COMPRESSION RATIO ADJUSTING DEVICE FOR INTERNAL COMBUSTION ENGINE AND METHOD FOR CONTROLLING COMPRESSION RATIO ADJUSTING DEVICE FOR INTERNAL COMBUSTION ENGINE

摘要

An object of the present invention is to provide a novel compression ratio adjusting apparatus for an internal combustion engine that can improve a knocking resistance performance and also prevent or cut down an increase in a temperature of exhaust gas. The compression ratio adjusting apparatus is configured to relatively decrease a mechanical compression ratio in a high load area of the internal combustion engine and also adjust a mechanical expansion ratio at this time to a relatively high ratio. According to this configuration, the compression ratio adjusting apparatus performs control of decreasing the mechanical compression ratio in the high load area of the internal combustion engine and also increasing the mechanical expansion ratio at this time, thereby succeeding in improving the knocking resistance performance and also preventing or cutting down the increase in the temperature of the exhaust gas, thus succeeding in reducing thermal damage on a part in an exhaust system.