| 摘要 |
<p>A secondary air supply control system for internal combustion engine exhaust gas purification systems which comprises a first change-over valve for selectively supplying secondary air from the air pump either to the upstream side of the catalytic converter or to a second change-over valve, an on-off valve and control valve for controlling the switching of the first change-over valve, a second change-over valve for supplying the secondary air from the first change-over valve to the exhaust ports of the engine for discharging into the atmosphere, and a second control valve for controlling the switching action of the second change-over valve, part of the secondary air from the air pump being supplied to the downstream side of the catalytic converter.</p> |
