EP1864918A1 - Bag for transporting and storing loose goods - Google Patents

Abstract

The bag has two sides, a base and a top, which are stitched one to another along their edge. The top of the bag is formed of two superposed sheet parts (4a, 4b), each part has one or more preset air permeability zones. The zones of one part are not opposite to the zones of another part. The zones are situated near center of the part (4a) so that the zones are as remote as possible from the center of the part (4b).

Description

The present invention relates to a bag for transporting and storing bulk goods.

The bags for the transport and storage of bulk goods are commonly called "big bags" in the circles concerned, as in the technical literature, Anglo-Saxon or not.

Within a rather large group, because of the diversity of applications, the bag object of the present invention relates more particularly to the transport and storage of powdered products or goods, more particularly pulverulent products and goods for agrifood industry, including cocoa powder and milk powder as the most representative examples.

The bags for transporting and storing powdered goods, and those according to the invention also, consist of a bottom and four vertical sides of woven fabric, nowadays synthetic, essentially polypropylene or polyethylene. These bags are equipped with lifting straps, usually sewn along their four vertical edges. Their upper part, forming roof, is generally non-carrier (it does not participate in the lifting of the load), and is therefore usually performed in a canvas of a weight less than that of the rest of the bag. Said upper part is most of the time provided with a filler neck.

In the field of transport of products intended for the food industry, but this also applies to other applications, a priority attention is devoted to the waterproofness of the bag, the fear of contamination being omnipresent. This essentially results in two ways, namely on the one hand that the fabrics constituting the bottom and the sides or even the upper part of the bag are canvas, single or double, but still laminated, or double laminated . On the other hand the seams are made with application of a sealant so as to plug any gap left otherwise by the seam.

Sometimes, the bottom and sides of the bag are lined with a plastic film, affixed hot if necessary, properly waterproof.

Everything converges, therefore, by necessity, that the bags concerned are almost air chambers as we try to make them airtight.

This medal dedicated to the fight against contamination has unfortunately a setback.

In fact, the cleanliness of the pulverulent materials that it is necessary to carry is that during the filling of the bag, the pulverulent products store a quantity of air that the laws of the physics make it possible to explain, but which nevertheless defies understanding.

This phenomenon has been observed for a long time, so much so that corrective measures have been adopted.

Thus, it is now common that on the mouths or pipes filling facilities, pulsed or not, which introduce the goods into the bags via the channel of their chute, the filling facilities comprise a parallel suction channel for removing the air bag as the bag fills.

These arrangements installed on the filling units of course reduce the phenomenon, but clearly not enough, far from it.

The fact remains that the pulverulent goods are filled with air whatever is done during filling and that this amount of air is gradually released from the goods with the passage of time. The bags being almost waterproof for the compelling reasons that have been mentioned, the result is inevitably that the bags are transformed into balloons, that they lose all stability and become positively dangerous under certain circumstances.

To illustrate the magnitude of the problem, it is sufficient to emphasize that the goods inside the bag is reasonably stable and compact over the first thirty centimeters of height from the bottom. At man's height, either halfway up the bag or a meter from the bottom, it is easy to push the arm to the elbow by pushing the canvas of the bag towards the center of the bag.

It is understood in these conditions that the stacking of the bags on each other is totally excluded. The storage of bags in stores with bays up to 10 meters high or more is also prohibited because the bags, unstable as possible, may collapse to the void and fall a few meters below to at best burst and lose the goods and at worst, unfortunately, hurt or kill the workers passing through.

In short, the consequences of this puzzle relating to the air contained in pulverulent materials are in all cases very disabling in comparison with other loads, potatoes for example, and are sometimes very dramatic by the accidents to which they give rise.

In these conditions, any significant improvement is really welcome, even if it can not pretend to solve everything alone.

The object of the present invention is to provide a bag for the transport and storage of powdered products or goods, more particularly powdery products and goods intended for the food industry, with arrangements allowing at least part of the air contained in the bag to escape, without the powdered material transported escapes with him.

To this end, the present invention relates to a laminated and waterproofed canvas bag for transporting and storing products or goods as defined in claim 1.

• la figure 1 illustre un sac selon l'art antérieur;
• la figure 2 illustre le mode de construction de la partie supérieure d'un sac selon l'art antérieur;
• la figure 3 illustre une vue en perspective éclatée du dessus du sac selon une première variante de l'invention;
• la figure 4 illustre une vue en perspective éclatée du dessus du sac selon une deuxième variante un peu différente de la première;
• la figure 5 illustre une vue de dessus du dessus du sac selon la deuxième variante et met en exergue les ajouts que cette deuxième variante autorise.

By way of example, a bag according to the invention is described below with reference to the drawing in which:

• Figure 1 illustrates a bag according to the prior art;
• Figure 2 illustrates the method of construction of the upper part of a bag according to the prior art;
• Figure 3 illustrates an exploded perspective view of the top of the bag according to a first variant of the invention;
• Figure 4 illustrates an exploded perspective view of the top of the bag according to a second variant slightly different from the first;
• 5 illustrates a top view of the top of the bag according to the second variant and highlights the additions that this second variant allows.

In Figure 1, it recognizes the bag 1, two sides 2 are visible. The four sides of the bag, as well as its bottom, are made in the form of pieces of canvas. This is most often polypropylene or polyethylene fabric, without any material plays any role in the construction of the bag. The sides, the bottom and the top 4 of the bag are sewn to each other along their edges. We also recognize the lifting straps or belts 3, generally applied to the four corners of the bag and sewn along the vertical edges of the bag, on a greater or lesser height.

In the bags specifically concerned by the present invention, the top 4 of the bag has a filler neck 5. The top of the bag is in general shaped to form a dome more or less curved. This result is obtained by giving the sides of the top piece a longer length than the sides of the bag. Thus, if the bag is of square section, which is the most common, and the sides have a width of 100 centimeters, it will be used to form the top of the bag a square piece of 110 to 120 centimeters side for example, giving a more or less pronounced bending.

Finally, although it is not visible in the drawing, and unimportant for the invention, it is noted that in general the bottom of the bag is provided with a discharge chute.

The grammage of the piece of cloth used to make the top of the bag is generally lower than that of the fabric used for the sides and the bottom, because of the fact that the top of the bag is carried by the rest of the bag and that there is no force applied during lifting. It is in fact the lifting straps or belts 3 to which the whole of the necessary force is applied.

Although of a lighter weight, the piece of fabric constituting the top of the bag is generally treated in the same way as the other parts forming the bag, mainly by rolling, or even by affixing a film on its inner face, this to contribute to the waterproofness of the bag as already mentioned in the introduction.

In FIG. 2, which still illustrates the state of the art according to the prior art, it is observed that, before it is fastened by stitching on the sides 2 of the bag, the top piece 4 is presented as a linen coupon, at the center of which the filler neck 5 was fixed by stitching.

In Figure 3, we see that the bag top is not composed of a single piece of cloth, but of several pieces, at least two pieces 4a and 4b. The figure shows the upper part 4b already provided with the filler neck 5, this only for comparison with Figure 2 illustrating the prior art. In reality, the pieces of cloth (4a and 4b) forming together the top 4 of the bag are assembled by sewing before the chute, which constitutes an insert, is then attached to the top 4 of the bag, formed of its parts 4a and 4b. By using two pieces where there is usually only one, we can choose a lighter weight and therefore more advantageous to make parts 4a and 4b.

It is observed that each of the parts 4a and 4b forming the top 4 of the bag, is provided with zones of air permeability comprising perforations 6. These perforations can be made in various ways, in particular one which consists of in the areas concerned only, passages in a sewing machine whose wire has been removed. The bare needle leaves lines of regular perforations and the diameter of the perforations, equal to the maximum of that of the needle, is perfectly suitable for the purpose of the invention which has been pointed out that it relates to the passage of air contained in the bag to the outside of it.

It is observed by comparing the location of the perforated zones specific to the outer part 4b that this location is not superimposed with that of the specific perforated areas of the inner part 4a. On the contrary, the locations of the perforated areas of one and the other parts are precisely chosen to not match, so that the perforations of a room are never opposite the perforations of the other.

Being reminded that the top 4 of the bag has the domed shape of a dome when the bag is completed, it is observed that the specific perforated zones of the outer part 4b are all further from the center of the part than the specific perforated zones of the the inner part 4a. As a result, once the bag is finished, and because of the domed shape of the top 4 of the bag, the perforated areas of the outer part 4b are located lower than the perforated areas of the inner part 4a. Thus, it is prevented that, in rainy weather for example, the water can penetrate inside the bag. The water could certainly penetrate through the perforations of the outer part 4b, but it can not go back to the perforations, located above, the inner part 4a and therefore can not penetrate inside the bag.

One could imagine that, instead of perforations made as it is said above, it is practiced in the inner parts 4a and 4b exterior cutouts forming windows in the same areas as specified above, and then lining these windows voilages forming filters. However, this more sophisticated variant faces a cost problem because its realization is much less economical than making perforations by means of a sewing machine.

In Figure 4, it can be seen that the perforated areas are this time organized further and four sectors of 90 degrees each, at a rate of one zone per sector.

In FIG. 5, the perforated zones of the outer part 4b are recognized. The perforated, non-visible areas of the inner part 4a, which are also not visible, are symbolized by hatched surfaces 7.

It is observed that additional seams 8, with no other function than that described below, are made through the two parts 4a and 4b forming the top 4 of the bag. The exact arrangement of the additional seams, as well as their length, are intended only to form baffles interposed between the perforated areas and making more complex and more uneven the path from a perforated area of a room to perforated areas of the other room. Only two sets of additional seams have been shown on the drawing, so as not to weigh down the figure, but it goes without saying that the last two corners of the bag are also equipped.

These baffles make it virtually impossible to raise water from the perforations of the outer part 4b to those of the inner part 4a.

In the same way, the matter contained in the bag, of which we can not absolutely exclude that it is, partly very residual, carried by the air in its path from the inside of the bag to the outside, via the various perforated zones, will not be able to overcome the obstacle of the additional baffles 8 and will accumulate at worst between the two parts 4a and 4b forming the top 4 of the bag, but without being able to get out.

The first variant of the bag according to the invention also prevents the contained material from escaping the bag, but to a less radical extent.

Thus, the water whose bag according to the invention does not allow entry into the bag, or the transported material that can not escape, fail to cross the double barrier consisting of non-perforated zones. corresponding. However, the air will always find its way to the outside of the bag, regardless of the route to take.

The advantages of the bag according to the invention are to provide a better solution than all those known to the problem of the air contained in the bags for the transport of powdery materials, and this without significant additional cost, because the perforation by means of a sewing machine has a ridiculous price. On the other hand, the tiny sacrifice of cost made because of the use of two pieces of canvas of a weight less than that of the usual part they replace, is largely offset by the capacity of the bag to let s' escape the enclosed air, and he alone, to the outside of the bag.

Claims (5)

Laminated and waterproof canvas bag for the transport and storage of powdered products or goods, more particularly powdered products and goods for the food industry, the bag consisting of a bottom, sides and a top allowing domed-shaped bending, characterized in that the top (4) of the bag (1) is formed from at least two superposed pieces of fabric (4a and 4b), each of these parts having one or more zones ( s) predetermined (s) permeability to air, said permeability zones of a room not facing the permeability zones of another room; and the permeability zones being located near the center of the room with respect to the innermost part (4a), whereas these areas are located as far as possible from the center of the room with respect to the most outside (4b). Bag according to claim 1, characterized in that each permeability zone is provided with a series of orifices (6) resulting from the perforation of the fabric in these places. Bag according to claim 2, characterized in that the orifices are the result of the puncture left by the threaded needle of a sewing machine. Bag according to Claim 1, characterized in that the absence of facing the zones of permeability of the different pieces does not result exclusively from their different distance from the center of the pieces, but results from more than one distribution by sectors, areas with permeable areas of a room that do not overlap with areas in other rooms. Bag according to claim 4, characterized in that additional seams (8) are made through the parts so as to form baffles making the enclosed path leading from one sector to the sectors adjacent thereto more complex.

Images