WO2000076861A1

WO2000076861A1 - Package having body formed by folding and interconnecting two blanks

Info

Publication number: WO2000076861A1
Application number: PCT/SE2000/001127
Authority: WO
Inventors: Erland Eriksson
Original assignee: Sca Packaging Sweden Ab
Priority date: 1999-06-14
Filing date: 2000-05-31
Publication date: 2000-12-21
Also published as: SE9902226D0; SE516292C2; SE9902226L; AU5582600A

Abstract

Package made of corrugated board and consisting of a bottom-provided inner part (10) and a bottom-provided outer part (11), especially suitable as a package for shipping fish. These parts are dimensioned so that together they afford a strong package with multi-layer walls, and they are obtained from plane blanks which are punched out in one piece and provided with fold lines. The ends of the package consist of three layers (g, g1, g2') of corrugated board and include a first (g1) and a second (g2') wall panel constituting part of the outer part (10). The third layer is formed by a wall panel constituting part of the bottom-provided inner part (10) and is arranged between the said first and second wall panels. At the top, the first and second wall panels are held at a distance from each other by means of an essentially horizontal transition portion (g2'') formed in one piece with these wall panels. The said first (g1) an second (g2') wall panels form between them a space leading down towards the bottom of the assembled package, and the second wall panel (g2') is fixed to the inner bottom (b) of the assembled package.

Description

TITLE

Package having body formed by folding and interconnecting two blanks.

FIELD OF THE INVENTION The invention relates to a package made of corrugated board. To be more precise, it relates to a package made up of inner part and outer part, the assembled package forming a strong, multi-layer structure.

PRIOR ART Package constructions made of corrugated board have for a long time been successfully used to produce strong, cost-effective packages, in particular for use as shipping packages.

An example of a package construction based on corrugated board, made up of an inner part and outer part, and intended as a package for shipping fresh fish, is described in US 4,046,309. This package consists of a bottom- provided inner part, a bottom-provided outer part and a lid.

The part forming the inner part is in principle a so-called slotted box, i.e. the type of construction which has long been used as the best way of utilizing the material properties of corrugated material. In this connection, the blank is punched out in such a way as to ensure that, in the package or box which is obtained, the longitudinal orientation of the corrugations lies in the direction in which the stress is greatest, i.e. normally in the vertical direction.

The bottom-provided outer part in the known construction is made from a flat blank, and, at each of the opposite ends of a bottom panel and pairs of side panels contiguous with the latter, there are three adjacent subsidiary panels which are separated by punch lines and which together are intended to form an end wall made up of three material layers. Since, when producing the package from the said starting state of the flat blank, alignment of the corrugations in the longitudinal direction of the material in all three subsidiary panels is not possible, the outer part does not have the strength at the end walls which an alignment of the corrugation would be able to give.

The three end-wall subsidiary panels are laid closely against each other and the outer subsidiary panel has an extended portion which is folded over the top edge. Flaps in grip openings in the inner and central subsidiary panels are, like a flap in the extended portion, introduced into a lock opening in the outer subsidiary panel and hold the outer part in the erected state.

The inner part and the outer part are held together by a flap in each outer end-wall subsidiary panel of the outer part extending through a respective grip opening and bearing by friction directly against the respective end wall of the inner part.

The package known from US Patent Specification 4,046,309, made of corrugated board and consisting of an inner part and an outer part, is complicated to produce. Industrial production of the complicated blanks constituting the starting material for inner part, outer part and cover requires sophisticated and therefore expensive machinery. The material can only be produced, and in principle also used, where such machinery is available, or at a limited distance from this. In fact, the reality is that, for economic reasons, finished blanks for corrugated-board shipping packages cannot be transported over long distances from production site to end-user.

Distribution of food is a well-known global problem. Foods are produced and/or exist as natural resources in many different parts of the world, but, unfortunately, many such places do not have the resources or means needed for extensive investments, for example those needed for industrial production of shipping packages in accordance with what is known from US 4,046,309.

Another problem concerning food distribution, for example by air freight, is that the distribution packaging must be liquid-tight. The package known from US 4,046,309 is deliberately constructed to let out the melt water from ice which is used for cooling the shipped product. For this purpose, run-off openings are provided both in the inner part and the outer part. In addition, the construction of the inner part, which in principle is a so-called slotted box, does not give any possibility of making the package either liquid-tight or vapour-tight. Nor can the inner part (slotted box) in the known construction be replaced for another construction, since, as is set out in the description of the patent specification, it is a necessary component for permitting subsequent filling with ice as required. This is because the filling operation involves the lid first being removed, the assembled package being turned upside down, the outer part being removed, after which the bottom closure of the slotted box (inner part) is opened up and new ice is introduced into the bottom of the inner part, whereupon it is returned to the initial state in reverse sequence.

In addition to the said problems concerning the complicated and expensive production equipment, the non-optimal utilization of the strength that can be achieved with corrugated board, and the problems where the method of shipping requires that the package be liquid-tight, there are further problems with the construction according to US 4,046,309 in case there are requirements in terms of good barrier characteristics, for example tightness to water vapour, which it is impossible to achieve using the known construction. The latter cannot be used or modified to give the packaged product any longer storage life than that which can be achieved by cooling with ice.

A further example of a shipping package made of corrugated board is disclosed in German OS 2,262,539. This package is intended for fresh fish and is a single-layer construction made of strong corrugated board. The package is especially designed to allow melt water from ice to run off. The construction lacks the requirements needed to provide barrier characteristics. Japanese Patent Publication 10-273131 describes a single-layer shipping container intended for fresh fish and made of corrugated board. The construction is based on the tray construction traditional in the solid carton technology, with so-called external delta corner flaps which are formed in one piece with associated end wall panels and side wall panels and thus do not expose any cut edges towards the inside of the tray. The single-layer construction of corrugated board requires strong material to give the necessary strength, especially as alignment of the longitudinal direction of the corrugations is only possible in two opposite sides of the tray obtained from the flat blank. The tray has a lid which can be pressed onto the top of the tray and is held in place by elastically resilient hand grips on the end walls. The bearing surface between the lid and the top of the tray is small, especially along the long sides. Thus, in practice, it is not possible to achieve liquid-tight and in particular vapour-tight closure.

In the area of solid carton technology, there are a number of different constructions consisting partially of inner and outer parts, but not intended to form strong shipping packages, nor intended to permit sealing/closing against liquid and vapour.

US Patent Specification 2,414,703 discloses a solid carton package, intended especially for shoes, in which a peripheral banderole, possibly provided with cover, has been combined with a tray. The construction thus has a single layer of solid carton as bottom. By means of the end wall flaps of the tray being extended, three material layers are obtained in the end walls. The banderole forms the central layer and the tray is held upright by means of lugs on the extended end-wall flaps. These lugs are introduced for locking engagement in punches in the edges of the side walls.

OBJECTS OF THE INVENTION

One object of the invention is to use a corrugated board as material for a package and to produce a strong package construction which can be produced industrially with relatively simple production machinery and which, by virtue of its basic construction, can be made liquid-tight and vapour-tight.

Another object is to make available an improved, cost-effective alternative to the shipping packages mentioned at the outset and intended for fresh fish, the said improvement eliminating the shortcomings which have been mentioned concerning the known constructions.

Yet another object is to make available a shipping package which satisfies stringent demands placed on transportability, including demands concerning air transport.

The object is, in the final analysis, for the production source of the packaging material to be brought geographically close to the production source for the product which is to be packed in the shipping package.

THE INVENTION

The said objects of the invention are achieved with a package construction of the general type set out in the introductional clause of Patent Claim 1 , and with the features set out in the characterizing clause of the said claim.

Further developments of the basic concept according to the said claim and preferred embodiments are set out in the dependent claims.

BRIEF DESCRIPTON OF THE DRAWINGS

Figures 1a - 1c show component elements and stages which result in a package made up of inner part and outer part according to a first embodiment of the invention,

Figure 1d is a cross section through the closed and sealed package according to the first embodiment, and it shows the principle of the end wall construction of the package, Figures 2a - 2c show component elements and assembly stages which result in a package made up of inner part and outer part according to a second embodiment of the invention,

Figure 2d is a cross section through the closed and sealed package according to the second embodiment, and it shows the principle of the end wall construction of the package,

Figures 3a - 3c show component elements and assembly stages which result in a package made up of inner part and outer part according to a third embodiment of the invention,

Figure 3d shows a cross section through the closed and sealed package according to the third embodiment, and it shows the principle of the end wall construction of the package,

Figures 4a - 4c show component elements and assembly stages which result in a package made up of inner part and outer part according to a fourth embodiment of the invention,

Figure 4d shows a cross section through the closed and sealed package according to the fourth embodiment, and it shows the principle of the end wall construction of the package,

Figure 5 shows a flat blank intended to form the outer part of the assembled package, and

Figure 6 shows a flat blank for the inner part of the assembled package according to Figures 2 - 2d. DESCRIPTION OF EMBODIMENTS

Figure 1a shows a component element for an assembled package. This component element constitutes an inner part 10 in the form of tray obtained from a flat blank of corrugated board. Except for long side flap panels, the blank has the same configuration as the blank in Figure 6, i.e. the blank for the inner part in Figure 1a comprises a bottom wall panel b, opposite pairs of long side wall panels I, opposite pairs of short side or end wall panels g and corner panels d , c2. These panels are designed from a blank which has been punched out from corrugated board and whose corrugations in the longitudinal direction are oriented as shown by the lines D and are contiguous with each other via fold lines or lines of weakening w1-w7. As can be seen from Figure 1 a, the corner panels d , c2 of the inner part are placed externally against associated short or end-wall sides and thus give a smooth inside, at the same time as the subsidiary panels, by virtue of their so-called delta corner construction, afford tightness and do not expose any free cut edges towards the inside of the inner part. In the inner part obtained, the longitudinal direction of the corrugations in the short sides or end walls is essentially vertical, as has been indicated by the lines D. Depending on the requirements placed in terms of tightness, the corrugated board material used for punching out the blanks can be coated, on one side or on both sides, with a suitable thermoplastic material, for example polyethylene, polypropylene or the like, to provide liquid tightness and a certain vapour barrier. If so required, more sophisticated coating material can also be used if higher degrees of barrier effect are desired, especially when the inner part is provided with long side wall flaps (e.g. according to Figures 2a - 2d).

Figure 1 b shows a component element of the assembled package in the form of an outer part 11. This outer part is obtained from a flat blank of corrugated board. The blank is, in its basic configuration, a blank for a so-called slotted box and is punched out using the same simple punching technique as is used for such boxes, and this, together with the uncomplicated punching out of the inner part in Figure 1a, provides a total concept which is well adapted to production plants using traditional equipment.

The blank for the outer part in Figure 1b, as well as for the outer parts in the other embodiments illustrated, is shown in Figure 5. It comprises panels g1 , 11 forming side walls, panels or flaps b1, b2 forming a bottom, panels or folds t1 forming a top, a join panel f, and panels or flaps g2 intended for a special purpose which will be described later.

The blank is punched out from corrugated board material, with the longitudinal direction of the corrugations oriented as indicated by the lines D. The left-hand panel 11 in Figure 5 is contiguous with associated top and bottom panels or flaps and the panels g1 via the fold lines or lines of weakening w8-w11. The right-hand panel 11 is contiguous with associated top and bottom panels or flaps and the right-hand panel g1 via fold lines or lines of weakening w8, w10 and w11. The join flap f is intended in a traditional manner to be folded about its fold line w9 and, upon folding of the blank about the other fold line w9, to be fixed, for example glued, to that side of the right-hand panel 11 in Figure 5 which is intended to form the inside of the outer part 11.

The panels b1 , b2 and t1 and g2 have also been called flaps, for the simple reason that, in the flat state of the blank in Figure 5, they are separated from each other by slits s. In the embodiment shown in Figure 5, these slits extend from a respective imaginary line, which is defined by the free boundary edges d1 and d2, respectively, of the flaps t1 , g2 and b1 , b2 at right angles to the level of the respective set of fold lines w8, w12 and w10, w13. For reasons which will later become apparent, in certain embodiments the slits between the flaps t1 and g2 should have a width a least equal to the material thickness of the part forming the inner part of the assembled package. In the embodiment shown in Figure 5, the side wall panels g1 are intended to form the end walls or short sides of the outer part. In the panels g1 there are punch lines and weakenings h intended to form a carrier handle for the assembled package.

The vertical height of the outer part 11 is defined by the distance between the sets of fold lines w8, w12 and w10, w3, respectively. As has already been mentioned, the flaps g2 and t1 in the embodiment in Figure 5 are the same length, which is advantageous from the production point of view, but not an absolute condition. For reasons which will later become apparent, it is by contrast important that the flaps g2 have a length which is greater than the vertical, inner height of the outer part 11 minus the material thickness of the inner part.

In each flap panel g2 there is a fold line or line of weakening w14 parallel to the line w12. The distance at right angles from the line w14 to the free end edge d1 of the flap g2 is at least equal to but preferably greater than the distance between the lines w12 and w13 minus the material thickness of the inner part 10.

Formed between the lines w12 and w14 there is a first subsidiary area g2" of each flap panel g2. These subsidiary areas, like the areas g2' between the fold lines w14 and the end edges d1 , are of great importance for the packaging construction as a whole, as will be explained later.

Now that the component elements in the embodiment according to Figures 1a-1d have been described, a description will be given of the package according to Figures 1a-1d consisting of inner part and outer part.

The inner part 10, whose external bottom format essentially corresponds to the internal bottom format of the outer part 11 , is lowered into the outer part whose bottom has been closed. The bottom closure of the outer part can be effected in a traditional manner, for example with tape or staples. The inner part has a height essentially corresponding to that of the outer part. The side edges s' of the opposite end flaps g2 of the outer part, which, because of the positioning of the slits s and the fold line w9, are drawn in slightly relative to the insides of the side walls 11 , permit folding-in of the flaps g2 towards the bottom b of the inner part 10, firstly about the lines w12 and then about the lines w14. Because the length of each flap g2 between the line w14 and the end edge d1 of the flap has been dimensioned in the manner indicated, the end edge d1 of each flap g2 can be snapped past an unstable position, where the subsidiary area g2' is essentiallly vertical, to a stable position according to Figure 1d. In this position, the inner part 10 is held stable and fixed against the bottom of the outer part.

A hollow space is formed between each flap g2 and associated end wall panel g1. The flap and the end wall panel in principle form a stable hollow beam. Since the longitudinal direction of the corrugations in the material of the end wall panel g1 and the part g2' are aligned, i.e. vertical, a construction is obtained which withstands high vertical loads. The end wall g of the inner part contributes to this, as it too has the longitudinal direction of the corrugations oriented vertically.

The beam construction at each end wall also provides an essentially horizontal and very stable transition portion g2". This portion is used to seal the long side flaps t1 to the beam surfaces g2" in the transverse direction of the assembled package, i.e. along the end wall. In the longitudinal direction, the flaps t1 are sealed in an overlap area t1 '.

The sealing can be made extremely tight and can be effected by heat-sealing of thermoplastic material which has been coated in advance onto the material, or another type of sealing can be used, for example using hot melt, cold-sealing adhesive or tape. In certain applications, it may be necessary to have tighter sealing than is possible in the embodiment according to Figures 1a-1d. Such a design is shown in Figures 2a-2d. The difference from the illustrative embodiment in Figures 1c-1d is that the inner part is provided with long side flaps cl. Otherwise, the outer part is unchanged and the arrangement of flaps created by slits affords, in the same way as before, the possibility of placing the inner part in the outer part and thereafter folding the flaps g2 down, in this case with the difference that the long side flaps cl extend upwards from the inner part 10 and give the edge area cl'. It should be noted that each long side flap cl has an extent in the longitudinal direction equal to the internal length of the long wall 11 of the outer part. In this way, the long side flap of the inner part extends as far as the corners of the assembled package.

With the edge areas cl', the long side flaps cl of the inner part are sealed against the horizontal transition area g2" and the flaps cl are sealed against each other in a transition area cl". In the illustrative embodiment according to Figures 2a-2d, the inner part is made from a blank which is shown in Figure 6. Although such a blank gives optimum tightness and is also easy to handle, other variants of inner parts and of blanks for these are nevertheless also possible.

Thus, Figures 4a-4d show a variant of an inner part where the long side flaps cl are slightly shorter in relation to the long side flaps according to Figures 2a-2d which extend out to the corners of the assembled package. In addition, the long side flaps are of different lengths from each other. Otherwise, the construction corresponds to what has already been described, but, as in Figures 1a-1d, the horizontal transition areas g2" are used only for sealing the long wall flaps t1. This type of assembled package permits better sealing properties than the package in Figures 1a-1d.

Finally, Figures 3a-3d show a further variant of the inner part. This has only one long side flap cl, and the latter is of shorter length than the inner wall 11 and cannot therefore be sealed against the horizontal transition area g2" of the beam constructions in the assembled package.

The described embodiments afford a strong package construction of corrugated board which can be produced using simple production means and which, by means of its basic construction, is well suited as a liquid-tight and vapour-tight shipping package, for example for fresh fish. The package also satisfies stringent demands placed on transportability, including air transport, and can thus be used for food products which require rapid handling. At the same time, however, the storage life of the packed food can be considerably lengthened by suitable coating of the corrugated material with a barrier material. Since the package can be made tight by means of the sealing possibilities alone, such coating with a material creating a barrier against water and vapour is completely defensible.

Although the invention has been described with reference to illustrative embodiments, it will be appreciated that further alternatives and modifications are possible and that the invention is limited only by what is specified in the attached patent claims.

Claims

PATENT CLAIMS

1. Package made up of a bottom-provided inner part (10) and a bottom-provided outer part (11 ), both parts consisting of corrugated board and being dimensioned so that together they afford a strong, assembled package with multi-layer walls (I, 11; g, g1 , g2') and a multi-layer bottom (b, b1 ), and where each of the parts are obtained from plane blanks which are punched out in one piece and provided with fold lines (w1-w7, w8-w14), and at least one pair of essentially vertical, opposite side walls of the assembled package comprise three layers of corrugated board (g, g1 , g2'), including a first (g1) and a second (g2') wall panel constituting part of the outer part, and which, at the top, are held at a distance from each other by means of an essentially horizontal transition portion (g2") formed in one piece with these wall panels, characterized in that

the third layer (g) is formed by a third wall panel, constituting a direct continuation of the bottom of the bottom-provided inner part (10) and arranged between the said first and second wall panels,

and in that the said first (g1 ) and second (g2') wall panels, down towards the bottom of the assembled package, form between them a space which takes up the said third wall panel,

and in that the second wall panel (g2') is fixed to the inner bottom (b) of the assembled package.

2. Package according to Claim 1 , characterized in that the essentially horizontal transition portion (g2") extends between a pair of parallel fold lines, a first (w12) of these coinciding with the upper edge limit of the said vertical side wall (g1 ), and, vertically between the second fold line (w14) and the inner bottom (b) of the inner part (10), a distance is defined which is less than the length of the second wall panel (g2') at right angles from the said second fold line (w14).

3. Package according to Claim 2, characterized in that the said at least one pair of essentially vertical opposite side walls (g, g1 , g2') form the short sides of the assembled package, in that the outer part (11), on opposite long sides, is provided with mutually overlapping long-side flaps (t1 ) which extend in the longitudinal direction essentially as far as each respective one of the said first fold lines (w12), and in that the said flaps are sealed against each other in the longitudinal direction in the overlap area (t1') and, in the transverse direction, are sealed against each respective one of the said transition portions (g2").

4. Package according to Claim 3, characterized in that the inner part (10) is designed as a tight inner package, entirely without free, inwardly directed cut edges, for example in the form of an inner part with externally placed delta corner panels (d , c2).

5. Package according to Claim 4, characterized in that the material of the inner part is coated with thermoplastic forming a vapour and liquid barrier, at least on that side facing inwards.

6. Package according to any of Claims 3 to 5, characterized in that the inner part (10) is provided, on opposite sides, with mutually overlapping long-side flaps (cl) which extend in the longitudinal direction essentially as far as each respective one of the said first fold lines (w12), and in that the said flaps are sealed against each other in the longitudinal direction in the overlap area (cl") and, in the transverse direction, are sealed against each respective one of the transition portions (g2").

7. Package according to one or more of Claims 1 to 6, characterized in that the inner part and/or outer part is/are coated with heat- sealable thermoplastic material, at least in the said transition portions (g2") and on any overlapping wall/bottom flaps intended for sealing.

8. Package according to one or more of Claims 1 to 7, characterized in that the outer part is made in the form of a so-called slotted box.