engine, and also prevents the output deterioration caused by an exhaust resistance in the high load operation region. SOLUTION: In a muffler body 5, there are provided a first exhaust pipe 21 which always communicates the insides of the muffling chambers 15, 16 and 17 with the atmosphere, and a second exhaust pipe 22 having a control valve Vc which is opened in response to the elevation of exhaust pressure inside the muffling chambers to communicate with the atmosphere. In this case, the portion of the first exhaust pipe 21 from its halfway part to the end opened to the atmosphere is positioned inside the second exhaust pipe 22. |
