referring now to the drawings in which like numerals indicate like parts throughout the views , the preferred embodiment of the present invention will first be described structurally in its unfolded state and then be described as it is folded . turning first to fig1 - 5 , a foldable display unit 10 is shown in its unfolded state . the unit 10 comprises a base 12 , a front section 14 , a top section 16 and side sections 18 . the base 12 has a top surface 22 , a front surface 24 , a rear surface 26 , side surfaces 28 , and a bottom surface 30 . the base 12 has casters 20 extending downwardly from the bottom surface 30 . the top surface 22 of the base 12 has three steps : a front step 32 , a middle step 34 , and a rear step 36 . the steps are shaped to nestingly receive portions of the front section 14 and top section 16 when the unit 10 is folded . the front section 14 is hinged to the front surface 24 of the base 12 . in its unfolded state , the front section 14 rests adjacent to the front surface 24 of the base 12 . the width of the front step 32 of the base 12 is approximately the same as the width of the front section 14 so when the unit 10 is folded , the top of the front section 14 rests on top of the front step 32 , and the remaining dimensions of the front section are flush with and do not extend beyond the exterior dimensions of the base 12 . the top section 16 is joined to the base 12 along the rear surface 26 of the base 12 by means of conventional strap hinges 37 and two support hinges 38 , as shown fig5 and 6 . fig6 provides a detailed view of the support hinges 38 . each support hinge 38 includes a first leaf 40 , a second leaf 42 , a third leaf 44 and hinge pins 45 . the first leaf 40 of the support hinge 38 is secured to the rear of the top section 16 . the second leaf 42 of the support hinge 38 is joined to the first and third leaves 40 , 44 by means of the hinge pins 45 . the third leaf 44 has a vertical slot 46 therethrough . the first leaf 40 is secured to the top section 16 by bolts 49 and the third leaf 44 is also secured to the rear surface 26 of the base 12 by means of bolts 49 . an adjustment bolt 48 is located within the vertically oriented slot 46 . the position of the top section 16 relative to the base 12 may be adjusted by loosening the adjustment bolt 48 with a wrench ( not shown ) so as to allow the third leaf 44 to move along the slot 46 in a vertical direction . when the top section 16 is oriented substantially vertical , the third leaf 44 moves downward so that the second leaf 42 acts as a support beam and is oriented at an approximate 45 ° angle from the vertical . the position of the top section 16 relative to the base 12 is secured by tightening the adjustment bolt 48 that slides within the slot 46 . when the third leaf 44 has traveled downwardly as far as possible within the slot 46 , a stop plate 47 fixed to the rear surface of the base 12 , supports the third leaf and prevents any further downward movement of the third leaf . the top section 16 may be partitioned into shelves or compartments or the like as shown in fig1 to accommodate the display needs of the exhibitor . the top section 16 may also have lights mounted therein and / or translucent artwork mounted thereon so that the artwork is illuminated from within the top section . the top section 16 has an additional sign section 50 that is hinged by means of conventional butt hinges 51 to the top of the top section 16 in its unfolded position , as shown in fig4 . the sign section 50 is held vertically upright with respect to the top section 16 by a toggle latch mechanism 52 as shown in detail in fig7 . the toggle latch mechanism 52 includes a latch plate 53 secured to the top section 16 in an unfolded state , as shown in fig7 . a latching lever 54 is hinged to the latch plate 53 . a latching hook 55 is hinged to the latching lever 54 . a catch plate 57 is fastened to the sign section 50 . the catch plate 57 has a nib 59 . to fasten the sign section 50 in vertical position relative to the top section 16 , the latching lever 54 is pivoted toward the catch plate 57 so that the latching hook 55 is received into the nib 59 of the catch plate . the latching lever 54 is then moved adjacent to the latch plate 53 . a catch plate 57 is also mounted to the front surface of the base 12 so that the top section 16 is secured to the base by means of the toggle latch mechanism 52 when the unit 10 is folded , as shown in fig1 . the latch plate 53 has a loop 61 extending therefrom . the latching lever 54 has a slot 71 therein which receives the loop 61 when the latching lever is in its latched position . the hole in the loop 61 receives a padlock , chain or the like to secure the latching mechanism 52 when the unit 10 is folded . as shown in fig4 and 5 , the top section 16 also has side flaps 88 that protect the side surfaces of the top section when the unit 10 is folded . the side flaps 88 are substantially rectangular and flat and dimensioned to conform to the sides of the top section 16 when the unit 10 is folded . each side flap 88 is joined to the top edge of the top section 16 by means of sliding pin hinges 90 , shown in detail in fig9 . the sliding pin hinges 90 have fixed pins 91 extending from one side of the hinge . the other side of the hinge slidably receives the fixed pins 91 therein . when the unit 10 is unfolded , the side flaps 88 slide on the pins 91 of the sliding pin hinges 90 until the side flap disengages from the pin of the sliding pin hinge . the side flap 88 is then stored within the base 12 while the unit 10 is unfolded . returning to fig1 each side section 18 comprises a lower portion 56 and an upper portion 58 . both portions are substantially rectangular and flat and have substantially the same dimensions as the side surfaces 28 of the base 12 . the lower portion 56 is hinged to the upper portion 58 by means of continuous hinges 60 , as shown in fig2 . the lower portion 56 is flush against the upper portion 58 when the unit 10 is in its folded state . the side sections 18 are totally extended to their full height by rotating the upper portion 58 of the side section 18 approximately 180 ° upward from the lower portion 56 . the side sections 18 are secured in a vertical position by the toggle latch mechanism 52 attached to the lower and upper portions respectively . the operation of the toggle latch mechanism 52 in securing the position of the upper portion 58 relative to the lower portion 56 is similar to that described in detail above with regard to the sign section 50 . the latch plate 53 is secured to the lower portion 56 and the catch plate 57 is secured to the upper portion 58 , as shown in fig8 . two horizontally adjustable hinges 78 connect each lower portion 56 of the side section to the base 12 . the horizontally adjustable hinges allow for horizontal movement of the side sections 18 during folding and unfolding of the unit 10 . the horizontally adjustable hinge 78 , shown in detail in fig6 includes a frame leaf 80 secured , by means of screws 63 , to the upper end of the lower section 56 along the edge adjacent to the side surface 28 of the base 12 . a center leaf 82 is slidably attached to the rear surface 26 of the base 12 . the center leaf 82 has a pair of horizontally oriented slots 84 and threaded rods 86 within the slots . once the position of the side section 18 is determined , the threaded rods 86 are tightened to secure the side section 18 in place . because each side section 18 unfolds from the upper and lower portions 58 , 56 , the horizontally adjustable hinges 78 must be adjusted horizontally to eliminate any gap therebetween . the horizontally adjustable hinges 78 must also be capable of moving the side sections 18 outward to accommodate the thickness of the upper portion 58 folded against the lower portion 56 when the unit 10 is in its folded state . as stated above , the toggle latch mechanisms 52 are used to secure the upper portion 58 in a vertical position relative to the lower portion 56 . the toggle latch mechanisms 52 are also used to secure the side sections 18 to the top section 16 when the unit 10 is folded . the latch plate 53 of the toggle latch mechanism 52 is attached at two places to the exterior surface of the lower portion 56 of each side section 18 , as shown in fig5 . catch plates 57 are mounted to the side flaps 88 at similar locations to ensure alignment with the latch plates 53 attached to the lower portion 56 of each side section 18 when the unit 10 is folded . the catch plates 57 on the side flaps 88 receive the latching hooks 55 on the latch plates 53 mounted to the lower portion 56 to secure the side sections 18 to the top section 16 when the unit 10 is folded . the lower portion 56 has a hole 92 therethrough located so that when the lower and upper portions are folded , the hole aligns with a similar hole in the side surface 28 of the base 12 , as shown in detail in fig1 . the aligned holes 92 receive a turn fastener 94 to secure the side section 18 to the base 12 when the unit 10 is folded . when the unit 10 is unfolded , the fastener 94 rests within the hole 92 in the lower portion 56 . returning now to fig5 the rear surface 26 of the base 12 has a pair of cabinet doors 74 hinged to the base 12 that open outwardly . these doors 74 enable the user to store any display items in the base 12 , and other items such as the side flaps 88 when the unit 10 is unfolded . in addition , the cabinet doors 74 enable the user to have access to the display items after the unit 10 has been completely folded . to fold the unit 10 , the upper portion 58 of each of the side sections 18 is folded against the lower portion 56 , as shown in fig1 . this is accomplished by causing the latching lever 54 to disengage from the latching plate 53 , which is attached to the lower portion 56 of the side section 18 . the latching hook 55 clears the nib 59 of the catch plate 57 attached to the upper portion 58 of the side section 18 . once both of the toggle latch mechanisms 52 disengage , the upper portion 58 is folded over the lower portion 56 so that the display surfaces of the upper and lower portions contact one another . the horizontally adjustable hinges 78 that connect the lower portion 56 of one of the side sections 18 to the base 12 is unlocked by loosening the threaded rods 86 that slide within the horizontally oriented slot 84 within the center leaf 82 . once both horizontally adjustable hinges 78 are loosed on one side section 18 , the side section can move horizontally outward , away from the base 12 . this is done to accommodate the thickness of the folded upper portion 58 against the lower portion 56 . the folded side section 18 pivots 90 ° inward toward the side surface 28 of the base 12 about the horizontally adjustable hinges 78 . the process described above is repeated to fold the other side section 18 . the turn fastener 94 resting in the hole of the lower portion 56 is inserted into the aligned hole 92 in the base 12 . the turn fastener 94 is rotated so flint it is secure within the aligned hole 92 so as to ensure that each side section 18 remain secure against the base 12 when the unit 10 is shipped . turning now to fig1 , the front section 14 folds by pivoting upwardly 180 ° relative to the base 12 so that the top of the front section is nested on the front step 32 of the base . when the front section 14 is folded it supports a portion of the top section 16 in its folded position . the top section 16 is folded by first joining the side flaps 88 to the top section . the side flap 88 is slidingly received onto the sliding pin hinge 90 . then , the toggle latch mechanism 52 that secures the sign section 50 to the top of the top section is disengaged . this allows the sign section 50 to pivot 180 ° downward to rest flush against the front of the top section 16 . the top section 16 is then folded onto the base 12 by first loosening the adjustment bolt 48 within the vertically oriented slot 46 on the frame leaf 40 of one of the support hinges 38 . once the adjustment bolts 48 in both support hinges are loosened , the top section 16 rotates 90 ° in a forward direction relative to the base 12 to rest on the rear step 36 of the base and on the front section 14 . once the top section 16 is folded , it is secured to the front section 14 by means of the toggle latch mechanisms 52 . the latching hook 55 hinged to the latch plate 53 attached to the top of the top section 16 engages the nib 59 of the catch plate 57 mounted to the front of the front section 14 . the side sections 18 are secured to the base 12 by inserting the turn fastener 94 in the aligned holes 92 . the turn fastener 94 is rotated within the hole 92 to prevent the fastener from sliding out of the hole 92 . the completely folded unit 10 is shown in fig1 . as can be seen by comparing fig1 and 14 , the surfaces that are exposed when the unit 10 is completely folded are not exposed when the unit is completely unfolded . in addition , those surfaces that are exposed when the unit 10 is completely unfolded are not exposed when the unit is completely folded . this allows the display surfaces to remain free from scratching or marring that may occur during shipping of the folded unit . this also enables the exterior surfaces of the unit in its folded state to be made of resilient material capable of withstanding treatment typically given shipping containers . it should be understood that numerous modifications or alternations may be made to the device without departing from the spirit and scope of the invention as set forth in the appended claims . for example , it is contemplated that many alternative forms of joining the sections of the unit 10 together may be used instead of the hinges described above . examples of such joining mechanisms include slidable rod or channel assemblies , spring mechanisms , and certain linkage assemblies . such joining mechanisms are known by those skilled in the art . it should also be noted that relative terms such as &# 34 ; upper &# 34 ;, &# 34 ; lower &# 34 ;, &# 34 ; horizontal &# 34 ;, &# 34 ; vertical &# 34 ; and the like are used as a matter of convenience to define an internal frame of reference within the display unit , and are not intended to limit the orientation in which the unit may be used .
a foldable display unit having sections hingedly connected to a base wherein when the sections pivot inwardly toward the base , the sections and base fold into a self - contained portable shipping container . the unit includes a base , front section and top sections hingedly connected thereto . the top surface of the base is configured to nestingly receive the front and top sections when they are folded . the unit may also have side sections hingedly connected thereto . the side sections extend outwardly from the sides of the base in an unfolded state and pivot inwardly toward the sides of the base so that the sides are in face to face relation with the side surfaces of the base . latching mechanisms secure the hingedly connected sections to the base when the unit is folded .