Misfire detection method based on fluctuation in crankshaft rotation
US5452604A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 2, 1994 |
| Grant date | Sep 26, 1995 |
| Priority date | — |
| Expiry date | Feb 2, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01M15/11
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A misfire detection method based on fluctuation in crankshaft rotation, in which a time interval required for the crankshaft to rotate over an angle region associated with a cylinder checked for misfire is detected in response to pulses supplied from a crank angle sensor having vanes. Next, a deviation of the crankshaft angular acceleration D .omega..sub.n, calculated based on the thus detected time interval and corresponding to the cylinder checked for misfire, from the angular acceleration D .omega..sub.n-3, corresponding to a cylinder belonging to the cylinder group to which the cylinder checked for misfire belongs, is compared with a determination value, and an occurrence/absence of misfire is detected in accordance with a result of the comparison. By using the deviation between the angular acceleration values calculated based on the time intervals detected through the use of the same vane, the bad effect of structural errors of the vanes is canceled, to thereby prevent erroneous misfire detection caused by the vane errors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.