The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 25, 1996
Filed:
Feb. 17, 1995
Hiroyuki Aota, Kariya, JP;
Junya Morikawa, Kasugai, JP;
Nippondenso Co., Ltd., Kariya, JP;
Abstract
An air/fuel control system for an internal combustion engine or the like delivers evaporated gas from the engine's fuel tank and adsorbed in a canister to an intake of the engine via a discharge route. A purge vacuum switching valve (VSV 16) disposed in the discharge route controls the rate at which the evaporated gas is delivered to the engine intake. Using a sensor, the air/fuel ratio of the engine intake is determined and the deviation of the detected air/fuel ratio from a target ratio calculated according to learned air/fuel ratio parameters is calculated. The density of the evaporated fuel stream is determined based on that deviation, and the VSV is driven based on the calculated evaporated gas density. If the air/fuel parameters are not learned within a predetermined time, the VSV is driven at a fixed rate. A drive signal to the engine's fuel injection system also may be corrected based on the calculated evaporated fuel density.