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. 04, 2002
Filed:
Aug. 29, 2000
Katsuhiko Toyoda, Shizuoka-ken, JP;
Suzuki Motor Corporation, , JP;
Abstract
A purge control system of an engine has a purge valve which is opened and closed in accordance with the state of operation of the engine so as to establish a purge-on mode and a purge-off mode, thereby controlling purge rate which is the flow rate of the purge gas supplied to said engine. An air-fuel ratio feedback controller performs feedback control of the air-fuel ratio based on an output signal from an air-fuel ratio sensor and a purge density which is computed as the concentration of the evaporated fuel in the purge gas supplied to said engine. An air-fuel ratio correcting device performs, in the purge-on mode, a purge learning control having a plurality of cycles for learning the results of computations of the purge density and for effecting correction of the air-fuel ratio based on purge learned values obtained through the learning. The air-fuel ratio correcting device effects, in the purge-off mode, correction of the air-fuel ratio based on normal learned values learned in the purge-off mode. The system further has a control unit for setting the number of the purge learning cycles and the number of the normal learning cycles, so as to vary the frequency of the purge learning cycles, based on the state of the computed purge density.