| 摘要 |
PURPOSE:To enable to supply proper air-fuel mixture over the entire region of engine operation, by opening auxiliary fuel passages communicating a primary and a secondary main fuel passages with bottom portions of float chambers by a first solenoid valve at the time of supercharged operation and opening said auxiliary fuel passages by a second solenoid valve when a secondary throttle valve is fully opened. CONSTITUTION:In non-supercharged state, proper air-fuel mixture is supplied by closing an auxiliary jet 17 by a valve body 20 of a first solenoid valve 19. On the other hand, at the time of partial-load operation of an engine when the engine is supercharged in the state that only a primary throttle valve 4 is opened slightly or a secondary throttle valve 6 is also opened slightly, the auxiliary jet 17 is opened by the valve body 20 of the first solenoid valve 19 to supply appropriately corrected air-fuel mixture according to the operational conditions of the engine. Further, at the time of supercharged operation of the engine when the secondary throttle valve 6 is also fully opened, a valve body 28 of a second solenod valve 27 is opened through operation of a switch 29, and most of correction fuel is passed to a secondary main fuel passage 12 via an auxiliary fuel passage 16b and a seat 26, whereby it is enabled to supply appropriately corrected air-fuel mixture. |
