摘要 |
A spark ignition type internal combustion engine of the present invention is provided with a variable compression ratio mechanism able to change a mechanical compression ratio, a variable valve timing mechanism able to control a closing timing of an intake valve, and a supercharger. At the time of engine low load operation, the mechanical compression ratio is made higher compared with at the time of engine high load operation. At the time of engine medium load operation, the supercharging action of the supercharger is used to make the pressure inside the intake pipe rise so that the intake air amount fed into a combustion chamber is increased, compared with at the time of engine low load operation, and the mechanical compression ratio is lowered to make the actual compression ratio fall. |