EP1586508A1

EP1586508A1 - Tray for containing foodstuffs and method for the realisation thereof

Info

Publication number: EP1586508A1
Application number: EP04103485A
Authority: EP
Inventors: Gianmario C/O Novacart S.P.A. Anghileri
Original assignee: Novacart SpA
Current assignee: Novacart SpA
Priority date: 2004-04-14
Filing date: 2004-07-21
Publication date: 2005-10-19
Also published as: ITMI20040733A1

Abstract

It is disclosed a holding tray for foodstuffs of the type consisting of a single portion of laminar material folded along folding lines (3) adapted to define a bottom wall (4), at least four lateral walls (5, 6), at least four angular junction regions (7) interposed between the lateral walls (5, 6) and end flaps (8) intended for overlapping corresponding edge bands (7a) of the angular regions to block them against a first pair of opposite lateral walls (5). Said lateral walls and the respective end flaps (8) have a substantially convex conformation with convexity facing the outside of the tray, so as to cause a steady mating engagement of said end flaps (8) with the outer surface (5a) of the corresponding lateral walls (5). Also provided is a method of manufacturing a holding tray for foodstuffs comprising the steps of cutting out, along a contour line (2), a single portion of laminar material and folding said portion along folding lines (3) adapted to form the tray itself. A first pair of opposite lateral walls (5) and the respective turned down end flaps (8) are submitted to a final operating step involving deformation to a curved shape with convexity towards the outside of the tray.

Description

The present invention relates to a holding tray for foodstuffs and to a method of manufacturing it.
It is known that holding trays for foodstuffs made of laminar paper material, usually thin paperboard coated on a face thereof with a film of plastic material such as polyethylene, are generally obtained starting from a single portion of said paper material of a convenient profile that is cut out at a suitable contour line and subsequently submitted to bending and folding operations along suitable lines adapted to define the different parts of which said trays are made.
More specifically, the folding lines delimit a bottom wall, usually of a substantially rectangular shape, four lateral walls and four angular junction regions interposed between the lateral walls and each consisting of two portions disposed in side by side relationship to be superposed upon each other and to be folded down against the outer surface of an adjacent lateral wall.
The above mentioned lateral wall belongs to a pair of opposite lateral walls having respective end flaps at their upper part which are adapted to be turned over as well against the outer surface of said walls. The function of the end flaps is to overlap edge bands of the above mentioned angular regions for the purpose of blocking said angular regions against said first pair of opposite lateral walls.
Practically in the known art a certain amount of adhesive material is used for the purpose of obtaining a steady engagement of the end flaps with the outer surface of the corresponding lateral walls and consequently also keeping the angular regions in a blocked condition against said outer surface so as to give the tray the required structural solidity.
The known art briefly described above has some limits and drawbacks.
In fact, first of all, at the end of the forming steps of a tray by bending and folding, a subsequent step of dispensing adhesive material at the above mentioned end flaps is required, said step being followed by a further step of pressing said flaps against the corresponding lateral walls until drying of said adhesive material has been completed.
In addition, trays obtained in accordance with the known art do not lend themselves to be easily dismantled and flattened and subsequently reshaped for a new use because deterioration can take place when the glued end flaps are removed from the lateral wall to which they are fastened. It is to be pointed out in any case that if reshaping of a tray is wished, additional gluing and pressing operations are required to be carried out again to make the engagement between the glued parts steady and obtain a sufficiently strong structure.
Finally, it is to be noted that in trays of known type sometimes structural-yielding problems may occur either if the adhesive material has not been applied in a correct manner and/or in a sufficient amount or if this adhesive material has lost its gluing capacity due to exposure to very high temperatures, for example.
Under this situation the technical task underlying the present invention is to devise a holding tray for foodstuffs and a method of manufacturing said tray that are capable of substantially obviating the mentioned drawbacks.
Within the scope of this technical task it is an important aim of the invention to devise a method of manufacturing holding trays for foodstuffs in which use of adhesive material is avoided, said method being of easy, quick and cheap manufacture.
Another important aim of the invention is to devise a tray that is adapted to be easily dismantled and reduced to a flat sheet without being submitted to any deterioration so that it can be easily and quickly formed again into a tray when required.
It is a further aim to devise a holding tray having a high structural solidity that cannot be altered in time or damaged due to heavy environmental conditions.
The technical task mentioned and the aims specified are substantially achieved by a holding tray for foodstuffs and a method of manufacturing said tray that are characterised in that they comprise one or more of the technical solutions hereinafter claimed.
Description of a preferred but not exclusive embodiment of a holding tray for foodstuffs in accordance with the invention is now given by way of non-limiting example and illustrated in the accompanying drawings, in which:

Fig. 1 is a perspective view of a tray in accordance with a first embodiment of the invention;
Fig. 2 is a top view of the tray shown in Fig. 1 reduced to a portion of flattened laminar material;
Fig. 3 is a perspective view of a second embodiment of the tray in Fig. 1;
Fig. 4 is a top view of the tray in Fig. 3 reduced to a portion of flattened laminar material; and
Fig. 5 is a perspective view of a tray in accordance with a third embodiment of the invention.

With reference to the drawings, the tray in accordance with the invention is generally identified with reference numeral 1.
The tray is formed of a single portion of laminar material susceptible of at least partial permanent deformation, such as thin paperboard for food use, cut out along a contour line 2 and folded according to a plurality of folding lines 3 adapted to define the different parts that will form the tray itself.
More specifically, the folding lines 3 are adapted to define a bottom wall 4 of a substantially rectangular (Figs. 1, 2, 3 and 4) or square (Fig. 5) shape, and at least four lateral walls 5, 6 and as many angular junction regions 7 interposed between said lateral walls 5, 6. Said lateral walls, for obtaining a tray 1 of a flared conformation have a substantially trapezoidal shape the minor base of which is coincident with a respective side of the bottom wall 4 and comprise a first pair of opposite lateral walls 5, preferably the walls corresponding to the minor sides of the bottom wall 4, which in turn have respective end flaps 8 at the upper part that are adapted to be turned over against a predetermined surface 5a of said walls 5. The angular regions 7 consist each of two substantially triangular portions 9 disposed in side by side relationship to be mutually overlapped and to be folded over against the predetermined surface 5a of the adjacent lateral wall 5.
In forming trays 1 the side flaps 8 are designed to overlap corresponding edge bands 7a of the angular regions 7 to block the same against the first pair of opposite lateral walls 5.
In an original manner, said opposite lateral walls and the end flaps 8 have a substantially rounded or convex conformation. In all the illustrated embodiments, the predetermined surface 5a is an outer surface of the first pair of lateral walls 3 and the end flaps 8 have a convexity facing the outside of the tray. This convex conformation causes a steady mating engagement of the end flaps 8 with the outer surface 5a of the corresponding lateral walls 5 and consequently also allows the angular regions 7 to be blocked against said outer surface by the end flaps themselves 8 superimposed thereon. This configuration has been highlighted in Fig. 1 wherein the edge of standard trays has been shown in chain line and the camber defined by the edge 10 in an assembled condition of the tray being the object of the invention relative to the edge of the products presently on the market has been identified as F.
The opposite sides 4a of the bottom wall 4 and the opposite sides 10 of the lateral walls 5, as an alternative to the rectilinear conformation shown in the accompanying figures, can also consist of arched lines, with convexity facing the outside of the tray (in the flat configuration of Figs. 2 and 4), so as to help in determining formation of the rounded configuration of the respective lateral walls 5.
Advantageously, tray 1 may further comprise at least one upper wall 11 formed in the single portion of laminar material as well, the function of which is to close the volume delimited by the lateral walls 5, 6 and bottom wall 4, at the top.
In the embodiment shown in Figs. 3 and 4, tray 1 has a pair of upper closing walls 11, each hinged on one wall of a second pair of opposite lateral walls 6.
Each upper wall 11 has a first pair of sides 12a, 12b one of which 12b is hinged, and a second pair of sides 13 of an arched shape adapted to mate with the opposite sides 10 of the lateral walls 5.
The upper closing walls 11 are movable between an open configuration of tray 1 at which these sides 13 of arched shape of the upper walls 11 are spaced from the opposite sides 10 of the lateral walls 5, and a closed configuration of said tray at which the sides 13 of arched shape of the upper walls 11 are disposed close to the opposite sides 10 of the lateral walls 5. Both configurations are shown in Fig. 3.
In order to retain the upper walls 11 in the closed configuration, tray 1 has a pair of flaps 14 each formed in a respective lateral wall 5 belonging to said first pair 5. As shown in Fig. 4, each flap 14 is obtained through a U-shaped cut formed close to the opposite sides 10 of the lateral walls 5. The flap 14 is subsequently folded so that it is disposed transversely of the lateral walls 5.
Finally, in accordance with a further embodiment of the invention, the four lateral walls 5, 6 all have a substantially rounded conformation the convexity of which faces the outside of tray 1, to preferably delimit a substantially circular upper edge 15 (Fig. 5) .
The invention carries out a new method that is an integral part of the present patent as well.
In accordance with said method, with reference to the first embodiment shown in Figs. 1 and 2, it is provided a step of cutting out, along a contour line 2, a single portion of laminar material that can be susceptible of at least partial permanent deformation, consisting of thin paperboard for food use for example, and a step of folding said portion of laminar material along lines adapted to form the tray by defining the above described parts, i.e. a bottom wall 4, four opposite lateral walls 5, 6, two end flaps 8 and four angular regions 7.
In an original manner, at the end of the known folding and tray-formation steps involving superposition of the end flaps 8 turned over towards the outer surface 5a of walls 5, on the edge bands 7a of the angular regions 7 in turn folded up (with the two triangular portions 9 constituting each of them) against the outer surface 5a itself, the method in accordance with the invention comprises a single final operating step consisting in submitting at least said opposite lateral walls 5 and the respective end flaps 8 to a deforming action giving them a curved shape the convexity of which faces the outside of the tray, which deforming action is by itself able to cause a steady mating engagement of said end flaps 8 with the outer surface 5a of the corresponding lateral walls 5.
The invention achieves important advantages.
In fact, first of all, the method in accordance with the invention enables achievement of solid holding trays for food without providing use of adhesive material or in any case limiting said use to minimum amounts for possibly making the tray structure more solid and strong.
The possibility of avoiding the gluing step makes the manufacturing method of the trays in accordance with the invention quicker, of easier accomplishment and reduced costs.
It will be also appreciated that the trays in accordance with the invention can be easily dismantled to be reduced to a flat sheet since no separation between glued portions is required. In addition, also reconstruction of a tray for reuse can be easily and quickly obtained because it is sufficient to manually restore the convex shape of the lateral walls to which a curved conformation had been already given.
Finally, it will be recognised that the trays in accordance with the invention are very solid and reliable because their structural steadiness exclusively results from the permanent deformation of the paper material of which said trays are made and is not due to the presence of the adhesive material that is always subject to possible deterioration.

Claims

A holding tray for foodstuffs of the type consisting of a single portion of laminar material susceptible of at least partial permanent deformation which is cut out along a contour line (2) and folded along folding lines (3) adapted to define a bottom wall (4), at least four lateral walls (5, 6) comprising a first pair of opposite lateral walls (5) having respective end flaps (8) at the top which are adapted to be turned over against a predetermined surface (5a) of said walls (5), and at least four angular junction regions (7) interposed between said lateral walls (5, 6) and to be folded down against the predetermined surface (5a) of an adjacent lateral wall (5) belonging to said first pair, the end flaps (8) being designed to overlap corresponding edge bands (7a) of said angular regions (7) to block them against said first pair of opposite lateral walls (5),
characterised in that said first pair of opposite lateral walls (5) and the respective end flaps (8) have a substantially rounded or convex conformation adapted to give rise to a steady mating engagement of said end flaps (8) with the predetermined surface (5a) of the corresponding lateral walls (5).
A tray as claimed in claim 1, characterised in that the predetermined surface (5a) is an outer surface of the first pair of lateral walls (5), and in that the end flaps (8) have a convexity facing the outside of the tray (1).
A tray as claimed in claim 1, characterised in that said material susceptible of at least partial permanent deformation consists of thin paperboard for food use.
A tray as claimed in claim 1, 2 or 3, characterised in that said bottom wall (4) has a substantially rectangular shape.
A tray as claimed in claim 1, 2 or 3, characterised in that said bottom wall (4) has a substantially square shape.
A tray as claimed in claim 4 or 5, characterised in that said bottom wall (4) at the first pair of opposite lateral walls (5) has substantially rectilinear opposite sides (4a) and/or opposite sides (10).
A tray as claimed in claim 4 or 5, characterised in that said bottom wall (4) at said first pair of opposite lateral walls (5) has arched opposite sides (4a) and/or opposite sides (10) with convexity facing the outside of the bottom wall (4) when developed in the tray plane.
A tray as claimed in claim 1, characterised in that it further comprises at least one upper wall (11) formed in the single portion of laminar material and designed to close the tray (1).
A tray as claimed in claim 4 or 5, characterised in that it further comprises a pair of upper closing walls (11), each formed in the single portion of laminar material and hinged on a lateral wall (6) of a second pair of opposite lateral walls (6).
A tray as claimed in claim 9, characterised in that it further comprises a pair of flaps (14) to retain the upper closing walls (11) in a closed configuration of the tray (1).
A tray as claimed in claim 10, characterised in that each flap (14) is formed in a respective lateral wall (5) belonging to said first pair (5).
A tray as claimed in claim 1, characterised in that all said at least four lateral walls (5, 6) have a substantially convex conformation with convexity facing the outside of the tray (1).
A tray as claimed in claim 12, characterised in that the lateral walls (5, 6) with a substantially convex conformation delimit a substantially circular upper edge.
A tray as claimed in claim 1, characterised in that the four angular junction regions each consist of two substantially triangular portions (9) disposed in side by side relationship to be mutually overlapped.
A method of manufacturing a holding tray for foodstuffs, comprising the steps of:

cutting out, along a contour line (2), a single portion of laminar material that is susceptible of at least partial permanent deformation,

and folding said portion of laminar material along folding lines (3) adapted to form the tray itself by defining a bottom wall (4), at least four lateral walls (5, 6) comprising a first pair of opposite lateral walls (5) and having respective end flaps (8) at the top which are adapted to be turned over against the outer surface (5a) of said walls (5), and at least four angular junction regions (7) interposed between said lateral walls (5, 6), to be folded over against the outer surface (5a) of an adjacent wall (5) belonging to said first pair, the end flaps (8) being designed to overlap corresponding edge bands (7a) of said angular regions (7) to block them against said first pair of lateral walls (5),

characterised by submitting at least said first pair of opposite lateral walls (5) and the respective turned over end flaps (8) to an operating step of deformation according to a curved shape with convexity towards the outside of the tray, which is adapted to give rise to a steady mating engagement of said end flaps (8) with the outer surface (5a) of the corresponding lateral walls (5).