Adjustment Device For Adjusting Propeller Blades of a Propeller Pump and a Propeller Pump Including Such a Device

Abstract

The present invention relates to an adjustment device for adjusting the pitch angle of the propeller blades ( 4 ) of a propeller pump ( 1 ) and a propeller pump incorporating such a device. The adjustment device comprises adjustment means ( 5; 25; 35 ) mounted within the hub ( 2 ) arranged to be axially movable in a direction along the drive shaft ( 7 ), the adjustment means ( 5; 25; 35 ) being provided with a plurality of guide slots ( 6; 26 a , 26 b ; 36 ) arranged at circumferential spacings around the surface; a plurality of attachment means ( 20 ) rotationally mounted in the hub ( 2 ), each being fixedly attached to a propeller blade ( 4 ) and supported by at least one guide slot ( 6; 26 a , 26 b ; 36 ), wherein each attachment means ( 20 ) and the corresponding at least one guide slot ( 6; 26 a , 26 b ; 36 ) are arranged to interact such that a force applied on the attachment means ( 20 ) is distributed symmetrically about an axis perpendicular to the drive shaft ( 7 ) and parallel with a rotational axis of the attachment means ( 20 ); and wherein the guide slots ( 6; 26 a , 26 b ; 36 ) are arranged to, at an axial movement of the adjustment means ( 5; 25; 35 ), cause the attachment means ( 5; 25; 35 ) to rotate about its own rotational axis, whereby the propeller blade ( 4 ) in turn is rotated.

1 . Propeller pump ( 1 ) comprising a hub ( 2 ), bearings incorporated therein, a plurality of propeller blades ( 4 ) mounted in said bearings and projecting from said hub ( 2 ), comprising an adjustment device for adjusting the pitch angle of said propeller blades ( 4 ) about an axis perpendicular to a drive shaft ( 7 ) of the propeller ( 1 ), wherein comprises
 adjustment means ( 5 ;  25 ;  35 ) mounted within said hub ( 2 ) arranged to be axially movable in a direction along the drive shaft ( 7 ), said adjustment means ( 5 ;  25 ;  35 ) being provided with a plurality of guide slots ( 6 ;  26   a ,  26   b ;  36 ) arranged at circumferential spacings around an envelope ( 8 ;  28   a - 28   d ;  38 ) of the adjustment means ( 5 ;  25 ;  35 ], characterized in that the device further comprises;   a plurality of attachment means ( 20 ) rotationally mounted in said   
     hub ( 2 ), each being fixedly attached to a propeller blade ( 4 ) and comprises at least two guide means [ 22 ], each slidably supported by a guide slot ( 6 ;  26   a ,  26   b ;  36 ), wherein each guide means [ 22 ] and said corresponding guide slot ( 6 ;  26   a ,  26   b ;  36 ) are arranged to interact such that a force applied on said attachment means ( 20 ) is distributed symmetrically about an axis perpendicular to the drive shaft ( 7 ) and parallel with a rotational axis of said attachment means ( 20 ); and
 wherein said guide slots ( 6 ;  26   a ,  26   b ;  36 ) are arranged to, at an 
 
     axial movement of said adjustment means ( 5 ;  25 ;  35 ), cause said attachment means ( 20 ) to rotate about their own rotational axis, whereby the corresponding propeller blades ( 4 ) in turn are rotated. 
   
   
       2 . Propeller pump according to  claim 1 , wherein each attachment means ( 20 ) is supported by two inclined guide slots ( 6 ). 
   
   
       3 . Propeller pump according to  claim 2 , wherein said two inclined guide slots ( 6 ) consist of one upper guide slot, in a direction along said drive shaft ( 7 ), and one lower guide slot, in a direction along said drive shaft ( 7 ), said upper and said lower guide slot being symmetrically arranged about a centre, in a direction along the drive shaft ( 7 ), perimeter line of said adjustment means ( 5 ) such that an angle is formed between each guide slot ( 6 ) and said perimeter line. 
   
   
       4 . Propeller pump according to  claim 1 , wherein each attachment means ( 20 ) is supported by one guide slot ( 36 ) provided with a V-shape and being symmetrically arranged about a centre, in a direction along the drive shaft ( 7 ), perimeter line of said adjustment means ( 35 ). 
   
   
       5 . Propeller pump according to  claim 1 , wherein said adjustment means ( 5 ;  35 ) is a cylinder concentric with said drive shaft ( 7 ), said guide slots ( 6 ;  36 ) being arranged on the outer envelope surface ( 8 ;  38 ) of said cylinder. 
   
   
       6 . Propeller pump according to  claim 1 , wherein said attachment means ( 20 ) comprises:
 an attachment plate ( 20 ) upon which said propeller blade ( 4 ) is mounted; and   at least two guide pins ( 22 ) slidably supported by said at least one guide slot ( 6 ;  36 ) and fixedly mounted on said attachment plate ( 20 ),   wherein said at least two pins ( 22 ) at an axial movement of said adjustment means ( 5 ;  35 ) are arranged to slide in said at least one guide slot ( 6 ;  36 ), thereby causing said rotation of said attachment means ( 20 ) about its own rotational axis.   
   
   
       7 . Propeller pump according to  claim 6 , wherein two pins ( 22 ) are fixedly mounted on said attachment plate ( 20 ) at diametrically opposed locations in a direction along said drive shaft ( 7 ), a first pin being slidably supported by said upper guide slot and a second pin being supported by said lower guide slot. 
   
   
       8 . Propeller pump according to  claim 1 , wherein said adjustment means ( 5 ;  25 ;  35 ) is connected to adjusting screw means, said adjusting screw means being arranged to move said adjustment means ( 5 ;  25 ;  35 ) axially. 
   
   
       9 . Propeller pump according to  claim 1 , wherein said axial movement of said adjustment means ( 5 ;  25 ;  35 ) is controlled by an electrical motor ( 17 ). 
   
   
       10 . Adjustment device for a propeller pump ( 1 ) comprising a hub ( 2 ), bearings incorporated therein, a plurality of propeller blades ( 4 ) mounted in said bearings and projecting from said hub ( 2 ), for adjusting the pitch angle of said propeller blades ( 4 ) about an axis perpendicular to a drive shaft ( 7 ) of the propeller ( 1 ) in accordance with  claim 1 .