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:
Jul. 21, 1981
Filed:
Nov. 07, 1979
Allen W Lindberg, Kirkwood, MO (US);
Thomas R Gantzert, Florissant, MO (US);
Donald L Hicks, St. Louis, MO (US);
ACF Industries, Incorporated, New York, NY (US);
Abstract
Apparatus for controlling the air-fuel ratio in an internal combustion engine to substantially maintain the ratio at a predetermined value while the engine is operating under various load conditions. The engine has a carburetor with an air passageway through which air is drawn into the engine. Fuel is supplied to the carburetor through a fuel system and mixed with air passing through the carburetor. The presence of oxygen in the combustion products, which is a function of the air-fuel ratio of the mixture, is sensed and a first electrical signal representative of the oxygen content is supplied. The first electrical signal is compared with a predetermined reference level which is a function of the predetermined value to produce a second electrical signal having first and second signal elements, a first signal element being produced when the air-fuel ratio of the mixture is greater than the predetermined level and a second signal element being produced when the ratio is less than the level. A control responsive to the second electrical signal supplies to an air metering unit a control signal by which the quantity of air introduced into the fuel system is controlled. A change in the control signal is produced whenever the second electrical signal has a transition from one signal element to the other thereby for the air metering unit to change the quantity of air introduced into the fuel system conduit by an amount necessary to substantially maintain the air-fuel ratio at the predetermined value.