Air injection timed with exhaust release

摘要

Embodiments for injecting air into exhaust ports of an engine are provided. In one example, a multi-cylinder engine method comprises combusting a rich air-fuel mixture, injecting air into a first cylinder's exhaust port and not into a second cylinder's exhaust port during the first cylinder's exhaust stroke, and injecting air into the second cylinder's exhaust port and not into the first cylinder's exhaust port during the second cylinder's exhaust stroke. In this way, injection into each exhaust port may be timed with exhaust release into each exhaust port.

主权项

1. A multi-cylinder engine method, comprising:
combusting a rich air-fuel mixture; rotating a circular disc with a single cut-out opening comprising a circular sector to one or more first positions, the opening in the one or more first positions fluidically connecting a pressurized air supply with a first cylinder's exhaust port and not a second cylinder's exhaust port, and injecting air from the pressurized air supply into the first cylinder's exhaust port and not into the second cylinder's exhaust port during the first cylinder's exhaust stroke; and rotating the circular disc to one or more second positions, the cut-out opening in the one or more second positions fluidically connecting the pressurized air supply with the second cylinder's exhaust port and not the first cylinder's exhaust port, and injecting air from the pressurized air supply into the second cylinder's exhaust port and not into the first cylinder's exhaust port during the second cylinder's exhaust stroke.