Abstract:
A skateboard has a hard top skin formed with a top concave skin cavity. The hard top skin has an inside surface. The hard top skin is pervious to light. A top layer of adhesive adheres to the hard top skin. A flexible plywood core is formed with a top profile and a bottom profile. The top profile matches and receives the top hard skin. The top layer of adhesive adheres to a top surface of the plywood core. A bottom layer of adhesive adheres to a bottom surface of the flexible plywood core; and a hard bottom skin is formed with a bottom concave skin cavity. The bottom concave skin cavity is formed to fit to the bottom profile. The hard bottom skin is pervious to light.

Description:
[0001]    This application claims priority and is a continuation in part from inventor THOMPSON, Dean U.S. utility patent application Ser. No. 12/842,404 entitled Hard Shell Bodyboard Kickboard, filed Jul. 23, 2010, the disclosure of which is incorporated herein by reference. This application also claims priority from and is a continuation in part from inventor THOMPSON, Dean U.S. utility patent application Ser. No. 12/857,744 entitled PVC Shell Skatepark, filed Aug. 17, 2010, the disclosure of which is incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention is in the field of skateboards. 
       DISCUSSION OF RELATED ART 
       [0003]    Skateboards come from a family of sports boards. Since they are used for recreation, decoration is preferred. A variety of patents describe different configurations for applying printed film to a soft body board. A variety of sports boards have been treated with different constructions for maintaining a balance between cost and performance. Sports boards can be stiff, or have variable stiffness such as described in Moran U.S. Pat. No. 5,224,890 issued Jul. 6, 1993, entitled Bodyboard With Variable Stiffness the disclosure of which is incorporated herein by reference. Szabad in U.S. Pat. No. 4,850,913 describes a sports board having a slick film surface and a method for making, issued Jul. 25, 1989. Szabad teaches a sports board for surfing, snow sledding or other sports having a shaped polyethylene plywood core to which a polyethylene film and polyethylene plywood sheet laminate is heat laminated over substantially all the surfaces of the core 
         [0004]    Core stiffening has also been accomplished by using flexible plywood for the sports board core. Burke in U.S. Pat. No. 6,908,351 issued Jun. 21, 2005 entitled Flexible plywood core sports board, provides for an flexible plywood core sports board, the disclosure of which is incorporated herein by reference. The flexible plywood&#39;s core sports board has side rail skins and a slick skin on the bottom with a blend of flexible plywood and polyethylene on the top. Schneider in U.S. Pat. No. 5,211,593 provides a plywood core structure with graphics imprinted skin, issued May 18, 1993, the disclosure of which is incorporated herein by reference. Schneider discloses a multi-layer graphics imprinted skin laminated to a sports board. 
         [0005]    Pearson in U.S. Pat. No. 6,203,389 entitled bodyboard, issued Mar. 20, 2001 describes a bodyboard, “having a durable, slick outer skin on the lower surface, a conventional upper surface and a specially shaped lower surface for maximized speed, maneuverability, and performance”, learned disclosure of which is incorporated herein by reference. Pearson teaches a plywood core covered by bidirectional epoxy cloth, which has been popular in less expensive sports boards. Unfortunately, the epoxy cloth is usually not very durable. 
         [0006]    Yeh in U.S. Pat. No. 6,988,920 entitled Slider having improved resistance to erosion and wear, issued Jan. 24, 2006, describes a bodyboard that has a polyethylene plywood skin laminated to a polyethylene plywood board, the disclosure of which is incorporated herein by reference. Yeh teaches a soft outer film receiving graphic print and being bonded to the polyethylene plywood board with a plurality of concave depression formed on the top and side edges to enhance grip. A variety of different configurations have been tested in the water, in the marketplace, and described in the patent literature. While there has been much advancement in the area of high end performance body boards, there has been little improvement in improving less-expensive constructions. 
         [0007]    A variety of other graphic film have been applied to skateboard for laminate construction. For example, U.S. patent application 2008/0020166 published Jan. 24, 2008 by inventor Esposito, the disclosure of which is incorporated herein by reference, teaches and a decent antiskid material laminated along with a translucent filler grip piece. It has also been known to use grip tape, such as described in Fuster, U.S. Pat. No. 5,622,759 issued Apr. 22, 1997, the disclosure of which is incorporated herein by reference. Grip tape may include an abrasive material such as silicon carbide disposed on a tape. Laminate graphic print can also be seen in Parten U.S. Pat. No. 4,921,513, entitled Method Of Manufacturing A Skateboard issued May1, 1990, the disclosure of which is incorporated herein by reference. Parten describes that a preprinted label applied to a board lower surface can be sealed by applying a suitable coating to protect the label. 
       SUMMARY OF THE INVENTION 
       [0008]    A skateboard is generally planar configuration and has a deck that has a pair of upturned ends, namely a front upturned end and a rear upturned end. A plurality of wheels are mounted to a bottom of the skateboard. The plurality of wheels includes at least a front wheel and at least a rear wheel. A plywood core formed as a plank is formed with a top profile and a bottom profile. The top layer of adhesive adheres to a top surface of the plywood core. A top layer of adhesive is adhering to a top surface of the plywood core. A top hard skin can be matching and fitting to the top profile. The top hard skin has an abrasive layer providing traction for user on an outside top surface. The top hard skin has a top paint layer in printed on an underside of the top hard skin. The top hard skin is pervious to light. The top layer of adhesive adheres the top hard skin to the plywood core. A bottom layer of adhesive adheres to a bottom surface of the plywood core. A hard bottom skin is formed to fit to the bottom profile. The hard bottom skin is pervious to light and between 0.05 mm and 0.5 mm thickness PVC and made of PVC. 
         [0009]    The skateboard hard top skin, flexible plywood core, and hard bottom skin can be formed with a bottom convex. The hard top skin has a top printing means, and the hard bottom skin further has a bottom printing means. The top printing means has a graphic film a foil layer laminated to a graphic print layer, and the graphic print layer is laminated to the hard top skin. The hard top skin further has a top printing means which can be painting a lower surface of the hard top skin. The top hard skin can be transparent. The abrasive layer can also be transparent and made of a clear sand layer. 
         [0010]    Optionally, the hard top skin may have a top printing means, and the hard bottom skin may have a bottom printing means so that the bottom printing means includes a multi-layer graphic film comprising a foil layer laminated to a graphic print layer. The graphic print layer can be laminated to a top surface of the hard bottom skin. The bottom printing means may have the technique of painting an upper surface of the hard top skin. The printing means may include the hard top skin being made of PVC, and the hard bottom skin being made of PVC. The flexible plywood core is made of a flexible plywood plank formed with a bottom convex. The hard top skin, flexible plywood core, and hard bottom skin can be formed with a bottom convex. The top printing means may include a graphic film a foil layer laminated to a graphic print layer, such that the graphic print layer is laminated to the hard top skin. The top printing means may include painting a lower surface of the hard top skin with a contrasting color scheme. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a perspective view of the present invention. 
           [0012]      FIG. 2  is a close-up cross-section diagram of the layer construction. 
           [0013]      FIG. 3  is an exploded view diagram of the layer construction. 
           [0014]      FIG. 4  is a cross-section diagram of the hard sheet introduced into the mold. 
           [0015]      FIG. 5  is a cross-section diagram of the hard skin been removed from the mold. 
       
    
    
       [0016]    The following call out list of elements can be useful in referencing the element numbers of the drawings.
     11  Top Outside Graphic Layer     12  Top Hard Layer     14  Top Paint Layer     15  Top Skin     16  Top 1st Graphic Layer     17  Top 2nd Graphic Layer     18  Top Glue Layer     19  Top Substrate     21  Bottom Outside Graphic Layer     22  Bottom Hard Layer     24  Bottom Paint Layer     25  Bottom Skin     26  Bottom 2nd Graphic Layer     27  Bottom 1st Graphic Layer     28  Bottom Glue Layer     29  Bottom Substrate     41  Sheet Of PVC     42  Sheet Edge     43  Skin Cavity     45  Mold Cavity     46  Mold     47  Mold Top Face     48  Mold Top Edge   
 
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0040]    A skateboard is not perfectly flat and is curved, such as at the tips so that a user may more easily use the skateboard. The skateboard is curved in the longitudinal direction lengthwise and also widthwise having a shallow depression in the middle of the board. 
         [0041]    The present invention skate board is made in three basic parts, the top skin  15  is formed as a top cover that is preferably a hard skin of PVC which can be flexible. The bottom skin  25  is formed as a bottom cover which is also preferably a hard skin of PVC which can be flexible. The middle portion is a relatively flexible plywood core which can be formed as a pair of layers, namely a top substrate and a bottom substrate. It is preferred that the hard layer is preformed to shape, but can also be a flat. The top cover can be molded to a relatively hard skin shape, then the bottom cover can be molded to a relatively hard skin shape, and the top cover is fitted over a plywood core. It is preferred to make a batch of top covers, then make a batch of bottom covers and then making a batch of plywood cores that match the top and bottom covers. The final step involves assembly using a spray or film glue to glue the top and bottom covers to the plywood core. The preferred glue is a spray on glue. 
         [0042]    The top layer or top skin has a top hard layer  12  providing structural flexibleity and structural strength to the top skin  15 . The top hard layer  12  is preferably a sheet of transparent or translucent PVC that can be formed into a skin structure by vacuum forming in a hollow formation cavity. Depending upon the final shape, the top hard layer  12  can be made flexible with as thin as 0.01 mil thickness PVC, but can also be about 10 mil thick PVC if necessary, such as if the plank shape is relatively flat. It is preferred that the thickness is approximately between 0.05 mm and 0.5 mm thickness PVC. 
         [0043]    A hollow formation cavity of a mold cavity  45  can receive a rectangular sheet of PVC  41  having a sheet edge  42  around the edge of the sheet. The mold cavity  45  is an opening which receives a heated piece of transparent PVC and vacuum forms the sheet into a skin such as a top skin  15  having a skin cavity  43 . The skin cavity is concave. The top mold face  47  surrounds the mold cavity  45 . An edge of the mold, namely the mold top edge  48  defines the extent of the suction power. Suction is formed in the mold cavity  45  by a plurality of openings on the surface of the mold cavity  45 . 
         [0044]    The sheet of PVC  41  is preferably first laminated to other sheets, and then trimmed with a trimming machine so that sheet edges  42  are formed. The sheet of PVC  41  is then heated until it is soft enough to be vacuum formed in a mold cavity  45  of a mold  46  so that the hard sheet is bent to form a skin cavity  43 . The mold top face  47  is preferably flat so as to form a vacuum along eight mold top edge  48  four sucking in the hard sheet  41 . 
         [0045]    Before placing into the mold machine, the top hard layer  12  receives a top paint layer  14  on an underside of the top hard layer  12 . Also before placing into the mold machine, the top hard layer  12  optionally receives a top first graphic layer  16  or a top second graphic layer. Printing means may include a means for adding graphics to the top skin which is the hardtop layer. For example, the top first graphic layer can be a foil such as a metallized plastic sheet that is laminated to the top paint layer  14 , and the top second graphic layer can be a sheet of plastic film. Alternatively, the top first graphic layer can be a graphic film and at least some portions of the top paint layer  14  can be omitted so that the graphic film can be seen through the clear top hard layer  12 . Alternatively, the top skin can be directly screenprinted with a foil as the first or second graphic layer under the screen printing. Foil means metallic colored film which may have thin metal deposit, not a thick sheet of metal like standard kitchen use aluminum foil. 
         [0046]    After assembly, the top outside surface may receive a top outside graphic layer  11  which can be applied to the outside surface of the top hard layer  12 . The top outside graphic layer  11  can be formed as an adhesive sticker, or as a thermally laminated plastic sheet that adheres to the top hard layer  12 . The overlap channel  31  includes the elements of the laminate construction including the top paint layer  14  which is bonded to a top first graphic layer  16 , a top second graphic layer  17  and glued by a top glue layer  18  to a top substrate  19 . The glue layer  18  can be applied by a plastic adhesive film or by spray glue. It is preferred to use a spray glue  18 . Along the overlap portion, the spray glue  18  either: adheres the outside surface of the top hard layer  12  to the inside surface of the modern glue layer  28 ; or adheres the outside surface of the bottom hard layer  22  to the inside surface of the top glue layer  18 . 
         [0047]    The construction of the bottom layer is substantially similar to the construction of the top layer. The bottom layer has a bottom outside graphic layer  21  overlying a bottom hard layer  22 , which in turn receives a bottom paint layer  24 , and a bottom second graphic layer  26  and a bottom first graphic layer  27  which is secured by a bottom glue layer  28  to a bottom substrate  29 . A top substrate  19  can be connected to the bottom substrate  29  especially if the substrate is made of similar material so that the core can be a multiple layer core. 
         [0048]    The best mode for manufacturing the board is according to the following steps. The first step is to print the inside surface of the hard skin. The second step is to use laser printing for printing film which is heat laminated to the inside surface of the hard skin. The third step is to form the hard skin. The fourth step is to trim the hard skin edge in a trimmer. The fifth step is to spray glue on the inside of the hard skin. 
         [0049]    The best mode also includes the step of either painting the inside surface of the hard skin, or laminating printed film to the inside surface of the hard skin. Depending upon the design, it is generally more feasible to only paint the inside surface of the hard skin or only laminating printed film to the inside surface of the hard skin. The printed film can be printed on the inside surface of the printed film in reverse, or on the outside surface of the printed film in a positively printed non-inverted manner. The best mode is to print the film in a positively printed manner such that the print is on the top surface or outside of the printed film. The printing on the outside surface of the printed film would mean that the PVC and the printed portion may be touching. 
         [0050]    The printing on the printed film can be opaque or a shiny lucent paint. The best mode for printing means is to print on the outside surface of a foil sheet which is then laminated to the PVC. It is also possible to use a bilayer printed film construction by having print on the inside surface of a clear sheet which then receives a foil sheet underneath the clear sheet. The bi-layer printed film construction can be first printed in a roll and laminated together in a roll of printed film, for later lamination to a PVC sheet. Another manner of printing would be to print on the inside surface of the PVC sheet, and laminate a foil underneath the PVC sheet. 
         [0051]    It is preferred to add an abrasive layer on top of the top hard layer  12 . The abrasive layer can be a sanded finish with the graphic underneath the sanded finish. The top abrasive layer can be finished according to the prior art described such as in Parten U.S. Pat. No. 4,921,513. With a sanded finish, the sanded is adhered to the top hard layer  12  and the top outside graphic layer  11  is omitted. The top hard layer  12  is preferably screenprinted on an underside or backed with a top first graphic layer  16 . The abrasive layer provides a grip for the user. 
         [0052]    On the under side of the skateboard, the bottom hard layer does not receive a sanded finish and is preferably not abrasive in nature. 
         [0053]    Therefore, while the presently preferred forms of the invention been shown and described, and several modifications thereof discussed, persons skilled in this art will readily appreciate that various additional changes and modifications may be made without departing from the spirit of the invention, as defined and differentiated by the following claims.