Paddle blade

Abstract

A paddle blade that is actuatable with respect to a paddle shaft between a deployed state and a folded state. In use, during the power stroke of a paddling action, the action of the water on the blade causes the blade to adopt the deployed state in which the blade performs in a manner similar to a conventional paddle blade. During the recovery stroke, the action of the water, or other medium, causes the blade to adopt the folded state thereby reducing the drag or resistance of the blade. Hence, the recovery stroke may be performed without removing the blade from the water.

1 . A blade for a paddle, the blade being actuatable between a deployed state and a folded state.  
   
   
       2 . A blade as claimed in  claim 1 , wherein the blade is foldable with respect to a longitudinal axis of the paddle.  
   
   
       3 . A blade as claimed in  claim 1 , wherein the blade is foldable on itself.  
   
   
       4 . A blade as claimed in  claim 1 , wherein the blade is generally planar when deployed.  
   
   
       5 . A blade as claimed in  claim 1 , the blade being connected, in use, to a shaft of the paddle and being actuatable with respect to the shaft between the deployed state, in which the blade lies generally in a first plane, and the folded state in which the blade is displaced from said first plane.  
   
   
       6 . A blade as claimed in  claim 5 , wherein the blade is pivotable with respect to the shaft about an axis that lies generally in said first plane.  
   
   
       7 . A blade as claimed in  claim 6 , wherein said axis is generally perpendicular with the longitudinal axis of the shaft.  
   
   
       8 . A blade as claimed in  claim 1 , wherein the blade, when in the deployed state, lies generally in the same plane as the longitudinal axis of the paddle.  
   
   
       9 . A blade as claimed in  claim 1 , wherein the blade comprises a frame carrying at least one flexible sheet.  
   
   
       10 . A blade as claimed in  claim 9 , wherein the frame is pivotable with respect to the shaft.  
   
   
       11 . A blade as claimed in  claim 9 , wherein the frame is foldable between a deployed state, in which the flexible sheet is deployed by the frame, and a folded state in which the flexible sheet is folded by the frame.  
   
   
       12 . A blade as claimed in  claim 11 , wherein the blade comprises a base and the frame comprises one or more ribs pivotably mounted on the base.  
   
   
       13 . A blade as claimed in  claim 12 , wherein the frame comprises a plurality of ribs, each rib being pivotable with respect to the base about a respective pivot axis.  
   
   
       14 . A blade as claimed in  claim 3 , wherein each pivot axis lies generally in said first plane.  
   
   
       15 . A blade as claimed in  claim 13 , wherein each pivot axis is obliquely disposed with respect to the, or each, other pivot axis such that, upon movement of the blade from the deployed state, the ribs converge with one another.  
   
   
       16 . A blade as claimed in  claim 12 , wherein the or each rib includes one or more pivot joints intermediate its ends.  
   
   
       17 . A blade as claimed in  claim 1 , comprising a locking mechanism for locking the blade in the deployed state.  
   
   
       18 . A blade as claimed in  claim 1 , wherein the blade is generally triangular in shape when in the deployed state.  
   
   
       19 . A blade as claimed in  claim 1 , wherein the blade is generally deltoid in shape when in the deployed state.  
   
   
       20 . A paddle comprising a shaft and a blade as claimed in  claim 1 .  
   
   
       21 . A paddle comprising a shaft and a blade, the blade comprising a frame supporting one or more flexible sheets.  
   
   
       22 . A paddle as claimed in  claim 21 , wherein the frame comprises a plurality of ribs extending radially with respect to the shaft.