摘要 |
A first and second turbochargers (16A, 16B) for supercharging a first cylinder group which continues or stops an operation by a valve stopping mechanism (21) for reduced cylinders and a second cylinder group which stops or continues the operation by the valve stopping mechanism (21) for reduced cylinders, respectively, are provided, and a third turbocharger (26) in which an air A from these both turbochargers (16A, 16B) is supplied to the first and second cylinder groups via separate independent intake passages (12A, 12B), and supercharging the both turbochargers (16A, 16B) is provided. As a result, if a reduced-cylinder operation system provided with the valve stopping mechanism configured to temporarily stop intake/exhaust valves are provided in addition to the turbo-charging system, a drop in a supercharging amount during a reduced-cylinder operation is prevented, a sufficient air amount is supplied into operating cylinders, deterioration of combustion in the operating cylinders and deterioration of a state of an exhaust gas which can easily occur during the reduced-cylinder operation are prevented, and an effect of fuel efficiency improvement is sufficiently obtained. |