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. 03, 1990
Filed:
Aug. 19, 1988
Teruji Sekozawa, Kawasaki, JP;
Makoto Shioya, Tokyo, JP;
Motohisa Funabashi, Sagamihara, JP;
Mikihiko Onari, Kokubunji, JP;
Masami Shida, Mito, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
The fuel injection quantity required for maintaining the air-fuel ratio of the mixture supplied to each cylinder of an engine at a desired value is determined by a deposition rate X at which injected fuel deposits and forms a film mass on an intake manifold wall of the engine and a vaporization rate 1/.tau. at which the film mass vaporizes from the manifold wall, a current film mass quantity M.sub.f determined from the calculated X and l/.tau. and the fuel quantity by the preceding injection, a desired fuel quantity Q.sub.a /(A/F) to be supplied air-fuel ratio A/F in accordance with the following equation ##EQU1## an air-fuel ratio feedback correction factor .gamma. aiming at a stoichiometric air-fuel ratio based on a signal generated by an O.sub.2 sensor is calculated and an actual quantity of fuel corresponding to G.sub.f .multidot..gamma. is injected. A film mass quantity in a current computing cycle is based on the film mass quantity calculated during the previous computing cycle.