Patent Publication Number: US-2017349324-A1

Title: Collapsible crate

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application claims the benefit of U.S. Provisional Patent Application No. 62/344,748, filed Jun. 2, 2016, which is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND 
     Various different styles of crates are available for industrial packaging. In certain applications, these crates must be strong enough to support large payloads. For example, industrial packaging crates are used for the protection, shipment and/or storage of all-terrain vehicles (ATVs), snowmobiles, motorcycles, boat motors, and other heavy payloads. Often, these crates are collapsible so that they can be disassembled and returned once empty. For ATVs and other payloads, these crates typically use an all-steel construction, which is expensive. To reduce cost, others have used crates made at least partially from cardboard, but these crates are not strong enough for stacking. Other crates have used wood, but these are often configured to be disposed of after one use, and are not collapsible or returnable. Other wood crates are collapsible and may be returnable/reusable, but these require additional hardware to assemble and collapse, and are typically not designed to be durable enough for more than a few uses. 
     BRIEF SUMMARY 
     According to one embodiment of the invention, a collapsible crate includes a structural base having at least one corner, and a collapsible corner post assembly coupled to the base. The corner post assembly includes a post mount coupled to the corner and an elongated post coupled to the post mount. The elongated post is moveable relative to the post mount between an upright position in which the elongated post extends substantially vertically and a collapsed position in which the elongated post lies substantially horizontally. 
     According to another embodiment of the invention, a collapsible corner post assembly for a crate includes a post mount and an elongated post coupled to the post mount. The elongated post is moveable relative to the post mount between an upright position in which the elongated post extends upwardly from the post mount and a collapsed position in which the elongated post extends laterally from the post mount. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1  is a perspective view of a crate according to a first embodiment of the invention, with the crate shown in an assembled configuration; 
         FIG. 2  is a side view of the crate of  FIG. 1 ; 
         FIG. 3  is an end view of the crate of  FIG. 1 ; 
         FIG. 4  is a perspective view of two stacked assembled crates of  FIG. 1 ; 
         FIG. 5  is a side view of the stacked assembled crates of  FIG. 4 ; 
         FIG. 6  is an end view of the stacked assembled crates of  FIG. 4 ; 
         FIG. 7  is a perspective view of two stacked collapsed crates of  FIG. 1 ; 
         FIG. 8  is a side view of the stacked collapsed crates of  FIG. 7 ; 
         FIG. 9  is an end view of the stacked collapsed crates of  FIG. 7 ; 
         FIG. 10  is an exploded view of a corner portion of the crate of  FIG. 1 ; 
         FIG. 11  is a perspective view of a corner post assembly of the crate of  FIG. 1 , where the corner post assembly is in an upright and extended position; 
         FIG. 12  is a perspective view of the corner post assembly of  FIG. 11 , where the corner post assembly is in an upright and retracted position; 
         FIG. 13  is a perspective view of the corner post assembly of  FIG. 11 , where the corner post assembly is in a collapsed position; 
         FIGS. 14-16  are views showing the movement of the corner post assembly from the upright position to the collapsed position; 
         FIG. 17  is a perspective view of a crate according to a second embodiment of the invention, with the crate shown in an assembled configuration; 
         FIG. 18  is a perspective view of two stacked assembled crates of  FIG. 17 ; 
         FIG. 19  is a perspective view of two stacked collapsed crates of  FIG. 17 ; 
         FIG. 20  is an exploded view of a corner portion of the crate of  FIG. 17 ; 
         FIG. 21  is a close-up perspective view of the top of one of the corner post assembly of the crate of  FIG. 17 ; 
         FIG. 22  is a close-up view of an interface between the stacked crates shown in  FIG. 18 ; 
         FIGS. 23-24  are views showing the movement of the corner post assembly from the upright position to the collapsed position; 
         FIG. 25  is a side view of a portion of a corner post assembly for a crate according to a third embodiment of the invention, with the corner post assembly shown in an assembled position; 
         FIG. 26  is a side view of a portion of the corner post assembly from  FIG. 25 , with the corner post assembly shown in a collapsed position; and 
         FIG. 27  is a perspective view of a portion of the corner post assembly from  FIG. 25 , with the corner post assembly shown in a collapsed position. 
     
    
    
     DETAILED DESCRIPTION 
     The invention relates to a crate for industrial packaging. In one of its aspects, the invention relates to an improved crate that is collapsible, stackable, and, optionally, returnable. The crate can be reusable, and can be easily and conveniently assembled or disassembled as needed. Areas in which the invention has potential application include the protection, shipment and/or storage of goods, including a wide variety of products. The crate may be primarily used for industrial, mid-stream payload transport, and can be used in any number of transport modalities. One particular application in which the crate is contemplated for use is the protection, shipment and/or storage of all-terrain vehicles (ATVs). Other particular applications in which the crate is contemplated for use is the protection, shipment and/or storage of snowmobiles, motorcycles, boat motors, and other heavy payloads 
       FIGS. 1-3  show a collapsible, stackable, and returnable crate  10  according to one embodiment of the invention. There are three primary component groups of the crate  10 , including a structural base  12 , collapsible corner post assemblies  14 , and various mechanical fasteners, described in more detail below. For purposes of description related to the figures, the terms “upper,” “lower,” “vertical,” “horizontal,” and derivatives thereof shall relate to an orientation of the crate  10  as shown in  FIG. 1 , with a lower side of the crate facing and resting on a surface (not shown). However, it is to be understood that the invention may assume various alternative orientations, except where expressly specified to the contrary. 
     The structural base  12  defines a support surface for a payload. The structural base  12  can be preferably fabricated from wood, while the corner post assemblies  14  can be preferably fabricated from metal, such as steel. This combination of materials offers a reduced-cost, collapsible crate that is robust enough to support large payloads such as ATVs, and can further be stacked when assembled with at least one other crate  10  as shown in  FIGS. 4-6  or stacked when collapsed with at least one other crate  10  as shown in  FIGS. 7-9 . 
     The structural base  12  may be customized based on the payload. The structural base  12  of the illustrated embodiment is customized for an ATV, and includes a plurality of boards or slats that are mechanically fastened to each other to create the structural base  12 . The slats include a plurality of bottom deckboards  18  and a plurality of top deckboards  20  that are mechanically fastened to a plurality of stringer boards  22  running transversely to and between the deckboards  18 ,  20 . Blocks  24  can also be provided between and mechanically fastened to the end deckboards  18 ,  20 , and can lie between adjacent stringer boards  22 . Mechanical fasteners such as nails, screws, pins, bolts, rivets, ties, or the like can be used for the mechanical attachments of the base  12 . Furthermore, other joining methods of assembling the base  12  can also be used. 
     Other embodiments of the structural base  12  are possible, including different configurations of the slats than that shown herein. While a customized base  12  is shown herein, the base on which the corners posts  14  are mounted can be any type of base. For example, in one embodiment, the structural base  12  can be a pallet. Furthermore, the corner post assemblies  14  are adapted to be transferred between different types of bases, as described in further detail below. Also, while it is preferred that the structural base  12  be manufactured from a low-cost material such as wood, in other embodiments of the crate  10 , the structural base  12  can be manufactured using a variety of materials including wood, plastic, composite, metal, fiberglass, wood-plastic composite, or some combination of these materials. In some applications of the crate  10 , it is preferred that the structural base  12  be constructed of a material that is lower cost than the material used for the corner post assemblies  14 . 
       FIG. 10  is an exploded view of a corner portion of the crate  10  of  FIG. 1 , and shows one of the corner post assemblies  14  exploded from a corner of the structural base  12 . The collapsible corner post assemblies  14  are upright supports configured to provide lateral protection to the payload supported by the base  12 , and are adapted to allow multiple crates to be stacked when assembled or when collapsed shown in  FIGS. 4-9 . The corner post assemblies  14  can include a telescoping post  26 , a post mount  28  configured to couple the telescoping post  26  to the structural base  12 , diagonal attachment plates  30  mountable to the structural base  12 , and diagonal braces  32  extending between the telescoping posts  26  and the attachment plates  30 . While in the illustrated embodiment, the corner post assembly  14  is shown as having a telescoping post  26 , in other embodiments of the crate  10 , the post  26  can be a single post having a fixed length. 
     The various components of the corner post assembly  14  can be attached using mechanical fasteners; alternatively, some of the various components can be welded, or otherwise attached. While the corner post assemblies  14  can be preferably fabricated from metal, and more particularly from steel, in other embodiments, the corner post assemblies  14  can be manufactured using a variety of materials including metal, plastic, composite, wood, fiberglass, wood-plastic composite, or some combination of these materials. In some applications of the crate  10 , it is preferred that the corner post assemblies  14  be constructed of a material that is more robust than the material used for the structural base  12 , so that the corner post assemblies  14  can withstand the repeating stacking and collapsing required of the collapsible, stackable, and returnable crate  10 . 
     The telescoping post  26  can include multiple segments that can be expanded or retracted as needed to change the length of the telescoping post  26 , and as illustrated herein includes a corner post main upright  34  and a corner post insert  36  that fits into the main upright  34 . Additional telescoping segments may be provided. 
     The main upright  34  includes an elongated tubular body  38  defining an at least partially hollow interior and having an open upper end  40  in which the post insert  36  can be at least partially received and an open lower end  42  which couples with the post mount  28 . Tabs  44  extend from the lower end  42  of the tubular body  38  and include slots  46  which are elongated generally in the lengthwise direction of the main upright  34 . The slotted tabs  44  can comprise a pair of plates or flat bodies provided on opposing sides of the tubular body  38 . A series of holes  48  are formed along the same opposing sides of the tubular body  38 , and are spaced along the length of the tubular body  38 . Each hole  48  on one side of the tubular body  38  is aligned with a hole  48  on the opposing side, though only one holes  48  on the opposing side is visible in  FIG. 10 . Brace tabs  50  extend from the tubular body  38  and each has a hole  52  formed near a free end of the tab  50  for coupling with the diagonal braces  32  as described in more detail below. In the illustrated embodiment, the brace tabs  50  extend laterally from adjacent sides of the tubular body  38 . Alternative configurations of attaching the diagonal braces  32  to the main upright  34  are possible, as long as the braces  32  are able to collapse, as described in more detail below. 
     The post insert  36  includes an elongated tubular body  54  defining an at least partially hollow interior and having an upper end  56  and a lower end  58  which is received with the main upright  34 . A series of holes  60  are formed along opposing sides of the tubular body  54 , though only the holes  60  on one of the opposing sides are visible in  FIG. 10 , and are spaced lengthwise along the tubular body  54 . Each hole  60  on one side of the tubular body  54  is aligned with a hole  60  on the opposing side. In the illustrated embodiment, two holes  60  are provided, though the number can vary in other embodiments of the corner post assembly  14 . The spacing between the holes  60  can be in line with the spacing between the holes  48  in the main upright  34 . 
     The post insert  36  can be slidingly received within the main upright  34  and adjusted to a desired overall height of the corner post assembly  14 . To fix the corner post assembly  14  at a desired height, one of the holes  60  in the post insert  36  is aligned with one of the holes  48  in the main upright  34 , and a mechanical fastener is then inserted through the aligned holes  48 ,  60  to secure the main upright  34  and post insert  36  in place at the desired height. The mechanical fastener illustrated herein comprises a bolt  62  and a nut  64  which can be threaded onto the bolt  62 ; optionally, a washer  66  can also be provided. Other mechanical fasteners are possible, as long as the mechanical fastener can temporarily join the main upright  34  and post insert  36  to allow the height of the corner post assembly  14  to be adjusted as needed. Any fastener can be used, as long as there is enough sheer strength in the fastener to carry the load on the corner post assembly  14 . 
     The upper end  56  includes a top plate  68  and a locator pin  70 . The plate  68  can extend outwardly from the tubular body  54  and the locator pin  70  can extend upwardly from the plate  68 . The locator pins  70  are adapted to nest into the post mount  28  of another corner post assembly  14  for securely stacking the crates  10  (see, for example,  FIGS. 4-6 ). As illustrated, the locator pins  70  have a generally conical shape which can guide an upper crate  10  in the stack into proper alignment with a lower crate  10 . Alternative configurations of the locator pin  70  are possible, as long as the crates  10  can be securely stacked, with the locator pins  70  of the lower crate  10  in the stack securely nested within a portion of the corner post assemblies  14  on the crate  10  above. 
     The post mount  28  includes a vertical mounting plate  72  and a horizontal mounting plate  74  coupled with a post receiver  76  configured to receive the telescoping post  26 . The mounting plates  72 ,  74  are configured to mount to the structural base  12 , thereby mounting the telescoping post  26  to the structural base  12 . Specifically, the vertical mounting plate  72  is coupled to the stringer board  22  and the horizontal mounting plate  74  is mounted to the top deckboard  20 , though in other configurations of the base, the plates  72 ,  74  may mount to other portions of the base. The mounting plates  72 ,  74  can be fabricated from one flat plate that is bent to define the corner between two plates  72 ,  74 , and then welded or otherwise attached to the post receiver  76 . Alternatively, the plates  72 ,  74  can be fabricated separate flat plates that are welded or otherwise attached to form the corner. 
     Each plate  72 ,  74  includes at least one hole  78  configured to receive a mechanical fastener, illustrated herein as a carriage bolt  80 , used to secure the plates to the structural base  12 . Other mechanical fasteners are possible, as long as the mechanical fastener can temporarily join the mounting plates  72 ,  74  to the base  12  to allow the post mount  28  to be removed from the structural base  12  as needed. As illustrated, the vertical mounting plate  72  includes two holes  78  that are spaced and vertically offset. Offsetting the holes  78  vertically distributes the forces from the payload over a greater area within the stringer board  22 . In general, the holes  78  can be aligned vertically, aligned horizontally, and/or offset depending on the application and constraints. Also, in the illustrated embodiment, two holes  78  are provided, though the number can vary in other embodiments of the corner post assembly  14 . 
     The post mount  28  can be configured as a universal mount, such that the corner post assemblies  14  can be attached to any base, not just the structural base  12  illustrated herein. The mounting plates  72 ,  74  can be sized to accommodate attaching the post mount  28  to a base  12  having boards or slats in a range of sizes. For example, the vertical mounting plate  72  and horizontal mounting plate  74  can be sized to accommodate attaching the post mount  28  to a 2×3 or larger stringer board  22  and a 1× or larger deckboard  20 , respectively. In one specific example, the plates  72 ,  74  can be sized to accommodate attaching the post mount  28  to a 2×3 stringer board  22  and a 2× deckboard  20 . In another specific example, the plates  72 ,  74  can be sized to accommodate attaching the post mount  28  to a 2×4 stringer board  22  and a 1× deckboard  20 . The plates  72 ,  74  could be sized to work with smaller or larger stringer board/deckboard combinations as well. 
     The post receiver  76  includes an elongated tubular body  82  defining an at least partially hollow interior and having an open upper end  84  which engages with the main upright  34  and an open lower end  85  ( FIG. 11 ). A locator device, shown herein as locator tabs  86 , can extend from the upper end  84  of the tubular body  82 , and can extend generally in the lengthwise direction of the post receiver  76 . The locator tabs  86  illustrated comprise a pair of plates or flat bodies provided on opposing sides of the tubular body  82  and project from an inner surface of the tubular body  82 . The locator tabs  86  can be welded, bolted, or otherwise formed with the post receiver  76 . The locator device can take other forms besides the tabs  86 , including, but not limited to, round or square tubing or bar stock. 
     At least one pair of holes  88  is formed along the same opposing sides of the tubular body  82  as the locator tabs  86 , though only the hole  88  on one of the opposing sides is visible in  FIG. 10 . In the illustrated embodiment, two spaced holes  88  are provided and are spaced lengthwise along the tubular body  82 , though the number of holes  88  can vary in other embodiments of the corner post assembly  14 . Here, the upper hole  88  is primarily used for the connection between the telescoping post  26  and post mount  28 , while the lower hole  88  is used for heavy duty loads, as described in more detail below. 
     In the illustrated embodiment, the bodies  38 ,  82  of the main upright  34  and post receiver  76  can be square 2×2 tube stock and the body of the post insert  36  can be square 1.5×1.5 tube stock that can nest within the outer tube stock forming the main upright  34 . Alternatively, tube stock can be substituted for a material that preserves the stacking and nesting functions of the corner post assembly  14 . Also, while the tubular bodies are shown as having a square cross-section, other cross-sectional shapes are possible. 
     The main upright  34  can be slidingly received on the post receiver  76  to couple the telescoping body  26  with the post mount  28  and also selectively allow the telescoping body  26  to collapse, as described in further detail below. To fix the main upright  34  on the post receiver  76 , a mechanical fastener such as a bolt  90  and a nut  92  which can be threaded onto the bolt  90  can be used; optionally, a washer  94  can also be provided. In the present embodiment, the bolt  90  is received by the slots  46  in the depending tabs  44  of the main upright  34  and the upper holes  88  in the post receiver  76 . The bolt  90  and slotted tabs  44  form a pin-in-slot joint between the telescoping post  26  and the post mount  28 , which has two degrees of freedom such that the bolt  90  can slide within the slot  46 , and the tab  44 , and therefore the post  26 , can rotate about the bolt  90 . Other joints permitting translational and rotating movement between the post  26  and post mount  28  can also be used. Also, while not shown, for heavy duty loads, an optional second bolt  90 , along with an optional second nut  92  and washer  94  can be provided, and can be received through the slots  46  and lower hole  88 . However, for some payloads, only the bolt  90  in the upper hole  88  is necessary. Other mechanical fasteners are possible, as long as the mechanical fastener can join the main upright  34  and post receiver  76  in a manner that allows the telescoping post  26  to collapse. 
     The diagonal braces  32  are configured to extend between the telescoping post  26  and the structural base  12  to support the telescoping post  26  and impart rigidity to the corner post assembly  14 . As illustrated herein, the diagonal braces  32  include an elongated rigid body  96  having opposing terminal ends  98  with holes  100  therethough. In one embodiment, the elongated body  96  can be fabricated from ½″ tube stock having flattened ends  98  in which the holes  100  are formed. The holes  100  are configured to receive pins  102  that can define axes of rotation such that the brace  32  has the freedom to rotate about the pins  102 , which may be useful when the corner post assembly  14  is being initially assembled and installed on the base  12 , or when the corner post assembly  14  is being collapsed. The diagonal braces  32  can extend at roughly a  45  angle between the telescoping posts  26  and the attachment plates  30 , although other angles are possible. 
     The diagonal attachment plates  30  are configured to removably attach one of the diagonal braces  32  to the structural base  12  via mechanical fasteners. As shown, one attachment plate  30  can be coupled to the stringer board  22  and the other attachment plates  30  can be coupled to the top deckboard  20 , though in other configurations of the base, the attachment plates  30  may mount to other portions of the base. The diagonal attachment plate  30  can remain coupled to the base  12  in either the upright or collapsed positions of the corner post assembly  14 , but can also be disconnected from the structural base  12  to remove the corner post assembly from the base  12  entirely, or when collapsing the corner post assembly  14  as described in further detail below. 
     As illustrated herein, the diagonal attachment plate  30  includes flat body  104  having an inverted T-shape with one upper hole  106  and two lower holes  108 . The upper hole  106  is aligned with a corresponding hole  100  in the diagonal brace  32 , and the pin  102  is inserted through the aligned holes  100 ,  106  to attach the diagonal brace  32  to the attachment plate  30 . The two lower holes  108  are used in attaching the attachment plate  30  to the structural base  12 , and can receive suitable mechanical fasteners (not shown) such as screws, but may also receive other types of mechanical fasteners such as nails, pins, bolts, rivets, ties, or the like. 
       FIG. 11  is a perspective view of the corner post assembly  14  is in an upright and extended position. In the upright and extended position, the corner post assembly  14  can be fully attached to the structural base  12  (not shown), i.e. the post mount  28  and attachment plates  30  can both be attached to the structural base  12 , and the telescoping post  26  is fully extended, i.e. the post insert  36  is fully extended from the main upright  34 . 
       FIG. 12  is a perspective view of the corner post assembly  14  in an upright and retracted position. In the upright and retracted position, the corner post assembly  14  can be fully attached to the structural base  12  (not shown), i.e. the post mount  28  and attachment plates  30  can both be attached to the structural base  12 , and the telescoping post  26  is fully retracted, i.e. the post insert  36  is fully retracted into the main upright  34 , with the top plate  68  abutting the upper end  40  of the main upright  34 . 
     It is noted that the corner post assembly  14  may have other intermediate positions, not illustrated herein, in between the fully extended and fully retracted positions shown in  FIGS. 11 and 12 . The corner post assembly  14  of the illustrated embodiment may, for example, extend from 33″ to 50.5″ with 2″ increments as defined by the spacing between holes  48 . These dimensions may be particularly appropriate when the structural base  12  uses 2×4 lumber for the deckboards  20  and stringer boards  22 . Further, instead of being discretely adjustable as determined by the spacing of the holes  48 , the length of the corner post assembly  14  can be infinitely adjustable between the fully extended and fully retracted positions shown in  FIGS. 11 and 12 . 
       FIG. 13  is a perspective view of the corner post assembly  14  in a collapsed position. In the collapsed position, the corner post assembly  14  can be collapsed to lie substantially horizontally, with the telescoping post  26  extending laterally from the post mount  28  rather than longitudinally. When collapsed, the corner post assembly  14  can remain partially attached to the structural base  12 . For example,  FIGS. 7-9  show stacked crates  10  in which the corner post assemblies  14  are collapsed, and remain attached to the structural base  12  via the post mounts  28  though the braces  32  are separated from the attachment plates  30 , which remain on the structural base  12 . Alternatively, the corner post assembly  14  can be fully removed from the structural base  12  when collapsed, as shown for example in  FIG. 13 ; in this case, the attachment plates  30  can be removed from the structural base  12  and can remain coupled with the diagonal braces  32 . It is noted that the diagonal braces  32  do not extend past the telescoping post  26  in the collapsed position, which can help protect the diagonal braces  32  from damage. Also in the collapsed position, the telescoping post  26  can be extended, retracted, or in some intermediate position in between. 
       FIGS. 14-16  are close-up views showing the movement of the corner post assembly  14  from the upright position to the collapsed position. Initially, when in the upright position, the main upright  34  is received with the lower end  42  engaging the upper end  84  of the post receiver  76 , and the slotted tab  44  which receives the connecting bolt  90 , abutting the top of the mounting plate  72 . The telescoping post  26  is locked securely in place when the locator tabs  86  extend into the lower end  42  of the main upright  34  and the diagonal braces  32  are connected to the structural base  12  (see, for example,  FIG. 1 ). 
     To collapse the corner post assembly  14 , the diagonal braces  32  are disconnected, either by disconnecting them from the attachment plates  30 , which may remain on the structural base  12 , or by disconnecting the attachment plates  30  from the structural base  12 . Then, the main upright  34  is moved or pulled upwardly away from the post receiver  76 , as shown in  FIG. 15 . As the main upright  34  moves, the bolt  90  which fastens the main upright  34  to the post receiver  76  slides within the aligned slots  46  on the tabs  44 , which limits the distance the main upright  34  can travel away from the post receiver  76  and ensures that the main upright  34  is not fully separated from the post receiver  76 . The bolt  90  can optionally be loosened before moving the main upright  34  to permit the main upright  34  to slide a little easier. If a second bolt is in place of a heavy payload, the second bolt can be removed before collapsing the corner post assembly  14 . 
     As shown in  FIG. 15 , the lower end  42  of the main upright  34  eventually clears the locator tabs  86  on the post receiver  76 . The slot  46  can be configured such that the bolt  90  reaches the bottom end of the slot  46  when the lower end  42  is clear of the locator tabs  86 . Once main upright  34  is free of the locator tabs  86 , the main upright  34  (and thus the entire telescoping post  26 ) can be rotated about the bolt  90  to lie in a generally lateral or horizontal orientation, as shown in  FIG. 16 . 
     The crate  10  can be initially assembled and collapsed in accordance with the following methods. The sequence of steps discussed is for illustrative purposes only and is not meant to limit the method in any way as it is understood that the steps may proceed in a different logical order, additional or intervening steps may be included, or described steps may be divided into multiple steps, without detracting from the invention. 
     To initially assemble the crate  10 , holes for the post mount  28  can be pre-drilled into each corner of the structural base  12 . The corner post assemblies  14  are connected to each corner of the structural base  12  using the carriage bolts  80 . Before or after connection to the base  12 , the height of the corner post assemblies  14  can optionally be adjusted. The diagonal braces  32  are then attached to the structural base  12  using the attachment plates  30  and screws that are drilled directly into the sides of the structural base  12 . The assembled crate  10  is shown in  FIGS. 1-3 . 
     When assembled, the crates  10  are stackable by placing the open lower end  85  of the post receivers  76  of one crate  10  on the locator pins  70  of the corner post assemblies  14  of another crate  10 , as shown in  FIGS. 4-6 . Also when assembled, the corners posts  14  of the crate  10  are collapsible when still attached to the structural base  12 , as shown in  FIGS. 7-9 . Collapsing the corner post assemblies  14  allows them to lay essentially flat, and provides the ability to stack multiple collapsed crates  10  on top of one another. In addition to locking the telescoping post  26  in place when upright, the locator tabs  86  are adapted to nest into the post mount  28  of another corner post assembly  14  for securely stacking the collapsed crates  10 . The locator tabs  86  can guide an upper crate  10  in the stack into proper alignment with a lower crate  10  and securely nest within the open lower end  85  of the post receiver  76  on the lower crate  10 . 
     To collapse an assembled crate  10 , the pins  102  attaching the diagonal braces  32  to the attachment plates  30  are removed, and the braces  32  are folded toward the telescoping posts  26 . Alternatively, the attachment plates  30  can be initially removed from the base  12 , leaving them attached to the braces  32  as they are folded closed. The corner post assembly  14  is then collapsed according to the steps described above with reference to  FIGS. 14-16 . 
     In an alternative embodiment, instead of having rigid bodies  96 , the diagonal braces  32  can comprise flexible straps or cables which allow the corner post assemblies  14  to be collapsed without disconnecting the braces  32 . When upright, the cables resist racking in tension as well as act as a support cable when the crate is carrying a payload and stacked on top of another crate. 
       FIG. 17  shows a collapsible, stackable, and returnable crate  110  according to a second embodiment of the invention. There are three primary component groups of the crate  110 , including a structural base  112 , collapsible corner post assemblies  114 , and various mechanical fasteners, described in more detail below. For purposes of description related to the figures, the terms “upper,” “lower,” “vertical,” “horizontal,” and derivatives thereof shall relate to an orientation of the crate  110  as shown in  FIG. 17 , with a lower side of the crate facing and resting on a surface (not shown). However, it is to be understood that the invention may assume various alternative orientations, except where expressly specified to the contrary. 
     The structural base  112  defines a support surface for a payload. The structural base  112  can be preferably fabricated from wood, while the corner post assemblies  114  can be preferably fabricated from metal, such as steel. This combination of materials offers a reduced-cost, collapsible crate that is robust enough to support large payloads, and can further be stacked when assembled with at least one other crate  110  as shown in  FIG. 18  or stacked when collapsed with at least one other crate  110  as shown in  FIG. 19 . 
     The structural base  112  may be customized based on the payload. The structural base  112  of the illustrated embodiment is customized for a motorcycle, and includes a plurality of slats that are mechanically fastened to each other to create the structural base  112 . The slats include a plurality of bottom deckboards  118  and a plurality of top deckboards  120  that are mechanically fastened to a plurality of stringer boards  122  running between the deckboards  118 ,  120 . Blocks  124  can also be provided between and mechanically fastened to the deckboards  118 ,  120  and stringer boards  122 . Mechanical fasteners such as nails, screws, pins, bolts, rivets, ties, or the like can be used for the mechanical attachments of the base  112 . Furthermore, other joining methods of assembling the base  112  can also be used. 
     As with the first embodiment, other embodiments of the structural base  112  are possible, including different configurations of the slats than that shown herein. While a customized base  112  for shipping a motorcycle is shown herein, the base on which the corners posts  114  are mounted can be any type of base. For example, in one embodiment, the structural base  112  can be a pallet. Furthermore, the corner post assemblies  114  are adapted to be transferred between different types of bases, as described in further detail below. Also, while it is preferred that the structural base  112  be manufactured from a low-cost material such as wood, in other embodiments of the crate  110 , the structural base  112  can be manufactured using a variety of materials including wood, plastic, composite, metal, fiberglass, wood-plastic composite, or some combination of these materials. In some applications of the crate  110 , it is preferred that the structural base  112  be constructed of a material that is lower cost than the material used for the corner post assemblies  114 . 
       FIG. 20  is an exploded view of a corner portion of the crate  110  of  FIG. 17 , and shows one of the corner post assemblies  114  exploded from a corner of the structural base  112 . The collapsible corner post assemblies  114  are upright supports configured to provide lateral protection to the payload, and are adapted to allow multiple crates to be stacked when assembled or when collapsed as shown in  FIGS. 18-19 . The corner post assemblies  114  can include a post  126  and a post mount  128  configured to couple the post  126  to the structural base  112 . 
     The various components of the corner post assembly  114  can be attached using mechanical fasteners; alternatively, some of the various components can be welded, or otherwise attached. While the corner post assemblies  114  can be preferably fabricated from metal, and more particularly from steel, in other embodiments, the corner post assemblies  114  can be manufactured using a variety of materials including metal, plastic, composite, wood, fiberglass, wood-plastic composite, or some combination of these materials. In some applications of the crate  110 , it is preferred that the corner post assemblies  114  be constructed of a material that is more robust than the material used for the structural base  112 , so that the corner post assemblies  114  can withstand the repeating stacking and collapsing required of the collapsible, stackable, and returnable crate  110 . 
     In the illustrated embodiment, the post  126  is a single post having a fixed length; in other embodiments of the crate  110 , the post  126  can be a telescoping post having an adjustable length, such as shown for the corner post assembly  14  of the first embodiment. 
     The post  126  includes an elongated tubular body  138  defining an at least partially hollow interior and having an open upper end  140  and an open lower end  142  which couples with the post mount  128 . Slots  144 , only one of which is visible in  FIG. 20 , are formed near the lower end  142  of the tubular body  138  in opposing sides of the post  126 , and maybe angled in order to guide the post  126  between an upright position and a collapsed position while also clearing the post mount  128 . In the embodiment shown herein, the slots  144  have a dogleg shape, with a generally vertically-extending upper slot portion  146  and a lower slot portion  148  which extends at an angle to the upper slot portion  146  but is otherwise continuous with the upper slot portion  146 . 
       FIG. 21  is a close-up view of the top the corner post assembly  114 . The upper end  140  includes at least one toothed upper edge  150 . The toothed upper edge  150  is adapted to grip the bottom of the base  112  of another crate  110  for securely stacking the crates  110  (see, for example,  FIG. 18 ). As illustrated, the post  126  is rectilinear in shape, and includes two toothed edges  150  on opposing sides of the upper end  140 , and two untoothed edges  152  joining the toothed edges  150  Alternative configurations of the upper end  140  are possible as long as the crates  110  can be securely stacked, such as, but not limited to the entire upper edge of the post  126  having teeth, or a non-toothed configuration, such as the locator pin  70  shown in the first embodiment. 
       FIG. 22  is a close-up view of an interface between the stacked crates  110  shown in  FIG. 18 , in particular the interface between one corner post assembly  114  of the lower crate  110  and the base  112  of the upper crate  110 . The toothed edges  150  of the corner post assemblies  114  of the lower crate  110  grip the base  112  of the upper crate  110  for secure stacking of the crates  110 . In one embodiment where the post  126  is metal, such as steel, and the base  112  is wood, the toothed edges  150  of the lower post  126  can dig into the wood of the base  112 . 
     Referring back to  FIG. 20 , the post mount  128  includes a corner bracket  170  having a vertical mounting plate  172  and a horizontal mounting plate  174  coupled with a post receiver  176  configured to receive the post  126 . The mounting plates  172 ,  174  are configured to mount to the structural base  112 , thereby mounting the post  126  to the structural base  112 . Specifically, the vertical mounting plate  172  is coupled to one of the stringer boards  122  and one of the adjacent blocks  124 , and the horizontal mounting plate  174  is mounted to one of the top deckboards  120 , though in other configurations of the base  112 , the plates  172 ,  174  may mount to other portions of the base  112 . 
     Each plate  172 ,  174  includes at least one hole  178  configured to receive a mechanical fastener, illustrated herein as a carriage bolt  180 , used to secure the plates  172 ,  174  to the structural base  112 . Other mechanical fasteners are possible, as long as the mechanical fastener can temporarily join the mounting plates  172 ,  174  to the base  112  to allow the post mount  128  to be removed from the structural base  112  as needed. As illustrated, each plate  172 ,  174  includes two holes  178  that are spaced and offset from each other. Offsetting the holes  178  distributes the forces from the payload over a greater area within the base  112 . In general, the holes  178  can be aligned vertically, aligned horizontally, and/or offset depending on the application and constraints. Also, in the illustrated embodiment, two holes  178  are provided in each plate  172 ,  174 , though the number can vary in other embodiments of the corner post assembly  114 . 
     The post mount  128  can be configured as a universal mount, such that the corner post assemblies  114  can be attached to any base, not just the structural base  112  illustrated herein. The corner bracket  170  can be sized to accommodate attaching the corner post assembly  114  to a base  112  having boards or slats in a range of sizes. The mounting plates  172 ,  174  and post receiver  176  can be fabricated from one flat plate that is stamped to define the corners of the post receiver  176  and the corner between the post receiver  176  and the horizontal mounting plate  174 . Alternatively, the plates  172 ,  174  and post receiver  176  can be fabricated separately and welded or otherwise attached to form the post mount  128 . 
     The post receiver  176  includes a U-shaped body defining an at least partially hollow interior and having an open upper end  184  which receives with the lower end  142  of the post  126 , and an open lower end  186  configured to meet the base  112 , alongside the horizontal mounting plate  174 . The U-shaped body is further open at a side that extends between the upper and lower ends  184 ,  186 , 
     At least one pair of holes  188  is formed along the same opposing sides of the post receiver  176  as the slots  144 . The holes  188  are used for the connection between the post  126  and post mount  128 . In the illustrated embodiment, the bodies of the post  126  and post receiver  176  can be rectilinear in shape, and the body of the post  126  can nest within the post receiver  176 . Also, while the bodies are shown as having a rectilinear cross-section, other cross-sectional shapes are possible. 
     The tubular body  138  can be slidingly received in the post receiver  176  to couple the post  126  with the post mount  128  and also selectively allow the post  126  to collapse, as described in further detail below. To fix the post  126  on the post receiver  176 , a mechanical fastener such as a bolt  190  and a nut  192  which can be threaded onto the bolt  190  can be used; optionally, a washer  194  can also be provided. In the present embodiment, the bolt  190  is received by the holes  188  in the post receiver  176  and the slots  144  in the post  126 . The bolt  190  and slots  144  form a pin-in-slot joint between the telescoping post  126  and the post mount  128 , which has two degrees of freedom such that the slots  144  can slide relative to and pivot about the bolt  190 , and therefore the post  26  can slide and pivot relative to the post mount  128 . Other joints permitting translational and rotating movement between the post  126  and post mount  128  can also be used. Other mechanical fasteners are possible, as long as the mechanical fastener can join the post  126  and post receiver  176  in a manner that allows the post  126  to collapse. 
       FIGS. 17-18  show the crate  110  with the corner post assemblies  114  in an upright position. In the upright position, the corner post assemblies  114  can be fully extended from structural base  112 , i.e. the posts  126  can extend vertically upwardly from the corners of the structural base  112 .  FIG. 19  shows the crate  110  with the corner post assemblies  114  in a collapsed position. In the collapsed position, the corner post assemblies  114  can be collapsed to lie substantially horizontally, with the posts  126  extending laterally from the post mounts  128  rather than longitudinally. When collapsed, the corner post assemblies  114  can remain attached to the structural base  112 .  FIG. 19  shows stacked crates  110  in which the corner post assemblies  114  are collapsed, and remain attached to the structural base  112  via the post mounts  128 . 
       FIGS. 23-24  are close-up views showing the movement of the corner post assembly  114  from the upright position to the collapsed position. Initially, when in the upright position, the post  126  is received with the lower end  142  within the post receiver  176  and engaging the base  112 , and the slots  144  receiving the connecting bolt  190 . When the post  126  is upright and the bolt  190  is at the top of the slots  144 , the back of the post receiver  176  locks the post  126  vertically. 
     To collapse the corner post assembly  114 , the post  126  is moved or pulled upwardly away from the post receiver  176 . As the post  126  moves, the bolt  190  slides within the aligned slots  144  on the lower end  142  of the post  126 , which limits the distance the post  126  can travel away from the post receiver  176  and ensures that the post  126  is not fully separated from the post receiver  176 . The bolt  190  can optionally be loosened before moving the post  126  to permit the post  126  to slide a little easier. As the post  126  is lifted upwardly, the bolt  190  passing through the angled slots  144  forces the post  126  forward, spacing the lower end  142  of the post  126  away from the back of the post receiver  176  and eventually allowing the post  126  to clear the back of the post receiver as it is rotated about the bolt  190  to lie in a generally lateral or horizontal orientation, as shown in  FIG. 24 . 
     The crate  110  can be initially assembled and collapsed in accordance with the following methods. The sequence of steps discussed is for illustrative purposes only and is not meant to limit the method in any way as it is understood that the steps may proceed in a different logical order, additional or intervening steps may be included, or described steps may be divided into multiple steps, without detracting from the invention. 
     To initially assemble the crate  110 , holes for the post mount  128  can be pre-drilled into each corner of the structural base  112 . The corner post assemblies  114  are connected to each corner of the structural base  112  using the carriage bolts  180 . The assembled crate  110  is shown in  FIG. 17 . 
     When the crates  110  are assembled with the corner post assemblies  114  attached to the base  112 , the crates  110  are stackable by placing the base  112  of one crate  110  on the upper ends  140  of the corner post assemblies  114  of another crate  110 , as shown in  FIG. 18 . Also when assembled, the corners posts  114  of the crate  110  are collapsible when still attached to the structural base  112 , as shown in  FIGS. 19 and 24 . Collapsing the corner post assemblies  114  allows them to lay essentially flat, and provides the ability to stack multiple collapsed crates  110  on top of one another. To collapse an assembled crate  110 , the post  126  is folded toward the base  112  according to the steps described above with reference to  FIGS. 23-24 . 
       FIGS. 25-27  show a corner post assembly  214  for a crate according to a third embodiment of the invention. A crate comprising the corner post assembly  214  can include the same three primary component groups, including a structural base, multiple corner post assemblies  214 , and various mechanical fasteners, as described for any of the embodiments of crates discussed herein. It is understood that the corner post assembly  214  can, for example, be used for the crate  10  or crate  110  of the first or second embodiments in place of the corner post assemblies  14 ,  114  discussed for those embodiments. Furthermore, the corner post assembly  214  can be adapted to be transferred between different types of bases for different types of crates. 
     The corner post assembly  214  is an upright support configured to provide lateral protection to a payload, and is further adapted to allow multiple crates to be stacked when assembled or when collapsed, as shown in  FIGS. 25 and 26-27 , respectively. The corner post assembly  214  can include a post  226  and a post mount  228  configured to couple the post  228  to the structural base of a crate. In  FIGS. 25-27 , break lines are used to shorten the post  226  in order to allow an enlarged view of the corner post assembly  214  to be shown. 
     The various components of the corner post assembly  214  can be attached using mechanical fasteners; alternatively, some of the various components can be welded, or otherwise attached. While the corner post assembly  214  can be preferably fabricated from metal, and more particularly from steel, in other embodiments, the corner post assembly  214  can be manufactured using a variety of materials including metal, plastic, composite, wood, fiberglass, wood-plastic composite, or some combination of these materials. In some applications, it is preferred that the corner post assembly  214  be constructed of a material that is more robust than the material used for the structural base, so that the corner post assembly  214  can withstand the repeating stacking and collapsing required of a collapsible, stackable, and returnable crate. 
     The post  226  includes at least one elongated tubular body  238  defining an at least partially hollow interior and having an upper end  240  and a lower end  242  which couples with the post mount  228 . The upper end  240  may have a locator pin as described for the first embodiment, a toothed upper edge as described for the second embodiment, or neither, as shown herein. The post  226  can be a single post having a fixed length; alternatively, the post  226  can be a telescoping post having an adjustable length, such as shown for the corner post assembly  14  of the first embodiment. 
     The post mount  228  includes a corner bracket  270  configured to be attached to the corner of a structural base, thereby mounting the post  226  to the structural base. The bracket  270  can have a first U-shaped receiver  272  and a second U-shaped receiver  274  joined in an L-shape and coupled with a post receiver  276  configured to receive the post  226 . The bracket  270  can be attached to a crate base by one or more mechanical fasteners or another joining method. 
     The U-shaped receivers  272 ,  274  are configured to hold stringer boards that create a frame for the structural base. This allows for a structural base without bottom deck boards, which makes the use of a pallet jack much easier. The U-shaped receivers  272 ,  274  can optionally further comprise a tooth system to attach the corner post assembly  214  to the base. As shown in the illustrated embodiment, the U-shaped receivers  272 ,  274  have triangular or tooth-shaped cutouts  278  that are pushed in so when the stringer boards for the base are forced into the U-shaped receivers  272 ,  274 , the or tooth-shaped cutouts  278  bite into the stringer boards and lock them into place, eliminating the need for additional mechanical fasteners. 
     The post receiver  276  includes a U-shaped body defining an at least partially hollow interior and has an open side  282  and an open upper end  284  which receives with the lower end  242  of the post  226 . In the illustrated embodiment, the bodies of the post  226  and post receiver  276  can be rectilinear in shape, and the body of the post  226  can nest within the post receiver  276 . Also, while the bodies are shown as having a rectilinear cross-section, other cross-sectional shapes are possible. 
     The post  226  can be connected with the post mount  228  by a pin-in-slot joint, whereby the tubular body  238  can be slidingly received in the post receiver  276  in an upright or assembled position as shown in  FIG. 25 , and also selectively allow the post  226  to collapse, as described in further detail below, as shown in  FIGS. 26-27 . Other joints permitting translational and rotating movement between the post  226  and post mount  228  can also be used. 
     First slots  286  are formed in opposing sides of the post receiver  276 . A second slot  288  is formed in the first U-shaped receiver  272 , and is at least partially coextensive with the first slots  288 . The slots  286 ,  288  can be elongated generally in the lengthwise or vertical direction of the post  226 . 
     To fix the post  226  on the post receiver  276 , a mechanical fastener or pin  290 , such as a bolt and a nut which can be threaded onto the bolt, can be used, and extends through the post  226  and through the slots  286 ,  288 . The pin  190  and slots  286 ,  288  form the pin-in-slot joint, which has two degrees of freedom such that the post  226  can slide and pivot relative to the post mount  228 . The first slots  286  are closed at the upper and lower ends thereof to prevent the post  226  from being entirely separated from the post receiver  276  as the post  226  is moved relative to the post mount  228 , while the second slot  288  is open at an upper end thereof, which allows the pin  290  to drop below the upper edge of the bracket  270 . 
     The post mount  228  further comprises a post pocket  292  configured to nest with another corner post assembly  214  on another crate for securing stacking the crates. As illustrated, the post pocket  292  is flared outwardly and has a wide base  294 . For example, the base  294  can be wider than the upper portion of the pocket  292  and the post receiver  276 . The flared shape of the pocket  292  can help guide an upper crate in the stack into proper alignment on top of a lower crate. Crates are stackable by placing the pockets  292  of one crate on the upper ends  240  of the posts  226  of another crate. The wide base  294  of the pockets  292  also eases stacking crates when the corner post assemblies  214  are collapsed. When collapsed, crates are stackable by resting the wide base  294  of the pockets  292  of one crate on top of the post mounts  228  of another crate. Alternative configurations of the post pocket  292  are possible, as long as the crates can be stacked when assembled or collapsed. 
       FIG. 25  shows the corner post assembly  214  in an upright position. In the upright position, the corner post assembly  214  can be fully extended from structural base, i.e. the posts  226  can extend vertically upwardly from the corner of the structural base. The post  226  is received with the lower end  242  within the post receiver  276 , and the pin  290  is at or closer to the bottom of the aligned slots  286 ,  288 . The back of the post receiver  276  can lock the post  226  vertically. 
       FIGS. 26-27  show the corner post assembly  214  in a collapsed position. In the collapsed position, the corner post assembly  214  can be collapsed to lie substantially horizontally, with the post  226  extending laterally from the post mount  228  rather than longitudinally. When collapsed, the corner post assembly  214  can remain attached to the structural base. Further, crates can be stacked when the corner post assemblies  214  are collapsed, which can remain attached to the structural base via the post mounts  228 . 
     To collapse the corner post assembly  214 , the post  226  is moved or pulled upwardly away from the post receiver  276 . As the post  226  moves, the pin  290  slides within the aligned slots  286 ,  288 , which limit the distance the post  226  can travel away from the post receiver  276  and ensures that the post  226  is not fully separated from the post receiver  276 . The pin  290  can optionally be loosened before moving the post  226  to permit the post  226  to slide a little easier. As the post  226  is lifted upwardly, the pin  290  eventually clears the slot  288  in the first U-shaped receiver  272 , and the post  226  is rotated to lie in a generally lateral or horizontal orientation, as shown in  FIG. 26 . 
     As shown in  FIGS. 26-27 , when the corner post assembly  214  is collapsed, the upper edge  284  of the post receiver  276  can be substantially flush which the side of the tubular body  238  to enable crates to be stacked. Alternatively, the upper edge  284  of the post receiver  276  can be raised relative to the side of the tubular body  238  for nesting further into the post pocket  292  when collapsed crates are stacked. 
     It is noted that any of the crate embodiments disclosed herein can be provided as a complete crated solution, including a structural base, collapsible corner post assemblies, and various mechanical fasteners. Alternatively, the corner post assemblies  14 ,  114 ,  214  can be packaged as a universal kit which is attachable to any base or pallet. Still further, a rental system is contemplated in which a whole crate or just corner post assemblies are rented on a per use basis. 
     It is further noted that while various mechanical fasteners are discussed herein for joining particular components of the crate embodiments disclosed herein, it is understood that alternative mechanical fasteners such as screws, pins, bolts, rivets, ties, nails, or the like can be used for the mechanical attachments described, unless otherwise noted. Furthermore, other methods of joining the components of the crate embodiments disclosed herein can be used, including, but not limited to, crimping, welding, soldering, brazing, taping, gluing, cementing, or the use of other adhesives, unless otherwise noted. 
     It is further noted that while the crate embodiments disclosed herein may be described as being returnable, any of the crate embodiments disclosed herein can also be configured for one-way use. A returnable crate can, for example, be made from more heavy duty components than a one-way crate, such as having thicker steel for the post mounts, larger tube sizes for the posts, and/or bolting the corner post assemblies to the base with a nut and washer instead of simply screwing the corner post assemblies to the base with deck screws or lag screws. 
     The embodiments of the invention disclosed herein provide for a collapsible and stackable crate that improves over prior crate systems. The crate provides a strong, stackable system that can be folded flat for storage or shipping. The corner post assemblies provide the flexibility to be used with any size base or pallet configuration. The corner post assemblies are collapsible, which allows them to lay flat &amp; provides the ability of stacking systems on top of one another. In some embodiments of the invention, the corner post assemblies further have an adjustable length to accommodate for differently-sized payloads and/or stacking heights. The crate is durable and at least some embodiments of the invention can offer a conveniently returnable system that can be reused many times. The crate can be preferably constructed from both wood and steel, which offers both affordability and strength. 
     While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation. Reasonable variation and modification are possible with the scope of the foregoing disclosure and drawings without departing from the spirit of the invention which, is defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise.