Patent ID: 8473183

Claim:
A control device for an internal combustion engine, comprising: target torque setup means for setting a target torque; target air-fuel ratio setup means for setting a target air-fuel ratio and periodically varying the target air-fuel ratio; air amount control torque setup means for setting an air amount control torque in accordance with the target torque; target air amount calculation means for calculating a target air amount, which is an air amount required in order to achieve the air amount control torque at a predetermined virtual air-fuel ratio, in accordance with predetermined data that associates an air-fuel ratio with an air amount versus torque relationship prevailing at an optimum ignition timing; air amount control means for controlling an air amount in accordance with the target air amount; estimated air amount calculation means for calculating an air amount that is estimated to be achieved by the air amount control; estimated torque calculation means for calculating an estimated torque in accordance with the predetermined data that associates the air-fuel ratio with the air amount versus torque relationship prevailing at the optimum ignition timing, the estimated torque being estimated to be achieved by the estimated air amount at the target air-fuel ratio; ignition timing control means for providing ignition timing control by correcting ignition timing so as to compensate for the difference between the estimated torque and the target torque; and fuel injection amount control means for controlling a fuel injection amount in accordance with the target air-fuel ratio.