| 摘要 |
A boat propulsion device, wherein a curved tube-shaped propeller (2) is formed, on a bottom (1b), of a front casing (12) having a suction port (11) opened under water on a bow side, an impeller casing (10) for inscribing an impeller (17) therewith, and a rear casing (14) having a delivery port (13) opened under water on a stern side so that the impeller (17) can be rotated in forward and reverse directions. |
