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. 21, 2002
Filed:
Apr. 17, 2000
Honda Giken Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A system for discriminating degradation of an exhaust purification system of an internal combustion engine having an adsorbent installed at a bypass exhaust gas passage branched from an exhaust pipe of the engine, which is opened by a switch-over valve at starting of the engine to introduce the exhaust gas such that the adsorbent adsorbs unburned HC in exhaust gas generated by the engine and is closed such that the adsorbent desorbs the adsorbed HC and the desorbed HC is thereafter recirculated at a position upstream of a catalyst. Based on the fact that the HC concentration rising time interval becomes short as the adsorbent degrades and adsorption capacity decrease, the time lapse since engine starting until the detected HC concentration exceeds a predetermined level is measured and is compared with a threshold value such that the adsorbent is discriminated to be degraded if the measured time lapse is less than the threshold value, thereby enabling to improve the discrimination accurately.