INTERNAL COMBUSTION ENGINE EQUIPPED WITH MECHANICAL SUPERCHARGER AND SUPERCHARGING METHOD THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide an internal combustion engine equipped with a mechanical supercharger capable of generating supercharging pressure close to a target supercharging pressure of a steady state and performing an exhaust gas improvement, even in a transition state of operation of an internal combustion engine, and in addition, capable of reducing driving losses of a mechanical supercharger and suppressing deterioration of fuel consumption, and to provide a supercharging method therefor.SOLUTION: In internal combustion engines 1, 1A equipped with a turbocharger 7 and a mechanical supercharger 6, in a transition state and when a supercharging pressure of the turbocharger 7 cannot be increased, the supercharging pressure is boosted using the mechanical supercharger 6, the supercharging pressure by the mechanical supercharger 6 is lowered in synchronization with boosting of the supercharging pressure by the turbocharger 7, and at the time point when the supercharging pressure of the turbocharger 7 becomes a required target supercharging pressure Pc, the mechanical supercharger 6 is stopped and supercharging control for switching to the turbocharger 7 is performed.