Folding Propeller for a Water Vehicle

Abstract

The present disclosure relates to a folding propeller (10) for a water vehicle, comprising a hub (12) which is drivable about a rotation axis (D) via a drive shaft, and a propeller blade (14) which is arranged on the hub (12) to be pivotable about a pivot axis (S) between a maximum closed position (P1) and a maximum open position (P2), wherein the pivot axis (S) defines, together with a normal (ND) to the rotation axis (D) which intersects the pivot axis (S), a maximum opening plane (EMax), wherein in the driven state and a pivot position of the propeller blade (14) in the region of the maximum open position (P2), at least one opening force acts upon the propeller blade (14) which results from rotation of the folding propeller (10) and in relation to the rotation axis (D) is directed substantially radially outwardly, wherein an effective force application point (EAP) of the opening force is arranged spaced from the maximum opening plane (EMax) and is substantially arranged in the closing direction (SR) of the propeller blade (14). The present disclosure further relates to a folding propeller (10) comprising a propeller blade (14) which has a reversal element (143) which is configured such that during rearward drive a reversed thrust (Freverse) acts upon the reversal element (143) and is directed substantially perpendicularly to the propeller blade longitudinal axis (LP) in the opening direction (OR) of the propeller blade (14).

1 . A folding propeller for a water vehicle, the folding propeller comprising:
 a hub drivable about a rotation axis via a drive shaft, and a propeller blade arranged on the hub to be pivotable about a pivot axis between a maximum closed position and a maximum open position,   wherein the pivot axis defines, together with a normal to the rotation axis which intersects the pivot axis, a maximum opening plane,   wherein in a driven state and a pivot position of the propeller blade in a region of the maximum open position, an opening force acts upon the propeller blade which results from rotation of the folding propeller and in relation to the rotation axis is directed substantially radially outwardly,   wherein an effective force application point of the opening force is arranged spaced from the maximum opening plane and is substantially arranged in a closing direction of the propeller blade.   
     
     
         2 . The folding propeller according to  claim 1 , wherein the effective force application point of the opening force corresponds to a center of mass of the propeller blade,
 wherein one or both of the opening force is a centrifugal force or the effective force application point of the opening force corresponds to the center of pressure of an uplift body arranged on the propeller blade,   wherein the opening force is an uplift force.   
     
     
         3 . The folding propeller according to  claim 1 ,
 wherein the folding propeller has a stop apparatus which defines the maximum open position of the propeller blade and the effective force application point of the opening force is arranged outside the maximum opening plane in the closing direction such that in the maximum open position of the propeller blade, an opening moment acts which presses the propeller blade against the stop apparatus.   
     
     
         4 . The folding propeller according to  claim 1 ,
 wherein the propeller blade has an additional body that is one or both of configured as an uplift body or configured as a mass body,   wherein the uplift body is configured as a winglet and the mass body has a curved cylinder.   
     
     
         5 . The folding propeller according to  claim 1 ,
 wherein the propeller blade has a first propeller blade portion that is distally arranged, and a second propeller blade portion that is proximally arranged,   wherein the first propeller blade portion is offset relative to the second propeller blade portion substantially in the closing direction.   
     
     
         6 . The folding propeller according to  claim 1 ,
 wherein the propeller blade has a propeller blade tip portion, a propeller blade shaft portion and a propeller blade root portion,   wherein the propeller blade shaft portion is arranged between the propeller blade tip portion and the propeller blade root portion, and   wherein one or both of the propeller blade shaft portion or the propeller blade tip portion is offset relative to the propeller blade root portion substantially in the closing direction of the propeller blade.   
     
     
         7 . The folding propeller according to  claim 6 ,
 wherein the propeller blade is configured such that a center of mass of the propeller blade is arranged distally in relation to a centroid of the propeller blade, wherein the center of mass of the propeller blade is arranged either in the propeller blade tip portion or in the propeller blade shaft portion.   
     
     
         8 . The folding propeller according to  claim 1 ,
 wherein the propeller blade has a propeller root, wherein the propeller root has a mounting apparatus for attaching the propeller blade to the hub and the mounting apparatus defines the pivot axis.   
     
     
         9 . The folding propeller according to  claim 6 ,
 wherein the propeller blade has an additional body that is configured as one or more of an uplift body or as a mass body,   wherein one or both of the propeller blade tip portion or the additional body is formed of metal.   
     
     
         10 . The folding propeller according to  claim 9 , wherein the propeller blade or the propeller blade tip portion is configured integrally with the additional body. 
     
     
         11 . The folding propeller according to  claim 6 , wherein one or both of the propeller blade shaft portion or the hub is formed at least partially of plastics. 
     
     
         12 . The folding propeller according to  claim 6 , wherein the propeller blade tip portion is one or both of connected form-fittingly or frictionally to the propeller blade shaft portion. 
     
     
         13 . The folding propeller according to  claim 6 , wherein the propeller blade tip portion has a tongue which is one or both of cast into the propeller blade shaft portion or is connected to the propeller blade shaft portion via a releasable connection, in particular a screw connection. 
     
     
         14 . The folding propeller according to  claim 1 , wherein a metal insert is embedded in the propeller blade. 
     
     
         15 . A folding propeller for a water vehicle, the folding propeller comprising:
 a hub drivable about a rotation axis via a drive shaft, and a propeller blade arranged on the hub to be pivotable about a pivot axis,   wherein the propeller blade has a reversal element, which is configured such that during rearward drive, a reversed force acts upon the reversal element and is directed substantially perpendicularly to a propeller blade longitudinal axis in an opening direction of the propeller blade.   
     
     
         16 . The folding propeller according to  claim 15 , wherein the reversal element is arranged in a propeller blade tip portion. 
     
     
         17 . The folding propeller according to  claim 15 , wherein the reversal element is arranged on the propeller blade to be pivotable about the pivot axis which is substantially parallel to the propeller blade longitudinal axis. 
     
     
         18 . The folding propeller according to  claim 15 , wherein the reversal element is pivotable between a maximum folded-in position and a maximum folded-out position,
 wherein the reversal element assumes a maximum folded-in position when the folding propeller is in forward drive,   wherein in the maximum folded-in position, the reversal element is oriented substantially aligned with the propeller blade,   wherein the reversal element assumes the maximum folded-out position when the folding propeller is in rearward drive,   wherein in the maximum folded-out position, the reversal element experiences the reversed force.   
     
     
         19 . The folding propeller according to  claim 15 , wherein the reversed force generates an opening moment on the propeller blade via a lever to the pivot axis. 
     
     
         20 . A drive for a water vehicle having a folding propeller comprising:
 a hub which is drivable about a rotation axis via a drive shaft, and a propeller blade which is arranged on the hub to be pivotable about a pivot axis between a maximum closed position and a maximum open position,   wherein the pivot axis defines, together with a normal to the rotation axis which intersects the pivot axis, a maximum opening plane,   wherein in a driven state and a pivot position of the propeller blade in a region of the maximum open position, an opening force acts upon the propeller blade which results from rotation of the folding propeller and in relation to the rotation axis is directed substantially radially outwardly,   wherein an effective force application point of the opening force is arranged spaced from the maximum opening plane and is substantially arranged in a closing direction of the propeller blade.   
     
     
         21 . A drive for a water vehicle having a folding propeller comprising:
 a hub drivable about a rotation axis via a drive shaft, and   a propeller blade arranged on the hub to be pivotable about a pivot axis,   wherein the propeller blade has a reversal element, which is configured such that during rearward drive, a reversed force-acts upon the reversal element and is directed substantially perpendicularly to a propeller blade longitudinal axis in an opening direction of the propeller blade.