Patent Publication Number: US-6663452-B1

Title: Aquatic fins

Description:
BACKGROUND OF THE INVENTION 
     1. Field 
     This invention relates generally to fins worn by users of pontoon boats and float tubes and more particularly to such fins as permit the user to safely and easily mount and dismount from float tubes and pontoon boats and walk around the water&#39;s edge and into the shallow water over slippery underwater obstacles and maintaining his or her balance. Further such fins provide the user the ability to maneuver a pontoon boat or float tube with his or her feet. 
     2. State of the Art 
     In the past, swim fins have been modified in various respects in attempts to aid maneuvering of water craft. Such attempts to use swim fins, however modified incur the problem of having the same water resistance in opposed directions, thus swim fins are relatively useless in trying to propel pontoon boats or float tubes while the individual is in an upright position, like standing in some float tubes or sitting in some pontoon boats or float tubes with his or her feet and legs dangling in the water. Further problems exist regarding the possibility of falling while trying to maneuver in or out of a float tube or pontoon boat, which is in shallow water, in which the wearer could slip and fall and suffer potentially serious injury or even drown, especially if the individual is in a remote area far from help. 
     To overcome some of these difficulties, various devices have been conceived. One such arrangement is set forth in Celik&#39;s U.S. Pat. No. 6,077,139. The fins actions are like butterfly wings that close on forward striding on dry land or river bottom, yet in deep water, rearward movement of the foot or leg propel the float tube forward in the direction the user if facing. Maneuvering in this fashion causes the float tube to move towards the casting direction of the fisherman, more readily tangling his fishing line. 
     Other designs such as Johnson&#39;s U.S. Pat. No. 6,227,923 B1 disclose propulsion fins, which again move the user in the direction they are facing and the propulsion devices require mechanical unlatching when in use to propel the boat. They are designed such that the user can release the fin member with the toe of one foot cover engaging the latch on the rear of the other fin member. When walking in shallow water or on dry land, the user must make sure the fin member is securely latched. 
     Another such design fails to have a latching mechanism and thus the fin is like a half sole shoe in which the sole has come loose at the rear and remains attached at the toe. As the fisherman move his or her legs in the water the fin resists movement rearward to propel the float tube and fold against the shoe sole with forward movement. On dry land with little or no fluid resistance, the fin tends to flap when walking. See Schneider&#39;s U.S. Pat. No. 4,664,639. 
     The Johnson&#39;s U.S. Pat. 6,227,923 B1 reference discloses a number of other awkward arrangements for foot propulsion of float tubes or pontoon boats. It would be recognized that in the sitting position in pontoon boats and float tubes with the individual&#39;s feet dangling in the water without some means of lessening the water resistance in one direction is essential for properly maneuvering the craft in a forward and rearward direction. 
     Other fins currently on the market are generally too long, heavy, uncomfortable and make it difficult to enter or exit the water craft. Many of such fins are designed strictly for propulsion and make walking in shallow water and on shore difficult and somewhat awkward and likewise somewhat susceptible to slip and fall accidents. Obviously when fishing from a pontoon boat or a float tube, it is necessary to get to the craft, which is in the water, to get in or out of the water craft and to be able to standup and walk in the water without having to remove the fins. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide fins for propelling pontoon boats and float tubes, which permit the user to put on, safely walk on the shoreline into the water and get into the water craft wearing the fins, in which the blade section of the fins are angled upwardly in the forward direction to permit a reasonable walking stride for the individual without the fins causing the individual to stumble or trip. Thus permitting the wearer to readily traverse from the shoreline into the shallow water over underwater surfaces and enter the water craft with relative ease. 
     It is another object of the invention to provide a fin blade design, which provides the desired function to provide the maximum thrust by the upward movement or stroke of the legs and minimal resistance on the downward stroke. 
     It is still a further object of the invention to provide a spoon or shallow ladle design with its greatest breadth centrally or medially of the fin blade to provide maximum resistance or thrust on the upward movement of the spoon shaped fin and provide a minimum resistance on the downward movement, thus propelling the water craft forward with the person facing aft of the water craft. 
     It is a further feature of the fins to incorporate a sole with cleats or lugs around the periphery and a high density felt gripping pad between the cleats or lugs whereby the lugs allow the user to walk on rough and rocky surfaces and the felt reduces the risk of slipping while in or out of the water. Such arrangement provides better traction for standing and walking or wading on the bottom of a river or lake. The length of lugs and depth of the high density felt is tapered from the front to the rear to provide a more uniform and flat plane from the heel of the wearer&#39;s boot to the blade section of the fin, thus limiting any rocking motion. 
     It is still further a feature of the fin to provide quick release straps to secure the fin to an individual&#39;s foot or boot. A cross strap is provided with slot plates on each end, which seat over a roundish projection with a non-circular top and an adjustable heel strap with clips on each end oriented to seat over the non-circular top and rotate into position behind the wearer&#39;s heel and thus secure the cross strap and heel strap around the wearer&#39;s boot. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 side elevation view of the aquatic fin illustrating the upward angle of the fin. 
     FIG. 2 is a top view of the fin illustrating the blade arrangement and belt and heel band 
     FIG. 3 is a sectional view taken along lines  3 - 3  in FIG.  2 . 
     FIG. 4 is a bottom view illustrating the arrangement of the lugs and the gripping pad. 
     FIG. 5 illustrates in perspective, the relative positioning of the latch plate and locking buckle to the fin button. 
     FIG. 6 is a sectional view taken along lines  6 - 6  of FIG.  5 . 
     FIG. 7 shows a movement into the latching position. 
     FIG. 8 shows the relative rotation to lock the latching mechanism with the heel band in place. 
     FIG. 9 illustrates in perspective, the relative position of the latch plate and locking buckle when locked. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to FIGS. 1 through 4, the fisherman&#39;s fins generally referred to by  10  has blade section  2 , which is angled upwardly from the plane of sole  3 . Fin  10  has foot retaining section  5  integral to blade section  2 . Blade section  2  has a peripheral rib  7  on each side and two stabilizing ribs  8  as well as struts  12  (see FIG.  4 ), to aid in retaining blade section  2  with concavity  2   a  on the topside. The front edge  9  of blade section  2  is rippled. Referring, particularly to FIG. 4, blade section  2  has convexity  2   b . Side walls  11  and struts  12  aid in retaining the underside of blade section  2  with convexity  2   b . Side walls  11  and struts  12  join blade section  2  to foot retaining section  5  and also provide channels  13  for passage of water from convexity  2   b  through channels  13  to foot retaining section  5 . 
     When the user of fins  10  is seated with his or her legs in a vertical position or a horizontal position in a watercraft, fins  10  aid in propelling the craft. When the wearer moves his or her foot forwardly and upwardly, concavity  2   a  offers more resistance to the water than encountered by convexity  2   b  when the foot is moved downwardly and rearwardly. Concavity  2   a  on the top side of blade section  2 , together with peripheral rib  7  in conjunction with struts  12 , maintain the rigidity of concavity  2   a  and thus provides more propulsion force on the forwardly and upwardly movement of the wearer&#39;s foot. Likewise, on the downwardly and rearwardly movement of the wearer&#39;s foot convexity  2   b  on the underside of blade section  2  disburses the water around front edge  9 , peripheral ribs  7  and through channels  13  reducing the resistance of the water. Consequently, concavity  2   a  on the forward and upward movement of fin  10  through the water provides greater thrust than provided on the downward movement of fin  10  through the water due to convexity  2   b  and channels  13 . 
     Again referring to FIGS. 1 and 4, sole  3  has central fabric gripping pad  16  attached to the center of sole  3  and sole  3  has a series of peripheral arranged lugs  17 . Fabric gripping pad  16  may be secured to sole  3  with Velcro® fasteners with the loop members affixed to sole  3  and the pile section affixed to gripping pad  16  although either the pile or loops may be secured to sole  3 . It should be noted that the length of cleats or lugs  17  are tapered, in descending length towards the rear from blade section  2 , such that the individual wearing fin  10  would not have a tendency to rock standing on a flat, level surface. 
     Foot retaining section  5  has throat region  18 , which accommodates insertion of wearer&#39;s foot with varying size boots  19 . Each side wall  11  has button  21  having a roundish or cylindrical stem  22  integral with side walls  11  and generally radial tip or oval knob  23 . In order to retain fin  10  on wearer&#39;s boot  19 , belt  25  with free strap  25   a  and buckle strap  25   b  is placed over knob  23  and engages cylindrical section  22  by triangular shaped fastener or latch plate  27 , which has elongated opening or slot  28  that fits over knob  23  and seats about roundish stem. Buckle strap  25   b  is secured at one end to buckle  26  and at the other end to a triangular shaped fastener  27  by nylon webbing and free strap  25   a  is made of nylon webbing and also is secured to a triangular shaped fastener  27 . 
     Referring now in particular to FIGS. 5 through 9, heel strap  31 , which is preferably made of stretch rubber, has a pair of locking buckles  32 . Each locking buckle  32  has hollow interior  35  formed by side walls  36  and back wall  37  and face  38 . Face  38  has elongated slot  40 , which when properly oriented seats over radial tip or knob  23  and rotates about stem  22  with strap  31  positioned behind the wearer&#39;s foot or boot  19 . Due to hollow interior  35 , locking buckle  32  is free to rotate about stem  22  and thus position itself such that radial tip or knob  23  is crosswise to elongated slot  40 . Locking buckle  32  includes slots  41 , which accommodate the adjustment of heel straps  31  in slots  41 . 
     In order for the wearer to retain fin  10  on his or her foot or boot  19 , the wearer inserts his or her foot in foot retaining section  5  and hooks belt  25  with latch plates  28  positioned over button  21  on each side of fin  10  and then free strap  25   a  attached to adjustable buckle  26  may be adjusted to secure foot retaining section  5  across the wearer&#39;s foot or boot  19  expanding or contracting throat region  18 . Locking buckle  32  on heel band  31  is oriented to seat over knob  23  and rotated to position heel band  31  behind the heel of boot  19 . Strap  31  may be adjusted by shortening or lengthening one or both ends of heel band  31  in slots  41  of locking buckle  32 . Thus it can be seen by positioning latch plates  27  over button  21  and then positioning locking buckles  32  with heel bands  31  attached, oriented with and seated over knob  23 , locking buckles  32  can then be rotated to secure belt  25  and heel band  31  to fin  10  to prevent fin  10  from inadvertently coming loose form the wearer&#39;s foot or boot  19 . 
     Although the preferred embodiment of the invention has been disclosed, it will be appreciated that various modifications will be readily apparent to those skilled in the art, however, such changes and modifications are within the scope of the invention as defined in the appended claims.