Ignition system tester
US4449100A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 5, 1982 |
| Grant date | May 15, 1984 |
| Priority date | — |
| Expiry date | Apr 5, 2002 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02P17/00
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
This specification discloses testing vehicle primary ignition systems by taking the integral of the primary spark plug firing voltage versus time over a time period when the spark should occur. To determine when an integration output should be evaluated, a phase locked loop circuit is used to predict the occurrence of an ignition firing pulse. To compensate for changes in engine speed and yet disregard extraneous spark plug firings, the phase locked loop circuit contains two loop filters having different response times which are automatically selected to minimize response to erroneous or missing spark plug firings and maximize response to actual engine RPM changes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.