| 摘要 |
PURPOSE:To improve the acceleration responsiveness of an engine which is provided with a throttle valve in the closely upper course from an air intake port and a volume chamber in the upper course form the throttle valve, by providing midway a pass for a high speed with a secondary valve that is opened in the high speed and a pass for a low speed without a valve. CONSTITUTION:The upper course from a primary throttle valve 14 provided in an air intake pass 6 located in the upper course from an air intake valve 2, is connected to a volume chamber 12 with a large volume for every cylinder. The passes between the volume chamber 12 and the primary throttle valve 14 are classified into two systems; one system comprises passes 6b for a high speed with secondary throttle valves 16, the other comprises passes 6a for a low speed without any valve. Since the secondary throttle valves 16 are closed in the low speed of an engine, the internal pressure from the upper course from the primary throttle valve 14 to the inside of the volume chamber 12 can be reduced to a value nearly equal to that of the atmospheric pressure. When the primary and secondary throttle valves 14 and 16, respectively, are opened in the acceleration of the engine, air intake ports can immediately take in a large amount of the air, whereby an acceleration responsiveness can be improved. |
