Heat exchangers of multiple cylinder internal combustion engine

Abstract

First heat exchangers (H4, H3, H2) are disposed within an exhaust port (18), within a pre-catalytic device (34), and on the downstream of a main catalytic device (35); the exhaust port (18), the pre-catalytic device (34), and the main catalytic device (35) being provided in each exhaust passage (33) of a multicylinder internal combustion engine. These first heat exchangers (H4, H3, H2) are independently provided for each of the exhaust passages (33), and a second heat exchanger (H1) is disposed in a section where these exhaust passages (33) are combined. Since the first heat exchangers (H4, H3, H2) are disposed on the upstream side of the exhaust passage (33), high heat exchange efficiency can be obtained by high temperature exhaust gas, and, moreover, the occurrence of exhaust interference can be avoided, thereby preventing any decrease in the output of the internal combustion engine. Furthermore, since the second heat exchanger (H1) is disposed in the section where the exhaust passages (33) are combined, the exhaust gas in which pulsations have disappeared as a result of the flows being combined can be made to act on the second heat exchanger (H1), thereby enhancing the heat exchange efficiency.

Dependencies are inferred from the claim text.