DESCRIPTION

The invention relates to a packaging machine for forming doy-pack bags.

Nowadays, self-supporting sealed pouches for product packaging are increasingly present on the market, particularly in the large-scale retail trade, which sealed pouches are made from a single piece of folded and welded packaging band.

Such a sealed pouch, known in jargon as a ‘doy-bag’ or ‘doy-pack’ pouch, has a bottom surrounded by lower supporting rest edges, two walls, joined one to the other laterally through the respective side edges, and an upper edge, normally designed to be opened for the fruition of the product contained in the pouch.

Generally, a vertical forming group is used for the realization of this type of pouches and comprises:

- a packaging band made of a plastic material;

- a shell for the deviation and shaping of the band, for the realization of a sealed pouch, from an inlet direction with an extended conformation to an outlet direction with a tubular conformation, and a shaping collar, placed to surround a forming tube and adapted to deviate the band being processed towards the forming tube;

- a forming tube, for the descent of material to be introduced into a pouch being made, which forming tube has a rear face thereof turned towards the side of the one or more approach rollers, and a front face, opposite to the rear face;

- first means for the arrangement to the mutual joining of a first pair of longitudinal portions of band, for the realization of an upper edge of a pouch in arrangement of use;

- and second means for the arrangement to the mutual joining of a second pair of longitudinal portions of band and of a third pair of longitudinal portions of band, for the realization of two corresponding side-by-side lower edges supporting the rest bottom of a pouch in arrangement of use, on the opposite side of the pouch with respect the upper edge.

The packaging band is normally a multilayer film made of plastic material.

This band is moved by means of tracks, belts or rollers placed on the sides of the forming tube, in an area underneath the shell, which tracks are adapted to press corresponding portions of the band against the forming tube to drag it downwards.

The completed sealed pouch finally drops to an underlying collection and handling means, such as a conveyor belt.

Such a forming group is obviously suited to industrial production, designed for large numbers, whereas nowadays the flourishing of small and medium-sized activities, often of a craft nature, capable of small numbers but with a high variety of products, requires more versatile and at the same time more economical machinery and equipment.

In addition, forming groups such as the one described above have the drawback of being able to work only and exclusively with tapes made of plastic material, where today there is an increasing need, driven by national and international legislation, to eliminate the use of plastics, particularly in the food industry.

In fact, known forming groups require the plastic band to be folded and placed under traction at angles, pressures and forces that a film made of paper material would not be able to withstand and would quickly tear.

The task of the present invention is to develop a packaging machine for forming doy-pack bags capable of overcoming the aforementioned drawbacks and limits of the prior art.

In particular, one object of the invention is to develop a packaging machine capable of operating with films or sheets of paper material.

Another object of the invention is to develop a highly versatile packaging machine.

A further object of the invention is to develop a packaging machine that is less complex and therefore less expensive than a known type of forming group.

Still, an object of the invention is to develop a compact packaging machine, that is, with a smaller footprint than that of a forming group of known type, which can therefore be easily set up inside a craft laboratory such as the one inside a bakery, a pastry shop or a pasta factory or the like.

The above-mentioned task and purposes are achieved by a packaging machine for forming doy-pack bags according to claim 1 .

Further characteristics of the packaging machine according to claim 1 are described in the dependent claims.

The aforesaid task and objects, together with the advantages that will be mentioned hereinafter, are indicated by the description of an embodiment of the invention, which is given by way of non-limiting example with reference to the attached drawings, where:

- Figure 1 represents a schematic perspective view of the packaging machine according to the invention;

- Figure 1A represents a schematic side view of a portion of the packaging machine according to the invention;

- Figure 2 represents a schematic perspective view of a first operating step of the packaging machine according to the invention;

- Figure 3 represents a schematic perspective view of a second operating step of the packaging machine according to the invention;

- Figure 4 represents a schematic perspective view of a third operating step of the packaging machine according to the invention;

- Figure 5 represents a schematic perspective view of a fourth operating step of the packaging machine according to the invention;

- Figure 6 represents a schematic perspective view of a fifth operating step of the packaging machine according to the invention;

- Figure 7 represents a schematic perspective view of a sixth operating step of the packaging machine according to the invention;

- Figure 8 represents a schematic perspective view of a seventh operating step of the packaging machine according to the invention;

- Figure 9 represents a broken perspective view of a doy-pack bag made with a packaging machine according to the invention;

- Figure 10 represents a detail of the packaging machine according to the invention;

- Figure 11 represents a perspective view of a variant embodiment of a detail of the packaging machine according to the invention;

- Figure 12 represents a schematic sectional view of the detail of Figure 11 ;

- Figure 13 represents a schematic view of a packaging sheet used in the packaging machine according to the invention;

- Figure 14 represents a schematic view of a sheet-holding reel used in the packaging machine according to the invention.

With reference to the above-mentioned figures, a packaging machine for forming doy-pack bags according to the invention is indicated as a whole with number 10. This packaging machine 10 for forming doy-pack bags comprises:

- a base 11 ;

- a reel-holding frame 12, configured to carry a reel of a packaging film or a sheet-holding reel 13, the latter comprising a band on which packaging sheets 14 are fixed in a removable manner, as more fully described below and as exemplified in Figure 14;

- a gripping and folding group 15 configured to pick up and fold like a book, by facing two symmetrical parts 14a and 14b thereof, either a portion of a packaging film or a packaging sheet 14, the latter being well exemplified in Figure 13;

- pushing means configured to shape an intermediate section 14c of the portion of film of the packaging sheet 14 in such a way that said intermediate section 14c folds by arranging itself between the two symmetrical parts 14a and 14b arranged facing each other, said pushing means thus defining a recessed bottom B of a doy-pack bag A, the latter schematically shown in the broken perspective view of Figure 9; the pushing means are supported by corresponding handling means 17, schematically shown in Figure 1 , configured to move the same pushing means either towards a packaging film or towards a packaging sheet 14 when the latter is retained by the gripping and folding group 15, as highlighted in Figure 6;

- joining means 18 and 118 for sealing the facing side edges C1, C2, C3, C4 of said two symmetrical parts 14a and 14b either of a portion of the packaging film or of the packaging sheet 14;

- pick-up means 19, configured to remove the portion of the packaging film or of the packaging sheet 14, folded and with the facing side edges C1, C2, C3, C4 sealed, from the gripping and folding group 15, as schematically shown in Figure 8.

In the figures, an embodiment of the packaging machine 10 according to the invention in which a sheet-holding reel 13 is present is exemplified, but the variant embodiment in which a reel of a packaging film is used is obviously also to be understood as being part of the invention.

In the present embodiment, the pushing means comprise a shaping punch 16 for shaping a recessed bottom B of a doy-pack bag A, the latter schematically shown in the broken perspective view of Figure 9.

The shaping punch 16 is supported by corresponding handling means 17, schematically shown in Figure 1 , configured to move said shaping punch 16 either against a packaging film or against a packaging sheet 14 when the latter is retained by the gripping and folding group 15, as highlighted in Figure 6.

In an alternative embodiment of the packaging machine according to the invention, not illustrated for simplicity’s sake, the pushing means comprise a pressurized fluid ejection device configured and positioned to push the intermediate section 14c of said portion of film or of said packaging sheet 14 by means of an ejected fluid, so that said intermediate section 14c folds by arranging itself between the two symmetrical parts 14a and 14b arranged facing each other.

Again by way of example, such a pressurized fluid ejection device may be an air compressor, or another device for emitting a gaseous fluid.

Again by way of example, such a pressurized fluid ejection device may be a pump for water, or another device for emitting a liquid.

In the present non-limiting embodiment of the invention, the reel-holding frame 12 comprises:

- a supporting structure 20, for example fixed to the base 11 ;

- a reel-holding shaft 21 at one end of the supporting structure 20, for example at the upper end;

- a scrap collection reel 22 at the opposite end of the supporting structure 20;

- blocking means configured to stop either a portion of the packaging film or a portion of band 13a of a sheet-holding reel 13 at a packaging sheet 14, said blocking means being arranged between said reel-holding shaft 21 and said scrap collection reel 22, and being positioned facing the gripping and folding group 15.

In the present embodiment, the blocking means comprise a suction table 23, provided with suction holes and corresponding suction ducts for retaining the band 13a of the sheet-holder reel 13 against it.

The suction is performed by a suction pump 24 connected to this suction table 23 with a corresponding pneumatic line 24a, as schematically exemplified in Figure 1A.

The suction table 23 is adapted to block the band 13a when a packaging sheet 14 is positioned facing the gripping and folding group 15, as better described below.

This gripping and folding group 15 comprises: - two folding plates 25 and 26, a first upper plate 25 and a second lower plate 26, with suction holes for gripping a portion of a packaging film or a packaging sheet 14;

- means 27 of opposing roto-translation of the folding plates 25 and 26 from a co-planar arrangement thereof for gripping a portion of the packaging film or a packaging sheet 14, depicted in Figures 1 to 5, to an arrangement in which the folding plates 25 and 26 are facing and under pressure one on the other at least at the side edges 25b, 25c, 26b, 26c of the same folding plates 25 and 26, as shown in Figures 6 and 7;

- suction means 30 configured for suction from the folding plates 25 and 26.

The suction means 30, for example, comprise the suction pump 22, a second pneumatic line 24b for the suction from the first upper folding plate 25, a third pneumatic line 24c for the suction from the second lower folding plate 26, and corresponding suction holes defined at least on the side edges 25b, 25c, 26b, 26c of the same folding plates 25 and 26, but possibly also in other areas of said folding plates 25 and 26.

The means of opposing roto-translation 27 comprise, for example, a belt 46 between a motorised pulley 47a and an idler pulley 47b, wherein a first branch 46a of the belt 46 is fixed to the motorised pin 48a of the upper plate 25, and a second branch 46b of the belt 46 is fixed to the motorised pin 48b of the lower plate 26.

The synchronisation and coordination of the motors driving the belt 46 and the motorised pins 48a and 48b result in the roto-translational movement of the folding plates 25 and 26.

The packaging machine 10 comprises relative handling means 35 configured to bring said gripping and folding group 15, with said folding plates 25, 26 in co-planar gripping arrangement, closer to said reel-holding frame 12.

In the present embodiment, said relative handling means 35 are configured to translate the reel-holding frame 12 alternately towards and away from the gripping and folding group 15.

In particular, and still by way of example, such relative handling means 35 comprise a movable slide 51 placed to slide on the base 11 and driven by a belt system 52 with a gear motor 53, as exemplified in Figure 1 .

In the present embodiment, the packaging machine 10 comprises a sheetholding reel 13. The reel-holding frame 12 also comprises translation means for the scrap collection reel 22 and for the suction table 23, which are configured to move said scrap collection reel 22 and said suction table 23 in such a way that, when a packaging sheet 14 is blocked by the folding plates 25 and 26, the band 13a of the sheet-holding reel 13 is separated from the packaging sheet 14 itself.

Each packaging sheet 14 comprises two adhesive strips 45a and 45b, clearly visible in Figure 13, each defined on one of the side edges C1, C2, C3, C4 of the two symmetrical parts 14a, 14b of the packaging sheet 14.

These adhesive strips 45a and 45b cause the packaging sheet 14 to be joined with the transport band 13a.

A packaging sheet 14 is then blocked by the folding plates 25 and 26 and moved away from the band 13a.

The translation means comprise a movable body 61, schematically shown in Figure 1 , driven vertically by means of a belt system 62 provided with a gear motor 63.

Such a belt system 62 may comprise one or more belts.

The movable body 61 is fixed to the belt, or belts, by means of corresponding connecting elements.

The shaping punch 16 comprises a wedge-shaped head 16a and a stem 16b supporting said wedge-shaped head 16a.

The shaping punch 16 is intended to be able to have a disc-shaped head, or a head of another similar and technically equivalent shape.

The handling means 17, for example for handling the shaping punch 16, comprise a linear actuator 40 configured to translate said stem 16b so that the wedge-shaped head 16a is arranged in the interspace between the facing inner edges 25a, 26a of said two folding plates 25 and 26, as in Figure 6.

The shaping punch 16 is configured to operate with thrust on an intermediate section 14c of the portion of film or of a packaging sheet 14, so that said intermediate section 14c is recessed between two symmetrical parts 14a and 14b of the packaging sheet 14 for defining a recessed bottom B of a doy-pack bag A, as visible in Figures 6 and 9.

In the present embodiment, the joining means 18 comprise:

- the folding plates 25 and 26;

- the means 27 of opposing roto-translation of the folding plates 25 and 26 from a co-planar arrangement thereof for gripping a portion of a film or a packaging sheet 14, to an arrangement in which the folding plates 25 and 26 are facing and under pressure one on the other at least at said side edges 25b, 25c, 26b, 26c;

- an adhesive strip 45a, 45b defined on at least one of two facing side edges C1, C2, C3, C4 of the two symmetrical parts 14a, 14b.

The adhesive strips 45a and 45b cause the mutual fixing of the two symmetrical parts 14a and 14b of the packaging sheet 14.

In an alternative embodiment, wherein the packaging machine comprises a reel of packaging film, for example made of plastic material, the joining means 118, schematically shown in Figures 11 and 12, comprise two sealing plates 118a and 118b, provided with toothed and heated sidewalls, configured to cause the sealing of the facing edges C1 and C2 and C3 and C4 of a folded portion of film.

The packaging machine 10 according to the invention may further comprise an anti-sealing insert 70, configured to be interposed between the two facing upper edges A1 and A2 of a doy-pack bag A being made, to prevent them from sealing against each other; said anti-sealing insert 70 is exemplified in Figure 10.

Said anti-sealing insert 70 is supported and handled by handling means configured to bring it between the two upper edges A1 and A2 in the step of closing the folding plates 25 and 26; said handling means are intended to be able to be of a type known per se, for example similar to the handling means 71 defined below in the context of the description of the pick-up means 19.

The pick-up means 19 comprise a gripper 50 and corresponding handling means 71 for the gripper 50 between an advanced operating arrangement, as shown in Figure 8, and a retracted rest arrangement, as in Figure 1 .

Such handling means 71 comprise, for example, a belt or band system 72 with a gear motor 73, on which belt system a support 74 for the gripper 50 is mounted.

The object of the invention is also intended to be a method of use of a packaging machine 10 as described above for forming a doy-pack type bag, characterized in that it comprises the following operating steps:

- a first step of defining a portion of a packaging film or preparing a packaging sheet 14 taken from a corresponding reel (Figures 1 , 1 A and 2);

- a second step of folding into two said portion of film or said packaging sheet 14, with definition of two symmetrical parts 14a, 14b which are facing, with a simultaneous pushing operation, on an intermediate section 14c, of said portion of film or of said packaging sheet 14, in order to be recessed between said two symmetrical parts 14a, 14b for the definition of a recessed bottom B of a doy-pack bag A; said second step is schematically shown in Figures 6 and 7;

- a third step of sealing the facing side edges C1, C2, C3, C4 of said two symmetrical parts 14a, 14b; this third step is exemplified in Figures 7, 11 and 12.

Between the first and second steps there is provided an intermediate step of gripping a portion of a packaging film, or a packaging sheet 14, by the gripping and folding group 15.

In particular, the packaging sheets 14 are made of paper material.

Again in particular, and by way of example, such packaging sheets 14 are made of paper material for food packaging.

The particular use of a sheet-holding reel, said sheet-holding reel 13 being of the type comprising a supporting band 13a on which a series of packaging sheets 14 are fixed in a removable manner, in a packaging machine 10 as described above, as well as in a method of use of a packaging machine 10 for forming a doy-pack type bag as described above, is also intended to be an object of the invention.

In particular, the packaging sheets 14 may be made of paper material.

It is also intended to form an object of the invention a sheet-holding reel 13, comprising a supporting band 13a to which a series of packaging sheets 14 are fixed in a removable manner, wherein the packaging sheets 14 are made of paper material.

The supporting band 13a is intended to be of plastic material.

Alternatively, the supporting band 13a is made of paper material.

Practically, it has been established that the invention achieves the intended task and objects.

In particular, the invention has developed a packaging machine capable of operating with films or sheets of paper material.

In addition, the invention has developed a highly versatile packaging machine. In addition, the invention has developed a packaging machine that is less complex and therefore less expensive than a forming group of known type. Furthermore, with the invention a compact packaging machine has been developed, that is, with a smaller footprint than that of a forming group of known type, which can therefore be easily set up inside a craft laboratory such as the one inside a bakery, a pastry shop or a pasta factory or the like.

The invention thus conceived is susceptible of numerous modifications and variants, all of which are within the scope of the inventive concept; moreover, all the details may be replaced by other technically equivalent elements.

In practice, the components and materials used, as well as the dimensions and shapes, as long as they are compatible with the specific use, can be any according to requirements and the state of the art.

If the characteristics and techniques mentioned in any claim are followed by reference signs, these reference signs are to be intended for the sole purpose of increasing the intelligibility of the claims and, consequently, such reference signs have no limiting effect on the interpretation of each element identified by way of example by these reference signs.