| 摘要 |
The present invention concerns a propelling unit for propelling a vessel through water, said propelling unit comprising: a rotor comprising a plurality, preferably two or more, foldable hydrodynamic blades, said rotor being mounted on a drive shaft connected to drive means for propelling said vessel by rotating said rotor around an axis, a shielding shield shiftable between a first and second position, wherein the shielding shield in said first position is adapted to cover and to accommodate the rotor with the blades in their retracted position, and wherein the shielding shield in the second position allows for the blades to be extracted, wherein an extraction mechanism is provided for performing said shifting between the first and second positions. |
