Evaporative fuel-processing system for internal combustion engines
US5690076A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 1, 1996 |
| Grant date | Nov 25, 1997 |
| Priority date | — |
| Expiry date | Mar 1, 2016 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02M25/08
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
An evaporative fuel-processing system for an internal combustion engine has an evaporative emission control system. 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, and determines presence/absence of leakage from the evaporative emission control system, based on a rate of decrease in negative pressure within the system, by closing a purge control valve. Before the negative pressurization, the interior of the evaporative emission control system is opened to the atmosphere, and during the open-to-atmosphere, a pressure state within the fuel tank is estimated based on a rate of change in an output from a pressure sensor which senses pressure within the evaporative emission control system. The ECU determines whether the evaporative emission control system is normal, based on the estimated pressure state.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.