Patent ID: 6662554
Filing Date: 2003-12-16
Classification: F01N,Y10T

Abstract:
An exhaust system for a combine comprising;an internal combustion engine configured to drive the combine on a roadway at roadway speeds and in a field at harvesting speeds; an exhaust pipe from the internal combustion engine; a muffler flow-connected to said exhaust pipe and arranged to direct exhaust gas to atmosphere; a bypass exhaust path that is flow-connected to said exhaust pipe, said bypass exhaust path arranged to direct exhaust gas around said muffler to atmosphere; a valve arranged between said exhaust pipe and said bypass, said valve operable to close said bypass exhaust path during operation of said combine at roadway speeds to increase exhaust system flow restriction and sound attenuation, and operable to at least partially open said bypass exhaust path when operating said combine at harvesting speeds to decrease exhaust system flow restriction and sound attenuation.