Patent ID: 8955641
Filing Date: 2015-02-17
Classification: F01N,F02D

Abstract:
1. A vehicle exhaust system comprising: a first resonator having a first inlet and a first outlet; a second resonator positioned downstream of the first resonator, wherein the second resonator has a housing that extends from a first housing end to second housing end to define a housing center axis, and wherein the housing defines a single chamber with an internal cavity having a second inlet and a second outlet, the internal cavity being packed with a high frequency absorption material; a pipe mounted within the internal cavity and extending from the second inlet to the second outlet along a pipe center axis that is offset from the housing center axis, and wherein the pipe includes at least one non-perforated pipe length located within the internal cavity; an inter-pipe connecting the first outlet with the second inlet, wherein the inter-pipe comprises a sole exhaust gas flow path between the first outlet and the second inlet; and a passive valve mounted within the inter-pipe, the passive valve being mounted within the inter-pipe at a predetermined fixed distance from the second inlet of the second resonator.