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:
Mar. 07, 1995
Filed:
Sep. 29, 1992
Toshio Ishii, Mito, JP;
Takashi Mukaihira, Katsuta, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An apparatus for combustion condition diagnosis has an ionic current detecting circuit for measuring a voltage at the secondary side of the ignition coil of an engine during a plurality of time periods during one operation cycle including a period in which an internal pressure of a cylinder of the engine becomes maximum, under a normal combustion condition. A window generation circuit is provided for establishing the time periods, an integration circuit is provided for integration processing of the measured voltage during each time period, a ROM stores a list indicating combustion condition corresponding to the integrated value for the each time period, and a CPU diagnoses the combustion condition based on the integrated value for the each time period and the list of combustion conditions, in order to decrease erroneous judgement and perform more adequate combustion condition diagnosis.