| 摘要 |
<p>The injection of secondary air into the exhaust system of an internal combustion engine (1) equipped with an electrically heated catalyst (EHC) (3) upstream of a catalytic converter (6) using a secondary pump (8) is controlled by use of a dedicated heated oxygen sensor (5) located downstream of the electrically heated catalyst (3) in the exhaust stream from said EHC. The sensor (5) measures the oxygen content in the EHC exhaust stream (4) and sends a signal to a controller (7) which turns on a secondary air pump (8) when the signal from the heated sensor (5) exceeds a pre-selected set point on the controller (7) thereby injecting supplementary air into the exhaust stream from the internal combustion engine (1) to the EHC.</p> |
