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FIELD 
     The present invention is directed toward the field of horizontal spacers for glass blocks. In particular, the present invention relates to horizontal spacers for positioning on rectangular and non-rectangular glass blocks, which enables non-rectangular glass blocks to be connected to adjacent non-rectangular or rectangular glass blocks such that any configuration of wall may be formed using such blocks. 
     BACKGROUND OF THE INVENTION 
     Glass blocks are widely used in modern architecture and in the construction industry for building things such as walls, partitions and shower walls. For rectangular glass blocks, the interface surface between vertical stacks of such blocks is rectangular. The interface surface for non-rectangular glass blocks have edges which form angles of 22½ degrees, 45 degrees, 90 degrees, and radius blocks having curved outer surfaces. Rectangular and non-rectangular glass blocks have a raised peripheral flange formed around the external faces of the block and an intermediate raised peripheral flange disposed proximate the midpoint of the internal periphery of the glass block. 
     When assembling a glass block wall with mortar a high degree of skill is required, as the weight of the blocks on the mortar make it difficult to obtain evenly spaced horizontal or vertical course arrangements between each row of blocks. Also, the blocks tend to be non-porous and as a result do not form a strong bond with the mortar. In order to solve these problems, many glass block assemblies exist which use generally rigid spacing, reinforcement and tying devices for the blocks. However, many of these assemblies have a large number of parts, and/or require a skilled laborer to assemble the glass block wall. 
     As a consequence, there is a need for a horizontal spacer for non-rectangular glass blocks that not only enables the same size joints to be easily obtained, but also allows the joints to be adjusted. Further, there is a need for a horizontal spacer for non-rectangular glass blocks that has a minimal number of parts such that the glass block wall may be constructed quickly and easily by an unskilled laborer, thereby reducing the cost. Accordingly, it is an object of the invention to provide a horizontal spacer for positioning on rectangular or non-rectangular glass blocks, which may connect to an adjacent horizontal spacer from the present invention or with a rectangular glass block horizontal spacer. 
     SUMMARY OF THE INVENTION 
     The present invention provides a horizontal spacer for positioning on rectangular and non-rectangular glass blocks, which enables a connection to a spacer on an adjacent non-rectangular or rectangular glass block. The horizontal spacer comprises a generally planar main portion that is positioned between the peripheral edges of the top and/or bottom surfaces of the non-rectangular glass block and tabs, which extend in the plane of and extending from opposing sides of the main portions. Receiving holes are also located on opposing sides of the main portion. The tabs connect to other non-rectangular horizontal spacers by inserting the tabs into the receiving holes of the adjacent horizontal spacer. The tabs can also connect to a rectangular horizontal spacer by inserting the tabs directly into the spacer. The tabs extend perpendicularly from an edge of the main portion enabling a square connection to be made to an adjacent non-rectangular or rectangular horizontal spacer, such that any configuration of angled or curved glass wall can be installed with a reduced amount of time and effort. Further, the tabs allow for the spacing between the joints to be varied as well as for minor lateral adjustments. 
     The horizontal spacer preferably consists of two identical pieces. The main portion of each piece has holes and pegs, which connect the identical pieces together. Preferably, the tabs on one side of the main portion are diagonally opposite from the tabs on the other side, as are the receiving holes. Therefore, as the tabs are offset, two tabs and two receiving holes are located on opposing sides. Advantageously, parts are minimized as one piece of the horizontal spacer may be used for the first and last row, where a spacer of lesser thickness is required. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Further features and advantages of the invention will be apparent from the following detailed description, given by way of example, of a preferred embodiment taken in conjunction with the accompanying drawings, wherein: 
     FIG. 1 is a perspective view of the horizontal spacer for use with radius glass blocks; 
     FIG. 2 is a perspective view of one half of the horizontal spacer for use with radius glass blocks; 
     FIG. 3 is a perspective view of a section of glass block wall constructed in accordance with the teachings of this invention using the horizontal spacer for radius glass blocks; 
     FIG. 4 is a top view of the horizontal spacer for use with 90-degree glass blocks; 
     FIG. 5 is a perspective view of one half of the horizontal spacer for use with 90-degree glass blocks; 
     FIG. 6 is a perspective view of the horizontal spacer for use with 90-degree glass blocks in use with adjacent rectangular glass blocks; 
     FIG. 7 is a perspective view of the horizontal spacer for use with 45-degree glass blocks; 
     FIG. 8 is a perspective view of one half of the horizontal spacer for use with 45 degree glass blocks; and 
     FIG. 9 is a perspective view of the horizontal spacer for use with 45-degree glass blocks in use with adjacent rectangular glass blocks. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to FIG. 1, a perspective view of the horizontal spacer  18  for a radius glass block, such as the ARQUE® block by Pittsburgh-Corning Company, is shown. Two identical main pieces  24 A and  24 B connect together to form the horizontal spacer  18 . Each main piece  24 A and  24 B includes elongated tabs  20 A and  20 B and receiving holes  22 A and  22 B. Preferably, tabs  20 A and receiving holes  22 B are adjacent on one side of each of the main pieces  24 A and  24 B and tabs  20 B and receiving holes  22 A are adjacent on the opposing side of each of the main pieces  24 A and  24 B. The tabs  20 A and  20 B extend perpendicularly from the main pieces  24 A and  24 B such that a square connection can be made to adjacent horizontal spacers. The tabs  20 A and  20 B include barbs  26  that aid in fitting the tabs into corresponding receiving holes of other horizontal spacers of the system. The tabs  20 A and  20 B are insertably adjustable into the receiving holes of adjacent rectangular or non-rectangular horizontal spacers and allow the spacing between the joints of adjacent glass blocks to be varied. 
     Referring to FIG. 2, a perspective view of main piece  24 B of the horizontal spacer  18  having a radius shape is shown. Main pieces  24 A and  24 B each include pegs  28 A and holes  28 B, such that the pegs  28 A of piece  24 A connect to holes  28 B on piece  24 B to connect the pieces together to form the horizontal spacer  18  as shown in FIG.  1 . 
     Main pieces  24 A and  24 B may be used as the first or last row of spacers when constructing a glass block wall, where a spacer of lesser thickness is required. 
     Referring to FIG. 3 a perspective view of a glass block wall  10  is shown using radius horizontal spacers  18  with the radius blocks  14  and rectangular horizontal spacers  16  for straight blocks  12 . As shown in the drawing the main portion of the horizontal spacer  18  fits within the peripheral edges of the top of the radius glass block  14 . The type of glass blocks  12  used have a generally rectangular configuration with a raised peripheral flange formed around the external faces of the block and an intermediate raised peripheral flange disposed proximate the midpoint of the internal periphery of the glass block. Rectangular glass blocks are available in various sizes from various commercial sources such as Pittsburgh-Corning Company. 
     Referring to FIG. 4, a perspective view of the horizontal spacer  30  for a 90 degree glass block, such as the HEDRON® corner block by Pittsburgh-Corning Company is shown. Two identical main pieces  38 A and  38 B connect together to form the horizontal spacer. Each main piece  38 A and  38 B includes elongated tabs  32 A and  32 B and receiving holes  34 A and  34 B. Preferably, tabs  32 A and receiving holes  34 B are adjacent on one side of each of the main pieces  38 A and  38 B and tabs  32 B and receiving holes  34 A are adjacent and on the opposing side of each of main pieces  38 A and  38 B. The tabs  32 A and  32 B extend perpendicularly from the main pieces  38 A and  38 B such that a square connection can be made to adjacent horizontal spacers. The tabs  32 A and  32 B include barbs  36  that aid in fitting the tabs into corresponding receiving holes of other horizontal spacers of the system. The tabs  32 A and  32 B are insertably adjustable into the receiving holes of adjacent rectangular or non-rectangular horizontal spacers and allow the spacing between the joints of adjacent glass blocks to be varied. 
     Referring to FIG. 5, a perspective view of main piece  38 B of the horizontal spacer  30  having a 90 degree shape is shown. Main pieces  38 A and  38 B each include pegs  40 A and holes  40 B, such that the pegs  40 A of piece  38 A connect to holes  40 B on piece  38 B to connect the pieces together to form the horizontal spacer  30  as shown in FIG.  4 . 
     Main pieces  38 A and  38 B may be used as the first or last row of spacers when constructing a glass block wall, where a spacer of lesser thickness is required. 
     Referring to FIG. 6 a perspective view of a glass block wall  42  is shown using 90 degree horizontal spacer  30  with the 90 degree block  44  and rectangular horizontal spacers  16  for rectangular glass blocks  12 . As shown in the drawing the main portion of the horizontal spacer  30  fits within the peripheral edges of the top of the  90  degree glass block  44 . 
     Referring to FIG. 7, a perspective view of the horizontal spacer  46  for a 45 degree glass block, such as the TRIDRON® 45 degree block units by Pittsburgh-Corning Company is shown. Referring to FIG. 8 a perspective view of main piece  52 B of the horizontal spacer  46  for a 45 degree block. Referring to FIGS. 7 and 8, two identical main pieces  52 A and  52 B connect together to form the horizontal spacer  46 . Each main piece  52 A and  52 B includes elongated tabs  48 A and  48 B and receiving holes  50 A and  50 B. Preferably, tabs  48 A and receiving holes  50 B are adjacent on one side of each of the main pieces  52 A and  52 B and tabs  48 B and receiving holes  50 A are adjacent on the opposing side of each of main pieces  52 A and  52 B. The tabs  48 A and  48 B extend perpendicularly from the main pieces  52 A and  52 B such that a square connection can be made to adjacent horizontal spacers. The tabs  48 A and  48 B include barbs  56  that aid in fitting the tabs into corresponding receiving holes of other horizontal spacers of the system. The tabs  48 A and  48 B are insertably adjustable into the receiving holes of adjacent rectangular or non-rectangular horizontal spacers and allow the spacing between the joints of adjacent glass blocks to be varied. 
     Main pieces  52 A and  52 B each include pegs  54 A and holes  54 B, such that the pegs  54 A of piece  52 A connect to holes  54 B on piece  52 B to connect the pieces together to form the horizontal spacer  46  as shown in FIG.  7 . 
     Main pieces  52 A and  52 B may be used as the first or last row of spacers when constructing a glass block wall, where a spacer of lesser thickness is required. 
     Referring to FIG. 9 a perspective view of a glass block wall  56  is shown using a 45 degree horizontal spacer  46  with a 45 degree block  54  and rectangular horizontal spacers  16  for rectangular glass blocks  12 . As shown in the drawing the main portion of the horizontal spacer  18  fits within the peripheral edges of the top of the radius glass block  14 . 
     The three examples of horizontal spacers shown are radius, 45 degree, and 90 degree; however, any shape of horizontal spacer can be formed to accommodate any rectangular or non-rectangular glass block. Further, although two tabs and two receiving holes are described, more or less than two tabs or receiving holes may be used. 
     Accordingly, while this invention has been described with reference to illustrative embodiments, this description is not intended to be construed in a limiting sense. Various modifications of the illustrative embodiments, as well as other embodiments of the invention, will be apparent to persons skilled in the art upon reference to the description. It is therefore contemplated that the appended claims will cover any such modifications or embodiments as fall within the true scope of the invention.

Summary:
This application discloses a horizontal spacer for rectangular and non-rectangular glass blocks, which enables non-rectangular glass blocks to be connected to adjacent non-rectangular or rectangular glass blocks such that any configuration of wall may be formed using such blocks. The horizontal spacer has elongated tabs and receiving holes which extend from opposing sides. The elongated tabs engage the receiving holes of adjacent horizontal spacers.