| 摘要 |
<p>A water jet propulsion machine for a marine vessel, having a suction port (4) at a ship's bottom in the vicinity of a stern, the water sucked from this suction port (4) into a suction duct (5) being pressurized by a spiral vane (10) provided in an impeller housing (6), jet water being then ejected from an ejection duct (13) to the rear side of the stern. A vane wheel shaft (7) provided in the impeller housing (6) is mounted thereon with a plurality of phase-staggered spiral vanes (10), and the outer circumferential edge portions (10b) of these spiral vanes (10) are extended close to an inner circumferential surface of the impeller housing (6), the outer circumferential ends (10c) of the spiral vanes (10) being extended toward the suction side, a current straightening guide vane (12) being provided in the portion of a flow passage which is behind the spiral vanes (10). The rolling of a ship body and cavitation occurring when a ship travels at a high speed are minimized, and the travelling performance of a ship is thereby improved.</p> |
