Abstract:
A reusable and returnable container for holding product therein during shipment and subsequently being returned without product comprises a body having at least two opposed side structures, collapsible dunnage operably connected to the side structures, and a dunnage erection biaser operably connected to one of the side structures. The force needed to erect the dunnage is minimized due to the dunnage erection biaser. The dunnage erection biaser, in one embodiment is a pair of torsion springs. However, the biaser may be any elastic or non-elastic device to facilitate erection of collapsed dunnage.

Description:
FIELD OF THE INVENTION 
   The present invention relates generally to shipping containers used to ship products, and more specifically to collapsible containers which are returnable in an empty state for reuse. 
   BACKGROUND OF THE INVENTION 
   Returnable and reusable containers are utilized by manufacturers to ship a variety of different products to end users, such as assembly plants. For example, an automobile assembly plant utilizes parts from a number of different parts manufacturers or suppliers. These suppliers ship their respective parts to the assembly plant in reusable containers, and the parts are then removed from the containers, assembled into a finished product, and the empty containers are then returned to the parts suppliers for use in subsequent shipments. 
   The return and reuse of empty containers results in a substantial cost savings for the supplier and/or the end manufacturer or assembler because reuse reduces the number of new containers which must be purchased. Furthermore, the returned containers alleviate the assembly plant&#39;s task and associated costs with storing, destroying, or otherwise disposing of the containers. 
   While returnable and reusable containers reduce costs by eliminating the need to constantly purchase new containers and reduce disposal costs, it may still be relatively costly to provide for their return shipment. The shipping rate for return shipment of empty containers is typically based upon the volume of the container and upon the number of containers which might be situated in a return vehicle. Historically, there was a one-to-one (1:1) return-to-shipment ratio because an empty container occupied the same shipping space or volume as a full container. Therefore, there was not much of a shipping cost savings when returning empty reusable containers even though empty containers weighed less. 
   Furthermore, the cost of storing conventional reusable containers may further reduce the other economic benefits they offer because empty containers also require the same warehouse or storage space as full containers. Container storage may be necessary at the plant before a return shipment can be arranged. Similarly, the supplier will store containers on site so as to have them ready for shipment. Storage space is valuable and may be limited, and it is usually desirable to utilize the space for something other than bulky, empty containers waiting to be shipped or returned. Therefore, the economic benefits provided by currently available reusable containers is reduced by the cost, both to the end user assembly plant and supplier, of return shipment and pre-return or post-return storage space requirements. 
   Some currently available reusable containers have addressed such problems by being collapsible into a smaller size or volume to thereby require less space when returned or stored. For example, some available reusable containers are collapsible into a volume essentially one-third (⅓) or one-fourth (¼) of their volume when shipped full of product. This provides a three-to-one (3:1) or four-to-one (4:1) return-to-shipment ratio, and thus, provides a substantial savings in return shipment costs. That is, a truck returning the containers to the originating site can carry three or four times the number of empty, collapsed containers as full containers. Additionally, collapsed, stored containers require substantially less storage space. 
   While such containers address the issue of return shipment and storage costs, they still have certain drawbacks. For example, for the containers to be collapsible, it is necessary to utilize separate dunnage elements, such as partitions or separating structures, in the container during shipment. Dunnage elements are used for separating and protecting the products shipped in the container. The dunnage elements must be handled separately from the container during shipment and return. That is, when the container has been assembled into an erected form for shipment and dunnage elements are to be utilized, the dunnage must be separately inserted and secured within the container. Subsequently, prior to return shipment, any dunnage elements utilized within the container must be detached and removed therefrom before the container can be collapsed into the smaller, returnable shape. The dunnage elements are then discarded or otherwise disposed of by the assembly plant, further adding to the plant&#39;s overall cost for the shipment. 
   Furthermore, the supplier incurs additional costs by constructing or acquiring new dunnage elements each time the returned container is reused. Additionally, the labor costs associated with constructing and installing dunnage elements in a container, and the additional labor for collapsing, removing and disposing of the dunnage elements after shipment, further increases the overall cost of shipping product utilizing conventional containers. Therefore, even with existing collapsible, returnable containers, high shipping costs may be incurred on both ends, i.e., by the supplier who constantly acquires new dunnage elements and by the assembly plant which constantly must dispose of the old dunnage elements or pay to have those dunnage elements returned with the container. 
   Moreover, dunnage elements, depending on the size of the container, may be heavy, and as such, the assembly of the dunnage elements to accept a product can be physically stressful for the worker and may lead to job related injuries. Job related injuries increase costs. Additionally, because someone must physically assemble the dunnage, the dunnage elements and the containers have been limited in size and weight in accordance with what an average worker can physically and safely erect. 
   Access to the product in the containers is also a particular concern. Specifically, in the automotive industry, containers full of product are positioned on an assembly line adjacent to a work area which is associated with a particular product to be installed on a manufactured vehicle. For example, at a line position or station where interior door panels are installed onto a door, a container full of door panels is positioned at the station for access by the line worker. The product or part is taken directly from the container and is used on the line. However, access to some existing containers may be difficult when removing a parts to install. Because, a line worker only has a certain amount of time to install a part, any delay in accessing a part is undesirable. Furthermore, the repetitive motion of accessing parts to install on a vehicle from some containers can be difficult or straining to line workers since it must be done many times during a shift. Likewise, repetitively having to assemble or erect a dunnage structure can be wearisome for workers. 
   Some existing products have recognized some of these needs and have provided returnable, collapsible containers with integral dunnage. For example, U.S. Pat. Nos. 5,725,119; 6,062,410; 6,230,916 and 6,540,096, all of which are fully incorporated by reference herein, illustrate various containers and structures. While such products have provided many desirable benefits, such as reducing overall container and shipping costs, improvements are still desirable. 
   Accordingly, it is an objective of the present invention to reduce the force required to erect a dunnage structure in a returnable and reusable container. 
   It is further an objective of the present invention to allow larger or heaver dunnage systems to be used in returnable and reusable containers without increasing the required lifting force that must be applied to erect such dunnage. 
   It is also an object of the present invention to allow for the use of larger collapsible containers with more dunnage to allow shipment of more parts than heretofore possible. 
   It is further an objective of the present invention to reduce the likelihood of on the job injuries related to the assembly or erection of a dunnage structure within a returnable and reusable container. 
   These objectives and other objectives will become more readily apparent from the further description of the invention below. 
   SUMMARY OF THE INVENTION 
   The above objectives and other objectives are addressed by the present invention, which provides a container, typically a reusable and returnable container, that has a body having at least two opposed side structures, collapsible dunnage extending between the two opposed side structures, and a dunnage erection biaser operably connected to one of the side structures. The force needed to erect the dunnage for use is minimized through use of the dunnage erection biaser. 
   The dunnage erection biaser may comprise an elastic or non-elastic device. The biaser may be comprised of rubber or it may be one or springs, e.g., torsion springs or leaf springs, that facilitate erection of the container and/or dunnage. Alternatively, the dunnage erection biaser may use other types of springs or other devices such as sheaves, pulleys, block and tackles, counterweights, etc., singularly or in combination with one another. In any configuration, the dunnage erection biaser, along with the dunnage, remains with the container when the empty container is returned to be loaded again. 
   In one preferred embodiment, the container comprises a body having at least two opposing and moveable side walls. The side walls are configured for being selectively moved into an erected position for product shipment and then moved into a collapsed position for reducing the size of the empty container for return shipment. In one embodiment of the invention, the return-to-shipment volume ratio is approximately 2:1. 
   For retaining product within the container, collapsible dunnage spans between at least two side structures. In one embodiment, the dunnage is movable to an erected position for receiving product when the side walls and frame are erected. The dunnage also moves to a collapsed position in the container body when the side walls and frame are collapsed, so that the dunnage remains with the container when returned. In that way, the dunnage in the container is also reusable, reducing dunnage replacement costs, and also reducing and/or eliminating labor costs associated with handling and discarding used dunnage from a container and assembling new dunnage prior to the container being loaded with product and shipped. 
   In a preferred embodiment, the container has an open side for horizontal loading of product into the dunnage. The open side is in alignment with the dunnage for providing access to the dunnage and product within the dunnage from the side of the container. The product in the container may thus be transferred into and out of the container easily and efficiently in a process known in the art as horizontal loading. The present invention is particularly useful for assembly line use as product in the container may be removed and transferred to an assembly line in one smooth movement. Unnecessary lifting of the product is reduced and/or eliminated to further assist an assembly line worker or other person using the shipped products. 
   In a preferred embodiment, a frame is incorporated into the container. A portion of the frame may be pivotally coupled with respect to the remainder of the frame so an upper portion of the frame may be moved between a collapsed and erected position. Pivotal joints are biased with a dunnage erection biaser, e.g., a torsion spring, which minimizes the force needed to erect one of the side structures and associated dunnage of a collapsed container. A latching structure coupled to the body secures the frame in an erected position. Preferably, two opposing latching structures are utilized to maintain the upper portion of the frame in an erect condition. The latching structures may be any known in the art. 
   In accordance with another aspect of the present invention, the dunnage comprises a plurality of pouches which are coupled at their ends to opposing side structures. Specifically, rails may extend along the upper edges of opposed side structures and the dunnage pouches are coupled to the rails. In one embodiment, the dunnage pouches are slidably coupled to the rails. The pouches may be sealed at their top, or be open at the top, to allow top and/or side access to products within the pouches. 
   Due at least in part to the dunnage erection biasers, the present invention reduces the force needed to erect the containers and attached dunnage. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with a general description of the invention given below, serve to explain the principles of the invention. 
       FIG. 1  is a perspective view of a preferred embodiment of the collapsible container of the invention, showing the container erected with a dunnage structure in an erected position for holding product for shipment or storage; 
       FIG. 2  is a perspective view of the collapsible container of  FIG. 1 , showing the frame and dunnage being collapsed; 
       FIG. 3A  is a side elevational view of the container of  FIG. 1  showing the frame collapsed; 
       FIG. 3B  is a side elevational view of the container of  FIG. 1  showing the rear wall collapsed; 
       FIG. 3C  is a front elevational view of the container of  FIG. 1  showing the side walls being collapsed; and 
       FIG. 3D  is a front elevational view of the container of  FIG. 1  in a collapsed position. 
   

   DETAILED DESCRIPTION 
     FIG. 1  shows a container  10  having a base  12  having a bottom portion  14  and three fixed, upstanding vertically oriented wall portions  16   a ,  16   b  and  16   c  extending upwardly from the perimeter of the bottom portion  14  of the base  12 . A rear wall  18   b  and side walls  18   a ,  18   c  are hingedly connected to the vertically oriented wall portions  16   b  and  16   a ,  16   c  of the base  12 , respectively. Side wall  18   a  is hingedly or pivotally joined to the wall portion  16   a  of the base  12  with a hinge pin  20   a  so that the side wall  18   a  may move or pivot from a collapsed position shown in  FIG. 3D  to an erected position shown in  FIG. 3A . Similarly, rear wall  18   b  is hingedly or pivotally joined to the wall portion  16   b  of the base  12  with a hinge pin  20   b  (see  FIG. 3A ) so that the rear wall  18   b  may move or pivot from a collapsed position shown in  FIG. 3D  to an erected position shown in  FIG. 1 . Lastly, side wall  18   c  is hingedly or pivotally joined to the wall portion  16   c  of the base  12  with a hinge pin  20   c  so that the side wall  18   c  may move or pivot from a collapsed position shown in  FIG. 3D  to an erected position shown in  FIG. 3A  Although one type of hinge is illustrated to connect the rear and side walls  18   b ,  18   a ,  18   c  to the base  12 , any other type of hinge or connection may be used as desired. 
   The combination of the wall portion  16   a  of the base  12  and the side wall  18   a  make up a side wall structure  22   a . Similarly, the wall portion  16   c  of the base  12  and the side wall  18   c  make up another side wall structure  22   c  on the opposite side of the container  10 . Lastly, the rear or back wall portion  16   b  of the base  12  and the rear wall  18   b  make up a rear wall structure  22   b.    
   The container  10  may also have a top and a side structure opposite rear wall structure  22   b  (neither shown). The base  12  may be a pallet-type base having a plurality of slots or grooves  15  formed therein for receiving the forks of a lift truck or any other configuration. Although one configuration of base  12  is illustrated, other types or configurations of bases may be used in accordance with the present invention. 
   In the embodiment of the invention illustrated, the base  12  and walls  18   a – 18   c  make up the overall body  20  of the container  10 . Therefore, the embodiment of the container illustrated in  FIG. 1  has a box-like shape. Container.  10 , and particularly the body  20  of the container  10 , is made of a suitably rugged material, such as a strong, durable plastic, metal, or chipboard, or the like. Containers which may be adapted or configured to include various invention features in accordance with the aspects of the present invention, are available from Ropak Corporation of Georgetown, Ky. A Ropak collapsible container may be retrofitted in accordance with the principles of the present invention to yield the inventive container having the various benefits discussed herein. Other collapsible containers may be adapted in accordance with the present invention. 
   The walls  18   a – 18   c  of the container  10  are configured for being selectively moved, hinged or pivoted between an erected position and a collapsed position. In the erected position, as shown in  FIG. 1 , the container  10  is suitable for containing product for shipment (not shown). In the collapsed position, as shown in  FIG. 3D , the size of the container  10  is reduced so that the container  10  may be return shipped in a more cost effective manner. To that end, the walls  18   a – 18   c  in the illustrated embodiment are hinged so that the walls  18   a – 18   c  may be moved from a locked, erected position to an unlocked, collapsed position. 
   Therefore, each wall structure  22   a – 22   c  essentially has a movable top or upper portion  18   a – 18   c , respectively, and a stationary bottom or lower portion  16   a – 16   c , respectively. The top portion  18   a – 18   c  is hinged inwardly (see  FIG. 3D ) with respect to the lower portion  16   a – 16   c  to generally reduce the size of the container  10  by half when the container  10  is in the collapsed position. The bottom portions  16   a – 16   c  of each wall structure  22   a – 22   c  remain in a vertically upright position, even when the container  10  is in a collapsed position (see  FIG. 3D ). 
   Container  10  further comprises a front wall structure  22   d  which comprises a frame  28  in combination with the bottom portion  14  of the base  12 . The frame  28  and bottom portion  14  of the base  12  define an open side  23  which allows side access to product in the dunnage structure or dunnage  24 . Front wall structure  22   d , like wall structures  22   a – 22   c  has a movable or hinged top or upper portion and a stationary bottom or lower portion as will be described below, in the illustrated embodiment. For purposes of the present document, any of the structures  22   a–d  may be considered a side structure. 
   As best illustrated in  FIG. 1 , container  10  further comprises collapsible dunnage  24  in the form of pouches  26 . Each of the pouches  26  is configured to contain at least one product (not shown) such as an automobile door, for example. However, the dunnage may assume other configurations, such as intersecting partitions, if desired. 
   Referring to  FIG. 1 , the dunnage  24  is accessible through the frame  28  of the container  10 . This type of container is known in the industry as a horizontal dispensing container. The dunnage  24  is operably coupled to and extends between the frame  28  and rear wall  18   b , from front to back. Preferably, for efficient use of space within container  10 , the dunnage  24  is also wide enough to fill the space between the opposing side wall structures  22   a  and  22   c . That is, the dunnage  24  will preferably use as much available space in the container  10  as possible so that a maximum amount of product (not shown) may be shipped in the container  10 . 
   In the erected position, the dunnage  24  receives and contains product for shipment. The dunnage  24 , as shown in  FIG. 2 , is collapsible and stays within the body  20  of the container  10  when the walls  18   a – 18   c  and a portion of the frame  28  are collapsed. In that way, the dunnage  24  remains with the container  10  when the empty container is returned to be refilled. See  FIG. 3D . When the container  10  is again erected by moving the walls  18   a – 18   c  and an upper portion of the frame  28  to an erected position and locking them in such a position, the dunnage  24  is erected and may again be utilized for shipping and containing product, as discussed further hereinbelow. Further discussion of collapsible dunnage is set forth in U.S. Pat. Nos. 5,725,119; 6,062,410; 6,230,916 and 6,540,096, all fully incorporated by reference herein. 
   As best illustrated in  FIG. 2 , frame  28  includes a pair of side frame members  30  and a top frame member  32  extending between the side frame members  30 . Each of the side frame members  30  has a lower or bottom portion  31  and an upper or top portion  33 . The upper portion  33  is hingedly coupled to the lower portion  31  to be selectively pivoted between a collapsed position and erected position about a horizontal pivot axis  35  which is defined by a pin  37 . See  FIGS. 1 and 2 . The interaction between the upper and lower portions  33 ,  31  of the side frame members  30  define pivotal joints  36 . 
   In alternative embodiments, the upper portion  33  of each side frame member  30  may be hingedly attached to the respective side walls,  18   a ,  18   c  of the container  10 . In such an embodiment, the lower, stationary portions  31  of the side frame members would be missing. In such an embodiment, a frame section is attached to the lower wall portions  16   a  and  16   c  of the base  12 . While the drawings illustrate the use of a pair of pivotal or hinged joints  36 , in alternative embodiments, the frame  22  could have any number of pivot points and any number of upper or lower portions. Applicant does not intend to be limited to any one frame. 
   The frame  22  also includes an upper or top cross member  32  which connects the upper portions  33  of the side frame members  30 . The dunnage  24  may be secured to this cross member  32  or to a handle  38  which can be used to pull the frame  28  and the attached dunnage  24  from a collapsed position, as shown in  FIG. 2  to an erected position shown in  FIG. 1 . Although one type of handle is illustrated, the handle may assume any other configuration or form. 
   The frame  28  is preferably made of metal, such as aluminum, but may be made of any other suitable material. The bottom portions  31  of frame members  30  are preferably fastened to the adjacent side portions  16   a ,  16   c  of the base  12  by appropriate fasteners, such as rivets, but may be joined in any desirable fashion. The upper portions  33  of side frame members  30  are preferably welded to cross frame member  32  to create a collapsible upper portion of the frame  28 , but may be joined in any desirable fashion. 
   As best illustrated in  FIG. 2 , the container  10  further comprises a pair of dunnage erection biasers  40  operably connected to the side members  30  of the frame  28 . As shown in  FIGS. 1 and 2 , each dunnage erection biaser  40  is located at or within the pivot or hinge joint  36  of the frame  28 . However, in other embodiments, the dunnage erection biaser  32  could be located elsewhere. If desired, only one dunnage erection biaser  40  could be used. 
   In a preferred embodiment, each dunnage erection biaser  40  comprises a torsion spring. However, other elastic devices or materials such as rubber, or other types of springs, such as a leaf spring, could be used. As best illustrated in  FIG. 2 , each torsion spring or biaser  40  has a pair of legs  42 ,  44  protruding outwardly from a central coiled portion  46 . One of the legs  42  is secured to the upper portion  33  of one of the side frame members  30  while the other leg  44  of the torsion spring  40  is secured to the lower portion  31  of one of the side frame members  30 . The natural tendency or bias of the torsion spring  40  is to return the upper and lower portions  33 ,  31  of the side frame members  30  to their erected, aligned position shown in  FIG. 1 . Thus, the torsion springs  40  urge the upper portions  33  of the side frame members  30  along with the cross member  32  of the frame  28  upwardly from the collapsed position shown in  FIG. 2  to the erect position shown in  FIG. 1 . Therefore, when an operator pulls upwardly on the handle  38  to erect the frame  28  and associated dunnage  24 , the torsion springs  40  lessen the load the operator must lift and consequently make it easier to erect the collapsed portion  50  of the frame  28  and associated dunnage  24 . 
   Referring to  FIG. 2 , the frame  28  is shown hinged in a collapsed position. The portion of the dunnage  24  supported by cross member  32  of frame  28  also collapses when the frame  28  is collapsed. The cross member  32  may collapse completely to the bottom or base  12  of container  10 . Alternatively, a stop structure (not shown) may be position in the body to prevent the upper portions  33  of the side members  30  of the frame  28  from hinging or collapsing completely to the bottom of the container  10 . In that way, a certain amount of space is maintained for the collapsed dunnage  24 , which lies beneath the collapsed portion  50  of the frame  28 . Generally, upper portion  33  of the side frame members  30  will not collapse below pivot joints  36 . 
     FIGS. 3A–3D  illustrate the method of collapsing the container  10  and its associated dunnage  24 .  FIG. 3A  illustrates an erected container  10  with the frame  28  collapsed about horizontal pivot axis  35 . The walls  18   a – 18   c  remain erected. The next step after collapsing the upper portion  50  of the frame  28  is to collapse the rear wall  18   b  of the container  10  in the direction of arrow  52 . Rear wall  18   b  is coupled to another end of the dunnage structure  24 . Therefore, when rear wall  18   b  is collapsed, the dunnage structure  24  is located thereunder.  FIG. 3B  illustrates the partially collapsed container  10 . 
     FIG. 3C  illustrates the side walls  18   a ,  18   c  being collapsed inwardly as shown by arrows  54  to provide a completely collapsed structure, as shown in  FIG. 3D . The hinge lines or hinge structures of the first-collapsing rear wall  18   b  are generally located below the hinge lines or structures of the latter collapsing side walls  18   a ,  18   c , so that the side walls  18   a ,  18   c  overlie rear wall  18   b  and the upper, collapsed-portion  50  of the frame  28 . When the container  10  is collapsed, along with the dunnage  24 , as shown in  FIG. 3D , the empty container may be returned in a generally 2:1 volume ratio with respect to an erected, full container. In that way, shipping and storage costs are reduced. As may be appreciated, the figures only illustrate one embodiment of a container in accordance with the aspects of the invention. Other different types of containers might be made to include the inventive features of the present invention. 
   While the present invention has been illustrated by the description of the embodiments thereof, and while the embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details representative apparatus and method, and illustrative examples shown and described. Accordingly, departures may be made from such details without departure from the spirit or scope of applicant&#39;s general inventive concept.