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:
Jun. 05, 2001
Filed:
Oct. 19, 1998
Eric B. Andrews, Columbus, IN (US);
Axel O. zur Loye, Columbus, IN (US);
Mark R. Stepper, Columbus, IN (US);
Cummins Engine Company, Inc., Columbus, IN (US);
Abstract
A system and method in which the exhaust manifold pressure is measured by a single gauge-type pressure sensor positioned in the exhaust manifold to detect misfires in all cylinders of an internal combustion engine. The pressure sensor detects the exhaust manifold pressure and feeds a signal to a microcomputer via an analog-to-digital converter. A data processing device monitors the pressure waveform created by the data from the sensor to determine if a full or partial misfire occurs. If a cylinder suffers from a partial or complete misfire, the strength of the pressure pulse for that cylinder will be reduced, thus, allowing the data processing device to identify the misfire. The data processing device may determine a misfire by computing an average peak pressure for each combustion cycle, a pressure threshold as a function of engine speed and fuel consumption rate, and a minimum pressure value based on the difference between the average peak pressure and the pressure threshold. The data processing device may alternatively determine a misfire by first computing a coefficient of variation between an observed pressure pulse and the average peak pressure and then comparing the coefficient of variation with a pressure threshold to determine if at least a partial misfire has occurred.