Misfire-detecting system for internal combustion engines
US5327867A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 3, 1993 |
| Grant date | Jul 12, 1994 |
| Priority date | — |
| Expiry date | Mar 3, 2013 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02P2017/125
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A misfire-detecting system for an internal combustion engine carries out self-diagnosis of the system. In the system, sparking voltage generated across a spark plug of a cylinder of the engine is detected, and the detected sparking voltage is compared with a first predetermined reference voltage value, and a time period is measured over which the detected sparking voltage exceeds the first predetermined reference voltage value. It is determined that a misfire occurred in the engine when the measured time period exceeds a predetermined time period value. It is determined whether the engine is in self-sustaining operation. When it is determined that the engine is in self-sustaining operation, it is determined whether the misfire-detecting system is abnormal. It is determined that the misfire-detecting system is abnormal when the detected sparking voltage is lower than a second reference voltage value. Alternatively or in combination, it is determined that the misfire-detecting system is abnormal when the detected sparking voltage has continued to be higher than a third predetermined reference voltage value over a predetermined time period.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.