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:
Sep. 24, 1996
Filed:
Sep. 08, 1994
Akihito Numata, Ibaraki, JP;
Takashi Mukaihira, Katsuta, JP;
Toshio Ishii, Mito, JP;
Yutaka Takaku, Katsuta, JP;
Kazuya Kawano, Katsuta, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
Provided is an internal combustion engine malfunction diagnosis apparatus capable of diagnosing the deterioration of an internal combustion engine with a high accuracy and capable of diagnosing deterioration of a fluctuation factor detection section of the engine with a high accuracy in irrespective of the engine speed. According to one embodiment of the present invention, there is provided a malfunction diagnosis apparatus for an internal combustion engine comprises: a crank angle detection sensor for detecting a crank angle of the internal combustion engine; a fluctuation factor measurement means for measuring a state of a fluctuation factor of the internal combustion engine; an angular-based data sampling section for sampling data of an output signal from the fluctuation factor measurement means at a predetermined rotation angle of a crank shaft in accordance with a crank angle signal from the crank angle detection sensor; a malfunction judgement section for judging a malfunction of the internal combustion engine on the basis of data sampled by the angular-based data sampling section; a time-based data sampling section for sampling an output signal from the fluctuation factor measurement means at every lapse of a predetermined constant time; and a fluctuation factor measurement means deterioration judgement section for judging deterioration of the fluctuation factor measurement means on the basis of data sampled by the time-based data sampling section.