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. 14, 1984
Filed:
Dec. 21, 1981
Takuro Morozumi, Mitaka, JP;
Mitsuo Nakamura, Tokyo, JP;
Masaaki Ohgami, Musashino, JP;
Ryuji Kataoka, Tokyo, JP;
Fuji Jukogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
An air-fuel ratio control system for an internal combustion engine comprises an induction passage, a carburetor, an on-off type electromagnetic valve for correcting the air-fuel ratio of the air-fuel mixture supplied to the carburetor, an O.sub.2 -sensor for detecting oxygen concentration of exhaust gases, and a feedback control circuit responsive to the output of the O.sub.2 -sensor for producing pulses for driving said electromagnetic valve for correcting the air-fuel ratio. An engine speed detecting circuit is provided for producing an output signal which varies with the engine speed; and a frequency changing circuit is provided to be responsive to the output signal of the engine speed detecting for changing the frequency of the pulses whereby the electromagnetic valve may be prevented from resonating with the vibration of the engine and with the pulsations of induced air.