WO1993009032A1

WO1993009032A1 - Blank for forming a box

Info

Publication number: WO1993009032A1
Application number: PCT/GB1992/001930
Authority: WO
Inventors: Stephen Woodthorpe Clarke; Edward Philip Bacon; Egon Magne Engesaeth
Original assignee: Cairway Limited
Priority date: 1991-11-06
Filing date: 1992-10-21
Publication date: 1993-05-13
Also published as: GB9123550D0; IS3942A; AU2763992A

Abstract

A blank (20) of material such as extruded plastic sheet material has multiple thickness side panels (21, 22) and corner flaps (27) so that when the blank is erected to provide a box for transport of produce such as fresh fish, a corner of the box is virtually rigid and uncrushable as it is formed of multiple layers of substantially parallel material of the blank.

Description

BLANK FOR FORMING A BOX The invention relates to a blank, particularly a blank of relatively rigid sheet material which is erectible to form a box, pack, container or the like.

In the past, packs for produce, particularly fresh fish, have been made from polystyrene. However, such packs are of unitary construction, cumbersome and prone to failure as, being brittle, they are prone to break. This is environmentally unacceptable, expensive, and has the additional disadvantages of tending to spill the produce, and of contamination of the produce with particles of the pack. Further, polystyrene is also not recyclable.

It is an object of the invention to seek to mitigate these disadvantages.

According to a first aspect of the invention there is provided a blank of relatively rigid sheet material for erection to form a box or the like, comprising parts which in the erected blank form corners of the box and comprise multiple thicknesses of the sheet material.

The blank may be substantially rectangular and there may be at each corner thereof two sets of parts. This provides for added strength at the corner of an erected box.

The multiple thicknesses of material forming the parts may be secured together by local fusion, for example by an ultrasonic weld. This provides a firm and positive connection using the material to secure itself together without the need to use connectors such as staples, which are expensive and can cause contamination of products if they rust, and are also dangerous, being sharp. The sets may be connected by flexible connectors. This provides for ease of erection.

One of the sets of parts may comprise flap parts and one of these flap parts may be secured to an underlying part and the other flap part may be relatively movable with respect to the underlying part and may be hingedly connected by an integral hinge line with the first flap part. This provides for ease of erection and strength in the assembled box.

The other flap part may be hingedly connected with a part which is erectible to extend at substantially 90° to a base part when the blank is erected and the sets of parts lie adjacent one another. This provides for a rigid construction.

The sheet material may include cooperable locking means which maintains the blank in an erected position. This enables the erected box to be self-sustaining without the need to employ additional erection means on assembly of the blank.

The cooperable locking means may comprise a plurality of complementary tongue and slot means. This is a relatively simple interengageable construction.

The blank may be a unitary blank made from an extruded fluted plastic material, suitably polypropylene.

According to a second aspect of the invention, there is provided a box erected from a blank as hereinbefore defined.

The box may include an insert. This is a simple mounting arrangement for an insert. There may be an absorbent pad below an insert in the box. This helps to absorb moisture from produce.

There may be a removable lid which is erected from a blank similar to the blank from which the box is erected. This provides for ease of use, and assists in keeping produce clean.

The box may have inwardly tapered corners. This prevents bowing or gaping of the sides between corners and therefore helps to maintain produce in the box.

Boxes embodying the invention are particularly suitable for the storage and transport of produce, particularly fresh fish.

Boxes embodying the invention are hereinafter described, by way of example, with reference to the accompanying drawings.

Fig.l is a schematic view of an end of a box according to the invention;

Fig.2 is a plan view to a reduced scale of a blank from which the box of Fig.l is erected;

Figs. 3 to 6 show different steps in an erection procedure.

Fig.7 is a plan view of the interior of a blank prior to assembly to form a box in accordance with the invention;

Fig.8 is a plan view of one panel of the blank of Fig.7;

Fig.9 is an end elevational view of the panel of Fig.8; Fig.10 is a schematic view of one corner of the blank of Fig.7 during erection to form a box according to the invention.

Fig.ll is a plan view of the interior part of a further embodiment of a blank prior to assembly to form a box in accordance with the invention;

Fig.12 shows a blank for erection to form a lid; and

Fig. 13 is a perspective view of an insert or shelf.

Referring to the drawings, there is shown a box 1 erectible from a blank 2 which is a die cut blank of relatively rigid sheet material, suitably an extruded fluted plastic sheet material which is securable to itself by local fusion when parts thereof are overlapped. The blank 2 has parts which in the erected pack extend substantially at right angles to one another and which parts are secured together by local fusion, for example by welding such as ultrasonic welding, whereby to allow relatively rapid assembly of the pack 1.

The fusion or welding may be accomplished by inserting the overlapped parts between ultrasonic welding heads and welding at points indicated by X and X' in Figs. 1 and 4.

The blank 2 comprises a base panel 3 of the erected blank, opposed pairs of parts or panels 4 along opposite longitudinal sides of the base 3 and further pairs of panel parts 5 which are at opposite and at right angles to the first pair of opposed panel parts 4 and form ends of the erected box 1.

It will be understood that the blank 2 has various appropriately positioned hinge or crease lines 6 formed therein as by welding or cutting whereby to connect the respective panel parts 4, 5 to the base 3 and about which those panel parts 4, 5 are folded out of the plane of the base 2 whereby to erect the pack 1.

The description of the invention will be confined to one part of one end, Fig.1 as all are identical.

The respective side panel parts 4 have at each end an extension flap 7 which is part cut through to provide two parts 7a, 7b which both overlap an adjacent end panel part 5. The part 7b is secured to the end panel part by welding at X, and the parts 7a, 7b are separated by an inclined cut line 8 whereof the part 7a, which is also hinged to the part 5 and to the side panel 4 at 6' can move towards and away from the end panel part 5. Thus to erect the blank 2, as the side 4 is moved up to 90° to the base 2, the part 7a is drawn up too, away from the cut 8, and this pulls the part 7b, and hence the end part 5 to which it is welded, up, so facilitating a rapid erection. The end panel part 5 is in two parts 5a and 5b the part 5b having an overlapped flap 9 secured by welds X' to provide a rigid structure and thus a strong pack 1. The flaps 7b, 9 are connected by an integral element 10 which assists in the connection of the parts 5a, 5b and which is folded in on itself when the end part 5 is folded down on itself about hinge 6" to provide a sturdy end of the pack, a tongue 11 being received in a slot (not shown) in the base 2.

It will be understood that the blank may be delivered pre-welded and folded flat, for rapid erection on site as described herein.

Fig.2 of the erection step is optional and used only when there are three end panel parts 5a, etc. If there are not, the folding procedure is as shown shaded in Fig.5, where the blank is shown in position for welding, at the weld points X, X' of Fig.4, whereafter the blank is shown in Fig.6 folded flat for delivery, though this is optional, the blank could be delivered in the Fig.4 position.

Referring now to Figs. 7 to 10, there is shown a blank 20 which is also erectible to form a pack, box or container for produce, particularly fresh fish. The blank 20 is shown, in Fig.7, in a position prior to erection, that is opened out or substantially flat. It is in this condition that the blank 20 is produced in an assembly process prior to sale and delivery to a point of use, such as on board a trawler, or on a fish dock. The blank 20 is formed from extruded fluted plastic sheet material. The blank has two side panels 21, 22 respectively comprising an inner 21 and an outer one 22 as considered in a direction from a part 23 of the blank which is a base of the pack, there being two pairs of inner and outer side panels forming a first pair of opposite sides of the blank 20. The base part 23 is connected to the inner side panel by a crease line 24 formed in the blank 20 by any suitable means such as cutting or heating. The inner side panel 21 is connected with the outer side panel 22 by two spaced crease lines 25 which are substantially parallel to one another, and to the crease line 24. The outer side panel 22 comprises two thicknesses 26 (Fig.9) of the blank, bent over about crease lines 27 so that the one thickness 26 shown in Fig.7 overlies an under panel which is in effect a continuation of the base part 23. The outer side panel 22 also has what becomes a comer flap 27 at each comer. Each comer flap is bent in about crease lines 28 at a boundary of the blank 20 as shown, (Fig.7) and itself comprises a double thickness 29 of the sheet material folded back on itself so that the layer shown overlies an under layer. Thus it will be appreciated that at each comer of the blank shown, there are four thicknesses of the sheet material of the blank, comprising the two thicknesses of the outer side panel 22, and the two thicknesses 29 of the comer flap 27. The four layers or thicknesses are secured together by any suitable means, for example an ultrasonic weld 30. At the crease lines 27 about which the outer side panel part 26 is folded are formed spaced slots which provide projecting tongues 31 when the outer side panel part 26 is folded to the inner (left as viewed in Fig.9) position shown. These tongues 31 are aligned with through slots 32 at the crease lines 24.

Along facing opposite sides, or ends of the base part 23, at right angles to the first opposite pairs of side panels 21, 22 is a second pair of opposite side panels 33, which overlie the material of the base part 23. Again describing one of these and concentrating on one end, the blank is folded over to overlie the base part to provide an end wall 33 in the erected box, connected by a crease line 34 with a part which has a diagonal, 45°, crease line 35 so that two flap parts 36a and 36b are provided, one of which 36a like the part 33 is not attached to another part except by crease lines, and the other of which 36b is secured to the underlying blank material by suitable means such as an ultrasonic weld 37 and an integral flexible strap tongue or strip 38 of material which is also connected with the top or inner layer 29 of the comer flap 27. Underneath the end wall 33, though not shown in Fig.7, are two more slots 32, respectively aligned with the outermost tabs or tongues 31.

The outermost face (in Fig.7) of the outer side flap 22 has a plurality, in the embodiment three, cut-outs 39 which are aligned, shown in Fig.8.

In use to erect a box from the blank 20 of Fig.7, firstly the inner and outer side panels 21 and 22 are raised, out of the plane of the paper of Fig.7, that is towards the viewer, about crease line 24, as shown by arrow 'A', Fig.10. This action causes the end wall 33 to pivot up automatically off the base part 23 about the crease line 28 as shown by arrow 'B'. Simultaneously, the flap part 36b is raised too, off the base part 23, so that that flap part pivots about the diagonal crease line 35 towards the flap part 36b which is secured by the weld 37 to the underlying part of the blank so cannot lift off. When the inner and outer side panels 21 and 22 are at 90°, or substantially so, to the base part 23, the flap part 36a is parallel to and in contact with the flap part 36b. The outer side panel 22 is now turned down inwardly (that is towards the inner volume of the box) to overlie and lie in parallel to the inner side panel 21. When it is in this position, the tongues 31 become engaged automatically in the slots 32, the folding being allowed by the double crease lines 25, and by suitable flexure of the tongues or strips 38 of material. It will be understood that the first pair of opposite sides are lifted simultaneously so that the box is erected very quickly, in a matter of a few seconds, and is a firm, stable rectangular configuration. Moreover at each comer, the most vulnerable part of the erected box there is a particularly strong and virtually rigid construction provided by seven layers of the material of the blank 20, namely the two layers 26 of the outer side panels, the two layers 29 of the comer flap 28, the two layers of the parts 36a, 36b and the layer of the inner side panel 21. This produces six layers of vertical flutes, the flute direction being shown at Y.

Referring now to Fig.ll, only one side of an alternative blank 40 is shown. This blank 40 is similar to the blank 20 of Fig.7, and therefore like parts are identified by like reference numerals. In this embodiment, however, the flap parts 36a and 36b are modified. In Fig.ll, the flap part 36a is separated from the flap part 36b by a cut 41 extending from a free edge 42 of the flap part 36a into the body thereof and then terminating at the start of a diagonal hinge or crease 43 as before. There are also distinct cut-outs or through holes 44 in the base part 23 adjacent the crease line 24, rather than slits or slots as in Fig.7. Otherwise the construction is virtually identical to that of Fig.7. The operation of erecting the blank to form the box is virtually identical too. In the Fig.ll embodiment raising the opposite pairs of side panels 25, 22 about the crease line 24 is accommodated by the flap part 36a lifting off the underlying sheet material (inner side flap) and folding outwardly about the crease line 43, as shown by the arrow 'E'. This action in turn raises the end flap part 33 off the base part 23, the end flap part 33 being continuous with the flap part 36a. When the opposite pairs of side panel parts 21, 22 are at 90° to the base part, or substantially so, the outer side panels 22 are folded down about the crease lines 25 so that the tabs or tongues 31 engage in the cut-outs or notches 44 to provide a stable, rigid box. It will be understood that as with the Fig.7 embodiment, the opposite pairs of side panels are raised to the 90° position in relation to the base part 23 and that as with the Fig.7 embodiment, the opposite end panel parts 33 are automatically raised to form end walls of erected box, as before in Fig.7. In Fig.ll too, the comers 27 are strong and virtually rigid, being composed of seven layers of sheet material substantially in parallel, namely two layers each of the outer side panels, and comer flaps, the inner side panel layer, and the flap parts.

A blank 50 for a lid for the Fig.7 embodiment is shown in Fig.12. The construction of this lid blank is similar to that of the box itself (Fig.7) and like parts are referred to by like numerals. In the case of the blank 50, the inner and outer side flaps 21 and 22 are both of single thickness of the sheet material, and the comer flaps 27 are not folded in initially, and are of single thickness too, being connected with flap part by an outer tongue 51 and separated from that flap part by a cut out 52. There is also only one tongue 31 engageable in a slit 32 of trapezoidal form extending inboard of the crease or hinge line 24. Erection to form the lid is by folding up opposite side panels, or the opposite panels 21, 22 and folding the outer side panel 22 over the inner one 21 about crease lines 25 to lock the tongues 31 in their respective notches 32, the flexible straps or tongues 51 pulling up the inner side panel 36b part when the panel parts are raised.

A blank for a lid for use with a box erected from the blank of Fig.11 is virtually identical to that blank 40, except that the outer panel part is only one sheet material thickness and the flap is also of a single sheet material thickness. Also, there is only one tongue, as in Fig. 12, for tucking into a slit.

Both boxes erected respectively from the blanks of Figs. 7 and 11 can have an insert such as an absorbent pad (not shown) and/or a shelf 60 which itself can be erected from a blank of extruded fluted sheet plastic material. Fig. 13 shows a shelf 60 formed into a channel by folding up flaps 61 about crease lines 62 which automatically turns down tongues 63 out of notches 64. When the shelf 60 is inserted in the box (erected from the Fig.7 blank) the tongues 63 locate in the cut outs 39 (Fig.8) on the outer panel part 22, so tensioning the walls of the box apart and assisting in maintaining rigidity of the erected box. Any moisture such as melting ice or the like can then pass down through the notches 64 to an absorbent pad under the shelf.

It will also be understood that when erecting the blanks 20 or 40 the tongues or straps 38 automatically bring over the end 33 square because when the material is converted by cutting out which is necessary to give a smooth and flat fold, a slot is cut out to leave the strap or tongue so that the end of the box is pulled over with the rest of this side.

In all embodiments, the comers 27 are slightly offset to stop bowing out of the central part of the sides so that when the box is loaded, and the sides do bow, those sides bow out to the vertical and not beyond.

The offestting of the comers 27 is provided by providing that the end panels are not rectangular, but are slight trapezoidal by having the hinge lines 27 slightly tapered towards one another in a direction away from the base part 23 so that when erected the comers lean in. This ensures that when the box is loaded, the comers bow out to the vertical, and do not gape and enable produce to fall out. The lid is square so that it is initially loose as it is placed on the box, so that as the lid moves down, it becomes tighter and hence is held firmly in place. The welding used in the box blanks also aids assembly of the box, and strengthens the comers to provide a solid comer which does not flex and which therefore provides a stackable box.

A box made as hereinbefore described can be used to load up to 30% or more fish on a standard 'PF pallet, because the inventive boxes are not so bulky as previous polystyrene boxes.

Also, the number and position of the weld points 30, 37 may vary, and for example may be extended as weld strips.

Claims

1. A blank of relatively rigid sheet material for erection to form a box or the like, comprising parts which in the erected blank form comers of the box and comprise multiple thicknesses of the sheet material.

2. A blank according to Claim 1, the blank being substantially rectangular and there being at each comer thereof two sets of parts.

3. A blank according to Claim 2, the multiple thicknesses of material forming the parts being secured together by local fusion.

4. A blank according to Claim 3, the local fusion comprising an ultrasonic weld.

5. A blank according to any of claims 2 to 4, the sets being connected by flexible connectors.

6. A blank according to any of Claims 2- to 5, one of the sets of parts comprising flap parts, one of these flap parts being secured to an underlying part and the other flap part being relatively movable with respect to the underlying part and being hingedly connected by an integral hinge line with the first flap part.

7. A blank according to Claim 6, the other flap part being hingedly connected with a part which is erectible to extend at substantially 90° to a base part when the blank is erected and the sets of parts lie adjacent one another.

8. A blank according to Claim 7, the sheet material including cooperable locking means which maintains the blank in an erected position.

9. A blank according to Claim 8, the cooperable locking means comprising a plurality of complementary tongue and slot means.

10. A box whenever erected from a blank according to any preceding claim.

11. A box according to Claim 10, and an insert.

12. A box according to Claim 11 , including notches for receiving tabs of the insert whereby to maintain the insert in position in the box.

13. A box according to Claim 12, including an absorbent pad below an insert in the box.

14. A box according to Claim 13, including a removable lid which is erected from a blank similar to the blank from which the box is erected.

15. A box according to any of Claims 10 to 14, having inwardly tapered comers.