| 摘要 |
PROBLEM TO BE SOLVED: To prevent increase of NOx discharge while maintaining stratified burning even when crossing a boundary between the adjacent operation zones having different setups of the stratified burning. SOLUTION: This cylinder direct injection type spark ignition engine to perform stratified burning at a lean air-fuel ratio in a predetermined operation zone, is provided with temporary operation at theoretical air-fuel ratio executing means (41, 7) to temporarily execute homogeneous combustion at a theoretical air-fuel ratio when crossing the boundary between the adjacent operation zones in the case that setups of the stratified burning are different in the adjacent operation zones among the predetermined operation zones to perform the stratified burning, and a catalyst (31) to reduce NOx contained in exhaust at the time of homogeneous combustion at the theoretical air-fuel ratio. COPYRIGHT: (C)2004,JPO&NCIPI
|
