FIELD: internal combustion engines.
SUBSTANCE: invention relates to a control device and a control method for an internal combustion engine provided with a variable compression ratio mechanism. Internal combustion engine has a variable compression ratio mechanism using a multi-link piston crank mechanism, by moving the top dead centre position of the piston up or down and is equipped with a fuel injection valve which injects fuel into the cylinders. During a high load the fuel injection period increases, but with the present invention the target compression ratio becomes a low compression ratio during a high load, and the fuel injection start timing is before the exhaust top dead centre, so the fuel injection period straddles the exhaust top dead centre. When the compression ratio is low (characteristic 'b') the distance between the fuel injection valve and the crown surface of the piston near the top dead centre increases as indicated by the symbol 'H', so even if the injection occurs near the top dead centre smoke is not easily generated, and the injection period can be lengthened to straddle the top dead centre.
EFFECT: technical result is longer fuel injection time at high load.
5 cl, 3 dwg
