| 摘要 |
PURPOSE:To reliably decrease discharge of unburnt alcohol and aldehyde to the atmosphere when the temperature of exhaust gas is low such as when an engine is started. CONSTITUTION:A catalytic converter 14 is provided on an exhaust pipe 13 of an engine 11 taking alcohol as fuel, and an adsorbent case 18 is provided on a bypass pipe 17 connected to the exhaust pipe after detouring the converter. Two inlet side dampers 21, 22 for opening and closing the exhaust pipe and the bypass pipe are respectively provided on the exhaust pipe and the bypass pipe on the exhaust gas upstream side from the converter and the case, and an outlet side damper 23 for opening and closing the bypass pipe is provided on the bypass pipe in the exhaust gas downstream from the case. An backwash means 24 connected to the bypass pipe between the case and the outlet side damper is so constituted as to inject compressed air into the case. A controller 32 controls the inlet side dampers, the outlet side damper, and the backwash means on the basis of the detected output of the temperature sensor 31 for detecting the temperature of exhaust gas in the exhaust pipe. |
