Patent · US Expired

Apparatus and method for detecting misfires in internal combustion engine

US5951617A · kind A · utility

14Cited by
9References
40Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 8, 1997
Grant dateSep 14, 1999
Priority date
Expiry dateAug 8, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01M15/11
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

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 EC…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.