Method of detecting abnormality in crank angle signal of internal combustion engines
US4788956A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 23, 1986 |
| Grant date | Dec 6, 1988 |
| Priority date | — |
| Expiry date | May 23, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01M15/06
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A method of detecting an abnormality in a crank angle signal of an internal combustion engine having a crankshaft. The method comprises the steps of monitoring the condition of a first reference position signal generated at a predetermined crank angle position of the crankshaft and the condition of a second position signal generated whenever the crankshaft rotates through a predetermined rotational angle, setting a first flag to a predetermined logical state if the first reference position signal is generated before the second position signal is generated a predetermined number of times after generation of the first reference position signal, setting a second flag to a predetermined logical state if the first reference position signal is not generated after the second position signal has been generated said predetermined number of times after generation of the first reference position signal and before an immediately succeeding generation of the second position signal; and detecting an abnormality in one of the first reference position signal and second position signal based on a predetermined combination of logical states exhibited by the first and second flags.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.