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. 29, 1995
Filed:
Jun. 24, 1993
Koichi Namiki, Kyoto, JP;
Takuya Matsumoto, Kyoto, JP;
Toru Hashimoto, Kyoto, JP;
Yasuhisa Yoshida, Okazaki, JP;
Mitsubishi Jidosha Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A method and apparatus of detecting faults for a fuel evaporative emission treatment system, in which the fuel evaporative emission which is admitted from a fuel tank and absorbed once by a canister is separated from the canister by purge air and sucked in a suction pipe of an engine. Under the control of an electronic control unit, a vent port of the canister is closed by closing a vent solenoid valve, and a purge control valve installed in a pipe connecting an outlet port of the canister to the suction pipe is opened. Thereby, a negative pressure of suction air is applied to the fuel tank via another pipe connecting the above-mentioned pipe and the inlet port of canister to the fuel tank to reduce the internal pressure of the fuel tank. Then, the reduction of the internal pressure of the fuel tank is completed by closing the control valve. Afterward, the pressure rise generated in the fuel tank from the time when the exhaust is completed is detected on the basis of the output of a pressure sensor. If the degree of pressure rise is high, it is judged that the fuel evaporative emission system has a fault such as poor airtightness.