Abstract:
A foldable tabletop easel with a pair of opposing support members rotatably connected in a vertical central joint, opposing pedestal members rotatably attached to the lower vertical portion of the outside edges of the respective support members and a positioning tab connected to one of the support members in a tab insert adjacent to the central joint. The positioning tab has slots which secure the easel in a display position as the positioning tab is rotated onto a tab rib in a tab insert in the other support member. The easel can be of unitary construction of cardboard.

Description:
FIELD OF THE INVENTION 
   This invention is in the field of devices for holding and displaying display items such as posters and books, and, in particular, is in the field of easels. 
   BACKGROUND OF THE INVENTION 
   Various devices are disclosed in the prior art for holding and displaying posters, works of art, photos, business charts, books and other display items for presentations, exhibitions and other purposes. Floor or table standing easels, commonly constructed of tubular and other structural components which may be of metal, plastic or other materials, or combinations thereof, have long been used for such applications. These devices are relatively expensive, bulky, heavy and not particularly easy to use. 
   A number of devices are also disclosed in the prior art which attempt to provide a less expensive, lighter, and less bulky means for holding and displaying such items. A number of such devices, particularly tabletop easels, have been designed to be constructed principally of corrugated paperboard or other types of cardboard or other lightweight, inexpensive materials and some have been designed to be more or less foldable, to make them less bulky for transport. 
   An object of the present invention is to provide an inexpensive, simple, stable tabletop easel which is foldable to a compact configuration for transport. 
   A further object of the present invention is to provide a tabletop easel that can be constructed of a unitary panel of corrugated paperboard or other types of cardboard or other common, inexpensive material. 
   SUMMARY OF THE INVENTION 
   A preferred embodiment of the easel of the present invention is comprised of a left support member, a right support member, a left pedestal member, a right pedestal member and a positioning tab. The left support member is rotatably connected to the right support member in a vertical central joint. A left pedestal member is rotatably connected to the left vertical lower portion of the left support member. Similarly the right pedestal member is rotatably connected to the right vertical lower portion of the right support member. Left edge tapering and right edge tapering, for some preferred embodiments, will be uniform from the left pedestal top and the right pedestal top respectively to the left support member top and the right support member top. These embodiments are particularly suited for displaying flat objects such as pictures, posters and other types of artwork or displays in sheet form. For certain preferred embodiments the pedestal angle between the pedestal top and the tapered outside edge for both the left support member and the right support member will be approximately 90°. The outside edge tapering and the pedestal top slope provide for a stable display of most display items. 
   When the left support member and right support member are rotated to the desired support angle and the positioning tab is lowered from an unlocked position to a locked position, a selected tab slot in the peripheral edge of the positioning tab rotates onto a tab rib thereby securing the support members at the desired support position with the desired support angle between the left support member and the right support member. The positioning tab is rotatably attached to the left support member or the right support member in a horizontal tab joint. When the positioning tab is in the unlocked position, the tab attached end lies within and conforms to the attachment insert. Similarly, when the left support member and right support member are aligned in a flat position, the tab free end fits within a receiving insert which is the tab insert opposite the attachment insert. The tab free end is not attached to either support member. This allows the free end to extend rearward behind a support member as the right support member and the left support member are rotated toward a display configuration. 
   A semi-circular positioning tab with a vertical tab end provides for the free rotation of the positioning tab from the unlocked position to the locked position with the tab free end freely rotating in the receiving insert and the selected tab slot readily rotating onto the tab rib until the positioning tab is in the locked position. The depth of the tab slots is preferably equal to the width of the tab rib, thereby providing additional friction to hold the positioning tab in the locked position. Also the positioning tab can be rectangular or in other geometric shapes. The shape of the tab used and the resultant shape of the receiving insert must provide for clearance of the tab top as it is rotated from the unlocked position to the locked position for the various support angles. The semi-circular design is a preferred embodiment because it provides for adequate clearance between the tab top and the tab insert top regardless of the support angle. 
   Preferred embodiments may also be provided with a horizontal left panel joint and a horizontal right panel joint which are aligned as they intersect the vertical central joint. For embodiments constructed of corrugated paperboard or other types of material collectively and commonly referred to along with corrugated paperboard as cardboard, these joints may be accomplished by scoring on the back side of the easel material. Depending upon the material used, other suitable hinge means are known in the industry. This allows the left support member top and the right support member top to be rotated downward to a compact configuration, thereby providing a more sturdy configuration for the display of heavier and more compact materials such as books. It should be noted, however, that in this compact configuration the positioning tab is not used. Other embodiments may also provide for the use of a positioning tab and tab insert at each of the vertical pedestal joints. This provides for additional stability, particularly for displaying heavier display items or very light display items. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a front perspective view of a preferred embodiment of the easel of the present invention in a display configuration with top support member panels in a full display position. 
       FIG. 2  is a front perspective view of a preferred embodiment of the easel of the present invention in a display configuration with top support member panels in a compact display position. 
       FIG. 3  is a front view of a preferred embodiment of the easel of the present invention in a flat configuration. 
       FIG. 4  is a front view perspective of a preferred embodiment of the positioning tab of the present invention in an unlocked position. 
       FIG. 5  is a front view perspective of a preferred embodiment of the positioning tab of the present invention in a locked position. 
   

   DETAILED DESCRIPTION 
   Referring first to  FIG. 1  the preferred embodiment of the easel  1  of the present invention shown is comprised of a left support member  3 , a right support member  5 , a left pedestal member  7 , a right pedestal member  9  and a positioning tab  11 . The left support member inside edge  13  is rotatably connected to the right support member inside edge  15  in a vertical central joint  17 . The left support member has a left outside edge  19  which has a left vertical lower portion  21  and a left tapered upper portion  23 . Similarly the right support member has a right outside edge  25  which has a right vertical lower portion  27  and a right tapered upper portion  29 . The left pedestal member inside edge  31  is rotatably connected to the left vertical lower portion in a vertical left pedestal joint  33 . Similarly the right pedestal member inside edge  35  is rotatably connected to the right vertical lower portion in a vertical right pedestal joint  37 . The left edge tapering  39  and the right edge tapering  41 , for some preferred embodiments, will be uniform from the left pedestal top  43  and the right pedestal top  44  respectively to the left support member top  45  and the right support member top  46  as shown in  FIG. 1 . Also for some preferred embodiments the left edge tapering and right edge tapering will be the same. These embodiments are particularly suited for displaying flat objects such as pictures, posters and other types of artwork or displays in sheet form. Also for certain preferred embodiments the pedestal angle  47  between the pedestal top and the tapered outside edge for both the left support member and the right support member will be approximately 90°. The outside edge tapering and the pedestal top slope  49  provide for a stable display of most common sized display boards, posters, charts and similar display items. 
   Referring now to  FIG. 4  and  FIG. 5  respectively, a preferred embodiment of the positioning tab  11  is shown. In  FIG. 4  the positioning tab is shown in the unlocked position  51 , while in  FIG. 5  the positioning tab is shown in the locked position  53 . Referring also to  FIG. 1 , when the left support member and right support member are rotated to the desired support angle  55  and the positioning tab is lowered from the unlocked position  51  to the locked position  53 , a selected tab slot  57  in the tab peripheral edge  54  is rotated onto the tab rib  58  thereby securing the support members at the desired support position  59  with the desired support angle  55 . For the embodiment shown the positioning tab is rotatably attached to the right support member in a horizontal tab joint  56 . When the positioning tab is in the unlocked position the tab attached end  60  lies within and conforms to the attachment insert  61  which, for the embodiment shown is the right tab insert  62 . 
   Similarly, when the left support member and right support member are aligned in a flat position  63  as shown in  FIG. 3 , the tab free end  65  fits within the receiving insert  66  which, for the embodiment shown, is the left tab insert  68  in the left support member adjacent to the vertical central joint  17 . The left tab insert and the right tab insert together form a central tab insert  70 . The tab free end is not attached to the left support member. This allows the free end to extend rearward  69  behind the left support member as the right support member and the left support member are rotated toward a display configuration  71  as shown in  FIG. 1 . For the preferred embodiment of the positioning tab shown in  FIG. 3 ,  FIG. 4 , and  FIG. 5 , a semi-circular positioning tab  11  with a vertical tab end  72  provides for the free rotation of the positioning tab from the unlocked position  51  to the locked position  53  with the tab free end freely rotating in the receiving insert and the selected tab slot readily rotating onto the tab rib  58  until the positioning tab is in the locked position  53 . The depth of the tab slots  73  is preferably equal to the tab rib width  75 , thereby providing additional friction to hold the positioning tab in the locked position. 
   The embodiment of the positioning tab shown in the figures, could readily be reversed with the left end being rotatably attached to the left support member and the tab rib being integral with the right tab insert, i.e. a mirror image of the positioning tab as shown in the figures. Also the positioning tab can be rectangular, oval, triangular or have other geometric shapes. Referring to  FIG. 4 , the shape of the positioning tab used and the resultant shape of the receiving insert must provide for clearance of the tab top  76  as it is rotated from the unlocked position to the locked position for the various support angles  55 . The semi-circular design shown in the figures is a preferred embodiment because it provides for adequate clearance between the tab top  76  and the tab insert top  78  regardless of the support angle. 
   Preferred embodiments may also be provided with a horizontal left panel joint  77  and a horizontal right panel joint  79  which are aligned as they intersect the vertical central joint  17  as shown in FIGS.  1 , 2  and  3 . For embodiments constructed of corrugated paperboard or other types of material collectively and commonly referred to along with corrugated paperboard as cardboard, these joints may be accomplished by scoring on the back side of the easel material. Depending upon the material used, suitable hinge material mechanisms are also known in the industry. This allows the left support member top panel  85  and the right support member top panel  87  to be rotated from a full display position  89  as shown in  FIGS. 1 and 3  downward to a compact configuration  91  as shown in  FIG. 2  thereby providing a more sturdy configuration for the display of heavier and more compact materials such as books. It should be noted, however, that in this compact configuration the positioning tab is not used. 
   Referring to  FIG. 1 ,  FIG. 2  and  FIG. 3 , it will be noted that the vertical central joint  17  and the vertical pedestal joints  33 ,  37  provide for the alinement of the left support member base  93 , the right support member base  95 , the left pedestal base  97 , and the right pedestal base  99  whether the easel is in a flat configuration or a display configuration, thereby providing a stable base for the easement on a level surface regardless of the support angle  55 . 
   Other embodiments, particularly in larger sizes, may also provide for the use of a positioning tab and tab insert at each of the vertical pedestal joints. This provides for additional stability, particularly for displaying heavier display items or very light display items. 
   Other objects, features and advantages of the present invention will become apparent from the preceding detailed description considered in connection with the accompanying drawings. It is to be understood, however, that the drawings and the foregoing description are designed as an illustration only and not as a definition of the limits of the invention. Therefore, the foregoing is intended to be merely illustrative of the invention and the invention is limited only by the following claims.