Push Paddle

Abstract

A push-paddle has a buoyant wedge-shaped push-block attached to the bottom end of a pole. When pressed into the water wedge-end first, the push-block provides high drag and buoyant force for the user to push against and propel a watercraft using a punting-like motion. At the end of the power stroke, the wedge slips easily and quickly up out of the water allowing the user to recoil the push-paddle through the air.

1 . A push-paddle comprising a pole and a buoyant push-block wherein:
 a. the upper portion of the pole is a handle,   b. the bottom end of the pole is attached to the push-block,   c. the push-paddle has a pole axis defined as a line from the handle to the centroid of the push-block,   d. the push-block has a lateral axis perpendicular to the pole axis,   e. as viewed along the lateral axis, the push-block has a generally V-shaped portion with a thick back-end opposite a thin wedge-end,   f. the push-block has a broad bottom face forming a first side of the V-shaped portion,   g. the push-block has a top face forming the second side of the V-shaped portion,   h. the bottom face is opposite the handle and is angled to provide a large frontal area to resist downward and backwards motion of the push-block through the water when the push-block is oriented with the wedge-end down and is pushed in the direction of the pole axis; and,   i. as viewed along the lateral axis, the top face makes an obtuse angle to the pole axis so as not to catch and dig into the water as the push-block bobs up and is pulled forward to recoil the push-block through the air.   
     
     
         2 . The push-paddle of  claim 1  where the average angle of the V-shaped portion is between 10° and 50°. 
     
     
         3 . The push-paddle of  claim 1  having a final pole angle defined as the angle between the pole axis and the water surface when the V-shaped portion of the push-block is pointed wedge-end down, said final pole angle being between 10° and 50°. 
     
     
         4 . The push-paddle of  claim 1  in which the back-end of the push-block is gently rounded or chamfered toward the top face. 
     
     
         5 . The push-paddle of  claim 4  in which the push-block is airfoil-shaped. 
     
     
         6 . The push-paddle of  claim 1  in which the pole is adjustable-length. 
     
     
         7 . The push-paddle of  claim 1  in which the pole is detachable from the push-block for easier transport or stowage. 
     
     
         8 . The push-paddle of  claim 1  wherein the pole is adjustably attached to the push-block to allow variation in the angle of the pole axis relative to the push block as viewed along the lateral axis. 
     
     
         9 . The push-paddle of  claim 1  wherein the perimeter of the bottom face of the push block has one or more sharp edges, said sharp edges defined as being corner or chamfer radii less than 0.5 inch. 
     
     
         10 . The push-paddle of  claim 1  in which the push-block has sidewalls connecting the top face to the bottom face and closing the lateral ends of the V-shaped portion of the push-block. 
     
     
         11 . The push-paddle of  claim 10  in which sidewalls are angled, curved or chamfered inward toward the top face. 
     
     
         12 . The push-paddle of  claim 10  having flanges or lips where the sidewalls meet the bottom face. 
     
     
         13 . The push-paddle of  claim 1  in which the bottom face is concave. 
     
     
         14 . The push-paddle of  claim 1  in which the top face is convex. 
     
     
         15 . The push-paddle of  claim 1  wherein the push-block is made primarily of low-density closed-cell foam made by expanding one or more of the following polymers: polystyrene, polyethylene, polypropylene, polyurethane, PVC, and EVA. 
     
     
         16 . The push-paddle of  claim 15  having a skin or coating to protect or seal the foam, said skin or coating having higher density than the foam. 
     
     
         17 . The push-paddle of  claim 1  wherein the exterior of the push-block is blow-molded. 
     
     
         18 . The push-paddle of  claim 1  wherein the back-end is 3 to 5 inches thick. 
     
     
         19 . The push-paddle of  claim 1  wherein the maximum width of the bottom face is between 8 to 16 inches, measured parallel to the lateral axis. 
     
     
         20 . The push-paddle of  claim 1  wherein the push-block is between 7 and 14 inches high, measured from the wedge-end to the back-end. 
     
     
         21 . The push-paddle of  claim 1  wherein the push-block has a displacement of between 200 and 500 cubic inches. 
     
     
         22 . The push-paddle of  claim 1  wherein the back-end is 3 to 5 inches thick; the maximum width of the bottom face is between 8 to 16 inches, measured parallel to the lateral axis; the push-block is between 7 and 14 inches high, measured from the wedge-end to the back-end; and, the push-block has a displacement of between 200 and 500 cubic inches.