Engine misfire detection with compensation for normal acceleration of crankshaft
US5574217A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 6, 1995 |
| Grant date | Nov 12, 1996 |
| Priority date | — |
| Expiry date | Jun 6, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01M15/11
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus and method are provided for detecting cylinder misfires in an internal combustion engine of a motor vehicle which is capable of detecting multiple cylinder misfires and more particularly opposed cylinder misfires. Crankshaft rotation is sensed and crankshaft velocities are measured for each cylinder. Changes in angular velocity are determined and correspond to each of a plurality of cylinder firing events. Angular velocity changes are sorted over a predetermined series of cylinder firings and the two middle most angular velocity changes are averaged to provide an average change in velocity value. A deviation is determined between the change in angular velocity for a selected cylinder and the average change in velocity value. The deviation is compared to a threshold value and a misfire event is determined for the selected cylinder based on the comparison.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.