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:
Nov. 09, 1999
Filed:
Jun. 01, 1998
Yue Yun Wang, Columbus, IN (US);
Edward J Lewandowski, Scipio, IN (US);
Cummins Engine Company, Inc., Columbus, IN (US);
Abstract
A system and method for detecting a misfire condition for a cylinder of an internal combustion engine is based upon the firing times for each cylinder and a comparison of firing times between successive cylinders in the engine firing sequence. A differential firing time parameter represents the result of this comparison and is used a passive test to determine whether a particular cylinder is misfiring. Cylinders identified in the passive test are subjected to an active test in which the cylinder is overfueled by increasing amounts for each engine cycle after commencement of the active misfire test. The change in differential firing parameter for the identified resulting from the overfueling is compared to an active test threshold value indicative of an expected change for a healthy cylinder. A cylinder falling outside this active threshold value is determined to be a bad cylinder.