To provide technology enabling more suitable EGR operation which re-circulates a large quantity of EGR gas, while inhibiting excessive rise of pressure difference between an inlet and an outlet of a low pressure EGR passage.
The EGR comprises a turbocharger 6, a low-pressure EGR passage 14, a high-pressure EGR passage 12, and a differential pressure sensor 17. When the differential pressure sensor 17 detects a differential pressure greater than a specified differential pressure during recirculation of EGR gas, the low-pressure EGR passage 14 is used to recirculate a volume of EGR gas equivalent to a differential pressure equal to or smaller than the specified differential pressure, while the high-pressure EGR passage 12 is used to recirculate a remainder of a required flow volume.
COPYRIGHT: (C)2007,JPO&INPIT
NAGAE MASAHIRO
MURATA HIROKI
NAKAYAMA SHIGEKI
ONISHI TOMOMI
Mayuko Wakuda
Kazunobu Sera
Tsutomu Toyama
Takehiko Sekine