To remove a PM more suitably which adheres on an end face of an insulating member installed between a carrier and a case in an EHC when the EHC is used as a three way catalyst.
An air-fuel ratio of exhaust of an internal combustion engine is repeatedly changed into a lean air-fuel ratio and a rich air-fuel ratio, and thereby its average value is maintained in the vicinity of a theoretical air-fuel ratio. While the PM adhering on the end face of the insulating member of the EHC is removed, when a PM adhesion amount is large, the air-fuel ratio during the rich air-fuel ratio is set lower than the case that the PM adhesion amount is small, and furthermore, a period of the rich air-fuel ratio is set shorter or a period of the lean air-fuel ratio is set longer.
| JP5274971 | Vegetable harvester |
| WO/2014/087952 | EXHAUST PURIFICATION SYSTEM OF INTERNAL COMBUSTION ENGINE |
| JP2013002355 | DENITRATION DEVICE |
TAKAGI NAOYA
KUMAGAI NORIAKI
Kazunobu Sera
Akira Hirakawa
Takehiko Sekine
Katsuhiko Imahori
Fuminori Miyashita