EP3046846B1 - Blank of sheet material having centring tabs, box and method implementing such a blank - Google Patents

Description

The present invention relates to a blank of cardboard or corrugated cardboard comprising a series of four parts connected together in pairs by fold lines and having on each side a set of rectangular flaps.

It also relates to a box obtained with such a blank and a method of producing such a box.

It finds a particularly important application although not exclusive in the field of pallet stackable boxes of light material (<450 g / m ² ) for example used to transport packets of cereals that occupy the entire volume of the box, thus realizing a part of the compressive strength of the assembly, or for freezer bags whose weight per bag is limited.

Such packages must on the one hand resist compression during stacking, and on the other hand do not slip relative to each other during transport in a truck or trolley.

Box centering systems are already known by lateral tenons cooperating with orifices placed on the edges of the packages. Such means are fragile and can not be put in place when the lower and upper surfaces of the body are smooth by construction as in the case of so-called "wrap" packaging.

Locking / locking systems are also known by tongues glued to the upper face of a cover which it passes through ( FR 2,761,341 ). Other systems are known documents JP H10 81334 and US 4,053,098 . Such systems implement two separate blanks, one for the box and the other for its cover, the establishment of the latter requiring a precise adjustment, difficult to achieve automatically.

The present invention aims to provide a blank, a box and a method of forming a box that responds better than those previously known to the requirements of practice, in particular in that it causes a centering of the boxes formed from a blank in one piece, making it possible to stack the boxes one on the other with excellent self-locking and vertical alignment of the boxes with respect to one another perfectly, while providing an upper face of the cap of the box and a bottom face of the bottom of the box smooth design.

With the invention it is thus possible to form the box easily automatically around the products themselves, as is the case wrap packaging, but also around a mandrel, (the box is then filled by the side), and this while allowing excellent results of later centering, during the constitution of stack, and compressive strength.

For this purpose, the invention notably proposes a blank of cardboard or corrugated cardboard comprising a succession of four shutters connected together in pairs by first fold lines, namely two shutters. end members separated by two intermediate flaps and having on either side a set of rectangular flaps, characterized in that an intermediate flap comprises at least one recess adjacent to a first fold line joining an end flap, said end flap having on its peripheral edge opposite said first fold line, a tongue of complementary shape to the recess directly above said recess and connected to said shutter by a second folding line parallel to the first folding lines .

By plumb, is meant on the same longitudinal longitudinal line parallel to the longitudinal axis of the blank.

Note that this tongue of complementary shape is intended to also serve as a bonding tongue with the other end flap during forming of the box.

Thus, with the same tongue and unexpectedly, two functions in one during the forming of the box, namely a centering function and a function of fixing an end flap on the other.

• le volet intermédiaire comporte deux évidements adjacents à la dite première ligne de pliage et ledit volet d'extrémité comprend deux languettes correspondantes. Avantageusement les languettes sont symétriques par rapport à l'axe central longitudinal du flan.

In advantageous embodiments, one and / or the other of the following provisions is also used:

• the intermediate flap comprises two recesses adjacent to said first fold line and said end flap comprises two corresponding tabs. Advantageously, the tongues are symmetrical with respect to the longitudinal central axis of the blank.

Also advantageously the cumulative average width in the transverse direction of the tongues is greater than 1/4 of the width of the flaps in the transverse direction, for example greater than 1/3 or greater than or equal to half of said width, and / or lower at 3/5 of this one.

• les languettes sont formées chacune par une portion de carton rectangulaire ou trapézoïdale ;
• l'évidement est en partie à cheval sur la première ligne de pliage et comprend un bord découpé disposé parallèlement et à une distance déterminée d avec laite première ligne de pliage (dont il est adjacent);
• d est compris entre une et deux épaisseurs de carton.

Mean width means the average between the smallest width and the largest width of the tongue;
Also advantageously three or four tabs are provided symmetrically with respect to the longitudinal axis;

• the tongues are each formed by a rectangular or trapezoidal portion of cardboard;
• the recess is partly straddling the first fold line and comprises a cut edge disposed parallel and at a determined distance d with said first fold line (of which it is adjacent);
• d is between one and two layers of cardboard.

The invention also proposes a box of cardboard or corrugated cardboard obtained from a blank as described above.

It also relates to a cardboard box or corrugated cardboard, formed from a blank comprising a series of four parts interconnected by first fold lines, two of the shutters forming the bottom and the cap of the box and the other two forming two first side walls facing each other, said series being provided on one side with a first set of flaps and on the other side with a second set of flaps, said sets forming the other two walls adjacent to the first walls opposite, characterized in that the shutter forming the bottom comprises at least one recess adjacent to a first fold line and in that the shutter forming the cap comprises at least one tongue connected to the adjacent wall by a second fold line, glued to said cap in line with the recess and of complementary shape to said recess.

In an advantageous embodiment, the cumulative average width in the transverse direction of the tongue or tongues is greater than 1/3 of the width of the end flap and less than 3/5 of said width.

Advantageously, the bottom has two recesses adjacent to said first fold line and the cap comprises two corresponding tongues.

In an advantageous embodiment the tabs are each formed by a rectangular or trapezoidal cardboard portion.

Also advantageously the obvious is partially straddling the first fold line corresponding.

The invention also proposes a method for producing a packaging box from a blank as described above, in which, after unstacking the blank from a store, the blank is automatically wrapped around products to be wrapped or around a mandrel by folding the tabs previously glued around the peripheral edge of the end flap to which they are connected, which is pressed against the corresponding upper face of the adjacent end flap to stick them on this, and is formed simultaneously or substantially simultaneously by folding around the end face of the products or mandrel, one set of flaps to form one of the walls of the box before final closure of the latter by the another set of flaps or ejection of the latter thus formed for subsequent filling with the products.

• La figure 1 est une vue en plan d'un mode de réalisation d'un flan selon l'invention.
• La figure 2 est une vue en perspective de deux boîtes partiellement empilées l'une sur l'autre obtenue avec des flans selon la figure 1, mettant en évidence le centrage obtenu.

The invention will be better understood on reading the following description of an embodiment given below by way of non-limiting example. It refers to the accompanying drawings in which:

• The figure 1 is a plan view of an embodiment of a blank according to the invention.
• The figure 2 is a perspective view of two boxes partially stacked one on the other obtained with blanks according to the figure 1 , highlighting the centering obtained.

The figure 1 shows a blank 1 of corrugated cardboard, for example double-sided, with a thickness of 2 to 3 mm.

It comprises a suite 2 of four shutters 3, 4, 5, 6 separated between them two by two by first parallel fold lines 7, 8, 9, namely two rectangular end flaps 3 and 6 and two intermediate rectangular flaps 4 and 5, the flaps 3 and 5 on the one hand, and 4 and 6 on the other hand being of identical or substantially identical dimensions.

The following 2 comprises on each side a first set 10 and a second set 11 of rectangular flaps connected to the lateral ends of the flaps by junction lines 12 and 13 perpendicular to the first fold lines.

The flaps of the game 10 are sized to allow forming a side wall of the closed body, while the flaps of the game 11 are arranged to leave an opening (cf. figure 2 ) to see the products inside, in a manner known in itself.

The intermediate flap 5 intended to form the bottom of the box, comprises two identical recesses 13, isosceles trapezoidal shape adjacent to the fold line 9, the end edge 14 of the recess (slightly straddling the fold line 9) forming the small base of the trapezium and being at a distance d , on the side of the end flap 6, equal to the thickness of the carton, for example here 3 mm.

The adjacent end flap 6 which will form a wall of the box has on its peripheral edge 15, opposite the fold line 9, two tabs 16 of trapezoidal shape isosceles complementary to that of the recesses 13, located plumb. (alignment corresponding to the mixed line 17) of the recesses and connected to the flap 6 by second fold lines 8 parallel to the first fold line 9.

The dimensions of the recesses 13 and tabs 16 are arranged to allow a good fit into each other, for example by dimensioning the tabs a little smaller (-0.5 mm in dimensions) than the recesses. The tongues 16 are moreover of dimensions in width (in the transverse direction of the blank) and in length (in the longitudinal direction of the blank) to allow a solid and sufficient fixation by gluing on the other end flap 3.

More precisely, the length l ₀ (in the longitudinal direction of the sequence of flaps) of the recesses 13 and / or the tongues 16 is less than 1/3 of the length l of the intermediate flap, for example less than 1/4, for example 1/5 of this width, to avoid embrittlement of the bottom (but at least greater than 1/8 l ).

The average width L ₀ of the tabs 16 (in the transverse direction of the blank) and / or the recesses 13 is arranged, to accumulate the widths of the tongues (here two in number) have a good fastening flaps end of them, for example a cumulative width of the order of 1/3 of the transverse length of the flap, but may be between 1/4 and 1/2, so as not to weaken the bottom either.

The tabs are thus and for example, in the mode described more particularly here, each with a large end base equal to 1/4 and a small end base equal to 18% of the total width L.

We have shown on the figure 2 a stack in progress of two boxes 19 and 19 'obtained with the blank 1 of the figure 2 .

The recesses 13 of the top box 19 cooperate with the tabs 16 'of the lower box 19', the latter having been folded and glued to the upper face 20 'of the corresponding flap 3'.

The centralizers thus obtained guarantee the perfect positioning of the dihedrons formed by the tongues, on the dihedrons formed by the recesses, and thus the alignment of the faces allowing thus strengthen the vertical strength of the stack and reduce the weight of the board.

We will now describe the manufacture of a box 19 from a blank 1 according to the embodiment of the invention more particularly described here.

A device comprising gripping means suction cuts, gluing means and product positioning means at a forming station or a coating mandrel of the known type, for example, will be used to be done.

After unstacking a blank from a store for example vertical, by suction, it comes to stick the inner face of the tabs 16 which will both serve as a centralizer and means for fixing the end flaps between them to the place gluing tabs conventionally used in blanks known as wrap.

Then the blank is placed around a mandrel or around the products to be packaged, and it is coated by coming to press the tabs 16 on the upper face of the flap 3 around the fold lines 18 and the end edge 21 of the flap 3, so as to form the centerers which will come opposite the recesses of the box above.

As is obvious and as also follows from the above, the present invention is not limited to the embodiments more particularly described. On the contrary, it embraces all the variants and in particular those where the tongues have a rounded shape, a T shape, a rectangle trapezoid shape, those where the flaps are arranged to form a perforated wall of the two sides, one where there is only one tab centered, three or four tabs centered, symmetrical with respect to the longitudinal axis of the blank to allow a good distribution.

Claims (11)

1. Cardboard or corrugated cardboard blank (1) including a series of four flaps (3, 4, 5, 6) joined together in pairs by first fold-lines (7, 8, 9), namely two end flaps (3, 6), separated by two intermediate flaps (4, 5) and including on each side a set of rectangular tabs (10, 11), characterised in that an intermediate flap (5) comprises at least one opening (13) adjacent to a first joining fold-line (9) to an end flap (6), said end flap (6) including along its peripheral edge opposite to said first fold-line (9), at least one tongue (16) of complementary shape to the opening (13) situated in line (17) with said opening and joined to said flap by a second fold-line (18) parallel with the first fold lines.
2. Blank according to claim 1, characterised in that said intermediate flap includes two openings (13) adjacent to said first fold-line (9) and said end flap comprises two corresponding tongues (16).
3. Blank according to any one of the preceding claims, characterised in that the tongues are each formed by a rectangular or trapezoidal portion of cardboard.
4. Blank according to any one of the preceding claims, characterised in that the cumulative average width of the tongues in the transversal direction of the blank is greater than 1/3 of the width L of the flaps in the transversal direction, and less than 3/5 of said width L.
5. Blank according to any one of the preceding claims, characterised in that the opening partially straddling the fold-line (9), comprises a cut edge (14) arranged parallel with and at a determined distance d from the first fold-line (9) to which it is adjacent.
6. Blank according to claim 5, characterised in that d is between one and two thicknesses of cardboard.
7. Box (19, 19') made of cardboard or corrugated cardboard, formed from a blank (1) comprising a series (2) of four flaps (3, 4, 5, 6) joined together by first fold-lines (7, 8, 9), two of the flaps forming the base and the lid of the box and the other two forming two first facing lateral walls, said series being provided on one side with a first set of tabs (10) and on the other side with a second set of tabs (11), said sets forming the two other lateral walls adjacent to the first facing walls, characterised in that the flap forming the base (5) comprises at least one opening (13) adjacent to a first fold-line (9), and in that the flap forming the lid comprises at least one tongue (16) joined to the adjacent wall (6) by a second fold-line (18), glued onto said lid in line with the opening and of complementary shape to said opening.
8. Box according to claim 7, characterised in that the base includes two openings (13) adjacent to said first fold-line (9) and the lid comprises two corresponding tongues (16).
9. Box according to any one of claims 7 and 8, characterised in that the tongues (16) are each formed by a rectangular or trapezoidal portion of cardboard.
10. Box according to any one of claims 7 to 9, characterised in that the opening partially straddles the first fold-line.
11. Process for forming a packaging box from at least one blank made of cardboard or corrugated cardboard material, according to any one of claims 1 to 7, characterised in that after removal of the blank (1) from a magazine, the blank is automatically wrapped around the goods to be packaged or around a mandrel folding the previously glued tongues (16) around the peripheral edge of the end flap (6) to which they are joined, in that they are pressed against the corresponding upper face of the adjacent end flap (3) to glue them to this, and simultaneously or substantially simultaneously one of the sets of tabs is assembled, by folding around the end face of the goods or of the mandrel, to form one of the walls of the box before final closure of the latter by the other set of tabs or ejection of the latter thus assembled for subsequent filling with the goods.

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