Method and device for measuring fuel injection timing
US5767396A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 10, 1997 |
| Grant date | Jun 16, 1998 |
| Priority date | — |
| Expiry date | Mar 10, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
An injection timing measuring method and device require a reduced amount of time for calculation. A reference position signal is generated at a predetermined crank angle within the range of 30.degree. CA to 90.degree. CA prior to TDC. Crank angle signals from a crank angle sensor are used as main measuring increments to measure a period starting from generation of the reference position signal and ending upon generation of an injection signal by a lift sensor provided in an injection valve unit, and another period starting from generation of the reference position signal and ending upon generation of a TDC signal. The injection timing relative to the TDC is provided as a difference between the two periods. Each period is precisely measured by counting crank angle signals generated within the period and by determining the remaining duration from the last-counted signal to generation of the injection or TDC signal as a fraction of the crank angle signal interval. Measurement of the injection period starts from an injection start time at which the level of the injection signal exceeds a criterion value, and ends upon an injection end time at which the level falls below the criterion v…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.