External arrangement for damping sounds in a pipe system

Abstract

A device for sound suppression in a channel system for flowing gases or air, particularly an exhaust system or intake system in an internal combustion engine, includes at least one channel which is in communication with two volumes or apertures, wherein standing sound waves arise in the channel. One of the two volumes or apertures can be in the form of a main silencer or a filter housing while the other volume of aperture is in the form of a smaller silencer or an inlet pipe. The pipe, which may be in the form of a volume space, has one end, an inlet opening, in acoustical communication with the channel, while an opposite end is wholly or partly closed against the environment. The pipe is located outside the channel and an acoustic permeable filter is provided in the region near the inlet opening of the pipe. The filter has a flow resistance within the interval 5 Ns/m.sup.3 -2000 Ns/m.sup.3, preferably within the interval 30-300 Ns/m.sup.3.

Dependencies are inferred from the claim text.