Air-fuel ratio control device for internal combustion engine

Abstract

Abstract PURPOSE:To improve learning precision and to improve transient response, by a method wherein a learning value during steady running is computed by means of a target air-fuel ratio, an actual air-fuel ratio, and a feedback correction amount, which serve as a parameter, and a learning value during transient running is computed by a fundamental injection amount and a transient correction amount, which serve as a parameter. CONSTITUTION:Detecting values from a throttle valve opening sensor 25, a crank angle sensor 32, a water temperature 33, an oxygen sensor 34 and the like are inputted to a control unit 35, and from the opening of a throttle valve and the number of revolutions, an intake air amount is determined to compute a fundamental injection amount. Feedback control is made on the fundamental fuel injection amount based on a detecting value from the oxygen sensor 34, and during deceleration, feedback control is applied thereon by means of a transient correction amount responding to a fuel delay due to a change in an amount of fuel adhered. Further, a learning correction factor during steady running is renewed is renewed by means of a target air-fuel ratio, an actual air-fuel ratio, and a feedback correction factor, which serve as a parameter, and a learning correction factor during a transient state is renewed by means of the target-air-fuel ratio factor, the actual air-fuel ratio, and the feedback correct ion factor, which serve as a fundamental fuel injection pulse width and a transient correction amount.

Inventors

• 👤 Hatsuo Nagaishi
• 👤 初雄 永石
• 👤 Hiromichi Miwa
• 👤 博通 三輪
• 👤 Kazuhiro Sanbu
• 👤 三分　一寛
• 👤 Masaaki Uchida
• 👤 正明 内田

Bibliographic Details