Description Field of the art

The present invention refers to the field of packaging, and in particular to a new system for the obtainment of containers used for containing food products, and preferably used for containing liquids. More in detail, the present invention refers to a new packaging machine capable of optimizing the production yield of already-known methods for producing said containers. The present invention also refers to the relative process for obtaining the containers.

State of the art

Many different production techniques and methods are known for obtaining packaging products, used for containing goods, with characteristics such to allow the handling of said goods. Packaging containers, commonly known as packaging products, must comply with various requirements aimed to accomplish the functions of: protecting the goods, preventing theft, and they must be substantially inexpensive, given their by now extremely widespread use. Said containers, for such purpose, must be obtainable with production methods that provide for the processing of specific materials in relatively brief time periods and with low costs.

Among the most diffused packaging containers in the alimentary field, those of parallelepiped form used for containing liquids such as milk or fruit juices are certainly to be considered.

Currently, two methods are the most widely used industrially for obtaining said box containers. The first uses packaging machines in which the container with parallelepiped form is obtained by welding, longitudinally together, the external side and the internal side of a strip of polylaminate material having a cardboard layer, where by external side and internal side it is respectively intended the side of material that will come to constitute the outside and the inside of the container. The welding in question allows obtaining a tube, which is then further transversely welded in a manner so as to form bags containing, by way of a non-limiting example, the liquid. Said bags are subsequently given parallelepiped shape. The limit of this technology, even if widely used, lies in the drawback of encountering one of the edges of the sides, of polylaminate material, inside the container, following the first longitudinal welding. In order to prevent said longitudinal edge, inside the tube thus formed, from subsequently coming into contact with the liquid, the technology in question provides for the use of a protective strip, made of plastic and impermeable material, to be superimposed, inside the tube, on the border of the polylaminate material.

The second method, less diffused than the first, instead uses packaging machines which allow obtaining the container with parallelepiped form starting from a welding executed, always longitudinally, between the internal sides of the strip of polylaminate material, hence without involving its external surface. Said welding allows obtaining a tube in which the use of a protective strip is not required, since both lateral end edges of the polylaminate material, having the cardboard exposed, are situated outside the package and therefore not in direct contact with the food.

The packaging machines employ a system of sterilization of the strip that consists of making said strip pass inside a bath containing a mixture of hydrogen peroxide and water at a temperature of approximately 75 °C - 90 °C. There are in any case other sterilization systems that can be employed, including that consisting of applying a film, composed of a mixture of hydrogen peroxide and water, by means of a roller or by making said mixture condense on the surface of the strip to be sterilized.

The packaging machines used in the first described method, i.e. those which form a circular tube by welding together the edges of the internal and external side of the strip of polylaminate material, have currently reached a fairly good production speed, obtained by multiplying in longitudinal sense the welding groups that progressively interact with the strip. Said increase was initially obtained by means of two welding heads that are spaced with an alternating motion, and subsequently, by means of rotary welding chains. At any rate, both of these solutions prevent the strip from having to stop, rather they allow the same to be longitudinally moved in continuous motion.

The packaging machines of the second type, i.e. those which form the tube by welding the edges of the internal sides of the strip of polylaminate material, are instead still today characterized by low production speed, since the packaging machines employed move the strip in an intermittent manner, in order to be able to weld the containers with a single stationary welding station. In any case, the merit of this system is represented by the low cost associated with this technology, and by its relative simplicity, since there is only one welding group. Its limit is instead substantially due to the low production capacity due to the absence of a continuous motion of the strip. A possible solution, employable for increasing the productivity of these packaging machines, could consist of increasing the flows of material that are inserted in the machine, for example by coupling multiple machines in series; however, this solution would not represent a technological innovation, but rather an engineering adapted to increase the quantity of exiting product, by simply increasing the production lines of the packaging machine.

The present invention, described in detail hereinbelow, instead allows attaining a substantial doubling of the production capacity of these packaging machines, i.e. including the welding only of the internal sides of the strip. This is obtained not by multiplying the number of strips of material to be used and the number of lines conveying said strips, but rather by employing a procedure and components integratable in the machinery which, suitably configured in space, allow doubling the productivity of said packaging machines - known but fallen out of use - without considerably increasing the complexity and cost of the machinery itself.

Description of the invention

The present invention describes a new type of packaging machines, adapted to produce, on an industrial scale, packaging, and in particular adapted to produce box containers used for containing liquids such as, by way of a non-limiting example, milk and fruit juices. More in detail the present industrial invention patent application describes a packaging machine for producing box containers in polylaminate material, and the relative process for obtaining said food containers. Still more in detail, the present invention refers to a packaging machine which executes a procedure of processing of the strip, which is already known but made decidedly more productive. This important result, also associated with a relatively low cost of the machinery, is obtained due to the employing of expedients and the use of components, and especially due to a particular arrangement of said components of the machinery, which allow doubling the production yield by starting from a single reel of strip material made of polylaminate. Said strip is processed according to known methodology which includes, in the steps thereof, the execution of a welding of the strip involving only the edges of the internal sides of said strip, i.e. of the sides which will come to constitute the interior of the container. All of this with a doubled yield of the containers produced, with respect to conventional methodology, and with a relatively low cost.

The packaging machine, object of the invention, and the relative method of preparation of the containers produced thereby, use, as starting material, a reel of single strip with double- band, with two graphical strips printed, and possibly having two rows of perforations for the opening devices such as hole/straw or hole for the metering cap. The strip is directed upward, analogous to that provided by conventional methodology, passing through a creasing group, where the fold lines are imparted on the strip which then passes through a compensator group, adapted to compensate for the jerk/pull-movements of the intermittent motion deriving from the movement of the filling zone. The strip is then longitudinally cut at the center, in a manner so as to form two strips that are independent from each other. Subsequently, the two strips thus obtained are deflected, one to -90°, the other to +90° with respect to the advancing direction of the entering strip, passing over two bars preferably placed with one at -45°, the other at +45° with respect to said advancing direction. The two independent strips are subsequently sterilized in two separated sterilization baths before passing over a series of rollers which carry the same strips towards the center of the machine with the side that will come to constitute the interior of the container directed upward, and the side having the graphics, i.e. the side which will come to constitute the exterior of the container, directed downward. Subsequently, the two sterilized strips, passing over rollers, vertically proceed, as occurs in conventional machinery, towards the tube formation and welding zone. In this step, the two strips, precursors of the tubes, are situated with their internal sides, i.e. with their sides that will come to constitute the interior of the containers, opposite each other. Therefore, the entire sterile air group that ensures the presence of said air inside the product being processed, as well as the formation group of the two tubes of polylaminate material, in the present invention result the only groups for the two joining flows of material. The same holds true for the longitudinal and transverse welding mechanisms for the strips. These characteristics allow, with a single movement mechanism, to simultaneously weld two flows of strip material. All of this occurs by intuitively optimizing the production yield. The cut containers that then exit from the filling zone, after having been cut, are also situated in a manner so as to be parallelepiped shaped over a single double-row formation group. In addition to the clear increase of production yield, the procedure executed by the present packaging machines, as well as said packaging machines, occupy a substantially smaller volume of space due to the particular arrangement of the integrated components, and they do not oblige the doubling of the production costs, even if the doubling of the yield is attained.

Brief description of the drawings

FIGURE 1 shows a perspective view of the packaging machine 1 of the packaging system, object of the present industrial invention patent application. More in detail the figure shows how said packaging machine 1 transforms, starting from a reel 2 of strip material 3, said strip 3 into box containers. Observing the figure, it is noted that the strip 3, unrolling upward, proceeds through the creasing group 4 adapted to impart the fold lines on the strip, in order to then be cut into two portions of equivalent extension, i.e. into the strip 3 ' and strip 3", by means of the cutting device 6. The two strips 3' and 3" are then orthogonally deflected with respect to the initial direction of the strip 3, due to two bars 7 which, in the figure in question, are arranged at +45° and at -45° with respect to said direction of the main strip 3. The strips 3' and 3" thus deflected, one to +90°, the other to -90° with respect to the strip 3, are sterilized in the suitable sterilization tanks 8' and 8" containing hydrogen peroxide. By means of the passage above a plurality of rollers 9, said strips 3' and 3 " are led towards the center of the packaging machine 1, in a manner so as to be vertically arranged opposite each other. Subsequently, the strips 3 ' and 3 " are longitudinally welded, by means of at least one suitable welding group 10, and cut by means of at least one transverse welding group 10', in order to then be transformed, with mechanisms of known type, into box containers due to a suitable double-row device 11.

FIGURE 2 shows a side view of the present packaging machine 1. The figure in question shows, more in detail, the presence of the creasing group 4; of the cutting device 6; of the compensator group 5 adapted to compensate for the possible jerk/pull-movements due to the intermittent motion; of one of the sterilization tanks, i.e. tank 8'; of the welding group 10; and of the device 11 for transforming the strips 3' and 3", previously welded longitudinally and transversely, into box containers.

FIGURE 3 shows a plan view of the packaging machine 1, in which the path of the strips 3 ' and 3" is shown, once the cutting of the main strip 3 has occurred. More in detail, the figure emphasizes how said strips 3 ' and 3 " are directed orthogonally with respect to said main strip 3, due to the bars 7 arranged at +45° and at -45° with respect to the direction of the strip 3. Also represented are the compensator group 5, the sterilization tanks 8' and 8", and the double-row device 11.

Description of the preferred embodiments

In its preferred embodiment, the packaging machine 1 adapted for producing containers for foods, starting from a reel 2 of strip material 3 of polylaminate material, and object of the present industrial invention patent application, comprises, proceeding from upstream to downstream of the processing of said strip 3 : at least one creasing group 4, adapted to impart the fold lines on the strip 3; at least one compensator group 5 adapted to compensate for the possible jerk/pull-movements of the intermittent motion; at least one cutting device 6 placed before said group 5 and adapted to divide the main strip 3 in at least two independent strips 3' and 3 "; at least two bars 7, arranged preferably with one at -45°, the other at +45° with respect to the direction of the main strip 3, adapted to deflect said strips 3' and 3" orthogonally with respect to the direction of said main strip 3; at least two sterilization tanks 8' and 8", one adapted to sterilize the strip 3 ', the other the strip 3"; a plurality of rollers 9 adapted to lead said independent strips 3' and 3" towards the center of the packaging machine 1, in a manner such that the same strips 3' and 3" have their internal side, i.e. that which comes to constitute the internal wall of the container/containers, directed upward, and their external side, having the graphics, directed downward, in order to then proceed vertically towards at least one welding zone 10 adapted to weld said strips 3' and 3" in a manner such that each of these forms a tube. Said tubes are subsequently transversely welded, by means of at least one suitable transverse welding group 10', so as to then be intended to be developed into food containers with devices and mechanisms of known type. Said packaging machine 1 for such purpose comprises, downstream, a common double-row device 11, adapted to transform the tubes, obtained following the welding of the tubes 3' and 3", into box containers with preferably parallelepiped form. As mentioned above, the present industrial invention patent application also refers to the process, using the abovementioned packaging machine 1 for producing said containers for foods.

The process in question allows doubling productivity, by employing the same principles of the mechanics of conventional technology. It is indeed possible to produce two containers at a time, since, due to the particular arrangement of the components of the packaging machine, the longitudinal and transverse welding, as well as the step of filling the containers thus produced, take place simultaneously.

Said process comprises the following steps in sequence: a) upward unrolling of a reel 2 of strip material 3 made of polylaminate material;

b) passage of said strip 3 through at least one creasing group 4;

c) cutting of said strip 3, into at least two strips 3' and 3", independent of each other, due to a cutting device 6 such as a common blade;

d) directing said strips 3 ' and 3" orthogonally with respect to the direction of the main strip 3, due to at least two bars 7 preferably arranged with one at -45°, the other at +45° with respect to said direction of the main strip 3.

e) sterilization of said strips 3' and 3", orthogonally deflected with respect to the direction of the main strip 3, respectively inside the sterilization tanks 8' and 8" containing H ₂ 0 ₂ ;

f) automated exit of each strip 3 ' and 3 " from the respective sterilization tank 8' and 8", and passage of said strips 3' and 3 " through a plurality of rollers 9 which lead each strip towards the center of the packaging machine 1, and direct them vertically, arranging them opposite each other, in a manner such that each strip turns its internal side towards the internal side of the other strip;

g) simultaneous longitudinal welding of each strip 3 ' and 3 " by means of at least one welding group 10, and subsequent transverse welding of the tubes, by means of at least one transverse welding group 10', in order to obtain the cut containers;

h) filling of said cut containers with the liquid;

i) transfer of said containers to a common device 1 1 which transforms said containers into box shape.