Patent ID: 8229649

Claim:
A spark ignition type internal combustion engine provided with a variable compression ratio mechanism able to change a mechanical compression ratio and a variable valve timing mechanism able to control a closing timing of an intake valve, wherein an amount of intake air supplied to a combustion chamber is mainly controlled by changing the closing timing of the intake valve, the mechanical compression ratio is increased toward a maximum mechanical compression ratio as the amount of intake air supplied to the combustion chamber is reduced, the amount of intake air supplied to the combustion chamber is reduced as the closing timing of the intake valve is moved in a direction away from an intake bottom dead center toward a limit closing timing, and, when the closing timing of the intake valve reaches the limit closing timing, the amount of intake air supplied to the combustion chamber becomes a control limit intake air amount which is a control limit by the variable valve mechanism, and when the amount of intake air supplied to the combustion chamber is further reduced from the control limit intake air amount, the closing timing of the intake valve is held at the limit closing timing, wherein, when an acceleration operation is performed when the amount of intake air supplied to the combustion chamber is smaller than the control limit intake air amount, if the required acceleration degree is higher than a predetermined degree, the movement of the closing timing of the intake valve from the limit closing timing in a direction approaching the intake bottom dead center is started when the amount of intake air supplied to the combustion chamber is smaller compared with when the required acceleration degree is lower than the predetermined degree.