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:
Aug. 22, 2000
Filed:
Jan. 16, 1997
Yutaka Takaku, Mito, JP;
Toshio Ishii, Mito, JP;
Kazuya Kawano, Hitachinaka, JP;
Nobuo Kurihara, Hitachiota, JP;
Hiroshi Kimura, Hitachinaka, JP;
Kiyoshi Miura, Ibaraki-ken, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
There is disclosed a leakage diagnosis of an evaporative system in an internal combustion engine, and more particularly there is disclosed an evaporative system in which a more accurate leakage diagnosis can be effected using a change in the pressure in the evaporative system, and such a diagnosis method is also disclosed. The evaporative system includes a gauge line having a gauge valve, which gauge line branches off from an evaporative gas line or an evaporative gas purge line, and communicates with a point upstream of an engine throttle valve or with the ambient atmosphere, a pressure sensor for detecting the pressure in the evaporative system, and a purge valve. A leakage diagnosis of this system is effected based on detected values of the pressure sensor obtained by opening and closing the purge valve and the gauge valve. Therefore, accurate results of the diagnosis can be obtained.