Plastic pallet having deck suspension system

Abstract

The top of a thermoplastic pallet for transporting goods is comprised of a frame which is mounted on columns extending upwardly from a base. A subframe is attached to brackets within the interior opening of the frame. The edges of corrugated metal deck is attached to the subframe and spaced apart inwardly from the inner edge of the frame. There are lengthwise spaces between the subframe and the bridge parts of the frame, which bridges span the fork opening spaces between the columns. When the bridges are horizontally impacted, they can deform elastically into the spaces without causing any damage to the deck. Preferably the bridges comprise lengthwise impact absorber zones for good compliance to horizontal impacts.

1 . A pallet comprising: 
 a plurality of spaced apart columns;    a rectangular frame, attached to the tops of the columns and having inner edges and outer edges, comprising a multiplicity of bridges which span the spaces between the columns;    a subframe, spaced apart from the inside edges of the frame;    means, adjacent the columns, for supporting the subframe; and,    a deck attached to the subframe;    wherein there are lengthwise spaces between the inside edge of each bridge and the adjacent subframe.    
     
     
         2 . The pallet of  claim 1  further comprising a rectangular base, wherein said columns extend upwardly from the periphery of the base.  
     
     
         3 . The pallet of  claim 1  wherein the means for supporting the subframe comprises a multiplicity of brackets attached to the inner edge of the frame; and wherein each pair of adjacent brackets bounds the ends of one of said lengthwise spaces.  
     
     
         4 . The pallet of  claim 1  wherein each space has a length which is at least 75 percent of the length of the adjacent bridge.  
     
     
         5 . The pallet of  claim 4  wherein each space has a length which is equal to the length of the associated bridge.  
     
     
         6 . The pallet of  claim 1  wherein each space has a length which is at least 75 percent of the length of the adjacent bridge, wherein each bridge further comprises at least one lengthwise impact absorber zone.  
     
     
         7 . The pallet of  claim 6  wherein the pallet is composed predominately of thermoplastic; and, wherein each bridge further comprises a metal stay running along the length of at least one bridge in proximity to the outer edge thereof.  
     
     
         8 . The pallet of  claim 1 , further comprising: vertical ribs, running transversely within at least one space, the ribs shaped for low resistance to bending, to enable the bridge associated with the space to deform inwardly under a horizontal impact load.  
     
     
         9 . The pallet of  claim 1  wherein a multiplicity of said spaces are each at least one inch wide and 5 inches long, and sufficient in shape to enable manual grasping of the pallet.  
     
     
         10 . The pallet of  claim 1  wherein the frame is comprised of thermoplastic and the deck is a textured metal sheet.  
     
     
         11 . The pallet of  claim 10  wherein the deck has a circumscribing flange where the deck is attached to the subframe.  
     
     
         12 . The pallet of  claim 1  wherein the deck is predominately thermoplastic.  
     
     
         13 . The pallet of  claim 1  wherein the outer edges of the subframe and of the deck are at least about 4 inches from the outside edge of the frame.  
     
     
         14 . The pallet of  claim 1  wherein the edge of the deck extends outwardly from the subframe over said spaces.  
     
     
         15 . The pallet of  claim 1  wherein the base is comprised of one or more cross rails which run across the center of the base; wherein the pallet further comprises a center column at the center of the base; and, wherein the deck is attached to the top of the center column.  
     
     
         16 . The pallet of  claim 3  wherein the subframe is an integral part of the deck.  
     
     
         17 . A rectangular pallet comprising: 
 a base comprised of outer rails interconnected to form a rectangle;    eight spaced apart outer columns extending upwardly from the outer rails and one center column extending upwardly from the center of the base;    a rectangular frame, attached to the tops of the outer columns, the frame having inner edges and outer edges and comprised of a multiplicity of bridges which span the spaces between the columns;    a subframe, spaced apart from the inside edge of the frame;    means for supporting the subframe; and,    a deck attached to the subframe, the edges of the deck spaced apart from the inner edges of the frame; wherein the deck and frame comprise the top of the pallet.    
     
     
         18 . The pallet of  claim 16  wherein the means for supporting the subframe comprises a plurality of brackets, one each extending inwardly from the frame at the location of each outer column; and wherein each pair of adjacent brackets bounds the ends of a space running lengthwise between each bridge and adjacent portion of subframe.  
     
     
         19 . The pallet of  claim 17  wherein each base rail comprises a metal beam.  
     
     
         20 . The pallet of  claim 17  wherein the each bridge comprises an impact absorber, and wherein the portions of the frame which overlie the columns are free of impact absorber.  
     
     
         21 . The pallet of  20  further comprising: metal stays proximate the outside edges of each bridge; wherein the stay is closer to the outer edge than is the impact absorber.  
     
     
         22 . The pallet of  claim 18  wherein the deck is fastened to the subframe only at points between the columns and at the corner column brackets.  
     
     
         23 . In a rectangular predominately plastic pallet for use with a forklift device, of the type having a top comprising a deck, where the top is mounted on spaced apart columns which extend upwardly from a pallet base, the improvement which comprises: a top comprised of a rectangular frame which forms the periphery of the top; the frame comprised of bridges which span spaces between the columns; and a deck having edges which are spaced apart from the inner edge of the frame along at least 75 percent of the length of each bridge.  
     
     
         24 . The pallet of  claim 23  wherein the deck is connected to the frame by means of brackets located in vicinity of the columns; and wherein the bridges comprise length wise impact absorbers.  
     
     
         25 . The pallet of  claim 23  wherein the total of the lengths of all spaces is greater than 50 percent of the length of the inner edge of the frame.