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:
Apr. 29, 1997
Filed:
Jul. 11, 1995
Yoichi Kadota, Himeji, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A misfire detector for an internal combustion engine is provided which, if any of a plurality of modification factors is replaced by a value out of the proper range, can prevent erroneous misfire detection from, continuing. The misfire detector comprises a period measurement unit of signals generated by a crank angle sensor, a modification factor calculating unit for, based on a ratio between the periods of the plurality of signals in a steady operating condition, calculating a plurality of modification factors used to modify errors in period values, a modification factor propriety determining unit for determining whether the plurality of modification factors calculated by the modification factor calculating unit are in the proper range or not, a period variation factor calculating unit for, based on the periods values and the modification factors which have been determined as being proper, calculating each period variation factor used to quantitize variations in the period, and a misfire determining unit for determining the occurrence of a misfire based on the period variation factor calculated by the period variation factor calculating unit.