| 摘要 |
PURPOSE:To prevent racing of a blade and to ensure its thrust, by providing a hole penetrating through the bottom surface of an annular recessed part, provided in the end part of a propeller housing, while fitting a propeller hub outer cylinder end part providing a play to the annular recessed part and discharging exhaust gas to the front of the blade from the hole in the bottom surface in the time of reversing. CONSTITUTION:A hole 21 is provided in the bottom surface of an annular recessed part 20, formed by annular ribs 18, 19, in the end part of a propeller shaft housing 15, and the hole 21 is opened to the outer of a cylindrical part 12 of a gear case 11. And the end part of a hub outer cylinder 24, equipped with propeller blades 23, of a propeller hub 22 is movably fitted to the annular recessed part 20 of the housing 15. Accordingly, in the time of reversing, the pressure of water, which acts on an exhaust port 27 with an inflow of water, causes exhaust gas to be introduced from the front of an exhaust passage 26 to the annular recessed part 20 of the housing 15 and discharged from the hole 21 along the cylindrical part 12 of the gear case 11 to the front of an outboard engine, and the propeller blade is prevented from decreasing its thrust by avoiding the exhaust gas from rolling into the propeller blade. |
