Patent Publication Number: US-2011053443-A1

Title: System for Fin Placement on Surfboards

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 61/177,264 filed May 11, 2010, which is hereby expressly incorporated in its entirety by reference herein. 
    
    
     BACKGROUND 
     Ever since the advent of multi-fin design in surfboard manufacture there has been various fin configuration systems devised to capitalize on their respective advantages and disadvantages. 
     A very popular fin configuration known in the art as the thruster fin configuration consists of two widely spaced fins positioned approximately directly below the back foot of the surfer in his natural stance and very close to the edge or rail of the surfboard. A single trailing fin is positioned more towards the tail of the surfboard. The thruster fin configuration has made major breakthroughs in the maneuverability and control of surfboards due to its ability to complete fast turns and to grip the higher part of the wave. 
     A similar configuration using four rather than three fins is know in the art as the quad fin configuration. In this configuration there are two trailing fins rather than a single trailing fin. 
     The predominant configuration of the leading fins in any configuration is to place these fins close to the rail or edge of the surfboard. The intent is to use as much of the surfboards width as possible to allow the fins to be placed where they have the most likelihood of engaging the water during turns and during maneuvers at the high or steep parts of the wave. 
     This has resulted in a situation where it is common for the surfboard rider to have to move his foot in order to properly leverage and balance the forces acting on the surfboard and the fin during maneuvers. This repositioning of the foot results in momentary loss of control, the possibility of wrong placement and repositioning and also represents a significant delay in executing the turning maneuver. 
     There remains a need for a surfboard design that allows the surfer to make turns direction without the need relocate the foot. This way the surfer can keep their foot in the one location and execute turns and maneuvers faster and with more confidence. 
     SUMMARY 
     The following presents a simplified summary of one or more embodiments in order to provide a basic understanding of such embodiments. This summary is not an extensive overview of all contemplated embodiments, and is intended to neither identify key or critical elements of all embodiments nor delineate the scope of any or all embodiments. Its sole purpose is to present some concepts of one or more embodiments in a simplified form as a prelude to the more detailed description that is presented later. 
     In accordance with one or more embodiments and corresponding disclosure thereof, various aspects are described in connection with an improved surfboard design, as well as a system and method for fin placement on surfboards. In one embodiment, there is provided a surfboard having an elongated body that extends between a nose end and a tail end along a centerline of a longitudinal axis. The elongated body may comprise: a deck; a bottom surface; and a tail region. The surfboard may have a first fin securely mounted to the bottom surface in the tail region at a first lateral distance (e.g., a user defined distance) from the centerline, resulting in a first fulcrum of balance located along the first lateral distance. The deck may support a foot of a user placed in the tail region, the foot transferring a downward pressure to the body at a first pressure point (e.g., a point of pressure for a heel of the foot, or a point of pressure for a ball of the foot). Also, the first fulcrum of balance may be located between the centerline and the first pressure point, such that the user is able to apply the downward pressure to a fin-ward side of the first fulcrum of balance. 
     In related aspects, the first fulcrum of balance may occur at a location less than or equal to halfway from the centerline to the first fin. For example, the first fulcrum of balance may be located at about a midpoint of the first lateral distance. In further related aspects, the first fin may be mounted no greater than twice a first pressure point distance between the centerline to the first pressure point. 
     In yet further related aspects, a second fin may be securely mounted to the bottom surface in the tail region at a second lateral distance from the centerline, resulting in a second fulcrum of balance located along the second lateral distance. For example, the second fulcrum of balance may occur at a second location less than or equal to halfway from the centerline to the second fin. 
     In accordance with one or more embodiments and corresponding disclosure thereof, there is provided a surfboard comprising an elongated board having: a centerline of a longitudinal axis; a top surface; a bottom surface; and a tail region. The surfboard further comprises a first fin securely mounted to the bottom surface in the tail region at a first lateral distance from the centerline, resulting in a first fulcrum of balance located along the first lateral distance. The top surface may support a foot of a user placed in the tail region, the foot transferring a downward pressure to the board at a first pressure point. The first pressure point may be located between the first fulcrum of balance and the first fin, such that the user is able to apply the downward pressure to a fin-ward side of the first fulcrum of balance. 
     In accordance with one or more embodiments and corresponding disclosure thereof, there is provided a method that involves: (a) averaging a downward pressure by a user&#39;s heel in a tail region of a surfboard; (b) determining a pressure point in the tail region at which the heel transfers a defined downward pressure; and (c) mounting a fin to a bottom surface of the tail region of the surfboard at a selected distance from the surfboard&#39;s centerline, such that a resulting fulcrum of balance for the surfboard is located between the centerline and the pressure point. For example, the fulcrum of balance may occur at a location less than or equal to halfway from the centerline to the fin. 
     To the accomplishment of the foregoing and related ends, the one or more embodiments comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative aspects of the one or more embodiments. These aspects are indicative, however, of but a few of the various ways in which the principles of various embodiments may be employed and the described embodiments are intended to include all such aspects and their equivalents. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows an example embodiment in profile view from the rear. 
         FIG. 2  shows an example embodiment in plan view from the top. 
         FIG. 3  shows an example embodiment during turn while in the surf. 
         FIG. 4  shows a known type of fin placement method. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows an example embodiment that implements a thruster or tri-fin configuration looking from the back of the surfboard in profile view. The example embodiment relates to a turn executed by the surfer using downward pressure from the heel  15  in what is called a backhand turn in the art. The example embodiment can be assumed to use the same principles of design when applied to the toe and ball  22  of the foot or in a forehand turn as it is known in the art. 
     The figure depicts two leading fins in a thruster fin configuration namely the left  13  and right  12  fin. The surfer&#39;s rear foot  16  is depicted. The surfer applies downward pressure to the surfboard through the ball and toes  22  of his foot and through the heel  15  of his foot. Pressure is applied to either the heel or the ball and toes of the foot depending on whether the surfer wants to execute a forehand or ball and toes  22  based turn or a backhand or heel  15  based turn. 
     A point of balance  20  occurs at a location less than or equal to halfway between the distance  11  from the centerline  18  to the fin  12 . If the heel pressure  15  occurs at a distance  21  that is less than the distance  10  from the fulcrum point, the surfers downward pressure  15  will tend to force the surfboard to flatten out rather than to bank into the turn with a resulting loss of control and maneuverability. 
     However, if the heel pressure  15  is applied to a point that is a greater distance from the boards centerline  18  to the point of balance  20 , the result is that downward pressure  15  is applied directly to the fins  12  turning surface and the boards  14  bottom planning surface resulting in more control and a tighter turning circumference or arc. 
       FIG. 2  shows the example embodiment in plan view with the point of pressure for the heel  15  being applied at a distance  21  that is greater than the distance  10  of the point of balance  20  from the boards centerline  18 . 
       FIG. 3  shows the advantage of placing the fin  12  at a position defined by the design described herein. This figure further illustrates the forces that occur during the turn of a surfboard and how the design described herein produces advantages. 
     This figure illustrates a backhand turn where pressure is being applied to the surfboard by the heel  15  of the foot. The water surface  32  is being used by the surfboard for a plane effect. The curved shape of the surfboard is known in the art to contribute the boards ability to turn. As the board begins to turn, pressure  30  and the foiled shape of fins known in the art begin to add to the hydrodynamics allowing the board to turn. As the side of the surfboard  14  digs into the water  32  pressure starts to increase  31  at the side or rail of the surfboard. 
       FIG. 3  more readily illustrates how the placement of the fin  12  in the example embodiment is preferably no greater than twice the distance from the centerline  18  to the point of downward heel pressure  15  so that it  15  can be applied to the fin-ward side of the point of leverage  20 . 
     On this basis the equation for the placement of fins using this present design can be expressed as A&lt;2B, where A equals the distance of the fin  12  from the centerline  18  and B equals the distance from the centerline  18  to the heels point of downward pressure  15 . 
     Although the design described herein recognizes that this principle can be used to place fins at any distance less than twice the distance of the centerline  18  to the heel  15 , it is known in the art that there is a distinct advantage to placing the fins as far as possible apart to allow maximum opportunity for the fin  12  to engage and interact with the wave surface. 
     In the example embodiment the fin  12  placement is calculated to allow the complete point of contact between the heel and its applied downward pressure  15  and the surfboard deck to occur at a distance of greater than halfway between the centerline and the fin  12 . This will ensure that all applied force is made to the correct side of the fulcrum of balance  20  during the turn. 
       FIG. 4  is included as prior art for the purposes of clarification and explanation. This figure discloses one of the most used calculations for the placement of fins. In this calculation, the fins are placed approximately one inch  40  from the boards edge or rail. The intent is to ensure that there is maximum opportunity for the fin to engage and interact with the wave surface depending on the surfboards design. 
       FIG. 4  also exemplifies why there is a common need to reposition the foot during turns. If the distance from the centerline of the surfboard to the fin is more than twice the distance of the heel or toe-ball from the centerline of the board, the surfers downward pressure will be applied to the wrong side of the fulcrum of leverage forcing the board to move sideways away from the arc of the turn forcing a wider turn and possible loss of control. 
     With respect to alternative embodiments, even though the example embodiment uses a fin placement calculation that positions the complete heel region to the fin  12  side of the fulcrum of leverage  20 , an alternative embodiment can be applied to any fin  12  configuration that places the actual point of downward heel pressure  15  as a specific point located by averaging the downward pressure of the area covered by the heel as it makes contact with the board. It is noted that the design described herein can be used for surfboards with any number of fins greater than one. 
     The example embodiment discloses a method where the fins are attached to the surfboard using customized manufacture based on the intended user&#39;s foot length. Alternative embodiments could include a fin placement system to allow for multiple fin placements depending on the length of surfers foot. 
     An alternative embodiment could include a set of fin attachment devices known in the art set in multiple configurations to accommodate the longest, the middle and shortest average foot width of the intended customer population so that custom fin placement can be achieved without customizing the manufacturing process to each surfboard rider. 
     Alternatively, a customizable fin box system could be used that allows the fin to be placed anywhere in a range of positions depending on the foot length and in accordance with the rules set by the design of the embodiments described herein. 
     In accordance with aspects of the embodiments described herein,  FIG. 1  illustrates an exemplary surfboard that comprises an elongated board or body  14  extending between a nose end and a tail end along a centerline  18  of a longitudinal axis. The elongated body  15  may comprise: a deck; a bottom surface; and a tail region (see  FIG. 2 ). In one embodiment, a first fin  12  is securely mounted to the bottom surface in the tail region at a first lateral distance  11  from the centerline  18 , resulting in a first fulcrum of balance  20  located along the first lateral distance  11 . With reference to  FIG. 3 , the deck may support a foot of a user placed in the tail region, the foot transferring a downward pressure  15  to the body at a first pressure point (e.g., the tip of arrow  15 ). The first fulcrum of balance  20  may be located between the centerline  18  and the first pressure point, such that the user is able to apply the downward pressure  15  to a fin-ward side of the first fulcrum of balance  20 . In another embodiment, the downward pressure  15  may be at the ball or toe region of the foot. In yet another embodiment, the fin  13  is mounted to the bottom surface according to the principles described above with respect to fin  12 . 
     In related aspects, the first fulcrum of balance  20  may occur at a location less than or equal to halfway from the centerline  18  to the first fin  12 . For example, the first fulcrum of balance  20  may be located at about a midpoint of the first lateral distance  11 . In further related aspects, the first fin may be mounted no greater than twice a first pressure point distance  21  between the centerline  18  to the first pressure point (tip of arrow  15 ). 
     In the present example, the first lateral distance  11  comprises a user defined distance from the centerline  18 . In another example, (not shown), the first lateral distance may be defined with respect to the fin location or surfboard edge. In other words, the lateral distance may be defined as the distance from axis  19  toward the center of the board. 
     In yet further related aspects, the surfboard may comprise a second fin  13  securely mounted to the bottom surface in the tail region at a second lateral distance from the centerline  18 , resulting in a second fulcrum of balance located along the second lateral distance. Here, the foot may transfer a second downward pressure to the body at a second pressure point (e.g., at the ball and/or toes of the foot). The second fulcrum of balance may be located between the centerline  18  and the second pressure point, such that the user is able to apply the second downward pressure to a second fin-ward side of the second fulcrum of balance. For example, the second fulcrum of balance may occur at a second location less than or equal to halfway from the centerline to the second fin. 
     In still further related aspects, the first pressure point may be located between the first fulcrum of balance  20  and the first fin  12 , such that the user is able to apply the downward pressure to a fin-ward side of the first fulcrum of balance  20 . 
     In accordance with aspects of the embodiments described herein, there is provided a method that involves: (a) averaging a downward pressure by a user&#39;s heel in a tail region of a surfboard; (b) determining a pressure point in the tail region at which the heel transfers a defined downward pressure; and (c) mounting a fin to a bottom surface of the tail region of the surfboard at a selected distance from the surfboard&#39;s centerline, such that a resulting fulcrum of balance for the surfboard is located between the centerline and the pressure point. For example, the fulcrum of balance may occur at a location less than or equal to halfway from the centerline to the fin. 
     In the alternative, or in addition, step (a) may comprise averaging a downward pressure by a user&#39;s ball or toe area in a tail region of a surfboard, and step (b) may comprise determining a pressure point in the tail region at which the ball/toe transfers a defined downward pressure. The method may further involve performing similar calculations for a different part of the user&#39;s foot, and then mounting a second fin to the bottom surface of the tail region to achieve similar fulcrum-of-balance results as step (c). 
     While the present invention has been illustrated and described with particularity in terms of preferred embodiments, it should be understood that no limitation of the scope of the invention is intended thereby. Features of any of the foregoing methods and devices may be substituted or added into the others, as will be apparent to those of skill in the art. It should also be understood that variations of the particular embodiments described herein incorporating the principles of the present invention will occur to those of ordinary skill in the art and yet be within the scope of the invention.