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:
Aug. 29, 1995
Filed:
May. 25, 1994
Yukihiro Yamashita, Kariya, JP;
Toshihiro Suzumura, Nagoya, JP;
Nippondenso Co., Ltd., Kariya, JP;
Abstract
For stable air-fuel ratio control without hunting, an output condition of an air-fuel ratio sensor is monitored to decide whether or not a modern or advanced control using a dynamic model may be performed. The appropriateness of using the dynamic model may be determined by monitoring whether the output value of an air-fuel ratio sensor exists in a predetermined range or whether the air-fuel ratio sensor is maintained stably in an air-fuel ratio detectable state. When the sensor output condition is out of the predetermined range suitable for the modern control, an optimum feedback gain for performing the modern control is switched over to a lowered gain or the modern control is switched over into normal feedback control by proportional-and-integral control. By this control mode switch-over, most appropriate air-fuel ratio feedback control may be performed.