| 摘要 |
PURPOSE:To aim at stabilizing an idling run and smoothing the run of an engine when a load is increased quickly by providing a communication passage, on the lower course of the stream from both the control valves of primary and secondary passages, to communicate said two passages together and by providing the primary control valve with an opening is opened when said primary control valve is fully closed. CONSTITUTION:At a low load run such as idling, a secondary throttle valve 38 is in the completely closed position and a primary throttle valve 36 is in the idling position, on account of which the mixture is allowed to flow through the primary passage 40 only. Primary and secondary control valves 46 (48) are in the completely closed position. The mixture flowing through the primary passage 40 is throttled at a notch 50 in the primary control valve 46 to intensify its status of swirl. At an intermediate load run, the primary throttle valve 36 is opened to weaken up negative pressure in the primary passage 40, then the primary and secondary control valves 46 (48) are opened the seconary side negative pressure is going to be intensified in association with increase of engine revolution speed, since the secondary throttle valve 38 is completely closed, however, it is prevented from being more intensified due to presence of a communication passage 52. |
