| 摘要 |
PURPOSE: To decrease the HC discharging amount by setting the HC purifying starting time by an HC purifying second catalytic converter connected to a first catalytic converter through an exhaust pipe to the specified time. CONSTITUTION: An exhaust manifold 2 is connected to an engine 1, a first catalytic converter 31 is connected to the exhaust manifold 2, and a second catalytic converter 32 is connected to the first catalytic converter 31 through an exhaust pipe 4. The HC purifying starting time by the second catalytic converter 32 is set to the time between the HC adsorption completing time of the second catalytic converter 32 and the HC separation completing time. When the HC purifying starting time by the second catalytic converter 32 is set as described above, the HC discharging amount in the CT time of the FTP mode can be decreased by the collaboration of the first and second catalytic converters 31 , 32 . The whole HC purifying ratio can be improved to 98.2%. |
