Patent ID: 11959407
Assignee: ISUZU MOTORS LIMITED
Field: Chemical engineering (Chemistry)
Classification: CPC F  B  Y | IPC B  F

Claim 4:
5. A detection method for detecting collapse of particulate matter collected in a filter provided in an exhaust system flow path of an internal combustion engine, the detection method comprising:
acquiring a differential pressure between an exhaust inlet side and an exhaust outlet side of the filter and determining whether water is generated in the exhaust system flow path;
determining that at least a part of the particulate matter collected in the filter has collapsed when the acquired differential pressure has increased by a predetermined differential pressure or more within a predetermined period or a particulate matter accumulation amount in the filter estimated based on the acquired differential pressure has increased by a predetermined accumulation amount or more within the predetermined period, in a state where:
the acquired differential pressure is equal to or larger than a predetermined first differential pressure threshold or the particulate matter accumulation amount in the filter estimated based on the differential pressure is equal to or larger than a predetermined first accumulation amount threshold; and
the determining determines that water is generated in the exhaust system flow path; and

acquiring a water temperature of cooling water of the internal combustion engine,
wherein the determining includes determining that water is generated in the exhaust system flow path in a case where a water temperature decrease amount during a stop period which is obtained by subtracting a restart-time water temperature from a stop-time water temperature is equal to or larger than a predetermined amount, the restart-time water temperature being acquired in the acquiring of the water temperature when the internal combustion engine is restarted, and the stop-time water temperature being acquired in the acquiring of the water temperature when the internal combustion engine is stopped.