| abstract |
PROBLEM TO BE SOLVED: To provide an exhaust aftertreatment device in which exhaust purification performance is improved by efficiently combining a low temperature type urea SCR catalyst, a high temperature type NOx storage catalyst, and a particulate filter. SOLUTION: A filter (41) with a NOx catalyst comprising a low temperature active type urea SCR catalyst and a particulate filter (DPF) is provided on the exhaust downstream side of a high temperature active type NOx storage catalyst (42), and the exhaust of the NOx storage catalyst is provided. Based on the catalyst temperature information from the temperature detection means (60), the HC supply means (50) provided on the upstream side and the urea supply means (52) provided on the exhaust upstream side of the NOx catalyst filter are controlled by the control means (10, 51, 53). [Selection] Figure 1 |