Unit for packaging article containing infusion product

A unit (100) for packaging articles (1) containing a product for infusion, preferably filter paper coffee pods (1), is of the type comprising at least one operating stacking station (8) for stacking the pods (1) in such a way as to form at least one stack (1a, 1b) of pods (1). The stacking station (8) comprises a device (9) for handling the pods (1) which guides and controls the stack (1a, 1b) of pods (1) as it is fed into a respective bag-like packet (11).

CROSS REFERENCE TO RELATED APPLICATION

This application is a National Stage entry of International Application No. PCT/IB2005/003982 filed Dec. 14, 2005, which claims priority of Italy Application Number BO2004A000785 filed Dec. 20, 2004, the entire specification, claims and Drawings of which are incorporated herewith by reference.

TECHNICAL FIELD

The present invention relates to a unit for packaging articles containing a product for infusion.

In particular, the invention is advantageously used to package stacked groups of single-use pods of filter paper containing measured quantities or charges of infusion product such as tea, barley coffee, chamomile and the like, preferably powdered coffee, in bag-like packets to which this specification expressly refers but without thereby restricting the scope of the invention.

BACKGROUND ART

Usually, an automatic machine for making filter-paper pods, containing doses of infusion product comprises a production line having a plurality of operating stations located one after the other along it and at the end of which a continuous strip of pods, that is to say, two superposed webs of filter paper heat sealed to each other and having interposed, at regular intervals, a plurality of infusion product charges, is divided up at a cutting station into individual single-use pods separated by waste material.

Downstream of the cutting station, the pod making machine has an end outfeed station equipped with pick and place means designed to pick up the pods one by one and place them on conveyors that transport them to packaging devices which wrap them in respective heat-sealed overwraps. In another solution, which this invention specifically refers to, the outfeed station comprises conveyor means for advancing the groups of pods, preferably stacked, towards packaging units where the groups of pods are picked up and fed by complex mechanical devices into forming assemblies which pack them in packages such as, for example, bag-like packets.

In other words, packaging the groups of pods requires conveyor means for handling and moving the pods from the machine that makes them to the bagging units which, in some cases, may be located some distance away.

A structure of this kind has considerable disadvantages due not only to the presence of the conveyor means required to transport the grouped pods to the packaging units, which greatly increase the overall dimensions of the pod making machine that mounts them, but also and above all to the complexity of the mechanical structural components of the packaging units themselves.

Other major difficulties are caused by the handling and positioning of the pod stacks since the pods are gravity fed into the bags in an uncontrolled manner leading to their being incorrectly arranged in the bags.

The aim of this invention is to provide a pod packaging machine that is free of the above mentioned disadvantages.

DISCLOSURE OF THE INVENTION

This invention accordingly provides a unit for packaging articles containing a product for infusion, of the type comprising at least one operating stacking station for stacking the articles in such a way as to form at least one stack of articles; the unit being characterised in that the stacking station comprises a device for handling the articles which guides and controls the stack of articles as it is fed into the bag-like packet.

With reference to the accompanying drawings, in particularFIGS. 1 and 2, the numeral100denotes in its entirety a packaging unit according to the invention which is mounted on a machine for making articles, especially pods1of filter paper containing powdered coffee and which is designed to package the pods in groups in bag-like packets.

The pod1, in this non-restricting embodiment of the invention, is of well-known type, comprising two lengths2and3of filter material placed face to face and joined to each other by sealing round the edges after a charge4has been placed on the surface of only one of the lengths to form the pod1.

The pod making machine, labeled5as a whole inFIGS. 1 and 2, is of the type comprising a plurality of operating stations located in succession along a production line A extending in a substantially horizontal direction. More specifically, the machine5comprises: a plurality of operating stations for arranging the pods1in their final configuration, consisting of at least one continuous strip S obtained by superposing two webs of filter material with charges4of infusion product interposed and distributed at regular intervals; an operating station6where the two superposed webs are sealed to each other to form the strip S, and where the strip S itself is subsequently cut at least in the area surrounding each charge4to make individual pods1; and a station7for separating the individual pods1from waste material or trimmings S1of the strip S itself.

The separating station7comprises a pusher element7alocated downstream of the station6and designed to push the individual pods1vertically under the feed table50.

The separating station7also comprises a unit7bfor expelling the waste trimmings S1downstream of the pusher7awith respect to the production line A.

As illustrated inFIGS. 1 to 4, the unit100comprises a stacking operating station8for making up stacks1a,1bwith the pods1made by the machine5, and a handling device9for guiding each made up stack1a,1bof pods1into a bag-like container11.

The device9comprises means10,17for guiding the stacked pods1along a vertical feed path section Z towards an end11aof the packet11positioned at the bottom end9aof the device9itself.

As clearly shown inFIGS. 8 to 12, the section Z is parallel to a stacking axis Z1of the pods1at the station8.

During use, the device9(FIGS. 3 and 4), besides guiding the pod1stacks1a1bas they are fed down into the bag-like packet11, also defines surfaces for forming the packet11itself.

As shown inFIGS. 1 and 2, the station8further comprises means12for conveying and positioning the stacks1a,1bof pods1on the device9.

Preferably, the conveying means12consist of a carriage-like bucket12areciprocatingly mobile along a horizontal path T transversal to the direction of the line A (FIGS. 1 and 2, andFIGS. 10 to 12) or, alternatively, conveyor belts combined with guides and pushers capable of transporting the stack or stacks1aand1bto be packaged.

As shown inFIGS. 1 to 4, the guide and controlled downfeed means10,17comprise a vertical channel13consisting of a hollow element14located in the vicinity of the stacking station8(that is to say, at the side or front of the station8), the channel13having an inside section that defines at least one area15,16for the passage of the pods1; and a pod1pushing/accompanying element17located above the hollow element14and mobile vertically along the channel13in such a way that the pods1interfere with the channel13, and thereby guiding and pushing the pods1into the bag-like packet11.

The pusher element17moves between an idle position where the element17is away from the inlet opening at the top of the hollow element14(FIGS. 1,2and3), and a working, pod1guiding and pushing position where the element17slides along the inside of the channel13so as to position the pods1in the bag-like packet11.

In practice, the pusher element17is designed to accompany the pods1and to push them all the way into the bag-like packet11.

As better shown inFIG. 6, since each pod1is substantially disc-shaped, with a defined diameter D1, the cross sectional profile of the channel13of the hollow element14defines at least two adjacent circular zones15and16, with a binocular-like shape to permit simultaneous guided downfeed of two side-by-side stacks1aand1bof pods1.

FIG. 6also shows that the two circular zones15and16for access by the pod1stacks1aand1bhave a diameter D that is smaller than the diameter D1of the pods1so as to control the pods1more effectively as they are pushed down along the channel13.

Obviously, to be able to correctly control downfeed, the diameter D of the zones15and16is just a little smaller than the diameter D1of the pods1, taking into account the outer ring1cof the pod1(surrounding the central portion defined by the coffee charge4) formed by the superposed webs of filter paper which are flexible and easily deformed when the stacks1aand1bare pushed into the channel13but creating just enough interference (as shown by the detail view ofFIG. 5) to prevent the pods1from falling in an uncontrolled manner down the channel13.

As illustrated inFIGS. 6 and 7, the hollow element14is equipped with a longitudinal conduit18for conveying a fluid or inert gas (for example, nitrogen) positioned centrally between the two circular zones15and16, and leading into at least one bottom opening19through which the fluid itself is fed into the hollow element14: thus, the inert fluid is blown onto the pods1as to prevent damage to the pods1as they move down into the packet11(arrows F19,FIG. 7).

For better and more even distribution of the fluid, the longitudinal conduit18leads into at least two opposite openings19and20, one for each of the circular zones15and16. The fluid flow is directed from the bottom up in the channel13.

Further, each circular zone15and16has radial grooves60around its circumference extending for the full length of the circular zones15and16to enable air to escape in the direction opposite the downward direction of motion of the stacks1a,1btowards the packet11.

The other component of the device9is the aforementioned pushing/accompanying element17which comprises a flat head17adesigned to come into contact with the pods1so as to push and guide the pods down the circular zones15and16. The head17ais preferably two-lobed to allow two stacks1aand1bof pods1to be pushed simultaneously (FIG. 2).

The head17ais also associated with a vertical rod21that slides along guides22associated with a vertical column23located above the hollow element14.

The rod21is preferably driven by a variable-speed motor24(for example, a brushless motor) positioned at the top end of the column23(seeFIG. 3) which moves it between the aforementioned idle and working positions.

At the lower end9aof the hollow element14, there is a sealing and cutting device25designed to close the inlet opening11aof the bag-like packet11and to simultaneously form the base11bof the next packet11being formed around the hollow element14(FIG. 4andFIG. 8).

Below is a description of how the packaging unit100according to the invention works.

Once the stacks1a,1bof pods1have been made in the stacking station8, the stacks1aand1b(defining the final quantity and arrangement to be accommodated in the packet11) are transferred along T to the device9.

At this point, the pair of stacks1aand1bare pushed downwards in guided manner along the vertical channel13by the element17(arrow F17C,FIGS. 3 and 4) until the stacks1aand1bare fully inside the bag-like packet11.

Once the stacks1a,1bare inside the packet11, the pushing/accompanying element17can move back up (arrow F17B,FIG. 4) and the top end11aof the bag-like packet11sealed.

A packaging unit structured as described above therefore achieves the aforementioned aims thanks to two simple elements for positioning and controlling the downfeed of the pods and permitting accurate and steady placement of the pods, all in an extremely compact structure.

The solution according to the invention offers several advantages such as, for example, a reduction in the space required for transit between the area where the pods are made and the area where they are packaged, making it possible to integrate the packaging station into the pod making machine, an overall reduction in the number of working parts and stations making up the packaging station, thereby lowering the production cost of the machine as a whole, while at the same time allowing higher operating speeds to be achieved. Moreover, the packaging unit according to the invention makes it possible to significantly increase obtainable packaging speeds because the pod stacks are pushed down into the bags at a higher speed than can be achieved by gravity alone.

It will be understood that the invention as described herein can be modified and adapted in several ways without thereby departing from the scope of the inventive concept. Moreover, all the details may be substituted by technically equivalent elements.