| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce a pressure loss and flow noise at the open end of a pipe in a muffler without changing the acoustic characteristics of the muffler. <P>SOLUTION: This muffler 1 is arranged in an exhaust passage and reduces pulsation noise of exhaust gas. At least one of the components of the muffler 1 is formed with a plurality of small holes 40 at a predetermined opening rate. The predetermined opening rate is set to such a value that, when a pass limiting frequency determined according to the opening rate represents the upper limit of the frequency of the pulsation noise passed through the small holes 40, the pass limiting frequency is higher than an upper limit within the frequency range of the pulsation noise to be reduced by the muffler 1. <P>COPYRIGHT: (C)2010,JPO&INPIT |
