Monitoring apparatus for fuel feed system
US6422226B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 15, 2001 |
| Grant date | Jul 23, 2002 |
| Priority date | — |
| Expiry date | Feb 15, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A highly stable engine failure diagnosing system free from influence of purging is presented. A monitoring apparatus for monitoring a fuel feed system of an internal combustion engine is provided with an A/F ratio detector and an A/F ratio controller for performing feedback control of the A/F ratio. An A/F ratio feedback coefficient is calculated according to the output of the detector. A malfunction determination parameter is calculated based on the coefficient. A purging is suspended when the parameter reaches a first decision value. The monitoring is suspended when the parameter reaches a second decision value in a purge cutting state. A value of the malfunction determination parameter it would take if the purge cut was not carried out is estimated using the value when the parameter reached the first decision value. The monitoring is resumed when the estimated value of the malfunction determination parameter reaches the second decision value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.