Abstract:
An improved human powered watercraft propulsion device and mounting frame for attachment to existing pontoon watercraft. The propulsion device is light weight, self-contained, portable, has few moving parts made from corrosive resistant materials, and is propeller driven for quiet, efficient, and environmentally friendly underwater propulsion. Having a simple twisted belt configuration with an open structural design, all of the components are easily viewed and maintained by the user, as well as continuously cleaned, cooled, and lubricated by the water during operation, without the need for a sealed waterproof housing and internal oil bath. Hand knobs provide belt tensioning during operation and the device is adapted for operation by pedal, friction wheel, or direct chain drive. The device is adjustable on the attachment frame to fit the operator, pivots when beaching or striking an underwater object, and components such as pulleys and the propeller are changeable to achieve different power ratios.

Description:
COPYRIGHT NOTICE 
     A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever. 
     BACKGROUND 
     This invention relates to human powered watercraft propulsion devices, specifically portable, self-contained, pedal operated, belt driven units with hand adjustable belt tensioning that can be easily attached to small pontoon watercraft and water cycles to obtain forward and reverse water propulsion. 
     Inflatable pontoon fishing boats are plentiful and affordable in the marketplace. They are typically propelled by paddles, oars, kicking with foot fins, small electric trolling motors or small gasoline outboard motors. Human-powered watercraft propulsion devices are generally designed specifically for a particular watercraft, therefore, they are not easily attached to the wide variety of inexpensive inflatable pontoon boats and small watercraft available on the market. 
     Prior art reveals a variety of human powered watercraft propulsion devices. They are distinguished primarily by their design, portability, size, ease of use, connection to the watercraft, and the type of watercraft they are intended to fit. 
     U.S. Pat. No. 98,302 to Ross (1869), and U.S. Pat. No. 621,465 to Storms (1899), disclose a distributed system of pulleys and belts that require a lot of space on the watercraft. Both utilize a twisted belt design to transfer power from a crank shaft to a propeller shaft which have axes disposed at generally 90 degrees to each other. Ross (1869) uses hand cranks on a mono-hull boat, and Storms (1899) uses the foot pedals on a bicycle frame attached to a trimaran. Both systems are either permanently installed on a custom watercraft, or would require substantial effort and permanent modification of the watercraft to install. They are not easily portable or adaptable to other watercraft. Similarly, U.S. Pat. No. 5,807,148 to Siviero (1998), teaches a drive unit attached to the front of a bicycle on a pontoon boat driven by a flexible cable from a friction wheel in contact with the rear wheel of a bicycle. Though the drive unit itself is small, the entire system is very distributed and large. It requires a bicycle and a custom pontoon boat, so it is not easily portable to other pontoon watercraft. None of the above devices are self-contained or easily transferable to other watercraft. 
     U.S. Pat. No. 8,342,897 B2 to Gater and Banks (2013), reveals a similarly large, bulky, distributed system, but it is designed to be mounted in an existing canoe or similar type watercraft. The system includes a seat, frame, and attachment system, and utilizes a combination of twisted and non-twisted belts and a flexible shaft. It has many parts, is not easily removed, and not designed for attachment to a small pontoon watercraft. 
     U.S. Pat. No. 5,405,275 to Schlangen and Buresch (1995) and U.S. Pat. App. Publication No. US 2008/0188146 A1 to Howard and Wilcoxen (2008), disclose self-contained propulsion devices. They utilize non-twisted chain and bevel gears sealed inside a waterproof housing with an oil bath to lubricate the internal mechanisms. The device of Schlangen and Buresch (1995) is specifically fitted to its custom pontoon watercycle, and likewise, the device of Howard and Wilcoxen (2008) is specifically designed for and attached to its custom kayak. They are both designed to be attached specifically to their respective watercraft and are not easily removable or transferable to different types of watercraft without modification to the drive or watercraft. Their closed systems have many internal parts, are likely expensive to produce, require a waterproof sealed lining with an oil bath, cannot be visually inspected by the user without disassembly, and require periodic maintenance of the oil bath and internal components. 
     U.S. Pat. No. 6,712,653 B2 to Free (2004), is a self-contained, portable propulsion device utilizing a twisted chain configuration that is designed to be either enclosed in a housing or fully exposed and to be installed in a daggerboard fashion. It would likely require a custom boat or specific modification to the boat or drive unit to be installed, and is relatively complex with many moving parts. 
     In conclusion, in so far as I am aware, no human powered watercraft propulsion device formerly developed provides a portable, self-contained, removably attachable, efficient, and affordable water propulsion device for attaching to existing inflatable pontoon boats and other small watercraft. 
     ADVANTAGES 
     Accordingly several advantages of one or more aspects are as follows: an improved, self-contained, human powered watercraft propulsion device and mounting frame that can be readily attached to existing inflatable pontoon boats and other small watercraft. Having a simple, lightweight, portable design, and also having few moving parts, made with corrosive resistant materials including plastic, stainless steel, or aluminum. The propulsion device is durable, economical, and practical. Utilizing human power from the leg muscles, the user provides pedal operated, belt actuated, propeller driven, underwater propulsion that is quiet, efficient and environmentally friendly. The propulsion device employs a simple twisted belt configuration to compensate for the 90 degree difference in axial alignment between the drive shaft and the propeller shaft, and has an open architecture design allowing all of the components to be easily viewed, inspected, cleaned and maintained by the operator, as well as being continuously cleaned, cooled and lubricated by the water during operation. The open design with corrosive resistant components also alleviates the need for a watertight, sealed drive unit with an oil bath to lubricate internal drive components, like other prior art drive systems. The drive unit is small, self-contained, and provides forward and reverse propulsion. It pivots in an arc rearward and upward in case of contact with underwater obstacles, or in cases when it is desired to be lifted above the water by the operator. The propulsion device is customizable by changing the sizes of the pulleys or the size and design of the prop to achieve different gear ratios and thrust, or the length of the belt to change the overall height of the drive unit. A shrouded propeller offers improved thrust, strength, and safety, as an alternative to the sharp and exposed tips of standard bladed propellers. The attachment frame allows the propulsion device to be easily and securely mounted to commercially available pontoon fishing boats. The distance from the propulsion device to the boat seat, as well as the height of the device from the water is adjustable by the user for optimum placement and comfort. The propulsion device is adaptable to be driven by pedals, a sprocket for direct chain connection to a bicycle or other chain driven device, or by friction wheel from a bicycle wheel or other source. It can be placed on various types of watercraft in its various embodiments. 
     The result is a self-contained, human powered watercraft propulsion device that is adaptable and portable across multiple types of watercraft and overcomes many limitations of prior art to produce a simple, efficient and affordable means of water propulsion for recreation, sport and meaningful travel over the water. 
     Other advantages of one or more aspects will be apparent from a consideration of the drawings and ensuing description. 
     SUMMARY 
     In accordance with one embodiment a portable, self-contained, human powered water propulsion device for a variety of pontoon watercraft. 
    
    
     
       DRAWINGS 
       Figures 
         FIG. 1 : Top right rear perspective view of propulsion device. 
         FIG. 2 : Bottom right rear perspective view of upper housing. 
         FIG. 3 : Top right front perspective view of inside of upper housing. 
         FIG. 4 : Top right rear perspective view of upper housing with pedal and crank arm removed to show flanged sleeve bearing in the wall of upper housing with drive shaft running through it. 
         FIG. 5 : Top right rear perspective view of attachment frame. 
         FIG. 6 : Top right front perspective view showing propulsion device and attachment frame. 
         FIG. 7 : Top right front perspective view showing propulsion device and inflatable pontoon boat. 
         FIG. 8 : Top right rear perspective view showing rudder attached to propulsion device. 
         FIG. 9 : Top right rear perspective view showing sprocket on drive shaft. 
         FIG. 10 : Top right front perspective view showing two spaced apart friction wheels. 
         FIG. 11 : Top right front perspective view showing side-by-side friction wheels. 
         FIG. 12 : Right side view of a bicycle. 
     
    
    
     
       
         
               
             
               
               
               
               
               
             
           
               
                   
               
               
                 DRAWINGS - REFERENCE NUMERALS 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 20 
                 Upper Housing 
                 21 
                 Upper Housing Shell 
               
               
                   
                 22 
                 Handle 
                 23 
                 Upper Pulley 
               
               
                   
                 24 
                 Channel 
                 25 
                 Pivot Pin Hole 
               
               
                   
                 26 
                 Drive Shaft 
                 27 
                 Crank Arm 
               
               
                   
                 28 
                 Pedal 
                 29 
                 Thru Knob 
               
               
                   
                 30 
                 Front Adjusting Tube 
                 31 
                 Rear Adjusting Tube 
               
               
                   
                 32 
                 Endless Loop 
                 33 
                 Lower Unit 
               
               
                   
                 34 
                 Belt Restrictor 
                 35 
                 Lower Pulley 
               
               
                   
                 36 
                 Skeg 
                 37 
                 Propeller 
               
               
                   
                 38 
                 Propeller Shaft 
                 39 
                 Belt Guide 
               
               
                   
                 40 
                 Front Tube Support 
                 41 
                 Rear Tube Support 
               
               
                   
                 42 
                 Locknut 
                 43 
                 Threaded End 
               
               
                   
                 44 
                 Flanged Sleeve Bearing 
                 45 
                 Attachment Frame 
               
               
                   
                 46 
                 Boat Frame Extension Tube 
                 47 
                 Cross Bar 
               
               
                   
                 48 
                 Adjusting Bracket 
                 49 
                 Lift Tube 
               
               
                   
                 50 
                 Pin 
                 51 
                 Pontoon Boat 
               
               
                   
                 52 
                 Boat Frame 
                 53 
                 Boat Seat 
               
               
                   
                 54 
                 Pontoon 
                 55 
                 Rudder 
               
               
                   
                 56 
                 Rudder Blade 
                 57 
                 Rudder Shaft 
               
               
                   
                 58 
                 Skeg Extension 
                 59 
                 Tiller 
               
               
                   
                 60 
                 Sprocket 
                 61 
                 Friction Wheel 
               
               
                   
                 62 
                 Bicycle 
                 63 
                 Bicycle Chain 
               
               
                   
                 64 
                 Driven Wheel 
               
               
                   
               
             
          
         
       
     
     DETAILED DESCRIPTION 
     One embodiment of the watercraft propulsion device is illustrated in  FIG. 1  showing an upper right rear perspective view of upper housing  20 , comprising upper housing shell  21  with pivot pin hole  25  through channel  24 , with handle  22 . Upper housing  20  supports drive shaft  26 , which runs thru upper pulley  23 , connected on both ends to crank arms  27  with pedals  28 . Upper pulley  23  is partially encircled by endless loop  32 , which partially encircles lower pulley  35  coupled to propeller shaft  38 , and attached to propeller  37 . Front adjusting tube  30  and rear adjusting tube  31 , with thru knobs  29 , connect to lower unit  33 , with integrated belt restrictor  34  and skeg  36 . 
       FIG. 2  illustrates a lower right rear perspective view of the watercraft propulsion device showing upper housing  20  with front tube support  40 , rear tube support  41 , endless loop  32 , and belt guide  39 . 
       FIG. 3  illustrates an upper right front perspective view of the inside of upper housing  20  with rear tube support  41 , locknut  42  on threaded end  43 , with handle  22 , crank arm  27  and pedal  28 . 
       FIG. 4  illustrates an upper right rear perspective view of upper housing  20  showing drive shaft  26  running through flanged sleeve bearing  44 . 
       FIG. 5  illustrates an upper right rear perspective view of attachment frame  45  with boat frame extension tubes  46  coupled to cross bar  47 , adjusting bracket  48 , lift tube  49 , and pins  50 . 
       FIG. 6  illustrates an upper right front perspective view of attachment frame  45 , channel  24 , lift tube  49  and pins  50 . 
       FIG. 7  illustrates an upper right front perspective view of pontoon boat  51 , having boat frame  52 , pontoons  54 , boat seat  53 , with attachment frame  45  and pin  50 . 
     Another embodiment of the watercraft propulsion device is illustrated in  FIG. 8  showing an upper right rear perspective view of rudder  55  connected to upper housing  20  and lower unit  33 , with rudder blade  56 , rudder shaft  57 , handle  22 , tiller  59 , and skeg extension  58 . 
     An alternative embodiment of the watercraft propulsion device is illustrated in  FIG. 9  showing an upper right rear perspective view of upper housing  20 , drive shaft  26  with sprocket  60  in place of crank arms  27  and pedals  28  (not shown). 
     Another alternative embodiment of the watercraft propulsion device is illustrated in  FIG. 10  showing an upper right front perspective view of upper pulley  23  (not shown) positioned between two spaced apart friction wheels  61 . 
     Another alternative embodiment of the watercraft propulsion device is illustrated in  FIG. 11  showing an upper right front perspective view of upper pulley  23  positioned to one side of two side-by-side friction wheels  61 , to provide a larger single friction wheel surface without a space in between the friction wheels  61 . 
       FIG. 12  illustrates a right side view of bicycle  62  showing bicycle chain  63  and driven wheel  64 . 
     Operation— FIGS. 1-7   
     Pedals  28  are coupled to crank arms  27  which turn drive shaft  26  running through flanged sleeve bearing  44  ( FIG. 4 ) through the sides of upper housing shell  21  to rotate upper pulley  23 , pulling endless loop  32  around upper pulley  23  and lower pulley  35  to rotate propeller shaft  38 , driving propeller  37  in a circular motion providing propulsion through the water. Note that reverse rotation by the operator on pedals  28  will result in reverse propulsion as expected. 
     Belt guide  39  ( FIG. 2 ) on the bottom end of upper housing  20 , and belt restrictor  34  on the top end of lower unit  33 , guide and restrict endless loop  32  over upper pulley  23  and lower pulley  35  so endless loop  32  will align and track correctly over the pulleys. 
     Front and rear adjusting tubes,  30  and  31 , respectively, are joined to lower unit  33  on the lower ends, and adapted with threaded ends  43  ( FIG. 3 ) on the upper ends. A thru knob  29  is twisted onto each of the upper threaded ends  43  of front and rear adjusting tubes,  30  and  31 , respectively, until enough of each of the front and rear adjusting tubes,  30  and  31 , respectively, are able to slide through holes in front and rear tube supports,  40  and  41 , respectively, thereby joining upper housing  20  and lower unit  33  together, with front and rear tube supports,  40  and  41  respectively, resting on top of and are supported from below, by thru knobs  29 . While endless loop  32  is connected to upper and lower pulleys,  23  and  35 , respectively, thru knobs  29  are turned by the operator to rotate on the threaded ends  43  of front and rear adjusting tubes,  30  and  31 , respectively, to adjust the distance between upper housing  20  from lower unit  33 , thereby adjusting the distance separating upper and lower pulleys,  23  and  35 , respectively, allowing the operator to adjust the proper tensioning of endless loop  32  while in operation, for optimized performance of the drive unit. A locknut  42  is threaded onto the top end of each threaded end  43  on the portion of the front and rear adjusting tubes,  30  and  31 , respectively, that protrudes above the front and rear tube supports,  40  and  41 , respectively, leaving enough space between the bottom of locknuts  42  and the top of front and rear tube supports,  40  and  41 , respectively, to allow ample room for loosening and tensioning endless loop  32  as desired. The purpose of the locknuts  42  is to retain the front and rear adjusting tubes,  30  and  31 , respectively, in connection with upper housing  20  in the event endless loop  32  is severed or loosened to the point it can no longer hold upper housing  20  and lower unit  33  together in tension. 
     Handle  22  allows the propulsion device to be easily carried independent of the watercraft as well as providing a grip for manipulating the device in a tilting manner while installed on a watercraft. 
     Attachment frame  45  ( FIG. 5 ) is connected to a pontoon boat  51  by inserting the boat frame extension tubes  46  into the existing open-ended tubes of boat frame  52  and fixing in place with pins  50 . The propulsion device is connected to attachment frame  45  by coupling channel  24  to lift tube  49  with pin  50  thru pivot pin hole  25 . Channel  24  straddles lift tube  49 , surrounding it on three sides to prevent the propulsion device from twisting side-to-side while pedaling, while also allowing it to rotate about the axis of pivot pin hole  25  so the propulsion device will tilt up when beaching, striking an underwater obstacle, or when lifted manually by the operator as desired to raise or lower the device. 
     The height of the drive unit is selectively adjustable by moving lift tube  49  up or down in adjusting bracket  48 . The distance of pedals  28  from boat seat  53  is selectively adjustable by sliding boat frame extension tubes  46  in and out of the main tubes of boat frame  52  until the distance is comfortable for the operator, pinning in place with pins  50 . 
       FIG. 8 —Additional Embodiment with Rudder 
     An additional embodiment includes a rudder  55  removably attached to the propulsion device for steering. Rudder shaft  57  runs through holes in handle  22  at the top, and is connected at the bottom to skeg extension  58  which is fixed to skeg  36  ( FIG. 1 ). The rudder blade  56  is turned by moving tiller  59  to either side as desired. 
       FIGS. 9 &amp; 12 —Alternative Embodiment with Sprocket 
     An alternative embodiment removes pedals  28  and crank arms  27 , and couples a sprocket  60  to drive shaft  26 , allowing the propulsion device to be powered by a chain  63  from a bicycle  62 , or other chain driven mechanism. 
       FIGS. 10 &amp; 12 —Alternative Embodiments with Friction Wheels 
     Another alternative embodiment removes pedals  28  and crank arms  27 , and couples two spaced apart friction wheels  61  to drive shaft  26 , with upper pulley  23  (not shown) centered between the two friction wheels  61 , allowing the propulsion device to be powered by a driven wheel  64  of a bicycle  62 , or other driven wheel as may be appropriate. This embodiment is appropriate for wide wheeled bicycles, like mountain bikes, and other wide driven wheels. 
       FIGS. 11 &amp; 12 —Alternative Embodiments with Friction Wheels 
     Another alternative embodiment removes pedals  28  and crank arms  27 , and couples one or more friction wheels  61  to drive shaft  26 , in a side-by-side configuration with upper pulley  23  coupled to drive shaft  26  on either side of friction wheels  61 , allowing the propulsion device to be powered by a driven wheel  64  of a bicycle  62 , or other driven wheel as may be appropriate. This embodiment is appropriate for narrow wheeled bicycles, like road bikes, and other narrow driven wheels. 
     CONCLUSION, RAMIFICATIONS AND SCOPE 
     Thus the reader can see that at least one embodiment of the propulsion device and mounting frame produces a simple and effective device for providing human powered water propulsion for small pontoon boats and water cycles. 
     While the above description contains many specifics, these should not be construed as limitations on the scope, but rather as an exemplification of one or more embodiments thereof. Many other variations of size, material, shape, and configurations are possible. For example, the upper housing can take a variety of shapes and can be adapted to pedal, sprocket or friction wheel as a means of providing rotation to the drive shaft. The size of many components, such as pulleys, belts, chains, friction wheels, sprockets, knobs, and crank arms can vary. The number and arrangement of friction wheels could vary, for example, to use one or several friction wheels either spaced apart with one or more pulleys in the middle, or with a pulley to either side of one or several friction wheels positioned side-by-side. A variety of suitable structural materials could be employed, including steel, aluminum, plastic, wood, composites, and carbon fiber. And a variety of propeller types, styles, number of blades, and blade pitch could be used. Bearings could be comprised of various materials, and could be sleeve bearings or other types of bearings mounted on the upper housing or inserted into the wall of the upper housing, or no bearings at all if the material used for the upper housing, lower unit, and other components permit. And the propulsion device could be attached to various types and configurations of watercraft, including pontoon boats, water cycles, and amphibious cycles. 
     Accordingly, the scope should be determined not by the embodiments illustrated, but by the appended claims and their legal equivalents.