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:
Sep. 23, 1997
Filed:
Mar. 22, 1996
Kenichi Machida, Isesaki, JP;
Klaus Ries-Muller, Bad Rappenau, DE;
Unisia Jecs Corporation, Atsugi, JP;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
Apparatus and method for recognizing an absence or presence of a misfire in each of cylinders of a multi-cylinder internal combustion engine without influences of a mechanical deviation in a crank angle sensor and of a combustion state deviation between each of the cylinders. A period of each reference signal (REF) is generated from the crank angle sensor and a fuel combustion state deviation between each of the cylinders. The period of each reference signal (REF), which is generated from the crank angle sensor whenever an engine crankshaft has rotated through a predetermined crank angle expressed as 720.degree./n (n denotes a number of engine cylinders), is measured by a timer. A determination of the absence or presence of the misfire in each cylinder is made based on the measured period of the reference signal for each corresponding one of the cylinders. The measured period being corrected with either or both of first and second correction coefficients (KT.sub.i KKT.sub.i) derived by learning the corresponding first correction coefficient for the mechanical deviation and by learning the corresponding second correction coefficient for the combustion state deviation.