EP0743258B1 - Bulk product packaging tube, installation and process for forming such tubes - Google Patents

Abstract

The semi-rigid transparent or translucent plastics packaging tube (1) has one previously flattened end (11) sealed by two consecutive folds (13,14). The other tube end (10) is sealed by a base (5) in the shape of a disc glued or crimped onto the tube. The flattened end which is sealed by two folds has a band or label stuck on its two surfaces. The flattened end also has a cut out forming a slot allowing the tube to be suspended. The label is provided with perforations facilitating its tearing.

Description

Subject of the invention.

The present invention relates to tubes, preferably transparent or translucent, intended in particular for packaging bulk products. Examples of bulk products include confectionery such as candy, spices, hardware such as nails and screws, pharmaceuticals, haberdashery such as buttons, etc. This list is not exhaustive and many other products can be packaged by such a tube.

The present invention extends to an installation and to a process allowing the shaping of such tubes in a largely automated manner, and possibly of packaging in bulk products in line so as to obtain packaged products ready for sale.

Technological background underlying the invention.

The packaging for the sale of different products implies a certain number of specific requirements resulting in particular from modern sales techniques involving the use of display type displays.

In addition to the need for rapid and largely automated packaging techniques, a careful presentation of the packaging must be obtained, preferably so that the product it contains is visible by transparency. To meet the requirements of distributors, it is also necessary that the wrapped object can be easily placed at the points of sale and be easily accessible to buyers. For reasons of safety, hygiene and conservation, it is also advisable that the packaging is airtight and can be sealed, for example by a tear-off security strip and that it is sufficiently resistant.

Other conventional constraints such as the production price, compliance with packaging regulations, in particular the packaging of food products and in particular the packaging of products intended for children, etc., are added to the requirements it must be respected.

State of the art on which the present invention is based.

Many types of packaging have of course already been proposed, in particular in rigid or semi-rigid plastic.

Particularly known from document US-A-2584095 are semi-rigid tubes, made of thermoplastic materials, which are closed at their two ends by plugs generally in the form of elements in the form of cups or discs.

Tubes produced in this way are not particularly suitable for presentation for sale in suspended form in display type displays.

GB-A-1 267 815 describes packaging pinch seals obtained from a synthetic thermoplastic material. The document describes a technique for producing an airtight package which comprises a tubular body and a bottom produced in a single step by a blow molding technique.

The opposite end is flattened and forms a pinch-sealed end. This end is sealed (column 2, lines 45 and following) by electronic welding or using heated plates. The packaging is opened by cutting a corner from the upper end.

It is not intended that this opening can be opened and closed several times.

In US-A-3,026,016, a packaging bag which aims to combine the visibility characteristics of a transparent bag and the rigidity of a box.

The packaging consists of a semi-rigid back made of cardboard, plastic or another suitable material, covered by a sheet of flexible transparent plastic, for example cellophane, "Pliofilm", polyethylene or any other material which covers the front face. from the back, leaving an opening for the introduction of the goods to be packaged.

The packaging is supplied flat but can be unfolded to take the form of a box, especially if you want to pack relatively large items.

Such an article can be formed so that the front sheet completely covers the back but, in a preferred form, the back protrudes from the front cover sheet and constitutes a "head" provided with a perforation by which the packaging can be suspended .

According to one embodiment shown, the upper part of the packaging can be its open upper part folded back on itself, forming one or two folds and be stapled or otherwise immobilized in the folded state in order to '' seal the packaging.

Such packaging made of two different materials is not intended to be opened and then sealed.

Document FR-A-980 345 discloses a collapsible packaging for pasty products such as toothpaste made of so-called plastic materials such as aceto-cellulose sheets and the like.

They consist of two half-shells which are joined either hot, or using varnish or an appropriate solvent.

The part opposite to that used in normal use for evacuation of the product, provision is made according to one of the variant embodiments, to produce a permanent closure by embossing the flat faces of the zigzag ends, the bonding being made hot or cold by applying the embossed ends one on the other.

This embodiment therefore necessarily involves permanent bonding and is not intended to allow successive openings and closings of this end.

Document US-A-3065898 also relates to a collapsible tube for materials of the same type, in particular toothpaste.

This tube can be made, among other things, of plastic material and the closure, as in the previous case, is carried out at the end opposite to that provided for the exit of the product by bending the end of the tube in a zigzag. Again, this closure is not provided for successive openings and closings.

Aims of the present invention.

The invention essentially aims to meet the requirements described in the technological background mentioned above and to avoid the drawbacks of the solutions of the aforementioned prior art.

The aim is in particular to provide a packaging which is easy to shape, to fill with the product to be packaged, and to be closed, which is in a form which can be easily hung. The aim is also to produce an installation and a method making it possible to easily shape this type of packaging and making it possible in the installation to integrate the filling of the product to be packaged.

Characteristic elements of the present invention.

The semi-rigid packaging tube according to the invention is made of a thermoplastic material, preferably transparent or translucent.

The term "semi-rigid packaging tube" applies to a tube, well known in the packaging sector, and illustrated by the aforementioned document US-A-2584095, as opposed to packaging bags made of flexible plastic sheets and moreover generally containing plasticizers.

The term "semi-rigid tube" implies that the tube, consisting of a sheet wound in a cylinder and glued or welded to form a tube, if it is placed on its base, remains rigid without sagging like a sachet would . It is therefore appropriate that the material, without being completely rigid in itself, be flexible enough to wind, but also that its nature and its thickness allow it to offer a certain resistance to deformation in the tubular state, which will be used to achieve the filling according to the invention.

This tube is characterized in that at least one end of the tube is closed by at least two consecutive folds of opposite directions, made permanent by hot crushing, applied to this previously flattened end.

The tube is preferably closed in a conventional manner at the other end by a bottom element, which preferably has the shape of a cup and which is glued, crimped or otherwise fixed in or on the tube. In particular, the bottom can be fixed by heat sealing using a suitable tool creating a striated marking on the bottom.

It is also possible however, if it is desired that the two ends are each closed in the characteristic manner of the invention by two consecutive permanent folds of opposite direction, applied to the two ends also previously flattened.

In order to seal inviolably the end closed by at least two permanent folds, at least one label is advantageously glued on this end, preferably on the two faces of the end, after having compressed the folds.

One of the flattened ends is preferably provided with a cutout providing a light allowing the tube to be suspended, for example in a sales display type display. This cutting is preferably carried out after application of the sealing label.

In order to facilitate the opening of the tube by the purchaser, the label can be provided with perforations facilitating its tearing at the level of the underlying folds of the flattened end of the tube.

Other characteristic elements and advantages of the invention both with regard to the packaging tube itself and with regard to the installation and the process for its shaping, will appear on reading the description which follows, of the appended drawings. to the present application and in particular to the claims.

Brief description of the drawings.

Figure 1

represents in a perspective view a tube, one end of which is closed in a conventional manner by a glued or crimped bottom and for which the other end was produced according to the invention;

Figure 2

shows a front view corresponding to Figure 1;

Figure 3

shows a side view of the tube of Figures 1 and 2;

Figure 4

shows an enlarged view of the end of the flattened tube before folding;

Figure 5

shows the same end of the tube as Figure 4 in the flattened state after folding and provided with a sealing label affixed after crushing said folds;

Figure 6

represents the diagram of an installation, illustrating the process of the invention, which is suitable for the shaping of the tubes according to the invention, the conditioning of the bulk products to be packaged and the final shaping operations including labeling and cutting of the light.

Identical reference marks are used in the different figures for identical or similar elements.

The invention will be described in more detail with reference to the accompanying drawings by way of illustration without limiting the nature of a preferred embodiment of the invention for a tube, and for a tube shaping and packaging installation. a product, implementing the method of the invention.

Description of preferred embodiments of the invention.

The semi-rigid transparent packaging tube 1 is constituted by a body of generally cylindrical shape 3, closed at its lower end 10 by a circular bottom 5 which can for example be glued and / or crimped in or on the circular body 3. In the figures the bottom is shown convex but a flat bottom is obviously possible.

The tube 1 is filled to the appropriate level with a loose product such as candy (not shown), however, leaving a free upper space allowing the end opposite to that provided with the bottom 5 to be closed, as will be described below.

This filling is carried out as follows:

The end of the tube 1 is flattened by hot pressing. The end 11 which undergoes this crushing, as it appears in FIG. 2, is, in the front view, of width greater than the diameter of the rest of the body 3 because of the deformation undergone. The operating conditions (essentially the temperature and the pressure) are chosen so that the flattening is permanent, but without making the two faces applied one on the other. It remains possible to open the tube by spreading the "lips" created by the flattening and the tube, at this stage, is not perfectly tight, the simple flattening not allowing such a tightness to be achieved.

On this flattened end 11, two consecutive permanent folds of opposite directions 13 and 14 are produced, that is to say in a zigzag shape, which makes the tube watertight without bonding.

This fold is a thermoplastic, that is to say the application of pressure combined with the application of heat, so that each fold is permanent, that is to say that a fold is formed which, without causing the opposite faces of the flattened end of the tube to stick together, is such that the user, to open the packaging, must unfold the upper part of the tube, for example by forcing with his fingers on the end opposite the end of the bottom in the direction of the arrows 4 (Figure 2), to restore roughly to this end its initial tubular shape.

When the unfolding constraint is released, however, because of the permanent nature of the fold and the nature of the plastic material used, the folds resume their zigzag position and allow the closure of the packaging, restoring its waterproof character.

The plastic, that is to say a synthetic resin, makes it possible to produce a semi-rigid but also thermoplastic tube, that is to say that it deforms hot and under pressure while keeping after cooling, in the absence of the aforementioned opening constraint, the form in which it was thermoplastic. PET and PVC constitute basic materials suitable for producing the tube according to the present invention. These materials are used in suitable form with usual additives and adjuvants (dyes, stabilizers, etc.) and are formed by winding and gluing or welding in tubes according to well-known conventional techniques with appropriate wall dimensions and thicknesses.

It should be noted that it is also possible to carry out the filling after thermoforming, by opening the flattened end and provided with at least two plies, but that this technique is better suited for manual filling of prepared tubes than for integration into a continuous installation of online packaging.

A tube formed according to the invention has an excellent seal and tests have been carried out which indicate that it remains sealed up to pressures of 3.2 bars and up to 0.6 bar after spontaneous opening and reclosing.

According to a preferred embodiment of the invention, however, an adhesive strip or label 19 is applied to the flattened end 11 and provided with folds 13 and 14, preferably covering the two faces of the flattened end of the tube d 'a continuous strip and keeping the folds crushed. A perforation 20 can be provided to allow the tube to be hung in a display.

To facilitate opening of the tube by pulling on the end of the strip 19 covering said end, this strip is advantageously provided with perforations 23 on the front face (shown in dotted lines) and 24 on the rear face (shown in center lines), preferably at the height of the folds 13 and 14 that this strip 19 covers to allow easy tearing thereof and unfolding.

A suitable conditioning installation will be described with reference to Figure 6.

In a first station 51, the tubes are filled with a bottom at their base and open at the top with the products to be packaged, leaving sufficient upper space for the operations which will follow.

At station 53, forming is carried out (the tube being shown both from the front and from the side in the diagram) by first flattening the upper end of the tube when hot and then making the two zigzag folds. In order to make this deformation permanent, one proceeds to station 55 with a hot crushing.

At post 57, the “flap” produced by the two permanent pleats is labeled by affixing a label preferably perforated in concordance, that is to say overlapping, of the perforation zones with the permanent pleats. This label advantageously includes a barcode and all other useful information, such as a brand, price, description of the content.

Step 59 consists of an optical verification of the readability of the barcode with evacuation, if necessary, of non-conforming products.

At post 61, a light is cut out through the flattened part of the tube, in this case its upper part provided with two permanent folds and possibly through the label so as to allow the product packaged on a display rod.

The station 63 makes it possible to carry out a control of the possible presence of a metal, and in the event of positive response, involves the evacuation of the product of the line.

Item 65 allows the various products to be grouped together and overpacked or placed in trays or cartons.

It should be understood that this constitutes a diagram of an embodiment according to the invention, and that other variants are possible, and in particular the insertion into the chain of other stations allowing for example other technical operations such than affixing an additional label.

The stations 53, 55 and 57 can in particular be modified, to obtain, for example, a pre-folding using a folding tool which already presses the product hot to give it the shape of a staircase, this station being followed by a transfer to the next station during which the folding is refined using polished stainless steel guides until the next station obtains an almost definitive double zigzag fold, after which, by a final crushing of these folds, we get a flat product ready to be labeled.

With regard to the labeling operation, different operating techniques can be envisaged. The removal of the label can in particular be carried out as follows: the label is taken up by the vacuum at the output of the printer. It is then brought between two brushes, then brought into contact with the bent tube. Then, the two brushes move back to form a "U" with the label, then fold it back on the back of the product. The label is pressed again to perfect its aesthetics.

Alternatively, one or two labels can be affixed respectively on each of the faces of the tube.

As regards the cutting of the light provided at station 61, a double punching tool can be used, allowing an elliptical cutting of the top of the tube as well as that of the "Euro-hole" 20 for placing on the shelf.

Various techniques can be envisaged for the evacuation of the finished product; it is possible in particular to blow through the bottom of the product so as to eject it directly into a shipping carton. It is also possible to provide additional positions at this level, such as a conveyor belt at the machine outlet, to receive the discharged products.

Sorting stations for products by improper printing of the "barcode" are also possible at different levels from that indicated.

The detection of metal particles using an ultra-sensitive metal detector of the tunnel type placed on a belt conveyor is generally adopted.

It is also possible, for the product reception station, to provide for the presence of an operator, who receives the products at the end of the conveyor, puts them in trays, boxes or directly on a display stand.

Of course, conventional indexing techniques are used from station to station to ensure automated production and online integration of tube shaping and filling.

Production rates of around 3600 packaged products per hour can be easily reached.

The device can for example be provided for PVC tubes varying from 34 to 70 mm in diameter by changing the tooling, these tools being suitable for receiving tubes with a length of 210 to 410 mm open, which corresponds approximately to 180 to 380 mm closed.

All products not liable to damage the tube used can be treated in this way. The technique is however particularly recommendable for food products (sweets, spices, etc.) because of the tightness of the closure of the invention.

The tube is advantageously made of a sheet of calendered PVC, unplasticized and free of heavy metals (Sb, As, Ba, Cd, Cr, Pb, Hg) transparent, with a thickness of 175 to 250 micrometers, of the type 188 / 12 from the firm KLOECKNER PENTAPLAST (Montabaur - Germany) with a modulus of elasticity E (according to standard DIN 53457) from 1200 to 2000 Newton / mm ² , these values being of course by way of indication without limitation.

Although preferred embodiments of the invention have been described, it should be understood that numerous operating variants, both in terms of the production of the tube and of the shaping and packaging equipment described, are feasible. in the context of the invention. As mentioned previously, the two ends of the tube can be provided with the closure according to the technique of the invention (permanent zigzag folds)

The invention is in particular not limited to particular dimensions or precise embodiments of the apparatus described.

Claims (14)

1. Semi-rigid packaging tube, preferably transparent or translucent, made of a plastic material, characterized in that at least one end (11) of the said tube (1) is sealed by at least two consecutive permanent folds (13, 14) in the opposite direction, applied to this end (11) which has been previously flattened.
2. Packaging tube in accordance with claim 1, characterized in that the other end (10) of the said tube (1) is sealed by a lid (5) which is preferably in the form of a cup or disc and which is glued, crimped or fixed in another way in or on the tube.
3. Packaging tube in accordance with claim 1, characterized in that the two ends (10, 11) of the said tube (1) are each sealed by at least two consecutive permanent folds (13, 14) in the opposite direction, applied to the end (10, 11) which has been previously flattened.
4. Packaging tube in accordance with any of the previous claims, characterized in that the flattened end (11) sealed by at least two permanent folds is provided with at least one strip or a label (2) glued on this end (11), preferably on the two faces of the end (11), after having flattened and compressed the two folds (13, 14).
5. Packaging tube in accordance with any of the previous claims, characterized in that the flattened end (11) is provided with a cut (20) making a hole enabling the tube to be suspended.
6. Packaging tube in accordance with claim 4 or 5, characterized in that the label is provided with perforations (23, 24) making it easy to tear it at the folds (13, 14) underlying the flattened end (11) of the tube (1).
7. Installation for integrated forming of packaging tubes in accordance with any of the previous claims, characterized in that it comprises a forming station (53) where one end of the tube (1) is flattened by making at least two zigzag folds (13, 14) and a station (55) where this deformation is made permanent by hot flattening.
8. Installation in accordance with claim 7, characterized in that it comprises a station (57) in which labelling is carried out by affixing at least one label (2) which is preferably perforated, in coincidence with, i.e. by covering perforated areas (23, 24) with the permanent folds (13, 14).
9. Installation in accordance with claim 7 or 8, characterized in that it comprises a station (61) in which a hole is cut through the flattened part of the tube and possibly the label, to enable the packaged product to be suspended on a display stand rod.
10. Installation in accordance with any of claims 7 to 9, characterized in that it comprises a station (51) for filling the tube before it is formed.
11. Installation in accordance with any of claims 7 to 10, characterized in that it comprises one or more control stations (59, 63).
12. Integrated process for forming packaging tubes in accordance with any of claims 1 to 6, characterized in that one end of the tube (1) is flattened by making at least two zigzag folds (13, 14) and that this deformation is made permanent by hot flattening.
13. Process in accordance with claim 12, characterized in that after the said hot flattening, filling of the product to be packaged is carried out and labeling by affixing at least one label (19), which is preferably perforated, in coincidence with, i.e. by covering the perforated areas (23, 24) with the permanent folds (13, 14).
14. Process in accordance with claim 12 or 13, characterized in that a hole (20) is cut through the flattened part of the tube and possibly the label, to enable the packaged product to be suspended on a display stand rod.

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