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:
Feb. 03, 1987
Filed:
Apr. 30, 1985
Katsuhiko Kodama, Oobu, JP;
Hisamitsu Yamazoe, Kariya, JP;
Nippondenso Co., Ltd., Kariya, JP;
Abstract
In engine control apparatus with exhaust gas recirculation control and air/fuel ratio feedback control, the amount of recirculated exhausted gasses is accurately detected so as to operate an internal combustion engine under an optimal operating condition all the time. To this end a correction factor derived from oxygen sensor output, which is used for air/fuel ratio control, is monitored to obtain a difference of a correction factor value resulted from engine operation with EGR and another correction factor value resulted from engine operation with EGR. This difference is obtained by forcibly interrupting EGR operation. Once the amount of recirculated exhaust is accurately estimated, the EGR control and/or air/fuel ratio control are performed with compensation for possible error due to secular change in EGR system.