| 摘要 |
PURPOSE:To exactly detect the quantity of intake at the beginning of supercharging by a super charger installed in an auxiliary intake passage, by providing a passage for connecting the part of the auxiliary intake passage between an intake flow rate detector and an auxiliary throttle valve to an intake passage downstream to a main throttle valve or the auxiliary throttle valve and by providing a control valve, which opens the connecting passage at the beginning of supercharging. CONSTITUTION:In a low-load operation in which the degree of opening of a main throttle valve 5 is lower than a prescribed level, an auxiliary throttle valve 10 in an auxiliary intake passage 3 is closed and a connecting passage 17 is closed by a control valve 19. When the degree of opening of the main throttle valve 5 has exceeded the prescribed level, the auxiliary throttle valve 10 begins to open to start supercharging, and the control valve 19 also opens. As a result, even at the beginning of the supercharging at which the intake flow rate through the auxiliary throttle valve 10 is smaller than the detectable flow rate minimum of an air flow meter 11 in the auxiliary intake passage 3 because of the low degree of opening of the throttle valve 10, a flow rate larger than the detectable flow rate minimum is provided by air being aupplied to an engine body 1 through the connecting passage 17, so that the flow rate detection by the air flow meter is enabled. |
