Waterpillar

Abstract

A pedal-powered aquatic vehicle is a positively buoyant aquatic vehicle with a lightweight frame and driven flotation wheels on either side of the occupant(s) seat. A pedal drive is incorporated into the lightweight frame to produce propulsion through a chain driven multi-geared system coupled with a drive shaft. Outer drive wheels rotate the flotation driven wheels to propel across water and level ground. Paddles are affixed to the driven flotation wheels. Steering linkages disengage drive wheels independently to provide steering.

What is claimed is:  
     
         1 . An aquatic vehicle comprising 
 A support frame having two end frames, connecting load transfer frames, and a seat/crank support frame    A seat supported in the support frame thereof:    A pedal drive mounted in front of said seat on said frame    An axle    A drive chain and sprocket affixed to and extending between said pedal drive and said axle.    A pair of drive wheels rotatably mounted at opposite ends of said axle    A pair of circular driven rails retained by outer frames of said support frame    A pair of flotation wheels attached to said circular driven rails    A set of paddles attached to each flotation wheel    A rigid linkage with dolly wheel pinned to each end frame    
     
     
         2 . An aquatic vehicle according to  claim 1 , wherein the flotation wheels are large enough to provide ample buoyancy for the entire vehicle with only a small portion of the wheel submerged which allows the drive force vector to be parallel with the contact surface.  
     
     
         3 . An aquatic vehicle according to  claim 1 , wherein paddles are mechanically connect to flotation wheels at a point just below the waterline for maximum thrust and efficiency.  
     
     
         4 . An aquatic vehicle according to  claim 1 , wherein the large flotation wheels replace displacement hulls as the means of flotation, thereby eliminating associated drag of fixed displacement hull(s).  
     
     
         5 . An aquatic vehicle according to  claim 3 , wherein the paddles are composed of buoyant material (such as a closed cell foam or other buoyant hydrophobic material) which assists in buoyancy without adding ballast as paddles typical to former art.  
     
     
         6 . An aquatic vehicle according to  claim 3 , wherein the paddles are easily detachable and replaceable by means of hook and loop strap or similar fastening device.  
     
     
         7 . An aquatic vehicle according to  claim 3 , wherein the paddles are oriented in a manner to provide the thrust vector parallel with the water surface without impeding land transport.  
     
     
         8 . An aquatic vehicle according to  claim 2 , wherein the flotation wheel construction is of inflatable bladder with fabric covering.  
     
     
         9 . An aquatic vehicle according to  claim 2 , wherein the flotation wheel construction is of rigid plastic, metal, or fiber composite construction.  
     
     
         10 . An aquatic vehicle according to  claim 1 , wherein the said drive wheel frictionally contacts and rotates the driven circular rail.  
     
     
         11 . An aquatic vehicle according to  claim 1 , wherein the said free-wheeling dolly wheel on each end frame is actuated by cable or mechanical linkage.  
     
     
         12 . An aquatic vehicle according to  claim 11 , wherein the said dolly wheel on each end frame, when actuated, disengages frictional contact between drive wheel and driven rail thus enabling differential steering due to the respective flotation wheel ceasing to be driven.  
     
     
         13 . An aquatic vehicle according to  claim 11 , wherein the said dolly wheel, when fully actuated, can be made to frictionally contact both the driven rail and the drive wheel at the same time thereby reversing rotation of the flotation wheel assembly.  
     
     
         14 . An aquatic vehicle according to  claim 13 , wherein fully actuating both said dolly wheels simultaneously will effectively drive the vehicle in reverse.  
     
     
         15 . An aquatic vehicle according to  claim 1 , wherein the end frame retains the driven hoop with guide rollers.  
     
     
         16 . An aquatic vehicle according to  claim 15 , wherein the guide roller axles function both as axles and as assembly pins for attachment of outer frames to connecting load transfer frames enabling collapsibility by minimizing mechanical complexity.  
     
     
         17 . An aquatic vehicle according to  claim 15 , wherein the axial load carrying rollers have an inside diameter such that the upper two load transfer frame members act as axles for the rollers, thereby eliminating the need for additional structure.  
     
     
         18 . An aquatic vehicle according to  claim 1 , wherein the said circular driven rail is mechanically attached to the driven flotation wheel.  
     
     
         19 . An aquatic vehicle according to  claim 1 , wherein the driven hoop and associated flotation wheel is removable/replaceable by removing a single guide roller (lower outer guide roller).  
     
     
         20 . An aquatic vehicle according to  claim 1 , wherein the said support frame is composed of metal tube.  
     
     
         21 . An aquatic vehicle according to  claim 1 , wherein the said support frame is composed of fiber laminate or polymer material.  
     
     
         22 . An aquatic vehicle according to  claim 1 , wherein the said pedal drive transmits power through a variable ratio transmission to enable appropriate power delivery on land and water.  
     
     
         23 . An aquatic vehicle according to  claim 1 , wherein the structure can be easily disassembled/deflated to enable it to be shipped in standard, low volume boxes.  
     
     
         24 . An aquatic vehicle comprising 
 A support frame having two end frames, connecting load transfer frames, and two seat/crank support frames    Two seats supported in the support frames thereof    An axle    Pedal drives mounted in front of said seats on said frames    Drive chains and sprockets affixed to and extending between said pedal drives and axle.    A pair of drive wheels rotatably mounted at opposite ends of said axle.    A pair of circular driven rails retained by outer frames of said support frame    A pair of flotation wheels attached to said circular driven rails    A set of paddles attached to each flotation wheel    A rigid linkage with dolly wheel pinned to each outer frame