Evaporative fuel-processing system for internal combustion engines
US5678523A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 1, 1996 |
| Grant date | Oct 21, 1997 |
| Priority date | — |
| Expiry date | Mar 1, 2016 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02M25/0809
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
An evaporative fuel-processing system for an internal combustion engine has an evaporative emission control system and a pressure sensor. An ECU carries out negative pressurization of the interior of the evaporative emission control system, by opening a purge control valve and closing a vent shut valve. The purge control valve is closed over a predetermined time period after the interior of the evaporative emission control system is brought into the predetermined negatively pressurized state, and a rate of decrease in negative pressure within the evaporative emission control system is detected. Then, it is determined whether or not there is leakage from the evaporative emission control system, based on the detected rate of decrease in the negative pressure, and at least one detected pressure value at at least one predetermined time point within the predetermined time period over which the purge control valve is closed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.