Abstract:
A skate park system comprises interlocking pieces enabling quick assembly and disassembly. The disassembled pieces can lay flat, enabling storage in minimal space. Ramp, funbox and grindrail portions may be used separately or combined in varying manners to provide a variety of configurations.

Description:
BACKGROUND OF THE INVENTION 
   This invention relates to skates, bikes and skateboarding, and more particularly to a knockdown skateboard park-like ramp system. 
   Skateboarders, bikers and skaters enjoy performing jumps and stunts. To that end, many communities are building skateboard parks, with formed ramps, bowls and jumps. However, children learning to do skate, skateboard or bike riding, or those trying to improve their skills, either are intimidated at the skate park by other more skilled children, or don&#39;t have access to a park. 
   To overcome this, some have built home ramps or jumps. However, these home-built ramps are bulky, and consume a large amount of space when not in use, in a garage, for example. Parents often are unhappy with or have to deal with huge, unsightly structures in the yard or garage. Typically these structures are screwed together wooden assemblies which are very heavy, cannot be easily transported, are unsightly, aren&#39;t weatherproof, somewhat dangerous due to splinters/loose screws, and can&#39;t be easily stored in a home environment. 
   SUMMARY OF THE INVENTION 
   In accordance with the invention, a knockdown system is provided wherein a skate, bike or skateboard, ramp is easily assembled for use, in different configurations, but quickly breaks down without tools and stores nearly flat. 
   Accordingly, it is an object of the present invention to provide an improved skateboard park system that stores flat. 
   It is a further object of the present invention to provide an improved skateboard park system that is easily assembled. 
   It is yet another object of the present invention to provide an improved skateboard park system comprising a “funbox”, grind rail, and ramps. 
   It is yet another object of the present invention to provide an improved skateboard park system that is easily assembled to build quarter pipes, more elaborate rails, pyramids, etc. 
   The subject matter of the present invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. However, both the organization and method of operation, together with further advantages and objects thereof, may best be understood by reference to the following description taken in connection with accompanying drawings wherein like reference characters refer to like elements. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective wire frame view of an embodiment of the invention in an assembled form; 
       FIG. 2  is a perspective view of a close up of the attachment hook; 
       FIG. 3  is a perspective view illustrating insertion of the hook into the slot; 
       FIG. 4  is a perspective view as in  FIG. 3  with the hook fully engaged into the slot; 
       FIG. 5  is a view illustrating building up the “funbox”, wherein the particular configuration is 4 sides and one center brace, with the center brace not yet installed; 
       FIG. 6  is a view showing that the top of the “funbox” is two panels in the illustrated embodiment wherein the top pieces interlock slots in the box to make it rigid and to hold it square and wherein ramps may be plugged into any side of the box; 
       FIG. 7  is a view showing a ramp is being attached to the box; 
       FIG. 8  is a view showing the two ramp top pieces being laid in place and that they interlock into corresponding slots; 
       FIG. 9  is a view showing a ramp attached to a “funbox”; 
       FIG. 10  is a view showing a skateboarder using a box with one ramp; 
       FIG. 11  is a view illustrating building up a ramp to use by itself, wherein a ramp with “funbox” is visible in the background; 
       FIG. 12  is a view showing using the ramp by itself as a “launch ramp”; 
       FIG. 13  is a view showing attachment of a “grind rail” to the fun box; 
       FIG. 14  is a perspective view of two ramps attached to a “funbox” with a “grind rail”; 
       FIG. 15  is a view of a skateboarder “board sliding” the “grind rail” as an example of one of the uses of the invention; 
       FIG. 16  is a view illustrating the essentially flat configuration of a fun box when disassembled; 
       FIG. 17  is a wire frame view of a corner connection, illustrating the fastening thereof; 
       FIG. 18  is a wire frame view that illustrates dual “hook and slot” fastening to provide vertical stability and allows assembly and rigidity even on somewhat non-flat surfaces and also illustrates alignment tabs on top surface and corresponding slots on verticals panels having significant lead-in to “self-align” upon assembly; 
       FIG. 19  is a wire frame view that illustrates lateral stability is obtained by closely locating tabs on adjoining panels to essentially lock them together to prevent lateral “racking” of the top panels; 
       FIG. 20  is a wire frame view that illustrates putting a grindrail into square tube pockets in the ramp or box to allow the rail adequate stability without having to be anchored by other means to a concrete or asphalt surface; and 
       FIG. 21  is a wire frame view of a quarter pipe constructed in accordance with the present invention. 
   

   DETAILED DESCRIPTION 
   The system according to a preferred embodiment of the present invention comprises a knock down “funbox”, ramp and grindrail system, wherein the components are combinable in various combination to make skate/bike/skateboard park structures. 
   The system is comprised of various laser cut steel parts that interlock without tools to form various pieces of equipment to skateboard on. Although this system could be used at skate parks, skateboard shops, a mall, exhibitions, its primary target is for driveway and backyard use at home. The advantage is that kids learning or kids trying to get better, either are intimidated at the skate park by other kids, or don&#39;t have access to a park. A major advantage for “at home” use, is that the system quickly breaks down without tools and stores flat so parents don&#39;t have to deal with huge, unsightly structures in the yard or garage. 
   The system can also be used for those that in-line skate or use stunt bikes on skate park like obstacles. The pieces can be assembled into various components of a skate park system, including a “funbox”, grind rail, and ramps. The same concept can be used to build virtually anything kids could want-quarter pipes, more elaborate rails, pyramids, etc. 
   Referring now to  FIG. 1 , a perspective wire frame view of an embodiment of the invention in an assembled form, the system includes a fun box  10 , which is assembled from four side portions, two side portions  12  and two side portions  12 ′ and two interlocking top portions  14 , only one top portion being present in the illustration of  FIG. 1  and a cross brace is not shown. A ramp  16  comprises two top portions  18 , two side pieces  36 , an intermediate support  20  and an end support  22 . A grindrail  24  is received in square cross section openings that are provided in the ramp or funbox. Covers may suitably be provided to cover the openings when not using the grindrail. The grindrail openings may be provided at any side of the ramp or funbox, so that left and right hand positioning may be accomplished, for example. The side and top portions and intermediate portions cooperatively mate as shown in the figures herein for a secure stable assembled structure. The side pieces use hook and slot engagement for assembly.  FIG. 17  illustrates that the sides of the funbox include chamfered slots therein, and the top portions include mating clips that have corresponding chamfered mating slots, so that on assembly the top and sides will self align and square. 
   Referring now to  FIG. 2 , a perspective view of a close up of the attachment hook system according to the invention, the illustrated corner of the fun box  10  of  FIG. 1  comprises a first side portion  12 , which has first and second hook members  26  protruding outwardly therefrom. The hooks are co-planar with the rest of the side  12 , being formed from the same sheet of material as the rest of the side  12 . A second side portion  12 ′ has defined therein two sets of corresponding mating slots  28 , which are adapted to receive respective hook members  26  therein. The opening  26 ′ at the bottom of the hook members interacts with the bottom of the slots  28 , to engage the two side portions together. The first and second sets of slots  28  are spaced laterally apart. Note also that side portion  12  has a set of upper and lower slot members  30  defined therein. 
   When assembling the fun box, the side  12  is moved in the direction of arrows  32  of  FIG. 2 , so as to bring the hook members  26  into engagement with one of the sets of slots  28 . As shown in  FIG. 3 , to assemble, one just inserts the hook into the slot.  FIG. 4  illustrates the hook is fully engaged into the slot. 
   Referring now to  FIG. 5 , a perspective view of building up the “funbox”, the particular configuration illustrated comprises four sides (two sides  12 , and two sides  12 ′). In the illustration of  FIG. 5 , two persons are connecting the last set of sides  12  and  12 ′. A center brace portion  12 ″, illustrated in phantom in  FIG. 5 , may also be installed, corresponding to the configuration of sides  12 , having hook members  26 ′ on each end thereof. Corresponding slots  28 ′ are provided in the middle portion of sides  12 ′, to receive the center brace hooks. 
   Referring now to  FIG. 6 , a view showing installation of top portions  18  of the “funbox”, it may be observed that the top comprises two panels  18  in the illustrated embodiment wherein the top panels  18  interlock slots in the box to make it rigid and to hold it square and wherein ramps may be plugged into any side of the box. One reason for having the top of the “funbox” as two panels is that two pieces keep the weight reasonable for children to manage. The edges of the top are turned down for safety and to give them the right radius to “grind” along with a skateboard. The top pieces interlock with slots in the box to make it rigid and to hold it square, as discussed herein in connection with  FIGS. 18 and 19  hereinbelow. 
     FIG. 7  is a view showing a ramp being attached to the box. Ramp  34  comprises left and right sloped side members  36 , upper cross member  38 , which has left and right upper grind rail receivers  40  positioned near the outer ends thereof, and a central cross member  42 . Central cross member  42  may also carry a corresponding grind rail receiver  40 ′, visible in  FIG. 11 . In the view of  FIG. 7 , the skateboarder is just finishing installing the central cross member, which attaches to the sides  36  by use of hook members defined in the cross member that correspond to hooks  26 , and receiving slots in the side member  36  that correspond in structure and function to slots  28  or  30  of the sides  12 ′,  12  ( FIG. 2 ). Ramps may be plugged into any side of the box, by engagement with one of the extra sets of slots  28  or slots  30  of the sides  12 ′ or  12  by hook members  44  defined at the upper end of the ramp side, visible in  FIG. 10 . Also, a notch  46  is defined in the sides  36 , at a position part way between the upper end of the ramp and the portion of the ramp where the central cross member  42  is located. 
   Referring now to  FIG. 8 , a view showing installing of the top of the ramp, two ramp top pieces  48  are provided and are installed by being laid in place over the ramp sides and cross members. One of the ramp pieces is installed in the foreground of  FIG. 8 , and the second is in the process of being installed. Tabs (not visible in  FIG. 8 ) corresponding to notches  46  are provided on the lower sides of the ramp top, whereby engagement of the tabs and slots  46  results in interlocking engagement. 
     FIG. 9  is a perspective view of the ramp assembled and attached to the fun box. A skateboarder is standing on the ramp in this view, having just finished installing the ramp top in place. 
     FIG. 10  illustrates a skateboarder using the assembled funbox  10  with one ramp  34  attached. The funbox can be used by itself, or in this case, as a box with one ramp. 
   Referring now to  FIG. 11 , a view illustrating building up a ramp to use by itself, a previously assembled ramp with “funbox” is visible in the background. A grind rail receiver  40 ′ is visible on the right side of the central cross member in this view. A corresponding receiver may suitably be provided at the left side, also. At the center of central cross member  42 , a notch  50  is provided, to receive portions of the top  48  therein, for stable engagement thereof. 
     FIG. 12  is a view showing using the ramp by itself as a “launch ramp”, wherein the skateboarder is airborne after leaving the ramp. The end hook members  44  of the ramp sides are visible in  FIG. 12 , and by inserting these hook member  44  in to the slots  28  or  30  of the fun box, the ramp may be securely attached to the box. 
   As noted before, the ramps have square tube sockets  40 ,  40 ′ defined in the upper and central cross members, to receive a “grind rail”.  FIG. 13  is a view showing attachment of a “grind rail”  52  to the fun box. The grind rail is an elongate bar, with 3 downwardly extending legs substantially evenly spaced therealong. The legs differ in length from shorter on one end to longer on the other end of the bar, such that when the grind rail is installed, it is at an angle with respect to the ground. This angle can match the angle of the ramp, or can be different from the angle of the ramp, or can even be substantially parallel to the ground, for example. Grind rails can be inserted to either side of the ramp. Visible in  FIG. 13  are grind rail receiving hole plugs  54 , which may be used to cover the grind rail receiving holes in the ramp top portions, when the grind rail is not used. 
   Many different configurations are possible with the system of the invention. For example,  FIG. 14  is a perspective view of two ramps attached to a “funbox” with a “grind rail” installed. 
     FIG. 15  is a view of a skateboarder “board sliding” the “grind rail” as an example of one of the uses of the ramp system. 
   A major advantage for “at home” use, is that the system quickly breaks down without tools and stores flat so parents don&#39;t have to deal with huge, unsightly structures in the yard or garage.  FIG. 16  is a view illustrating the essentially flat configuration of a fun box when disassembled, with the sides  12 ,  12 ′, top pieces  14 , and two brace portions  12 ″. In the configuration shown in  FIG. 16 , two braces  12 ″ may be used, spaced on either side of the center of the box, rather than a single brace portion as in the. Corresponding slots  28 ″ are provided in the sides to engage with the hooks of the cross members. 
     FIG. 17  is a wire frame perspective view of a corner connection, illustrating the fastening of hook members of side  12  into the corresponding slots  28  of side  12 ′. Dual “hook and slot” fastening provides vertical stability and allows assembly and rigidity even on somewhat non-flat surfaces. 
   Referring now to  FIG. 18 , a wire frame view that illustrates alignment tabs  56  on top surfaces and corresponding slots  58  on verticals panels (sides  12 ,  12 , cross members  12 ″, for example) having significant lead-in to “self-align” upon assembly. Lateral stability can be critical and is obtained by closely locating tabs on adjoining panels to essentially lock them together to prevent lateral “racking” of the top panels. As noted before, the tops typically are built in multiple panels in order to make weight reasonable for a child to assemble. 
     FIG. 19  is a wire frame view that illustrates lateral stability is obtained by closely locating tabs on adjoining panels to essentially lock them together to prevent lateral “racking” of the top panels. Note also that the central cross member  12 ″ may include a substantially wider notch or slot portion  58 ′ to accommodate tab members from the two top portions. 
     FIG. 20  is a wire frame view that illustrates putting a grindrail into square tube pockets  40  in the ramp or box to allow the rail adequate stability without having to be anchored by other means to a concrete or asphalt surface where the ramp is being set up. The grindrail plugs in without requiring any fasteners. In use, the grindrail can be plugged into either side of the ramp for left-hand or right-hand use. 
   Note also that as discussed hereinabove, the grindrail square tube pockets have plugs which can be used to cover the openings when the grind rail is not being used. 
   The grindrail suitably may have a variety of forms, such as a straight rail as shown or, for example, with kinks at either end. 
     FIG. 21  is a wire frame view of a quarter pipe constructed in accordance with the present invention, comprising end stands  60 , four curved ramp braces  62 , ramp plates  64 ,  66 ,  68  and  70 , and ramp top  72 . Front and rear upper cross braces  74 ,  76  are also provided. The front and rear cross braces engage the end stands  60 , by use of the hook member/engagement slot configuration as employed with the fun box although in this case, with three hooks and slots at either end of the cross braces for greater lateral strength. The upper ends of the ramp braces connect with the front cross brace, again by use of hook members and corresponding engagement slots. Each of the ramp plates interact with corresponding slots or notches in the ramp braces, by use of tabs on the ramp plates, corresponding to alignment tabs  56  as discussed hereinabove. 
   Edges of the various top members herein in the illustrated embodiments are flanged to create the required top sheet rigidity. Holes or slots are used in the top panels for manufacturing to accurately locate alignment tabs for welding, spot welding or other fixation. 
   The ramp system is suitably constructed by using punched, cut, or laser cut steel or other metal sheets, enabling close tolerances to be held on mating features so that tremendous stability and rigidity is achieved. 
   Complex shapes can be built up beyond what is shown in the exemplary embodiments from the interlocking features described-hooks and slots for vertical panels, and alignment tabs with mating slots for top panels. 
   While the examples herein illustrate the system as used for skateboarding, the system can also be used for those that in-line skate or use stunt bikes on skate park like obstacles. 
   The system according to the invention provides advantages over the prior art in that it will knockdown to flat for easy storage in a home driveway use environment, store, trade fair, or school. Each piece is light enough to be managed by one person/child for unaided assembly. The system can be broken down into manageable weight to allow for easy shipment. No tools are required for assembly and no screw connections are required to obtain required rigidity. This is particularly important for children to assemble the device. Further, the device removes the worry about incorrect or incomplete assembly. 
   Fast set-up and disassembly make home use practical. It can be disassembled and put away rapidly so driveway can be used, or for storage, etc. All top edges are suitably radiused to allow skateboards to slide along the edges. Also radii provide a degree of safety by eliminating sharp sheet metal edges. 
   The ramp is self-supporting and may be used independently of the “Fun Box” or interlocked together in a variety of positions to use as a unit. 
   While a preferred embodiment of the present invention has been shown and described, it will be apparent to those skilled in the art that many changes and modifications may be made without departing from the invention in its broader aspects. The appended claims are therefore intended to cover all such changes and modifications as fall within the true spirit and scope of the invention.