EP0752375B1 - Method and machine for providing a package made of a sheet of terable foil with an easy-to-open device - Google Patents

Description

The invention relates to the production of a device easy to open for packing objects or groups at least partially wrapped objects of tearable synthetic film. In particular, the invention relates to the packaging of everyday items such as the items offered for sale in large distribution areas (food products, books, cassettes, records, cigarettes, ...).

Many objects or groups of objects are at least partially wrapped in film enveloping, that is to say generally totally enveloping or sometimes only partially wrapping, synthetic packaging film or overpack which must be torn by the user. he may for example be a film of PVC, polyethylene, polypropylene ... In particular, among the films tear-off, we encounter packaging films of the type mono-oriented, and in particular heat shrinkable films placed around the object or group of objects by heat shrink, or films folded around the object or group of objects.

Packages known by film less partially enveloping with synthetic film tearable give satisfaction, but pose the problem of the subsequent opening of the packaging, in particular by the consumer.

In the case of synthetic films tearable, and more particularly in the case of films we have always given up now to make an incision or a perforation at through the film, for several reasons. All first, such a film is generally applied on contact narrow of the object or group of objects to be packaged. In consequence, not to attack or damage the object or group of objects, we consider it essential to make a possible incision or perforation before perform the heat shrinkage or application step close of the film on the object. However, during this application, in particular by heat shrinking, this results in either a prohibitive enlargement of the incision or perforation, either a tear in the film during the application. In addition, the fragility of such films is such that the presence of an incision or perforation could damage the packaging or to affect its resistance too considerably subsequent to handling.

We already know pre-packaged packaging incisions or perforations making primers of tears and / or precuts. However, these incisions or perforations, made before applying the packaging around the object or group of objects, are reserved for resistant packaging materials and the general dimensions are not changed when the application on the object or group of objects (side of cardboard, rigid molded plastic, film neither stretched nor heat shrunk and not tearable, ...). The manufacture of these packages require the processing of long lengths of film or cardboard, before the packing operation, to spare incisions or perforations. In addition, it is necessary to precisely position the incisions or perforations on the film or cardboard. The process is therefore little convenient and inflexible.

With tear-off type films, we have already thought of facilitating the opening by sparing for example a V cut at the periphery of a marginal strip of the film (packaging of coffee powder, leaves packaging for chocolate bars, ...). However, the cutout is not always visible, is not always sufficient to effectively initiate a tear, and is not applicable to packaging whose film does not have a marginal strip suitable for receive such a cutout. In the latter case, we usually incorporates a tear strip or bead between the object or group of objects to be wrapped and the film of film covering it. An extreme free portion of the tape or cord is accessible from the outside by the user (cigarette pack, cassette, book or disk...). Such a device is nevertheless delicate and expensive to make, and is reserved for objects or groups of generally simple and manufactured and packaged objects in very large series. In addition, depending on the nature of the film packaging used, the opening is not always convenient even with the aid of said strip or cord tear.

In other cases, the packaging under tear-off synthetic film has no particular easy opening device, so that the consumer is forced to use a cutting tool or sharp, risking injury or damage to the packaged product.

US-A-3,442,436 describes, in 1967, a process for forming means for easy opening of a shrink wrap film after or before heat shrink, in which a punch is brought and applied against the film to cut or burn it according to a broken cut line forming at least one triangle, the vertex of each triangle defining an end free and the base of each triangle being connected of the film, so that each triangle constitutes a leg can be pulled to open the film.

Then an application device label is brought to place a label above of the cut line. Despite the age of this document, the solution he advocates is not exploited because it poses many problems. First of all, it is not possible in practice to realize the broken cut-off line by applying a punch without damaging the product packed, except possibly entirely manually. In addition, if the cut is made before the film is laid around the product or before heat shrinking, this is distorts and causes deterioration of the film and packaging under the effect of the constraints applied during laying the film around the product, especially in the event of heat shrink. So it is not possible to realize in an industrial and automatic way, precisely, in series, and at a reasonable cost, the means of opening easy described in this document.

Likewise, FR-1 393 045 describes an easy opening device consisting of a strip of adhesive tape pressed onto a slot in the packaging, but do not offers no industrial process or machine allowing the realization of these measures.

The invention aims to overcome these disadvantages in proposing a process for equipping an object or group of objects packed under at least partially wrapping film tear-away synthetic - especially film heat-shrinkable- with an easy opening device, adaptable to any form or nature of object or group objects and films, and can be produced in a way industrial, automatically, in series, without deteriorating the wrapped object or group of objects.

The invention relates more particularly to propose such a method that can be implemented in continuous, in cadence, and while the objects or group objects are moving. The invention also aims to propose such a method that can be implemented on a compact automatic machine operating without interruption, in cadence, similar to a labeller automatic.

The invention also aims to provide a machine for implementing this process. The invention aims more particularly to propose such a machine compact that can operate at high speed, especially similar to an automatic labeller.

The invention also aims to provide a such a method for providing the packaging with a device easy to open that does not affect the qualities of the packaging thus produced, in particular from the point of view of airtightness, tightness, preservation of wrapped objects or groups of objects ...

The invention also aims to propose such a process that can be used with all kinds of objects, and especially with soft objects such as products food (portions of cheese, coffee, ...), or with hard objects (recorded magnetic tapes, discs, packets of cigarettes ...) without damaging or polluting Items.

To do this, the invention relates a process for provide a packaging with an easy opening device according to the invention, that is to say a method of installing a easy opening device at the end of a process packaging of an object or group of objects by said film.

The invention thus relates to a method according to claim 1.

Advantageously and according to the invention, it is install and orient the opening tab so that that the incision is closer to the common edge of the portion anchor and grip portion only from the edge opposite extreme of the anchor portion.

Advantageously and according to the invention, we train objects or groups of objects packed in continuous movement without interruption in translation according to a direction at least substantially perpendicular to the main direction of the incision to be made.

Advantageously and according to the invention, for make the incision, we use a rotary knife around of an axis at least substantially parallel to the direction of moving packed objects or groups of objects.

Advantageously and according to the invention, for make the incision, use a knife comprising a blade mounted on a mobile support defining a range of protection able to come into contact with the film for limit the penetration height of the blade through the film.

• des moyens d'entraínement et de guidage des objets ou groupes d'objets préalablement emballés par une pellicule de film synthétique au moins partiellement enveloppante, en déplacement continu de translation les uns à la suite des autres,
• un poste de découpe d'une incision en forme de portion de droite à travers la pellicule de chaque objet ou groupe d'objets,
• à l'aval de ce poste de découpe, un poste de pose d'une languette d'ouverture formée d'une étiquette comprenant une portion d'ancrage et une portion de préhension s'étendant en prolongement de la portion d'ancrage, ce poste de pose d'une languette d'ouverture comprenant des moyens automatiques de pose d'une étiquette sur la pellicule de chaque objet ou groupe d'objets avec la portion de préhension qui prolonge la portion d'ancrage dans une direction au moins sensiblement perpendiculaire à la direction de l'incision telle que ménagée par le poste de découpe d'une incision,
• des premiers moyens de détection de la présence d'un objet ou groupe d'objets emballés en regard du poste de découpe d'une incision,
• des seconds moyens de détection de la présence d'un objet ou groupe d'objets emballés en regard du poste de pose d'une languette d'ouverture,
• des moyens adaptés pour actionner le poste de découpe d'une incision lorsque les premiers moyens de détection détectent la présence d'un nouvel objet ou groupe d'objets,
• des moyens adaptés pour actionner le poste de pose d'une languette d'ouverture lorsque les seconds moyens de détection détectent la présence d'un nouvel objet ou groupe d'objets.

The invention also relates to a machine for implementing a method according to the invention, characterized in that it comprises:

• means for driving and guiding objects or groups of objects previously wrapped in a film of synthetic film at least partially enveloping, in continuous translational movement one after the other,
• a station for cutting an incision in the form of a straight portion through the film of each object or group of objects,
• downstream of this cutting station, a station for installing an opening tab formed by a label comprising an anchoring portion and a gripping portion extending in extension of the anchoring portion, station for installing an opening tab comprising automatic means for applying a label to the film of each object or group of objects with the gripping portion which extends the anchoring portion in a direction at least substantially perpendicular to the direction of the incision as provided by the incision cutting station,
• first means of detecting the presence of an object or group of objects packed next to the incision cutting station,
• second means for detecting the presence of an object or group of objects packed next to the station for installing an opening tab,
• means adapted to operate the incision cutting station when the first detection means detect the presence of a new object or group of objects,
• means adapted to actuate the installation station of an opening tab when the second detection means detect the presence of a new object or group of objects.

A machine according to the invention is extremely compact, simple, inexpensive and can work continuously at high speed. Advantageously and according to the invention, the station for cutting an incision includes a movable knife actuated by a jack pneumatic, and the installation station of a tongue opening includes an electrical labeling device or electropneumatic.

The machine according to the invention can thus be performed in a similar way to a simple labeling machine automatic.

The invention also relates to a device easy to open, packaging, object or group of objects, a process and a machine, characterized in that that they understand in combination all or part of the features mentioned above or below.

• la figure 1 est une vue schématique en perspective d'un objet emballé avec un emballage doté d'un dispositif d'ouverture facile selon l'invention,
• la figure 2 est une vue schématique en perspective de l'objet de la figure 1 dont l'emballage est en cours d'ouverture,
• les figures 3a à 3d sont des vues schématiques en coupe verticale d'une machine selon l'invention représentant respectivement différentes étapes chronologiques d'un procédé selon l'invention,
• les figures 4a à 4d sont des vues schématiques en perspective représentant l'objet emballé respectivement au cours des étapes du procédé représentées aux figures 3a à 3d,
• les figures 5a à 5c sont des vues en élévation représentant les différentes positions du couteau rotatif du poste de découpe d'une incision d'une machine selon l'invention,
• la figure 6 est une vue schématique partielle en perspective de dessous d'une variante de réalisation d'une machine selon l'invention,
• la figure 7 est une vue de détail en coupe selon la ligne VII-VII de la figure 8, par un plan vertical perpendiculaire à l'axe de rotation d'une première variante d'un couteau de découpe d'incision d'une machine selon l'invention,
• la figure 8 est une vue en coupe selon la ligne VIII-VIII de la figure 7,
• la figure 9 est une vue similaire à la figure 7 illustrant une variante de réalisation du couteau de découpe.

Other characteristics and advantages of the invention will appear on reading the following description referring to the appended figures which illustrate a non-limiting example of embodiment of the invention, and in which:

• FIG. 1 is a schematic perspective view of an object packaged with a package provided with an easy opening device according to the invention,
• FIG. 2 is a schematic perspective view of the object of FIG. 1, the packaging of which is being opened,
• FIGS. 3a to 3d are schematic views in vertical section of a machine according to the invention respectively representing different chronological stages of a method according to the invention,
• FIGS. 4a to 4d are schematic perspective views showing the object packed respectively during the process steps shown in FIGS. 3a to 3d,
• FIGS. 5a to 5c are elevation views showing the different positions of the rotary knife of the station for cutting an incision of a machine according to the invention,
• FIG. 6 is a partial schematic perspective view from below of an alternative embodiment of a machine according to the invention,
• Figure 7 is a detail view in section along the line VII-VII of Figure 8, by a vertical plane perpendicular to the axis of rotation of a first variant of an incision cutting knife of a machine according to the invention,
• FIG. 8 is a sectional view along line VIII-VIII of FIG. 7,
• Figure 9 is a view similar to Figure 7 illustrating an alternative embodiment of the cutting knife.

In Figure 1, a article 1 (dotted), overall shape parallelepiped, wrapped in film 2 of film tearable synthetic. The invention is also applicable to pack objects or articles 1 of any other form, either individually or in groups. The film 2 can form either a primary packaging, either secondary packaging or packaging or overpack ...

Film 2 is placed and shaped entirely around article 1, and therefore presents the final shape and appearance of the packaging. In the example shown, film 2 is formed of a film heat shrunk. The invention is applicable to any film tearable synthetic. Among the synthetic films tearable, one can cite mono-oriented synthetic films, and more particularly and advantageously the foldable and / or heat shrinkable films. Such a film 2 is usually applied tightly to the touch of article 1. This article 1 can be a product generally soft food (portion of cheese, meat ...) or non-food which can be hard and rigid (cassette, book, record, pack of cigarettes, ...).

The wrapped item 1 includes a device 3.5 easy opening of the packaging formed from the film 2. This device comprises a rectilinear incision 3, that is to say in the shape of a straight portion, formed through the film 2 over at least part of its thickness, and general over its entire thickness in the case of a thin film (conventionally around 10 µm), and a tab 5. The opening tab 5 includes a anchoring portion 6 welded or glued to the outer face 7 of film 2, covering incision 3, and a gripping portion 8 allowing the user wishing open the packaging to grasp the opening tab 5. The orientation and location of incision 3 on the film 2 and relative to object 1 do not have of importance in the context of the present invention and can be any. The gripping portion 8 is a portion of the tongue 5 which is adjacent to the anchoring portion 6 and which extends free in extension of the anchoring portion 6, and the opening tab 5 is oriented and placed on the film 2 with respect to the incision 3 with its gripping portion 8 which extends the anchoring portion 6 in at least one direction substantially perpendicular to the main direction that the right 3 incision is made. So, when the user grasps the gripping portion 8 and that it exerts traction on the opening tongue 5 tending to move aside the gripping portion 8 of the film 2, it first takes off part 12 of the anchoring portion 6 which extends between the incision 3 and the common edge 9 of the anchoring portion 6 and the portion of grip 8. When this detachment leads to the incision 3, the two edges facing the incision 3 tend to deviate, which triggers the tearing of the film according to generally divergent tear lines, such as represented figure 2. The incision 3 right is thus formed a single fine straight slit made through the film which forms a primer for two tear lines 14, 15 to from respectively the two ends 16, 17 of incision 3.

The opening tab 5 is adapted and associated in such a way that the anchoring portion 6 covers incision 3 entirely. This preserves the seal between the contents of the packaging (article 1) and the outside.

As opening tab 5, you can use a label made of a synthetic film affixed covering the incision 3. This label has glue or self-adhesive 10 on at least one portion of its surface so that it can be glued to the film 2 and form said anchoring portion 6. The grip portion 8 is a portion of the label which is adjacent to the anchoring portion 6, and which is free of glue or self-adhesive, or with a coating (varnish, paper, film ...) neutralizing the glue or self-adhesive, or with type adhesive repositionable, i.e. allowing takeoff subsequent manual easy. In this way, this portion 8 of grip is not glued to film 2 so definitive and can be easily gripped by the user with a view to opening the packaging.

The anchoring portion 6 of the tongue opening 5 on the film 2 can be fixed by bonding with glue or adhesive 10 which can be all types (thermo-adhesive, contact adhesive, etc.). Also, the anchoring portion 6 can be fixed to the film 2 by heat sealing or in any other way equivalent.

Anyway, glue and / or adhesive and / or the weld used to fix the anchoring portion 6 to film 2 is adapted to allow dissociation subsequent part 12 of this anchoring portion 6 when the user pulls on the portion of gripping 8, so that the opening tab 5 is detaches from the film 2 to the incision 3, as described above. But the glue and / or the adhesive and / or the solder are strong enough to maintain a residual part 13 of the anchoring portion 6 associated with film 2, to allow subsequent tearing initiated by incision 3, by pulling the user on the tongue 5, the residual part 13 of the portion anchor 6 remaining attached to the film, as shown figure 2.

Advantageously and according to the invention, the opening tab 5 is oriented and placed in such a way so the incision 3 is closer to the common edge 9 of the anchoring portion 6 and the gripping portion 8 that from the opposite extreme edge 11 of the anchoring portion 6. If necessary, we can foresee that the glue or the adhesive covering the anchoring portion 6 on a part opposite to the gripping portion 8 -in particular on said part 13 residual - more resistant than glue or adhesive covering the rest of the anchoring portion 6 -in particular the part 12 of the anchoring portion extending between the incision 3 and the common edge 9-. For example, the portion gripping 8, and the adjacent part 12 of the portion anchor 6 to incision 3 have adhesive repositionable while the residual part 13 is provided an irreversible permanent adhesive that cannot subsequently be lifted off. In practice, this is only general not necessary because the resistance opposed by the film becomes much less important as soon as the incision 3 is discovered and that the tear lines 14, 15 are primed.

In the case of a food item, the anchoring portion 6 may have an area of its surface contact with the film 2 which is free of adhesive or self-adhesive or coated (varnish, paper, film ...) neutralizing glue or self-adhesive facing of incision 3. In this way, this zone is inert chemically and biologically so that it can be placed in hygienic contact with a food product. Alternatively or in combination, an adhesive can be used or a food grade adhesive.

Advantageously, the opening tab 5 consists of an adhesive label, the portion of which anchor 6 has an adhesive, the portion of grip 8 being formed of a portion of this label where the adhesive is removed or neutralized. Generally, labels are associated with a support 46 (figure 4d) from which they can be detached (in general, a silicone film strip). The gripping portion 8 can then also be made up of a portion opposite which the removable support 46 of the label is cut and left in place when the opening tab 5 is applied and bonded to the film 2.

Advantageously and according to the invention, the length of the anchoring portion 6 in the direction perpendicular to incision 3 and from incision 3 opposite the gripping portion 8, i.e. the length of said residual part 13 opposite the gripping portion 8, is greater than 5 mm -in particular between 10 mm and 50 mm-. In addition, the length of the incision 3 is between 2 mm and 50 mm -in particular between 5 mm and 15 min. Furthermore, the length of the incision 3 is of the order of 50% to 90% of the width of the anchoring portion 6 in the same direction. We have in effect noticed that these dimensions and proportions are particularly advantageous and effective with the majority 2 tear-off films (whatever their nature and dimensions), and with a tab opening 5 formed by an adhesive label traditional.

In the embodiment shown on the figures, advantageously and according to the invention, the width of the gripping portion 8 parallel to incision 3 is less than that of the anchoring portion 6. In this way, we save material, and we facilitates the identification of the gripping portion 8 and of the direction in which traction should be exerted by the user. So the use of the device easy to open according to the invention is particularly simple and intuitive. Also, it is advantageous to provide that the width of the gripping portion 8 parallel to incision 3 is less than the length of incision 3 in the same direction. Indeed, so, the traction exerted by the user on the portion gripping 8 has the effect of spreading more quickly the two edges opposite the incision 3 when the latter comes to be discovered. Advantageously, the portion anchor is centered axially with respect to the incision 3, and the gripping portion 8 is axially centered by relative to the anchoring portion 6 and to the incision 3.

An example is shown in the figures for carrying out the process and the machine according to the invention making it possible to provide a packaging formed with a at least 2 tear-off synthetic film partially enveloping, previously placed and fashioned around an object or group of objects (article 1) an easy opening device 3, 5 as described above. It should be noted that the method according to the invention is performed after placing and shaping said film 2 around said object or group of objects 1, until giving it its final shape and appearance for the packaging of said object or group of objects. This process can be integrated into a packaging process, in the final or intermediate phase (in the case where another packaging is then placed), or contrary is executed independently and separate from method of packaging the object itself by placing and forming the film 2 of tearable synthetic film around the object or group of objects. So the machine according to the invention is supplied with objects or groups objects previously wrapped in film 2, such as shown in Figure 4a. From these objects or groups previously packed objects, the process according to the invention consists in providing them with a device easy to open 3, 5.

The machine according to the invention shown in the figures is in the general form of a automatic labeling machine. In the example shown, the packaged item 1 is assumed to be generally in shape parallelepiped. However, this form is by no means compulsory case and the machine and the method of the invention can also be applied to all other forms of objects or groups of objects. The machine according to the invention essentially consists of a frame 20 carrying a motorized lower conveyor 21, for example by a electric motor 57, able to drive and guide the objects or groups of objects 1 previously packed in continuous displacement in translation one after the other others, at constant speed. The conveyor 21 is advantageously formed of two endless conveyor belts 21a, 21b, of the same width, parallel to each other, and distant from each other so as to allow passage between them the tools for cutting the incision 3 and for laying opening tab 5.

Under the conveyor 21 there is a station cutting 22 of the incision 3 in the form of a straight portion, and, a little further downstream depending on the direction and direction for driving objects or groups of objects 1, a post fitting 23 of the opening tab 5.

The machine further includes a first detector 24 of the presence of an object or group of objects packed 1 next to the cutting station 22, and a second detector 25 of the presence of an object or group of objects packed 1 next to the installation station 23. Preferably, the detectors 24, 25 are of the optical type (photoelectric cells).

Packaged items 1 are guided and held on the lower conveyor 21 thanks to a upper conveyor 39 with belt and rollers mounted elastically in the vertical direction which comes them apply against the lower conveyor 21. The conveyor 39 is synchronized with the lower conveyor 21. The upper conveyor 39 extends at least opposite stations 22, 23 for cutting an incision 3 and placing an opening tab 5. In addition, this conveyor upper 39 is advantageously fixed relative to the frame by means of an adjustment console 40 allowing, thanks to a crank 41 associated with a worm and vertical slides, adjust the vertical position relative to the lower conveyor 21, depending on the thickness of articles 1 to be treated. Also, lateral guides 42 are provided on each side of the conveyor 21, to guide laterally the articles 1 on the move. These guides side are formed by ramps mounted relative to the frame 20 by adjustable fixing means 58 making it possible to vary their relative spacing.

In addition, the machine is equipped with means automatic (electronic and / or computer) adapted to operate the cutting station 22 when the first detector detects the presence of a new object or group objects 1, and automatic means (electronic and / or adapted to operate the installation station 23 when the second detector detects the presence of a new object or group of objects 1. A control console 26 allows you to make settings and order in general the machine.

Figures 5a to 5c further illustrate details, the incision 22 cutting station. includes a movable knife 27 rotatable about an axis horizontal 28. This axis 28 is fixed relative to the frame 20 and extends parallel to the direction of training in translation of articles 1 by the conveyor 21. From the so, the deflection plane of the knife 27 is a plane vertical perpendicular to the direction of movement of the conveyor 21, that is to say a vertical transverse plane. This knife 27 is controlled in its rotational movements around the axis 28 thanks to a pneumatic cylinder whose body 29 is fixed to the frame 20 and whose rod 30 actuator is connected to a connecting rod 31, itself connected to a crank 32 secured to the knife 27. The mechanism connecting rod / crank thus formed allows to drive the knife in rotation during reciprocating movements of translation of the jack. The axis 28 of the knife 27 is placed by compared to conveyor 21, and the whole mechanism is adjusted so that when the cylinder rod 30 deploys (from Figure 5a to Figure 5c), the knife 27 describes an arc passing through a slot 33 formed through a median plate 34 of the conveyor 21 fixed rise relative to the frame 20 and extending longitudinally between the two upper strands of the carpets 21a, 21b. In doing so, the knife 27 has its end sharp protruding above the upper side of the plate 34, so as to come into contact with the face bottom of item 1 packed opposite to protect through film 2 of this article 1, an incision straight line 3 in the transverse direction, that is to say perpendicular to the conveyor direction of travel 21. The length of the incision 3 thus formed depends on the length of the knife 27 relative to its axis of rotation 28 and the depth of penetration of the knife into item 1 packed.

The knife 27 is advantageously made up a blade 35 mounted on a support 36 movable in rotation around the axis 28. The crank 32 is integral with the support 36. For example, it consists of a extension of the support 36. The support 36 is itself rotatably mounted around the axis 28 and defines a range 37 protection able to come into contact with the film 2 to limit the penetration of the blade 35 through the film 2. In the case of a rotary knife, as shown, protection range 37 is a portion of surface of revolution around axis 28, in particular a portion of cylinder of revolution.

The blade 35 is advantageously mounted by relative to the support 36 in an adjustable manner so that the height of this blade 35 projecting from the span 37, and therefore the depth of penetration of the knife 27 into item 1 packed, can be paid. In addition, the blade 35 is mounted so that it can be changed and replaced. The axis 28 is carried by a support piece 38 itself fixed to the frame 20 by means of height adjustment of its position (for example two vertical oblong lights crossed by bolts tightening, as shown in Figures 5a to 5c).

By adjusting the height of the blade 35 in projection from its support 36 and the position of the support 38 relative to the frame 20, it is thus possible to adjust the length of the incision made through the film 2.

Note that incision 3 is performed through film 2 while article 1 packed is driven continuously without interruption in translation by the conveyor 21 perpendicular to the main direction of the incision 3 thus produced (the operating speed of the jack 29 being very much higher than the forward speed articles 1 on the conveyor 21).

An example of how the height adjustment of the protruding part of the blade 35 outside the support 36, appears in Figures 7 to 9. The blade 35 is generally in the form of a plate having a straight lower edge. The cutting part of the blade 35 has an acute angle 52 projecting from outside the support 36 for cutting the incision 3. Support 36 has a central groove 49 for receiving the blade 35 between two sides 59 of the support 36 which is therefore shaped general screed. The groove 49 has a flat bottom 50 receiving the lower edge of the blade 35. This bottom 50 is inclined so that by sliding the blade 35 on this bottom 50, the acute angle 52 cutting the blade 35 protrudes more or less outside the support 36 by relative to the bearing surface 37. A clamping screw 48 is screwed in a thread through one of the flanks 59 of the support 36, so that the end of this screw 48 comes resting against the blade 35 to tighten it in position against the other flank 59. In the alternative embodiment of Figure 9, you can adjust the blade 35 in any position relative to the bottom 50. In the alternative embodiment shown in Figures 7 and 8, there is also provided a drilling through the two sides 59, and a pin 51 wedging allowing, with each blade change 35, to replace a new blade 35 without requiring a new one setting. So, once a first position adjustment blade 35 determined from the knife shown Figure 9, drilling is carried out and a pin 51 is placed to obtain the variant of FIGS. 7 and 8 making it possible to easily keep this setting when changing later of blade 35 by an identical new blade. The pin 51 also serves as a stop for the rear edge 53 of the blade 35 perpendicular to the bottom 50, so that the blade 35 is better locked in position, without rotation possible, in the support 36.

The slot 33 made through the plate 34 of the conveyor 21 is of a width such that it leaves pass the blade 35, and the scope 37 of protection. Of the so, during the rotation of the knife 27, the range of protection 37 comes into contact with film 2.

The operation of the cutting station 22 and of the jack is triggered by the first detector 24 as soon as this detects the presence of an article 1 next to it transversely of this first detector 24. The detector 24 is placed in a longitudinal position with respect to the slot 33 of the plate 34, and therefore relative to the knife 27, appropriately to allow the realization of incision 3 at the desired location on film 2 of item 1 packed.

As soon as the first detector 24 detects plus the presence of section 1 on which incision 3 has just been made (Figures 3c and 4c), the knife 27 is returned to the initial position to perform a new incision 3 on a subsequent new article 1, thanks appropriate programming of said automatic means adapted to operate the cutting station 22. As a variant, the knife 27 can be of the bidirectional type, so that ability to make an incision 3 alternately in two directions of rotation around the axis 28.

The installation station 23 with a tongue opening 5 includes automatic laying means labels on film 2 of each object or group of objects 1, and therefore consists of a device labeling whose general constitution and operation are known in themselves. This installation station 23 is, like the cutting station 22, arranged under the lower conveyor 21, and has a plate of presentation and distribution 43 of labels arranged under a rectangular light 44 of dimensions corresponding, formed through the plate 34 of the conveyor 21. In a variant not shown, a device pneumatic or electropneumatic can also be provided to recover each label from the support strip 46 and apply it on the film 2. The installation station 23 of labels forming the opening tabs 5 is powered by an electric motor.

The opening tabs 5 are formed adhesive labels which are in the form of a roll of labels placed one after the other on a support strip 46 wound on itself in spiral, in a traditional way. Band 46 is guided by a series of rollers or rollers to the extreme edge of the plate 43 for presentation and distribution of labels through the light 44. The support strip 46 is folded around this edge, then guided by rollers or rollers up to a motorized receiving drum 47. When the drum 47 is wound up, the band 46 moves along the edge of the plate 43, which has the effect of release a new label, i.e. a new one opening tab 5 which is applied and adhered against the film 2 of an article 1 passing next to light 44 (Figure 4d).

The opening tabs 5 are placed on their detachable support strip 46 so that the gripping portion 8 extends the anchoring portion 6 adhesive in a direction perpendicular to the direction incision 3 as previously prepared by the cutting station 22. Similarly, the edge of the plate 43 presentation and distribution of the tabs opening 5 is perpendicular to the direction of advance of the conveyor 1 and to the axis 28 of rotation of the knife 27. When the second detector 25 detects the presence of a article 1 packed, said automatic means adapted for operate the installation station 23 operate the engine electric drive in rotation of the drum 47, so that an opening tab 5 is applied to the film 2 of article 1 opposite. Again, the detector 25 is placed in the longitudinal direction drive of the conveyor 21 relative to the plate 43 presentation and distribution of tabs 5, appropriately to affix the opening tab 5 suitably as described above, relative to the incision 3.

In the variant shown Figure 6, we place the cutting station 22 as close as possible, in the longitudinal direction, from the installation station 23. To do this, the plate 43 for presentation and label distribution which is mounted in solidarity with the housing 55 of the labeling device, has a part vertical 54 of height at least equal to that of the cutout 22 (cylinder 29, 30 and knife 27) so as to adjoin, and an extreme portion 56 inclined downstream by relative to the plane of the plate 34 of the conveyor 21 for applying the opening tabs 5. The rollers or guide rollers for the label strip 46 are worn by the plate 43 and / or by the casing 55. The detectors 24, 25 are also closely matched. Of the so, the installation of the opening tab 5 occurs immediately after cutting incision 3, which improves the precision of the installation of the tongue 5 compared to the incision 3. With this mode of realization, if a return of the knife 27 in position initial step is planned (step of Figures 3c and 4c), this is only carried out after installing the opening tab 5 (step of Figures 3d and 4d).

The entire labeling system is mounted relative to the frame 20 on a common support whose vertical position relative to the conveyor plate 34 21 is adjustable, for example using a console crank, worm and slide, similar to that allowing the adjustment of the upper conveyor 39. From the so we can adjust the position of the plate 43, in particular of its extreme portion 56 with respect to the light 44 and articles 1 packed.

The different items 1 packed are succeed one after the other, with spacing between them sufficient to allow the functioning of detectors 24, 25 and stations 22, 23 for cutting and pose.

In the process according to the invention, cleaning therefore through film 2, a single incision 3 giving it the shape of a straight portion and we pose and we orient the opening tab 5 on the film 2 with its gripping portion 8 which extends the portion anchor 6 in at least one direction perpendicular to the main direction of the incision 3. The steps of cutting the incision 3 and performing fitting the opening tab 5 successively on 1 packaged objects or groups of objects that are trained in continuous movement without interruption, in translation according to a direction at least substantially perpendicular to the main direction of the incision 3.

Claims (10)

1. Method for providing a package made of a tearable at least partially enveloping synthetic film, previously disposed and shaped around an item or a group of items, with an easy opening device comprising an incision (3) provided through the film (2) and an opening tab (5) comprising an anchoring portion (6) welded or stuck on the outer face (7) of the film (2) by covering the incision (3), and a handle portion (8) in free extension with the anchoring portion (6), wherein :

   the incision (3) is provided through the film (2) as a straight line portion,

   the opening tab (5) is laid and oriented on the film (2) with its handle portion being in extension with the anchoring portion (6) in a direction at least substantially perpendicular to the main direction of the incision (3),

      characterised by the carrying-out of the steps of cutting the incision (3) and laying the opening tab (5) successively onto packaged items or groups of items (1) which are driven in a continuous movement without any translation interruption.
2. Method according to claim 1, characterised in that the packaged items or groups of items are driven in a translational movement in a direction least substantially perpendicular to the main direction of the incision (3) to be provided.
3. Method according to one of the claims 1 or 2, characterised in that the opening tab is laid and oriented so that the incision (3) is closer to the common edge (9) of the anchoring portion (6) and the handle portion (8) than to the extreme opposing edge (11) of the anchoring portion (6).
4. Method according to one the claims 1 to 3, characterised by the use of a knife (27) rotatable around an axle (28) parallel to the movement direction of the packaged items or groups of items in order to provide the incision.
5. Method according to one of the claims 1 to 4, characterised by the use of a knife (27) comprising a blade (35) fitted on a movable support (36) defining a protective bearing portion (37) able to contact the film (2) for limiting the penetration depth of the blade (35) through the film (2) in order to provide the incision (3).
6. Machine for implementing a method according to one of the claims 1 to 5, characterised in that it comprises :

   driving and guiding means (21, 39, 42) for driving and guiding items or groups of items (1), previously packaged with an at least partially enveloping synthetic film (2), successively moving in a continuous translational movement,

   a cutting station (22) for cutting an incision (3) as a straight line portion through the film (2) of each item or group of items,

   a laying station (23), provided downward this cutting station (22), for laying an opening tab (5) formed by a label comprising an anchoring portion (6) and a handle portion (8) in extension with the anchoring portion (6), this laying station (23) for laying an opening tab (5) comprising automatic means for laying a label onto the film (2) of each item or group of items with the handle portion (8) in extension with the anchoring portion (6) in a direction at least substantially perpendicular to the direction of the incision (3) such as provided by the cutting station (21) for cutting an incision,

   first detection means (24) for detecting the presence of a packaged item or group of items opposite to the cutting station (22) for cutting an incision,

   second detection means (25) for detecting the presence of a packaged item or group of items opposite to the laying station (23) for laying an opening tab (5),

   means adapted for actuating the cutting station (22) for cutting an incision when the first detection means (24) detect the presence of a new item or group of items,

   means adapted for actuating the laying station (23) for laying an opening tab when the second detection means (25) detect the presence of a new item or group of items,
7. Machine according to claim 6, characterised in that the cutting station (22) for cutting an incision comprises a knife (27) rotatable around an axle (28) at least substantially parallel to the movement direction of the packaged items or groups of items.
8. Machine according to one of the claims 6 and 7, characterised in that it comprises means adapted for positioning again the cutting station (22) for cutting a new incision (3) after providing the incision (3), when the first detection means (24) do not detect anymore the presence of the item or group of items.
9. Machine according one of the claims 6 to 8, characterised in that the driving and guiding means (21, 39, 42) comprise an lower conveyor (21), that the stations (22, 23) for cutting an incision and laying an opening tab are disposed under the lower conveyor (21) provided with ports (33, 34) opposite to theses stations (22, 23), and that the driving and guiding means comprise, at least opposite to the stations (22, 23) for cutting an incision and laying an opening tab, an upper conveyor (39).
10. Machine according to one of the claims 6 to 9, characterised in that the cutting station (22) for cutting an incision comprises a movable knife (27) actuated by a pneumatic jack (29, 30), and that the laying station (23) for laying an opening tab comprises an electric and/or electropneumatic labelling device.

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