EP0951423A1

EP0951423A1 - Package for solid or pasty products and method and apparatus for its manufacture

Info

Publication number: EP0951423A1
Application number: EP98950251A
Authority: EP
Inventors: Ivo Longhi; Angelo Deserti
Original assignee: OFFICINE MECCANICHE NATALINO CORAZZA SpA
Current assignee: OFFICINE MECCANICHE NATALINO CORAZZA SpA
Priority date: 1997-11-07
Filing date: 1998-11-06
Publication date: 1999-10-27
Also published as: ITBO970663A1; ITBO970663A0; AU9640298A; IT1296544B1; WO1999024321A1

Abstract

The package is realised using a section of film of non paper and non metallic, heat-weldable material; the subject method entails forming said section (2) into a bag within a pit-shaped forming hopper, by means of a piston (5) able to shape said container (4) in concurrence with the walls of the forming hopper (3), and it provides for the use of pressing means, (8, 9) associated to said hopper, to fix, in a permanent manner, and in concurrence with said piston, one or more folding lines of the bottom and of the sides of the container obtained in said hopper, in the phase wherein, by means of said piston, the container is made to pass through the outlet of said forming hopper; for the completion of the container the method entails the use of a succession of folding means (10-12) positioned along a line of closure of the container, whereof those that effect the final and closure folds of the container also act as pressing and welding devices to seal the closed package.

Description

PACKAGE FOR SOLID OR PASTY PRODUCTS AND METHOD AND APPARATUS FOR ITS MANUFACTURE

Technical Field

The present invention relates to the package of dosed products, derived from milk, and of pats or small cubes of edible mixtures, of solid or pasty consistency.

The present invention further relates to the method for obtaining and sealing said package in automatic machines for dosing, dispensing and packaging said products, as well as the related realisation devices which can be installed on such machines or which may be comprised by said machines.

Background Art For the packaging of products of the kind indicated, universally known is the employment of sections of paper material, or of sections of material obtained from metal foils (for instance, aluminium).

Such sections of material are shaped into a bag (or folded) to form a container open at the top, within which is inserted the dosed quantity of product to be packaged. The containers are formed using automatic machines that provide for feeding individual sections of material to a hopper for forming to open container, subsequently moving such open container within a pocket presented by a conveyor which transfers it to a filling station, where a device for dispensing the dosed product is located, and subsequently along a closure line, wherefrom the package is then extracted. On such closure line operate folding devices whereby the container is closed by folding one over the other, to cover the product, portions of the upper part of the container itself. Such portions remain in the folded position thanks to the physical and mechanical characteristics of the material whereof the container is made, and, obviously, also according to the degree of definition of the folding lines effected by the folding devices that operate along said closure line.

The characteristics of the materials used for the realisation of the sections destined to form the container allow to maintain a good memory of the fold whereto the section has been subjected; on the other hand said characteristics do not allow the possibility of sealing the package by mutually attaching the parts of the container folded back to cover the product, with the consequence that the package thereby obtained can be opened and closed again accidentally or maliciously.

Disclosure of the Invention

The Applicant, with the aim and the goal of providing a sealed package of the products in question, where the term sealed package means a package whose accidental

(or malicious) opening is immediately detectable by those who were to handle it, for instance the purchaser, has intuited that in order to reach said aim and goal to realise the package it was necessary to concentrate on materials with heat-weldable characteristics, thus not paper-based or metallic materials.

In experimenting with new materials the Applicant had to solve the problems stemming from the use of plastic and heat-weldable materials with a poor aptitude for "memorising" the fold whereto the sections used in the attempt to obtain a sealed package were subjected, as indicated above.

Sections obtained from films of plastic material, such as polypropylene, precisely because they revealed a poor aptitude for maintaining the fold of their portions (or edges) were ill suited for use in packaging the products described herein, according to the known techniques for forming the container in prior art automatic machines.

In the course of the experiments conducted, the Applicant intuited that in order to stabilise the fold of a section of heat-weldable material, in particular (but not exclusively) of a section of polypropylene film, during the phase wherein the container is formed, it was necessary to act on the section with pressing devices able to fix, in contrast with abutting devices, the folding lines of the container thereby rendering them highly marked.

The Applicant intuited that using said pressing means during the initial phase wherein the open container is formed, to fix folding lines effected in correspondence with the perimeter that defines the bottom of the open container, as well as folding lines of sides of the container, obtained as an effect of the forming of the section into a bag in a pit-shaped forming hopper, according to techniques already used for paper or metal sections in traditional automatic machines, it was possible to obtain an open container with substantially stable conformation even after its extraction from said hopper and its partial insertion in one of the pockets of a conveyor for its move to the filling station and to the closure line of the package.

The Applicant has further intuited that by providing for an appropriate combination of folding devices destined to fold the container after its filling it was possible to maintain stably folded and mutually overlapping, even if only partially, the portions of the container folded in succession by the folding devices themselves; and that by providing the final folding devices in the form of heated and heating folding- pressing elements it was possible to obtain the mutual welding at least of the last folded portions.

Thus the present invention relates both to the package, and to the method for its realisation together with the devices for carrying out said method in automatic machines, as they are defined in the claims that follow.

The essential characteristics of the present invention shall now be better described with reference to some possible embodiments of the devices which allow its realisation and with reference to the accompanying drawings, purely indicative and non limiting, wherein:

- Figure 1 shows the subject package, in an axonometric view;

- Figure 2 schematically shows the phases A-B-C-D-E related to the formation of the package as per Figure 1 starting from a section of material obtained from a film of heat-weldable material, in accordance with the present invention;

- Figure 3 shows, schematically and in an axonometric view, some parts of the pit shaped forming hopper, according to the present invention, with the container that forms the package being realised, according to phase B as per Figure 2, and seen prior to its insertion in the pocket of the conveyor that transfers the container to the filling station and, subsequently, to the closure line;

- Figure 4 shows a first diagram of the disposition and succession of the interventions by the folding devices and by the folding welding devices that effect the closure of the package starting from phase B as per Figure 2; - Figure 5 shows a second diagram of the disposition and succession of the interventions by the folding devices and by the folding welding devices that effect the closure of the package starting from phase B as per Figure 2. The subject package may be realised in automatic machines of any type suitable for dosing and dispensing the products whereto the invention refers according to commonly known techniques, with the use of the devices, constituting the subject of the present invention, that allow to carry out the method which also constitutes the subject of the present invention.

For example the machines may be of the turntable type, where the forming hopper, the device for dosing and dispensing the product and the folding devices, the heated folding-pressing devices and the devices that extract the package from the closure line, are distributed at the periphery of said turntable in correspondence with stopping stations of the containment pockets of the formed and open container.

In this case, the filling hopper may be of the type with single pit or with dual pit in order to be able simultaneously to form two containers, and hence two packages, for each complete cycle of rotation of the turntable for the execution of the phases A-B-C- D-E as per Figure 2. In this case in correspondence with each operative station wherein the pockets that are to house the two containers, and hence the two packages being formed, will come to stop, shall be provided corresponding pairs of folding devices and heated folding-pressing devices for the simultaneous execution of the phases C-D-E as per Figure 2.

Said machines may also be of the type with continuous linear conveyor and of the type with multiple forming hoppers aligned transversely above each conveyor, ordered according to one or more rows.

In this case, the folding devices and the heated folding-pressing devices shall be provided downstre.am of each of said forming hoppers and positioned in correspondence with multiple stations wherein the pockets housing the formed and open containers will come to stop in succession.

With reference to Figures 1 and 2 an embodiment of the subject package is indicated with the number 1 and it is obtainable from a section 2 of plastic material, heat-weldable, obtainable - for instance - from a roll of film supported by means (not shown) that may be part of a feeding line of an automatic machine of the type indicated above, and whence the section 1 is unwound and cut to be carried to a station of the machine where phase A shown in Figure 2 is executed; that is to say, the positioning of the section 1 above a pit-shaped forming hopper 3, outlined schematically and with dashed line in Figure 3.

By means of the hopper 3, as shall be described better hereafter, Phase B as per Figure 2 is obtained, wherein the section 1 is shaped into a bag to form an open container 4, whereof the bottom is defined as well as the sides 4a and 4b. By transferring the container 4 along the line of closure of the package, as described hereafter with reference to Figures 4 and 5, one obtains the subsequent execution of the folds shown in phases C-D-E of Figure 2, where: during phase C the sides 4b of the container 4 are partially folded to cover the product placed inside the container itself, and partially superimposed one over the other; during phase D a first side 4a is partially folded and superimposed to the sides 4b previously folded; during phase E the second side 4a is partially folded and superimposed on the first, defining the closure of the package 1.

According to the present invention, phase B is obtained using the hopper 3. The main structure of said hopper 3 is known in the art and it is normally used in machines for realising packages, also known in the art, of the subject products. The hopper 3 presents along the walls that define the sides 4b of the container 4 helicoidal folding devices (not shown in the drawings) whereby a part of the section 1 is formed into a bag or folded back thereby allowing the formation of the container 4.

The section 1 is inserted into the hopper 3 by a piston 5 axially movable, in the two directions, inside the hopper 3. The piston 5 presents a shape and a section to copy those of the hopper 3 and also to copy the shape of the container 4. Said piston 5 is movable from a first position wherein it is outside and raised with respect to the inlet 3a of the hopper 3, to a second position wherein, with its lower part, it projects outside the outlet 3b of the hopper 3, subsequently to return to the starting position. The piston 5, in its second position, penetrates inside one of the pockets 6 presented by a conveyor 7 which is positioned below the hopper 3 and which in its stopped position carries a pocket 6 aligned axially with the hopper 3 and hence with the piston 5.

The pocket 6, according to the prior art in the machines indicated above, is so shaped as to house the lower part of the container 4 for a height substantially corresponding to the level to be reached by the product to be dispensed within the container itself. The aforesaid conveyor 7 may assume, in practice, the structure and the shape of a turntable, on the periphery whereof the pockets 6 are uniformly distributed; or, said conveyor 7 may be constituted by a continuous linear conveyor, on the conveying surface whereof the pockets 6 are uniformly distributed. According to the present invention the hopper 3 is equipped, in correspondence with the outlet 3b and in correspondence with the helicoidal folding devices that define the sides 4b of the container 4, with a pair of pressing devices 8.

The pressing devices 8 are constituted by a pair of rollers supported by the structure of the hopper 3 in such a way as to be in mutual diametrical opposition, with respect to said outlet 3b of the hopper 3, and mutually separated, in correspondence with the facing surfaces, by a distance that is smaller, albeit slightly, than the dimension of the piston 5 that defines the sides 4a of the container 4. The rollers 8 are supported in such a way as to be able to move away from one another and are kept in their normal close position by means of springs 9 fastened at their ends to the supporting pins of the rollers 7 themselves.

With this solution, when with the descent of the piston 5 a section 1 is inserted into the hopper 3, and the container 4 progressively traverses the outlet 3b of the hopper 3 to be inserted in the pocket 6 of the conveyor 7, the rollers 8, in concurrence with the outer surface of the piston 5, fix, with force, the folds of the sides 4b of the container 4 assuring the stable definition of said folds and hence of the container 3 in its condition as per Phase B of Figure 2.

With the insertion of the container 4 in the pocket 6 of the conveyor 7 and with the return of the piston 5 in the starting position, the transfer begins of the container 4 to a filling station, where a dosing-dispensing device places a wanted and proportional dose of product inside it, and subsequently to a line of closure of the package 1 which shall now be described according to the embodiments shown in Figures 4 and 5 of the accompanying drawings.

With reference to Figure 4, the aforesaid line of closure of the package 1, especially in the case wherein the conveyor 7 is constituted by a turntable, comprises, downstream of the filling station of the container 4, a station S wherein phases C-D as per Figure 2 can be executed, whereas phase E can be executed by means of folding devices positioned in correspondence with said station but that operate during the phase wherein the conveyor 7 moves to transfer the package 1 to a subsequent pick-up station. In correspondence with the station S is provided a pair of first folding devices 10 positioned above the conveyor 7 at a level slightly higher than the plane whereon the pockets 6 open, and in such a way as to face the sides 4b of the container 4 that reaches the station S. Upstream of the first folding devices 10, and substantially at the same level, is positioned a second folding device 11 movable in transverse direction with respect to the direction of advance of the container 4 towards the station S, from a first position wherein it does not hamper the arrival of the container 4 in the station S, to a second position wherein it is in vertical position and facing (in contact or nearly so) the side 4a of the container 4 which is oriented upstream of said station S. The second folding device 11 is supported so that, in its second position, it can be rotated downwards starting from its vertical position towards the station S. Downstream of the first folding devices 10, according to the present invention, is positioned a folding- pressing device 12. The folding-pressing device 12 is positioned above the conveyor 7, extends on a plane substantially parallel to the conveyor 7 itself and is at a slightly higher level than the plane whereon the pockets 7 open. The folding-pressing device 12 is provided with a heater 13 thereby serving also as a welding device, as shall be described hereafter, and it is supported thereby being able to descend slightly towards the conveyor 7. When a container 4 reaches the station S the first folding devices 10 intervene on its sides 4b and execute phase C as per Figure 2; immediately before said folding devices 10 return to the initial position the second folding device 11 intervenes on the first of the sides 4a, folds it superimposing it to the sides 4b folded previously and remains in its position rotated downwards, executing Phase D as per Figure 2. At this point the conveyor 7 moves forward by one step and the second side 4a of the container 4 is engaged by the heated folding-pressing device 12. The folding-pressing device 12 folds the second side 4a to close the package 1 and simultaneously transmits heat at least to both folded sides 4a, descending in level and pressing thereon. At the start of this phase the active position of the second folding device 11 initially assures the stable superimposition of the first side 4a to the folded sides 4b, position that is stabilised as a result of the action of the heated folding-pressing device 12 which performs at least a sort of pre-heating of the closure of the package 1 executing phase E as per Figure 2. Downstream of the station S and in correspondence with a further stopping station SI of the pocket 6 which at this point contains the defined package 1, a heated pressing device 14 may be provided, according to the present invention, so positioned as to descend towards the package 1 and press on its closure thereby definitively welding it. The pressing device 14 can also serve to extract the package 1 from the closure line of the machine.

The forming hopper 3 may be of the type with dual pit thereby being able simultaneously to form two containers, and hence two packages, for each complete rotation cycle of the turntable. Clearly, in this case for each pit a piston 5 and the pressing means 8 shall be provided. Moreover said turntable shall present multiple pairs of pockets 6, equidistant from pair to pair, with each pair 6 suited to contain a single container 4 exiting said pit of the hopper 3. In correspondence with each operative station S wherein the pairs of pockets come to stop shall be provided corresponding pairs of folding devices and of heated folding-pressing devices, for the simultaneous execution of the closure phases of the containers transported by a pair of pockets.

The example as per Figure 5 reflects the embodiment wherein the conveyor 7 is a continuous linear conveyor. In this case the first folding devices 10, the second devices 11, the heated folding-pressing devices 12 and the heated pressing devices 14 related to each row of n rows of pockets 6 for housing n containers 4 which simultaneously reach the station S and, respectively, the station SI, are supported by common support bars 15 and respectively 16 and 17 positioned transversely above the conveying surfaces of the conveyor 7 whereon the pockets 6 open.

In the case shown in Figure 5 the first folding devices 10, supported by the bar 16 shall initially be rotated in a position of non interference for the passage of the containers 4 towards the station S.

From the above description it is evident that the Applicant, with the solution constituting the object of the present invention, has fully reached the aim and the goal which it had set.

The invention thus conceived in its solution idea can be subject to numerous modifications and variations of the constructive forms of the devices for its realisation, so that all constructive details described above may be replaced with technically equivalent elements.

Claims

1. Package for products of solid or pasty consistency derived from milk and dosed, as well as for pats or small cubes of edible mixtures, characterised in that it comprises a section of plastic material, of the heat-weldable type, folded or shaped into a bag to form an open container whereinto the dosed product is to be placed; the closure of said package being defined by the folding and mutual superimposition of portions or edges of part of the container initially open and subsequently filled, taken to cover the product placed into the container; said mutually superimposed portions or edges being joined together by means of welding following a localised heating of the heat-weldable material that involved at least those closure portions or edges that are last to be mutually superimposed.

2. Method for the realisation of packages of products of solid or pasty consistency derived from miLk, as well as for pats or small cubes of edible mixtures, packages of the type according to claim 1, method wherein an empty container is formed, open at the top starting from a section of plane laminar material, and said container is inserted in a pocket of equal shape and substantially equal cross section, able partially to house said container in correspondence with its part towards the bottom, said pocket being comprised in a conveyor for transferring the container to a filling station and, subsequently, along a closure line of the container itself to form the package, closure line wherefrom the package is extracted, characterised in that it comprises:

- using as a section of laminar material a section of film of heat-weldable plastic material;

- shaping into a bag or folding said section inside a pit-shaped forming hopper, by means of a piston capable of shaping said container in concurrence with the walls of said forming hopper;

- using pressing means, preferably placed at the base of the hopper, to fix, permanently and in concurrence with said piston, one or more folding lines of the bottom and of the sides of the container previously formed in the hopper, in the phase wherein, by means of said piston, the container is inserted into said partial housing pocket, passing through the outlet of said forming hopper.

3. Method according to claim 2, characterised in that for the closure of the package it comprises: folding the portion of the container projecting from the related housing pocket to cover the product placed therein;

- using, for such folding action, a succession of folding devices, positioned along said closure line and with different orientations with respect to the directrix of motion of the conveyor;

- activating said folding devices in phase with the stoppage times of the conveyor and in such a way that a relative motion is effected between folding devices and container housed in said pocket such that successive portions of the container, projecting from said pocket, are folded one over the other;

- activating successive folding devices, with such a mutual phase relation that the first portions of the container folded back are kept in position by the related folding device until a successive portion is folded by a related folding device;

- using heated folding-pressing devices as devices for the final folding and closing of the container;

- obtaining the mutual welding of at least the last portions of the container to be folded to cover the product contained therein by means of the localised heating of said portions and of the pressure exerted thereon by said heated folding-pressing devices.

4. Method according to claim 3, characterised in that it comprises a successive heating phase of the portions of the container folded to close the package by means of heated pressing means that operate downstre.am of said heated folding-pressing devices and that complete, if necessary, the aforesaid welding operation.

5. Devices for the realisation of the package according to claim 1 and for the execution of the method according to claims 2 and 3, usable in automatic machines for the realisation of said package, of the type wherein said conveyor is a turntable or rotating head, and wherein the forming hopper, the device for dosing and dispensing the product, the folding devices, and the devices that extract the package from the closure line, are distributed at the periphery of said turntable in correspondence with stoppage stations of the pockets housing the container; devices that comprise said pit-shaped forming hopper provided with a piston, so shaped as to copy the contour and the inner section of the hopper itself and movable therein, axially and in the two directions, from a first position wherein it is above and outside the inlet of the hopper, to a second position wherein it projects below the outlet of the hopper itself, subsequently to return to the first position, characterised in that said forming hopper is provided, preferably in correspondence with its outlet, with pressing means supported and so positioned as to fix, in a permanent manner and in concurrence with said piston, one or more of the folding lines of the bottom and of the sides of the container realised inside the hopper, in the phase wherein, by means of said piston, the container is made to exit said hopper and is inserted into said pocket of the conveyor.

6. Devices according to claim 5, characterised in that the forming hopper is of the type with dual pit to be able simultaneously to form two containers, and hence two packages, for each complete cycle of rotation of the turntable; in that for each pit a piston and the pressing means according to claim 4 are provided; that said turntable presents multiple pairs of pockets, equidistant between pair and pair, each suited to house a single container exiting said pit of the hopper; in that in correspondence with each operating station wherein the pairs of pockets come to stop are provided corresponding pairs of folding devices; and in that said folding devices comprise heated folding - pressing devices for the simultaneous execution of the closure phases of the containers transported by a pair of pockets.

7. Devices for the realisation of the package according to claim 1 and for the execution of the method according to claims 2 and 3, usable in automatic machines for the realisation of said package, of the type comprising n hoppers, .and at least a pit, forming n containers simultaneously, positioned above a conveyor, of the continuous linear type, equipped with a plurality of pockets uniformly distributed on its transport surface and ordered according to n parallel rows whose mutual distance corresponds to the mutual distance between said forming hoppers, said rows being aligned, on a vertical plane, with corresponding forming hoppers; and where downstream of each forming hopper are provided a device for dosing and dispensing the product, folding devices, and the devices that extract the package from the closure line, distributed above said conveyor in correspondence with stoppage stations of the pockets housing the container; machines wherein each hopper, or for each pit of said hopper, is provided with a piston, so shaped as to copy the contour and the inner cross section of the hopper itself, movable therein, axially and in the two directions, from a first position wherein it is above and outside the inlet of the hopper, to a second position wherein it projects at the bottom from the outlet of the hopper itself, subsequently to return to the first position, said devices being characterised in that they comprise said hopper provided, preferably positioned in correspondence with its outlet, with pressing means supported and positioned in such a way as to fix, in a permanent manner and in concurrence with said piston, one or more of the folding lines of the bottom and of the sides of the container, effected in said hopper, in the phase wherein, by means of said piston, the container is made to exit from said hopper and is inserted into a said pocket of the conveyor.

8. Devices according to claim 7, characterised in that said folding devices comprise heated folding-pressing devices for the simultaneous execution of the closure phases of the containers transported by multiple pockets of said conveyor which reach the stoppage position in correspondence with the station wherein said heated folding- pressing devices are located.