FR2509266A1 - Box profile plastic sacks with oversized internal linings - to ensure full fitting and load distribution - Google Patents

Abstract

Flexible sacks have tubular bodies with impermeable coatings or, pref. complementary linings slightly greater in width and anchored by stitching near the base of the sack, where the linings are folded with deeper sidewall gussets than the main sack bodies. For sacks for holding bulk powdered, granular or paste materials, to avoid any weaknesses characteristic of longitudinal stitched seams. Esp. claimed for sacks where the outer body is of woven polypropylene and the lining is of polyethylene. The linings are sealed by a transverse weld above the level of stitching securing the lining into the main sack. The lining may be introduced diagonally into the outer sack, with flattened borders, or may straddle the inner faces of the creased sidewalls of the main sack. Use of an oversize internal lining ensures a close fit between the lining and sack to share the contained load when being lifted. The gusset wall profiles stabilise the sack profile section to permit stacking. The sacks may be totally or partially open-topped.

Description

 The present invention relates to a large flexible packaging, generally referred to as a container, used for packaging, handling, storage and transport of bulk, powdery, granular or semipatous products. This container can be of the lost type or recyclable (several rotations).

 The object of the present invention is to provide such packaging, which is practical, solid and inexpensive, in this case a flexible container, which can occupy a small empty volume and having a large filling volume, and which can be industrially and automatically produced without assembly (by seams for example) of several elements forming its different faces, hence an advantageous cost price and increased resistance and safety.

 Flexible containers currently used, with a large capacity and possibly doubled, are described in the patent applications for invention in France Nos 77 19647 and 79 14033. They are produced from a strip of material folded and sewn on three sides constituting the longitudinal edges and the bottom of the container; they therefore have side seams which make the packaging fragile.

 To remedy this major drawback, the subject of the present invention is a flexible container, possibly with a closed mouth, for powdery, granular or semi-pasty products, comprising an envelope possibly provided with a lining, characterized in that the envelope is in the form of 'a sheath without longitudinal seams, made of flexible material and with bellows, which is closed by any connecting means, at one of its ends forming the bottom of the envelope and of the container.

 The lining may be formed by a coating of a waterproofing material covering the external face of the jacket, or by an internal bag made of a waterproof material which, like the envelope, is in the form of a sheath without longitudinal seams, made of material flexible and with bellows, closed by a weld line near one of its ends forming the sealed bottom of the inner bag and of which this same end, below said weld line, is integral with the closed bottom of the envelope by any means link.

 The connecting means mentioned in this patent can between seams, stapling, pn gluing, welding or the like. This is how the bottom of the envelope can be closed per year minus a seam, which also crosses and maintains the bottom of the inner bag, below the weld line of the latter, so as to make them united by their bottoms. the envelope and the internal bag. To perfect the seal and more securely join the envelope and the internal bag, the end of the envelope forming the bottom thereof can be folded over the end of the bag. internal located below the weld line thereof, - so that the means for closing the folded end of the envelope are simultaneously the means for connecting the funds of the envelope and the internal bag.

 The internal bag preferably has dimensions (diameter and height) greater than those of the envelope; its bellows are then deeper than those of the envelope and it is folded in Z longitudinally inside thereof.

 The side walls of the inner bag can also be made integral with the envelope by gluing or at least partial welding, for example by points or by lines.

 To have the above-mentioned characteristics, the container according to the present invention is manufactured from a raw material of tubular section, produced by weaving, extrusion or other processes allowing continuity of manufacture, and preferably having a presentation with lateral bellows.

The aims and advantages of this so-called tubular presentation with lateral bellows and of the other specific features of this container are as follows
1 - Reinforce the resistance of the container, the weak points being generally located at the longitudinal seams.

 2 - Avoid any tearing and allow a better distribution of the load and the effort when handling the full bag with the different gripping means usually used, such as ropes, slings, bars, forklift forks, hook, etc. ...

 3 - Allow a better deployment of the container delivered flat (and the internal bag if there is one) during filling operations.

 This filling is then even possible without prior introduction of gas (such as compressed air for example), usually necessary for the deployment of the containers without bellows made from two flat fabrics sewn together to form a tube.

 4 - Allow a better obtaining of a parallelepiped shape after filling, which facilitates storage and stacking, the bellows helping to form a bag with a rectangular or square bottom.

 5 - Reduce, still because of the bellows, the manufacturing surface and the presentation surface, which is interesting in particular in the case of large containers.

 6 - Facilitate the holding in place of the internal bag (if it exists) and its deployment, due to the envelope-internal bag connection.

 7 - Obtain that the internal bag, during filling, taking into account its dimensions larger than those of the envelope, fits perfectly inside the container and does not support the weight of the contents alone.

 When the container is closed mouth, the upper edge of the envelope is then closed by any connecting means and an opening for filling the container is provided on said edge or on a face of the envelope near this edge. This opening allows simultaneous deaeration during filling. It can also be provided that the bottom of the bellows de.l'envelope is split, near the upper edge thereof, on S to 30 cm for example, to facilitate the escape of air and for insertion possible means of lifting and handling the container, the load of which can be from 50 kg to several tonnes.

 The tubular raw material used for the envelope can be various fabrics or fabrics, it can be natural or synthetic (polypropylene or polyethylene for example), be woven or not, or even be paper.

The inner bag is made of an impermeable material such as an elastomer or a waterproof plastic, for example polyethylene.

Particular embodiments of the container according to the invention will be described below, by way of purely indicative and in no way limitative, with reference to the attached drawing in which
Figure 1 is a schematic perspective view of a container of the open mouth type.

 Figure 2 is a sectional view along line II-II of Figure 1.

 Figure 3 is a schematic perspective view of a similar container provided with an internal bag.

 FIG. 4 is a sectional view along line IV-IV of FIG. 3.

 Figure 5 is a cross-sectional view of the same container showing a different position of the inner bag.

 Figure 6 is a schematic elevational view of a container according to the invention. -Type .to closed mouth.

 Figure 7 is a sectional view along line VII-VII of Figure 6.

 Figure 8 is a schematic elevational view of a container such as that shown in Figure 6, but additionally provided with an internal bag.

 Figure 9 is a sectional view along Line IX-IX of Figure 8.

 Figure 10 is a cross-sectional view of the same container showing a different arrangement of the inner bag in the container.

 The flexible container according to FIG. 3 is made up of an envelope 1 cut from a sheath without longitudinal seams, advantageously of woven polypropylene, this sheath being able to be or not coated internally with a layer of waterproofing material. This sheath is closed at one of its folded ends 2 by two seams 3 and 4. It has two longitudinal bellows 5 and 6.

 According to FIG. 3, the container is provided with an internal bag 7 made of an impermeable material, for example polyethylene. This internal bag is also produced in a sheath without longitudinal seams and with bellows 8 and 9.

It is closed by a weld line 10, near its lower end, and its part located below this line 10 is housed in the fold 2 of the bottom of the len- veloppe 1 and is made integral with this bottom by the seams 3 and 4, which pass through both the walls of the envelope 1 and those of the internal bag 7. This bag is thus securely held in place inside the envelope, which is particularly important during emptying the container.

 Figures 4 and 5 show two possible positions of the inner bag inside the envelope, before using the container: the bellows of the envelope can be inserted into those of the inner bag (Figure 5), but , preferably, the bellows of the inner bag are placed in the diagonally opposite parts a and d or b and c of the envelope, as shown in FIG. 4. It can be seen in FIGS. 3 to 5 that the bellows of the bag internal are deeper than those of the envelope and that the internal bag is longer than the envelope and it therefore has a fold in Z 11, to be however fully accommodated in the envelope. When filling, these differences in dimensions mean that the internal bag perfectly hugs the envelope and is well supported by it. Welding points or lines 12 further improve the connection of the two elements of the container and good retention in place from one to the other. Welding can be carried out by hot fusion of the material of the two elements.

 After filling, the upper part of the internal bag or, simultaneously, of the internal bag and the envelope is closed by a link.

 In a particular case, such a container of the open mouth type has a height of 2,320 mm and a width, flat, before use, therefore bellows tucked in, of 700 mm for the envelope and 630 mm for the internal bag, the diameters, after deployment of the container, being 1200 mm for the envelope and 1250 mm for the internal bag> which is made of polyethylene 70 microns thick, while the envelope is made of woven polypropylene with a weight of 110 g / m2 .

 Figure 6 shows a container without internal bag, but of the closed mouth type. The envelope 1 is in this case closed at its upper part, as at its lower part, that is to say by two seams 13 and 14 on a fold 15 of the top of the envelope, this sealing being effected on both sides. 'Another of a median cut in V 16 intended to allow filling. The bottom of the longitudinal bellows 5 and 6 is split at 17 and 18 below the fold 15 * therefore close to the upper edge of the envelope. These slots activate the evacuation of air during filling and allow the installation of a gripping member for lifting and handling the container. FIGS. 8 to 10 show the same container equipped with an internal bag 7 with a Z-fold 11. This internal bag is similar to that shown in FIGS. 3 to 5.

It is closed near its bottom by a welding line 10 and it is connected to the casing 1 by its bottom and by points or by welding lines 12, as described above. It is placed in the envelope (Figures 9 or 10), as in the case of the open mouth container.

 The internal bag 7, after filling with the notch 16 of the envelope 1> is closed at its top by a link.

We can also tie the top of the envelope below the notch 16. The closed mouth container provides better protection of the contents and allows, with less risk and more ease, handling by various means.

 In a particular case, such a closed-mouth container has a height of 2140 mm (envelope) and 2400 mm (internal bag deployed). The internal bag is made of polyethylene with a thickness of 70 microns, it has, flat, retracted bellows, a width of 630 mm and, deployed, a diameter of 1250 mm. The envelope is made of woven polypropylene with a weight of 110 g / m2; it has, flat, blown in, a width of 700 mm and, when deployed, a diameter of 1200 mm.

 Modifications of detail in the field of technical equivalents can be made to the containers described above, without going beyond the ambit of the present invention.

Claims (11)

RESELL I CATI ON S  1.- flexible container possibly with closed mouth, -for powdery, granular or semi-pasty products, comprising an envelope possibly provided with a lining, characterized in that the envelope (1) is in the form of a seamless sheath longitudinal, of flexible material and with bellows (5, 6), which is closed by any connecting means (3, 4), at one of its ends forming the bottom of the envelope and of the container.  2.- container according to claim 1, characterized in that the lining is constituted by a coating of a waterproofing material covering the outer face of the envelope.  3.- container according to claim 1, characterized in that the lining is constituted by an internal bag (7) made of a waterproof material which, like the envelope, is in the form of a sheath without longitudinal seams, made of flexible material and with bellows (8, 9), closed by a weld line (10) near one of its ends forming the sealed bottom of the internal bag and whose same end, below said weld line, is secured to the closed bottom of the envelope by any connecting means (3, 4).  4.- container according to claim 3, characterized in that the bottom of the envelope is closed by at least one seam (3, 4), which passes through and also maintains the bottom of the inner bag, below the weld line ( 10) thereof, to make integral by their funds 11 envelope and the internal bag.  5.- container according to claim 3 or 4, character ized in that the end of ltenreloppe forming the bottom thereof is folded (in 2) on ltextrEmitE of the inner bag located below the weld line 0) of the latter and in that the means (3, 4) for closing the folded end of the envelope are simultaneously the means for connecting the funds of the envelope and the internal bag.  6.- container according to any one of claims 3 to 5, characterized in that the internal bag has a diameter greater than that of the envelope, and therefore has, before the use of the container, bellows (8 , 9) deeper than those of the envelope.  7.- container according to any one of claims 3 to, characterized in that the internal bag has a height greater than that of the envelope and then has at height a fold (II) in Z to be fully housed in the envelope, before using the container.  8.- container according to any one of claims 3 to 7, characterized in that the side walls of the inner bag are made integral with the side walls of ltenve- loppe by gluing or at least partial welding (12).  9. Container according to any one of claims 1 to 8 and with a closed mouth, characterized in that the upper edge of the envelope is closed by any connecting means (13, 14) and in that an opening of filling (16) is provided on or near this edge.  10.- Container according to claim 9, characterized in that the bottom of the bellows (5, 6) of the envelope is split (at 17, 18) near the upper edge of the envelope.  11.- container according to any one of claims 3 to 10, characterized in that the envelope is made of woven polypropylene, the inner bag is made of polyethylene and said connecting means are seams.  ] 2.- container according to any one of claims 3 to 11, characterized in that the bellows (8 and 9) of the inner bag are placed, before the use of the container, in the diagonally opposite parts (a and d or b and c) bellows (6 and 5) of the external envelope.  13.- container according to any one of claims 3 to 11, characterized in that the bellows (8 and 9) of the internal bag are placed, before the use of the container, straddling the bellows (6 and 5) of the outer envelope.