System and method for detecting engine cylinder misfire
US6243641A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 19, 1998 |
| Grant date | Jun 5, 2001 |
| Priority date | — |
| Expiry date | Oct 19, 2018 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02D2200/1015
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A system and method in which the exhaust manifold pressure is measured by a single gauge-type pressure sensor positioned in the exhaust manifold to detect misfires in all cylinders of an internal combustion engine. The pressure sensor detects the exhaust manifold pressure and feeds a signal to a microcomputer via an analog-to-digital converter. A data processing device monitors the pressure waveform created by the data from the sensor to determine if a full or partial misfire occurs. If a cylinder suffers from a partial or complete misfire, the strength of the pressure pulse for that cylinder will be reduced, thus, allowing the data processing device to identify the misfire. The data processing device may determine a misfire by computing an average peak pressure for each combustion cycle, a pressure threshold as a function of engine speed and fuel consumption rate, and a minimum pressure value based on the difference between the average peak pressure and the pressure threshold. The data processing device may alternatively determine a misfire by first computing a coefficient of variation between an observed pressure pulse and the average peak pressure and then comparing the coeffici…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.