| 摘要 |
An outboard apparatus for propelling marine vessels includes a horizontal driving shaft, a rotated planetary gear-box and four propelling blades disposed over the surface of the water. During the rotation of the driving shaft, the blades extend into the water when their orientations are changed from horizontal to vertical positions. A propulsive force is developed as a result of a double rotation of the blades with the same speed around intercrossed axes of the driving shaft and radial shafts of the gear-box. During each propulsion stroke, circumferential velocities of the blades are gradually accelerated when they move downward. Both sides of the blades are used consecutively as working surfaces. Disposed with variable angles of incidence, the propelling blades work simultaneously as paddles and as blades of a screw propeller. The propulsion apparatus can also be used in typical outboard engines instead of the traditional screw propellers. Two vertical driving shafts with gear-boxes and propelling blades are mounted in the extension case of the outboard engine and rotated in opposite directions for developing a unidirectional propulsive force.
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