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. 31, 1993
Filed:
Jul. 10, 1992
Masanobu Uchinami, Hyogo, JP;
Mitsubishi Denki K.K., Tokyo, JP;
Abstract
This invention relates to a trouble diagnosis device for an exhaust gas recirculation (EGR) of an internal combustion engine. In the condition that an EGR control valve is turned on and off according to whether or not the operating condition of the engine is in the EGR control zone, and a trouble diagnosis condition is satisfied, sensors detect a plurality of engine operation conditions. A trouble diagnosis device receives the output detected by one of the sensors and compares the output with a predetermined value of the same kind as the output a normal state of the EGR system corresponding to the engine condition detected by the sensors, thereby the trouble of the EGR control system is diagnosed. Specifically, one of the sensors detects NO.sub.x in exhaust gas or exhaust gas temperature.