| 摘要 |
PURPOSE:To reduce the formation of HC, smoke, etc. by jetting-out air from an air injection valve at the time where an exhaust valve is closed in expansion cycle, thus permitting recombustion of exhaust gas, in an engine equipped with the air injection valve in a combustion chamber. CONSTITUTION:In an engine in which the primary and the secondary intake ports 13 and 14 and an exhaust port 15 which are opened to the combustion chamber 7 of each cylinder are opened and closed by the primary and the secondary side intake valves 16 and 17 and an exhaust valve 18, and a spark plug 20, fuel injection valve 21, and an air injection valve 22 are arranged, fuel injection is carried-out from the fuel injection valve 21 at a prescribed time in the former half of intake cycle, in highly loaded state. At the same time, air injection is carried-out from the air injection valve 22. After the swirl in the combustion chamber 7 is strengthened by opening a swirl adjusting valve 10 in the secondary intake passage 9, the spark plug 20 is operated. Then, air is jetted-out form the air injection valve immediately before the opening of the exhaust valve 18 in the latter half of expansion cycle, and exhaust gas is recombusted. |
