Failure diagnosis device for an engine which compares airfuel ratio and exhaust pressure with a predetermined value
US5287283A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 3, 1991 |
| Grant date | Feb 15, 1994 |
| Priority date | — |
| Expiry date | Apr 3, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01M15/104
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A failure diagnosis device for determining engine abnormalities by comparing the air-fuel ratio or the exhaust pressure of an engine with a predetermined value or by determining that the air fuel ratio or the exhaust pressure of the engine is different from the average air-fuel ratio or the average exhaust pressure by a predetermined amount. This comparison is made only when the engine is in a predetermined running condition in which either the air-fuel ratio or the exhaust pressure is stabilized for a predetermined period of time. When the air-fuel ratio or exhaust pressure is different from the average air-fuel ratio or from the average exhaust pressure by a predetermined value, engine abnormality can be detected for each cylinder or for each cylinder group.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.