EP2035288B1 - Plastic bag with gussets for food products and its method of manufacture - Google Patents

Abstract

The bag has gussets (1a, 1b) formed at a level of longitudinal edges of the bag and resulting from two inner folds (a, b) formed from a median line (c), where the bag is made of plastic material. The folds connect a front side (1c) and a rear side (1d) of the bag by connecting zones (d, e). The gusset (1b) presents an arrangement acting as a gripping handle. The arrangement is formed at a level of the folds of the gusset (1b) by combining with a connected element, which is fixed between the connecting zones. An independent claim is also included for a method of fabricating a gusseted bag made of plastic material.

Description

The invention relates to the technical sector of plastic packaging bags, in particular of the type intended to receive animal feed, in the form of granules for example.

The invention relates to a gusseted bag according to the preamble of claim 1 and to a method of manufacturing a plastic bellows bag according to claim 1.

Generally, these types of bags have, in a manner perfectly known to a person skilled in the art, bellows capable in particular of increasing the capacity of the bag. These bellows are formed at the longitudinal edges of the bag, between two walls constituting the front face and the rear face of the bag. These bellows are made, most often, over the entire height of the bag.

Various technical solutions can be used to carry out, continuously, this type of bags. For example, in an advantageous manner, the bags are made from a roll of a plastic film which is unrolled continuously. For example, the plastic film is subjected to operations to delimit, between its two longitudinal edges, a portion intended to constitute the front face of the bag, a portion intended to constitute one of the bellows, a portion intended to constitute the back side of the bag and a portion intended to constitute the other bellows. The film is then subjected to various successive bending, cutting and welding operations, to produce a bellows bag with a bottom and generally a filling opening.

Moreover, whatever the embodiment, the upper portion of the bag, opposite the bottom, usually has, above a sealed closure zone, arrangements constituting a gripping handle.

Since these bags have a height much greater than the width, difficulties may arise to lift and carry the bag. Indeed, the handle, especially in the case of large bags, is located at such a distance from the ground, it is necessary, especially for a person of small size, to make significant efforts, in order to ability to lift and take off the bottom of the bag from the ground.

In an attempt to overcome these drawbacks, it has been proposed to have arrangements that act as a gripping handle, no longer at the level of the upper horizontal edge of the bag, but substantially at the median portion of one of the bellows edges of the bag. bag, so that it can be transported horizontally and not vertically. Such positioning of the handle allows the wearer to orient the bag with its largest dimension (which corresponds to its height) in the horizontal direction thus reducing the vertical size of the bag, which requires a much less important effort to lift it off the ground.

Various technical solutions have been proposed to achieve this function.

For example, a solution emerges from the teaching of the patent FR 2,791,040 which the applicant of this is also the holder.

According to the teaching of this patent, a handle, disposed substantially at half a length of one of the longitudinal edges bellows of the bag, is constituted by a strip of heat-sealable material on the bag. The length of the band is equal to the developed transverse length of the bellows increased by the length of two extreme returns fixed by welding on the corresponding outer edges of the bellows considered. This solution requires the use of materials based on heat-sealable plastic, to allow the attachment of the handle in the form of added handle.

Another solution emerges from the teaching of the document WO / 02/074646 , according to which a handle is made from an opening formed in a part which extends each of the folds of one of the bellows. Concretely, one of the bellows of the bag has folds of length at least twice the length of the folds of the other bellows. A weld line formed at a determined distance from the fold of the two folds of great length makes it possible to produce identical bellows on each side, one of which has, in all of its length, a free band in which can be formed the grip handle. This embodiment therefore increases, in a useless manner, the width of the container bag considered and obviously requires an excess material significantly increasing the manufacturing costs. A bellows bag according to the preamble of claim 1 is known from the document US-A1-5186 542 .

The object of the invention is to remedy these disadvantages in a simple, safe, effective and rational manner.

The problem to be solved by the invention is to be able to make a grip handle at the longitudinal bellows of a plastic bag, in particular with an outer layer of PET, from a conventional manufacturing process bags continuous, and whose bellows are the same size on each side, with the constraint of maintaining a seal inside the bag. Remember that the PET does not allow to perform a weld.

To solve such a problem, it has been designed and developed a bellows plastic bag for food products, the bellows being formed at the longitudinal edges of the bag and resulting from two internal folds formed from a median line and connecting, by connecting areas, the front face and the rear face of said bag. At least one of said bellows has arrangements acting as a handle.

According to the invention, the arrangements consist of openings formed in the thickness of the folds of the bellows, facing an insert which is fixed inside the folds of the bellows sealingly.

Given these characteristics, it therefore appears that the arrangements acting as a handle, are formed within the area defined by the folds of the bellows.

From this design, various embodiments can be provided to achieve the arrangements acting handles handles.

In a first embodiment, the arrangements consist of openings formed in the thickness of the folds of the bellows, substantially in the middle of the length of said bellows and facing the insert which is fixed inside the folds of the bellows, in a sealed manner. The openings are of substantially oblong general shape and are arranged symmetrically, on either side of the median line of the two folds, delimiting a central band which constitutes the handle as such, after having introduced a hand through said openings .

In this embodiment, to solve the problem posed to facilitate the formation of the handle, profiled slots may be formed transversely in the thickness of the folds of the bellows, opposite the insert, and on both sides openings.

In another embodiment, the arrangements consist of profiled slots formed in the thickness of the folds of the bellows, facing the insert which is fixed inside the folds of the bellows, in a sealed manner, said slots being arranged symmetrically, on either side of the median line of the two folds, delimiting a central strip which constitutes the handle as such after having introduced a hand through said slots.

In these two embodiments, it appears that the handle as such is made directly from the material constituting the bag.

In order to reinforce the handle thus formed, provision is made to bring back and fix inside the folds of the bellows, a reinforcement strip located opposite the sealing ratio element, the openings and / or slots being formed also in the thickness of this band.

In another embodiment, the arrangements are constituted by slots or openings formed in the thickness of the insert which is attached to the outside of the folds of the bellows substantially in the middle of the length of said bellows. The slots or openings are formed symmetrically on either side of the center line of the insert by delimiting a central strip which constitutes the handle as such, after having introduced a hand through said slots or openings.

In this other embodiment, to allow the insert to form the handle as such, this insert is fixed at its longitudinal edges only, near the connection areas of the folds of the bellows with the front faces. and back.

Whatever the embodiment considered, the insert has a substantially quadrangular planar shape.

More particularly, when the handle is made from openings or slots formed in the folds of the bellows considered, the insert has a substantially quadrangular planar shape sized to completely cover the openings or slots to create a seal inside the bag.

The invention also relates to a method of manufacturing a plastic bellows bag according to claim 1.

• on déroule, en continu, un rouleau d'un film de matière plastique que l'on soumet à des opérations pour délimiter, entre les deux bords longitudinaux du film, une partie constituant la face avant du sac, une partie constituant l'un des soufflets, une partie constituant la face arrière du sac, une autre partie constituant l'autre soufflet ;
• on soumet en continu, à intervalles réguliers, l'une des parties constituant l'un des soufflets à au moins une opération apte à constituer des agencements faisant office de poignée ;
• on soumet le film à différentes opérations de pliage, de coupe et de soudure, pour réaliser un sac présentant un fond, des bords longitudinaux à soufflets et une ouverture.

According to the invention, the method comprises the following essential steps:

• a roll of a film of plastic material is unrolled continuously and subjected to operations for delimiting, between the two longitudinal edges of the film, a part constituting the front face of the bag, a part constituting one of the bellows, a portion constituting the rear face of the bag, another portion constituting the other bellows;
• continuously subject, at regular intervals, one of the parts constituting one of the bellows to at least one operation adapted to constitute arrangements acting as a handle;
• the film is subjected to various folding, cutting and welding operations to produce a bag having a bottom, longitudinal gusseted edges and an opening.

• la figure 1 est une vue en perspective d'un sac à soufflets selon l'état antérieur de la technique, c'est-à-dire avec une poignée de préhension formée au niveau du bord supérieur du sac ;
• la figure 2 est une vue en perspective d'un sac identique à celui de la figure 1, mais dont l'un des bords longitudinal à soufflet est agencé selon l'invention pour constituer une poignée de préhension ;
• la figure 3 est une vue de face, à caractère schématique, du sac selon l'invention ;
• la figure 4 est une vue en coupe transversale considérée selon la ligne 4-4 de la figure 3 ;
• les figures 5, 6, 7 et 8 sont des vues en plan montrant une partie du procédé de fabrication du sac à partir d'un film continu de matière plastique pour la réalisation des agencements faisant office de poignée de préhension au niveau de la partie du film destiné à constituer l'un des soufflets, ces figures montrant différentes formes de réalisation des agencements, pour constituer la poignée de préhension ;
• la figure 9 est une vue en coupe transversale considérée selon la ligne 9-9 de la figure 5, les épaisseurs ayant été volontairement exagérées, pour une meilleure compréhension des dessins ;
• la figure 10 est une vue semblable à la figure 9 montrant la formation de la poignée ;
• la figure 11 est une vue en coupe transversale considérée selon la ligne 11-11 de la figure 8, les épaisseurs ayant été volontairement exagérées ;
• les figures 12 et 13 sont des vues semblables aux figures 9 et 10 d'une forme de réalisation avec adjonction d'une bande de renfort au niveau de la poignée.

The invention is described below in more detail with reference to the figures of the accompanying drawings, in which:

• the figure 1 is a perspective view of a bellows bag according to the prior art, that is to say with a gripping handle formed at the upper edge of the bag;
• the figure 2 is a perspective view of a bag identical to that of the figure 1 but one of the longitudinal edges bellows is arranged according to the invention to form a handle gripping;
• the figure 3 is a schematic front view of the bag according to the invention;
• the figure 4 is a cross-sectional view taken along line 4-4 of the figure 3 ;
• the figures 5 , 6 , 7 and 8 are plan views showing a part of the bag manufacturing process from a continuous film of plastic material for making arrangements as a grip handle at the portion of the film intended to constitute one of the bellows these figures showing different embodiments of the arrangements, to form the handle;
• the figure 9 is a cross-sectional view taken along line 9-9 of the figure 5 , the thicknesses having been voluntarily exaggerated, for a better understanding of the drawings;
• the figure 10 is a view similar to the figure 9 showing the formation of the handle;
• the figure 11 is a cross-sectional view taken along line 11-11 of the figure 8 thicknesses having been deliberately exaggerated;
• the Figures 12 and 13 are views similar to Figures 9 and 10 of an embodiment with the addition of a reinforcing strip at the handle.

As indicated, in a manner perfectly known to those skilled in the art, the bellows bag according to the invention is obtained from a plastic film (1) which is subjected to successive bending operations to achieve longitudinal bellows (1a) and (1b) between two walls (1c) and (1d) constituting the front and rear faces of the bag. These arrangements are well known to those skilled in the art and are not described in detail. It is the same with regard to the realization of a bottom (1e) which can result from a joint by welding, at the lower end of the two walls (1c) and (1d) and a drawdown on the one of the walls (1c) or (1d).

It is also recalled, in a known manner, that each bellows (1a) and (1b) results from two internal folds (a) and (b) formed from a median line (c). The folds (a) and (b) connect, by connecting zones (d) and (e), the front face (1c) and the rear face (1d) of the bag. It should be noted that a weld line can be made at connection zones (d) and (e) in order to form the folds as such ( Figures 3 and 4 ).

According to the invention, the two internal pleats (a) and (b) of at least one of the bellows (1b) have arrangements capable of forming, in combination with an insert (2), at least a handful of grasping (P). As will be indicated in the following description, the insert (2) is fixed between the connection zones (d) and (e).

The insert (2) has a planar shape, substantially quadrangular. This element (2) can be made of the same material as that constituting the bag or in another material, with the only constraint of being able to weld this element at the time of continuous manufacture of the bag, as will be indicated in the following the description.

In the embodiment illustrated at Figures 5, 9 and 10 , the arrangements are constituted by openings (01) and (02) formed in the thickness of the folds (a) and (b) of the bellows (1b).

In order to maintain the tightness inside the bag, the insert (2) is fixed on its four sides on the inner side of the part of the film (1) intended to form the bellows (1b). The element (2) is sized to completely cover the openings (02) and (01). For example, the fixing of four sides of the element (2) is made by welding, the lateral edges of the element (2) being welded at the welds of the connection zones (d) and (e).

The openings (01) and (02) are of generally substantially oblong shape and arranged symmetrically on either side of the center line (c) of the two folds (a) and (b). These two openings (01) and (02) therefore delimit a central band which constitutes the handle as such (P), after having introduced at least one hand through said openings ( Figures 9 and 10 ).

From this conception illustrated to Figures 5, 9 and 10 , and to facilitate the formation of the handle (P), slots (F) may be formed transversely in the thickness of the folds (a) and (b) of the bellows (1b). These slots (F) are formed opposite the attached sealing element (2) and on both sides of the openings (01) and (02) ( figure 6 ).

In the illustrated embodiment figure 7 , the arrangements consist of substantially omega (F1) and (F2) profiled slots formed in the thickness of the folds (a) and (b) of the bellows (1b), opposite the sealing insert ( 2). These profiled slots (F1) and (F2) are formed symmetrically, on either side of the median line (c) of the two folds (a) and (b), delimiting, as before, a central band which constitutes the handle as such (P), after having introduced a hand through said slots.

In the embodiments described above, the handle as such (P) resulting from the openings and / or slots, in combination with the sealing insert (2), is formed directly from the material constituting the bag.

Importantly, in these embodiments, it is intended to fix, in the area of the bellows where will be formed the arrangements as a handle, a reinforcing strip (3). As indicated above, the sealing insert (2) is fixed opposite this reinforcing strip (3) which has, in the same way as the folds of the bellows, openings (3a) and (3b) and / or slots.

In the embodiment illustrated at Figures 8 and 11 , the sealing insert (2) is fixed not on the inside, but on the outside of the folds (a) and (b). In this embodiment, the element (2) has slots or openings (2a) and (2b) formed symmetrically and on either side of its median line. These slots or openings (2a) and (2b) define a central strip (2c) which constitutes the handle (P) as such, after having introduced a hand through said slots or openings.
In this embodiment, the insert (2) is fixed only at its longitudinal edges (2d) near the connection areas (d) and (e).
Note that, in this embodiment, the element (2) does not participate directly in maintaining the seal inside the bag, since the openings or slots (2a) and (2b) for the passage of the hand, are formed directly in said element (2) and no longer in the thickness of the folds (a) and (b) of the bellows (1b).

By considering these different embodiments, to constitute arrangements acting as a handle, substantially in the part median of at least one of the bellows of the bag, always having the objective of maintaining a perfect seal inside the bag, these different arrangements can be executed at the time of the continuous realization of the bag and before the formation as than such of the latter.

The invention also relates to the method of manufacturing a gusseted plastic bag according to claim 1.

As shown in particular by figures 5 , 6 , 7 and 8 , the different bellows bags are obtained from a roll of a film (f) of plastic material which is unwound continuously, or (A) the unwinding direction of the film (f). This film (f) is, in a manner perfectly known to a person skilled in the art, subjected to various operations to delimit, between its two longitudinal edges (f1) and (f2), a portion constituting the front face (1c) of the bag , a portion constituting one of the bellows (1b), a portion constituting the rear face (1d) of the bag and another portion constituting the other bellows (1a).

In the illustrated example, the portion constituting the bellows (1b) is continuously subjected, at regular intervals, to at least one operation capable of constituting the arrangements serving as a handle.
For example, if we consider the previously described embodiments, in the part (1b), the openings (01) and (02) are made with, optionally, the slots (F) (or the slots (F1 )), then, in a second step, is reported and fixed, under the conditions indicated above, that is to say on the side of the film intended to constitute the inside of the film, the element (2) to cover all the openings or slots to create the seal inside the bag, after formation of the latter.

It is recalled that prior to the introduction of the sealing element (2), the region of the bellows where the arrangements acting as gripping handles must be formed, can advantageously be equipped with a reinforcing strip (3). . In this case, the openings and / or slots are also formed in the thickness of this strip (3).

In the illustrated embodiment figure 8 , on the side of the film intended to constitute the outside of the bag, is attached and fixed on substantially the width of the portion (1b), the element (2) having the openings or slots (2a) and (2b).

The film is then subjected to various cutting, welding and folding operations, in order to produce, in a manner perfectly known to those skilled in the art, a bag having a bottom, bellows and an opening.

It is also recalled that after filling, for example, the bag is generally closed, in a sealed manner, at its horizontal upper edge. Similarly, one of the walls, the face (1c) for example, can be equipped with a system of opening and closing at will, type "ZIP®" closure "ECLAIR®" ....

• la formation d'agencements faisant office de poignée, directement dans au moins l'un des soufflets qui constituent les bords longitudinaux du sac, tout en respectant l'étanchéité à l'intérieur du sac, et sans être obligé de prolonger la hauteur du soufflet considéré pour former la poignée ;
• la réalisation en continu des agencements au moment de 1a formation du sac sur une chaîne automatique et non pas après formation du sac en tant que tel ;
• la facilité de réalisation ;
• l'esthétique ;
• en position pliée de stockage, ou de remplissage, les agencements faisant office de poignée, ne débordent pas du sac en étant totalement intégrés dans la largeur du soufflet.

The advantages stand out well from the description, in particular one underlines and recalls:

• the formation of arrangements acting as a handle, directly in at least one of the bellows constituting the longitudinal edges of the bag, while respecting the tightness inside the bag, and without having to extend the height of the bellows considered to form the handle;
• the continuous production of the arrangements at the time of the formation of the bag on an automatic chain and not after formation of the bag as such;
• ease of realization;
• aesthetics;
• in the folded storage or filling position, the arrangements acting as a handle, do not overflow the bag being fully integrated into the width of the bellows.

Of course, without departing from the scope of the invention, it is not excluded to always arrange the upper part of the bag with means acting as a handle.

Claims (13)

1. Plastic bag with gussets (1a) and (1b) for food products, the gussets (1a) and (1b) being formed on the lengthwise sides of the bag and resulting from two internal folds (a) and (b) made from a median line (c) and joining, via connecting zones (d) and (e), the front face (1c) and the back face (1d) of the said bag, at least one of the said gussets (1b) having arrangements acting as a handle, characterized in that the arrangements consist of openings (O1) and (O2) made in the thickness of the folds (a) and (b) of the gusset (1b), facing an added element (2) which is fastened to the inside of the folds (a) and (b) of the gusset, in a sealed manner.
2. Bag according to Claim 1, characterized in that the openings (O1) and (O2) are made substantially at the middle of the length of the gusset, facing the added element (2) which is fastened between the connecting zones of the internal folds (a) and (b) of the gusset with the front (1c) and back (1d) faces.
3. Bag according to Claim 1, characterized in that the openings (O1) and (O2) are made in the thickness of the folds (a) and (b) of the gusset (1b) and in the thickness of a reinforcing strip (3) fastened substantially to the middle of the length of the gusset, facing the added element (2) which is fastened between the connecting zones of the internal folds of the gusset with the front (1c) and back (1d) faces.
4. Bag according to any one of Claims 1, 2 and 3, characterized in that openings (O1) and (O2) have a substantially oblong general shape and are placed symmetrically, about the median line (c) of the two folds (a) and (b), bounding a central strip which constitutes the handle as such (P), after having introduced a hand through the said openings (O1) and (02).
5. Bag according to Claim 4, characterized in that profiled slits (F) are made transversally in the thickness of the folds (a) and (b) of the gusset (1b), facing the added element (2), and on either side of the openings (O1) and (O2).
6. Bag according to Claim 3, characterized in that profiled slits (F) are made transversally in the thickness of the folds (a) and (b) of the gusset (1b) and in the thickness of the reinforcing strip (3) facing the added element (2), and on either side of the openings (O1) and (O2).
7. Bag according to Claim 1, characterized in that the openings consist of profiled slits (F1) made in the thickness of the folds (a) and (b) of the gusset (1b), facing the added element (2) which is fastened to the interior of the folds of the gusset, in a sealed manner, the said slits (F1) being placed symmetrically, about the median line (c) of the two folds (a) and (b), bounding a central strip which constitutes the handle as such (P), after having introduced a hand through the said slits.
8. Bag according to Claim 1, characterized in that the openings consist of profiled slits (F1) made in the thickness of the folds (a) and (b) of the gusset (1b) and in the thickness of its reinforcing strip (3) fastened facing the added element (2) which is fastened to the interior of the folds of the gusset, in a sealed manner, the said slits (F1) being placed symmetrically, about the median line (c) of the two folds (a) and (b), bounding a central strip which constitutes the handle as such (P), after having introduced a hand through the said slits.
9. Bag according to any one of Claims 1 to 8, characterized in that the added element (2) has a substantially quadrangular planar shape.
10. Bag according to Claim 9, characterized in that the substantially quadrangular planar shape is dimensioned to completely cover the openings (O1) and (O2) or slits (F1) in order to create a seal inside the bag.
11. Method for fabricating a plastic bag with gussets (1a) and (1b) according to Claim 1, comprising the following steps:

    - a plastic film (f) is continuously unwound and subjected to operations to bound, between the two lengthwise sides of the film, a portion constituting the front face (1c) of the bag, a portion constituting one of the gussets (1b), a portion constituting the back face (1d) of the bag, another portion constituting the other gusset (1a);

    - one of the portions constituting one of the gussets (1b) is continuously subjected, at regular intervals, to at least one operation for constituting openings acting as a handle;

    - the film is subjected to various folding, cutting and welding operations, to produce a bag having a bottom, lengthwise sides with gussets, and an opening.
12. Method according to Claim 11, characterized in that:

    - openings (O1) and (02) are made in the thickness of the portion constituting one of the gussets (1b) for the passage of a hand, and placed symmetrically about the median line of the said portion;

    - an element (2) is added on and fastened, in a sealed manner and on the side of the film for constituting the interior of the bag, over substantially the width of the portion constituting one of the gussets (1b), and at the said openings or slits, in order to block it completely.
13. Method according to Claim 11, characterized in that:

    - a reinforcing strip (3) is fastened at the openings acting as a handle;

    - openings (O1) and (O2) (3a) and (3b) are made in the thickness of the portions constituting one of the gussets (1b) and in the thickness of the reinforcing strip (3), for the passage of a hand, and placed symmetrically about the median line of the said portion;

    - an element (2) is added on and fastened, in a sealed manner and on the side of the film for constituting the interior of the bag, over substantially the width of the portion constituting one of the gussets (1b), and at the said openings or slits, in order to block it completely.

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