REINFORCED CONTAINER AND METHOD OF MAKING THE SAME

Abstract: A reinforced corrugated carton (10) is provided with an inside tubular rectangular liner (15) and a bottom pad (17) fitted down inside the liner and adhesively secured to the inside bottom flaps of the carton. Disposed entirely peripherally around the carton sidewalls (12) and extending upward for a distance from substantially the bottom thereof on the outside is a belt (19) of non-­ woven backing material (20) with yarns (illustrated dia­ grammatically at 22) laminated thereon and extending peripherally laterally completely therearound. The yarns may be of any material which exhibits minimal elongation under tension, and the belt backing material may typically be of non-woven polyester. The yarns may be closely spaced at the bottom edge of the belt, with the spacing between the yarns increasing towards the top of the belt. The belt (19) is wrapped around the carton (10) with the backing material (20) thereagainst and held thereto with several glue spots with the ends of the belt brought into abutment on the surface of the carton. A patch (24) of the same material as the belt is then glued firmly over the butt joint with the yarns of the patch facing and adhered to the yarns of the belt.

Description: This invention relates generally to corrugated containers, and more particularly relates to such con­ tainers for holding flowable granulated materials and flowable gelatinous substances. The granulated materials flow almost like fluids, and the gelatinous substances have substantial rates of cold flow, some of these mater­ ials being of relatively high density. Containers for such products are usually made in sizes of several feet on each dimension, and when holding materials of the nature described can weigh hundreds of pounds. Typically, such containers may be made from 600 lb. test double wall corrugated material or 1100 lb. test triple wall corrugated material. Even such heavy duty containers when filled with the flowable materials and stacked two to four containers high for shipment are not immune from bulging of the container walls in the bottom units, with the attendant potential of container rupture or column failure which causes the upper boxes to topple over. Consequently, it has been necessary in the past to either compartmentalize such containers as load distributing structures, or to enclose such containers in wooden frames to provide wall support therefor. The novel containers embodying the invention are capable not only of eliminating the necessity for using wooden frames or compartmentalizing the containers, but also of permitting reduction in the necessary strength of the container wall structures from the previously mentioned types to container walls made of approximately 350 lb. test double wall corrugated material. These changes effect a substantial cost reduction in the con­ tainers used for these applications. It is a primary object of the invention to provide a novel reinforced corrugated container capable of safely holding flowable granulated materials and flowable gelat­ inous substances of relatively high density utilizing thinner than normal container walls and eliminating compartmentalization within the carton or wooden external structural framing as supplementary carton support struc­ tures. Another object of the invention is to provide a novel reinforced container as aforesaid in which the corrugated carton, or an interior tubular liner, is pro­ vided with a retaining belt extending entirely peripher­ ally thereabout and upward for a distance from the bottom of the carton or liner. Yet another object of the invention is to provide a novel reinforced container as aforesaid wherein the reinforcing belt structure is made of a non-woven backing material with parallel disposed yarns laminated thereon and extending lengthwise of the belt structure, the belt being secured to the carton, or interior tubular liner, to thereby dimensionally stabilize the carton. Thus, from one aspect, the invention provides a high strength reinforced container comprising a corrugated carton structure including means forming sidewalls, a top closure and a bottom closure, characterised by a wide reinforcing belt having a pair of side edges and a pair of opposite ends, said belt being disposed effectively entirely peripherally around the sidewalls and secured thereto, said belt extendind upward for a distance from substantially the bottom of said carton structure, and securing means securing the said opposite ends of said belt against relatively movement in belt loosening directions, said belt comprising a non-woven backing material to which is adhered a parallel array of yards extending lengthwise of said belt, siad yarns being of a type which exhibits minimal elongation under tension, and wherein said securing means comprises a patch made of the same material as said belt, said patch having upper and lower side edges and being adhesively secured to said belt with the yarns of the patch and belt being disposed in facing relation and sandwiched between the backing material of said belt and patch. A further object of the invention is to provide a method of making the aforedescribed reinforced con­ tainers. Thus from another aspect, the invention provides a method of reinforcing a container against rupture and excessive deformation by utilization of a lengthwise substantially inextensible wide fabric belt having a pair of laterally spaced apart side edges and a pair of opposite ends and being of a type comprising a non-woven backing material to one surface of which is adhered a parallel array of yarns extending lengthwise of said belt, said yarns being of a type whcih exhibits minimal elongation under tension, being spaced closely together in parallel array at one edge of the belt, being relatively widely spaced at the other edge of the belt, and being continuously graded in spacing density between the two edges of the belt, said container being of the types compris­ ing a corrugated carton structure including means forming sidewalls, a top closure and a bottom closure, the method being characterised by the steps of, a) disposing said fabric belt lengthwise effectively completely peripherally around the sidewalls with the edge with closely spaced yarns positioned substantially at the bottom of the sidewalls and the edge with the widely spaced yarns positioned upward thereform, and with the backing material disposed flatwise against the surface of the sidewalls, b) adhesively securing the belt backing material to the sidewalls in the position aforesaid, and c) securing the opposite ends of the belt against relative movement in belt loosening directions by adhesively securing to the belt a patch made of the same material as the belt with the yarns of the patch and belt being disposed in parallel facing relation and sandwiched between the backing material of said belt and patch. Briefly, as will be subsequently described in con­ nection with the drawings appended hereto, the corru­ gated cartons embodying the invention may be of the order of 35 to 50 inches in height and somewhat greater in length and width, and are provided with an inside tubular rectangular liner and a two ply bottom pad fitted down inside the liner and adhesively secured to the inside bottom flaps of the carton. In one embodiment of the invention there is disposed entirely peripherally around the outside of the carton sidewalls and extending upward for a distance from substantially the bottom thereof a belt of non-woven backing material with yarns laminated thereon and extending peripherally laterally completely around the carton. The belt yarns may be of any material which exhibits minimal elongation under tension. In another embodiment of the invention the belt is disposed around the tubular liner which as a unit fits within the carton. The belt backing material may typically be of non-woven polyester and approximately 20" or so in width extending upward from substantially the bottom of the carton or liner, and the yarns may typically each be 1800 denier formed of approxiamtely 250 fiberglass fila­ ments and arranged with a side by side density of 20 to the inch at the bottom reducing to 5 to the inch at the top and graded in between. The belt is wrapped around the carton or liner with the backing material against the carton or liner and held thereto with several glue spots, with the ends of the belt brought in to abut­ ment on the surface of the carton. A patch of the same material is then glued firmly over the butt joint with the filaments of the patch facing and adhered to the filaments of the belt. Various embodiments of the invention will now be described with reference to the accompanying drawings wherein: Figure 1 is an isometric view of a reinforced container according to the invention with the top flaps open and with a portion of a lower corner structure being sectioned away to disclose underlying details; Figure 2 is an enlarged fragmentary section taken through the carton of Figure 1 as would be seen along the line 2-2 on Figure 1; Figure 3 is a horizontal sectional view through the novel carton according to the invention as would be seen when viewed along the line 3-3 on Figure 2, and also disclosing a partially removed section of the bottom structure to disclose the underlying configuration; Figure 4 is a fragmentary enlarged section through the wall of the reinforced container according to the invention as would be seen when viewed along the line 4-4 on Figure 3; Figure 5 is an enlarged fragmentary corner detail of an alternate way of applying the locking patch to the reinforcing belt at the corner instead of on the face of a carton panel; Figure 6 is an isometric exploded view of another form of reinforced container according to the invention in which the container liner is reinforced instead of the outer carton; Figure 7 is an enlarged fragmentary view through the container structure of Figure 6 as would be seen when viewed along lines 7-7 on Figure 6; and Figure 8 is a fragmentary enlarged section through the container wall as would be seen when viewed along lines 8-8 on Figure 7. In the several figures, like elements are denoted by like reference characters. Referring now to the drawings and first to Fi­ gures 1 to 4, there is seen a carton referred to generally as 10 having the usual top flaps 11, sidewalls 12, in­ terior bottom flaps 13 and exterior bottom flaps 14, the carton being formed in the normal and usual structural fashion for such corrugated cartons. Disposed vertically within the carton is a rectangular liner tube 15 having its ends lapped at one corner by the flap 16. Disposed within the confines of the liner tube 15 and placed flat­ wise downward upon the interior bottom flaps 13 is a bottom pad 17 adhered to the upper surfaces of the inte­ rior bottom flaps 13 by adhesive 18. Wrapped peripherally about the walls of the carton 10 for a distance extending upward from the bottom edge of the carton is a reinforcing belt 19 made of a non-woven backing material 20 which typically could be polyester, to which is adhered a plurality of side by side yarns 21 extending longitudinally of the length of the reinforcing belt and spaced laterally in a varying density arrangement as shown by the lines 22, the yarns being closely spaced at the bottom edge of the belt and gradually becoming wider in spacing towards the top of the belt. The yarns and their spacings typically could be 1800 denier yarns formed of 250 fiberglass filaments each at a density of 20 to the inch at the bottom edge of the belt reducing to 5 to the inch at the upper edge of the belt and graded therebetween. As best seen in Figures 1 and 3, the ends of the reinforcing belt are abutted on one face of the carton as shown at 23, and a locking patch 24 is adhesive­ ly secured across the abutment line 23 to fixedly secure the ends of the reinforcing belt together and prevent their being separated under stress from the load within the carton. The patch 24 is shown with gradation lines in Figure 1, but it is to be understood that these grada­ tion lines represent yarns on the inner face of the patch and not on the outer face. This is more clearly shown in Figure 4 where the patch is shown to be of the same structure as the belt and includes a non-woven backing portion 25 and an array of yarns 26. As also shown in Figure 4, the yarns and backing of the patch 24 are ad­ hered to the yarns and backing of the reinforcing belt 19 by adhesive 27, with the yarns 21 and 26 facing one another. As shown in Figure 4, the yarns do not appear to be in contact with each other, and this could occur in the relatively widely spaced upper regions of the belt, but toward the lower regions of the belt where the density is much higher, the yarns 21 and 26 will e in close proximity or substantial engagement with one another at their points of adherence. An alternative locking patch configuration, and a preferred one, is shown in the detail of Figure 5 which differs only from the structure shown in the other figures in that the ends of the reinforcing belt 19 are abutted at a corner of the carton instead of on a face of the carton, and the patch 24 is applied around the corner of the carton, all as shown in Figure 5. Considering now Figures 6 to 8 there is seen a carton 10′ having sidewalls 12′ and a tubular liner 15′ as in Figures 1 through 5, but wherein the reinforcing belt 19′ with its locking patch 24′ is disposed about and adhesively tacked to the periphery of the liner 15′ instead of about the outer lower periphery of the carton 10′. This to some degree protects the reinforcing belt. Having now described the invention in connection with particularly illustrated embodiments thereof, modi­ fications and variations of the invention may naturally occur from time to time to those persons normally skilled in the art without departing from the essential scope of the invention, and accordingly it is intended to claim the same broadly as well as specifically as indicated by athe appended claims.

Claims: 1. A high strength reinforced container comprising a corrugated carton structure including means forming sidewalls, a top closure and a bottom closure, charac­ terised by a wide reinforcing belt (19, 19′) having a pair of side edges and a pair of opposite ends, said belt being disposed effectively entirely peripherally around the sidewalls and secured thereto, said belt extending upward for a distance from substantially the bottom of said carton structure, and securing means securing the said opposite ends of said belt against relative move­ ment in belt loosening directions, said belt (19, 19′) comprising a non-woven backing material (20) to which is adhered a parallel array of yarns (21) extending length­ wise of said belt, said yarns being of a type which exhibits minimal elongation under tension, and wherein said securing means comprises a patch (24, 24′) made of the same material as said belt, said patch having upper and lower side edges and being adhesively secured to said belt with the yarns of the patch and belt being disposed in facing relation and sandwiched between the backing material of said belt (19, 19′) and patch (24, 24′). 2. A container as claimed in claim 1, wherein said carton structure includes a corrugated carton (10) having sidewalls (12), and a tubular liner (15) having sidewalls,the liner being disposed within said carton with the liner sidewalls in flatwise surface engagement with the inside surfaces of the carton sidewalls. 3. A container as claimed in claim 1 or 2, wherein said carton structure includes a corrugated carton (10) which comprises said means forming the sidewalls (12), a top closure (11) and a bottom closure (13, 14),the belt (19) being disposed around the carton sidewalls (12), externally thereof and secured thereto. 4. A container as claimed in claim 2, wherein the liner (15′) comprises said means forming the sidewalls, the belt (19′) being disposed around the liner sidewalls externally thereof and secured thereto. 5. A container as claimed in any preceding claim, wherein said opposite ends of said belt are disposed in substantial abutment, and said patch is adhered flatwise to said belt on opposite sides of said abutment. 6. A container as claimed in claim 5, wherein the opposite ends (23) of said belt (19, 19′) are disposed on a flat sidewall surface of the sidewalls of said carton structure to which the belt is secured, and said patch (24, 24′) is adhered to said belt and is disposed on said flat sidewall surface of said carton structure. 7. A container as claimed in any of claims 1 to 5, wherein at least two adjacent portions of the sidewalls of said carton structure to which the belt is secured meet along a generally vertically extending line, wherein said opposite ends of said belt substantially meet from opposite directions at said generally vertically extending line, and wherein said patch is adhered flatwise to said belt and overlapping the ends thereof on opposite sides of said generally vertically extending line. 8. A container as claimed in any preceding claim wherein said belt is substantially one half to two thirds the height of said carton structure. 9. A container as claimed in any preceding claim, wherein the width of said patch between its upper and lower side edges is substantially the same as the width of said belt between its side edges. 10. A container as claimed in any preceding claim, wherein said yarns (21) are spaced closely together in parallel array at the edge of said belt nearest the bottom of the carton structure, are relatively widely spaced at the upper edge of said belt, and are contin­ uously graded in spacing density between the two edges of said belt. 11. A container as claimed in any preceding claim, wherein the non-woven backing material (20) of the belt is made of polyester material and said yarns are made of fiberglass. 12. A container as claimed in any preceding claim, including a bottom pad (17) fitted inside the carton structure and adhered to the inside surface of the bottom closure of the structure. 13. A method of reinforcing a container against rupture and excessive deformation by utilization of a lengthwise substantially inextensible wide fabric belt (19, 19′) having a pair of laterally spaced apart side edges and a pair of opposite ends and being of a type com­ prising a non-woven backing material (20) to one surface of which is adhered a parallel array of yarns (21) extending lengthwise of said belt, said yarns being of a type which exhibits minimal elongation under tension, being spaced closely together in parallel array at one edge of the belt, being relatively widely spaced at the other edge of the belt, and being continuously graded in spacing density between the two edges of the belt, said container being of the type comprising a corru­ gated carton structure including means forming sidewalls, a top closure and a bottom closure, the method being characterised by the steps of, a) disposing said fabric belt (19, 19′) length­ wise effectively completely peripherally around the sidewalls with the edge with closely spaced yarns positioned substantially at the bottom of the sidewalls and the edge with the widely spaced yarns positioned upward there­ from, and with the backing material (20) disposed flatwise against the surface of the sidewalls, b) adhesively securing the belt backing material (20) to the sidewalls in the position afore­ said, and c) securing the opposite ends of the belt against relative movement in belt loosening direc­ tions by adhesively securing to the belt a patch (24, 24′) made of the same material as the belt with the yarns of the patch and belt being disposed in parallel facing relation and sandwiched between the backing material of said belt and patch. 14. A method as claimed in claim 13, wherein said carton structure includes a corrugated carton (10,10′) having sidewalls, and a tubular liner (15, 15′) having sidewalls, the method including disposing the tubular liner within said carton in flatwise surface engagement with the inside surfaces of the carton sidewalls. 15. A method as claimed in claim 13 or 14,wherein said carton structure includes a corrugated carton (10) which comprises the means forming the sidewalls (12), top closure (11) and bottom closure (13, 14), the method including disposing the belt (19) around the carton side­ walls and adhesively securing the belt backing material to the carton sidewalls. 16. A method as claimed in claim 14, wherein said tubular liner (15′) comprises the means forming the sidewalls, the method including disposing the belt (19′) around the liner sidewalls, adhesively securing the belt to the liner sidewalls, securing the patch (24′) to the belt, and then installing the liner (15′) in the carton (10′).

Inventors: SYKES, HARRY P.
Applicants: WALNUT INDUSTRIES, INC.
Application year: 1986
Main classification: B65D63
IPC codes: B65D5, B65D63