| 摘要 |
PURPOSE:To facilitate the production of a suction port by connecting the lengthwise lower space of a branch path branched from a inlet passage section to the inlet passage section in the cross section. CONSTITUTION:A suction port 6 is composed of a volute section B formed around a suction valve 5 and an inlet passage section A. A branch path 19 is provided on the inlet passage section A, and the lengthwise lower space of the branch path 19 is connected to the inlet passage section A in the cross section along its whole length. Accordingly, a core can be formed from a halved split wooden pattern and the suction port 6 can be produced very easily. In addition, by providing a slant side wall face 13 on the inlet passage section A, a strong eddy current can be generated during a low speed and low load operation of the engine, and the high charging efficiency can be assured during a high speed and high load operation of the engine because of the action suppressing the eddy current. |
