Patent ID: 7380635
Filing Date: 2008-06-03
Classification: F01N

Abstract:
1. An interference-based exhaust noise attenuation device for exhaust flow from an internal combustion engine that generates compressive waves in the exhaust flow, comprising: at least three paths including at least a direct path for the exhaust flow and at least two looped paths for the exhaust flow, with volumes of the direct path and the looped paths differing by an amount that results in a staggered rearrangement of the compressive waves in the paths, and with the looped paths looping on opposite sides of the direct path from each other; a splitter that splits the exhaust flow into at least the three paths; and a merger that merges the exhaust flow from at least the three paths; wherein when the exhaust flow from the direct path and the looped paths are merged, at least some noise cancellation occurs due to the staggered rearrangement caused by the differing volumes between the direct path and the looped paths.