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:
Dec. 30, 1997
Filed:
Nov. 01, 1996
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A misfire detecting apparatus for an internal combustion engine which can ensure enhanced reliability for detection of the misfire event by suppressing the so-called after-burning ion current generated in an engine cylinder controlled in precedence and superposed on a normal or regular ion current generated in a cylinder controlled in succession. The apparatus includes a bias voltage supplying means (9a, 9b) for applying a bias voltage (VBi) to the spark plugs (8a to 8d) by way of the high-voltage diodes (11a to 11d), an ion current detecting means for detecting ion currents (i) flowing through the spark plugs and an electronic control unit (2) for driving the ignition coil (4) and determining misfire event in the internal combustion engine on the basis of the ion current detection signal (Gia, Gib). The ion current detecting means includes a plurality of ion current detecting circuits for detecting ion currents in the engine cylinders belonging to a plurality of cylinder groups. The engine cylinders belonging to each cylinder group are so selected as not to be controlled in succession for ignition. In making misfire decision, the electronic control unit (2) makes use of the ion current detection signal derived from the ion current detection circuit means provided in association with the cylinder group which includes the engine cylinder currently subjected to the ignition control.