Abstract:
A material shelving comprises a basic shelving unit with vertical frame supports inter-tied with lateral load beams. At the rear of each shelf, between each pair of vertical frame supports, a backing cable is strung between two offset brackets just above the lateral load beams. Any pallets and material on pallets placed on the load beams of the shelving will be stopped from being pushed through by the backing cable.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to material-handling systems, and more particularly to inexpensive safety systems that prevent pallets from pushing in too far on their shelves.  
         [0003]     2. Description of Related Art  
         [0004]     Shelves and racks are a convenient way to store items, and can maximize floor space when palleted material is stored many levels high. A typical warehouse retail store, e.g., The Home Depot, has material racks that are two, three, and four levels high. Heavy items, like backup store inventory on a pallet, are placed and fetched from high above by a forklift. These heavy items can weigh anywhere from ten to two hundred pounds.  
         [0005]     Heavy items placed 10-20 feet high above aisles in material racks and on shelves can present a significant and not-so-rare personal injury risk. Shaking, bumping, and poorly stacked items can come tumbling down and hurt people below, or at a minimum damage the product. In particular, when shelves are arranged back-to-back, pallets loaded from one side can push through and disturb pallets behind on the adjacent shelves.  
         [0006]     In jurisdictions like California, very rigid rules have been developed that require particular spacings and seismic tie-togethers of pallet shelving placed back-to-back. A six inch flue space between back-to-back shelves is typical. Such flue space is important to maintain so fire sprinkler systems can get down to the lower levels of material on the shelves. But if nothing is in place to prevent it, material placed on one shelf can push out material on the shelf to the rear. The flue space can also be closed up or blocked by material or pallets protruding too far into this space.  
         [0007]     Cost is a major concern in any commercial business and material handling setup. Struts or solid walls have conventionally been placed across the backs of shelves to prevent material pushing through, but the per-shelf cost of these solutions can be too high.  
       SUMMARY OF THE INVENTION  
       [0008]     Briefly, a material shelving embodiment of the present invention comprises a basic shelving unit with vertical frame supports inter-tied with lateral load beams. At the rear of each shelf, between each pair of vertical frame supports, a backing cable is strung between two offset brackets just above the lateral load beams. Any pallets and material on pallets placed on the load beams of the shelving will be stopped from being pushed through by the backing cable.  
         [0009]     An advantage of the present invention is that a shelving safety system is provided that prevents material from being pushed through the backside.  
         [0010]     Another advantage of the present invention is that a safety cable is provided that is easy to install.  
         [0011]     A further advantage of the present invention is that safety cable systems are provided that are inexpensive to install.  
         [0012]     The above and still further objects, features, and advantages of the present invention will become apparent upon consideration of the following detailed description of specific embodiments thereof, especially when taken in conjunction with the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]      FIG. 1  is a perspective view of a safety netting system installed on a material rack shelving unit using offset brackets;  
         [0014]      FIG. 2  is a perspective view of a pallet stop cable system embodiment of the present invention installed on a material rack shelving unit like that of  FIG. 1  and using offset brackets like those detailed in  FIGS. 4A-4D  and  5 A- 5 F;  
         [0015]      FIG. 3  is a plan view of several shelves arranged back-to-back and using the pallet stop cable system embodiment of the present invention like that of  FIG. 2 ;  
         [0016]      FIGS. 4A-4D  are, respectively, perspective, top, end, and side view diagrams of an offset bracket like that used in the systems of  FIGS. 1 and 2 ; and  
         [0017]      FIGS. 5A-5F  represent an assembled offset bracket system in which an offset bracket is attached to a vertical pallet rack extension. In  FIG. 5A , the offset bracket is attached at its minimum offset position, wherein the front part where the netting attaches is at the left. In  FIG. 5B , the offset bracket is at a next offset position. In  FIG. 5C , the offset bracket is attached at another more extreme offset position. In  FIG. 5C , the offset bracket is at its most extreme offset position. In  FIG. 5E , a perspective view diagrams the vertical pallet rack extension slipped over a front frame part of a pallet rack and is secured with bolts. In  FIG. 5F , the vertical pallet rack extension is shown being secured with an alternative arrangement of bolts to a plate bar. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0018]      FIG. 1  illustrates a pallet-rack safety-netting system, referred to herein by the reference numeral  100 . The pallet-rack safety-netting system  100  comprises a number of extension brackets  101 - 109  that are bolted to three respective pallet rack vertical frame sections  110 - 112 . A set of suspension cables  114 - 125  are strung taut between the offset brackets  101 - 109  and support safety nets at their perimeters. For example, a safety net  126  is suspended away from the pallet rack framing by vertical cables  117  and  122 , and horizontal cables  121  and  123 ; and a safety net  128  is suspended between vertical cables  120  and  124 , and horizontal cables  123  and  125 . The nets can be attached to the cables every few inches by nylon cable ties or metal snap-hooks.  
         [0019]     Embodiments of the present invention permit the safety nets to be positioned at a variety of clearances from the face of the pallet rack framing. Such clearance is needed when the pallets loaded on the pallet rack have oversized material on them. The netting itself is provided to protect people in the aisleways from heavy material that might fall off the pallets in the racks. The offset brackets can be attached to either vertical frame sections of the pallet rack or to extensions of the vertical frame sections.  
         [0020]      FIG. 2  illustrates a pallet stop cable system embodiment of the present invention, and is referred to herein by the general reference numeral  200 . The system  200  is based on a shelving unit like that of  FIG. 1 . The pallet stop cable system  200  includes a set of vertical frame posts  201 - 206  between which are strung lateral loading beams  208 - 219 . In  FIG. 2 , the lateral loading beams  208 - 219  are configured for three shelves each in two bays. In the front, as in  FIG. 1 , a safety netting is supported by front cable brackets  220 - 228 , and netting cables  230 - 241 .  
         [0021]     Embodiments of the present invention have a set of rear cable brackets  242 - 250 , that support rear-stop cables  252 - 257 . These prevent pallets and material from being pushed out the rear of system  200 . The rear cable brackets  242 - 250  and rear-stop cables  252 - 257  are strategically placed just above lateral support beams  209 ,  211 ,  213 ,  215 ,  217 , and  219 .  
         [0022]     In  FIG. 3 , looking at the top plan view of six shelving system placed back-to-back, a group  300  includes shelving systems  301 - 306 . Such are each similar to that of  FIG. 2 . A set of rear-stop cables  307 - 312  is shown respectively attached to the rears of each of shelving systems  301 - 306 .  
         [0023]      FIGS. 4A-4D  represent an offset bracket embodiment of the present invention, and is referred to herein by the general reference numeral  400 . The offset bracket  400  can be used for offset brackets  101 - 109 ,  FIG. 1 . The preferred construction is generally in the form of a U-channel open at one end, as can be seen in  FIG. 4B . The open end slips around the vertical frame sections  110 - 112 ,  FIG. 1 , and is just wide enough to accommodate the width of the frame section. For example, 3″ inside. A pair of bolts is used to secure each bracket on the pallet rack at particular heights above the floor.  
         [0024]     The offset bracket  400  comprises a first arm  402 , a second arm  404 , and an end-plate  408 . A typical height is 2″ and a typical length is 15⅝″. Such form a box-section at the closed end and is very rigid and stiff so that the bracket can well-support and anchor the set of suspension cables  114 - 125  strung taut between the offset brackets  101 - 109 ,  FIG. 1 . The box section is suggested in the drawings as being separate steel sheetmetal pieces that interlock with tabs. Alternatively, the section could be welded.  
         [0025]     Two horizontal suspension cables can be accommodated by a pair of right-side holes  410  and  411  and their counterparts on the left side of bracket  400 . One could anchor and run left to support a netting on the left, and the other cable could anchor at the bracket and run to the right.  
         [0026]     In the bracket  400  illustrated in  FIGS. 4A-4D , there are four pairs of bolt holes  412 - 419  provided on the left and right arms for mounting the bracket to the vertical frame parts of a pallet rack. Only the ones on the right arm  404  are called out in  FIGS. 4A-4D . Theses bolts holes  412 - 419  are horizontally spaced to provide a range of offset adjustments, e.g., 3″, 6″, 9″, and 12″. Other spacings are possible and will be dictated by the applications.  
         [0027]     Two vertical suspension cables can be accommodated by a pair of top-side holes  420  and  421  and their counterparts on the bottom side of bracket  400 . One could anchor and run up to support a netting above, and the other cable could anchor at the bracket and run down toward the floor.  
         [0028]     The pairs of holes  410  and  411  for the horizontal suspension cables are offset slightly differently from the pairs of holes  420  and  421  for the vertical suspension cables, e.g., so the cables do not interfere at their points of criss-cross inside the box end of bracket  400 .  
         [0029]      FIGS. 5A-5F  show an assembled offset bracket system  500  in which an offset bracket  502  is attached to a vertical pallet rack extension  504 . In  FIG. 5A , a pair of bolts  506  and  507  are used to attach the offset bracket  502  at its minimum offset position, e.g., 5″ offset. The front part where the netting attaches is at the left. In  FIG. 5B , bolts  506  and  507  attach the offset bracket  502  at a next offset position, e.g., 6″ offset. In  FIG. 5C , bolts  506  and  507  attach the offset bracket  502  at another more extreme offset position, e.g., 9″ offset. In  FIG. 5C , bolts  506  and  507  attach the offset bracket  502  at its most extreme offset position, e.g., 12″ offset. In  FIG. 5E , the vertical pallet rack extension  504  is shown slipping over a front frame part  508  of a pallet rack and is secured with bolts  510  and  511 . In  FIG. 5F , the vertical pallet rack extension  504  is shown being secured with an alternative arrangement of bolts  512  and  513  to a plate bar  514 .  
         [0030]     Although particular embodiments of the present invention have been described and illustrated, such is not intended to limit the invention. Modifications and changes will no doubt become apparent to those skilled in the art, and it is intended that the invention only be limited by the scope of the appended claims.