Method and apparatus for adapting a propeller and shaft system

Abstract

Method and apparatus for adapting a propeller system including a propeller shaft ( 15, 16 ) and a propeller ( 7, 8 ) adapted to be mounted on the propeller shaft ( 15, 16 ). The propeller system includes a propeller ( 7, 8 ) connected in a rotationally fixed manner to a propeller shaft ( 15, 16 ), the propeller shaft ( 15, 16 ) having a portion provided with splines ( 19, 20 ) which cooperate with corresponding splines ( 25, 28 ) inside the hub ( 23, 26 ) of the propeller ( 7, 8 ) in order to obtain the rotationally fixed connection, where the splines ( 19, 20 ) on the propeller shaft ( 15, 16 ) and in the hub ( 23, 26 ) of the propeller ( 7, 8 ) are helical, with a predetermined oblique angle (alpha, beta). The invention also relates to a propeller shaft ( 15, 16 ) and a propeller ( 7, 8 ) which are intended to be used in the propeller system.

1 . A propeller shaft arrangement adapted to be connected to an output shaft ( 11 ) of a drive motor ( 2 ) for causing propulsion of a carrying vehicle in a travel direction, the propeller shaft arrangement comprising: 
 a propeller shaft ( 15 ) having at least a portion thereof provided with a spline ( 19 ) adapted to achieve a rotationally fixed connection with a corresponding spline located inside a hub of a corresponding propeller; and    said spline ( 19 ) being oriented at an oblique angle (alpha) with respect to a longitudinal axis of said propeller shaft ( 15 ).    
     
     
         2 . The propeller shaft arrangement as recited in  claim 1 , wherein said spline ( 19 ) is helically arranged on said propeller shaft ( 15 ).  
     
     
         3 . The propeller shaft arrangement as recited in  claim 1 , wherein said spline ( 19 ) is one of a plurality of splines ( 19 ), each of said plurality of splines ( 19 ) being oriented at the predetermined oblique angle (alpha) with respect to a longitudinal axis of said propeller shaft ( 15 ).  
     
     
         4 . The propeller shaft arrangement as recited in  claim 1 , wherein said propeller shaft ( 15 ) is one of a plurality of propeller shafts ( 15 ,  16 ) having a common longitudinal axis, and each of said plurality of propeller shafts ( 15 ,  16 ) having at least one spline ( 19 ,  20 ) positioned thereupon and oriented at an oblique angle (alpha, beta) with respect to the longitudinal axis.  
     
     
         5 . The propeller shaft arrangement as recited in  claim 4 , wherein each of said at least one spline ( 19 ,  20 ) is helically arranged on the respective propeller shaft ( 15 ,  16 ).  
     
     
         6 . The propeller shaft arrangement as recited in  claim 5 , wherein each of said at least one helically arranged spline ( 19 ,  20 ) is turned in a same direction, as viewed from the rear with respect to a direction of travel of a carrying vehicle, an associated propeller would rotate to propel said propeller shaft arrangement in the direction of travel.  
     
     
         7 . The propeller shaft arrangement as recited in  claim 5 , wherein said at least one spline ( 19 ,  20 ) on each of said propeller shafts ( 15 ,  16 ) is oriented at a different oblique angle (alpha, beta) with respect to the longitudinal axis of said propeller shafts ( 15 ,  16 ).  
     
     
         8 . The propeller shaft arrangement as recited in  claim 7 , wherein each of said oblique angles (alpha, beta), with respect to the longitudinal axis of said propeller shafts ( 15 ,  16 ), is oriented such that a resultant force (F S ) between a tangential force component (F T ) of drive-motor-induced torque and a corresponding driving compressive force (F R ) is oriented at a substantially right angle to the respective receiving spline ( 19 ,  20 ) of said resultant force (F S ) when drive-motor power is applied.  
     
     
         9 . The propeller shaft arrangement as recited in  claim 7 , wherein orientations of said oblique angles (alpha, beta), as measured with respect to the longitudinal axis of said propeller shafts ( 15 ,  16 ), are predetermined based on an expected cruising speed of a drive motor to be associated therewith on a carrying vehicle.  
     
     
         10 . A propeller arrangement having a hub ( 23 ) with a through-opening ( 24 ) and blades connected thereto, the propeller arrangement being adapted to be connected, via a propeller shaft ( 15 ) to an output shaft ( 11 ) of a drive motor ( 2 ) for causing propulsion of a carrying vehicle in a travel direction, the propeller arrangement comprising: 
 a propeller ( 7 ) having at least a portion thereof provided with a spline ( 25 ) adapted to achieve a rotationally fixed connection with a corresponding spline located on a corresponding propeller shaft; and    said spline ( 25 ) being oriented at an oblique angle (alpha) with respect to a longitudinal axis of said propeller ( 7 ).    
     
     
         11 . The propeller arrangement as recited in  claim 10 , wherein said spline ( 25 ) is helically arranged on said propeller ( 7 ).  
     
     
         12 . The propeller arrangement as recited in  claim 10 , wherein said spline ( 25 ) is one of a plurality of splines ( 25 ), each of said plurality of splines ( 25 ) being oriented at the predetermined oblique angle (alpha) with respect to a longitudinal axis of said propeller ( 7 ).  
     
     
         13 . The propeller arrangement as recited in  claim 10 , wherein said propeller ( 7 ) is one of a plurality of propellers ( 7 ,  8 ) having a common longitudinal axis, and each of said plurality of propellers ( 7 ,  8 ) having at least one spline ( 25 ,  28 ) positioned thereupon and oriented at an oblique angle (alpha, beta) with respect to the longitudinal axis.  
     
     
         14 . The propeller arrangement as recited in  claim 13 , wherein each of said at least one spline ( 25 ,  28 ) is helically arranged on the respective propeller ( 7 ,  8 ).  
     
     
         15 . The propeller arrangement as recited in  claim 14 , wherein said at least one spline ( 25 ,  28 ) on each of said propellers ( 7 ,  8 ) is oriented at a different oblique angle (alpha, beta) with respect to the longitudinal axis of said propellers ( 7 ,  8 ).  
     
     
         16 . The propeller arrangement as recited in  claim 15 , wherein each of said oblique angles (alpha, beta), with respect to the longitudinal axis of said propellers ( 7 ,  8 ), is oriented such that a resultant force (F S ) between a tangential force component (F T ) of drive-motor-induced torque and a corresponding driving compressive force (F R ) is oriented at a substantially right angle to the respective receiving spline ( 25 ,  28 ) of said resultant force (F S ) when drive-motor power is applied.  
     
     
         17 . The propeller arrangement as recited in  claim 15 , wherein orientations of said oblique angles (alpha, beta), as measured with respect to the longitudinal axis of said propellers ( 7 ,  8 ), are predetermined based on an expected cruising speed of a drive motor to be associated therewith on a carrying vehicle.  
     
     
         18 . An adaptive arrangement having a through-opening ( 34 ) in a hub ( 33 ) thereof and the adaptive arrangement being configured to be interstitially positioned between a propeller ( 7 ) and a propeller shaft ( 15 ) which is coupled to an output shaft ( 11 ) of a drive motor ( 2 ) for causing propulsion of a carrying vehicle in a travel direction, the adaptive arrangement comprising: 
 an adapter ( 30 ) having a through-opening ( 34 ) with at least a portion thereof provided with a spline ( 35 ), said spline ( 35 ) adapted to achieve a rotationally fixed connection with a corresponding spline located on a corresponding propeller shaft, and said spline ( 35 ) being oriented at an oblique angle (alpha) with respect to a longitudinal axis of said adapter ( 30 ); and    an exterior of said adapter ( 30 ) being configured for rotationally fixed engagement with a corresponding propeller.    
     
     
         19 . The adaptive arrangement as recited in  claim 18 , wherein said spline ( 35 ) is helically arranged on said adapter ( 30 ).  
     
     
         20 . The adaptive arrangement as recited in  claim 18 , wherein said spline ( 35 ) is one of a plurality of splines ( 35 ), each of said plurality of splines ( 35 ) being oriented at the predetermined oblique angle (alpha) with respect to a longitudinal axis of said adapter ( 30 ).  
     
     
         21 . The adaptive arrangement as recited in  claim 18 , wherein said adapter ( 30 ) is one of a plurality of adapters ( 30 ,  31 ) having a common longitudinal axis, and each of said plurality of adapters ( 30 ,  31 ) having at least one spline ( 35 ,  38 ) positioned thereupon and oriented at an oblique angle (alpha, beta) with respect to the longitudinal axis.  
     
     
         22 . The adaptive arrangement as recited in  claim 21 , wherein each of said at least one spline ( 35 ,  38 ) is helically arranged on the respective adapter ( 30 ,  31 ).  
     
     
         23 . The adaptive arrangement as recited in  claim 22 , wherein said at least one spline ( 35 ,  38 ) on each of said adapters ( 30 ,  31 ) is oriented at a different oblique angle (alpha, beta) with respect to the longitudinal axis of said adapters ( 30 ,  31 ).  
     
     
         24 . The adaptive arrangement as recited in  claim 23 , wherein each of said oblique angles (alpha, beta), with respect to the longitudinal axis of said adapters ( 30 ,  31 ), is oriented such that a resultant force (F S ) between a tangential force component (F T ) of drive-motor-induced torque and a corresponding driving compressive force (F R ) is oriented at a substantially right angle to the respective receiving spline ( 35 ,  38 ) of said resultant force (F S ) when drive-motor power is applied.  
     
     
         25 . The adaptive arrangement as recited in  claim 23 , wherein orientations of said oblique angles (alpha, beta), as measured with respect to the longitudinal axis of said adapters ( 30 ,  31 ), are predetermined based on an expected cruising speed of a drive motor to be associated therewith on a carrying vehicle.  
     
     
         26 . A propulsion arrangement adapted to be connected to an output shaft ( 11 ) of a drive motor ( 2 ) for causing propulsion on a carrying vehicle in a travel direction, the propulsion arrangement comprising: 
 a propeller ( 7 ) having at least a portion thereof provided with a spline ( 25 ) adapted to achieve a rotationally fixed connection with a corresponding spline ( 19 ) located on a corresponding propeller shaft ( 15 ), said spline ( 25 ) on said propeller ( 7 ) being oriented at an oblique angle (alpha) with respect to a longitudinal axis of said propeller ( 7 ); and    said propeller shaft ( 15 ) having at least a portion thereof provided with said spline ( 19 ) adapted to achieve a rotationally fixed connection with the corresponding spline ( 25 ) located inside the propeller ( 7 ), said spline ( 19 ) of said propeller shaft ( 15 ) being oriented at an oblique angle (alpha) with respect to a longitudinal axis of said propeller shaft ( 15 ).    
     
     
         27 . The propulsion arrangement as recited in  claim 26 , wherein said splines ( 19 ,  25 ) are helically arranged on said propeller shaft ( 15 ) and said propeller ( 7 ), respectively.  
     
     
         28 . The propulsion arrangement as recited in  claim 26 , further comprising: 
 said propeller ( 7 ) being one of a plurality of propellers ( 7 ,  8 ) having a common longitudinal axis, and each of said plurality of propellers ( 7 ,  8 ) having at least one spline ( 25 ,  28 ) positioned thereupon and oriented at an oblique angle (alpha, beta) with respect to the longitudinal axis;    said propeller shaft ( 15 ) being one of a plurality of propeller shafts ( 15 ,  16 ) having a common longitudinal axis, and each of said plurality of propeller shafts ( 15 ,  16 ) having at least one spline ( 19 ,  20 ) positioned thereupon and oriented at an oblique angle (alpha, beta) with respect to the longitudinal axis; and    said splines ( 19 ,  20 ,  25 ,  28 ) being configured for mating engagement that fixes relative rotational movement between said propeller ( 7 ) and said propeller shaft ( 15 ) when drive-motor power is applied.