Patent Publication Number: US-2011049074-A1

Title: Retainer

Description:
FIELD OF THE INVENTION 
     This invention generally relates to a retainer for pallet racks and the like. In particular, this invention relates to a retainer that is easily and quickly attached to the pallet rack and which is used as a safety barrier to prevent pallets from being pushed off the pallet rack and to assist in locating pallets on the rack at the correct depth. 
     BACKGROUND OF THE INVENTION 
     Pallet racks provide a vital storage support structure in large warehousing, storage and distribution facilities. In such facilities, forklifts or other vehicles are commonly employed to load or remove pallets from the pallet racks. Large retailing operations have also recently employed pallet racks to both store and display products in the retail showrooms. As the size of the facilities and the direct access of the public to pallet racks systems have increased, the potential for damage and/or injury due to accidental dropping or improper loading of the pallet racks has also increased. 
     Various safety systems have been contemplated and used to enhance the safety and minimize safety risks from mishandling or misloading of pallet racks, for example, retractable safety net systems which are mounted on pallet racks to prevent accidental dropping. Other forms of apparatus for selectively holding, retaining, supporting, and/or securing objects upon one or more shelves, and prevent such objects from inadvertently falling have also been used. Certain types of apparatus employ a retractable, flexible, elastic barrier, which permits observation and inspection of objects contained within an interior compartment or enclosure on the shelf. The barrier can be stretched and pulled aside to allow access to the compartment or enclosure, which when released, retracts back to an original position to function as a barrier that retains objects within the compartment or enclosure to prevent the inadvertent escape of such objects contained therein. Further systems involve the use of mesh or horizontal bars attached to the rear of the pallet rack to prevent pallets being pushed out through the back of the pallet rack. However, it is possible for a pallet to inadvertently be placed on top of a horizontal bar and therefore be incorrectly stored and also thereby reduce available space for additional pallets to be stored. In yet a further attempt to provide a system for preventing pallets from falling from racks, a system of lateral load beams and brackets has been used. The additional load beams and associated brackets is a complex system that requires significant disruption to warehouse operation, if it is to be retro-fitted to an existing pallet rack structure. 
     Unfortunately, all of the above-mentioned safety systems have drawbacks, from cost to complexity. The present invention seeks to address the problems and drawbacks of previous retainer systems by providing a simple yet effective solution to effectively retain pallets in racks. 
     SUMMARY OF THE INVENTION 
     The present invention provides a pallet retainer comprising at least a plurality of spacer members and at least one upright member, wherein each spacer member includes an opening through which the upright member passes and wherein the spacer member positions the vertical member to prevent a pallet being placed to deeply within a bay. 
     In certain embodiments of the present invention at least one of the spacer members is engageable with a rear load beam of a pallet rack. In some embodiments of the present invention at least one of the spacer members is substantially fixed to a rear load beam of a pallet rack. Preferably, the upright member is positioned in a substantially vertical orientation behind the pallet rack. 
     In certain embodiments of the present invention, the spacer member is constructed of steel or plastic. In some embodiments of the present invention, the upright member is constructed of steel. 
     The present invention also provides a pallet rack comprising a pallet retainer according to the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG. 1  shows the basic structure of a standard pallet rack. 
         FIG. 2  shows typical arrangements of pallet racks in a warehouse, against a wall (A) or in a double entry arrangement (B). 
         FIG. 3  shows detail of the rear of a pallet and its interaction with the rear load beam. 
         FIG. 4  shows an exemplary embodiment of the present invention, in perspective view as attached to the rear load beam (sketch, A), and plan view (B) and side view (C) of a spacer member. Panel D shows a typical installation of this embodiment of the present invention, from the rear of the pallet rack. 
         FIG. 5  shows three alternative embodiments of a spacer member of the present invention (A, B and C, D, E and F, G), in plan view (A, C and G), side view (B, D and F), and end-on (E). 
         FIG. 6  shows further alternative spacer members suitable for use in embodiments of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention relates broadly to a retainer for pallet racks as used, for example, in warehouses. 
     Referring to all the drawings wherein like reference numerals designate like or corresponding parts throughout the several views, the following description refers to the specific, illustrated embodiments of the present invention and is in no way intended to limit the scope of the present invention to the specific, illustrated embodiments. 
     As illustrated in  FIG. 1 , a typical pallet rack generally has three main components: posts  10 , connectors  20  and load beams  30 , 31 ; wherein two adjacent posts  10  are generally joined by a plurality of horizontal and diagonal braces  15  to form a frame end  40 . Two frame ends  40  may be joined by load beams  30 , 31  to form a frame. A bay is the area into which pallets are placed and are defined by load beams  30 , 31  (upon which the pallet is placed) and two frame ends  40 . In normal use, a pallet rests on a rear load beam  30  and a front load beam  31 . Another important feature of a pallet rack is the connector  20  between the load beams  30 , 31  and the posts  10  to which they are attached. The weight of a load placed on the beams  30 , 31  is transferred through the connector  20  to the posts  10 . The posts  10  thus ultimately carry the total weight within the rack. 
     Pallet racks are generally free standing but with structures positioned behind them. Such structures include walls or fencing  60  ( FIG. 2A ) or other pallet racks ( FIG. 2B ). Arrows in  FIG. 2  illustrate the direction of entry of pallets into racks arranged in such manners. Pallets are placed in bays by a forklift driver, generally from an obscured position, often resulting in the pallet being placed too deeply within the bay or with incorrect alignment such that the pallet does not sit properly or securely upon the load beams. Such situations may result in damage to the product, stock, neighbouring pallets, walls or fencing in the vicinity of the pallet. 
     As illustrated in  FIG. 3 , the pallet  85  often includes a portion  80  for interacting with, usually, the rear load beam  30  to securely locate the pallet in the bay. 
     The present invention provides a pallet retainer comprising at least a plurality of spacer members and an upright member, wherein each spacer member includes an opening through which the upright member passes and wherein the spacer member positions the vertical member to prevent a pallet being placed to deeply within a bay. In certain forms of the invention each of the spacer members is engagable with a rear load beam of a pallet rack to position the upright member a predetermined distance behind the pallet rack. 
       FIG. 4  illustrates an embodiment of a pallet retainer according to the present invention; wherein the pallet retainer comprises a spacer member  100  and an upright member  110 , wherein the spacer member  100  includes an opening  105  through which the upright member  110  passes. In the illustrated embodiment, the spacer member  100  includes an engagement portion  108  which is adapted to engage with a rear load beam  30  of a pallet rack.  FIG. 4A  shows an “in use” arrangement of this embodiment of the invention, wherein the engagement portion  108  engages with the rear load beam  30  of a pallet rack. The engagement portion  108  may be of any suitable shape to permit engagement of the spacer member  100  with the rear load beam  30 , such that, in use, if force is applied to the upright member  110  by a pallet being pushed up against it, that force is distributed to the rear load beam  30  via the spacer member  100  to which it is attached. In use, a plurality of spacer members  100  would be used, in particular, there would be at least one additional spacer member  100  positioned on a rear load beam  30  above and/or below the rear load beam illustrated in  FIG. 4A . This arrangement allows the upright member  110  to be positioned firmly so that there would be minimal movement of the upright member  110  when a pallet is pushed against it. Exemplary arrangements of engagement portions  108  are illustrated in  FIGS. 4 ,  5  and  6 . However, alternative arrangements are envisaged, for example as illustrated in  FIG. 6C  and discussed further below, the spacer member  100  could include means by which it could be fixed directly to the rear load beam  30  by any method known in the art, including but not limited to: bolting, screwing and/or welding. 
     The purpose of the spacer member  100  is to space the upright member  110  away from the rear of the pallet rack. The spacer member  100  includes an opening  105  through which the upright member  110  passes. The position of the opening  105  is such that when a pallet is in a bay, but not pushed too far into the bay, the upright member  110  does not contact the pallet.  FIG. 4  shows illustrations of an exemplary spacer member  100  and the distance marked “a” provides a gap between the rear of the rear load beam  30  and the upright member  110  such that the pallet can be correctly positioned within the bay without contacting the upright member  110 . In certain embodiments of the present invention the dimension “a” will be in the order of 10 to 100 mm greater than the overhang  80  of the pallet  85 . In specific embodiments, the dimension “a” will be in the order of 10 to 50 mm, or 10 to 25 mm, or 13 mm greater than the overhang  80  of the pallet  85 . If the pallet  85  is placed too far into the bay, it will contact the upright member  110  instead of damaging other product, stock, neighbouring pallets, walls or fencing located behind the pallet rack. 
     Referring to the embodiment of the engagement portion  108  as illustrated in the various Figures, dimension “b” will be approximately the height of the rear load beam  30 . In typical pallet racks the dimension “b” will be in the range of about 50 to 150 mm. Dimension “c” will be approximately the width of the rear load beam  30 . In typical pallet racks, the dimension “c” will be in the range of about 30 to 60 mm. Dimensions “b” and “c” are chosen to provide a close fit of region  108  to the rear load beam  30 , so that the spacer member  100  will not readily fall off the rear load beam. The dimension “d” may be any suitable size, such as, but not limited to: 50 to 300 mm, or 50 to 200 mm, or 70 to 150 mm, or 80 to 120 mm. 
     As illustrated in  FIG. 2B , rows of pallet racks may be placed back-to-back (double entry rack) such that when a pallet is put into a bay from a first side, it may come into contact with a pallet in the bay located therebehind. This can result in pallets resting on or against each other which could have detrimental effects, such as reducing the number of pallets that can be stored, making pallets difficult to access and/or remove, or damaging the pallets and/or their contents. In a typical arrangement, the distance between racks in a double entry rack arrangement is approximately 380 mm. In such situations, it is desirable to have a pallet retainer according to the present invention located between the adjacent pallet racks. This may be achieved by having a spacer member that spans the distance between the rear load beams of adjacent pallet racks. Illustrated in  FIGS. 5A to 5E  are embodiments of spacer members that may be used in such a situation. The dimension “e” will typically be the distance between the racks plus twice the width of the rear load beams, so that a close fit is achieved. The opening  105  in such spacer members would typically be substantially centrally located across the width of the spacer member as illustrated. The embodiment illustrated in  FIGS. 5C to 5E  also includes a rib portion  109  to add strength to the section of spacer member  100  that spans the gap between adjacent pallet racks. 
     In circumstances where double entry racks are not a standard distance apart, it may be desirable to have individual spacer members (see  FIGS. 5F  and G) that overlap such that an upright member may pass through aligned openings. In order to allow for some degree of overlap between the spacer members, the opening  105  may be slightly elongated, such as illustrated in  FIG. 5G . 
     It is envisaged that the spacer members  100  will be constructed of a strong material able to withstand the considerable forces that may be applied when a heavy pallet is pushed hard against the upright member  110 , such as, but not limited to: steel, aluminium or plastic. Preferably, the spacer member is constructed of steel. 
     The upright member  110  passes through the opening  105  in the spacer member  100 . The upright member  110  may be any sufficiently strong elongate member, such as, but not limited to a pipe. In such embodiments, the upright member  110  may have a substantially circular cross-section. The opening  105  in the spacer member  100  should provide a close fit to the upright member  110  in order to provide efficient transfer of force to the rear load beam  30 , as discussed above. Also encompassed by the present invention are upright members  110  being non-circular in cross-section, for example, being of substantially square cross-section. In certain embodiments of the present invention, the upright member  110  is a pipe having a circular cross-section of 25 to 100 mm, or 30 to 75 mm, or of approximately 50 mm in diameter. The length of the upright member  110  will depend upon the specific application. It will need to be approximately as high as the pallet rack if all bays are to be protected. Installation of such upright member  110  may be difficult, therefore it is envisaged that in certain circumstances it is desirable for the upright member  110  to be comprised of more than one length of material. When more than one length of material is used, they may be joined by a joining piece that substantially maintains the strength of the upright member  110 . The skilled addressee would realise that it is most preferred to keep the upright member  110  as a single piece of material; however, if it is to be composed of multiple pieces, then it should be kept to as few separate pieces as possible to maintain its strength and to potentially reduce manufacturing costs. 
     In order to accommodate the upright member  110 , the opening  105  may be of similar shape to the cross-section of the upright member  110 . In the illustrated embodiments, the opening  105  is substantially circular. The opening  105  may be slightly larger than the cross-section of the upright member  110 , for example approximately 2 to 5 mm larger in diameter in the case of a circular opening. The slightly larger size may facilitate assembly of the pallet retainer. 
     As illustrated in  FIGS. 1 and 2 , pallet racks  1  are usually arranged such that pallet bays are arranged one on top of the other, in for example, “columns”. Therefore, it is envisaged that a pallet retainer according to the present invention will also be arranged substantially vertically. In particular, the upright member  110  will generally be positioned in a substantially vertical orientation to provide a barrier behind the pallet rack  1  to prevent a pallet being pushed too far into a bay. Furthermore, in certain embodiments of the present invention, there may be more than one pallet retainer for each column of pallet bays. While the lower end of the upright member  110  may rest against the floor, it may also be held in a substantially fixed location by the use of standard hardware, such as, but not limited to, a fencing flange and appropriate floor fixings. Alternatively, a floor flange  120  may be employed, wherein the floor flange  120  is similar to a fencing flange but having a higher return portion to more securely accommodate the upright member  110 . 
     The embodiments of the present invention described herein are intended to provide an understanding of the invention but are not intended to limit it in any way. For example, it is within the scope of the present invention to use more than one retainer behind each pallet rack. In addition,  FIG. 6A  illustrates an alternative shape for the spacer member  100  that may find application in certain situations by providing a larger area of the rear load beam  30  over which any forces are to be distributed. The embodiment illustrated in  FIG. 6B  is similar to that illustrated in  FIG. 3 , except that a cut out region  107  is provided to facilitate assembly of the pallet retainer. In particular, the upright member  110  could be installed without the need to provide the upright member  110  in multiple pieces. The embodiment illustrated in  FIG. 6C  is similar to that illustrated in  FIG. 6B , except that the spacer member  100  is intended to be permanently affixed to the rear load beam  30 , for example by welding. Such spacer members could readily be incorporated into the rear load beam  30  during manufacture of the rear load beam  30 . The illustrated embodiment also includes a cut out region  107  that would facilitate assembly of the pallet retainer in a similar manner to that described above. 
     In yet a further embodiment, the spacer member  100  may include a further opening to allow the spacer member  100  to be fixed to rear load beam  30 . Such additional openings may be provided in combination with, or as an alternative to, the rear load beam engaging region  108 . Suitable fasteners for such fixing include, but are not limited to, bolts, screws and rivets. 
     The present invention also provides a pallet rack comprising a pallet retainer according to the present invention. In certain embodiments, the retainer may be retro-fitted to an existing pallet rack. In other embodiments, the spacer members  100  may be supplied already attached to rear load beams  30  for use in the assembly of a pallet rack. Once such a pallet rack has been assembled, an upright member  110  may be added to complete the pallet rack comprising a pallet retainer. As discussed above, in certain embodiments of the present invention, more than one pallet retainer may be used per bay of a pallet rack. For example, two or more pallet retainers may be used per bay. 
     The upright member of the pallet retainer of the present invention may also provide a mounting for various additional components, such as, but not limited to: (i) a barrier in order to create a dividing wall or a secure area; (ii) netting or mesh to form a barrier to prevent stock from falling from the rear of a pallet; and (iii) fire sprinkler services. 
     Where the terms “comprise”, “comprises”, “comprised” or “comprising” are used in this specification, they are to be interpreted as specifying the presence of the stated features, integers, steps or components referred to, but not to preclude the presence or addition of one or more other feature, integer, step, component or group thereof. 
     Further, any prior art reference or statement provided in the specification is not to be taken as an admission that such art constitutes, or is to be understood as constituting, part of the common general knowledge.