| 摘要 |
PROBLEM TO BE SOLVED: To reduce fuel consumption by performing the operation in lean by performing the operation in lean to a point where the fuel consumption is minimum, then switching fuel consumption stoichiometrically without changing the gear ratio, increasing the output without changing the gear ratio until the fuel consumption becomes minimum, and changing the gear ratio after the fuel consumption becomes minimum to operate an engine at a target operation point or in its vicinity. SOLUTION: In a lean operation region, operation is performed with a high gear up to a boundary region between the lean and the stoichiometry. In the regions of lean and stoichiometry, the engine torque is retained by lean operation, and the gear ratio is made low gear. That is, the engine rotating speed is increased. At the time of transition to the region with good fuel consumption in lean, with a stepped transmission, the gear ratio is kept constant, and with a continuously variable transmission, the gear ratio is kept within the fluctuation range of ±0.3. The fluctuation of ±0.3 is a range to which a driver does not have a feeling of physical disorder. After reaching the region with good fuel consumption of stoichiometry, the engine torque is kept constant and the gear ratio is made low to increase the coaxial torque. |
