Patent ID: 7503171
Filing Date: 2009-03-17
Classification: F01N

Abstract:
1. An exhaust system for an internal combustion engine having a plurality cylinders, comprising: a plurality of exhaust branch passages that are each in communication with at least one of the cylinders; an intermediate exhaust pipe section forming a passage that is in communication with the exhaust branch passages, wherein the intermediate exhaust pipe section has an axis generally curved in an exhaust flow direction; a partition plate provided in the intermediate exhaust pipe section, wherein the partition plate is curved to generally correspond to the axis of the intermediate exhaust pipe section, wherein the partition plate separates the passage into a first merged flow path that is in communication with at least two exhaust branch passages and a second merged flow path that is in communication with at least two other exhaust branch passages; and a downstream pipe section which is connected to the intermediate exhaust pipe section and forms a merged passage that is communication with the first and second merged flow paths; and wherein the partition plate has a surface with a first projection projecting from the surface into the first merged flow path, and wherein the first projection extends along the surface of the partition plate in a direction that is substantially perpendicular to the direction of exhaust flow.