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:
Oct. 14, 1997
Filed:
Sep. 25, 1996
Kojiro Tsutsumi, Wako, JP;
Shuichi Hosoi, Wako, JP;
Shigeto Kashiwabara, Wako, JP;
Katsuhiko Suzuki, Wako, JP;
Sachito Fujimoto, Wako, JP;
Honda Giken Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
An air-fuel ratio control system for an internal combustion engine has an exhaust gas component concentration sensor having a sensor element and arranged in the exhaust system of the engine, for detecting concentration of a predetermined component present in exhaust gases emitted from the engine. An ECU controls the air-fuel ratio of an air-fuel mixture supplied to the engine, based on results of comparison between an output value from the sensor and a predetermined reference value, and detects deterioration of the exhaust gas component concentration sensor, based on the output value from the sensor. Engine operating condition sensors detect operating conditions of the engine. It is determined whether or not the engine is in a predetermined engine operating condition in which the sensor element temperature of the exhaust gas component concentration sensor lowers, based on outputs from the engine operating condition sensors. Detection of deterioration of the sensor is inhibited over a predetermined time period after the engine leaves the predetermined operating condition.