Abstract:
A chessboard having a playing platform and a stage or table which together maintain the flatness of the playing platform despite changing humidity conditions is disclosed. The playing platform is fabricated from a plurality of wooden pieces that are cut to exhibit a radial grain, and adhered to adjacent wooden pieces so that the radial grain has a mirrored image to the immediately adjacent wooden piece. The playing platform is allowed to expand and contract without placing undue pressure on the stage or table, and vice versa (i.e., unconstrained).

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Prov. Pat. App. Ser. No. 61/844,264 filed on Jul. 9, 2013, the entire contents of which are expressly incorporated herein by reference. 
     
    
     STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT 
       [0002]    Not Applicable 
       BACKGROUND 
       [0003]    The various embodiments discussed herein relate to a chessboard. 
         [0004]    Chessboards are fabricated from various materials. High end chessboards are preferably fabricated from wood. Unfortunately, wood expands and contracts as a function of humidity, grain direction and type of wood. As such, the chessboard fabricated from wood may warp or buckle as the chessboard experiences changing humidity conditions. 
         [0005]    Accordingly, there is a need for an improved chessboard. 
       BRIEF SUMMARY 
       [0006]    The various embodiments and aspects discussed herein address the needs discussed above, discussed below and those that are known in the art. 
         [0007]    A chessboard having a playing platform and a stage is disclosed which maintains the flatness of the playing platform despite changing humidity conditions. The playing platform may be fabricated from a plurality of square wooden pieces with major surfaces exhibiting radial grain. Each adjacent wooden piece is oriented in a mirror fashion so that any lateral, upward, and/or downward movement in each wooden piece is reflected by equal and opposite expansion and contraction of the immediately adjacent wooden piece. The playing platform may be mounted to the stage with a plurality of clips secured to the playing platform and inserted into a groove formed on the interior of the stage so that expansion and contraction of the playing platform does not place undue pressure on the stage, and the stage does not place undue pressure on the playing platform which might cause buckling or the loss of flatness. 
         [0008]    More particularly, a chessboard having a playing platform, stage and first through fourth clips is disclosed. The playing platform may have a plurality of square pieces of wood arranged in a square configuration. The plurality of square pieces of wood may be laterally attached to each other to form a flat chessboard playing surface. The stage may have four sides disposed on four sides of the playing platform. An interior side of the stage may have a groove. The first clip may be attached to the bottom surface of the playing platform on a first side of the playing platform with a first tab of the first clip slideably disposed within the groove of the stage on a first side of the stage. The second clip may be attached to the bottom surface of the playing platform on a second side of the playing platform with a second tab of the second clip slideably disposed within the groove of the stage on a second side of the stage. The third clip may be attached to the bottom surface of the playing platform on a third side of the playing platform with a third tab of the third clip slideably disposed within the groove of the stage on a third side of the stage. The fourth clip may be attached to the bottom surface of the playing platform on a fourth side of the playing platform with a fourth tab of the fourth clip slideably disposed within the groove of the stage on a fourth side of the stage. 
         [0009]    The first, second, third and fourth clips permit unconstrained expansion and contraction of the playing platform in the X-Y plane, due to environmental changes to maintain flatness of the playing platform. One or more first, second, third and fourth clips may be used to connect the stage and the playing platform. 
         [0010]    The plurality of square pieces of wood may include sixty-four squares pieces of wood. Thirty two square pieces of wood of the sixty-four pieces may have a first color. Thirty two square pieces of wood of the sixty-four pieces may have a second color which is different from the first color. 
         [0011]    In addition to or in lieu of the first through fourth clips or multiples thereof, four corner clips may be disposed at the four corners of the stage and playing platform. Each of the corner clips may be disposed within the grooves formed in the interior sides of each corner of the stage. Also, each of the corner clips may be attached to the bottom surface of the playing platform. 
         [0012]    Each of the sixty-four pieces of wood define a longitudinal grain direction which are aligned parallel to each other. Lateral pieces of wood may be bonded to each other so that immediately adjacent pieces of wood are positioned with the grains of the exposed surface in a mirrored orientation. The pieces of wood may be cut to exhibit a radial grain. The radial grain is herein defined as an average slope of the tangential grain being 30 degrees or less (preferably 20 degrees or less) to a perpendicular line drawn from a transverse section of the piece of wood. 
         [0013]    The groove of the stage is formed at an inner peripheral side of the stage. The stage may have a platform engaging surface upon which a mating portion of the playing platform engages (i.e., rests upon). 
         [0014]    In another aspect, a method of manufacturing a chessboard is disclosed. The method may comprise the steps of selecting sixty-four square pieces of wood; attaching the sixty-four square pieces of wood together in a 8×8 square configuration to form a playing platform; forming a stage that peripherally surrounds the playing platform; and securing the playing platform to the stage while allowing for unconstrained lateral expansion and contraction of the playing platform to mitigate warping of the playing platform due to environmental changes. 
         [0015]    The selecting step may include the step of selecting only wood pieces that exhibit a radial grain in the lateral transverse sections. The attaching step may include the step of aligning the radial grains in a mirror configuration with the immediately adjacent piece of wood. The securing step may include the step of attaching a clip to the playing platform and inserting a tab of the clip into a groove formed in an interior side of the stage. 
         [0016]    In another aspect, a playing platform of a chessboard is disclosed. The platform may comprise sixty four square pieces of wood cut to expose a radial grain upon its surface. The pieces may be arranged in an 8×8 pattern with the longitudinal grains parallel to each other. Adjacent pieces of wood may be arranged so that the radial grains of the exposed grain surface are oriented in a mirror configuration. The pieces of wood may be attached (e.g., bonded) to each other. 
         [0017]    Thirty two of the sixty four square pieces of wood may have a first color. Thirty two of the sixty four square pieces of wood have a second color. The sixty four pieces of wood may be arranged to have alternating first and second colors. 
         [0018]    The sixty four square pieces of wood of alternating color may be bonded to each other to form the playing platform. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    These and other features and advantages of the various embodiments disclosed herein will be better understood with respect to the following description and drawings, in which like numbers refer to like parts throughout, and in which: 
           [0020]      FIG. 1  is a top perspective view of a chessboard; 
           [0021]      FIG. 2  is a perspective view of a playing platform of the chessboard shown in  FIG. 1 ; 
           [0022]      FIG. 3  is a cross-sectional view of the chessboard shown in  FIG. 1 ; 
           [0023]      FIG. 4  is an enlarged top view of a corner of a stage of the chessboard shown in  FIG. 1 ; 
           [0024]      FIG. 5  is a bottom perspective view of the chessboard shown in  FIG. 1 ; and 
           [0025]      FIG. 6  is an enlarged bottom view of a corner of the stage of the chessboard. 
       
    
    
     DETAILED DESCRIPTION 
       [0026]    Referring now to the drawings, a wooden chessboard  10  is shown. The wooden chessboard  10  may undergo changes between humid and dry conditions yet still maintain a flat playing surface  12 . The chessboard  10  includes a playing platform  14  and a stage  16 . The playing platform  14  is designed and mounted to the stage  16  so that expansion and contraction in the lateral grain direction “X” is unconstrained while movement in the vertical direction is constrained so that regardless of whether the chessboard  10  undergoes changes in humidity, the expansion and contraction of the playing platform  14  is minimized and any expansion and contraction that does occur is regulated to maintain flatness of the playing surface  12 . Expansion and contraction transverse to the lateral grain direction “Y” is minimized by selection of the wood and the grain, as discussed below. 
         [0027]    More particularly, referring now to  FIG. 1 , the chessboard  10  may have two major sections, namely, the (1) playing platform  14  which is secured to the (2) stage  16  in such a manner tha the playing platform  14  remains unconstrained in the X-Y plane while the Z axis is constrained. The playing platform  14  may be fabricated from a plurality of square shaped wooden pieces  18 . For a chessboard  10  having a standard chessboard pattern, the playing platform  14  is fabricated from sixty-four square shaped wooden pieces  18 . Thirty-two of the square shaped wooden pieces  18  may have a first color. The remaining thirty-two square shaped wooden pieces  18  may have a second color. The first color may be lighter than the second color, or vice versa. The first and second colors may be determined by the type of wood selected for the first and second sets of square wooden pieces  18 . By way of example and not limitation, the light-colored wooden pieces  18  may be fabricated from white ash or maple. The dark colored wooden pieces  18  may be fabricated from black walnut. Additionally or alternatively, the difference in colors between the first and second sets of wooden pieces  18  may be derived from a staining process. In this event, the first and second sets of wooden pieces  18  may be fabricated from the same type of wooden material but stained differently to achieve the first and second colors. Preferably, the first and second sets of square wooden pieces  18  are fabricated from two different types of wooden material that produce a light-colored set of wooden pieces  18  for the first set of thirty-two wooden pieces  18  and a darker colored set of wooden pieces  18  for the second set of wooden pieces  18 . 
         [0028]    The types of wood selected for the first and second sets of square wooden pieces  18  may be selected so that radial shrinkage between the first and second sets of square wooden pieces  18  is less than 2 percentage points (preferably 1% or less) to each other and tangential shrinkage is less than 2.5 percentage points (preferably 2.1% or less). The following data is the approximate shrinkage as a percent of green dimension, from green to oven-dry moisture content. Black walnut has a tangential shrinkage of 7.8% and a radial shrinkage of 5.5%. White ash has a tangential shrinkage of 7.8% and a radial shrinkage of 4.9%. Hard maple has a tangential shrinkage of 9.9% and a radial shrinkage of 4.8%. Any two of these types of wooden materials may be used for the first and second sets of square wooden pieces  18 . Preferably, the first set is fabricated from black walnut which has a tangential shrinkage of 7.8% and a radial shrinkage of 5.5%. The second set is fabricated from white ash which has a tangential shrinkage of 7.8% and a radial shrinkage of 4.9%. 
         [0029]    The individual wooden pieces  18  are aligned to each other so that the longitudinal grains are parallel with respect to each other. In  FIG. 2 , directional arrow  19  indicates the direction of the longitudinal grain of the wooden pieces  18 . All of the individual wooden pieces  18  are arranged so that the longitudinal grains are oriented in the same direction. The first and second sets of wooden pieces  18  are arranged in a standard chessboard fashion. Additionally, the wooden pieces  18  are cut so as to exhibit a radial grain exposure. To determine if the wooden piece  18  has a radial grain exposure, the end (transverse section)  20  is inspected. If the average tangential grain is within 30° from perpendicular, and more preferably within 20° from perpendicular, then the wood piece  18  may be categorized having an exposed radial grain. By selecting and/or cutting the wood pieces  18  to have a radial grain exposure, lateral contraction and expansion of the wood pieces  18  in the X-Y plane is minimized compared to wood pieces  18  having a tangential grain exposure or rift grain exposure. 
         [0030]    The wooden pieces  18  may be arranged so that the radial grain exposures of immediately adjacent wooden pieces  18  have a minor orientation. In particular, wooden piece  18   a  has a radial grain that curves to the right, whereas, wooden piece  18   b  has a radial grain that curves to the left. Wooden piece  18   c  has a radial grain that curves to the right. Wooden piece  18   d  has a radial grain that curves to the left. By arranging the wooden pieces  18  to have a mirror image configuration, the playing surface  12  remains flat despite movement of the wooden pieces  18  when the chessboard  10  experiences changes in humidity. More particularly, any upward or downward movement within transverse section  18   a  is oppositely matched and reflected in  18   b  in such a manner as to minimize shear stress at the bonding interface. Similarly, shear stresses are minimized at all bonding planes throughout the entire platform. 
         [0031]    Preferably, each adjacent wooden piece  18  is oriented so that the grain is mirrored to the immediately adjacent wooden piece  18 . However, it is also contemplated that the grains may be mirrored for every two or more wooden pieces  18 . By way of example and not limitation, the first and second wooden piece  18  may have the grains in the same orientation. The third and fourth wooden pieces  18  may have the grains in the mirrored orientation compared to the first and second wooden pieces  18 . 
         [0032]    The wooden pieces  18  may be attached to adjacent wooden pieces. By way of example and not limitation, the wooden pieces  18  may be laterally attached to adjacent wooden pieces with adhesive or other attaching or bonding technologies known in the art or developed in the future. The upper and lower surfaces of the playing platform  14  may be sanded to a particular flatness. Also, nest  22  may be formed so that a periphery of the playing platform  14  may overhang the stage  16 . 
         [0033]    The stage  16  may be fabricated from four pieces of wood  24   a - d . The opposed ends of the wood pieces  24  may be mitered and joined to each other with glue (i.e. adhesive) and a spline  26  (see  FIG. 4 ). The exterior surface of the stage  16  is shown in  FIG. 4  as having a unique carving for aesthetic purposes but the exterior surface may also have any other shape such as a square off shape shown in  FIG. 1 . Each of the pieces of wood  24  of the stage  16  may have a corresponding nest  28  (see  FIG. 3 ). The nests  22 ,  28  may be formed on all four exterior sides of the playing platform  14  as well as on all four interior sides of the stage  16 . 
         [0034]    The bottom surface  30  of the playing platform  14  contacts an upwardly directed surface  32  of the stage  16 . The interface therebetween defines the contacting surfaces  34 ,  36  of the playing platform  14  and the stage  16 . The playing platform  14  rests upon the contact surface(s)  36  of the stage  16  defined by the upwardly directed surface  32  of the nest  28  in the stage  16 . In  FIG. 3 , a downwardly directed surface  38  of the nest  22  is shown as being in contact with an upper surface  40  of the stage  16 . However, this is not necessary. A gap may also exist therebetween so that the only contact between the playing platform  14  of the stage  16  is at the contacting surfaces  34 ,  36 . 
         [0035]    The playing platform  14  may be secured to the stage  16  to allow for unconstrained expansion and contraction in the X and Y directions by securing the playing platform  14  to the stage  16  with a plurality of clips  42  that engage the bottom surface  30  of the playing platform and a groove  44  formed in the stage  16 . As shown in  FIG. 5 , the clips  42  may be secured to all four sides of the playing platform  14 . As shown in  FIG. 3 , the clips  42  may have an S-shaped configuration and be secured to the bottom surface  30  of the playing platform  14  with the screw or other mechanical fastener  46 . The other end of the clip  42  is slidingly disposed within the groove  44 . 
         [0036]    Referring now to  FIG. 5 , one or more first clip, second clip, third clip, fourth clip  42   a - d  may be secured to the first side, second side, third side, fourth side of the playing platform  14  and the stage  16 . Preferably, each of the sides of the playing platform  14  and the stage  16  has two equally spaced apart first through fourth clips  42   a - d , as shown. Additionally, it is also contemplated that only the first and third clips  42   a,  c or the second and fourth clips  42   b,  d may be used to secure the playing platform  14  to the stage  16 . 
         [0037]    The distal end  56  of the clip  42  does not contact the inner surface  58  of the groove  44 . This allows the playing platform  14  to expand and not place pressure on the stage  16 , and vice versa. The stage  16  does not place pressure on the playing platform  14  which may cause the playing platform  14  to buckle (i.e., lose its flatness). 
         [0038]    Referring now to  FIG. 6 , the playing platform  14  and the stage  16  may be attached to each other with a corner clip  48 . The corner clip  48  may have a flat triangular configuration that fits within the groove  44  formed in the inner periphery of the stage  16 . After inserting the corner clip  48  into the grooves  44  of the stage  16 , a screw  50  is inserted into a hole  52  of the corner clip  48 . The screw  50  is tightened until light pressure is applied to the stage  16  by the corner clip  48 . The space between the playing platform  14  and the corner clip  48  has a gap where the threads of the screw  50  are visible. To hide the threads, a grommet  54  may be used to hide the threads from view. As shown in  FIG. 5 , each of the four corners of the stage  16  has a corner clip  48 . The distal edges  60  of the clips  48  and the inner surface  58  of the groove  40  do not contact each other to allow for the playing platform  14  to expand and not place pressure on the stage  16 , and vice versa. The stage  16  does not place pressure on the playing platform  14  which may cause the playing platform to buckle (i.e., lose its flatness). 
         [0039]    The playing surface  12  may hold to a flatness measured by the following technique. If there is a minor rise in the central area of the playing surface  12 , a straight edge may be laid upon the playing surface  12 , corner to corner diagonally and/or corner to corner parallel, to and ½ inch inside the outer edges. One side of the straight edge contacts the playing surface  12 , while the other end is lifted up due to the minor rise. A measurement of a gap between the straight edge and the playing surface  12  may be taken. The measured dimension of the gap may be divided by two to determine the minor rise. If there is a minor dip in the central area of the playing surface  12 , the straight edge may be laid upon the playing surface  12 , corner to corner diagonally and/or corner to corner, parallel to and ½ inch inside the outer edges of the playing platform  14 . The gap between the straight edge and the central area is then measured directly. By implementing or incorporating the various aspects discussed herein in relation to the chessboard  10 , a flatness of within 1 mm is achieved, even despite transporting the chessboard  10  between humid and arid conditions. 
         [0040]    The various aspects and embodiments discussed herein are discussed in relation to a standalone chessboard  10 . However, the various aspects and embodiments discussed herein may be applied to a chessboard integrated into a table wherein the upper surface of the table forms the stage  16 . The playing platform  14  is mounted to the table top (i.e., stage) in the manner discussed above. Additionally, the various aspects and embodiments may be applied to other wood projects requiring a flat surface or a flat surface incorporated into a frame (stage, table, etc.). 
         [0041]    It is also possible to mount the wooden platform as described above to a stage  16  or table constructed of materials other than wood such as various metals or composites. 
         [0042]    The above description is given by way of example, and not limitation. Given the above disclosure, one skilled in the art could devise variations that are within the scope and spirit of the invention disclosed herein, including various ways of attaching adjacent pieces of wood. Further, the various features of the embodiments disclosed herein can be used alone, or in varying combinations with each other and are not intended to be limited to the specific combination described herein. Thus, the scope of the claims is not to be limited by the illustrated embodiments.