Abstract:
A corrugated skateboard deck and method of corrugating skateboard decks in the skateboard deck manufacturing process. The corrugated skateboard deck has elongated corrugations embossed into at least one of its top and bottom surfaces and generally extending between first and second ends of the skateboard deck. The elongated corrugations are made up of ridges and grooves which are pressure-formed in a method of corrugating the surfaces of skateboard decks. This method utilizes a high-density corrugated template to emboss corrugations under high pressures.

Description:
BACKGROUND OF THE INVENTION 
     The field of the invention generally pertains to skateboard decks and methods of manufacturing skateboard decks. The invention relates more particularly to a corrugated skateboard deck and a method of corrugating the surfaces of skateboard decks in a skateboard deck manufacturing process. 
     The popularity of skateboarding has grown continuously in recent years, as well as the demand for high-performance skateboards. In part, this has been due to the evolution of skateboarding into an extreme sport involving amazing and dare-devilish techniques and maneuvers. One popular skateboarding maneuver in particular involves sliding on rails and ledges using the bottom surface of a skateboard deck as the sliding surface. However, this and other high-impact skateboarding maneuvers can create extreme levels of stress in skateboard decks. A high degree of torsional rigidity, durability, and performance features is therefore required in skateboard decks to withstand the extreme conditions associated with today&#39;s modern skateboarding styles without sacrificing skateboarding performance. 
     Various skateboard deck designs and manufacturing methods have been developed to improve the strength, durability, and/or performance of skateboard decks. Some particular developments in skateboard deck design have been angled “nose” and “tail” ends of skateboard decks, and “concave decks” having upwardly curving side edges. These features are typically pressure-formed in a mold, with a bonding agent functioning to join and set multiple plies of wood in the shape of the mold. However, while these features enable skateboarders to better control their skateboards when performing skateboard tricks and maneuvers, it has little effect on the strength and durability of the skateboard deck. 
     Additionally, various types of wood plies and bonding agents have been used to improve the strength and durability of skateboard decks. However, measures to strengthen, enhance, and reinforce skateboard decks have typically come at a high cost to skateboard deck weight, which can hurt skateboarding performance. 
     BRIEF SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide an improved skateboard deck having a plurality of elongated corrugations which increase torsional rigidity and enable improved performance of various skateboard techniques and maneuvers. 
     It is a still further object of the present invention to provide a simple, efficient, and economic method of corrugating the surfaces of skateboard decks in a skateboard deck manufacturing process, thereby increasing torsional rigidity of the skateboard deck and enabling improved performance of various skateboard maneuvers and techniques. 
     The present invention is for an improved skateboard deck having a generally planar configuration with a first end, a second end opposite the first end, a first elongated side edge between the first and second ends, a second elongated side edge between the first and second ends and opposite the first elongated side edge, a top surface, and a bottom surface. At least one of the top and bottom surfaces has a plurality of elongated corrugations between the first and second ends. And the plurality of elongated corrugations comprises a plurality of ridges and grooves which extend generally longitudinally between said first and second ends, and each ridge of said plurality of ridges having a single contact point at its apex when viewed in cross-section. 
     Additionally the present invention is for a method of corrugating skateboard decks in a skateboard deck manufacturing process. In a first preferred embodiment, the method comprises the initial step of placing a high-density corrugated template between a top ply of a first set of wood plies and a bottom ply of the second set of wood plies. Each of the first and second sets of wood plies is prepared with a bonding agent in-between the wood plies. Next, a pressure is applied on the first and second sets of wood plies while the bonding agent sets. This is followed by the steps of releasing the pressure, and removing the high-density corrugated template. Similarly, in a second preferred embodiment, a high-density corrugated template is placed on an outer ply of a set of wood plies which is prepared with a bonding agent in-between the wood plies. A pressure is then applied on the high-density corrugated template and the set of wood plies while the bonding agent sets. Finally, the pressure is released and the high-density corrugated template is removed. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a complete skateboard as generally seen from the top, assembled with the corrugated skateboard deck. 
     FIG. 2 is a perspective view of a complete skateboard as generally seen from the bottom, assembled with the corrugated skateboard deck. 
     FIG. 3A is a perspective view of the corrugated skateboard deck, depicting a first preferred embodiment of the plurality of elongated corrugations. 
     FIG. 3B is a top view of the corrugated skateboard deck in FIG. 3A, depicting a first preferred embodiment of the plurality of elongated corrugations. 
     FIG. 4 is a cross-sectional view of the corrugated skateboard deck taken along the line of  4 — 4  of FIG. 3B, depicting a first preferred embodiment of the plurality of ridges and grooves. 
     FIG. 5 is an enlarged cross-sectional view of the corrugated skateboard deck taken along the circle  5  of FIG.  4 . 
     FIG. 6A illustrates a second preferred embodiment of the plurality of ridges and grooves as seen from a cross-sectional view of the corrugated skateboard deck similar to the cross-sectional view shown in FIG.  5 . 
     FIG. 6B illustrates a third preferred embodiment of the plurality of ridges and grooves as seen from a cross-sectional view of the corrugated skateboard deck similar to the cross-sectional view shown in FIG.  5 . 
     FIG. 7A illustrates a second preferred embodiment of the plurality of elongated corrugations as seen from a top view of the corrugated skateboard deck, similar to the top view shown in FIG.  2 . 
     FIG. 7B illustrates a third preferred embodiment of the plurality of elongated corrugations as seen from a top view of the corrugated skateboard deck, similar to the top view shown in FIG.  2 . 
     FIG. 8 illustrates a popular skateboarding maneuver utilizing the bottom surface of the corrugated skateboard deck for sliding. 
     FIG. 9A is a perspective view of a first preferred embodiment of the high-density corrugated template having two corrugated faces and in its unbiased state. 
     FIG. 9B is an enlarged perspective view taken along the circle  9 B in FIG. 9A of a first preferred embodiment of the high-density corrugated template having two corrugated faces and in its unbiased state. 
     FIG. 10A is a cross-sectional, exploded view of a layered combination of the high-density corrugated templates and the two sets of wood plies prior to applying a pressure in a pressure-mold in the method of corrugating skateboard decks in a skateboard deck manufacturing process. 
     FIG. 10B is a cross-sectional view of the high-density corrugated templates and the two sets of wood plies as a pressure is applied in a pressure-mold in the method of corrugating skateboard decks in a skateboard deck manufacturing process. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings, FIGS. 1 and 2 show perspective views of a complete skateboard, generally indicated by reference character  9 , as generally seen from the top and bottom, respectively. As can be seen in FIGS. 1 and 2, the complete skateboard  9  is assembled from several skateboard components, including the corrugated skateboard deck, generally indicated by reference character  10 , and other skateboard components, including a pair of trucks  11 ,  12 , four wheels  13 - 16 , and four wheel bearings (not illustrated). 
     As can be seen from FIGS. 1-3B, the corrugated skateboard deck  10  has a generally planar configuration including a first end  17 , a second end  18  opposite the first end  17 , a first elongated side edge  19  between the first and second ends  17 ,  18 , a second elongated side edge  20  between the first and second ends  17 ,  18  and opposite the first elongated side edge  19 , a top surface  21 , and a bottom surface  22 . 
     Additionally, at least one of the top  21  and bottom  22  surfaces of the corrugated skateboard deck  10 , has a plurality of elongated corrugations  23  between the first and second ends  17 ,  18  (see FIG.  2 ). The plurality of elongated corrugations  23  functions to increase the longitudinal stiffness and torsional rigidity of the skateboard deck  10 , thereby decreasing the effects of stress experienced by the skateboard deck  10 . 
     As can be best seen in FIGS. 3A-B, showing the skateboard deck  10  alone, a first preferred embodiment of the plurality of elongated corrugations  23  generally extends longitudinally between the first and second ends  17 ,  18  in a parallel pattern. Alternatively, FIGS. 7A and 7B show second and third embodiments, respectively, of the plurality of elongated corrugations  23  as seen from a top view of the skateboard deck  10 . As can be seen in FIGS. 7A-B, the skateboard deck  10  can have curvilinear corrugation patterns (FIG. 7A) or a logo or other graphic image design (FIG.  7 B), but is not limited only to such. The pattern of the elongated corrugations  23  can be widely varied, and the placement can be concentrated along high-impact stress points, such as the points of truck attachment. 
     The plurality of corrugations  23  shown in FIGS. 1-3B, and  7 A-B are further comprised of a plurality of ridges  24  and grooves  25 , as shown in FIGS. 4-6B. A first preferred embodiment of the plurality of ridges  24  and grooves  25  is shown in FIGS. 4-5. As can be best seen in FIG. 5, showing a detailed, enlarged view of the skateboard deck  10  in FIG. 4, each ridge  24  of the first preferred embodiment preferably has a convex cross-section and a curvilinear apex, but is not limited only to such. As can be seen in FIGS. 6A-B showing second and third embodiments of the plurality of ridges  24  and grooves  25 , the ridges  24  can also have generally pointed apexes and generally conical cross-section (FIG.  6 A), as well as a continuous wave-like cross-section (FIG.  6 B). 
     One advantage of having elongated corrugations  23  along the bottom surface  22  of a skateboard deck  10  is that it provides less contact area when performing sliding maneuvers along the bottom surface  22  of the skateboard deck  10 . Contact area is reduced because of the separation and distance between the apexes of each ridge  24  by an intermediate groove  25  (See FIG.  5 ). FIG. 8 illustrates a popular skateboarding maneuver known as a “rail slide,” where a skateboarder  27  uses the skateboard  9 , to leap onto and slide along a handrail  28 . The plurality of elongated corrugations  23  on the bottom surface  22  enable smoother and faster slides when performing this maneuver. Additionally, because the plurality of corrugations  23  strengthen torsional rigidity of the skateboard deck  10 , it is able to better withstand the stress and impact commonly associated with such rail slides. 
     Preferably, corrugated skateboard decks  10  are manufactured using a method of corrugating skateboard decks as shown in FIGS. 10A-B. FIGS. 10A-B show a preferred embodiment of the method utilizing high-density corrugating templates  29 ,  36 ,  37  and first and second sets of wood plies, generally indicated by reference characters  34  and  35 , respectively. The high-density corrugating templates  29 ,  36 ,  37  are preferably formed from high-density polyethylene or other high-density plastic, with the corrugation design milled on two-sides ( 29 ) or only one-side ( 36 ,  37 ). FIGS. 9A-B show a first preferred embodiment of the high-density corrugated template  29  having two corrugated faces, an upper corrugated face  40 , and a lower corrugated face  41 . As can be best seen in FIG. 9B, both the upper and lower corrugated faces  40 ,  41  have ridges with pointed apexes  25 ′ and curvilinear grooves  24 ′ which emboss the grooves  25  and curvilinear ridges  24 , respectively (see FIG.  5 ). Various corrugation designs can be easily milled into corrugation templates with the use of CAD/CAM systems. 
     As can be best seen in FIGS. 10A-B, the two sets of wood plies  34 ,  35  each have multiple layers or plies of wood, (commonly seven layers) which are prepared with a bonding agent in-between the wood plies. Although only two sets of wood plies  34 ,  35  are illustrated in FIGS. 10A-B, additional sets of wood plies may be further stacked on top of first and second sets of wood plies  34 ,  35  to produce a greater number of skateboard decks  10  per pressing. As can be seen in FIG. 10A, the two-sided high-density corrugated template  29  is placed in-between a bottom ply  30  of the first set of wood plies  34  and a top ply  31  of the second set of wood plies  35 . The two one-sided high-density corrugated templates  36 ,  37  are placed at remaining outer plies  32  and  33 , respectively. This layered combination is placed in a mold having an upper mold  38  and a lower mold  39 . 
     Subsequently, as can be best seen in FIG. 10B, a pressure P is then applied to the two sets of wood plies  32 ,  33  to shape the two sets of wood plies  34 ,  35  to that of the mold  38 ,  39 . As can be seen in FIGS. 9A and 10A, the high-density corrugating templates  29  (also FIG.  9 B),  36 ,  37  have a generally straight and flat-shaped cross-section prior to applying the pressure P. However, as can be seen in FIG. 10B, the high-density corrugated templates  29 ,  36 ,  37  are sufficiently flexible to bias and conform to the contour of the mold  38 ,  39 . 
     The pressure P is applied until the bonding agent sets and can retain the shape of the mold  38 ,  39 . It is during this pressure-molding process that the high-density corrugated templates  29 ,  36 ,  37  emboss the plurality of elongated corrugations  23  onto the bottom surface  30  of the first set of wood plies  34 , the top surface  31  of the second set of wood plies  35 , and the outer plies  32 ,  33  of the first and second sets of wood plies  34 ,  35 , respectively. After the bonding agent has set, the applied pressure P is released, and the high-density corrugated templates  29 ,  36 ,  37  are removed. The properties of the high-density corrugated templates  29 ,  36 ,  37  will typically return to its original unbiased shape as shown in FIG. 9A for repeated use in subsequent pressings. 
     The present embodiments of this invention are thus to be considered in all respects as illustrative and not restrictive; the scope of the invention being indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are intended to be embraced therein.