Image Number 5 for United States Patent #6164066.
A muffler for an internal combustion engine has a vertically elongated expansion chamber into which an exhaust gas from the exhaust port of internal combustion engine is introduced. The expansion chamber is separated level-wise into a first expansion chamber and a second expansion chamber by a partition plate. An exhaust emission purifier formed of an oxidation catalyst is attached to the partition plate, thereby allowing the exhaust gas ejected from the exhaust port to be introduced into the second expansion chamber from the first expansion chamber via the exhaust emission purifier. The exhaust emission purifier is spaced apart from the exhaust port by a predetermined distance in a direction orthogonal to an ejecting direction of the exhaust gas.