Exhaust purification device for internal combustion engine

Abstract

Provided is an exhaust purification device for an internal combustion engine, wherein the operation of an internal combustion engine can be prevented from being maintained when a particulate filter is melted. An exhaust purification device (1) for an internal combustion engine (2) is comprised of a particulate filter (10); a downstream-side temperature sensor (20a) which detects a downstream-side exhaust temperature (T1); a filter temperature sensor (20b) which detects a filter temperature (T10); an exhaust differential pressure detection device (21) which calculates an exhaust differential pressure (P(n)) between an upstream-side exhaust pressure (p1) and a downstream-side exhaust pressure (p2) at predetermined time intervals; a notification device (40); and an ECU (30) which controls the internal combustion engine (2). In the exhaust purification device (1), a differential pressure variation (dP) is calculated on the basis of a first exhaust differential pressure (P(n-1)) and a second exhaust differential pressure (P(n)) after the elapse of a predetermined period of time. When the differential pressure variation (dP) is equal to or larger than a reference variation (Ps) or the downstream-side exhaust temperature (T1) remains equal to or larger than an exhaust reference temperature (T1s) for a period of time equal to or longer than a reference period of time (ts), a demand to stop operating the internal combustion engine (2) is notified, or the operation is stopped.

Description

technical field [0001] The invention relates to an exhaust purification device of an internal combustion engine. More specifically, it relates to a technique for preventing melting loss of an exhaust purification device of an internal combustion engine. Background technique [0002] Conventionally, as a technique for recovering particulates contained in exhaust gas exhausted from an internal combustion engine, an exhaust purification device for an internal combustion engine equipped with a particulate filter in the middle of an exhaust passage is known. The particulate filter has a porous honeycomb structure made of ceramics or the like, and discharges downstream only the exhaust gas that has passed through the porous walls that define the respective flow paths. A technique for removing fine particles accumulated inside the porous wall by combustion when the exhaust gas passes through the porous wall is known. However, when the exhaust gas flow rate is reduced by reducing ...

AI Technical Summary

Problems solved by technology

[0004] However, even if the exhaust gas flow rate is controlled as described above, it is difficult to completely prevent the particulate filter from melting.

In addition, when the internal combustion engine continues to operate in a state where the particulate filter is melted, there is a disadvantage that harmful substances such as particulates contained in the exhaust gas are not collected and discharged into the atmosphere.

Images