Abstract:
A diver lying prone in the water grasps the invention with his hands and pushes on pedals with his feet. The pedal motion is converted into propulsive force that moves the diver through the water. The diver is free to bend at his hip joints and bend and twist his spine to cause turns, dives and ascents in the water. The preferred embodiment of the propulsion means comprises a simple direct drive of an arm. As the diver operates the pedals the forward end of the arm pivots with respect to the device as the rearward end of the arm sweeps back and forth in the water. A fin is attached to the rearward end of the arm. The fin is fitted with a simple device for controlling the angle of attack of the fin with respect to the flow of water past it.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not Applicable. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable. 
     REFERENCE TO A MICROFICHE APPENDEX 
     Not Applicable. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to devices wherein means are provided to propel a diver through a body of water with which he is in direct contact. 
     2. Description of the Prior Art 
     Several devices for propelling a diver through a body of water with which he is in direct contact are provided in prior art. 
     U.S. Pat. No. 3,323,481 to Harvey (1967) discloses a swimming appliance that is applied to a swimmer as a “pack” or a “ruck sack” using straps or a harness. Steerage by a swimmer is achieved by using the hands or feet as rudders or paddles. A motor drives a propeller or an impeller or a water jet to propel the swimmer through the water. 
     U.S. Pat. No. 3,768,431 to Picken (1973) discloses a manually operated underwater swimming aid for use in propelling a diver or swimmer below the surface of the water. The aid facilitates such propulsion through oscillating motion imparted by the diver to a pair of resilient planar blades. The blades are anchored to an axial support. Handles are provided rearward of the support for gripping by the swimmer. Subsequent manual application of oscillating torque forces to the handles about the longitudinal axis of the aid flex the blades into a propeller configuration to pull the diver through the water. 
     U.S. Pat. No. 6,033,276 to Han (2000) discloses a personal water vehicle comprising a structure for supporting a person in a prone position above an upper surface of a body of water. A facility is for steering the supporting structure in the body of water using manual operation by the hands of the person. An assemblage is for propelling the supporting structure in the body of water, using peddle movement by the feet of the person A device for viewing, extends through the supporting structure so that the person can look into the body of water. Furthermore, the propelling assemblage comprises a swivel pedal assembly, pivotally mounted over the rearward end of the supporting structure at the tail fin assembly. A pair of toe clip foot hanger pedals are provided with each mounted on an opposite end of the swivel pedal assembly, to engage with one foot of the person. A propulsion gear box is carried in the tail fin assembly in conjunction with the steering gear unit. When the swivel pedal assembly is rocked forward and rearward by the peddle movement of the feet of the person engaging the toe clip foot hanger pedals, the tail fin assembly will undulate like a fish tail in the body of water to drive the supporting structure forward in the body of water. 
     While the buoyant underwater viewing device disclosed by Han is suitable for traveling on the upper surface of a body of water and looking into the water, it is unsuitable as a diving device because of its buoyancy and lack of means for initiating dives and ascents in a body of water. It uses hand operated mechanical means to execute turning movements in the plane of the upper surface of the water. It uses adjustable shoulder support pad assemblies to provide the reactive force from the vehicle that allows the vehicle operator to apply force to the pedals with his feet. It furthermore does not provide a means to control the angle of attack of the tail fin with respect to the flow of water past it to prevent stalling that can drastically reduce the propulsive force. 
     U.S. Pat. No. 5,401,196 to Triantafyllou et al (1995) discloses a propulsion system for use in a fluid, the system utilizing at least one foil which is both oscillated at a frequency f with an amplitude a in a direction substantially transverse to the propulsion direction and flapped or pitched about a pivot point to change the foil pitch angle to the selected direction of motion with a smooth periodic motion. Parameters of the system including Strouhal number, angle of attack, ratio of the distance to the foil pivot point from the leading edge of the foil to the chord length, the ratio of the amplitude of oscillation to the foil chord width and the phase angle between heave and pitch are all selected so as to optimize the drive efficiency of the foil system. Further, while a motor or engine-driven vehicle has been assumed for the preferred embodiment, the invention may also be advantageously utilized in human powered systems with motions of a swimmer&#39;s legs being converted by suitable mechanical linkages into heave and pitch motion for one or more foils in accordance with the teachings of this invention. Such devices can provide faster motion with less exertion than currently available systems for propelling a swimmer or diver without a drive motor. 
     For good performance the marine propulsion system disclosed by Triantafyllou et al requires regulation of a large number of parameters in addition to the angle of attack of a foil with respect to the flow of water past it to prevent stalling. In particular, the dynamic parameter of phase angle between heave and pitch needs to be simultaneously regulated with angle of attack. 
     BRIEF SUMMARY OF THE INVENTION 
     A diver lying prone in a body of water grasps the present invention with his hands and pushes on pedals with his feet. The arms of the diver transmit the reactive force from the device that allows the feet of the diver to apply force to the pedals. The pedal motion is converted into propulsive force that moves the diver through the water. The device is configured so that it can be adjusted to divers of varying body dimensions so that a diver is free to bend at his hip joints and bend and twist his spine so as to use his torso as a control foil to cause turns, dives and ascents in the water. The diver can rapidly and easily mount and dismount the device while in the water by grasping or releasing the device with his hands and applying or removing his feet from the pedals. The device is intended to be made with a small positive buoyancy which can be reduced or made negative by addition of weights. The preferred embodiment of the propulsion means comprises a simple direct drive of an arm. As the diver operates the pedals the forward end of the arm pivots with respect to the device as the rearward end of the arm sweeps back and forth in the water. A fin is attached to the rearward end of the arm. The fin is fitted with a simple device for controlling the angle of attack of the fin with respect to the flow of water past it to prevent stalling. 
     The diver may be equipped with a snorkel, an underwater breathing apparatus; or the diver may free dive without such breathing aides. 
     The primary object of the present invention is a device wherein means are provided to propel a diver through a body of water with which he is in direct contact that will overcome the shortcomings of the prior art devices. Objects and advantages of the present invention are: 
     (a) to provide motive power by applying the force of the leg muscles of a diver to pedals. 
     (b) to provide means for executing dives, ascents and turns in a body of water by using the torso of the body of a diver as a control foil. 
     (c) to facilitate diving with the device by limiting its buoyancy. 
     (d) to provide for the transmission of the reactive force of the device that allows a diver to apply force to the pedals by the diver grasping the device with his hands. 
     (e) to provide, in the preferred embodiment of the means for propulsion, control of the angle of attack of the tail fin with respect to the flow of water past it to prevent stalling without complicated regulation of other parameters. 
     A further objective is to reduce the complexity of the device so that the device is simple and easy to use, reliable, and economical in cost to manufacture. 
     Further objects and advantages of the invention will appear from consideration of the ensuing drawings and detailed description. 
     To the accomplishment of the above and related objects, this invention may be embodied in the form illustrated in the accompanying drawings, attention being called to the fact, however, that the drawings are illustrative only, and that changes may be made in the specific construction illustrated and described within the scope of the appended claims. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     FIG. 1 is a top view of a person positioned in the preferred embodiment of the present invention for operation thereof in accordance with the teachings of this invention. 
     FIG. 2 is a side view taken in the direction of arrow  2  in FIG.  1 . 
     FIG. 3 is a front view taken in the direction of arrow  3  in FIG.  2 . 
     FIG. 4 is a partial top view of the present invention showing the modifications comprising of the invention, 
     FIG. 5 is a partial side view showing the modifications comprising the modified form of the invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to FIGS. 1-3, a device  12  for propelling a diver  13  through a body of water with which he is in direct contact is shown. The forward part of device  12  is a streamlined strut  14  in which there are a pair of handholds  15  into which diver  13  inserts his hands to grasp device  12 . Diver  13  holds strut  14  with straight arms so that its leading edge is rearward of the hip joints of diver  13 , which allows diver  13  to bend and twist his torso at his hip joints and along his spine. With forward motion of device  12  and diver  13 , bending torso of diver  13  initiates pitch maneuvers that result in dives or ascents in the water. Rotating the spine of diver  13  initiates roll maneuvers that, when subsequently combined with a pitch maneuver, result in a turning in the plane parallel to the water&#39;s surface. 
     A rigid structure  16  connects strut  14  to the means of propelling device  12  and diver  13  through the water. Device  12  and diver  13  are propelled through the water by diver  13  pushing on a pair of pedals  17  located on opposite sides of connecting structure  16 . Diver  13  pushes alternately with one foot and then the other on pedals  17 . A transmission converts the pedaling motion into back and forth rotation of swivel arm  18  about axle  19 . Axle  19  is pivotably mounted to connecting structure  16  so that swivel arm  18  rotates in the plane that contains the hip joints of diver  13 . A fin arm  20  is rigidly fixed perpendicular to swivel arm  18  in the plane of rotation of swivel arm  18  and rotates with swivel arm  18 . A stiff propulsive fin  21  lying in a plane perpendicular to the plane of rotation of swivel arm  18  and fin arm  20  is pivotably mounted to the rearward end of fin arm  20  by means of axle  22 . The axis of axle  22  lies in the plane containing the propulsion fin  21 . 
     Swivel arm  18  is made to measure about 12 to 16 inches from axle  19  to the outside end of swivel arm  18  so that the travel of its outside end is about 16 inches when fin arm  20  rotates from about 45 to 30 degrees on one side of connecting structure  16  to about 45 to 30 degrees on the other side of connecting structure  16 . Fin arm  20  is made as long as is consistent with transportation and other operational constraints so as to amplify the back and forth motion of fin  21 . The amplification of the back and forth motion of fin  21  both increases the lift force generated by fin  21  and aligns the lift force more closely with the direction of travel of device  12  and diver  13  thereby increasing the propulsive force component of the lift force. The present invention is most comfortably operated where the surface area of fin  22  is made so that the moment about axle  19  generated by the lift force on fin  21  is balanced by the moment exerted by the foot of diver  13  when diver  13  is pushing on a pedal  17  with one foot with a force about equal to the weight of diver  13  when diver  13  is pedaling at a rate of about one pedal stroke per second. This produces an exertion by diver  13  that is similar to the exertion experienced by climbing stairs at the rate of two stairs per second. Faster pedaling results in generation of greater lift force by fin  21  which, by the balance of moments about axle  19 , requires greater exertion by diver  13 . Slower pedaling results in generation of lesser lift force by fin  21  with consequent lessened exertion by diver  13 . 
     The reactive force that allows diver  13  to exert force on pedals  17  is transmitted through axle  19 , connecting structure  16 , and strut  14  to the hands and arms of diver  13 . When diver  13  is exerting a force about equal to his weight on a pedal  17  with one foot, the tensile force in each arm of diver  13  is about half of the weight of diver  13 . 
     The transmission for converting diver  13  pedaling motion into back and forth rotation of swivel arm  18  and fin arm  20  about axle  19  consists of pedal rods  24  extending rearward from pedals  17 . Pedal rods  24  are slidably fitted through holes  25  in a single strut, or as shown, dual struts  26 . Struts  26  are rigidly attached to connecting structure  16 . Tension lines  27  connect the rear ends of pedal rods  24  to the outside ends of swivel arm  18 . When diver  13  pushes one pedal rod  24  rearward by pushing reward the pedal  17  connected to it, the tension line  27  connected to the pedal rod  24  pulls the side of swivel arm  18  that is on the same side of connecting structure  16  rearward. The other end of swivel arm  18  pulls the tension line on the opposite side of connecting structure  16  forward, which also pulls forward the pedal rod  24  on the opposite side and the pedal  17  connected to it. 
     The length of tension lines  27  are adjusted for proper operation of device  12  as follows: Diver  13  stands on his toes, holds his arms straight down his sides and measures the distance L between the heels of his hands and the floor under his toes. Tension lines  27  are disconnected from pedal rods  24 . Fin arm  20  is rotated to one side of connecting structure  16  to the desired maximum angle between fin arm  20  and connecting structure  16 , about 30 to 45 degrees. Pedal  17  on the opposite side of connecting structure  16  from fin arm  20  and fin  21  is positioned to be distance L from the leading edge of strut  14 . The tension line  27  on the opposite side of connecting structure  16  from fin arm  20  and fin  21  is pulled taut and reconnected to its pedal rod  24 . The length D of this reconnected tension line  24  is measured. The length of the other tension line  27  is adjusted to D and it is reconnected to its pedal rod  24 . For divers of varying body dimensions, this adjustment procedure positions the leading edge of strut  14  rearward of the hip joints of diver  13  when device  12  is grasped by handholds  15  with the arms of diver  13  held straight down his sides. The adjustment procedure further causes fin arm  20  to reach its maximum angular extension with respect to connecting structure  16  when a leg and the connected foot of diver  13  is fully extended. 
     Propulsive fin  21  freely rotates about axle  22  to a maximum angle BETA on either side of fin arm  20 . Rotation to an angle greater than BETA is constrained by an attack angle controller  23  consisting of a length of line tethering the leading edge of fin  21  to fin arm  20 . The length of the attack angle controller  23  tether line is adjusted to constrain BETA. A spring may be inserted in series with the tether line. The length of the attack angle controller  23  tether line may be adjusted to adjust BETA to constrain the average angle of attack of fin  21  with respect to the flow of water past it. 
     Referring to FIGS. 4 and 5, a variation of the transmission for converting diver  13  pedaling motion into back and forth rotation of swivel arm  18  and fin arm  20  about axle  19  consists of replacing tension lines  27  and struts  26  with clamps  30  that are fixed to the outer ends of swivel arm  18 . Pedal rods  24  are inserted into clamps  30 . The distance S between the pedals  17  and clamps  30  is adjusted for proper operation of device  12  as follows: Distance L between the heels of hands of diver  13  and the floor under his toes is measured as previously described. The clamps grips  31  are loosened. Fin arm  20  is rotated to one side of connecting structure  16  to the desired maximum angle between fin arm  20  and connecting structure  16 , about 30 to 45 degrees. Pedal  17  on the opposite side of connecting structure  16  from fin arm  20  and fin  21  is positioned to be distance L from the leading edge of strut  14 . The clamp grip  31  on the opposite side of connecting structure  16  from fin arm  20  and fin  21  is tightened to securely grip its pedal rod  24 . The distance S along this reclamped pedal rod  24  is measured. The pedal  17  to clamp  30  length along the other pedal rod  24  is adjusted to S and the clamp grip  31  is securely tightened to grip its pedal rod  24 . For divers of varying body dimensions, this adjustment procedure positions the leading edge of strut  14  rearward of the hip joints of diver  13  when device  12  is grasped by handholds  15  with the arms of diver  13  held straight down his sides. The adjustment procedure further causes fin arm  20  to reach its maximum angular extension with respect to connecting structure  16  when a leg and foot of diver  13  is fully extended. 
     Device  12  is easily mounted and dismounted by diver  13  in the water. To mount device  12 , diver  13  simply grasps strut  14  with handholds  15  and applies his feet to pedals  17 . To dismount, diver  13  simply removes his feet from pedals  17  and releases his grip of strut  14 . 
     In addition to the roll followed by a pitch maneuver previously described, turns in the plane parallel to the surface of the body of water wherein the device  12  and diver  13  are located can be accomplished by more forcefully pushing the pedal  17  on the outside of the turn than the pedal  17  on the inside of the turn 
     The preferred embodiment of device  12  is to manufacture it from materials so that it is slightly positively buoyant. Weights can be affixed to device  12  to reduce or make negative its buoyancy to suit the purposes for which it is to be used. 
     Ventral  28  and/or dorsal  29  stabilizing fins lying in a plane perpendicular to the plane of rotation of the swivel arm  18  and fin arm  20  may be affixed to connecting structure  16  near axle  19  to resist sideways motion. 
     A variation of the embodiment of rigid connecting structure  16  together with any stabilizing fins  28  and/or  29  affixed to it consists of a free flooding hallow storage compartment with removable access panels for accessing the storage compartment. The storage compartment may be used by diver  13  to carry tools to an activity site which may include a tether for tethering device  12  near the activity site and/or swim fins to be used for better maneuverability of diver  13  when he has dismounted device  12 . 
     The preferred embodiment of fin  21 , axle  22  and attack angle controller  23  allows fin  21  to be detached from axle  22  and attack angle controller  23  and replaced by an alternatively sized and shaped fin. 
     Other variations in the details of construction for the device  12  are also possible. Thus, while the invention has been shown and described above with reference to a preferred embodiment, and a number of variations on the preferred embodiment have been discussed, it should be understood that what has been discussed above is for purposes of illustration only, and that the foregoing and other changes in form in detail may be made in the invention by one skilled in the art without departing from the spirit and scope of the invention which is to be defined only by the following claims.