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. 03, 2004
Filed:
Aug. 05, 2003
Honda Giken Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
After an internal combustion engine has started to operate, a changing timing is detected at which a humidity represented by the output signal of a humidity sensor disposed downstream of a hydrocarbon adsorbent changes to a tendency to monotonously increase from a low humidity to a high humidity. Data representing a total amount of moisture carried by an exhaust gas emitted by the internal combustion engine to the hydrocarbon adsorbent up to the changing timing is acquired as a deterioration evaluating parameter. The deteriorated state of the hydrocarbon adsorbent is evaluated based on the deterioration evaluating parameter. The changing timing is detected as a timing at which the relative humidity represented by the output signal of the humidity sensor has changed from a low humidity to a high humidity by a preset value. The preset value is variably set in order to compensate for characteristic changes of the humidity sensor and variations of individual humidity sensors. The deteriorated state of the hydrocarbon adsorbent can thus adequately be monitored while compensating for the characteristic changes of the humidity sensor and the variations of individual humidity sensors.