FIELD OF THE INVENTION

The present invention concerns a packing machine, single or multi-line, for loose products which are packed in flexible packages, for example single-dose, i.e. envelopes, made of a packing material of the plastic or heat-coupled type, or of a heat-welded material for packing or packaging, or of a poly-coupled material.

In particular, by loose product we mean a powdered product, granular product or liquid product, but products which in any case are suitable to be contained inside an envelope.

The packing machine can be used individually, or in a production line for making and packing food products or pharmaceuticals or chemical products, in which there is a need to contain a determinate product in suitably metered quantities, suitable for personal consumption.

BACKGROUND OF THE INVENTION

Known packing machines for loose products can form, seal and cut envelopes, and fill them as they are being made. In particular, machines are known which can seal the envelopes on three or four sides.

Known packing machines are provided with a plurality of operating stations: cutting, sealing and guide stations which are provided with one or more cutting, sealing, guide and/or drawing tools for the envelopes.

An example of such packing machines is described in document JP-A- 2012/006607.

It is also known that it is necessary, for example for maintenance and/or when the format of the envelopes is changed, to replace and remove the operating stations from the support frame on which they are attached.

Usually, to install the operating stations on the support frame a plurality of threaded members and/or pins are used. However, this type of connection makes the operations of replacing or removing the operating stations particularly problematic in terms of times and costs of the operators. This also affects the overall packing process, and requires the process to be stopped for long times. Merely by way of example, in document JP-A-2012/006607 cited above, the packing machine comprises a station for welding the envelopes equipped with two rolls located facing each other and counter-rotating. On each roll a welding blade is installed, also called jaw, which extends longitudinally to the axis of the welding roll.

The rolls are supported at the two ends by respective support arms that protrude cantilevered with respect to the support frame. In particular, support blocks are installed on the arms with respective support seatings in which the respective ends of the rolls are positioned and supported.

The support seatings of each block are U-shaped, to allow sliding elements to be inserted inside them, such as bearings, to allow the rolls to rotate.

The sliding elements are therefore integrated with the blocks, and every time a maintenance intervention is required, a lot of time is needed to be able to release the blocks from the seatings and allow to remove the rolls for example.

It should also be noted that the types of connection of the operating stations to the support frame are often subject to damage, both in the connection members themselves and also in the connection portions of the support frame.

It is known for example that some of the operating stations, for example the sealing stations, are heated and are subject to heat dilations. During the replacement operations, this requires long downtimes to prevent burns to the operators on the one hand and, on the other hand, possible damage to the connection members during removal.

The heat stresses to which the connection members are subjected induce plays between the operating stations and the support frame which, if not suitably compensated over time, do not allow a correct packing to be carried out.

Furthermore, due to their configuration, known connection members do not allow to obtain a heat insulation between the operating station, the portion of the support frame that supports it and the connection member itself on which an operator may have to act.

To this must also be added the problems connected to impurities and dirt that are deposited in the connection members and that make the operations to remove them even more complex.

One purpose of the present invention is to obtain a packing machine that simplifies and reduces the times for the operations to maintain the operating stations which require the latter to be removed from the support frame on which they are attached, for example due to a change of format of the envelopes, cleaning and/or replacement of the operating stations themselves.

Another purpose of the present invention is to simplify for the operators the intervention modes on the packing machine.

The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.

SUMMARY OF THE INVENTION

The present invention is set forth and characterized in the independent claims, while the dependent claims describe other characteristics of the invention or variants to the main inventive idea.

In accordance with the above purposes, a machine for packing loose products in an envelope comprises a support frame for one or more operating stations configured to perform at least one of the operations of cutting, sealing, guiding or possibly drawing.

The packing machine according to the invention is able to make the cut in a longitudinal direction, usually vertical, and in a transverse direction, usually horizontal, with respect to the direction of feed of a film, and to perform the sealing on three or four sides of the envelope.

By the term film we mean a packing material of the plastic type, heat-coupled, or a heat welded material used for packing or packaging, or poly-coupled material.

At least one of the operating stations comprises at least a support bar on which one or more tools are installed.

According to the invention, the support frame comprises support arms installed protruding cantilevered and configured to support the support bar.

According to a first solution, the support arms are provided with U-shaped seatings, which are configured to allow the positioning in a correct operating position of a support element provided in the support bar.

According to a second solution, the support bar is provided with U-shaped seatings, which are configured to allow the positioning in a correct operating position of a support element provided in the support arms. In accordance with one aspect of the present invention, for each seating a single interference element is provided, selectively removable and positionable, and configured to constrain the positioning of the support element in the seating.

In this way, by removing only one interference element from each seating, it is possible to replace or remove the support bar without needing to perform complex removal operations of different support, attachment and connection components as happens instead in the state of the art.

Advantageously, the U-shaped seatings allow to position and support the support bar and at the same time allow an easy removal of the individual operating stations, whether they are dedicated to cutting, sealing, guiding and/or drawing.

This solution is also able to thermally insulate the hot parts, that is, the support bar, with respect to the support frame, with consequent limitation and elimination of heat stresses or the creation of play between the various components.

This allows to increase over time the working life of the machine and/or at least some of the operating stations.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other characteristics of the present invention will become apparent from the following description of some embodiments, given as a non-restrictive example with reference to the attached drawings wherein:

- fig. 1 is a lateral view of a packing machine;

- fig. 2 is a perspective view of an operating station for longitudinal sealing;

- fig. 3 is a section view of the operating station for longitudinal sealing in fig. 2;

- fig. 4 is a perspective view of an operating station for transverse sealing;

- fig. 5 is a section view of the operating station for transverse sealing in fig. 4;

- fig. 6 is a perspective view of an operating station for transverse cutting;

- fig. 7 is a section view of the operating station for transverse cutting in fig. 6;

- fig. 8 is a perspective view of an operating station for longitudinal cutting;

- fig. 9 is a detail of a device for longitudinal cutting;

- fig. 10 is a perspective view of a guide operating station associated with the operating station for longitudinal cutting.

To facilitate comprehension, the same reference numbers have been used, where possible, to identify identical common elements in the drawings. It is understood that elements and characteristics of one embodiment can conveniently be incorporated into other embodiments without further clarifications.

DETAILED DESCRIPTION OF SOME EMBODIMENTS

According to the present description and with reference by way of example to fig. 1, the invention concerns a packing machine 10.

The machine 10 during its work cycle is able to produce a plurality of envelopes by sealing and cutting one or two films 20.

In the case of envelopes obtained from a single film 20, this is usually cut vertically to define a plurality of strips. The strips are folded back on themselves in a tubular configuration and joined along the lateral edges by welding. Then, a lower part of the tubular element obtained is welded, the welded tubular element is subsequently filled and the upper part of the tubular element is closed. The tubular element thus obtained is cut to define the envelope.

In the case of envelopes obtained from two films 20, these are supplied facing each other, cut and welded laterally to define a rectangular conformation. Subsequently, the lower part of each envelope is welded so as to fill it with the substance. Finally, the upper part is welded and the envelope containing the substance is cut.

However the envelope is obtained, the machine 10 according to the present invention is provided with a plurality of operating stations configured to carry out at least one of either cutting, sealing, guiding and/or drawing, which are suitably disposed and conformed to obtain one type of envelope or the other.

The configurations/dispositions of the operating stations described here are therefore provided merely by way of non-restrictive example of the application of the present invention.

The machine 10 comprises a support frame 11 on which one or more operating stations are installed, that is, at least one of cutting operating stations 25a, 25b, 25c, sealing operating stations 26a, 26b and a guide operating station 27.

The machine 10 also comprises a feed unit 18 configured to feed the film 20 toward the operating stations 25a, 25b, 25c, 26a, 26b, 27.

The feed unit 18 is suitable to support and supply the film 20, which is initially wound in a reel 19.

The feed unit 18 is configured to feed the film 20 in a predefined path and in a direction of feed F to the operating stations 25a, 25b, 25c, 26a, 26b and 27.

The machine 10 comprises a metering unit 22 configured to deliver the desired product into the envelopes which are produced on each occasion.

The machine 10 comprises, in the configuration of fig. 1, two cutting operating stations 25a, 25b, two sealing operating stations 26a, 26b, a guide operating station 27 and possibly a pre-cutting operating station 25c.

In particular, it is possible to install in the machine 10, in the direction of feed F and in order:

- the cutting operating station 25a, which performs a longitudinal cut, in this case a vertical cut, on the film 20 to obtain strips of a predefined width and coordinated with the width of the envelopes;

- the sealing operating station 26a, which performs a longitudinal seal, in this case a vertical seal, on the strips, to obtain substantially a plurality of tubular elements in which the product is metered;

- the sealing operating station 26b, which performs a transverse seal, in this case a horizontal seal, on the strips of film 20 to seal the tubular element below and above and to obtain a plurality of envelopes;

- the possible pre-cutting operating station 25c, which performs an incision promoting the opening of the envelope;

- the cutting operating station 25b, which performs a transverse cut, in this case a horizontal cut, and reciprocally separates the envelopes and

- the guide operating station 27, which guides and possibly draws the tubular envelopes in the direction of feed F. The guide operating station 27 can possibly be positioned before the cutting operating station 25b, in an intermediate position between the operating stations listed above.

It is quite clear that the machine 10 according to the present invention can provide a different disposition of the operating stations, also according to the particular type of envelope to be obtained.

At least one of the cutting operating stations 25a, 25b and 25c, the sealing operating stations 26a, 26b and the guide operating station 27 comprises at least a support bar 13 on which one or more tools 14 are installed, respectively cutting, sealing and guide tools.

According to possible solutions, which will become clear hereafter in the description, at least some of the operating stations 25a, 25b, 25c, 26a, 26b and 27 can each be provided with at least two support bars 13 installed facing each other and mobile reciprocally toward/away from each other for the cutting, sealing and guide operations.

The support frame 1 1 comprises, in a known manner, support arms 15, installed protruding cantilevered with respect to the support frame 11, and suitable to support at least one support bar 13.

According to a possible solution, each support bar 13 is supported, for example at the ends, by at least a pair of support arms 15.

According to another solution, combinable with the other solutions described here, the support bar 13 is provided with terminal ends 23 which are supported, as described hereafter, by the support arms 15.

The support frame 1 1 has at least one front wall or plate 24, on which all the support arms 15 are installed protruding cantilevered.

According to one aspect of the present invention, the support arms 15 or the support bar 13 are provided with U-shaped seatings 16, each configured to allow to position, in a correct operating position, a support element 17 of the support bar 13, or respectively the support arm 15. For each seating 16, a single interference element 31 is also provided, selectively removable and positionable, and configured to constrain the positioning of the support element 17 in the respective seating 16.

This solution allows to be able to remove/replace the support bar 13 by removing only one interference element 31, without complex operations of removing a plurality of components, as required instead in the state of the art. According to a possible embodiment, the interference element 31 is the threaded type. This makes it extremely quick to remove/replace the support bars 13, and also ensures they are retained securely in the housing seatings 16.

According to possible solutions, the support elements 17 can be defined by pins, bars or support portions.

The support elements 17 can be components integrated in a single body, or separate and independent from the support bar 13 or support arm 15, and subsequently attached to the latter.

According to a first solution, shown in figs. 2-5, the support arms 15 are provided with the seatings 16 with a U-shaped conformation, while the support bar 13 is provided with support elements 17, in this case support pins, positionable in the seatings 16 made in the support arms 15.

According to figs. 3 and 5, the support arms 15 are provided with terminal portions 21, attached cantilevered, and in which the seatings 16 are made. The seatings 16 can be made open upward during use, to receive and support the support element 17 associated with the support bar 13.

According to a possible embodiment, each support arm 15 can be provided with a single seating 16 to support a single end of the support bar 13.

According to a possible embodiment, possibly combinable with the other embodiment described here, the machine 10 comprises a plurality of support bars 13 supported by respective support arms 15. The support bars 13 and the support arms 15 are provided with the seatings 16 and respectively the support elements 17, or vice versa.

According to figs. 2-5, the support elements 17 comprise support pins attached in correspondence with the terminal ends 23 of the support bar 13. The support pins are disposed with their oblong development substantially parallel to the longitudinal development of the support bar 13.

With reference to figs. 2-5, the terminal ends 23 of the support bar 13 are provided with a shaped bracket 39 with a U-shaped conformation and a concavity 28: the support element 17, or pin, is installed in the concavity 28. The U-shaped conformation of the shaped bracket 39 allows to support the support pin at both ends and/or allows to associate gripping elements to facilitate the operators' grip and prevent them from being burnt, for example.

The shaped bracket 39 is installed during use astride the corresponding terminal portion 21 of the support arm 15.

According to possible solutions of the present invention, shown by way of example in figs. 2-5, a single interference element 31 is associated with each seating 16 provided in the support arms 15, to constrain the positioning of the support element 17 provided in the support bar 13, inside the seating 16.

In particular, it can be provided that the interference element 31, during use, at least partly occludes the seating 16, preventing the support element 17, in the case shown, the support pin, from coming out. According to the solution shown in figs. 2-5, the interference element 31 comprises a screw that can be inserted in a threaded hole and positioned with its shaft to at least partly occlude the seating 16.

Figs. 2 and 3 show one embodiment of the sealing operating station 26a configured to perform a longitudinal seal on the envelopes.

In this embodiment, the sealing operating station 26a is provided with a single support bar 13 on which the tools 14 are installed, in this case having a rounded bar conformation, not cutting, which is suitably heated to heat-seal the envelopes. The bars are disposed with their longitudinal development substantially parallel to the direction of feed F.

According to the embodiments shown in figs. 2 and 3, the sealing operating station 26a comprises a contrast element 40 installed in a fixed position on the support frame 1 1 and, in the case shown, in a position facing and more internal with respect to the corresponding support bar 13.

For example, the contrast element 40 can comprise a forming tube 30, which as well as functioning as a contrast also forms the envelopes.

The support bar 13 of the sealing operating station 26a is selectively movable toward/away from the contrast element 40 in order to move the tools 14 to rest against the latter and to define the sealing action of the film 20 interposed between them.

In other embodiments, the contrast element 40 could also be installed on a support bar, as in any of the ways described here.

According to the solution shown in figs. 2 and 3, the support bar 13 is connected to drive devices 29 in order to move the support bar 13 as described above.

According to a possible solution, shown for example in figs. 2 and 3, the drive devices 29 are integrated in the support arms 15 of the support bar 13.

The drive devices 29 can comprise at least a linear actuator 41 with the function of the support arms 15, and installed protruding cantilevered with respect to the support frame 1 1. In particular, the shaft of the linear actuator 41 can function as a support arm 15.

The linear actuator 41 is provided with a mobile shaft at the end of which there is the terminal portion 21. With reference to figs. 4 and 5, the transverse sealing operating station 26b is provided with two support bars 13 disposed facing each other and each provided with a respective tool 14, in this case a sealing bar disposed with its longitudinal development transverse with respect to the direction of feed F.

According to this embodiment, it is provided that each support bar 13 is supported by a respective pair of support arms 15.

A drive device 29 is associated with both the support bars 13, and is provided to move the support bars 13 linearly toward/away from each other, and in a transverse direction with respect to the direction of feed F.

In this embodiment too, it can be provided that the drive devices 29 of the support bars 13 are integrated in the respective support arms 15.

The drive devices 29, in the case shown here, comprise an articulated mechanism, provided with connecting rods, cranks, rods, drive shafts and a drive member, provided to determine the movement of the support bars 13. The articulated mechanism can also be configured to synchronize the movement of the support bars 13.

According to an alternative solution, shown in figs. 6, 7 and 10, the at least one support bar 13 is provided with the seatings 16 with a U-shaped conformation, while the support arms 15 are each provided with a support element 17, in this case integrated in the support arm 15 itself, and suitable to receive and support a support bar 13.

The seatings 16 can be made in correspondence with lateral ends of the support bars 13.

According to these embodiments of the present invention, the support arms 15 can be provided with a terminal support portion 42 which defines the support element 17.

The support bar 13 is associated with the support element 17 by inserting the seatings 16, with a movement from the top downward, onto the terminal support portions 42 of the support arms 15, where they find support. The support bar 13 is removed with an inverse movement.

The interference elements 31, each provided to constrain the positioning of one end of the support bar 13 on the support arm 15, can be associated with the terminal support portions 42. According to a possible solution, the interference element 31 is a threaded nut 32.

According to the solution shown in figs. 6 and 7, the terminal support portion 42 can be provided with a thread on which the threaded nut 32 is screwed.

In this way, by screwing or unscrewing only a pair of threaded nuts 32, it is possible to install or remove a support bar 13 on/from the support frame 11, making these operations extremely quick and easy.

According to possible solutions, all the interference elements 31, for example of the various operating stations of the machine, and associated with the seatings 16, have the same conformation, so that with a single tool it is possible to remove all the support bars 13.

In particular, it can be provided that all the interference elements 31 are each provided with a drive portion on which to act to allow the removal or insertion of the interference element 31 from/into the seating 16. Advantageously, the drive portions of the interference elements 31 can all have a conformation substantially analogous to each other. This feature advantageously allows to standardize the operations to replace the operating stations 25a, 25b, 25c, 26a, 26b and 27, for example using the same tool, possibly associated on board the machine, thus reducing the downtimes of the machine and increasing productivity.

According to other variant embodiments, the interference elements 31 can comprise gripping portions, for example handles, directly drivable by an operator to allow rapid installation and removal of the support bar 13.

Figs. 6 and 7 show the transverse cutting operating station 25b of the envelopes, although an analogous description can also be provided for the pre- cutting operating station 25c.

However, it is quite obvious that, although the installation methods of the support bars 13 are described with particular reference to a specific operating station, the installation methods provided in one operating station can be suitably combined with or replaced by those described for another operating station, to obtain the purposes of the present invention.

According to the solution shown in figs. 6 and 7, the cutting operating station 25b comprises two facing support bars 13, each installed on respective support arms 15. In the solution shown in figs. 6 and 7, one of the support bars 13, in this case the most internal to the support frame 11, is installed on the support arms 15 in a fixed position. In this case the support arms 15 can be defined by screws or threaded bars, installed protruding cantilevered with respect to the support frame 11 or to brackets associated directly or indirectly with the latter.

At least one of the support bars 13, in this case the most external, is associated with at least a drive device 29 provided to move one support bar 13 toward/away from the other.

According to this embodiment too, it can be provided that the drive device 29 is integrated in the support arms 15.

It can be provided, for example, that the support arms 15 are defined by a linear actuator 41, as described above, with the function both of supporting the support bar 13 and also of moving it.

Tools 14 are installed on the support bars 13, which in this case are defined by cutting blades disposed transverse to the direction of feed F.

With reference to the solutions shown in figs. 8 and 9, the longitudinal cutting operating station 25a has at least one support bar 13 installed on the support frame 11, in one or other of the installation methods described above.

One or more cutting tools 14 are installed on the support bar 13.

The tools 14 are installed on support bodies 33, also configured to possibly move and adjust the position of the tools 14 on the support bar 13.

Facing the support bar 13 at least one contrast roll 34 is installed, to determine a contrast against the cutting of the film 20 in a longitudinal direction.

The tool 14 can have a circular shape to achieve with its peripheral edge a longitudinal cutting of the film 20.

The tool 14 can be installed removably on a support element 35 of the support body 33.

The tool 14 is installed rotating on a pin 36 in correspondence with seatings 44 made in the support element 35.

The support body 33 is provided with at least one clamping element suitable to prevent the pin 36 from coming out of the seating made in the support element 35.

Advantageously, the clamping element allows to replace the tool 14 rapidly, reducing machine downtimes.

For example, the clamping element can be made from a fork element, which can be inserted with its prongs in corresponding holes made in the support element 35 and which intercept the seatings 44. In particular, the prongs of the fork element occlude the aperture of the seatings 44, constraining the pin 36 inside them.

According to a variant embodiment, shown in fig. 9, magnetic elements 45 are associated in the seatings 44, configured to attract and hold the pins 36 magnetically inside the seatings 44. The magnetic elements can be installed on the bottom of the seating 44 in a position opposite the aperture defined thereby.

In this way, together with an operation to insert the pin 36 into the seating 44, a correct positioning of the tool 14 is obtained with respect to the support element 35. The contrasting action of the contrast roll 34 ensures that the pin 36 is kept in the seatings 44 during working.

The support body 33 comprises a pneumatic drive member 38 configured to determine the movement of the tool 14 in a perpendicular direction with respect to the surface of the contrast roll 34.

The pneumatic drive member 38 allows to obtain greater control and precision in the pressure exerted by the tool 14 on the film 20.

With reference to fig. 10, a possible variant embodiment is shown to the cutting operating station 25a, which is provided with a support bar 13 configured to support a plurality of tools 14, in this case fixed cutting blades.

The support bar 13 is equipped with a plurality of tool-holders on which the tools 14 are fixed.

The support bar 13 is installed with respect to the support frame 11 on the support arms 15 as described above with reference to figs. 6 and 7.

The tools 14 act on the film 20 to cut it, and cooperate with respective contrast elements, in this case contrast rolls, installed facing the tools 14. The contrast elements in this case are installed on a rotation shaft substantially parallel to the support bar 13.

Fig. 10 also shows a drawing operating station 27 which is installed downstream of the cutting operating station 25a.

The drawing operating station 27 comprises a drive shaft 46 on which at least one drawing roll is installed, in this case a plurality of drawing rolls 48.

The drive shaft 46 is connected to a motor 47 that makes the latter rotate, and in the case shown here also the rotation shaft on which the contrast elements of the cutting operating station 25a are installed.

The drawing operating station 27 also comprises tools 14, in this case with a contrast/guide and drawing function, which are installed on a support bar 13 located facing the drive shaft 46.

The tools 14 in this case comprise presser rolls, possibly rubberized, which during use press against the drawing rolls 48, causing the films 20 in transit between them to advance.

The presser rolls are installed idle on the support bodies which in turn are attached to the support bar 13.

The support bar 13 is attached to support arms 15 according to methods substantially analogous to those described above with reference to figs. 6 and 7. It is clear that modifications and/or additions of parts may be made to the machine 10 as described heretofore, without departing from the field and scope of the present invention.

It is also clear that, although the present invention has been described with reference to some specific examples, a person of skill in the art shall certainly be able to achieve many other equivalent forms of machine 10, having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby.