Multi-chamber muffler with selective sound absorbent material placement

Abstract

The present invention provides an acoustic muffler for attenuating sound waves of the exhaust gas of an internal combustion engine including a shell, a plurality of walls closing both ends of the shell and dividing an interior of the shell into a plurality of chambers. The plurality of chambers include a first chamber having a sound absorbing material disposed therein. An imperforate pipe extends between the walls of the first chamber. Preferably, the plurality of chambers also include a second and a third chamber communicating with the imperforate pipe. Furthermore, a fourth chamber communicates with the second chamber.