摘要 |
A device for purifying exhaust gas of a diesel engine includes a first continuous regeneration type diesel particulate filter (DPF) disposed in the exhaust gas passage of the engine, a second continuous regeneration type DPF having a capacity smaller than the capacity of the first continuous regeneration type DPF and disposed in the exhaust gas passage on the upstream side of the first continuous regeneration type DPF, a by-path surrounding the outer peripheral portion of the second continuous regeneration type DPF, a control valve for opening and closing the by-path, an exhaust gas temperature region-detector for detecting the exhaust gas temperature region of the engine, and a controller for controlling the control valve so as to close the by-path when the exhaust gas temperature region of the engine is in a low temperature region, lower than a predetermined temperature. |