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. 14, 1999
Filed:
Aug. 08, 1997
Susumu Shinohara, Toyota, JP;
Tomohiro Fujita, Toyota, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota, JP;
Abstract
An apparatus for detecting misfires in an internal combustion engine that is mounted on a vehicle. A plurality of cylinders is defined in the engine, and a piston accommodated in each cylinder to reciprocate in the cylinder. A crankshaft is connected with the piston, the crankshaft is rotated by the reciprocal movement of the piston. An engine speed sensor is provided for detecting the rotating speed of the crankshaft. An electronic control unit (ECU) computes the deviation of rotating speed of the crankshaft corresponding to each cylinder based on the detected engine speed, and the deviation is proportional to the engine load. The ECU costs a leaning value based on the computed deviation, wherein the learning value is used for detecting the misfires in the engine. A memory is provided for storing the learning value. Several sensors are provided for detecting a running condition of the engine, wherein the condition is included the engine load. The ECU renews the learning value stored in the memory based on the detected condition of the engine. The ECU determines whether the misfires occurs in each cylinder based on the difference between the deviation and the learning value. The ECU renews the learning value when the engine load is less than a predetermined value.