| 摘要 |
PROBLEM TO BE SOLVED: To provide an exhaust circulation device of an engine, which can efficiently remove soot deposited on an EGR cooler.SOLUTION: An exhaust circulation device of an engine has an EGR passage 30, an EGR cooler 34, an EGR valve 31, a bypass passage 37, and a bypass valve 38, and a control valve 80 for controlling a flow of exhaust gas is disposed at a position which is upstream of a connection point 37a where the bypass passage 37 is connected to an exhaust passage 20 and is downstream of a connection point 30a where the EGR passage 30 is connected to the exhaust passage. When selecting a DPF regeneration mode, an EGR cooler regeneration mode is previously executed for closing the EGR valve 31 and the control valve 80 and setting the bypass valve 38 at an intermediate opening to return exhaust gas from the EGR passage 30 to the exhaust passage 20 via the bypass passage 37.SELECTED DRAWING: Figure 6 |
