| 摘要 |
PROBLEM TO BE SOLVED: To control emission of HC by making switching to the total area mixture layer when the storage quantity of the evaporated fuel exceeds the prescribed value during the operation by the limited layer in an engine provided with a mixture layer forming means to selectively switch the limited mixture layer and the total mixture layer according to the operational condition. SOLUTION: In a control unit 19 while an engine is in operation, the engine speed, the load, the cooling water temperature, etc., are read to judge the condition of stratification by the limited mixture layer based on the read data. For example, when the engine is operated in the relatively low speed and load, and after warming-up of the engine, it is judged that the condition of stratification of the mixture is established, while the homogeneous mixture layer by the total mixture layer is formed when the condition is not established. When the condition of stratification is established, the estimated value of the quantity of the evaporated fuel stored in a canister 43 is read, and compared with the set level. When the estimated value is smaller, the limited mixture layer is formed. When the estimated value is higher, the pre-mixing combustion is performed by forming homogeneous mixture layer totally in the combustion chamber without performing the stratified combustion when the estimated value is higher.
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