Patent Publication Number: US-8529306-B2

Title: Device for pedal powering a watercraft

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to provisional application No. 61/402,792 filed on Sep. 7, 2010. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT 
     Not Applicable 
     REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     The present invention relates to the propulsion of watercraft and specifically to an apparatus to be mounted to accommodating watercraft that will allow for pedal powered propulsion by an occupant. 
     Various means of occupant-powered watercraft have been proposed and utilized in the past. Paddles driven by hand, including those with folding blades, such as the device described in U.S. Pat. No. 427,842, have been around for many years. More recently, foot-driven, pedal systems have gained in popularity as boaters have come to appreciate the advantages of having their hands free for activities, such as, fishing. The typical superiority of an operator&#39;s leg strength over arm strength is another reason for the appeal of pedal systems. 
     Many previously proposed and existing devices for pedal driving watercraft rely on a circular pedal motion like that used to propel bicycles. U.S. Pat. No. 5,460,551 describes a pedal driven watercraft that requires pedals to be driven in such a revolving path. For the operator of a small watercraft, such as, a kayak this circular motion may produce discomfort due to the relative distance between a given pedal&#39;s nearest and furthest points to the operator&#39;s torso during a revolution. Many of these designs also require chains, or extended drive shafts to transfer motion to a propulsive element. 
     The device described in U.S. Pat. No. 6,022,249 requires less of an extension of the operator&#39;s legs, but lacks the desirable feature of being able to reverse the direction of the propulsion. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention relates to occupant powered propulsion of a watercraft, and specifically to a pedal driven apparatus that may be mounted to vessels, such as, kayaks that have been specifically designed or altered to accommodate the device. 
     The present invention creates propulsion by providing a means by which the leg motion of an occupant can move paddles with hinged blades, below the waterline. For the purposes of this document the paddles with hinged blades will be referred to as folding paddles. 
     Folding paddles are configured so that they fold shut, producing minimal resistance when moving in the direction of travel of a host watercraft and open when moving opposite the direction of travel of a host watercraft, thus providing thrust. 
     The preferred embodiment employs two levers to convert the leg movement of the occupant to propelling thrust. (For the purposes of this document, the term, “operator,” may be used interchangeably with the term, “occupant.”) Each of the two levers has a foot pedal mounted to the end of its force arm, and a folding paddle mounted to the end of its resistance arm. 
     For each lever the pivot point or fulcrum is provided by a shaft running through a bushing attached to a common mounting plate. Near the center of the mounting plate the two shafts, lying parallel are connected by meshed gears so that the rotation of one shaft creates an equal counter-rotation in the other. 
     When properly mounted to a vessel the mounting plate is attached to a deck, floor, or similarly horizontal, structural plane of the craft at a level above the waterline. Two parallel slots penetrating the hull are required to allow the levers to reach from above to below the level of the waterline. The upper rim of the slots must be above the water line to prevent the vessel from taking on water. 
     The device is intended to be mounted on the longitudinal centerline between the bow and the occupant&#39;s seat, at a distance from the seat that will allow for a comfortable, back-and-forth pedaling motion by the occupant. 
     When force is applied to a given pedal it will travel roughly 120 degrees in an arc from its closest to furthest point from the operator. As a given pedal moves away from the operator, its corresponding folding paddle is open and moving towards the operator, below the water line, creating thrust. Simultaneously, the other pedal is being brought back towards the operator and its paddle is folded and moving away from the operator. 
     Repetition of the movement described above propels the host craft through the water in a forward direction. 
     A hinged connection between each lever and its fulcrum or shaft allows the lever arms to be rotated 180 degrees. The occupant can flip the pedals with his or her feet, rotating the folding paddle blades. With the paddles facing in the opposite direction, the same back-and-forth pedal motion will move the craft in reverse. 
     Since maintaining a low center of gravity is desirable in many small types of watercraft, pedaling from a recumbent position is often a necessity in pedal driven watercraft. The back-and-forth motion applied toward the present invention requires less leg reach than revolving, bicycle-type pedals. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
         FIG. 1  is a port side elevation of one embodiment of the present invention with components configured for forward propulsion. Arced arrows indicate the direction of movement of pedals and folding paddles. 
         FIG. 2  is a port side elevation of the embodiment of  FIG. 1  with components configured for reverse propulsion. Arced arrows indicate the direction of movement of pedals and folding paddles. 
         FIG. 3  is a bow elevation of the embodiment of  FIG. 1  with components configured for forward propulsion. 
         FIG. 4  is a bow elevation of the embodiment of  FIG. 1  with components configured for reverse propulsion. 
         FIG. 5  is a partial plan detail of the embodiment of  FIG. 1  showing the arrangement of shafts, gears, bushings and mounting plate. Pedals, levers, lever extensions, and folding paddles have been omitted to lend visual clarity. 
         FIG. 6  is a detail plan of a folding paddle of the embodiment of  FIG. 1  in an open, propulsive configuration. 
         FIG. 7  is a detail plan of a folding paddle of the embodiment of  FIG. 1  in a closed, streamlined configuration. 
         FIG. 8  is a port elevation of the embodiment of  FIG. 1  as mounted on a host watercraft with an occupant. 
         FIG. 9  is a plan of the embodiment of  FIG. 1  as mounted on a host watercraft with an occupant. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Turning to the drawings, it is important to note that when properly mounted to a host craft  16  as in  FIG. 9  the present invention is mostly symmetrical across the center line, between port and starboard, allowing distinction to be made between like parts based upon their location relative to the host craft. 
     Referring to the drawings, the present invention relates to a pedal powered propulsion device for a watercraft comprised of first-class levers, port  1  and starboard  2 , rotatable shafts, port  5  and starboard  6 , shaft extensions port  5   a  and starboard  6   a , folding paddles, port  13  and starboard  14 , rotatable pedals port  3  and starboard  4 , hinges, port  7  and starboard  8 , bushings, port  9  and starboard  10 , gears, aft  11  and fore  12  and a mounting plate  15 , 
       FIG. 1  shows a port side elevation, of the preferred embodiment, with pedals  3  and  4  and folding paddles  13  and  14  oriented for forward propulsion of a host craft. 
       FIG. 3  represents a front elevation, of the preferred embodiment with the orientation of the pedals and folding paddles indicative of forward motion of the host craft. 
     In  FIG. 3  it can be seen that the port shaft  5  and starboard shaft  6 , mounted in bushings  9  and  10  act as fulcrums for their respective levers; each lever having resistance arms extending in generally downward directions from, their respective shafts and force arms extending in generally upward directions from their respective shafts. 
     In the plan detail of  FIG. 5  it can be seen that shaft  5  has a gear  10  mounted at a point near the center of the mounting plate  15  and that shaft  6  has a gear  12  mounted at a point near the center of the mounting plate  15 . The two gears are meshed forming a simple gear train. 
     The relative angles of the port lever  1  and starboard lever  2  at their terminal points of travel is locked by the simple gear train described above and depicted in the plan detail,  FIG. 5 . 
     Taken together  FIG. 1  and  FIG. 3  provide clear illustration of the orientation of parts of the invention when configured for forward propulsion. It can be seen that the first-class levers  1  and  2  are hinged to and align themselves behind the 90 degree shaft extensions  5   a  and  6   a  and that the rotatable pedals  3  and  4  mounted at 90 degrees to the levers, project in towards one another. 
       FIGS. 1 and 3  also depict the configuration of folding paddles  13  and  14 . In  FIG. 1  and in  FIG. 3  the port folding paddle  13  is depicted as open and the starboard folding paddle  14  is depicted as closed. Given the indicated direction of travel in  FIG. 1  it should be evident that the open configuration of a folding paddle as represented in the plan detail  FIG. 6  provides the thrust that propels the host watercraft, while the folded configuration represented in plan detail in  FIG. 7  presents minimal resistance through the water as a folding paddle moves in the direction of travel of a host craft  16 . 
     Given the orientation of comprising parts illustrated in the figures described above the following manner of operation for forward propulsion can be understood: 
     Taking the orientation of parts in  FIG. 1  as a beginning point, pressure applied by an operator&#39;s foot to the starboard pedal  4  in a direction towards the bow will result in a number of simultaneously occurring actions related to the desired function of the invention. 
     On the starboard side of the device the force arm of the starboard lever  2  with attached pedal  4  will move in an arcuate path toward the bow of the host craft, while the resistance arm of the starboard lever  2  with attached folding paddle  14  will move in an arcuate path toward the stem of the host craft. Given the direction of movement of the starboard folding paddle  14  relative to the location of the hinged edge of said paddle, the resulting water pressure will force open the blades forming a propulsive orientation. 
     In the center portion of the device, the counter-clockwise motion of the starboard shaft  6  is converted to clockwise rotation in port shaft  5  by the gear train created by the meshed gears  11  and  12 . 
     On the port side of the device the force arm of the port lever  1  with attached pedal  3  will travel in an arcuate path towards the stem, driven by the force applied to starboard pedal  4 , transferred and reversed in the gear train as described above. The resistance arm of the port lever  1  with attached folding paddle  13  will travel in an arcuate path toward the bow with the resulting water pressure forcing closed the blades of the paddle, creating a streamlined orientation. 
     When the starboard pedal  4  reaches its predetermined, terminal point of travel, pressure is applied to port pedal  3 , making folding paddle  13  the thrust paddle and folding paddle  14  the passive, streamlined paddle. 
     Repetition of the action described above propels a host craft in a forward direction through the water. 
     Reverse propulsion is achieved by changing the orientation of the pedals from pointing in towards one another as in  FIG. 3  to pointing in opposite directions as seen in  FIG. 4 . This alteration can be achieved by the operator using feet or hands. 
     The port side elevation in  FIG. 2  and the front elevation of  FIG. 4  show the preferred embodiment, with pedals  3  and  4  and folding paddles  13  and  14  oriented for reverse propulsion of a host craft. 
     It can also be seen in  FIG. 2  and in  FIG. 4  that the levers  1  and  2  fall along side of their respective shaft extensions  5   a  and  6   a  when configured for reverse propulsion. 
     Since the rotating pedals  3  and  4  are fixed to the levers  1  and  2  and the levers  1  and  2  are connected to the shaft extensions  5   a  and  6   a  with hinges  7  and  8 , flipping the orientation of the pedals  3  and  5  by 180 degrees also flips the direction of the folding paddles  13  and  14  by 180 degrees. With the leading edge of each folding paddle  13  and  14  facing the stern of the host craft  16  pressure applied to the pedals will propel a host craft in a reverse direction. 
     While a preferred embodiment of the present invention has been described in some detail above, it should be understood by those skilled in the art that other configurations of similar elements could be applied without departing from the spirit or scope of the present invention. The present invention is not limited except as by the appended claims.