INTERNAL COMBUSTION ENGINE EXHAUST AIR PURIFICATION DEVICE

摘要

An internal combustion engine exhaust air purification device can simultaneously perform filter reproduction and NOx purification while suppressing excessive supply of HC. The exhaust air purification device includes: a first exhaust air purification device for purifying NOx; a second exhaust air purification device which is arranged in series to the first exhaust gas purification device and captures PM; HC supply means which supplies HC to each of the first exhaust gas purification device and the second exhaust gas purification device; and priority decision means which decides which of the HC supply to the first exhaust air purification device or the HC supply to the second exhaust air purification device has a higher priority. When the HC supply request to the first exhaust gas purification device is overlapped by the HC supply request to the second exhaust gas purification device, the HC supply amount to the one having the lower priority is reduced than the case when the HC supply request is not overlapped.