Patent ID: 8789500

Claim:
A spark ignition type internal combustion engine comprising: a variable compression ratio mechanism which can change a mechanical compression ratio; a variable valve timing mechanism which can control a closing timing of an intake valve; and an electronic control unit that includes control logic, which when executed: determines when a demanded intake air amount changes, determines an operating point for the mechanical compression ratio and the closing timing of the intake valve that satisfies the changed demanded intake air amount, and repeatedly determines successive target operating points that can be reached after successive fixed times in order to move the mechanical compression ratio and the closing timing of the intake valve without entering a non-entry region for a combination of the mechanical compression ratio and the closing timing of the intake valve, wherein the successive target operating points are between a current operating point for the mechanical compression ratio and the closing timing of the intake valve and the operating point that satisfies the changed demanded intake air amount, and wherein the successive target operating points are repeatedly determined until the mechanical compression ratio and the closing timing of the intake value reach the operating point that satisfies the changed demanded intake air amount.