Abstract:
A modular buoyant support apparatus is comprised of buoyant support modules of inflatable pontoons. The pontoons comprise inflatable cylindrical tubular chambers, typically fabricated of polymer coated fabric sheet material. Pontoons are fashioned so that they may be connected directly, in a modular fashion, to the underside of an appropriately configured dock platform. In some embodiments, a pontoon presents a relatively planar surface to the underside of the dock platform. The pontoons connect with attachment mechanisms depending from the dock platform via attachment points integral to or connected to the pontoons. Advantageously, the pontoons may be shipped deflated to the location for the dock and, in situ, both inflated for deployment and deflated for maintenance or relocation.

Description:
PRIORITY CLAIM 
       [0001]    This application claims priority from and is a continuing application of application Ser. No. 11/395,797 filed Mar. 31, 2006 whose content is fully incorporated herein. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to buoyant platforms which have provisions for berthing of boats thereto or thereon, as floating docks, and more specifically to improvements thereon as modular structures. 
       BACKGROUND OF THE INVENTION 
       [0003]    Among the many methods known and used for berthing of boats, floating docks are known to have particular advantages. Secured or anchored in some fashion, such docks can provide mooring for boats in areas which were formerly open water. Floating upon the body of water, such docks provide convenient mooring at a constant level above the surface, in contrast with fixed docks whose use may at times be rendered difficult or impractical due to varying seasonal depth of the body of water. Floating docks can provide mooring in bodies of water in which securing a fixed dock is difficult, as in deep muddy or sandy bottoms. Further, floating docks may serve many purposes other than mooring boats, such as serving as floating platforms for the convenience of swimmers, for example. Yet further, because they are not rigidly fixed in place, floating docks may be constructed in a modular manner that allows for easy adjustment of the dock surface area and configuration, often in the form of interconnecting rectangular modules, for example as described in U.S. Pat. No. 5,941,660 to Rueckert. Because of these many advantages, floating docks are widely used in conjunction with boating and other aquatic activities. However, floating dock technology has heretofore suffered from a number of shortcomings as well. 
         [0004]    First, because a commensurate volume of water must be displaced for the dock to float, the required dimensions for floating dock pontoons present significant manufacturing costs if rigid pontoons are employed. To provide even a minimal amount of buoyancy such as 1000 pounds, the pontoons must displace approximately 125 gallons of water, often requiring expensive tooling to produce rigid pontoons of such size. For example, the GalvaFoam Steel Floating Dock of ShoreMaster Corporation of Fergus Falls, Minn. employs high density polyethylene pontoons to provide buoyancy. Similarly, Rueckert&#39;s dock cited above provides buoyancy by large polyethylene articles that are created in a rotating mold, at considerable cost. Even if floating dock pontoons are manufactured sectionally as float drums, as described in U.S. Pat. No. 4,974,538 to Meriweather, manufacturing rigid pontoons of such large displacement entails considerable difficulty and cost. 
         [0005]    Second, shipment of large rigid pontoons to the site where the floating dock is to be assembled and deployed entails additional difficulty and cost. Even when the pontoons themselves may not be costly, such as the steel tanks employed in the dock described in U.S. Pat. No. 4,979,453 to Sloan et al., their size of necessity results in significant shipping costs. 
         [0006]    Third, assembly and disassembly of a floating dock, whether for installation, maintenance or relocation, is more complicated when large rigid pontoons are involved, because of the difficulty in maneuvering pontoons of larger dimensions. 
         [0007]    Floating docks have been described which do not employ large rigid pontoons. In U.S. Pat. No. 4,727,820 to Klaus, for example, inflatable rings are used to provide buoyancy. By providing buoyancy with inflatable articles, such floating docks overcome some of the limitations of the art employing rigid pontoons. However, heretofore docks with inflatable pontoons have not provided the flexibility of configuration found in prior art modular floating docks. 
         [0008]    In provisional U.S. patent application Ser. No. 60/660,287 filed on Mar. 10, 2005 by the inventor of the present invention, a modular dock is described that employs a rigid frame to give connectivity and integrity to buoyant support modules comprised of inflatable pontoons. While the floating dock described therein provides needed flexibility of configuration, a simpler modular design, without the need for rigid support frames, may be preferred. 
       SUMMARY OF THE INVENTION 
       [0009]    The present invention improves upon prior art floating docks by providing a modular buoyant support apparatus comprised of buoyant support modules of inflatable pontoons. The pontoons comprise inflatable cylindrical tubular chambers, typically fabricated of polymer coated fabric sheet material. Pontoons are fashioned so that they may be connected directly, in a modular fashion, to the underside of an appropriately configured dock platform. In some embodiments, a pontoon presents a relatively planar surface to the underside of the dock platform. The pontoons connect with attachment mechanisms depending from the dock platform via attachment points integral to or connected to the pontoons. Advantageously, the pontoons may be shipped deflated to the location for the dock and, in situ, both inflated for deployment and deflated for maintenance or relocation. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0010]    The foregoing objects, as well as further objects, advantages, features and characteristics of the present invention, in addition to methods of operation, function of related elements of structure, and the combination of parts and economies of manufacture, will become apparent upon consideration of the following description and claims with reference to the accompanying drawings, all of which form a part of this specification, wherein like reference numerals designate corresponding parts in the various figures, and wherein: 
           [0011]      FIG. 1  is an overhead view of an inflatable pontoon module according to the present invention; 
           [0012]      FIGS. 2   a  and  2   b  represent cross-section views along the main axis of two embodiments respectively of an inflatable pontoon module according to the present invention; 
           [0013]      FIG. 3  is a side view of a floating dock according to the present invention; 
           [0014]      FIG. 4  is a perspective view of a floating dock according to the present invention; and 
           [0015]      FIG. 5  is a cross-section of an alternative embodiment of an inflatable pontoon module according to the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0016]    Referring to  FIG. 1 , illustrated is a top view of an inflatable pontoon module according to the present invention. Pontoon  102  comprises a tube of polymer coated fabric material, with closed ends of the same or similar material, made airtight. Pontoon  102  is further fitted with valve  104  for inflation and deflation in the manner of inflatable rafts of rubberized fabric, well known to those in the art. In preferred embodiments, pontoon  102  comprises a plurality of chambered sections, so that in the event of a rupture, the pontoon will still retain partial buoyancy. 
         [0017]    Affixed to the side edges of pontoon  102  are a number of grommets  106  which will serve as attachment points for attaching pontoon  102  to a dock platform. Grommets  106  may be made of any relatively rigid and durable material, such as metal or plastic, suitable for prolonged use in a marine environment. In preferred embodiments, the area of pontoon  102  to which grommets  106  are affixed is strengthened, as further explained in reference to  FIG. 2  below, to reduce the likelihood of tearing of the pontoon at the grommets. 
         [0018]    Turning now to  FIG. 2   a,  illustrated is a cross-sectional view of an inflatable pontoon module according to the present invention. Pontoon  202  contains valves  204 ,  205 , illustrated here pressed into the body in a concave configuration employed to recess the valves when they are not needed for inflation and deflation, in a manner familiar to those of skill in the art. Valve  204  is located on the top surface of pontoon  202 . Valve  205 , located on the side of pontoon  202 , provides access for inflation and deflation at times that the pontoon is attached to a dock platform, when the abutment of the top side of pontoon  202  against the underside of the platform prevents access to any valve located on the upper surface of pontoon  202 . Grommets  206  pass through a portion  208  of pontoon  202 . In preferred embodiments, the tensile and shear strength of portion  208  of pontoon  202  is enhanced, by fabrication with additional fabric, additional rubberizer, or strength-enhancing material, such as fabrics reinforced with fiberglass, Teflon®, carbon fiber, and the like, a precaution understood by those of skill in the art to reduce the risk of tearing of inflatable fabric at a mechanical connection point such as grommet  206 . 
         [0019]    Persons of skill in the art will recognize that the present invention is not limited to inflatable pontoon modules of the particular configuration depicted in  FIG. 2   a.    FIG. 2   b  illustrates an alternative inflatable pontoon configuration in keeping with the spirit of the present invention. Just as in the embodiment illustrated in  FIG. 2   a,  pontoon module  202  comprises grommets  206  passing through a portion of module  202 . However, the pontoon module  202  in  FIG. 2   b  contains an inner retaining partition  210 , connecting the top and bottom surfaces of module  202 , thereby restraining inflation at the top and bottom surfaces of module  202 , resulting in a pontoon that is concave along its top and bottom surfaces when it is fully inflated. It will be appreciated, in light of this specification, that the present invention encompasses a very wide variety of pontoon configurations in addition to those depicted in the drawings. 
         [0020]    Turning now to  FIG. 3 , illustrated is an end view of a modular floating dock according to the present invention. Dock  301  is comprised of a plurality of inflatable pontoon modules  302  connected to substantially planar dock platform  304  by attachment means  306 . As depicted, attachment means  306  may comprise bolts of a material suitable for use in a marine environment, such as stainless steel or nylon, depending from platform  304  and passing through grommets (such as illustrated in  FIGS. 1 and 2 ) in pontoon modules  302 . Pontoon modules  302  may then be secured to the underside of platform  304  by retention with washers and nuts tightened on bolts  306 . 
         [0021]    Platform  304  may be constructed of various materials, but should preferably be relatively lightweight, rigid, and durable in a marine environment. Suitable materials include treated wood, fabricated sheet aluminum and durable plastic resin polymeric materials. 
         [0022]      FIG. 4  depicts a perspective view of a modular floating dock according to the present invention. Dock  401  comprises a plurality of inflatable pontoon modules  402  connected to substantially planar dock platform  404  by attachment means  406 . As depicted, means  406  may simply be heads of bolts retaining pontoon modules as discussed in reference to  FIG. 3  above. In any case, the utility of dock  401  may require that the surface of platform  404  be substantially without protuberances or depressions, in which case means  406  may be counter-sunk or provided with a suitably adapted cover to achieve such a result. 
         [0023]    While nut-and-bolt/grommet attachment means have been illustrated and described in reference to the attached drawings, it will be clear to those of skill in the art that many other ways of attaching the inflatable pontoons to the dock platform are possible in keeping with the spirit of the present invention. Indeed, as will be clear to those of skill in the art, the present invention is not limited by the particulars of the attachment means; rather, it is intended that the present invention encompass all means of attaching the inflatable pontoon modules to the deck platform. For example, attachment means may comprise an expansion or hinged “T” type anchor bolt, inserted through apertures in the deck and matching grommet holes in the pontoons, the anchor bolt then screwed from the topside of the platform to engage and retain the pontoon. In the alternative, hooks or lashing may be employed to secure pontoon modules  402  to platform  404 . 
         [0024]    Alternatively, the pontoon may be fashioned with a section adapted for mounting to a suitably adapted attachment means on the platform, as illustrated in  FIG. 5 .  FIG. 5  is an end view of a pontoon module according to an alternative embodiment of the present invention, wherein, integral to pontoon  502 , is a seamed mounting ridge  504 , serving as an attachment point for attachment means attached to the dock platform. Such attachment means may comprise a clamp depending from the underside of the platform, the clamp adapted to grasp pontoon  502  at seamed mounting ridge  504 . In the alternative, such attachment means may comprise a hook or other means of engagement of mounting ridge  504 . As will be clear to those of skill in the art, such an engagement means may advantageously be fashioned to retain mounting ridge  504  releasably, thereby enabling individual pontoon modules to be independently attached and released from the dock as needed, for maintenance, repair, replacement and the like. 
         [0025]    While the dock has been illustrated as a rectangular unit, it will be clear to those of skill in the art that the present invention is suitable for a wide range of dock configurations, owing to the modular nature of the inflatable pontoons. For example, “U”, “L” and “T” dock configurations are easily supported by the present invention. 
         [0026]    Furthermore, while the dock platform has been illustrated as a single, integral unit, it will be clear to those of skill in the art that the dock platform itself may be fashioned in modules, permitting modular construction of a wide variety of dock platform configurations adaptable for flotation by the inflatable pontoon modules. 
         [0027]    Although the detailed descriptions above contain many specifics, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of this invention. Various other embodiments and ramifications are possible within its scope, a number of which are discussed in general terms above. 
         [0028]    While the invention has been described with a certain degree of particularity, it should be recognized that elements thereof may be altered by persons skilled in the art without departing from the spirit and scope of the invention. Accordingly, the present invention is not intended to be limited to the specific forms set forth herein, but on the contrary, it is intended to cover such alternatives, modifications and equivalents as can be reasonably included within the scope of the invention. The claims appended hereto and made a part of this provisional patent application in no way limit the inventive matter specified herein; rather, the following claims are intended to be exemplary only, to clarify and illustrate certain embodiments of the present invention.