To reduce the rate of smoke (black smoke) discharged at a stretch at the time of starting and accelerating of a vehicle in which a diesel engine, a cylinder direct injection type gasoline engine, and the like are mounted.
Soot in combustion gas (exhaust gas) is stuck on a wall surface of a combustion chamber, an exhaust port, and the like, it is discharged at the time of starting and accelerating, and it becomes smoke. An accumulation detecting means 13 is arranged for monitoring a part where the soot is easily accumulated, a light transmittance and of exhaust gas and a rate of accumulated soot are detected, and soot accumulation is judged by comparing with a prescribed value by the means 13 such as an electric control unite (an ECU) 14. When an indication that the soot is accumulated is detected, for example, an opening of a cooling water control valve 16 arranged in a flow passage for cooling water of the accumulation part is reduced, and a temperature of the wall surface of the accumulation part is increased so as to suppress accumulation of the soot. Such means for suppressing accumulation of the soot is not only provided, but also means for promoting separation of the accumulated soot, and means for suppress separation of the soot are provided.
OMICHI SHIGEKI
OYAMA NAOHISA
INOHARA TAKAYUKI
SUGIYAMA TOSHIHISA
TOYOTA MOTOR CORP