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:
Apr. 24, 2001
Filed:
May. 28, 1999
Takeshi Shimizu, Tokyo, JP;
Koichi Okamura, Tokyo, JP;
Mituru Koiwa, Tokyo, JP;
Yutaka Ohashi, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
There is provided a combustion state detecting device for an internal combustion engine even in the case where disconnection of a secondary current path or misfire in an ignition plug occurs. A voltage developed at the secondary winding low voltage side is suppressed so that the high voltage can be prevented from being leaked. The combustion state detecting device for an internal combustion engine includes a capacitor,for charging a positive bias voltage necessary for detecting ions generated when an ignition plug,discharges upon application of the ignition high voltage, a resistor,disposed between the low voltage side of the secondary winding and the capacitor for suppressing the drop of the bias voltage, ion current detecting means,for detecting a discharge current from the capacitor as an ion current flowing through the ignition plug, an ECU,for detecting a combustion state in the ignition plug on the basis of a detection value of the ion current detecting means, and a Zener diode,for suppressing a voltage developed when a path in which the ion current flows is disconnected.