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. 01, 1997
Filed:
Jul. 25, 1995
Naoyuki Ozaki, Hitachinaka, JP;
Matsuo Amano, Hitachi, JP;
Hiroshi Ohnishi, Hitachinaka, JP;
Toshimichi Minowa, Mito, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An engine power train control method and control apparatus for a vehicle having an engine and an automatic transmission is capable of quickly changing an air-fuel ratio to meet the requirements for exhaust gas without producing shocks and without reducing engine torque. An air-fuel ratio command value is varied stepwise for transition between an air-fuel ratio for lean-burn operation and a stoichiometric air-fuel ratio, and at the same time, the period following the completion of the stepwise variation of the air-fuel ratio command value, a basic fuel amount fed to the engine is varied stepwise from a value determined according to the air amount and an engine speed to a value determined according to a position of an accelerator pedal of the vehicle and the engine speed. In this way, shocks do not occur and the operability is improved, because the engine torque remains substantially constant through the air-fuel ratio transition.