Air-fuel ratio control device

Abstract

Abstract PURPOSE:To prevent the amount of fuel from being excessively compensated due to apparent variations in intake-air pipe pressure in association with variations in atmospheric pressure, by compensating the amount of fuel during control of exhaust gas recirculation in accordance with a differential pressure between the intake-air pipe pressure and the atmospheric pressure, and the rotational speed of an engine. CONSTITUTION:There is provided an operating condition detecting means II comprising a rotational speed detecting part IIA for detecting the rotational speed of an internal combustion engine I and an intake-air pipe pressure detecting part IIB for detecting the pressure of an intake-air pipe, and a differential pressure detecting means IV for detecting a differential pressure between the intake-air pressure and the atmospheric pressure. Further, there is provided a recirculation control means V for controlling a recirculation passage opening and closing means III disposed in an exhaust gas recirculation passage, for recirculating a part of exhaust gas into the intake-air pipe in accordance with output signals from the detecting means II, V. Further, there is provided a fuel injection amount determining means VI for calculating the basic amount of fuel injection in accordance with the result of detection of the engine rotational speed and the pressure of the intake-air pipe and for compensating the basic amount of fuel injection in accordance with the result of detection of the rotational speed and the above-mentioned differential pressure when the above-mentioned opening and closing means is opened.

Inventors

• 👤 Katsushi Kato
• 👤 克司 加藤
• 👤 Katsuhiko Kigami
• 👤 樹神　勝彦

Bibliographic Details