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:
May. 15, 2007
Filed:
May. 22, 2006
Hisanori Ozaki, Tokyo, JP;
Akira Kiyomura, Gunma, JP;
Hisanori Ozaki, Tokyo, JP;
Akira Kiyomura, Gunma, JP;
Fuji Jukogyo Kabushiki Kaisha, Tokyo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
When carrying out abnormality determination for an air-fuel ratio sensorby comparison of an average value tave of all diagnostic values t(n) and an abnormality determination value C, the abnormality determination value C is corrected using an average value Δtave for the disturbance correction values Δt(n). A disturbance correction value Δt(n) is derived by subtracting a correction reference value A, which is a diagnostic value with a normal air-fuel ratio sensorwhen there is no disturbance, from the diagnostic value t(n). The present invention provides the abnormality diagnosis device for the air-fuel ratio sensor that can acquire highly precise diagnosis results without lowering frequency of diagnosis accurately taking into consideration the influence of disturbance.