MXPA04007712A

MXPA04007712A - Closure assembly in a bag.

Info

Publication number: MXPA04007712A
Application number: MXPA04007712A
Authority: MX
Inventors: Philippe Eggermont
Original assignee: S2F Flexico
Priority date: 2002-02-08
Filing date: 2003-02-06
Publication date: 2004-11-10
Also published as: CN1328126C; FR2835810A1; DE60314983D1; US20050078891A1; EP1472148A2; JP2005516860A; JP4255837B2; DE60314983T2; BR0303028A; DK1472148T3; FR2835810B1; CN1642816A; WO2003066459A2; AU2003226863A1; EP1472148B1; WO2003066459A3; CA2475260A1; WO2003066459A8

Abstract

The invention relates to a closure assembly (1) comprising complementary closure sections (2) and panels (6a, 6b) for fixing said closure assembly to the internal faces of a bag. The inventive assembly is characterised in that it comprises: sealing bands (11, 13) which are disposed on the external faces of the fixing panels (6a, 6b); a precut or line of weakness (10) which is made in one of the fixing panels (6a) and which divides said panel (6a) into a first external part (61a) and a second internal part (62a), the sealing band on the panel being limited to the external part of same; and a sealing band (12) which is disposed on the internal face of at least one of the panels, each internal sealing band being disposed on the internal part of the fixing panels.

Description

CLOSING ASSEMBLY IN A BAG TECHNICAL FIELD OF THE INVENTION The present invention relates to the field of packaging bags. It relates in particular to the manufacture of bags comprising closure assemblies, in particular closure assemblies of the type of evidence of undue opening. Many packaging bags and many systems for manufacturing these have already been proposed, in particular for fastening to bag closure assemblies comprising evidence of undue opening means. Figure 1 shows an example of a known lock assembly 1. It comprises complementary profiles 2 for opening and closing the mouth 3 of a bag. The complementary profiles 2 are advantageously opened or closed by virtue of a movement slider 4. One can also see in FIG. 1 means providing the initial protection and an opening indication function, consisting of a strip 5 extending initially through the mouth of the bag and that must be broken to access the content of the latter. The means of evidence of undue opening 5 are known as such and allow a user to know whether the bag containing the product has already been opened or not. Fixing sheets 6 make it possible to fix complementary profiles to the walls 7 of the bag. The fixing of the sheets 6 takes place during a welding process, during which the fixing sheets pass between welding jaws 8. The fixing of the sheets to the mouth of the bag does not prove to be completely satisfactory, although many investigations have been carried out. conducted in this very special field. In particular, the fixing sheets must not be welded together, nor to the means of evidence of undue opening. Therefore, it is necessary to provide an intermediate part 9 between the internal faces of the sheets, which makes it possible to correctly position the evidence means of undue opening 5 or prevents welding of the sheets 6 with each other. Examples of said known bags are described and illustrated in documents FR 2 778 362.

BRIEF DESCRIPTION OF THE INVENTION The invention proposes to improve the system for fixing the sheets on the faces of the bag.

In particular, it also proposes closure assemblies, which means of evidence of undue opening do not consist of a sheet comprising a line of weakness. For this purpose, the invention proposes a closing assembly comprising complementary closure profiles and sheets for fixing the closure assembly to the faces of a bag, characterized in that it comprises: - welding strips on the external faces of the fixing sheets; - a mark or line of weakness formed in one of the fixing sheets, said mark or line of weakness delimiting the fixing sheet in a first external part and a second internal part, the external welding strip provided on the sheet being limited to the external part of it; - a strip of welding on the internal part of at least one of the sheets, each internal welding strip being located on the internal part of the fixing sheets. The invention is advantageously complemented by the following characteristics taken alone or in any of its technically possible combinations: the outer welding strip of the sheet not comprising the mark extends over the entire width of the sheet; - the outer welding strip of the sheet not comprising the marking extends only on the external part of the sheet; - the closing profiles are complementary, of the female / male type. - the closing profiles comprise a movable slider. The invention also relates to the bags comprising the closure assemblies according to the invention, the methods and machines for manufacturing the closure assemblies and the bags comprising these assemblies.

BRIEF DESCRIPTION OF THE DRAWINGS Other features, aims and advantages of the invention will emerge from the following description, which is illustrative and not limiting and which must be read with respect to the accompanying drawings, in which. - Figure 1, already commented, schematically illustrates a bag according to the prior art comprising a closure assembly with a sheet of evidence of undue opening comprising a line of weakness; - Figure 2 schematically illustrates a closure assembly according to the invention; - Figure 3 schematically illustrates a closure assembly instead of the mouth of a plastic bag. - Figure 4 illustrates a closure assembly according to the invention, whose element of evidence of undue opening has been opened; - Figure 5 illustrates a mode wherein the packing bag is filled after fixing the closure element; - Figure 6 illustrates a closure assembly, whose fastening strip is on the opposite sheet compared to the embodiment illustrated in figure 2; and - Figure 7 illustrates a closure assembly that combines the modalities of Figures 2 and 6.

DETAILED DESCRIPTION OF THE INVENTION As indicated above, the present invention relates to the manufacture in an assembly machine for closing resealable bags, these bags comprising a closure assembly with fixing sheets to form evidence of undue opening means. The present invention can be applied equally well to automatic bag-making machines with horizontal travel and to automatic bag-making machines with vertical travel. Furthermore, the present invention applies equally well to automatic bag making machines with filling during a step subsequent to manufacturing and possibly geographically separated from the place of manufacture, and to manufacturing machines, with filling and closing - of the "Form, Fill and Seal "(FFS) in accordance with the terminology in English generally used - in one place and during successive steps.

Therefore, the present invention is preferably and advantageously applied to machines of the FFS type with vertical travel. Figure 2 schematically illustrates a closure assembly 1 according to the invention. It comprises complementary profiles 2 that allow the opening and closing of the mouth of the bag. The complementary profiles 2 advantageously open and close by virtue of a movement slider 4. The assembly, however, may not include a slider. The complementary closure profiles 2 are advantageously of the female / male type. However, it is possible to contemplate other types of complementary profile. The fixing sheets 6a and 6b support the profiles 2 and make it possible to fix them to the walls of a bag. A line of weakness or mark 10 parallel to the profiles is formed on one of the sheets 6a. The mark 10 extends substantially to the middle of the sheet 6a. Therefore, it divides the sheet 6a into two parts: a first part 61a more external with respect to the bag and a second part 62a more internal. By analogy, in the content of the present application, for the second sheet 6b, the sheet 6b will be called the "outer part" and the part 62b the "internal part". In the present description, the term "welding strip" encompasses all the possibilities of fixing a fastening sheet to a wall of the bag, such as for example thermal welding, in particular welding of the "hot melt" type, but also adhesive joints. The outer face of the outer part 61 a of the sheet 6 a is covered with a welding strip 11. The strip 1 1 is capable of fixing the sheet 6 a to the inner face of a wall of a bag. The inner face of part 61 a on the other hand, has no welding strip. The same applies to the inner face of part 61 b. Therefore, the internal faces of the parts 61a and 61b can not be welded together. According to a variant, the material of the fixing sheets is such that the internal faces do not adhere to one another during the welding process. It is possible to obtain the same result by virtue of a surface treatment process known to those skilled in the art. The inner face of the part 62b is covered with a welding strip 12, which is facing the part 62a, which is or is not covered with a welding strip. Advantageously, the part 62a does not comprise a strip, which makes it possible to save on welding material and to carry out relatively clean welds. Naturally, the welding strip can be fixed to part 62a, and not to 62b. Figures 6 and 7 differ from Figure 2 only through the placement of the welding strip on the inside of the sheets 6a and 6b. Thus, the parts 62a and 62b can be welded to each other during the passage of the closing assembly between the welding shoes. The purpose of said welding is to form an element of the type of evidence of undue opening, which satisfies the function of the first opening indication. The inner face of the sheet 6b is covered with a welding strip 13 capable of providing the fixing of the sheet 6b to the inner face of a bag. Figure 3 schematically illustrates the upper part of a bag 20 comprising in its mouth 3 a closure assembly 1 according to the invention. The fastening of the sheets 6a and 6b takes place during a joining process with welding or with adhesive during which the sheets 6a and 6b pass between the welding jaws or connection 8. After welding, the external faces of the sheets 6a and 6b are fixed to the internal faces of the walls 7 of the reclosable bag 20. In the same way, the thermal welding process welds together the internal faces of the parts 62a and 26b. The assembly 1 therefore constitutes a closure of the type of evidence of undue opening, the weld 12 being hermetic. This closing of evidence of undue opening can be opened by a user under the mark 0. Figure 4 schematically illustrates the operation of the opening after the first opening of the device of evidence of undue opening, ie after cutting the mark 10 After opening the profiles 2 under the slider 4, the user exerts enough force on the sheets 6a and 6b to break the line of weakness or mark 10. After breaking the line of weakness or mark 10, the part 62a remains welded to the sheet 6b, the part 61a remains welded to the wall of the bag 20. The arrow 21 schematically shows that the user can have access to the interior of the bag 20. The user can therefore open or close the profiles 2 as desired . The invention also relates to the manufacture of the assemblies 1. In accordance with this manufacturing method, the complementary profiles 2 are welded onto the fastening sheets 6a and 6b. The fastening sheets 6a and 6b can also be extruded in one piece on the profiles. A mark is made or a line of weakness 10 occurs in one of the fixing sheets, which is referenced with the number 6a for clarity of the description. The welding strips are then applied to the sheets 6a and 6b. The welding strips on the outer faces of the sheets extend on the outside of the sheet 6a with respect to the mark or line of weakness 10 and on the entire face for the sheet 6b. The welding strips on the internal faces of the sheets extend over the inner part of the sheet or the sheets 6a and / or 6b with respect to the mark or line of weakness 10. The internal faces of the external parts with respect to the Mark 10 does not include any welding strip. Advantageously, only one internal part comprises a welding strip. The complementary profiles advantageously comprise a mobile slider to assist with opening / closing. The slider can be made of metal or plastic. The walls of the bags can be made of any material such as plastic, cardboard or paper material. The invention also relates to a method of attaching closure assemblies to recessable bag mouths. According to this method, the closure assembly is passed through the mouth of the bag, which is formed by means known per se, the movement taking place between the welding shoes. The welding shoes allow the welding strips to be fixed to the walls of the bag and to weld the internal parts of the fixing sheets together. The welding of the fixing sheets to the inner faces of the walls of the bag can take place simultaneously on the two walls, or it is possible to weld a first sheet, carry out several operations, such as filling the bag for example, and then weld the second sheet. The machines for manufacturing the closure assemblies comprise means capable of applying the welding strips to the appropriate faces of the fixing sheets. They also comprise means capable of forming a line of weakness or a mark on one of the fixing sheets. The machines for fixing the closure assemblies to the mouth of the bags comprises means capable of making the closure assemblies pass flush with the mouth of the bags, and between means capable of welding the fixation assemblies to the walls. These means, in particular, may comprise welding shoes. The movement means can be means of longitudinal movement or means of transverse movement. Upstream of the closure, the machines comprise bag forming means known as such. The filling of the bag with the product can be carried out on the manufacturing site of the bag. It can be carried out, for example, before fixing the closure assembly. Where the filling is carried out after fixing the assembly to the mouth of the bag in the same place or elsewhere, it is subsequently possible to provide means for welding the fixed assemblies to the wall of the bag without forming the closing of evidence of undue opening. Therefore, the filling can take place through the internal space between the fixing sheets. These means may comprise, for example, means which interpose between the internal parts of the fixing sheets during the welding step. In accordance with a variant illustrated in figure 5, the welding strips 1 1 and 13 apply only to the external faces of the parts 61 a and 61 b. Therefore, initially, only external parts are welded. The formation of the evidence of undue opening will be done by welding the parts 62a and 62b after filling the bag. The filling of the bag can take place according to other variants. It is possible, for example, to fix a fastening sheet to an inner face of one of the walls of the bag, the evidence element of undue opening being already formed, to carry out the filling of the bag, and then to fix the other sheet to the other wall. Therefore, the filling can take place through the outside, namely, between a wall of a bag and a fixing sheet. The filling can also be effected through the end of the bag opposite the mouth where the closure assembly is fixed. The filling machine may comprise means for carrying out the welding of the "hot melt" type. It may also comprise attachment jaws with adhesive. It should be established that the above description in no way presupposes the position of the machine. For example, it may be a case of vertical or horizontal movement and the fastening of the closure assembly may take place longitudinally or transversely to the movement of the packaging sheet.

Claims

NOVELTY OF THE INVENTION CLAIMS 1. - A closure assembly (1) comprising complementary closure profiles (2) and sheets (6a, 6b) for fixing the closure assembly to the internal faces of a bag, characterized in that it comprises: - welding strips (11, 13) on the external faces of the fixing sheets (6a, 6b); - a mark or line of weakness (10) formed in one of the fixing sheets (6a), said mark or line of weakness delimiting the fixing sheet (6a) in a first external part (61 a) and a second internal part (62a), the outer welding strip provided on the sheet being limited to the outer part thereof; - a welding strip (12) on the internal part of at least one of the sheets, each internal welding strip being located on the internal part of the fixing sheets. 2 - The assembly according to claim 1, further characterized in that the external welding strip of the sheet (6b) that does not include the mark extends over the entire width of the sheet. 3. - The assembly according to one of claims 1 or 2, further characterized in that the outer welding strip of the sheet (6b) not comprising the mark extends only on the external part (61 b) of the sheet (6b). 4. - The assembly according to one of claims 1 to 3, further characterized in that the closing profiles (2) are complementary, female / male type. 5. - The assembly according to one of claims 1 to 4, further characterized in that the closing profiles (2) comprise a movable slider (4). 6. - A reclosable bag (20) comprising a body that bends on itself and a mouth to which the closure assembly is fixed, comprising complementary closure profiles, and sheets for fixing the closure assembly to the internal walls of the bag, characterized in that it comprises: - welding strips (11, 13) on the external faces of the fixing sheets (6a, 6b); - a mark or line of weakness (10) formed in one of the fixing sheets (6a), said mark or line of weakness delimiting the fixing sheet (6a) in a first external part (61a) and a second internal part ( 62a), the outer welding strip provided on the sheet being limited to the outer part thereof; - a welding strip (12) on the internal part of at least one of the sheets, each internal welding strip being located on the internal part of the fixing sheets. 7 - The bag according to claim 6, further characterized in that the outer welding strip of the sheet (6b) that does not comprise the mark extends over the entire width of the sheet. 8. The bag according to one of claims 6 or 7, further characterized in that the outer welding strip of the sheet (6b) that does not comprise the marking extends only on the outer part (61b) of the sheet (6b) ). 9. - The bag according to one of claims 6 to 8, further characterized in that the closing profiles (2) are complementary, of the female / male type. 10. - The bag according to one of claims 6 to 9, further characterized in that the closing profiles (2) comprise a movable slider (4). 11. - A method of manufacturing a closure assembly comprising complementary closure profiles (2), and sheets (6a, 6b) for fixing the closure assembly to the internal faces of the walls (7) of the bag, according to which: - a mark or line of weakness (10) is formed in one of the fixing sheets (6a), said mark or line of weakness delimiting the fixing sheet (6a) in a first external part (61a) and a second external part (62a); - welding strips (11, 13) are applied to the external walls of the fixing sheets (6a, 6b), the external welding strip provided on the sheet comprising the line of weakness or brand being limited to the outside of the same; - welding strips (12) are applied to the inner wall of at least one of the strips in the internal part of the fixing sheets. 12. - The method according to claim 11, further characterized in that it also comprises the step according to which a mobile opening / closing slider is fixed to the complementary closure profiles (2). 13. - A method of manufacturing a reclosable bag according to which a closure assembly (1) comprising complementary closure profiles and sheets for fixing the closure assembly to the bag are fixed, characterized in that it comprises the steps according to which: - two walls (7) are formed that delimit a mouth (3); - welding strips (1, 13) are welded to the external walls of the fastening sheets on the inner faces of the walls (7) of the bag flush with the mouth, one of the sheets comprising a mark or line of weakness able to break at the moment of opening for the first time, the external welding provided on said sheet being limited to the external part thereof; the bag (20) is filled with the product; - the internal faces of the sheets (6a, 6b) are welded together by means of a welding strip (12) present on at least one of the sheets, each internal welding strip to the sheets being located on the inside of the fixing sheets. 14. - The method according to claim 13, , further characterized in that the filling of the bag is carried out prior to fixing the closure assembly. 15. The method according to one of the claims 13 or 14, further characterized in that it comprises a passage according to which a mobile opening / closing slider (4) is fixed to the complementary closing profiles (2). 16. The method according to one of claims 13 to 15, further characterized in that the welding of the welding strips is of the "hot melt" type welding. 17. - A machine for manufacturing a closure assembly comprising complementary closure profiles (2) and sheets (6a, 6b) for fixing the closure assembly to the internal faces of the walls of the bag (20), characterized in that it comprises : means capable of producing, in one of the fixing sheets, a line of weakness or mark (10), said line of weakness or mark delimiting the fixing sheet in a first external part and a second internal part; - means capable of applying welding strips (11, 13) to the external walls of the fixing sheets, the external welding strip provided on the sheet being limited to the external part thereof; - means capable of applying a welding strip (12) to the internal part of at least one of the sheets and to the internal part of the fixing sheets. 18. - A machine for manufacturing a reclosable bag (20) comprising means for fixing a closure assembly (1) comprising complementary closure profiles (2) and sheets (6a, 6b) to fix the closure assembly to the bag, characterized in that it comprises: - means able to form two walls delimiting a mouth (3); - means capable of welding welding strips (11, 13) located on the external faces of the fixing sheets on the inner faces of the walls (7) at the level of the mouth, one of the sheets comprising a mark or line of weakness able to break at the moment of opening for the first time, the external welding provided on said sheet being limited to the external part thereof; - means capable of filling the bag with a product; - means capable of welding together the inner faces of the sheets by means of a welding strip present on at least one of the sheets, each internal welding strip to the sheets being located on the internal part of the fixing sheets. 19. The machine according to claim 18, further characterized in that it comprises means for effecting a welding of the type of "hot melt" welding.