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:
Oct. 13, 1998
Filed:
Nov. 18, 1992
Seiji Asano, Katsuta, JP;
Toshio Ishii, Mito, JP;
Masayoshi Kaneyasu, Farmington Hills, MI (US);
Kazuya Kawano, Katsuta, JP;
Takashi Mukaihira, Katsuta, JP;
Hitachi, Ltd., , JP;
Abstract
A conversion efficiency of a catalyst is determined by a cross correlation function of a cross-correlation between an output of an oxygen sensor at the upstream of the catalyst and an output of an oxygen sensor at the downstream of the catalyst, to thereby monitor deterioration index of the catalyst. Then, an air and fuel ratio is obtained from at least one of the outputs of the two oxygen sensors, to thereby adjust a fuel supply quantity, so that the fuel supply quantity can be controlled even during a period when the catalyst is being analyzed, without deviating the air and fuel ratio from a target air and fuel ratio.