Patent Publication Number: US-2021170264-A1

Title: Portable chess set that preserves positions of chess pieces during a pause in game play to permit transportation and continuation of a chess game

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This application claims priority from Provisional Patent Application 62/945,403, entitled “Travel Chess Set”, filed Dec. 9, 2019, the entire contents of which is herein incorporated by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to chess sets, and more particularly to portable chess sets adapted to preserve the positions of chess pieces on a game board during transportation of the game board between periods of game play. 
     BACKGROUND OF THE INVENTION 
     Chess is probably the world&#39;s oldest game, and over the years has been played by many millions of people. A chess game simulates a relatively simple war situation where two opponents each start with a set of royalty figures, i.e., a king, a queen, a pair of bishops, a pair of knights, and a pair of rooks, plus a set of pawns which are initially positioned to protect the more powerful royalty figures. 
     A typical chess set includes two sets of chess pieces and a board with 64 spaces or squares of alternating colors, typically light wood and dark wood, or black and white paint, although other colors may be used. One set of chess pieces are dark or black, and the other set are light or white. 
     One problem with chess arises particularly when using portable (travel) chess sets. Portable chess boards typically fold once in the middle. The resulting chess board is still long enough to be bulky and awkward. When played upon, such chess boards show an unsightly crease or hinge in the middle. Portable chess boards may also be made of thin, flexible material that is cumbersome when rolled up. When unfurled at the site of play, such chess boards have a tendency to curl back to their original rolled shape. This is especially common when all the pieces are located in the center during middle game. 
     Combination board and container chess sets usually include a box large enough to accommodate a reasonably sized board, which often allows the chess pieces to tumble, slide, and damage one another in the empty space. Some chess boards have a ferrous or ferromagnetic underlayer which is intended to be used with magnetized chess pieces. However, these chess sets often exhibit inadequate magnetic attraction, which can result in a disastrous spill of the chess pieces when playing in an unstable location, thereby causing arguments about the positions of the pieces before the spill, and often result in a tedious search for missing pieces. 
     Another problem encountered while playing chess occurs when one player positions a chess piece near or even upon the borders of a square. The opposing player can get thrown off by its ambiguous placement. The opposing player must say, “J′adoube” (adjust) before he or she may touch the ill-placed piece, and then place it more clearly in the square. Doing so, however, deprives the opponent of time allocated to him/her by previous agreement. 
     U.S. Pat. No. 2,511,774 for a “Magnetic Game Board and Cover Therefor” issued to Goldsmith teaches a plurality of “cross bars” in the cover to preserve the respective positions of the pieces when the cover is closed, but such cross-bars would be relatively expensive to manufacture. This device also requires that all the pieces be the same height. If the pieces were of “standard” heights (i.e., chess pieces being of various heights), then the shorter pieces would have head-room in which they could rattle around if they lose contact with the playing surface. This device also relies on magnets that are embedded in the base of the chess board, which results in a chess board that is relatively thick to accommodate the magnets, thereby adding weight and excess thickness to what should ideally be a lightweight and compact travel chess set. 
     SUMMARY OF THE INVENTION 
     The invention is a portable chess set which provides magnetically stabilized and centered securement of the chess pieces, without sacrificing ease of play during use, also providing an elegant and aesthetic chess piece position preserver for maintenance of the positions of the chess pieces on the chess board during a pause in game play. 
     The portable chess set of the invention provides an easily-manufactured apparatus for preserving the positions of chess pieces between periods of play, which can accommodate chess pieces of varied height (e.g., knights are typically shorter than queens, and pawns are typically shorter than knights). 
     The invention avoids various drawbacks of the prior art (e.g., Goldsmith). 
     For example, the portable chess set of the invention uses an elegantly simple single-plane of material having a hole centered over each square of a chess board for limiting the potential movement of each chess piece during a temporary cessation of game play, regardless of movement of the chess set. Further, inclusion of a single-plane of material with a hole centered over each square greatly reduces the complexity and cost of manufacturing of the chess set, while also enhancing the visual appeal of the set. 
     Also, the portable chess set of the invention allows for the pieces to be various heights, as is typical in the classic design of the game. This is important during play, as chess pieces of different heights enhances recognition of the different chess pieces, and reduces the chances of confusing the chess pieces with one another as might occur if all pieces were the same height. 
     Additionally, the portable chess set of the invention places a relatively tall (and consequently strong) magnet within each of the chess pieces, and places a square array of ferro-magnetic objects (such as steel ball bearings) under the playing surface, one ferro-magnetic object centered in each square of the chess board. This allows for use of a relatively thin base, thereby reducing material cost, reducing the size and weight of the set, and making the set more portable. 
     A general aspect of the invention is a portable chess set able to preserve positions of chess pieces on a chess board during temporary interruption of game play, thereby permitting transportation of the chess board and then resuming game play. The portable chess set includes: a chess board having a playing surface partitioned into a plurality of square areas, each square area having a square center; a plurality of ferro-magnetic elements, each square area having a ferro-magnetic element embedded under the playing surface at the square center; a plurality of chess pieces; a plurality of magnets, each chess piece having a magnet embedded in a bottom center portion of the chess piece; and a chess piece position preserver including a planar member having a plurality of holes arranged as a square array, each hole having a hole center, each hole center configured to substantially align with a square center when the chess piece position preserver is secured in place over the chess board. 
     In some embodiments, each hole of the chess piece position preserver has a chamfered circumferential edge. 
     In some embodiments, the chess board is incorporated into a base assembly, and the chess piece position preserver is incorporated into a lid assembly, the base assembly and the lid assembly each having cooperative alignment features that are configured to engage so as to ensure that each hole center substantially aligns with a respective square center when the lid assembly is placed on top of the base assembly so as to engage the cooperative alignment features. 
     In some embodiments, the plurality of chess pieces are of different heights. 
     In some embodiments, the chess piece position preserver is made of a transparent material. 
     In some embodiments, cooperative alignment features of the base assembly and the lid assembly are also configured to engage so as to ensure that the lid assembly remains engaged with the base assembly until intentionally disengaged prior to resuming game play. In further embodiments, each of the cooperative alignment features include either a magnet or a ferro-magnetic element. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be more fully understood from the following Detailed Description, in conjunction with the following figures, wherein: 
         FIG. 1  is a perspective view of an embodiment of a portable chess set according to the invention, showing a lid assembly resting on top of a base assembly, the lid assembly including a chess piece position preserver having an array of holes, the base assembly supporting a chess board with a full set of chess pieces, the tops of the chess pieces extending up through the holes. 
         FIG. 2  is a top view of the portable chess set of  FIG. 1 , showing the array of holes of the chess piece position preserver, some holes showing a top view of a chess piece, some holes showing the absence of a chess piece (the alternating square colors of the chess board are not shown). 
         FIG. 3  is a cut-away side view of the portable chess set of  FIG. 1 , showing the lid assembly resting on top of the base assembly, a line of chess pieces extending up through a line of corresponding holes in the chess piece position preserver, and showing each chess piece having a magnet in its base that is attracted to a ball bearing of ferro-magnetic material embedded in the center area of each square of the chess board. 
         FIG. 4  is a close-up cut-away side view showing a single chess piece extending up through a hole in the chess piece position preserver, and showing the chess piece having a magnet in its base that is attracted to a ball bearing of ferro-magnetic material embedded in the center area of the underlying square of the chess board. 
         FIG. 5  is a perspective view of the base assembly, showing an array of squares of the chess board (omitting the alternating colors of the squares), also showing in dotted line an embedded sphere (or cylinder) of ferro-magnetic material in the center area of each square under the playing surface of the chess board. 
         FIG. 6  is a cut-away side view of the base assembly of  FIG. 5 , showing an embedded sphere (or cylinder) of ferro-magnetic material in the center area of each square under the playing surface of the chess board. 
         FIG. 7  is a side view with a partial cut-away side view of the base assembly of  FIG. 5 , again showing an embedded sphere (or cylinder) of ferro-magnetic material in the center area of each square under the playing surface of the chess board, also showing a plurality of chess pieces, each chess piece having a magnet centrally located towards the bottom of each chess piece. 
         FIG. 8  is a perspective view of an embodiment of the portable chess set of  FIG. 1 , showing chess pieces arranged after some game play, just before the lid assembly is placed on top of the base assembly so that the chess piece position preserver can preserve the positions of chess pieces during a pause in game play to permit transportation and continuation of the chess game. 
     
    
    
     DETAILED DESCRIPTION 
     With reference to  FIG. 1 , an embodiment  100  of a portable chess set according to the invention, showing a lid assembly  102  resting on top of a base assembly  104 , the lid assembly  102  including a chess piece position preserver  106  having an array of holes  108 , the base assembly  104  supporting a chess board  110  along with a full set of chess pieces  112 , the tops of the chess pieces  112  extending up through the holes  108 . Also shown are snap elements  114  that engage so as to removably attach the lid assembly  102  to the base assembly  104 . In other embodiments, a pair of magnets is used instead of the snap elements  114 , each magnet of the pair of magnets being attracted to the other magnet. 
     Referring to  FIG. 2 , the array of holes  108  of the chess piece position preserver  106 , some holes  108 ′ showing a top view of a chess piece, some holes  108  showing the absence of a chess piece (the alternating square colors of the chess board  110  are not shown). 
     With reference to  FIG. 3 , the lid assembly  102  rests on top of the base assembly  104 , a line of chess pieces  112  extends up through a line of corresponding holes  108  in the chess piece position preserver  106 . Also shown here is the magnet  300  in the base of each chess piece  112 . The magnet  300  is attracted to a ball bearing  302  made from a ferro-magnetic material that is embedded in the center area of each square (not shown) of the playing surface  304  of the chess board  110  of the base assembly  104 . 
     Referring to  FIG. 4 , a single chess piece  112  extends up through a hole  108  in the chess piece position preserver  106 . The chess piece  112  has a magnet  300  in its base that is attracted to a ball bearing  302  of ferro-magnetic material embedded in the center area of the underlying square of the playing surface  304  of the chess board  110  of the base assembly  104 . This provides a “snap-to-center” feature, which ensures that each chess piece  112  stays in the center of any given square  500  of the chess board  110 . This “snap-to-center” feature provides two benefits: it keeps the pieces  112  on the chess board  110  looking neat and orderly, and it ensures that the chess pieces  112  can all easily be “captured” by the chess piece position preserver  106  when it is put in place so as to preserve the positions of the chess pieces  112  during a pause in game play to permit transportation and continuation of the chess game. 
     Notice that the hole  108  shows a rounded or chamfered edge  400  so as to more easily fit over chess pieces  112  that may not be perfectly centered when the chess piece position preserver  106  is lowered over all of the chess pieces  112  on the chess board  110  when game play is to be paused prior to transport of the chess set  100 . 
     With reference to  FIG. 5 , the base assembly  104  is shown having an array of squares  500  of the chess board  110  (omitting the alternating colors of the squares), also showing in dotted line an embedded sphere  302  (or cylinder) of ferro-magnetic material in the center area of each square  500  under the playing surface  304  of the chess board  110  (which is just the aggregate of all the squares  500 ). 
     Referring to  FIG. 6 , an array of embedded spheres  302  (or cylinder) of ferro-magnetic material in the center area of each square (not shown) under the playing surface  304  of the chess board  110  is shown. 
     With reference to  FIG. 7 , the base assembly  104  is shown with a plurality of chess pieces  112  resting on the playing surface  304  of the chess board  110 , again showing an embedded sphere  302  (or cylinder) of ferro-magnetic material in the center area of each square  500  under the playing surface  304  of the chess board  110 , also showing a plurality of chess pieces, each chess piece having a magnet  300  centrally located towards the bottom of each chess piece. It is the attraction of the magnet  300  to the embedded sphere  302  that keeps the chess piece  112  securely on the board, while also keeping the chess piece  112  substantially centered within the square  500 . This will make placing the chess piece position preserver  106  over all of the chess pieces on the chess board  110  easier, such that the top portion of each chess piece  112  projects upward and through each hole  108  of the chess piece position preserver  106 . 
     Referring to  FIG. 8 , the chess pieces  112  are arranged after some game play, just before the lid assembly  102  is placed on top of the base assembly  104  so that the chess piece position preserver  106  can preserve the positions of chess pieces  112  during a pause in game play to permit transportation and continuation of the chess game. Note that snap elements  114  are shown before engaging so as to removably attach the lid assembly  102  to the base assembly  104 . 
     The portable chess set of the invention includes a standard number of chess pieces and a chess board. The portable chess set includes two pluralities of chess pieces, one plurality for each player, such as a plurality of white pieces and a plurality of black pieces. When the lid assembly  102  engages with the base assembly  104 , a piece position preserver  106  having a plurality of circular openings  108 , one opening  108  for each space on the chess board  110 , fits over any pieces  112  in play on the chess board  110 , and keeps them securely in place during transport. 
     One advantage of the portable chess set  100  of the invention is that it is self-contained and can be easily converted between a playable and transport configuration. It also provides an aesthetically pleasing product with no unsightly hinges or folds interrupting the play surface  304  of the chess board  110 . When in a playable configuration, the chess set  100  provides a stable surface for game play. 
     Each chess piece  112  has a magnet  300  incorporated within its base with, such as a bar magnet or cylindrical magnet vertically oriented. Each square  500  on the chess board  110  includes a ferromagnetic metal element  302  centered in the square  500 , such as a steel or iron ball bearing, or a cylinder with a height and diameter substantially equal. The attraction between the magnet  300  in the chess piece  112  and the ferro-magnetic metal sphere  302  ensures that each chess piece  112  can be securely but removably fastened to the square  500 , and ensures that each chess piece placed on a square  500  will be centered on that square  500 . 
     In other embodiments, a magnet oriented so as to attract the magnet in each chess piece can be embedded in the center area of each square of the chess board. This embodiment would provide stronger attraction between each chess piece and the squares of the chess board, thereby reducing movement or dislodgement of the chess pieces during storage or transport of the chess set. 
     A cover is provided with two planar components and four sides. The top planar component is a clear piece of plastic or glass that forms a protective barrier for the board and pieces. The inner planar component  106  has an array of holes  108  such that a center of each hole  108  aligns over the center of each square  500  of the chess board  110  when the cover is attached. The holes  108  are of sufficient diameter to allow each piece  112 , located at any square  500 , to pass through. Nevertheless, the holes  108  are small enough to constrain the lateral movement of each of the chess pieces  112  so as to prevent accidental dislodgment or movement during transport or storage. Thus, each hole  108  surrounds each chess piece  112  on the board  110  so as to prevent each chess piece  112  from moving laterally along the chess board  110 , while the magnetic attraction of each chess piece  112  on the board  110  to a magnet or ferromagnetic object  302  embedded in the board  110  substantially prevents vertical movement away from the chess board  110 . 
     The piece position preserver  106  has a plurality of circular openings  108 . The openings  108  preserve piece positions while allowing the typical variations in piece height, since the piece position preserver  106  retains the pieces from “waist level” of each chess piece. Accordingly, the upper portions of each chess piece must all fit within the diameter of the holes  108  in the piece position preserver  106 . Consequently, the shape of the Knight chess piece needs to be modified from what is conventional. Specifically, the head of the horse of the Knight (specifically the snout portion), extends outward asymmetrically from the central axis of the Knight. The snout must be shortened so as to fit through each of the holes  108 , while still retaining a sense of the classic “horse head” design of the Knight chess piece. 
     The portable chess set can be constructed of machined aluminum, machined acrylic sheet, polycarbonate back-printed label (for the playing surface) and various stainless steel fasteners. 
     In an embodiment of the present invention, injection molding is used to make some or all the components out of plastic. This would provide a lower cost and possibly faster method of manufacture as well as provide a lighter embodiment. 
     Other modifications and implementations will occur to those skilled in the art without departing from the spirit and the scope of the invention as claimed. Accordingly, the above description is not intended to limit the invention, except as indicated in the following claims.