EP0585908A2 - Container with insertable bag - Google Patents

Abstract

The invention relates to a storage-bag container, to an assembly unit therefor and to the manufacture thereof. In this case, a flexible storage-bag container is inserted into a standardised commercially available external container for pressure cans. The flexible material of the internal, collapsible bag is welded directly on to the outer wall of an immersion tube. The seams are located at the point where the immersion tube is connected to the valve body. This point is a constituent of the valve body and has at the lower end an annularly outwardly projecting shoulder over which one end of the immersion tube can be fitted. The point located directly above the shoulder is not welded to the collapsible bag. It is ensured, on the one hand, by the arrangement of the seams and, on the other hand, by the connection of the immersion tube to the valve body that the collapsible bag cannot become detached from the immersion tube. The adherence of the tube to the valve body by means of friction forces prevents the tube from slipping off the valve body while the bag is being filled and in the drop test during the quality control. The main advantages of this invention are greater freedom in design, low costs and a simpler manner of manufacture, above all because no special connection pieces, container components or epoxy resins are required. <IMAGE>

Description

The present invention relates to barrier bag containers for storing and dispensing a filling material and to a method for producing the same.

Barrier bag containers with a double chamber system are generally known, but are not yet widespread.

This type of container contains an inner, compressible container or collapsible bag, which is surrounded by an outer, solid container or jacket. This creates two independent chambers; one inside the compressible inner bag and the other between the outer jacket and the inner bag. A closure in the form of a valve or dispenser is placed over the outer casing in such a way that the outer edge of the closure surrounds the upper part of the outer casing and hermetically seals it. The valve is connected to the inner, compressible bag so that only the contents of the same can be released to the environment. The propellant gas therefore does not come into contact with the contents of the inner, collapsible bag, since this is enclosed in the chamber separated from the outer jacket and the inner bag.

A burden on the environment, which can result from the fact that propellant leaves the bag together with the product, is prevented by the fact that the propellant remains in the container in the sealing bag cans. The known barrier bag containers have a relatively complicated structure and are expensive to produce because special container components and apparatus are required for this.

The inner, compressible bag in the well-known double chamber containers is made of a solid but very supple material. Soft aluminum foils, pliable plastic material or laminated foils such as polyolefins, aluminum foils, nylon and are suitable for this Polyester, which are connected to each other so that a coated or laminated film is formed. The material of the inner, compressible bag must be of good quality so that no diffusion and thus mixing of product and blowing agent can occur.

One problem with the manufacture of barrier bag containers is the hermetic fixation of the inner, compressible bag to the material of the valve body. There must be no leakage of product and propellant from the two separate chambers. The solution to this problem is made difficult by the requirements for the inner, collapsible bag. The inner compressible bag must not become detached due to the pressure created during filling and during the drop tests during quality control.

In a known can of this type, the inner, compressible bag consists of a multilayer laminate which is welded directly to the valve body and which special valve body is made of polyethylene. This material allows the collapsible bag to be welded to the valve body. However, most standardized and commercially available valve bodies for the containers have a valve body made of nylon, while the inner, compressible bag is made of polyolefins or contains polyolefins. So that the collapsible bag can still be welded directly to the valve body, a special valve body is required which is made of a different material than conventional nylon; eg from polyolefins, as already mentioned above. In this form, the inner, compressible bag can be easily welded to the valve body.

The disadvantage of using polyolefins as valve material is that the resistance of polyolefins to gases is lower than that of conventional nylon. This disadvantage is compensated for by the fact that epoxy resin is used in the barrier bag containers described above, with which the valve is covered and sealed after being welded to the compressible bag. This additional operation complicates the manufacturing process and increases the cost of the container. It is therefore proposed that the inner, compressible bag within the container is attached to the valve by using a special connector (immersion tube) in such a way that the immersion tube on the one hand with the collapsible bag and on the other hand with a specially designed valve configuration e.g. according to U.S. Patent No. 3,342,377 and No. 4,969,577.

The conditions associated with a special valve configuration, the immersion tube and special valve material in these known barrier bag containers are disadvantageous because they reduce the design freedom and no longer permit the use of standardized, commercially available container components (valve). There is therefore a need for improved, inexpensive barrier bag containers and for manufacturing processes therefor, which allow great freedom of design for various possible uses. Simplified production is also desired and the advantage of lower costs when using valves and connecting pieces from the rod should be perceived.

The present invention is to provide an improved barrier bag container which overcomes the problems of the conventional barrier bag container described above compensates or overcomes. A special characteristic of the present invention consists in the composition and the method for producing a novel barrier bag container, which allows greater freedom of design for the various possible uses. Another characteristic of the invention lies in the simplification in the manufacture and in the use of cheap, standardized, commercially available valves with immersion tubes. There is no need for any special valve configurations or materials, as they were previously used for the production of barrier bag containers.

These and still other advantageous properties are achieved by the barrier bag container on which the invention is based, for storing and dispensing a filling material. The container contains an outer jacket and a valve which is attached to the outer jacket of the container. The valve of the dispenser contains a manually operable valve button, which can release the product in the bag when actuated. An inner, compressible bag is placed within the barrier bag container which contains the product to be released. An immersion tube is placed over an annular cone on the valve body and is thereby secured. The immersion tube is located inside the collapsible pouch so that the product can be released in the pouch via the immersion tube and valve. The inner, compressible bag is attached to the upper part of the immersion tube, which in turn is placed over an annular, cone-like projection, which is located on the valve body.

Surprisingly, it has been found that the collapsible is easier and less problematic Attach the bag directly to the outer top of the relatively thin dip tube, rather than to a specially designed connector or directly to the valve. The attachment is preferably carried out by welding. When attaching the weld seams at the point where the immersion tube is placed over the annular projection of the valve body, no special welding spindle or welding cores are required to support the interior of the immersion tube during welding, since this function is achieved by the stable, annular cone of the valve is guaranteed, over which the immersion tube is put. With the device and the method according to the invention, fewer rejects are produced and higher production is made possible. In addition, when the bag is sealed with a standardized immersion tube, commercial valves can be used which show a higher degree of flexibility and are also more user-friendly. It also reduces the cost of off-the-shelf valve use and eliminates the need for complex connectors, special valve configurations, and materials that were previously used in the manufacture of barrier bag containers.

Another feature of the barrier bag container according to the invention is that the immersion tube must be firmly connected to the valve before welding, ie one end of the immersion tube is put over the annular cone of the valve. The flexible material of the compressible bag is then welded to the part of the immersion tube which has been put over this annular projection of the valve body. For this purpose, two vertically opposite welding blocks are used, which can clamp the bag, the immersion tube and the valve cone exactly.

The underside of the valve with the annular projection already discussed ultimately serves to support the one end of the immersion tube against the pressure of the welding blocks and to achieve problem-free and accurate welding with the supple material of the bag.

The part of the valve over which the immersion tube is placed has an annular shoulder that forms a kind of cone. Slipping the immersion tube over the cone guarantees a tight fit, so that even when the collapsible container is filled under pressure, the valve and tube are not released. When welding, the place where the immersion tube with the collapsible container lies above the conical part is kept free, i.e. no weld seam is created because the cone could be damaged by the heat and the tube on it could melt, which would lead to a loss of elasticity. Otherwise there would be a risk that the immersion tube with the welded-on bag could become detached from the valve when filling the container or during drop tests in quality control. It is therefore necessary according to the invention that the inner, compressible bag is only welded to the immersion tube above and below the annular cone and axially to the same. No weld seam is therefore made directly above the annular cone.

The valve and the immersion tube in the arrangement described are standardized and all components are commercially available. The use of special connectors and valve configurations for attaching the collapsible bag to the barrier bag container can be avoided, as already said, and the use of special material for the construction of the valves is also unnecessary. The standardized and in the trade Available immersion tubes are made of polyethylene or polypropylene and the inner, compressible bag generally consists of polyethylene, polypropylene or a laminate of polyethylene and polypropylene. Standard nylon valves can therefore be used without the risk of incompatibility because the connection between the valve and the immersion tube is not welded. The fixed connection between the immersion tube and the valve body is based only on frictional forces, so welding of the two parts is not necessary.

In the container according to the invention there is a compressed gas between the outer jacket and the inner, compressible bag, which acts on the product in the collapsible bag. This pressure expels the product from the bag after the valve button has been actuated. Such a valve is preferably used, which allows the continuous and very quick filling of a product into the bag after the completion of the container. The blowing agent is introduced into the container under pressure during production. The method according to the invention for producing a barrier bag container for storing and dispensing a product is defined in the claims and includes in particular the following elements: a valve body; an immersion tube, one end of which is slipped over an annular cone on the underside of the valve body; a compressible bag that is welded to the outer wall of the immersion tube immediately above and below the ring-shaped cone and the assembly of this unit - consisting of the bag, the immersion tube and the valve body - on the outer jacket of the container.

The unit, consisting of the valve body, immersion tube and the collapsible bag, can be manufactured according to the invention depending on the application and can be delivered to the convection or to the bottling plant as a separate assembly unit. When filling, the assembly unit is put together with the outer jacket, the immersion tube with the bag being located inside the outer jacket.

During assembly of the assembly unit with the outer jacket of the container, compressed gas is simultaneously filled into the chamber between the outer jacket and the collapsible bag. Then the valve also presses the contents into the compressible bag.

• Figur 1 zeigt einen vergrösserten Querschnitt eines standardisierten und im Handel erhältlichen Druckventils;
• Figur 2 zeigt die Vorderansicht eines standardisierten Eintauchröhrchens in dessen Wand kleine Öffnungen angebracht sind, die den Fluss des Produktes durch das Röhrchen während der Füllung und Abgabe erleichtern;
• Figur 3 zeigt einen Querschnitt nach der Montage des Ventils aus Fig. 1 und dem Eintauchröhrchen aus Fig. 2 in Originalgrösse;
• Figur 4 zeigt eine Vorderansicht, z.T. als Querschnitt mit einem über den unteren Teil des Ventilkörpers gestülpten Eintauchröhrchen, mit verschweisstem kollabierbaren Beutel;
• Figur 5 ist eine Aufsicht der Baugruppe aus Fig. 4;
• Figur 6 ist eine vergrösserte Darstellung des oberen Teils aus Fig. 4, wobei das flexible Material des kollabierbaren Beutels mit der Aussenwand des Eintauchröhrchens verschweisst ist und dieses über den ringförmigen Konus am Ventilkörper, gestülpt ist und wobei im Bereich des Konus keine Schweissnaht angebracht ist;
• Figur 7 zeigt einen Querschnitt durch einen vollständigen Sperrbeutel-Behälter;
• Figur 8 zeigt eine schematische Darstellung mit den beiden Schweissblöcken und der erfindungsgemässen Montageeinheit;
• Figur 9 ist eine Vorderansicht der Arbeitseinheit des unteren Schweissblocks entlang der Linie IX - IX, gemäss Fig. 8;
• Figur 10 ist die rechte Seitenansicht des Schweissblocks, gemäss Fig. 9;
• Figur 11 ist eine vergrösserte Ansicht des Schweissblocks aus Fig. 9 mit den Vertiefungen für denjenigen Teil der Montageeinheit, die verschweisst werden muss;
• Figur 12 zeigt eine vergrösserte Aufsicht auf den Schweissblock, gemäss Fig. 11.

These and other properties, features and advantages of the invention described above are explained in more detail with reference to the following figures. The figures are for illustration only and show an embodiment in accordance with the present invention.

• Figure 1 shows an enlarged cross section of a standardized and commercially available pressure valve;
• Figure 2 shows the front view of a standardized immersion tube in the wall of which there are small openings which facilitate the flow of the product through the tube during filling and dispensing;
• FIG. 3 shows a cross section after assembly of the valve from FIG. 1 and the immersion tube from FIG. 2 in the original size;
• FIG. 4 shows a front view, partly as a cross section with an immersion tube placed over the lower part of the valve body, with a welded collapsible bag;
• Figure 5 is a top view of the assembly of Figure 4;
• Figure 6 is an enlarged view of the upper part of Figure 4, wherein the flexible material of the collapsible bag is welded to the outer wall of the immersion tube and this is put over the annular cone on the valve body, and wherein no weld seam is attached in the region of the cone;
• FIG. 7 shows a cross section through a complete barrier bag container;
• FIG. 8 shows a schematic illustration with the two welding blocks and the assembly unit according to the invention;
• FIG. 9 is a front view of the working unit of the lower welding block along the line IX-IX, according to FIG. 8;
• Figure 10 is the right side view of the welding block, according to Fig. 9;
• FIG. 11 is an enlarged view of the welding block from FIG. 9 with the depressions for that part of the assembly unit which has to be welded;
• FIG. 12 shows an enlarged top view of the welding block, according to FIG. 11.

A double-chamber barrier bag container 1, as disclosed with the present invention, is shown in FIG. The container 1 has two chambers. The chamber 2 contains a viscous product and the chamber 3 contains a compressed propellant. The chamber 2 is located inside the bag 4, which is located inside the container 5 of the can 1. The second chamber 3, which is reserved for the propellant gas, is formed by the space between the outer jacket and the inner collapsible bag 4.

A valve body 6 is fastened to the outer jacket of the container 5 and closes the upper opening thereof. The valve body is connected to the container 5 by fastening the outer edge of the valve body to the upper, open flange neck of the outer container, e.g. by clinching. The valve body contains a manually operated valve button 7, which releases the product in the compressible bag when actuated.

The valve body, without the push button, is shown in more detail in FIG. 1. The valve body is preferably a standardized and commercially available dispenser. The standard model of the riser tube 8 is outlined in FIG. 2. Three notches 9 are made at certain intervals along the outer wall of the tube 8. These holes serve to facilitate the flow of the product through the tube during filling and dispensing. As shown in FIG. 2, the immersion tube is open at the top and bottom. The upper end of the round immersion tube 8 is placed over the lower end 10 of the valve body 6. The frictional forces hold the tube firmly against the valve body. The composition of the dispenser with the immersion tube is outlined in FIG. 3. An annular, outwardly projecting shoulder 11 is attached to the lower end of the valve body 6. When the upper part of the immersion tube is put over the lower end 10 of the valve body 6, the shoulder or the annular cone is stretched and stretched the tube at this point, so that it can only be pulled over the cone with great force.

The immersion tube secured by the attachment 10 of the valve body 6 is firmly connected to the collapsible bag 4. More specifically, the inner compressible bag 4 consists of two opposing layers 12 and 13 of pliable material which have been welded together along their peripheries 14. The bag is then welded to the outer wall of the immersion tube so that the tube is completely inside the bag. The weld seams are made at the point where the immersion tube is placed over the ring-shaped attachment of the valve body. The flexible material of the collapsible bag consists of a laminate that consists of layers from the outside in, e.g. can be constructed from polyester, aluminum foils, nylon and low density polyethylene. The individual layers in the laminate are adhesively bonded to one another, and the laminate has a thickness of approximately 134 μm. The standard immersion tube 8 is e.g. made of polyethylene. This ensures that it can be sealed with the low density polyethylene bag.

The assembly unit 15, consisting of the collapsible bag 4, the immersion tube 8 and the valve body 6 according to FIGS. 4 to 6, is produced according to the invention by means of two vertically opposite welding blocks 16 and 17 (FIG. 8). The welding blocks 16 and 17 can be displaced relative to one another in the direction of arrow A, so that the two sides of the blocks can press the layers of fexible material 12 and 13 to be melted against one another or can be connected to the immersion tube 8 in a sandwich-like manner. Under pressure and with the application of heat, above the melting point of polyethylene, the two opposite layers are welded to each other as well as to the part of the outer wall of the immersion tube which has been put over the annular cone of the valve body.

A semicircular recess 18 is made in each of the two welding blocks so that the assembly unit 15 - consisting of the bag, the tube and the annular support of the valve body - fits exactly. Each of the two semicircular depressions 18 has a further semicircular depression 19 in the axial extent, into which the annularly projecting shoulder 11 of the valve stub and the immersion tube 8 lying above it and the layers 12 and 13 fit exactly. At this point, however, there is no welding, ie the area in the immediate vicinity of the shoulder or the annular cone remains cold. The cone 11 is thus not damaged during the welding process and the part of the immersion tube which is located directly above the cone does not melt. Therefore, the tube does not lose its elasticity at the point mentioned. When filling the container or during drop tests during quality control, the frictional forces between the annular cone and the immersion tube prevent the tube with the collapsible bag from detaching from the valve body. The semicircular depression 20 in each of the welding blocks 16 and 17 is intended so that the materials of the two flexible layers 12 and 13 can be exactly matched to one another by movement during the welding process. The flexible material of the two opposite layers 12 and 13 is welded to the outer wall of the immersion tube, with two weld seams above and below the annular shoulder 11. The location in the immediate vicinity of the annular cone 11 remains free.

After the welding process, the finished assembly unit 15 is inserted into the opening at the upper end of the outer jacket 5. The container casing is made of metal in the illustration described, but other materials such as plastic or glass can also be used, provided that the casing maintains its necessary strength against the compressed gas in the outer chamber. Before the edge of the valve body 6 is clinched with the outer casing 5 of the can, the propellant gas must be filled into the outer chamber 3 under pressure. The edge of the valve body 6 is then clinched to the outer jacket 5 of the can. As a result, the opening at the upper end of the container 5 and thus the chamber 3 is hermetically sealed. A liquid product which is stored in the bag 4 and is to be dispensed in a metered manner is pressed into the collapsible bag 4 by the valve body 6.

With the features and method steps described, no special spindle is additionally required for the interior of the immersion tube during the welding process, since a corresponding supporting effect is heard by the valve body. The supple material of the inner, compressible bag 4 is attached to the immersion tube in such a way that the propellant gas and the filling material cannot pass into the other chamber of the container. Furthermore, the type of connection mentioned prevents the immersion tube from detaching from the valve together with the collapsible bag during the filling process or during drop tests during quality control. In addition, no special connectors or specially configured valves are required. By using standardized and commercially available valves with immersion tubes, the costs are reduced and the flexibility for the design of the container is increased. The Barrier bag container of the invention is also relatively easy to manufacture and no special epoxy resins are required to hermetically seal the container.

Further changes and modifications are in the area of professional trade. For example, the barrier bag container according to the invention is not only limited to a double-chamber system, but can also be used in multi-chamber systems with barrier bag containers with more than two chambers. Furthermore, the flexible material of the collapsible bag is not only limited to the specific laminate described, but also other laminates, e.g. Containing propylene can be used. Immersion tubes made of propylene can easily be used for the welding process. Non-laminated material is also suitable for the production of the collapsible bag. The same applies to the valve body. Thus, other forms can also be used, such as a pump spray dispenser together with a barrier bag container according to the present invention. In such a case, it is unnecessary to fill a propellant gas into the chamber 3 of the container.

Claims (12)

Barrier bag container for storing and dispensing a filling, comprising:
an outer container;
a dispensing valve mounted on this outer container with a manually operable valve button which can be pressed in for dispensing the filling material from the container;
a compressible inner container within the outer container for storing the contents;
and an immersion tube which is fastened at one end to the valve body and projects into the compressible inner container in order to supply filling material from the inner container to the dispensing valve when the dispensing valve is actuated,
which valve body has a lower part with a ring-shaped projecting shoulder, over which the immersion tube together with the collapsible inner container is placed and is thus firmly attached to the so-called valve body, thereby creating a firm connection between the valve body and the immersion tube with the collapsible inner container attached to it, which compressible inner container is attached directly next to the point on the immersion tube, where it is placed over the annular shoulder. Barrier bag container according to claim 1, characterized in that the collapsible container is welded to the outer wall of the immersion tube. Barrier bag container according to one of the preceding claims, characterized in that the immersion tube consists of polyethylene or polypropylene and that the collapsible container is made of polyethylene, polypropylene or a laminate which contains polyethylene or polypropylene. Barrier bag container according to one of the preceding claims, characterized in that the immersion tube has a circular cross-section and the collapsible container consists of two opposite layers made of a flexible material, which are welded on their outer edges and which are welded to the immersion tube at corresponding locations, so that this extends into the interior of the collapsible container. Assembly unit for producing a barrier bag container according to claim 1, comprising:
a dispensing valve with a valve cover and a manually operable valve button, which can be pressed in to dispense the filling material from the container;
a compressible inner container for storing the contents;
and an immersion tube which is fastened at one end to the valve body and projects into the compressible inner container in order to supply filling material from the inner container to the dispensing valve when the dispensing valve is actuated,
which valve body has a lower part with an annularly projecting shoulder, over which the immersion tube together with the collapsible inner container is placed and is thus firmly attached to the so-called valve body, thereby creating a firm connection between the valve body and the immersion tube with the collapsible inner container attached to it, which compressible inner container is attached directly next to the point on the immersion tube where it is connected to the valve body. Mounting unit according to claim 5, characterized in that the collapsible container is welded to the outer wall of the immersion tube. Assembly unit according to one of claims 5 and 6, characterized in that the immersion tube consists of polyethylene or polypropylene and that the collapsible container consists of polyethylene, polypropylene or a laminate which contains polyethylene or polypropylene. Mounting unit according to one of claims 5-7, characterized in that the immersion tube has a circular cross-section and the collapsible container consists of two opposite layers made of a flexible material, which are welded on their outer edges and which are welded to the immersion tube at corresponding points, so that this extends into the interior of the collapsible container. A method for producing a barrier bag container according to claim 1, wherein an immersion tube is placed over a shoulder-shaped projection of a valve body, then a collapsible bag is placed over the immersion tube so that it extends into the interior of the collapsible bag, this bag immediately next to it the place where the immersion tube is placed over the projection is attached to the outer surface of the immersion tube and finally the whole thing in an outer container is inserted and its opening is closed. A method according to claim 21, characterized in that the collapsible bag is welded directly next to the shoulder on the outer surface of the immersion tube, but not directly on the shoulder itself. A method for producing an assembly unit according to claim 5, wherein an immersion tube is slipped over a projection shoulder-shaped projection of a valve, then a collapsible bag is placed over the immersion tube so that it extends into the interior of the collapsible bag and this immediately next to the point , where the immersion tube is placed over the projection, is attached to the outer surface of the immersion tube. A method according to claim 11, characterized in that the collapsible bag is welded directly next to the shoulder on the outer surface of the immersion tube, but not directly on the shoulder itself.

Images