| 摘要 |
The present invention relates to a propeller with retractable blades arranged on a hub, said hub being limitedly rotatable in relation to the propeller drive shaft, each of said blades being pivotable between an outward working position and an inward inactive position, whereby power and movement transmission means determining the pivoting position of the blades unites the drive shaft and the blades and is arranged at least when the propeller rotates in one of its both directions of rotation to compulsorily open out the blades by mutual turning movement between the drive shaft and hub. The propeller is particularly, but not exclusively, intended for competition sailing boats to give the least amount of resistance when the boat is under sail and the propeller retracted. Previous constructions have not functioned completely reliably in practice, especially not when reversing. |
