| 摘要 |
A noise silencer for an internal combustion engine has a hollow pipe serving as an air intake for the internal combustion engine and having a length L which is an even submultiple of the wavelength at the lowest of a range of noise frequencies from the internal combustion engine which are to be attenuated. The hollow pipe attenuates noise at the lowest frequency and at certain other frequencies throughout the range. Intervening frequencies are attenuated by at least one expansion chamber coupled to the pipe and having extended inlets and outlets the lengths of which are even submultiples of L. In certain preferred arrangements of the silencer the hollow pipe extends into one expansion chamber forming an extended outlet, a second hollow pipe extends between and within the expansion chamber and a second expansion chamber forming an extended inlet and an extended outlet and a third hollow pipe extends into the second expansion chamber from the internal combustion engine to form an extended inlet. The extended inlets and outlets have lengths equal to L/2, L/4, L/8 and L/16.
|
