Patent ID: 7693646

Claim:
A control device of an internal combustion engine having an injector that supplies fuel into a combustion chamber and a valve-actuating mechanism capable of changing an opening characteristic of at least one of an intake valve and an exhaust valve, and that generates power by burning a mixture of fuel and air in the combustion chamber, comprising: an intake pressure detection device that detects intake air pressure upstream of the combustion chamber; an in-cylinder pressure detection device that detects in-cylinder pressure in the combustion chamber; a controller that estimates an anticipated amount of air that will be aspired into the combustion chamber in response to a demand for the internal combustion engine; calculates an amount of air aspired into the combustion chamber based on a first in-cylinder pressure detected by the in-cylinder pressure detection device at a first timing that occurs during a compression stroke and before combustion starts in the combustion chamber, an intake air pressure detected by the intake pressure detection device at a second timing that occurs during a period of time when opening periods of the intake and exhaust valves overlap, and a pressure of exhaust gas during the period of time when opening periods of the intake and exhaust valves overlap, wherein the controller estimates the pressure of the exhaust gas during the period of time when opening periods of the intake and exhaust valves overlap based on a second in-cylinder pressure detected by the in-cylinder pressure detection device at a third timing that occurs before or at a start of the period of time when opening periods of the intake and exhaust valves overlap; and causes the injector to inject an initial amount of fuel determined so that a first air-fuel ratio of a first mixture in the combustion chamber is higher than a target value in accordance with the anticipated amount of air estimated by the controller, and causes the injector to inject a correction amount of fuel determined based on the initial amount of fuel and the amount of air aspired into the combustion chamber calculated by the controller so that a second air-fuel ratio of a second mixture in the combustion chamber corresponds to the target value.