Exhaust Gas Purification Device

Abstract

An exhaust gas purification device (101, 102, 103) having a DPF (33) provided in an exhaust system (30) of an internal combustion engine. The device has one or more sound pressure measurement means (8F, 8R) for measuring exhaust sound pressure and calculation means (10) for calculating the amount of PM accumulation based on the exhaust sound pressure measured. On the upstream side of the DPF (33) are arranged exhaust gas temperature measurement means (36) and exhaust gas temperature raising means (34). The exhaust gas temperature raising means (34) is activated when the amount of PM accumulation calculated by the calculation means (10) is higher than a preset default and at the same time when the exhaust gas temperature measured by the exhaust temperature measurement means (36) is lower than a lower limit of a temperature region in which the DPF (33) can be regenerated.

Dependencies are inferred from the claim text.