EXHAUST PURIFICATION DEVICE FOR INTERNAL COMBUSTION ENGINE

摘要

Micropore zones ZMI are defined at upstream sides of partition walls 72 of a particulate filter and macropore zones ZMA are defined at downstream sides of partition walls. The pore size of the partition walls at the micropore zones is set so that the particulate matter and the ash can be trapped by the partition walls at the micropore zones, while the pore size of the partition walls at the macropore zones is set so that the ash can pass through the partition walls at the macropore zones. When a quantity of trapped particulate matter is smaller than a limit quantity, control for increasing gas which temporarily increases the flow rate of the gas which flows into the particulate filter in order to remove the ash from the particulate filter, is performed.

主权项

1. An exhaust purification device for an internal combustion engine which arranges a particulate filter for trapping particulate matter which is contained in exhaust gas in an engine exhaust passage, where said particulate filter is provided with alternately arranged exhaust gas inflow passages and exhaust gas outflow passages and porous partition walls which separate these exhaust gas inflow passages and exhaust gas outflow passages from each other, micropore zones are defined at upstream sides of the partition walls, macropore zones are defined at downstream sides of the partition walls, a pore size of the partition walls in the micropore zones is set so that particulate matter and ash can be trapped by the partition walls at the micropore zones, and a pore size of the partition walls in the macropore zones is set so that ash can pass through the partition walls at the macropore zones, characterized in that when a quantity of trapped particulate matter on the particulate filter is smaller than a predetermined limit quantity, control for increasing gas which temporarily increases the flow rate of gas which flows into the particulate filter in order to remove the ash from the particulate filter, is performed.