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:
Jan. 02, 2001
Filed:
Jul. 16, 1999
Luca Poggio, Spinetta Marengo, IT;
Marco Violani, Florence, IT;
Marco Secco, Nizza Monferrato, IT;
Giovanni Gaviani, Rimini, IT;
Magneti Marelli S.p.A., Milan, IT;
Abstract
A device for controlling the air/fuel ratio of the mixture supplied to an endothermal engine, in which a first and a second oxygen sensor disposed along an exhaust duct of the engine upstream and, respectively, downstream of a catalytic converter generate a first and respectively a second signal representative of the stoichiometric compositions of the combusted gases, the device having a first control circuit receiving as input the first signal and generating a correction parameter adapted to be applied to a quantity of fuel calculated in an open loop in order to obtain a corrected quantity of fuel for an injection unit of the engine, the device having a second control circuit which receives the second signal, supplies a correction signal to the first circuit in order to modify the correction parameter and has a control branch adapted to sample the second signal at a predetermined time frequency and to vary the correction signal when the difference between two successively sampled values is greater than a predetermined threshold so as to modify the air/fuel ratio and to minimise the time in which the catalytic converter operates at low efficiency.