Abstract:
A reinforced skateboard deck providing a rupture resistant region and a protective region to inhibit degradation of the rupture resistant region during use is disclosed herein.

Description:
This is a continuation application of U.S. Ser. No. 13/342,799, now U.S. Pat. No. 8,419,026, filed on Jan. 3, 2012, which is a continuation of U.S. Ser. No. 12/830,298, now U.S. Pat. No. 8,087,681, filed on Jul. 3, 2010, which is a continuation of U.S. Ser. No. 11/940,233, now U.S. Pat. No. 7,748,725, filed on Nov. 14, 2007, all of which are entitled Reinforced Skateboard Deck and hereby incorporated by reference in their entireties. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to the field of skateboard decks, and more specifically, to skateboard decks incorporating destructive force resistant materials. 
     2. Background 
     Skateboards are typically used today to ride up, over, and off of ramps and other structures, and the skateboard deck undergoes considerable stress when the rider and skateboard return to the ground. Skateboard decks have been strengthened by a laminated structure typically a seven-ply hardwood with the grain direction of the plies varied to provide strengthening in more than one direction. Such laminate decks are still subject to failure under significant impacts during typical skateboarding use. It is believed that a common failure of the laminate deck occurs where the top layer of the laminate will fail in tension when loaded, then the second sub-layer below that will in turn fail in tension, and then the next and next, working from the top of the deck to the bottom surface. 
     Skateboard decks have also been provided with fiber reinforcement, typically a fiberglass and resin matrix such as epoxy or other thermosetting resin. Fiber reinforced skateboards are known in the art, with some designs placing the fiber reinforcement between the hardwood veneer layers, while other designs have the fiber on the bottom or top major surface of the skateboard. It is believed that the location where a fiber reinforcement has the greatest effect in strengthening against common failure-inducing loads is the top major surface of the skateboard. When fiber reinforcement is placed in such a way as to be firmly and permanently adhered to the top major surface of the skateboard, the common failure mode is prevented from initiating. This is believed to be because the tensile load is distributed over not only the laminate structure of hardwood veneers, but also by augmenting the strength of the laminate structure by the fiber and resin matrix reinforcement. Propagation of rupture of the laminated hardwood veneers is believed to be reduced, because the fibers are both adding stiffness to the structure, and adding overall tensile strength to the skateboard. 
     Providing a layer of fiber reinforcement over the entire major surfaces of the skateboard deck has practical drawbacks given the common nature of use of skateboards where the edges of the deck are worn away by contact with the ground. The result of such contact and wearing away is that fibers are exposed at the edge of the deck. These exposed fibers, particularly in the case of glass or carbon fiber can be rigid and sharp. In the case of other fibers, such as aramid, or para-aramids or other engineering thermoplastic fibers, the exposed fibers are typically soft and pliable, but in any case create a cosmetically unattractive edge. 
     Therefore, what is needed and heretofore unavailable is a reinforced skateboard deck constructed to resist destructive forces typically occurring during use while protecting the reinforcing elements from wear and tear. 
     SUMMARY OF THE INVENTION 
     In accordance with a preferred embodiment constructed in accordance with the principles of the present invention, a multi-layer board with an intermediate section having a pair of opposing lateral edge sidewalls between a tail section and a nose section and an undersurface constructed to receive at least one set of trucks may include a rupture resistant layer extending at least partially through the intermediate section with a first region and a second region of the rupture resistant layer cooperating to form at least a portion of a dual density, exposed, foot bearing surface, with the first region including a fiber-reinforced material having a pair of outermost lateral edges spaced interior to the opposing lateral edge sidewalls of the intermediate section to form a recess at least partially occupied by the second region to define a first region protective barrier to prevent wear of the first region when the board slides along at least one of the opposing lateral edge sidewalls in use. 
     In another aspect of the present invention, the reinforced region includes a spacer layer. 
     In yet another aspect of the present invention, the reinforced region and the protective side barrier form complementary portions of the exposed foot bearing surface. 
     Methods for constructing a reinforced skateboard deck are disclosed as well. 
     Other aspects of the present invention will become apparent with further reference to the following drawings and detailed description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of the layers of a skateboard deck in accordance with an embodiment of the present description, showing an upper layer formed of a fiber-reinforced layer inlaid within a veneer, and six additional layers, with varying strand orientations, prepared for assembly; 
         FIG. 2  is a top plan view of the veneer for the upper layer prior to an initial cutting, showing a typical dimension; 
         FIG. 3  is a top plan view of the veneer of  FIG. 2  with a central portion removed to provide a side barrier defining a central opening; 
         FIG. 4  is a top plan view of the fiber-reinforced layer for the upper layer, showing a typical dimension, prior to an initial cutting; 
         FIG. 5  is a top plan view of the fiber-reinforced layer, after cutting to a typical shape, to fit the layer into the central opening of the side barrier; 
         FIG. 6  is a top plan view of the fiber-reinforced layer and the side barrier assembled to provide the upper layer; 
         FIG. 7  is a perspective view of a removable adhesive tape being applied to the fiber-reinforced layer and the side barrier to hold them together; 
         FIG. 8  is an end elevation view of the layers arranged together, including a spacer layer beneath the fiber-reinforced layer, showing a typical dimension; 
         FIG. 9  is an end elevation view of a mold pressing the layers together to form a blank skateboard deck which may subsequently be cut to a desired size and shape; and 
         FIG. 10  is a perspective view of a skateboard deck press molded to provide a raised nose and tail and cut to a final desired shape. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     As shown in  FIG. 1 , a skateboard deck, indicated generally at  10 , is typically formed of a series of wood veneer layers  12 , which are stacked and assembled together. Alternatively, other suitable materials, such as thermoplastics, and non-layered constructions may be used. 
     An upper layer  14  provides a top surface  16  and a bottom surface  18 . The top surface is typically the top structural (riding or foot bearing) surface of the skateboard deck, although a grip tape or other similar layer may be applied over the top surface. Upper layer  14  includes an inlaid, fiber-reinforced layer  20  that provides a portion of top surface  16 . 
     Fiber-reinforced layer  20  is typically formed substantially of woven para-aramid fibers. The fiber-reinforced layer may be made with unidirectional or bi-directional para-aramid fibers loosely woven into a fabric. As an example, layer  20  may include Kevlar® RTM (resin transfer molded) fabric encased in an adhesive matrix. As an example, the Kevlar® fabric may be substantially saturated with polyurethane, which is then allowed to harden before further processing. Other components of the adhesive matrix would include a resin of epoxy or polyvinyl. 
     Fiber-reinforced layer  20  defines an edge  22  (see also  FIG. 5 ), and typically has an oval or racetrack shape, although other shapes may be used as desirable for a particular skateboard design. 
     Upper layer  14  typically includes a side barrier  24  that also provides a portion of top surface  16 . Preferably, the side barrier and the fiber-reinforced layer together provide the entire top surface but alternatively other structure may provide a part of the top surface. Also preferably, the side barrier extends around the entire edge of the fiber-reinforced layer. Alternatively, the side barrier extends around only a portion of the edge of the fiber-reinforced layer, in which case some other structure may run alongside a portion of the fiber-reinforced layer or no structure as suitable to the desired skateboard design. The side barrier is typically a wood veneer, and as such includes the fibrous material that is naturally found in wood, however, the side barrier typically does not include any fiber reinforcement such as to leave behind a fringe or sharp edge of fibers as may be the case with Kevlar® or glass or carbon fibers. Alternatively, side barrier  24  may be formed from a thermoplastic sheet. 
     As best seen in  FIGS. 2 and 3 , side barrier  24  is made by starting with a wood veneer blank  26  from which a central portion  28  is removed to provide a central opening  30 , typically in an oval or racetrack shape, but alternatively with any shape suited to the specific skateboard. Thus, central opening  30  is defined by side barrier  24 . 
     As best seen in  FIGS. 4 and 5 , fiber-reinforced layer  20  is made by starting with a sheet of woven Kevlar® fabric  32  encased in an adhesive matrix, such as by substantial saturation with polyurethane. Sheet  32  is cut into an oval racetrack, or other suitable shape to produce layer  20 , which is preferably closely fitted for central opening  30  of side barrier  24  (see  FIG. 6 ). 
     Side barrier  24  and fiber-reinforced layer  20  are preferably die cut from blank  26  and sheet  32 , respectively, but any suitable means may be used. With die-cutting, the same press and die may be used to cut both the blank and the sheet. Side barrier  24  and fiber-reinforced layer  20  are typically of equal thickness although some variation is permitted. Alternatively, the fiber-reinforced layer may be substantially thinner, with the difference made up by a spacer layer  34  (see  FIGS. 8 and 9 ), typically of the same shape, such as oval, as fiber-reinforced layer  20 . Spacer layer  34  may be affixed, e.g., by adhesive, to the bottom surface of fiber-reinforced layer  20 , and may be cut to shape either separately or together with the fiber-reinforced layer. 
     As shown in  FIGS. 6 and 7 , after fiber-reinforced layer  20  and side barrier  24  are combined by placing layer  20  within central opening  30 , they may be temporarily held together by application of an adhesive tape  36 , e.g., the Peel A Play tape made by the R Tape Corporation of New Jersey. Adhesive tape  36  may be applied by a heat transfer press. 
     As best seen in  FIGS. 1 ,  8 , and  9 , skateboard deck  10  may include a first lower layer  38 , typically a wood veneer, defining an upper surface  40  and a lower surface  42 . Upper layer  14 , comprising side barrier  24  and fiber-reinforced layer  20 , is affixed, typically by application of adhesive and subsequent press molding at suitable heat and temperature, to first lower layer  38 . Additional lower layers may be included as desired in consideration of desired weight and strength factors. For example, second, third, fourth, fifth, sixth, and seventh lower layers  44 , with ultimate bottom surface  46 , may be affixed successively beneath the first lower layer, typically by application of adhesive and subsequent press molding at suitable heat and temperature. 
     Typically the lower layers are wood or other structural material with a strand orientation that is varied from layer to layer. As an example, with seven lower layers, two may be oriented to provide maximum cross board strength, while the remaining five maximize along board strength, although this scheme will be varied as appropriate for the desired performance characteristics. 
       FIGS. 1 ,  8 , and,  9  also illustrate that fiber-reinforced layer  20  is inlaid within side barrier  14 , and side barrier  14  preferably surrounds substantially all of edge  22  of fiber-reinforced layer  20 . As shown in  FIG. 10 , skateboard deck  10  may be press-molded to provide a raised tail  48  and a raised nose  50  and cut to a final desired shape. Furthermore, deck  10  may be drilled for truck mounting holes, and then trucks, bearing and wheels may be mounted to provide a skateboard ready for riding. A grip tape or other suitable tape, stickers or the like may be affixed over the top surface. Preferably the upper surface of fiber-reinforced layer  20  and the upper surface of side barrier  24  are flush with one another, presenting a smooth transition with no visible step. 
     Alternatively, upper layer  14  may be formed substantially of an adhesive matrix including a central portion of woven fiber encased therein to provide the fiber-reinforced layer. In this embodiment, the adhesive matrix includes an outer portion without woven fiber to provide the side barrier. 
     As described herein, skateboard deck  10  includes a top (or foot bearing) surface  16  for the rider&#39;s feet, and a bottom surface  46  for the connection of trucks and wheels. The top surface is provided in part by a fiber-reinforced layer  20 . The top surface is further provided by a side barrier  24  extending around at least a portion of the fiber-reinforced layer. 
     Typical thicknesses for the fiber-reinforced layer after saturation with polyurethanes are between about 0.010 to about 0.050-inches. Typical thicknesses for side barrier  14  are between about 0.040 to about 0.065-inches. The thickness of spacer layer  34  typically is adjusted to the appropriate thickness to accommodate the difference between fiber-reinforced layer  20  and side barrier  24  and provide a flush top surface  16 . As an example, where side barrier  14  is 0.060-inches thick, and fiber-reinforced layer  20  is 0.020-includes thick, spacer layer  14  is preferably 0.040-inches in thickness. All of these dimensions may be varied within and beyond these ranges as suited to the particular skateboard design. 
     Side barrier  14  may have varying width dimensions relative to skateboard deck  10  and fiber-reinforced layer  20 . The dimensions of the side barrier may be substantially uniform around the edge of the skateboard, or they may vary significantly as desired for specific skateboard characteristics. For example, the side barrier may be narrower along the sides as compared to the nose and tail. Side barrier  14  preferably has a minimum width of 0.125-inches along each long side of the skateboard. Side barrier  14  preferably has a width dimension between about 0.125-inches and about 6-inches adjacent the nose and tail of the skateboard. All of these dimensions may, be varied within and beyond these ranges as suited to the particular skateboard design. With this design, fiber-reinforced layer  20  is inset away from the edge of the skateboard, so that the fibers are shielded from contact when the skateboard edges are scraped on the ground or other surface. Fiber-reinforced layer  20  is preferably inlaid on top surface  16  of deck  10 , and additionally or alternatively may be inlaid on lower surface  42 . 
     It will be appreciated that the incorporation of the fiber-reinforced layer  20  and/or the fiber-reinforced layer as bonded to another layer of the deck assists in significantly resisting tensile forces commonly associated with use and improves the overall rupture resistance of the deck. When used at or near the top layer as a part thereof, the effectiveness of this rupture resistance feature increases. 
     While the present invention has been described herein in terms of a number of preferred embodiments for skateboard decks, various changes and improvements may also be made to the invention without departing from the scope thereof. The subject matter described herein includes all novel and non-obvious combinations and subcombinations of the various elements, features, functions and/or properties disclosed herein. Similarly, where the claims recite “a” or “a first” element or the equivalent thereof, such claims should be understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements.