Patent Publication Number: US-6701852-B2

Title: Collapsible multi-level pallet

Description:
FIELD OF THE INVENTION 
     The present invention relates to the field of pallets for transporting or storing goods. 
     BACKGROUND OF THE INVENTION 
     Pallets are often used for the purpose of transporting and storing goods in warehouses. Known pallets typically consist of a rectangular goods-supporting platform with feet which permit fork lift forks to pass underneath for lifting and transporting the pallet and its cargo. 
     Many warehouses employ rack or shelf systems to store pallets of goods at various heights within rack openings of a fixed height and width, with each rack opening being intended to store a single pallet of goods. To avoid wasting vertical space in a rack opening, it may be advantageous for the goods atop a pallet to be stacked in several layers. Such stacking is easily achieved when the goods are sturdy and of a uniform size and shape, because the top of each layer of goods forms a level platform for the next layer of goods. However, when the goods are oddly shaped, of non-uniform size, or fragile, such stacking may be impossible for reasons of instability or damage to goods. Disadvantageously, in such cases valuable rack opening space may be wasted. 
     What is needed is a pallet that overcomes the above-noted disadvantage, with the pallet further being collapsible to minimize storage space requirements when the pallet is not in use. 
     SUMMARY OF THE INVENTION 
     A collapsible multi-level pallet having a collapsed position and an erected position includes a lower goods-supporting platform and an upper goods-supporting platform. In the collapsed position, the upper goods-supporting platform lies flat over the lower platform. In the erected position, the upper platform is spaced from the lower platform. Goods may be loaded onto the lower and upper platforms of the erected pallet. A locking mechanism is used to lock the pallet in the erected position. An optional goods-supporting leaf is extendible from the raised upper platform into a position over the lower platform. The leaf may be supported in the extended position by deployable legs. The footprint of the pallet in its collapsed position is optionally no greater than the footprint of the lower platform. 
     In accordance with an aspect of the present invention there is provided a collapsible pallet comprising: a lower goods-supporting platform; an upper goods-supporting platform having a lowered position associated with a collapsed position of the pallet and a raised position associated with an erected position of the pallet, the upper platform being spaced from, and substantially parallel to, the lower platform when in the raised position so as to permit loading of goods onto the lower goods-supporting platform and the upper goods-supporting platform; and a first locking mechanism for locking the upper goods-supporting platform in the raised position. 
     In accordance with another aspect of the present invention there is provided a collapsible pallet comprising: lower goods-supporting platform means; upper goods-supporting platform means having a lowered position associated with a collapsed position of the pallet and a raised position associated with an erected position of the pallet, the upper platform means being spaced from, and substantially parallel to, the lower platform means when in the raised position so as to permit loading of goods onto the lower platform means and the upper platform means; and locking means for locking the upper goods-supporting platform means in the raised position. 
     In accordance with yet another aspect of the present invention, there is provided a collapsible pallet comprising: a lower goods-supporting platform; an upper goods-supporting platform having a lowered position associated with a collapsed position of the pallet and a raised position associated with an erected position of the pallet, the upper platform being spaced from, and substantially parallel to, the lower platform when in the raised position so as to permit loading of goods onto the lower goods-supporting platform and the upper goods-supporting platform; and a lock operatively coupled to at least one of the upper goods-supporting platform and the lower goods-supporting platform, the lock capable of selectively locking the upper goods-supporting platform in the raised position. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the figures which illustrate an example embodiment of this invention: 
     FIG. 1 is a perspective view of an embodiment of a multi-level pallet apparatus in a collapsed position; 
     FIG. 2 is a perspective view of the embodiment of FIG. 1 in a partially erected position; 
     FIG. 3 is a perspective view of the embodiment of FIG. 1 in an erected position; 
     FIG. 4 is a side view of the embodiment of FIG. 1 in a collapsed position; 
     FIG. 5 is a side view of the embodiment of FIG. 1 in a partially erected position; 
     FIG. 6 is a side view of the embodiment of FIG. 1 in another partially erected position; 
     FIG. 7 is a side view of the embodiment of FIG. 1 in an erected position; 
     FIG. 8 is a front view of the embodiment of FIG. 1 in an erected position illustrating the embodiment&#39;s deployable legs; 
     FIG. 9 is a top view of a locking mechanism of the embodiment of FIG. 1 in an unlocked position; 
     FIG. 10 is a side view of the locking mechanism illustrated in FIG. 8; and 
     FIG. 11 is a side view illustrating the stacking of multiple collapsed pallets. 
    
    
     DETAILED DESCRIPTION 
     Referring to FIGS. 1 to  8 , an exemplary collapsible multi-level pallet  12  with two levels is illustrated at various stages of being erected. FIGS. 1 and 4 illustrate the pallet  12  in a collapsed position, FIGS. 2,  5  and  6  illustrate the pallet  12  in various partially erected positions, and FIGS. 3,  7  and  8  illustrate the pallet  12  in an erected position. As will be appreciated, the collapsed position is for storage of the pallet  12  when it is not in use while the erected position is for use of the pallet  12  to store or transport goods. The pallet  12  has a front  15 , a rear  17 , a right side  19  and a left side  21 . It will be appreciated that the identification of the front, rear, and sides herein is for convenience of description only. In its collapsed position, the pallet  12  has a width W and a length L (FIG.  1 ). 
     The pallet  12  comprises two goods-supporting platforms, namely a lower platform  14  and an upper platform  16 , which are each capable of supporting goods that may be loaded onto the pallet  12 . In the present embodiment, each of these platforms  14  and  16  comprises a rectangular piece of steel mesh welded to a surrounding frame of angle-iron. In other embodiments, however, the platforms  14  and  16  may be made from other materials. 
     The frame of lower platform  14  comprises four angle iron members with “L-shaped” cross sections welded at their ends to form a rectangle. Each of the four members is oriented so that one half of the angle iron (i.e. the lower arm of the cross-sectional “L”) extends towards the center of the rectangle and is substantially horizontal while the other half of the angle iron (i.e. the upper arm of the cross-sectional “L”) extends upwardly from the horizontal portion at the perimeter of the frame. The lower platform  14  has a length L1 and a width W1 (FIG.  3 ). 
     The lower platform  14  includes a crossbar  48  (FIG. 1) welded lengthwise to the underside of its frame approximately equidistantly from the right and left sides  19  and  21 . A pair of cross bars  47   a  and  47   b  are also welded to the underside of the frame of lower platform  14  lengthwise along its right side  19  and left side  21 , respectively. The crossbars  48 ,  47   a  and  47   b  cumulatively increase the load-bearing capacity of lower platform  14  and serve as points of contact with fork lift forks that may be inserted transversely to the lower platform  14  for the purpose of lifting the pallet  12 . In the present embodiment, the crossbar  48  and cross members  47   a  and  47   b  comprise sections of angle iron oriented with the corner pointing downwardly. 
     The lower platform  14  is supported by four feet  40   a ,  40   b ,  40   c  and  40   d  (FIG. 1) which provide sufficient clearance between the lower platform  14  and the floor for fork lift forks to be inserted under the pallet  12  for lifting and transporting the pallet and any goods loaded thereupon. 
     Upper platform  16  has a similar construction to lower platform  14  with the exception of its dimensions and the arrangement of its frame. With respect to its dimensions, the width W2 of the upper platform  16  (FIG. 3) is slightly less than the width W1 of lower platform  14 , and the length L 2  of the upper platform  16  is approximately 60% of the length L1 of lower platform  14  (as shown in FIG.  3 ). 
     The frame of upper platform  16  comprises four angle iron members with “L-shaped” cross sections welded at their ends to form a rectangle. Three of the four members, namely right member  56   a , left member  56   b  and rear member  59  (FIG.  1 ), are arranged analogously to the members of the lower platform&#39;s frame. Front member  54  (FIGS. 5 to  7 ), on the other hand, is welded at its ends to the underside of right and left members  56   a  and  56   b  near their front ends with the corner of the angle iron pointing downwardly. As will become apparent, this arrangement of front member  54  permits a folding leaf  18  to be pivotably mounted along the front edge of the upper platform  16  so as to be extendible from its folded position (illustrated in FIGS. 1,  2 ,  4  and  5 ) to an unfolded or extended position (illustrated in FIGS.  3  and  7 ). A handle  46  suitable for grasping is centrally disposed on the rear angle iron member of upper platform  16  (FIGS.  2  and  3 ). 
     The upper arm of the cross-sectional “L” of the angle iron of sides  56   a  and  56   b  extends forwardly beyond the front member  54  to form brackets  60   a  and  60   b  respectively (FIG.  1 ). The brackets  60   a  and  60   b  each include a circular aperture for receiving a horizontal pin; the apertures are coaxial. 
     Four legs  20   a ,  20   b ,  22   a  and  22   b  (best seen in FIGS. 2,  3  and  5 - 7 ) interconnect the lower platform  14  and upper platform  16 . In the present embodiment, the legs comprise steel rods. One end of legs  20   a  and  20   b  is pivotally mounted to the underside of upper platform  16  at its right and left front corners by way of bracket pairs  30   a  and  30   b  respectively to permit pivoting of the legs around transverse axis A 1  (FIG.  2 ). The other end of each of legs  20   a  and  20   b  is pivotally connected at the edge of lower platform  14  by way of brackets  32   a  and  32   b  respectively so as to permit pivoting of the legs around transverse axis A 2 . Legs  22   a  and  22   b  are similarly mounted to the underside of upper platform  16  and to the upper surface of lower platform  14  at their right and left rear corners to permit pivoting of these legs around transverse axes A 3  and A 4  respectively. 
     As is visible in FIGS. 2 and 3, legs  20   a  and  20   b  of the present embodiment are mirror images of one another and are formed from a single steel rod bent back on itself to form a triangular upper portion which provides transverse stability to the pallet  12  when the upper platform  16  is raised. Legs  20   a ,  20   b  also have inwardly directed feet at their lower ends to provide interconnection points with the lower frame. Legs  22   a  and  22   b  are also mirror images of one another and comprise steel rods with feet at each end formed by bending the rods at right angles. The feet provide interconnection points with the upper platform  16  and lower platform  14 . The legs  20   a ,  20   b ,  22   a  and  22   b  have a uniform length between their connection point with the lower platform and their connection point with the upper platform and provide a sufficient vertical separation between the lower platform  14  and upper platform  16  when the pallet  12  is erected for goods to be loaded onto lower platform  14 . In the present embodiment, the length between connection points is also chosen so that, when the pallet  12  is collapsed, the horizontal displacement of the lowered upper platform  16  is not sufficient to cause the upper platform  16  to extend beyond the perimeter of lower platform  14  (thus, in the present embodiment, with the length L2 of the upper platform approximately 60% of the lower L1, the length of the legs  20   a ,  20   b ,  22   a  and  22   b  between their connection points is less than 40% of L1). This results in the footprint (i.e. length and width) of collapsed pallet  12  being no greater than the footprint of the lower platform  14 . Space requirements for storing the collapsed pallet  12  may therefore be reduced. Advantageously, it may be possible to store collapsed pallets  12  within the same rack openings that may be used to store erected pallets  12  that are loaded with goods. 
     The pallet  12  further comprises a goods-supporting leaf  18  (FIG.  3 ). Leaf  18  comprises a rectangular frame of angle-iron welded to a steel mesh. The orientation of the angle iron members of the frame of leaf  18  when the pallet  12  is in its erected position (FIG. 3) is the same as orientation of the angle iron members of lower platform  14 . The leaf  18  has a length L3 and a width W3 (FIG.  3 ). The combination of the length L3 of the leaf  18  and the length L2 of the upper platform  16  is substantially equal to the length L1 of the lower platform  14  so that, when the pallet  12  is erected, the cumulative length of the upper platform  16  and adjacent extended leaf  18  is substantially the same as the length L1 of the lower platform  14 . The width W3 of the leaf  18  is slightly smaller than the width W2 of the upper platform  16  to permit the leaf  18  to be partially nested within the upper platform  16  when the leaf  18  is in its folded position, as best seen in FIG.  4 . 
     Two pins  50   a  and  50   b  (FIG. 1) are welded to the rear edge  44  of leaf  18  (with “rear” referring to the position of the edge  44  when the leaf  18  is in its position shown in FIG.  3 ). The pins  50   a  and  50   b  are horizontal and coaxial as shown in FIG.  1  and are rotatably received by the apertures in brackets  60   a  and  60   b  respectively. The pins  50   a  and  50   b  define an axis of rotation about which the leaf  18  may be pivoted to move the leaf  18  from its stored position (FIGS. 1,  2 ,  4 , and  5 ) to its extended position (FIGS.  3  and  7 ). 
     The leaf  18  of the present embodiment includes a pair of deployable legs  24   a  and  24   b  (FIGS. 1,  2 , and  8 ). The legs  24   a  and  24   b  are mirror images of one another and are formed from a single steel rod bent back on itself to form a triangular upper portion which provides lengthwise stability to the pallet  12  when it is erected (FIG.  3 ). Each leg  24   a  and  24   b  has a foot  25   a  and  25   b  formed by bending the ends of the legs  24   a  and  24   b  at a right angle, with the feet  25   a  and  25   b  extending upwardly when the pallet  12  is in a collapsed position (FIG.  2 ). A pair of abutments  28   a  and  28   b  (FIGS. 1 and 2) welded to the frontward bend of the legs  24   a  and  24   b  respectively serve as limiters to prevent excessive outward pivoting of the legs, as will be described. The legs  24   a  and  24   b  are pivotally connected to the underside of leaf  18  at its right and left edges by way of bracket pairs  26   a  and  26   b , with “underside” referring to the surface of the leaf  18  which faces downwardly when the pallet  12  is in its erected position. The brackets permit pivoting of these legs through a 90 degree angle (as shown in FIG. 8) around longitudinal axes that are substantially parallel to the right and left side of leaf  18 , respectively. Notably the pivot axes of legs  24   a ,  24   b  are at a right angle to the pivot axes of each of legs  20   a ,  20   b ,  20   c  and  20   d.    
     The lower platform  14  includes a pair of locking mechanisms  36   a  and  36   b  (cumulatively comprising first locking mechanism  36  of FIG. 3) situated in its right and left front corners respectively (FIGS. 1-3 and  8 ) which are used to lock the feet  25   a  and  25   b  into position when the legs  24   a  and  24   b  are deployed, as shown in FIG. 8 for example. Enlarged top and side views of mechanism  36   a  are provided in FIGS. 9 and 10 respectively. The mechanism  36   a  comprises annular member  32   a  capable of receiving foot  25   a  when the leg  24   a  is deployed. The mechanism further comprises a bracket  42   a  pivotably supporting a retaining bar  38   a  capable of pivoting between an open position (illustrated in FIGS. 9 and 10) and a closed position (illustrated in FIGS.  3  and  7 ). When the retaining bar is in the open position, the foot  25   a  may be freely inserted into or removed from the annular member  32   a  through rotation of the leg  24   a  (as shown in FIG.  8 ). When the retaining bar  38   a  is in the closed position, removal of the inserted foot is prevented. The other locking mechanism  36   b  is a mirror image of mechanism  36   a.    
     A second locking mechanism comprising a chain  80  (FIG. 1) selectively tethers leaf  18  of the collapsed pallet  12  to lower platform  14 . The two ends of chain  80  are unremovably affixed to the steel mesh of the leaf  18  so as to leave slack in the chain  80 . The middle of the slackened chain  80  may be pulled over the legs  24   a  and  24   b  of leaf  18  (forming the chain  80  into a “V” shape) and secured to the lower platform  14  with a clip (not shown) which forms part of the chain. The clip may be a conventional key ring attached to the middle of the chain  80  for example. When secured, the chain  80  maintains the pallet  12  in its collapsed position even when the pallet  12  it is set on its edge or inverted. The secured chain  80  overlays legs  24   a  and  24   b  of leaf  18  to maintain them in their undeployed positions. 
     In operation, a person desirous of using the multi-level pallet  12  sets the collapsed pallet onto a hard surface as shown in FIG.  1 . The middle of chain  80  is detached from the lower platform  14  to release the upper platform  16  and leaf  18 . The middle of the chain  80  may then be pulled towards the front of the pallet  12  to take up any slack and attached to the mesh to the leaf  18  to prevent dangling of the chain  80  when the pallet  12  is erected. Advantageously, because the chain is not detached from the pallet  12 , it does not have a tendency to become lost. 
     Standing at the rear  17  (FIG. 1) of the pallet  12 , the user grasps the handle  46  at the rear of upper platform  16  and pulls upwardly and rearwardly. This causes the upper platform  16  and folded leaf  18  to be translated upwardly and rearwardly away from lower platform  14  (FIG. 5) to the partially erected position shown in FIG.  2 . During translation, the legs  20   a ,  20   b ,  22   a  and  22   b  pivot from their horizontal collapsed positions (FIG. 4) about axes A 2  and A 4  until a lower rearward portion of legs  22   a  and  22   b  abuts the upstanding portion of the rear angle iron member of lower platform  14  at abutment point  60  (FIG.  2 ). At abutment point  60 , the legs  22   a  and  22   b  (as well as legs  20   a  and  20   b ) are inclined slightly beyond the vertical in the rearward direction. This permits the pallet  12  to rest in the partially erected state shown in FIG. 2 without being held by the user. 
     The user subsequently pivots the leaf  18  (as shown in FIG. 6) through an angle of 180 degrees until it achieves an extended position in which it is coplanar with raised upper platform  16 . With the assistance of gravity, the legs  24   a  and  24   b  of leaf  18  pivot downwardly through a 90 degree angle about bracket pairs  26   a  and  26   b  to a substantially vertical deployed position as shown in FIG.  8 . Excessive outward pivoting of the legs  24   a  and  24   b  is prevented by contact between abutments  28   a  and  28   b  and the underside of the frame of unfolded leaf  18  (FIG.  8 ). With the retaining bars  38   a  and  38   b  in their open positions, the feet  25   a  and  25   b  of legs  24   a  and  24   b  are inserted into annular members  32   a  and  32   b  of first locking mechanism  36 . The retaining bars  38   a  and  38   b  are then closed (as shown in FIG. 7) to prevent removal of the feet  25   a  and  25   b . Because the pivot axes of feet  24   a ,  24   b  are not parallel with those of legs  20   a  to  20   d , with the feet anchored in the annular members  32   a  and  32   b , the pallet  12  is locked in the erected position (FIG.  3 ). Advantageously, the pallet  12  may be erected by a single user. 
     Once erected, both levels of the pallet  12  may be loaded with goods. In the present embodiment, the goods are preferably loaded from the front  15  or back  17  of the pallet  12  to facilitate positioning of the goods on the upper surface  16 , leaf  18  and lower platform  14  through sliding. Lengthwise sliding is facilitated by the parallel alignment of the wires comprising the upper surface of the mesh of upper platform  16 , leaf  18  and lower platform  14  in a lengthwise direction. Loading of goods from the sides of pallet  12  is also possible but may be more difficult due to increased sliding resistance in a transverse direction presented by the broad side of the lengthwise wires. Of course, in an alternative embodiment the mesh of the upper platform  16 , leaf  18  and lower platform  14  may be rotated by 90 degrees to facilitate transverse loading instead of lengthwise loading. 
     Advantageously, at least two layers of goods (one per pallet level) may be loaded onto the erected pallet  12 , even when goods cannot be stacked due to being oddly shaped, of non-uniform size, or fragile. 
     Disassembly of the unloaded pallet  12  is achieved by performing the above described assembly steps in reverse order. 
     It will be appreciated that all parts are integral to the pallet. This is advantageous in that it reduces the risk of lost components. 
     For convenient storage, multiple collapsed pallets  12   a  and  12   b  may be stacked as shown in FIG.  11 . When stacked, the feet  40   a - 40   d  of an upper pallet  12   a  rest on the angle iron members of lower platform  14  of the underlying pallet  12   b . Horizontal displacement of the upper pallet  12   a  is limited by the upstanding perimeter of pallet  12   b &#39;s lower platform frame. Moreover, the feet  40   a - 40   d  of the upper pallet  12   a  define a volume A beneath that pallet&#39;s lower platform  14  into which at the upper platform  16 , leaf  18  and deployable legs  24   a  and  24   b  of the lower pallet  12   b  are received. Advantageously, the height of stacked pallets is thereby diminished, reducing storage space requirements. 
     As will be appreciated by those skilled in the art, modifications to the above-described embodiment can be made without departing from the essence of the invention. For example, the lower platform  14 , upper platform  16 , and leaf  18  need not be comprised of steel mesh welded into an angle iron frame. Any rigid flat goods-supporting surface may be used. 
     Different locking mechanisms than those described herein may be used in alternative embodiments. For example, instead of the first locking mechanism  36  (FIG.  3 ), the free ends of legs  24   a  and  24   b  may each comprise a nub which may be passed through a wide end of a narrowing, horizontally oriented slot in the right and left frame member (respectively) of lower platform  14 . When the free ends of the legs  24   a  and  24   b  are slid along the slot, the narrowed width of the slot prevents removal of the nub and the leg end is thereby secured, in an analogous manner to the chain-lock mechanism commonly used to chain residential doors for example. 
     Some embodiments may not include a leaf  18 . In such leafless embodiments, the upper platform  16  may have a footprint that is less than the footprint of the lower platform  14 , resulting in a portion of the pallet  12  being bi-level and the remainder of the pallet  12  being uni-level. This type of arrangement may be desired in cases where tall goods are to be stored alongside short goods, as the tall goods may be loaded onto the uni-level portion of the pallet  12  and the short goods may be loaded onto either level of the bi-level portion. Alternatively, the upper platform  16  may have an extent that is the same as lower platform  14 . In this case, the erected pallet will be entirely bi-level, however, the extent of the collapsed pallet will exceed the extent of the lower platform  14 . In either case, the absence of a leaf  18  will necessitate a change in the mechanism used to lock the pallet  12  in the erected position, as the described anchor point for the deployable legs  24   a  and  24   b  (the underside of the leaf  18 ) will not exist. In one alternative, the deployable legs  24   a  and  24   b  may be attached to the underside of the upper platform  16  rather than under the leaf  18  using the brackets  26   a  and  26   b , in which case the locking mechanisms  36   a  and  36   b  may be relocated underneath brackets  26   a  and  26   b  (respectively) to facilitate locking. In another alternative, in place of deployable legs  24   a  and  24   b  and mechanism  36 , a simple bracket and pivotable retaining bar analogous to bracket  42   a  and retaining bar  38   a  of FIGS. 9 and 10 may be situated at the right and left sides  19  and  21  (FIG. 1) of lower platform  14 , with the axis of rotation of the retaining bars being longitudinal. When in the closed position, the retaining bars may abut the front side of legs  20   a  and  20   b  of the erected pallet  12  and thus lock the pallet  12  in the erected position. When in the open position, the front side of legs  20   a  and  20   b  is unobstructed and the pallet  12  may be collapsed. 
     In another alternative, the leaf  18  may not be pivotably connected to the upper platform  16 . Rather, the leaf  18  may be extendable from upper platform  16  in another manner. For example, the leaf  18  may be telescopingly connected to upper platform  16  so as to be extendible from the raised upper platform  16  through the application of horizontal pulling force onto the leaf  18 . Such alternative leaf  18  arrangements may or may not include deployable legs. For example, a telescoping leaf  18  may employ a mechanism similar to an oven rack system to support the leaf  18  when extended. That is, the upper platform  14  may include, for example, a horizontal slot with upturned ends in its right and left frame members which each receive a pin protruding laterally from the leaf  18 , and the upper platform  14  may have suitable surrounding structure, so that when the front of the leaf  18  is raised, the laterally protruding pins are lowered from the rear slot ends, and the leaf  18  may be pulled forwardly in the inclined position until, by dropping the front of the leaf  18  to make the leaf  18  once again horizontal, the pins slide into the upturned front slot ends, and the leaf  18  is thus locked in the extended position. 
     Also, while the present embodiment is capable of standing in a partially erected state as shown in FIG. 6 due to the abutment of the legs  22   a  and  22   b  against the upstanding rear edge of lower platform  14  at abutment points  60  (FIG.  2 ), it is not necessary to include this feature in alternative embodiments. Of course, it may be difficult for a single individual to assemble or disassemble such embodiments. 
     As well, it is not necessary for all parts of the pallet  12  to be permanently joined. However, the use of separate parts may be disadvantageous in that such parts may become separated from the pallet and may become lost. 
     Finally, though the exemplary multi-level pallet  12  is illustrated herein as a bi-level pallet, it will be appreciated that the pallet  12  may be implemented with more than two levels. For example, a third “middle” platform may be affixed at the midpoint of the legs  20   a ,  20   b ,  22   a , and  22   b  by way of pivotal connections so as to permit the platform to be sandwiched between the upper and lower platforms  16  and  14  when the pallet  12  is collapsed, and so that the middle platform is horizontally supported at the midpoint of legs  20   a ,  20   b ,  22   a  and  22   b  when the pallet  12  is erected. Alternatively, in a leafless embodiment, an additional third level may be added above the upper platform  16 . More specifically, the mechanism which attaches the lower platform  14  to the upper platform  16  may be reproduced at upper platform  16  to collapsibly support a third, uppermost platform. In such an embodiment, an alternative first locking mechanism to mechanism  36 , as described above with respect to the leafless embodiment, may be employed. 
     Other modifications will be apparent to those skilled in the art and, therefore, the invention is defined in the claims.