초록 ▼

An exhaust system for a multi-cylinder internal combustion engine has at least two exhaust valves per cylinder. A first exhaust valve in each cylinder is connected to a first catalyst, and a second exhaust valve in each cylinder is connected to a second catalyst which opens out upstream of the first

An exhaust system for a multi-cylinder internal combustion engine has at least two exhaust valves per cylinder. A first exhaust valve in each cylinder is connected to a first catalyst, and a second exhaust valve in each cylinder is connected to a second catalyst which opens out upstream of the first catalyst. The first exhaust valves or their outlets are kept closed during a starting phase of the engine, so that, during the starting phase, all the exhaust gases first pass through the second catalyst which is smaller than the first catalyst and is positioned closer than the latter to the engine.

대표청구항 ▼

1. Exhaust system for a multi-cylinder internal combustion engine comprising:a first larger catalyst connected to the engine, and a second, smaller catalyst also connected to the engine, said second catalyst discharging into an exhaust pipe upstream of the first catalyst so that, during a starting p

1. Exhaust system for a multi-cylinder internal combustion engine comprising:a first larger catalyst connected to the engine, and a second, smaller catalyst also connected to the engine, said second catalyst discharging into an exhaust pipe upstream of the first catalyst so that, during a starting phase of the engine, all the exhaust gases pass through the second catalyst before they reach the first catalyst, at least one first exhaust valve in each cylinder is connected to a first exhaust manifold, which in turn is connected to the first catalyst via an exhaust-gas turbine in a turbo compressor for supercharging the engine, at least one second exhaust valve in each cylinder is connected to a second exhaust manifold, which is connected to the second catalyst, that opens into the exhaust pipe between the turbine outlet and the first catalyst, the first exhaust valves are arranged to be closed during the starting phase.