EP2445814B1 - Bag intended for the transport and handling of liquid or quasi-liquid substances comprising a drain valve and a protective device for said drain valve - Google Patents

Description

Technical area

The present invention relates to a bag for the transport and handling of liquid or quasi-liquid substances and equipped with a protection device for drain valve. The bags of the present invention are generally called "big bags" or "bag in box" in industrial and transport environments, because they are intended to carry a volume of product of the order of one cubic meter or more, and that they weigh, when loaded, a ton or more.

State of the art

The "bag in box" generally comprise an outer envelope stiffened by various materials and an inner envelope consisting of a film sealing the device. Such "bag in boxes" have in particular been the subject of the US patent application US 2005/196080 and international patent applications WO 2009/010928 filed in the name of the Applicant and WO 97/20758 . The skilled person may usefully refer to it to obtain any additional information on this subject.

In this type of bag, it is necessary to provide a filling and emptying device, which is often in the form of a valve integrated in the sealed inner film of the bag, or "liner". The disadvantage of this type of valve is their positioning outside the bag. Thus, it forms a protuberance at the outer walls of the bag. This position is particularly troublesome during training and when handling the bag.

In particular, as described in the international patent application WO 97/20758 , which illustrates the preamble of claim 1, it is necessary to provide a passage for said valve in the reinforcement panel equipping the side of the bag where is positioned said valve protuberant. This passage may consist in particular of a hole drilled or cut through the reinforcing panel, the shape and positioning of said hole on the reinforcement panel being directly dependent on the shape and location of said valve on the inner wall of the bag disposed vis-a-vis the reinforcing panel. In the most usual case, the valve being in the form of a circular disc of a height of 6 to 8 cm and being positioned in the lower part of the bag, the hole formed in the reinforcing panel will have a circular shape a diameter slightly greater than that of the valve and will be positioned in the lower part of the panel. It should be noted that, despite the presence of this reinforcement panel, a significant portion of the valve protrudes beyond the panel and forms a protuberance outside the bag. Indeed, the panels used to reinforce the bags of the present invention generally have a thickness of not more than 2 cm and often a thickness of 1 cm. As seen above, this is insufficient to cover the total height of a usual valve.

This protruding position of the valve causes a major drawback when handling this type of bag. Indeed, transport units that handle this type of bag during loading or unloading may accidentally hook said valve and thus cause tearing of the inner wall of the bag on which said valve was attached. This tearing inevitably leads to leakage of the liquid or semi-liquid product contained in the bag, with the direct consequence of the loss of the spilled product and the deterioration of the surrounding environment.

Disclosure of the invention

It is therefore necessary to provide a simple and effective solution to this problem, while avoiding to completely change the structure of the bag as a whole.

A first possible solution would have been to use a reinforcement panel of greater thickness to completely cover the height of the valve and thus protect it from shocks. This panel would have been placed in place of the panel usually used in this type of bag or in addition to said panel so as to form an additional layer of protection around the valve and thus prevent any damage to the valve by the transport equipment. This solution is however excluded for two main reasons. On the one hand, by planning to add an extra thickness of panel, there is a risk of tearing the inner or outer fabric of the bag which covers said panel. This risk is even greater than the material constituting this type of panel is rigid and not deformable. The panels being substantially rectangular parallelepipeds provided with acute angles, a tear of the fabric at these angles is almost certain. On the other hand, the addition of an additional rigid panel inside the bags would generate a cost too high for the user.

The object of the present invention is therefore to provide a simple and inexpensive solution to the problem mentioned above and does not have the disadvantages of the solution described above.

For this purpose, according to the invention, there is provided a bag according to claim 1.

In an advantageous configuration of the invention, the flexible material contained in the closed compartment or compartments of the envelope is identical to the flexible material used to form the sheet defining the envelope.

In a particular configuration of the invention, the sheet defining the envelope is made of polypropylene.

In a particular configuration of the invention, the sheet defining the envelope is itself formed by the folding on itself of a base sheet of flexible material whose edges have been fixed together, in particular by welding.

In another particular embodiment of the invention, the envelope comprises exactly three closed compartments of rectangular shape, arranged to form an additional compartment in the envelope, said additional compartment being of square shape and being pierced at its center. opening serving as a passage for the drain valve.

In another particular embodiment of the invention, the sides of the envelope, with the exception of the insertion side, are formed by welding the side edges of the sheet defining the envelope.

In a particular configuration of the bag, the protection device of the drain valve is arranged so that the closed compartments of the envelope are oriented towards the outside of the bag.

In another particular configuration of the bag, the protection device of the drain valve is arranged so that the closed compartments of the envelope are oriented towards the inside of the bag.

Thus configured, the bag of the present invention allows a total recovery of the drain valve, the shocks caused during the transport of the bag being attenuated, or even eliminated, by the closed compartments filled with flexible and deformable material of the protective device.

It also avoids the risk of piercing the outer or inner fabric of the bag because the material used to form the protective device of the present invention is flexible and deformable and no sharp angle is apparent on the periphery of said device .

Brief description of the drawings

• la figure 1 représente une vue frontale de la face recto d'un dispositif de protection équipant un sac selon l'invention;
• la figure 2 représente une vue frontale de la face verso du dispositif représenté à la figure 1;
• la figure 3 représente une vue latérale en coupe du dispositif de protection de la figure 1 dans sa position finale d'utilisation;
• la figure 4 représente une vue en perspective d'un sac conforme à l'invention, avant l'introduction du panneau de renfort muni du dispositif de protection représenté à la figure 1; et
• la figure 5 représente une vue en perspective du sac représenté à la figure 4, après l'introduction du panneau de renfort muni du dispositif de protection représenté à la figure 1.

Other advantages and features of the present invention will be better understood on reading a particular embodiment of the invention and with reference to the drawings in which:

• the figure 1 represents a front view of the front face of a protective device fitted to a bag according to the invention;
• the figure 2 represents a front view of the back side of the device shown in FIG. figure 1 ;
• the figure 3 represents a sectional side view of the protective device of the figure 1 in its final position of use;
• the figure 4 represents a perspective view of a bag according to the invention, before the introduction of the reinforcement panel provided with the protection device shown in FIG. figure 1 ; and
• the figure 5 represents a perspective view of the bag shown in FIG. figure 4 after the introduction of the reinforcement panel provided with the protective device shown in FIG. figure 1 .

Detailed description of an embodiment of the invention

With reference to the figure 1 , there is shown a device for protecting a drain valve according to the invention. This protection device 10 is formed of a sheet 1 folded on itself so as to form an envelope substantially rectangular defined by its lateral edges 2A, 2B and longitudinal 2C and 2D (see figure 2 ). It is conceivable not to make the lower and upper edges of the sheet 1 coincide during its folding, the envelope then having an additional longitudinal edge 2E (see FIG. figure 2 ) disposed between the edges 2C and 2D. The lateral edges 2A and 2B will be fixed to each other by means of a fastening mode selected in particular from welding, sewing or gluing. The edges 2D and 2E left free allow the insertion of a reinforcement panel in the pocket defined below by the edge 2C and on the sides by the edges 2A and 2B. It will be advantageous to choose a width of sheet 1 substantially equal to, or even slightly greater than the width of the reinforcing panel so as to ensure easy retention of the protective envelope 10 around the panel without having to provide additional fixing means

To allow the passage of the drain valve to be protected, the device 10 is pierced right through a substantially circular opening 4, the diameter of the opening 4 being slightly greater than that of the drain valve. This form of opening is particularly suitable for accurately positioning the device 10 relative to the valve and thus prevent any movement of the device 10 during handling of the bag. Such a move could indeed reduce the protection of the drain valve.

In the preferred configuration of the invention, the sheet 1 is made of a flexible material, such as polypropylene. Of course, any other type of flexible material other than polypropylene may be used. In addition, the sheet 1 advantageously consists of a superposition of two base sheets of the same format, of flexible material and interconnected by their edge or a base sheet of flexible material folded on itself and whose edges were attached to each other. The sheet 1 thus has an internal empty space which can accommodate lining elements for increasing the thickness of said sheet 1. These lining elements may advantageously be made of sheet debris of flexible material. It goes without saying that any other flexible and deformable material can be used as trim element instead or in addition to these sheet debris. The internal empty space of the sheet 1 can moreover be divided into closed compartments by means of weld lines 3. These weld lines 3 in fact connect the front and back sides of the sheet 1. It is obvious that other known methods of attachment may be used in place of the weld to form these links front and back.

As shown on the figure 1 , such weld lines 3 have delimited three closed compartments 5A, 5B and 5C. These closed compartments of rectangular shape are distributed around the opening 4, so as to form an additional compartment 5D in the envelope, said additional compartment 5D being of square shape and being pierced at its center of the opening 4 serving as a passage at the drain valve. This provision of the compartments is advantageous because it allows to distribute in a balanced manner the compressive forces that could be exerted on the protective device 10 in particular following a shock caused during handling of the bag. It goes without saying that other forms and provisions of the compartments can be envisaged instead of the configuration represented on the figure 1 . In particular, it will be possible to increase or decrease the number of closed compartments or to modify the shape and arrangement of said compartments without departing from the scope of the invention.

With reference to the figure 3 , there is shown a sectional side view of the protective device 10 of the figure 1 once the reinforcement panel 30 has been slid inside the pocket formed by the device 10 and the drain valve 27 has been inserted inside the hole T of the reinforcement panel 30 and the opening 4 of the device 10. As seen in this figure, the drain valve 27 is integral with the inner casing 25 of the bag containing the liquid or semi-liquid products. This figure allows us to see that the drain valve 27 is completely protected on the one hand by the reinforcement panel 30 and on the other hand by the protection device 10. In particular, it can be seen that the length of the valve 27 protruding from the inner envelope 25 of the bag, called the valve height H, substantially corresponds to the accumulation of the thickness e1 of the reinforcement panel 30 and the excess thickness e2 generated by the compartments 5A, 5B and 5C on the surface of the sheet 1 forming the protection device 10. This obviously corresponds to a particular configuration of the invention. In the general case, it will be sufficient to choose the thickness e2 so that the addition of e1 and e2 is greater than or equal to the height H.

With reference to Figures 4 and 5 , we will now describe in more detail the implementation of the device of the invention in a bag generally used to transport liquid or quasi-liquid substances. The bags of this type are loaded by means of a forklift truck, the arms of the carriage being engaged inside hollow tubes arranged on the top of the bag. On the figure 4 , the bag 20 is in a substantially cubic form, which is in no way limiting. The four upper corners of the bag 20 are provided with a lifting belt 21, so that the bag as a whole is perfectly symmetrical. The bag 20 is also provided with connections made with a piece of cloth 22 sewn on each of two belts 21 forming a pair. The piece of cloth 22 thus forms, with the two lifting belts 21 of the same pair a tube or conduit intended to allow the engagement of the arms of the fork of a forklift. Furthermore, it is intended to equip at least one of the lateral sides of the bag 20 with a carrying handle 23 so as to be able to move it more easily when it is empty.

It is observed that the sides of the bag are made in a double fabric. This double fabric can be made either by joining two simple linen coupons, or by using a tubular fabric folded in two, forming a flattened sock. This double fabric thus defines an outer envelope 24 and an inner envelope 25 for the bag 20. The double fabric is divided into three housings, this by the production of two vertical seams 26, which run over the entire height of the bag. Within the three housings thus formed, reinforcing panels 30, 31 and 32 are introduced. In the embodiment shown, the central housing is larger than the two lateral housings. The width of the central reinforcing panel 30 is approximately 30% larger than the width of the two side panels, the height of the three plates being of course the same.

On the figure 4 the drain valve 27 is seen protruding from the inner casing 25. A flap 28 cut in the outer casing 24 allows access to said valve 27 from the outside.

As shown on the figure 5 , the panel 30 provided with the protection device 10 completely covers the area of the bag 20 surrounding the drain valve 27 so as to protect it from shocks due to transport. In the configuration shown, the reinforcement panel 30 is arranged in such a way that the closed compartments of the protection device 10 are oriented towards the outside of the bag 20. It is nevertheless conceivable to arrange it in the other direction so as to that the closed compartments are oriented towards the inside of the bag 20.

In practice, before filling the bag with liquid or quasi-liquid substances, it will be ensured that the drain valve welded to the sealed inner envelope of the bag is correctly inserted through the respective openings of the reinforcement panel and the protection device. This precaution will prevent the valve is positioned at an angle to the axis of said openings, which would subject the valve to significant shear forces during handling of the bag and therefore to a potential risk of rupture of said valve . Furthermore, it is also possible that, when filling the bag, there is a rectractation of the valve inside the bag, the valve is not maintained at the openings. In this case, the risk is high that the valve is positioned offset from the axis of said openings and is subsequently compressed between the inner envelope of the bag and the adjacent reinforcing panel. To solve this problem, it will be advantageous to equip the free end of the valve with a projecting annular edge and to arrange on the valve, in particular by clipping, in an intermediate position between the aforementioned annular edge and the protective device. , a stop plate having a semi-circular cutout whose diameter is substantially equal to the diameter of the valve. Thus, it will be avoided that the valve is positioned back from the plane defined by the reinforcing panel during filling of the bag.

Claims (8)

1. Bag (20) designed for transporting and handling liquid or quasiliquid substances, said bag comprising an outer envelope (24) and an inner envelope (25), an emptying valve (27) forming a protuberance with respect to one of its sides and secured to the inner envelope (25), and a reinforcing panel (30) at least partially covering said side, characterized in that a lower end of said reinforcing panel (30) is covered with a protection device (10) so as to protect the emptying valve (27) from transport-induced impacts, said device (10) being formed from a sheet (1) of flexible material which is folded back on itself, two parallel side edges of said sheet being fixed to one another over at least part of their length so as to form a substantially rectangular envelope which is open on only one of its sides, called the filling side, and into which said reinforcing panel (30) is inserted, said panel (30) having a thickness e1 and being provided with a hole (T) through which said emptying valve (27) can pass, the envelope having at least one opening (4) on its front and/or back face through which the emptying valve (27) can pass and at least one or more closed compartments (5A, 5B, 5C) containing flexible material, which compartments are located on the surface of the envelope and have a thickness e2 that is chosen such that the sum of e1 and e2 is essentially equal to or greater than the height H of the emptying valve (27), said one or more closed compartments (5A, 5B, 5C) being arranged around said opening (4).
2. Bag (20) according to Claim 1, characterized in that the flexible material contained in the one or more closed compartments (5A, 5B, 5C) of the envelope is identical to the flexible material used for forming the sheet (1) defining the envelope.
3. Bag (20) according to either one of the preceding claims, characterized in that the sheet (1) defining the envelope is made of polypropylene.
4. Bag (20) according to any one of the preceding claims, characterized in that the sheet (1) defining the envelope is itself formed by folding back on itself a base sheet made of flexible material, whose edges have been fixed together, in particular by welding.
5. Bag (20) according to any one of the preceding claims, characterized in that the envelope comprises exactly three rectangular closed compartments (5A, 5B, 5C) which are arranged so as to form an additional compartment (5D) in the envelope, said additional compartment (5D) being square and having, in its centre, the opening (4) through which the emptying valve (27) can pass.
6. Bag (20) according to any one of the preceding claims, characterized in that the sides of the envelope, with the exception of the filling side, are formed by welding the side edges of the sheet (1) defining the envelope.
7. Bag (20) according to any one of the preceding claims, characterized in that the device (10) for protecting the emptying valve (27) is arranged such that the closed compartments (5A, 5B, 5C) of the envelope are oriented towards the outside of the bag.
8. Bag (20) according to any one of Claims 1 to 6, characterized in that the device (10) for protecting the emptying valve (27) is arranged such that the closed compartments (5A, 5B, 5C) of the envelope are oriented towards the inside of the bag.

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