Abstract:
According to one disclosed embodiment, a skateboard deck comprises a carbon-fiber shell surrounding a longitudinally-extending interior space. The carbon-fiber shell has an upper inner surface and a lower inner surface opposite the upper inner surface; and a longitudinal beam disposed within the interior space. The longitudinal beam has an upper flange bonded to the upper inner surface of the shell, a lower flange bonded to the lower inner surface of the shell, and a web interconnecting the upper flange and the lower flange. The skateboard deck further comprises a generally rigid exterior portion encasing the core member. The exterior portion comprises at least one layer of wood disposed above or below the shell.

Description:
RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. application Ser. No. 11/220,278, filed Sep. 6, 2005, which claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Application No. 60/609,219, filed Sep. 9, 2004, titled SKATEBOARD DECK CONSTRUCTION, and of U.S. Provisional Application No. 60/612,003, filed Sep. 10, 2004, titled SKATEBOARD DECK CONSTRUCTION, and of U.S. Provisional Application No. 60/662,118 filed Mar. 16, 2005, titled SKATEBOARD DECK CONSTRUCTION. The entire contents of each of the above-mentioned priority patent applications are hereby incorporated by reference herein and made a part of this specification. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    Certain embodiments disclosed herein relate to skateboard deck construction. 
         [0004]    2. Description of the Related Art 
         [0005]    Skateboard decks constructed from laminated wood are well known. However, these and other known skateboard decks suffer from drawbacks in terms of strength, weight, durability, etc. 
       SUMMARY OF THE INVENTION 
       [0006]    According to one embodiment, a skateboard deck comprises a core member comprising a hollow carbon fiber structure, and a generally rigid exterior portion encasing the core member. The exterior portion can optionally comprise a core surround which surrounds a perimeter edge of said core member, and an upper layer overlying said core member. The exterior portion can further optionally comprise a lower layer underlying the core member. The core member can optionally have a skateboard shape. The core member may further optionally comprise a reduced-size skateboard disposed within the exterior portion. 
         [0007]    According to another embodiment, a method of making a skateboard deck comprises forming a core member from carbon fiber; imparting a skateboard shape to the core member; and after the imparting, building an exterior portion onto the skateboard-shaped core member. The core member can optionally be hollow. The exterior portion can optionally comprise a core surround and an upper layer. The exterior portion can further optionally comprise a lower layer. 
         [0008]    According to another embodiment, a skateboard deck comprises a core member comprising a carbon fiber structure having an internal longitudinal beam, and a generally rigid exterior portion encasing the core member. 
         [0009]    According to another embodiment, a core member for a skateboard deck comprises a carbon fiber shell surrounding a longitudinally-extending interior space, and a longitudinal beam disposed within the interior space. The longitudinal beam can optionally be bonded to at least one inner surface of the shell. The longitudinal beam can optionally define a first beam surface bonded to a first inner surface of the shell, and a second beam surface bonded to a second inner surface of the shell. 
         [0010]    According to another embodiment, a skateboard deck comprises a carbon-fiber shell surrounding a longitudinally-extending interior space. The carbon-fiber shell has an upper inner surface and a lower inner surface opposite the upper inner surface; and a longitudinal beam disposed within the interior space. The longitudinal beam has an upper flange bonded to the upper inner surface of the shell, a lower flange bonded to the lower inner surface of the shell, and a web interconnecting the upper flange and the lower flange. The skateboard deck further comprises a generally rigid exterior portion encasing the core member. The exterior portion comprises at least one layer of wood disposed above or below the shell. 
         [0011]    According to another embodiment, a core member for a skateboard deck comprises a carbon-fiber shell surrounding a longitudinally-extending interior space. The carbon-fiber shell has an upper inner surface and a lower inner surface opposite the upper inner surface. The core member further comprises a longitudinal beam disposed within the interior space. An upper portion of the longitudinal beam is bonded to the upper inner surface of the shell, a lower portion of the longitudinal beam is bonded to the lower inner surface of the shell. The longitudinal beam has a longitudinal cross section with an “S” configuration. 
         [0012]    According to another embodiment, a skateboard deck comprises a carbon-fiber shell surrounding a longitudinally-extending interior space. The carbon-fiber shell has an upper inner surface and a lower inner surface opposite the upper inner surface, a longitudinal beam disposed within the interior space, and first and second truck blocks disposed within the interior space. The first and second truck blocks are located at first and second ends of the longitudinal beam. The skateboard deck further comprises a generally rigid exterior portion encasing the core member. The exterior portion comprises at least one layer of wood disposed above or below the shell. 
         [0013]    Certain objects and advantages of the invention are described herein. Of course, it is to be understood that not necessarily all such objects or advantages may be achieved in accordance with any particular embodiment of the invention. Thus, for example, those skilled in the art will recognize that the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objects or advantages as may be taught or suggested herein. 
         [0014]    All of the embodiments summarized above are intended to be within the scope of the invention herein disclosed. However, despite the foregoing discussion of certain embodiments, only the appended claims (and not the present summary) are intended to define the invention. The summarized embodiments, and other embodiments of the present invention, will become readily apparent to those skilled in the art from the following detailed description of the preferred embodiments having reference to the attached figures, the invention not being limited to any particular embodiment(s) disclosed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]      FIG. 1  is an exploded view of the construction of a skateboard deck. 
           [0016]      FIG. 2  is an exploded view of the construction of a core member of the skateboard deck of  FIG. 1 . 
           [0017]      FIG. 3  is an exploded view of the construction of a core surround of the skateboard deck of  FIG. 1 . 
           [0018]      FIG. 4  is a perspective view of another embodiment of a core member suitable for use in the skateboard deck of  FIG. 1 , with an upper portion of a shell of the core member partially cut away and a center layer of the core member removed for clarity. 
           [0019]      FIG. 5  is a top view of the core member of  FIG. 4 , with the upper portion of the shell partially cut away for clarity. 
           [0020]      FIG. 6  is a cross sectional view of the core member of  FIG. 4 , taken along the line  6 - 6  in  FIG. 5 . 
           [0021]      FIG. 7  is a cross sectional view of the core member of  FIG. 4 , taken along the line  7 - 7  in  FIG. 5 . 
           [0022]      FIG. 8  is a perspective view of a skateboard deck incorporating a version of the core member of  FIGS. 4-7 . 
           [0023]      FIG. 9  is a top view of the skateboard deck of  FIG. 8 . 
           [0024]      FIG. 10  is a side view of the skateboard deck of  FIG. 8 . 
           [0025]      FIG. 11  is a sectional view of the skateboard deck of  FIG. 8 , taken along the line  11 - 11  in  FIG. 9 . 
           [0026]      FIG. 11A  is a detail view of the indicated portion of  FIG. 11 . 
           [0027]      FIG. 11B  is a schematic detail view of the indicated portion of  FIG. 11 , showing the construction of the longitudinal beam and its position in the center layer of the core member. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0028]      FIG. 1  depicts one embodiment of a skateboard deck  50 , which generally comprises a core member  60 , a core surround  70  which surrounds the periphery of the core member  60 , upper layers  80  which overlie the top of the core member  60  and core surround  70 , and lower layers  90  which underlie the bottom of the core member  60  and core surround  70 . 
         [0029]    In the embodiment depicted in  FIG. 1 , the core member  60  may have a skateboard shape, i.e. it may comprise a miniature skateboard unto itself. Thus the core member  60  may have upturned front and rear ends  62 ,  64 , a slightly concave upper surface, a slightly convex lower surface, and a planform having a shape approximating an elongated oval. In one embodiment, the core member may comprise a skateboard-shaped member or miniature skateboard deck formed from carbon fiber. 
         [0030]    The core member  60  may be further configured as shown in  FIG. 2 , with a foam (e.g., polyester foam) center layer  66  and upper and lower carbon fiber layers  67 ,  68  which wrap around the center layer  66 . The core member  66  may be constructed by wrapping the carbon fiber layers  67 ,  68  around the center layer  66 , with resin and/or other adhesives between the carbon fiber layers  67 ,  68  (and/or between the carbon fiber layers  67 ,  68  and the center layer  66 ), so that the “wrapped” assembly takes on the approximate, elongated-oval planform of the center layer  66 . After wrapping, the core member  66  is pressed into the “skateboard” shape described above and depicted in  FIG. 1 . 
         [0031]    Thus, in the embodiment depicted in  FIG. 1 , the core member  60  comprises a hollow, enclosed multi-layer carbon fiber member with a “skateboard” shape. (The core member  60  is “hollow” in that its center is an empty space or is occupied by a material other than carbon fiber, or by a material which is less dense than carbon fiber.) The core member  60  thus achieves great strength and light weight with a minimum of carbon fiber material, as compared to a simple single layer or layered “sandwich” of multiple carbon fiber layers. 
         [0032]    In one embodiment, the carbon fiber layers  67 ,  68  may comprise three upper and three lower layers, and each of the six layers may be 0.5 mm thick. The resulting core member  60  has a thickness of 0.185 inches. 
         [0033]      FIG. 3  depicts the construction of the core surround  70  in greater detail. A number (e.g., 3, as depicted) of sheets of wood, fiberglass, plastic, etc. are glued and pressed together to form an enlarged (as compared to the core member  66 ) skateboard shape within the perimeter of the core surround  70 . From within this enlarged skateboard shape is cut out a smaller skateboard shape approximating the size of the core member  66 . Thus is formed an inner edge  72  of the core surround  70 , which inner edge  72  closely abuts the outer edge of the core member  66  when the core member  66  is placed inside the core surround  70 . The core surround  70  thus extends outward from the perimeter of the core member  60 , in the completed deck  50 . 
         [0034]    Upon placement of the core member  60  inside the core surround  70 , the upper and lower layers  80 ,  90  are pressed and bonded together with the core-member-core-surround assembly disposed between them, so that the upper and lower layers  80 ,  90  conform closely to the contoured shape defined by the core-member-core-surround assembly. The resulting structure is then permitted to cure for an appropriate length of time, and the upper and lower layers  80 ,  90  and core surround  70  are cut to create a skateboard planform for the overall deck  50 . One example of a cut pattern is shown with the dashed lines  92 . Any suitable molding and/or lamination processes may be used to join the core member  60 , core surround  70  and upper and lower layers  80 ,  90 . 
         [0035]    After cutting, the completed deck  50  comprises the core member  66 , encased by the core surround  70  and the upper and lower layers  80 ,  90 . Thus the deck  50  comprises a “skateboard within a skateboard” (the skateboard-shaped core member  66  disposed within the layers  80 ,  90  and the core surround  70 ). Trucks, wheels, rails, etc. may be added to the deck  50  to create a complete skateboard. 
         [0036]    In one embodiment, the core surround  70  may comprise three layers of North American hard maple wood, of 0.062 inches thickness each, to create a core surround  70  of 0.0185 inches thick. In this embodiment the upper and lower layers  80 ,  90  may also be formed from North American hard maple wood, with the uppermost upper layer  80  and the lowermost lower layer  90  0.062 inches thick, and the balance of the layers  80 ,  90  0.042 inches thick. The overall thickness of the deck  50  may be about 0.393 inches. 
         [0037]      FIGS. 4-7  depict another embodiment of a core member  160 , which can be generally similar to the core member  60 , except as further described below. As with the core member  60  described above, the core member  160  of  FIGS. 4-7  generally comprises a foam center layer  166  surrounded and enclosed by a carbon fiber shell  110 . In one embodiment the shell  110  may be formed by wrapping a number of upper and lower layers of carbon fiber material around the center layer  166  and pressing and bonding together the resulting structure, e.g. as shown and described above with regard to the core member  60 . 
         [0038]    In the depicted embodiment the core member  160  also includes a pair of hardpoints or truck blocks  112  which reside within the shell  110  and are situated in suitable spaces or openings formed in the center layer  166 . The truck blocks are positioned on the longitudinal centerline of the core member  160 , and are preferably formed from a rigid and resilient material (e.g. wood, heavy plastic, fiber-reinforced plastic) to receive screws (not shown) that are driven into the deck  50  to hold a pair of trucks to the deck. To accommodate assembly of the center layer  166  around the truck blocks  112 , the material of the center layer may be divided into halves by a longitudinal seam  114 . As best seen in  FIG. 6 , in one embodiment the truck blocks may each comprise two stacked layers of wood. Preferably, each of the truck blocks extend from an inner upper surface  116  of the shell  110  to an inner lower surface  118  thereof, so that the blocks abut the shell material at each of the surfaces  116 ,  118 . 
         [0039]    As best seen in  FIGS. 4 and 7 , in one embodiment the core member  160  may further comprise a longitudinal beam  120  that extends generally along the longitudinal centerline of the member  160 , from one of the truck blocks  112  to the other. (In another embodiment, the longitudinal beam  120  can further extend longitudinally from each truck block  112  to the adjacent end of the core member  160  (see  FIG. 9 ).) The depicted longitudinal beam  120  has an “S” cross section along its entire length, thereby forming upper and lower flanges  122 ,  124  interconnected by a web  126 . In other embodiments, the beam  120  may have a different cross section, such as an, “I,” “T,” “U,” etc., or a box section. 
         [0040]    During construction of the core member  160  the upper flange  122  may be securely bonded to the inner upper surface  116  of the shell  110 , and the lower flange  124  securely bonded to the inner lower surface  118 , to impart great strength and rigidity to the core member. 
         [0041]    In one embodiment, the core member  160  may have the following dimensions: overall length of 740 mm; overall width of 140 mm; overall thickness of 4 mm; truck block length of 90 mm; truck block width of 70 mm; and center layer thickness of 3 mm. In this embodiment, the longitudinal distance between the truck blocks is preferably 320 mm. 
         [0042]    Further details of the construction of one embodiment of the deck  50  and core member  160  may be seen in  FIGS. 8-11B . (The deck  50  and core member  160  of  FIGS. 8-11B  can be similar to the deck  50  and core members  60 ,  160  depicted in  FIGS. 1-7 , except as further described below.) In this embodiment, the center layer  166  of the core member  160  is situated between upper layers  167   a ,  167   b ,  167   c  and lower layers  168   a ,  168   b ,  168   c  (see  FIG. 11A ). The upper layers  167   a ,  167   b  and the lower layers  168   a ,  168   b  preferably comprise carbon fiber material, and more preferably comprise layers of VTM246 200gsm unidirectional “prepreg” carbon fiber fabric, trimmed to the profile of the center layer  166  with 10 mm overlap on the edges. The innermost upper layer  167   c  and lower layer  168   c  preferably also comprise carbon fiber material, and more preferably comprise layers of MTM56 200 gsm 2/2 twill prepreg carbon fiber fabric, trimmed to the profile of the center layer  166  with 10 mm overlap on the edges. In addition, the center layer  166  preferably comprises 3 mm thick polyester foam with a density of 80 kg per cubic meter. 
         [0043]    In the embodiment of  FIGS. 8-11B , the longitudinal beam  120  can have a 3-layer configuration as shown in  FIG. 1   l  B, with an inner layer  121   a  situated between two outer layers  121   b . The inner layer  121   a  preferably comprises carbon fiber material, and more preferably comprises a layer of MTM56 200 gsm 2/2 twill prepreg carbon fiber fabric, trimmed to a width of 40 mm. The outer layers  121   b  preferably comprise carbon fiber material, and more preferably comprise layers of VTM246 200gsm unidirectional prepreg carbon fiber fabric, trimmed to a width of 40 mm. 
         [0044]    The core member  160  can be constructed by a lay-up process. This process preferably comprises: (a) preparing the truck blocks or hardpoints  112  with appropriately sized (e.g., 90 mm×70 mm) plywood blocks wrapped in adhesive film (e.g., MTM26 resin adhesive film); (b) cutting openings in the material of the center layer  166  to accommodate the truck blocks  112 ; (c) positioning the longitudinal rib  120  between the two halves of the center layer  166  as shown in  FIG. 11B  (preferably overlapping the upper and lower faces of the center layer  166  by a distance D of 15 mm); (d) inserting the prepared truck blocks into the openings in the center layer  166 ; (e) applying the innermost lower layer  168   c  with overlap as shown in  FIG. 11A ; (f) applying the innermost upper layer  167   c  with overlap over the innermost lower layer  168   c  as shown in  FIG. 11A ; (g) applying the next lower layer  168   b  with overlap over the underlying layers  167   c ,  168   c  as shown in  FIG. 11A ; (h) applying the next upper layer  167   b  with the depicted overlap; (i) applying the next lower layer  168   a  with the depicted overlap; and (j) applying the next upper layer  167   a  with the depicted overlap. 
         [0045]    After layup, the core member  160  can be placed in a matched-pair mold under vacuum (preferably 1 ATM) and cured at a temperature of 120 C for 15 minutes. After molding and curing, the core member  160  is permitted to cool and is trimmed as necessary for attachment of the upper and lower layers  80 ,  90  and the core surround  70 . The core member  160  may be sanded or otherwise roughened to eliminate any “glossy” spots and improve the adhesion of the core member  160  to the upper and lower layers  80 ,  90 . 
         [0046]    Once the completed core member  160  is ready, the upper and lower layers  80 ,  90  and the core surround  70  can be built onto the core member as discussed above with reference to  FIG. 1 , to create a complete skateboard deck  50 . 
         [0047]    Although this invention has been disclosed in the context of certain preferred embodiments and examples, it will be understood by those skilled in the art that the present invention extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses of the invention and obvious modifications and equivalents thereof. Thus, it is intended that the scope of the present invention herein disclosed should not be limited by the particular embodiments described above, but should be determined only by a fair reading of the claims that follow.