| 摘要 |
PURPOSE:To smooth the connection of the supercharge pressure control when an exhaust cut valve is opened in the high flow quantity area of an engine to operate the second supercharger by flowing a part of the exhaust gas with an exhaust leaking means to give the prerotation. CONSTITUTION:When an operated condition detecting means detects that an engine reaches the high flow quantity area, a switching control means opens an exhaust cut valve to operate the second turbosupercharger. At this stage, a part of the exhaust gas is flowed by an exhaust leaking means, and the prerotation is given to the second supercharger before the exhaust cut valve is opened, and the exhaust cut valve is opened at the time that the rotation is raised. On the other hand, in the low flow quantity area where only the first supercharger operates and the second supercharger does not operate, the exhaust leaking means works as a supercharge pressure control valve, and the operation of a waist gate valve is restrained by a restraining means, and the restraint is cancelled in the second supercharger operating area so that the supercharge pressure control is performed by the waist gate valve. Thereby, the connection of the supercharge pressure control is smoothed, and the fluctuation of the maximum supercharge pressure can be prevented. |
