| 摘要 |
PURPOSE:To improve fuel atomization over the whole driving range, by installing a suction passage projectingly over a range from a throttle valve to nearly the central part of a volumetric enlargement chamber where branch parts of a suction manifold are concentrated and opening the passage, while forming a choke at a terminal part of the opening. CONSTITUTION:A suction manifold 1 for four cylinders in a single suction system has each of symmetrical suction passages 1a and 1b, while both these passages 1a and 1b are concentrated at a volumetric enlargement chamber 1c. A throttle body 4 carrying a throttle valve 5 is interconnected to this volumetric enlargement chamber 1c via an insulator 6. At the same time, an umbrella part 3 partitioning a suction passage 1d ranging from the side of the throttle body 4 to nearly the central part of the chamber 1c is projectingly installed in the chamber 1c. And, at the tip end side of this umbrella part 3, a tapered choke 2 is installed, and its tip end 3a is formed into a sharp edge. A choking quantity of this choke is set down to, for example, about 30% of the passage area of a throttle bore D whereby an output drop in time of being fully opened is prevented. |
