CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This Application is a divisional of application Ser. No. 13/608,908, filed on Sep. 10, 2012, which is a continuation of application Ser. No. 13/339,041, filed on Dec. 28, 2011, now U.S. Pat. No. 8,272,337, issued on Sep. 25, 2012, which is a divisional of application Ser. No. 12/395,450, filed on Feb. 27, 2009, now U.S. Pat. No. 8,096,246, issued on Jan. 17, 2012, which is a divisional of application Ser. No. 11/444,154, filed on May 31, 2006, now U.S. Pat. No. 7,503,266, issued on Mar. 17, 2009, incorporated by reference in their entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    This invention relates generally to folding, collapsible structures, and more particularly relates to a modular folding table having a truss framework, a folding table top and a folding utility shelf. 
         [0003]    Folding card tables and heavy work tables having individual legs or pairs of legs that are pivotally connected to a table top to swing down from a concealed position to lock into a set up position are well known. The portability of such tables is generally limited by the size of the table top. The lighter card table style tables are generally not strong enough or stable enough to support modern video or computer types of displays that are currently used in traveling presentations. The heavier, folding work style tables are generally quite large and heavy, making them impractical for use as a portable display table in presentations, often requiring the use of a truck for transporting video or computer display equipment and appropriate display tables. A display table offering one or more utility shelves would also be useful for providing an efficient use of space for display equipment, but conventional tables providing one or more utility shelves have also generally not been collapsible and easily portable. 
         [0004]    In order to provide such a collapsible display table that is expandable both horizontally as well as vertically, it would be desirable to provide a modular folding table with a collapsible truss framework that supports a folding table top and a folding utility shelf to offer a larger and more efficient use of table space, and having improved strength and stability, to support relatively large, heavy equipment and displays such as video display monitors, video or film display equipment, and the like. The present invention fulfills these needs. 
       SUMMARY OF THE INVENTION 
       [0005]    Briefly and in general terms, the present invention provides for a modular folding table with a collapsible truss framework that supports a folding table top and a folding utility shelf, with the truss framework connected to a plurality of legs that can be connected horizontally or vertically to the legs of one or more similar modular folding tables, to provide desired table and shelf space with a structure that is foldable, strong and stable. 
         [0006]    The present invention accordingly provides for a modular folding table, including a plurality of vertically disposed legs, each of the legs having an upper end and a lower end, and a truss framework connected to each of the legs. The truss framework includes a plurality of truss pairs of link members, each of the truss pairs including first and second link members having upper and lower ends. The first and second link members are pivotally connected together at a midpoint between the upper and lower ends, the first end of the first link member is pivotally connected to the upper end of one of the legs, and the second end of the first link member is slidably connected to an adjacent one of the legs. The first end of the second link member is similarly pivotally connected to the upper end of one of the legs, the second end of the first link member is slidably connected to an adjacent one of the legs, and the first and second link members are pivotally connected together in a scissors configuration so as to be extendable horizontally from a collapsed configuration to an extended configuration. Each of the first and second link members advantageously includes a table top support bracket mounted between the midpoint and the upper ends of the link members. A plurality of slider members are slidably mounted to each of the plurality of vertically disposed legs, respectively, and the second ends of the link members are connected to corresponding slider members, respectively, for slidably connecting adjacent second link members of adjacent sides to corresponding vertically disposed legs, respectively. A table top is removably disposed on the upper ends of the legs and rests on the table top support brackets of the truss pairs of link members in the extended configuration. 
         [0007]    In one presently preferred aspect, the upper ends of the legs include a land for supporting the table top, and the upper ends of the legs include a recess for receiving a lower end of a leg of a second modular folding table for vertically stacking the second modular folding table on the modular folding table. In another presently preferred aspect, an upper leg connector bracket is provided for connecting one the recess of one of the legs of the modular folding table to an adjacent recess in an upper end of a leg of a second modular folding table for horizontally connecting the modular folding table and the second modular folding table together. A lower leg connector bracket may also be provided for connecting one of the legs of the modular folding table to an adjacent leg of a second modular folding table for horizontally connecting the modular folding table and the second modular folding table together. A latch may also be provided for latching at least one of the slider members in a fixed position on at least one of the legs. 
         [0008]    In another presently preferred aspect, each of the legs further includes a telescoping foot extension, and the legs may include means for fixing the foot extension in a retracted position or in an extended position. The upper ends of the legs along at least one side of the modular folding table may also include a socket for receiving a table top support bar. A second modular folding table may also be provided, wherein the upper ends of the legs along at least one side of the second modular folding table include a land for supporting the second table top and a socket for receiving the table top support bar. In another presently preferred aspect, the table top includes a plurality of segments connected together by at least one hinge, so as to be foldable. In another presently preferred aspect, the table top comprises at least three segments connected together by at least two hinges each including a pair of flat plate portions connected to adjoining segments of the table top, the pair of flat plate portions being pivotally connected together by a pivot pin, and the at least two hinges having the flat plate portions connected to the pivot pin at positions at different distances from the flat plate portions so that the table top is foldable. In another presently preferred aspect, the table top includes a plurality of notches at corner locations corresponding to the plurality of legs when the legs and the truss framework are in the extended configuration. 
         [0009]    In another presently preferred aspect, the modular folding table includes at least two shelf support arms each having first and second ends, and means for removably attaching the first and second ends between adjacent legs for supporting a lower shelf, which may be disposed on the at least two shelf support arms. In another presently preferred aspect, the lower shelf includes a plurality of segments hingedly connected together so as to be foldable. The lower shelf may, for example, include at least three segments connected together by at least two hinges, the at least two hinges each including a pair of flat plate portions connected to adjoining segments of the lower shelf, the pair of flat plate portions being pivotally connected together by a pivot pin, and the at least two hinges having the flat plate portions connected to the pivot pin at positions at different distances from the flat plate portions, so that the lower shelf is foldable. In another presently preferred aspect, the lower shelf includes a plurality of notches at corner locations corresponding to the plurality of legs when the legs and the truss framework are in the extended configuration. 
         [0010]    Other features and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments in conjunction with the accompanying drawings, which illustrate, by way of example, the operation of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a perspective view of a first embodiment of the modular folding table in a disassembled, collapsed configuration according to the present invention. 
           [0012]      FIG. 2  is a perspective view of the modular folding table of  FIG. 1  in an extended configuration prior to assembly with the table top. 
           [0013]      FIG. 3  is a perspective view of the modular folding table of  FIG. 1  in an assembled, extended configuration. 
           [0014]      FIG. 4  is a perspective view of the modular folding table of  FIG. 1  in an extended configuration with the legs extended, prior to assembly with the table top. 
           [0015]      FIG. 5  is a perspective view of the underside of the table top and upper end of a leg of the modular folding table of  FIG. 1 . 
           [0016]      FIG. 6  is a perspective view of the upper end of a leg of the modular folding table of  FIG. 1 . 
           [0017]      FIG. 7  is a perspective view of a corner of the upper side of the table top and upper end of a leg of the modular folding table of  FIG. 1 . 
           [0018]      FIG. 8  is a perspective view of the underside of the table top showing the hinges of the table top of  FIG. 1 . 
           [0019]      FIG. 9  is a perspective view of the underside of the table top illustrating the folding of the table top of  FIG. 1 . 
           [0020]      FIG. 10  is a perspective view of the modular folding table of  FIG. 1  in an assembled, extended configuration, with shelf support arms added. 
           [0021]      FIG. 11  is a perspective view of the modular folding table of  FIG. 1  in an extended configuration, with shelf support arms added, prior to assembly with the table top. 
           [0022]      FIG. 12  is a perspective view of a shelf support bracket mounted to a leg of the modular folding table of  FIG. 1 . 
           [0023]      FIG. 13  is another perspective view of a shelf support bracket mounted to a leg of the modular folding table of  FIG. 1 . 
           [0024]      FIG. 14  is a perspective view of the modular folding table of  FIG. 1  horizontally connected to a second modular folding table by a lower leg connector bracket. 
           [0025]      FIG. 15  is a perspective view of the upper end of a leg of the modular folding table of  FIG. 1  placed adjacent to the upper end of a leg of a second modular folding table showing the placement of the upper recesses of the adjacent legs together. 
           [0026]      FIG. 16  is a perspective view of the upper ends of the legs of the first and second modular folding tables of  FIG. 15  horizontally connected together with an upper leg connecting bracket connecting the upper recesses of the adjacent legs together. 
           [0027]      FIG. 17  is a perspective view of the lower end of a leg of the modular folding table of  FIG. 1  placed adjacent to the lower end of a leg of a second modular folding table. 
           [0028]      FIG. 18  is a perspective view of the lower ends of the legs of the first and second modular folding tables of  FIG. 17  with a lower leg connecting bracket connecting the lower legs together. 
           [0029]      FIG. 19  is a perspective view of a second embodiment of the modular folding table in a disassembled, extended configuration, prior to assembly with a table top, according to the present invention. 
           [0030]      FIG. 20  is an enlarged view of an upper leg of the modular folding table of  FIG. 19 , showing the upper leg pivotally connected to the upper ends of three link members of the truss framework, and a slider mounted on the leg pivotally connected to the lower ends of three link member of the truss framework. 
           [0031]      FIG. 21  is a perspective view of the modular folding table of  FIG. 19  in an assembled, extended configuration. 
           [0032]      FIG. 22  is a perspective view of the modular folding table of  FIG. 19  in an assembled, extended configuration, and connected by upper and lower leg connector brackets to a second modular folding table. 
           [0033]      FIG. 23  is a perspective view of a third embodiment of the modular folding table including table top support bars, shown in an assembled, extended configuration, with a variant of the second embodiment connected by table top support bars to a second modular folding table, which is a variant of the first embodiment, including shelf support arms. 
           [0034]      FIG. 24  is another perspective view of the modular folding table of  FIG. 23 . 
           [0035]      FIG. 25  is a perspective view of the modular folding table of  FIG. 23 , including a lower shelf installed on shelf support arms. 
           [0036]      FIG. 26  is another perspective view of the modular folding table of  FIG. 23 , showing a table top placed on the table top support bars. 
           [0037]      FIG. 27  is a perspective view of an underside of a table top and an upper end of a leg of the modular folding table of  FIG. 26 , showing a socket for receiving a table top support bar. 
           [0038]      FIG. 28  is another perspective view of a table top and an upper end of a leg of the modular folding table of  FIG. 26 , showing a socket for receiving a table top support bar. 
           [0039]      FIG. 29  is a perspective view of a lower modular folding table of  FIG. 1  with a second modular folding table vertically stacked on top, with the legs of the second modular folding table connected in the upper recesses of the legs of the lower modular folding table. 
           [0040]      FIG. 30  is a perspective view of a lower modular folding table of  FIG. 19  with a second modular folding table vertically stacked on top, with the legs of the second modular folding table connected in a portion of the upper recesses of the legs of the lower modular folding table. 
           [0041]      FIG. 31  is an enlarged view of a portion of the view of  FIG. 30 , showing the lower modular folding table of  FIG. 19  with a second modular folding table vertically stacked on top, with the legs of the second modular folding table connected in a portion of the upper recesses of the legs of the lower modular folding table. 
           [0042]      FIG. 32  is a perspective view of a lower modular folding table of  FIG. 19  with a second modular folding table vertically stacked on top, with the legs of the second modular folding table connected in a portion of the upper recesses of the legs of the lower modular folding table, with a lower shelf mounted on lower shelf support arms of the upper, second modular folding table. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0043]    Referring to the drawings, which are provided for purposes of illustration and by way of example, the present invention provides for a modular folding table  20 , including a plurality of legs  22 , and a truss framework  24  connected to each of the legs, shown in a disassembled, collapsed configuration in  FIG. 1 . As is shown in  FIG. 2 , the truss framework includes a plurality of truss pairs of link members  26 , with each of the truss pairs including first link members  28  and second link members  30 , each having upper ends  32  and lower ends  34 . A table top  38 , shown in  FIGS. 1 and 3 , can be removably disposed on the upper ends of the legs. The first and second link members are pivotally connected together at a midpoint  36  between the upper and lower ends in a scissors configuration so as to be extendable horizontally from a collapsed configuration to an extended configuration. Referring to  FIGS. 2 and 3 , in a presently preferred aspect, each of the first and second link members also includes a table top support bracket  39  mounted between the midpoint and the upper ends of the link members for contacting and supporting the table top when it is placed on the upper ends of the legs. 
         [0044]    Each of the legs has an upper end  40  and a lower end  42 , and the upper end of the first link member is pivotally connected to the upper end of one of the legs, and the lower end of the first link member is slidably connected to an adjacent one of the legs. Likewise, the upper end of the second link member is pivotally connected to the upper end of one of the legs, and the lower end of the first link member is slidably connected to an adjacent one of the legs. 
         [0045]    With reference to  FIGS. 6 and 7 , in a presently preferred aspect, the upper ends of the legs include a land  44  for supporting the table top. In another presently preferred aspect, the upper ends of the legs include a recess  46  for receiving a lower end of a leg  22 ′ of a second modular folding table  20 ′, for stacking the second modular folding table on the modular folding table, as is illustrated in  FIG. 29 , or for horizontally connecting an adjacent second modular folding table  20 ′, as is illustrated in  FIG. 14 , described further below. 
         [0046]    Referring to  FIG. 5 , each the leg preferably includes a slider member  50  slidably mounted to the leg for slidably connecting the lower ends of the first and second link members to corresponding ones of the legs. As is illustrated in  FIG. 6 , in a presently preferred aspect, at least one of the legs includes latch means  54  for latching at least one of the slider members in a fixed position on the leg. Referring to  FIGS. 2 and 4 , each of the legs preferably includes a telescoping foot extension  56 , and each of the legs preferably includes means  58  for fixing the foot extension in a retracted position and for fixing the foot extension in an extended position, such as spring loaded detent pins and corresponding latching holes in the leg, for example. 
         [0047]    As is shown in  FIGS. 8 and 9 , the table top comprises a plurality of segments  72   a,    72   b ,  72   c,  connected together by at least one hinge  74  so that the table top segments are foldable. Typically, the table top comprises at least three segments connected together by at least two hinges,  74   a,    74   b,  each of which includes a pair of flat plate portions  76  connected to adjoining segments of the table top. The pair of flat plate portions of each hinge are pivotally connected together by a pivot pin  78 , and preferably the flat plate portions of at least one of the hinges are connected to the pivot pin by right angle members  80   a,    80   b  extending transversely from the flat plat portions, so that the table top segments are foldable. In another presently preferred aspect, shown in  FIGS. 7 and 9 , for example, the table top includes a plurality of notches  82  at corner locations corresponding to the plurality of legs when the legs and the truss framework are in the extended configuration. 
         [0048]    Referring to  FIGS. 10-13 , in another presently preferred aspect, the modular folding table may be provided with at least two shelf support arms  84  each having a first end  86  and a second end  88  connected between a pair of legs, so that a lower shelf  90 , shown in  FIG. 11 , may thus be removably disposed on the shelf support arms. The lower shelf typically includes a plurality of segments hingedly connected together so as to be foldable, such as at least three segments  92   a,    92   b,    92   c  connected together by at least two hinges, for example. The hinges of the shelf typically also each include a pair of flat plate portions connected to adjoining segments of the lower shelf, and the pair of flat plate portions are pivotally connected together by a pivot pin  98 . Preferably the flat plate portions of at least one of the hinges are connected to the pivot pin by right angle members  100   a,    100   b  extending transversely from the flat portions, so that the lower shelf segments are foldable. In another preferred aspect, the lower shelf includes a plurality of notches  102  at corner locations corresponding to the plurality of legs when the legs and the truss framework are in the extended configuration. 
         [0049]    Referring to  FIGS. 14-16 , an upper leg connector bracket  48 , such as a two plug cap, for example, may also be provided for connecting a recess  46  of one of the legs of the modular folding table to an adjacent recess  46 ′ in an upper end  40 ′ of a leg  22 ′ of a second modular folding table  20 ′ for connecting the modular folding table  20  and the second modular folding table  20 ′ together. As is illustrated in  FIGS. 14 ,  17  and  18 , a lower leg connector bracket  52 , such as a two plug cap, for example, may also be provided for connecting sockets  51  of female connector brackets  53  attached to the lower leg portions may also be provided for connecting one of the legs  22  of the modular folding table to an adjacent leg  22 ′ of a second modular folding table  20 ′ for connecting the modular folding table and the second modular folding table together. 
         [0050]    Referring to  FIGS. 19-21 , in which like reference numbers denote like elements, in a second embodiment of the modular folding table according to the present invention, the modular folding table  120  includes a plurality of legs  122 , and a truss framework  124  connected to each of the legs. The truss framework includes a plurality of truss pairs of link members  126 , with each of the truss pairs including first link members  128  and second link members  130 , each having upper ends  132  and lower ends  134 . A plurality of table tops  138  can be removably disposed on the upper ends of the legs. The first and second link members are pivotally connected together at a midpoint  136  between the upper and lower ends in a scissors configuration so as to be extendable horizontally from a collapsed configuration to an extended configuration. Each of the first and second link members includes a table top support bracket  139  mounted between the midpoint and the upper ends of the link members for contacting and supporting the table top when it is placed on the upper ends of the legs. 
         [0051]    Each of the legs has an upper end  140  and a lower end  142 , and the upper end of the first link member is pivotally connected to the upper end of one of the legs, and the lower end of the first link member is slidably connected to an adjacent one of the legs. Likewise, the upper end of the second link member is pivotally connected to the upper end of one of the legs, and the lower end of the first link member is slidably connected to an adjacent one of the legs. 
         [0052]    The upper ends of the legs include a pair of lands  144  for supporting the plurality of table tops. Each leg preferably includes a slider member  150  slidably mounted to the leg for slidably connecting the lower ends of the first and second link members to corresponding ones of the legs. In a presently preferred aspect, at least one of the legs includes latch means for latching at least one of the slider members in a fixed position on the leg. Each of the legs preferably includes a telescoping foot extension, and each of the legs preferably includes means, such as a spring loaded detent pin and corresponding latching hole in the leg, for example, for fixing the foot extension in a retracted position, and means, such as another spring loaded detent pin and corresponding latching hole in the leg, for fixing the foot extension in an extended position. The table top preferably includes a plurality of notches  182  at corner locations corresponding to the plurality of legs when the legs and the truss framework are in the extended configuration. 
         [0053]    As is illustrated in  FIG. 22 , an upper leg connector bracket  148 , such as a two plug cap, for example, may also be provided for connecting a recess of one of the legs of the modular folding table to an adjacent recess in an upper end  140 ′ of a leg  122 ′ of a second modular folding table  120 ′ for connecting the modular folding table and the second modular folding table together. As is illustrated in  FIG. 22 , a lower leg connector bracket  152 , such as a two plug cap, for example, may also be provided for connecting sockets of female connector brackets  153  attached to the lower leg portions may also be provided for connecting one of the legs of the modular folding table to an adjacent leg  122 ′ of a second modular folding table  120 ′ for connecting the modular folding table and the second modular folding table together. In another presently preferred aspect, the upper ends of the legs include a recess  146  for receiving a lower end of a leg  122 ′ of a second modular folding table  120 ′, for stacking the second modular folding table on the modular folding table, as is illustrated in  FIGS. 30-32 . 
         [0054]    As described above, in another presently preferred aspect, the modular folding table may be provided with shelf support arms connected between a pair of legs, so that a lower shelf may thus be removably disposed on the shelf support arms. The lower shelf typically includes a plurality of segments hingedly connected together so as to be foldable, such as at least three segments connected together by at least two hinges, for example. The hinges of the shelf typically also each include a pair of flat plate portions connected to adjoining segments of the lower shelf, and the pair of flat plate portions are pivotally connected together by a pivot pin. Preferably the flat plate portions of at least one of the hinges are connected to the pivot pin by right angle members extending transversely from the flat portions, so that the lower shelf segments are foldable. In another preferred aspect, the lower shelf includes a plurality of notches at corner locations corresponding to the plurality of legs when the legs and the truss framework are in the extended configuration. 
         [0055]    In a third preferred embodiment, in which like reference numbers denote like elements, as is illustrated in  FIGS. 23-28 , the invention provides for a modular folding table  220  including a plurality of legs  222 , and a truss framework  224  connected to each of the legs. The truss framework includes a plurality of truss pairs of link members  226 , with each of the truss pairs including first link members  228  and second link members  230 , each having upper ends  232  and lower ends  234 . A plurality of table tops  238  can be removably disposed on the upper ends of the legs. The first and second link members are pivotally connected together at a midpoint  236  between the upper and lower ends in a scissors configuration so as to be extendable horizontally from a collapsed configuration to an extended configuration. Each of the first and second link members includes a table top support bracket  239  mounted between the midpoint and the upper ends of the link members for contacting and supporting the table top when it is placed on the upper ends of the legs. 
         [0056]    Each of the legs has an upper end  240  and a lower end  242 , and the upper end of the first link member is pivotally connected to the upper end of one of the legs, and the lower end of the first link member is slidably connected to an adjacent one of the legs. Likewise, the upper end of the second link member is pivotally connected to the upper end of one of the legs, and the lower end of the first link member is slidably connected to an adjacent one of the legs. 
         [0057]    The upper ends of the legs include a pair of lands  244  for supporting the plurality of table tops. Each leg preferably includes a slider member  250  slidably mounted to the leg for slidably connecting the lower ends of the first and second link members to corresponding ones of the legs. As described above, in a presently preferred aspect, at least one of the legs includes latch means for latching at least one of the slider members in a fixed position on the leg. Each of the legs preferably includes a telescoping foot extension, and each of the legs preferably includes means, such as a spring loaded detent pin and corresponding latching hole in the leg, for example, for fixing the foot extension in a retracted position, and means, such as another spring loaded detent pin and corresponding latching hole in the leg, for fixing the foot extension in an extended position. The table top preferably includes a plurality of notches  282  at corner locations corresponding to the plurality of legs when the legs and the truss framework are in the extended configuration. 
         [0058]    The upper ends  240  of the legs  222  along at least one side  262  of the modular folding table, and preferably along opposing sides, include a land  264  for supporting a table top, and a socket  266  for receiving a table top support bar  268  for supporting the table top, as is illustrated in  FIG. 26 , for example. 
         [0059]    Referring to  FIGS. 23-26 , in another presently preferred aspect, the modular folding table may be provided with at least two shelf support arms  284  each having a first end and a second end connected between a pair of legs, so that a lower shelf  290  may thus be removably disposed on the shelf support arms. The lower shelf typically includes a plurality of segments hingedly connected together so as to be foldable, such as at least three segments connected together by at least two hinges, for example. The hinges of the shelf typically also each include a pair of flat plate portions connected to adjoining segments of the lower shelf, and the pair of flat plate portions are pivotally connected together by a pivot pin. Preferably the flat plate portions of at least one of the hinges are connected to the pivot pin by right angle members extending transversely from the flat portions, so that the lower shelf segments are foldable. In another preferred aspect, the lower shelf includes a plurality of notches at corner locations corresponding to the plurality of legs when the legs and the truss framework are in the extended configuration. 
         [0060]    It will be appreciated that the present invention accordingly provides for a modular folding table with one or more braces added to the truss framework for supporting a table top, with legs having upper portions with recesses for receiving the legs of one or more other modular tables, so that the modular folding table of the invention is stackable. The present invention also provides for a modular folding table with brackets allowing the addition of one or more leaves of a table top to expand the table without adding base frame sections. In addition, shelves can be fixed to the legs with brackets, and the modular folding table of the invention is connectable at the base of the legs by brackets that allow two or more tables to connect with a two plug cap. 
         [0061]    It will be apparent from the foregoing that, while particular forms of the invention have been illustrated and described, various modifications can be made without departing from the spirit and scope of the invention. Accordingly, it is not intended that the invention be limited, except as by the appended claims.
The modular folding table includes a collapsible truss framework that supports a folding table top and a folding utility shelf, and includes legs that can be connected horizontally or vertically to the legs of one or more similar modular folding tables, to provide desired table and shelf space with a structure that is foldable, strong and stable.