Collapsible drum

Abstract

The present invention is directed to a collapsible drum for transporting materials. The present invention solves problems associated with reusing and efficiently transporting shipping containers designed for retaining bulk materials, including hazardous substances, and insuring reliable structural integrity with every use. The collapsible drum of the present invention is adapted for integration with standard handling equipment, and has a permanently secured, collapsible drum floor and fluted sidewalls that enable an operator to collapse and roll the empty drum into a compact tube.

1 ) A collapsible drum for handling materials, the collapsible drum comprising:
 a) a plurality of vertical ribs for supporting the wall of the drum in an erected state, the plurality of vertical ribs being connected or disconnected along the circumferential plane of the drum;   b) a flexible skin covering the external surfaces of the vertical ribs;   c) a flexible drum floor permanently secured to the flexible skin covering the external surfaces of the ribs; and   d) one or more lifting features secured to a pair of diametrically opposed vertical ribs thereby facilitating lifting of a loaded or partially loaded drum by drum handling equipment.   
     
     
         2 ) The collapsible drum of  claim 1  wherein the pair of diametrically opposed vertical ribs having one or more lifting features thereon have higher shear strength than the remainder of the plurality of vertical ribs. 
     
     
         3 ) The collapsible drum of  claim 1  wherein at least a subset of the vertical ribs is connected along the circumferential plane of the drum and this subset of ribs is produced from rigid fiberboard scored to form the ribs. 
     
     
         4 ) The collapsible container of  claim 3  wherein the rigid fiberboard is scored evenly from both sides and to the same depth on both sides so that the compressed portion of the fiberboard is centered between the inner and outer surfaces of vertical ribs. 
     
     
         5 ) The collapsible container of  claim 1  wherein at least a subset of the vertical ribs is connected along the circumferential plane of the drum and this subset of ribs is produced by extrusion. 
     
     
         6 ) The collapsible container of  claim 1  wherein at least a subset of the vertical ribs is connected along the circumferential plane of the drum and this subset of ribs is produced by pressing a deformable rigid material. 
     
     
         7 ) The collapsible container of  claim 1 , further comprising an inner lamination layer disposed on the internal surfaces of the plurality of vertical ribs and overlapping the top edges and bottom edges of the plurality of vertical ribs to adhere to the external surfaces of the plurality of vertical ribs. 
     
     
         8 ) The collapsible container of  claim 7  wherein the flexible skin covering the external surfaces of the vertical ribs overlaps the top edges of the plurality of vertical ribs to securely adhere to the inner lamination layer and extends beyond the bottom edges of the plurality of vertical panels to create a free-hanging bottom margin. 
     
     
         9 ) The collapsible container of  claim 8  wherein the free-hanging bottom margin of the flexible skin covering the external surfaces of the vertical ribs folds inward along the radius of the drum to lie parallel to the flexible drum floor during mating. 
     
     
         10 ) The collapsible container of  claim 9  wherein the flexible drum floor is permanently attached to the bottom margin by stitching the two layers together in a continuous circumferential loop in the plane of the flexible drum floor. 
     
     
         11 ) The collapsible container of  claim 9  wherein the flexible drum floor is permanently attached to the bottom margin by welding the two layers together in a continuous circumferential loop in the plane of the flexible drum floor. 
     
     
         12 ) The collapsible container of  claim 9  wherein the flexible drum floor further comprises at least two parallel layers and wherein the bottom margin of the flexible skin covering the external surfaces of the vertical ribs is sandwiched between the two parallel layers prior to mating. 
     
     
         13 ) The collapsible container of  claim 1  wherein the flexible drum floor is made of the same material as the flexible skin covering the external surfaces of the vertical ribs. 
     
     
         14 ) The collapsible container of  claim 1  wherein the flexible drum floor is manufactured from a non-rigid woven material with a low modulus of elasticity. 
     
     
         15 ) The collapsible container of  claim 1  wherein the flexible drum floor is manufactured from a material chosen from the group consisting of woven polyurethane, reinforced polyethylene, woven fiberglass, and polymeric material. 
     
     
         16 ) The collapsible container of  claim 1  wherein the inner lamination layer is manufactured from a material chosen from the group consisting of woven polyurethane, reinforced polyethylene, woven fiberglass, and polymeric material 
     
     
         17 ) The collapsible container of  claim 1  wherein the flexible skin covering the external surfaces of the vertical ribs is manufactured from a material chosen from the group consisting of woven polyurethane, reinforced polyethylene, woven fiberglass and polymeric material. 
     
     
         18 ) The collapsible container of  claim 1  wherein the a plurality of vertical ribs are made from a material chosen from the group consisting of fiberboard, cardboard, high density polyethylene, wood, metal, composite and polymeric material 
     
     
         19 ) The collapsible container of  claim 1 , further comprising a retaining element secured to the inner surface of the flexible drum floor for retaining a disposable liner disposed within the containment cavity. 
     
     
         20 ) The collapsible container of  claim 19  wherein the retaining element is Velcro® and a mating Velcro® portion is attached to an outer surface of the disposable liner.