APPARATUS

TECHNICAL FIELD

The present invention relates to a folding apparatus for folding semi-finalized packs of a pourable product, preferentially a pourable food product, into finalized packages of the pourable product, preferentially the pourable food product.

Advantageously, the present invention also relates to a packaging machine for packaging a pourable product, preferentially a pourable food product, into finalized packages and having a folding apparatus for folding semifinalized packs into the finalized packages.

BACKGROUND ART

As is known, many liquid or pourable food products, such as fruit juice, UHT (ultra-high-temperature treated) milk, wine, tomato sauce, etc., are sold in packages made of sterilized packaging material.

A typical example is the parallelepiped-shaped package for pourable food products known as Tetra Brik Aseptic (registered trademark) , which is made by sealing and folding a laminated packaging material. The packaging material has a multilayer structure comprising a carton and/or paper base layer, covered on both sides with layers of heat-seal plastic material, e.g. polyethylene. In the case of aseptic packages for long-storage products, the packaging material also comprises a layer of oxygenbarrier material, e.g. an aluminum foil, which is superimposed on a layer of heat-seal plastic material , and is in turn covered with another layer of heat-seal plastic material forming the inner face of the package eventually contacting the food product .

Packages of this sort are normally produced on fully automatic packaging machines .

There are known packaging machines that advance a web of packaging material through a sterili zation apparatus for sterili zing the web of packaging material and into an isolation chamber in which the sterili zed web of packaging material is maintained and advanced . During advancement of the web of packaging material within the isolation chamber, the web of packaging material is folded and sealed longitudinally to form a tube , the tube being further fed along an (vertical ) advancing direction . In order to complete the forming operations , the tube is filled with a pourable product , in particular a pourable food product , and is transversally sealed and subsequently cut along equally spaced transversal cross sections within a pack forming unit of the packaging machine during advancement along the advancing direction . Pillow packages are so obtained . These pillow packages define sealed semi- finali zed packs having each a central main body, two sealing fins resulting from the transversal sealing and cutting of the tube and protruding from the respective central main body and a plurality of flaps laterally protruding from the central main body . In order to obtain the finali zed packages , the pillow packages are further formed and the sealing fins and the flaps are folded and sealed onto the respective central main bodies .

A typical packaging machine of this type comprises :

- a forming apparatus configured to form the semifinali zed packs being filled with the pourable product ; and

- a folding apparatus configured to receive the semifinali zed packs from the forming apparatus and to form the finali zed packages from the semi- finali zed packs .

A typical folding apparatus comprises an infeed conveyor, which is configured to receive the semifinali zed packs from the forming apparatus and to feed the semi- finali zed packs to a folding unit of the folding apparatus , the folding unit being configured to fold the semi- finali zed packs into the finali zed packages .

There is known a type of folding unit that comprises a plurality of retaining pockets configured to retain the semi- finali zed packs and a conveying device configured to intermittently advance the retaining pockets along an endless path and through a receiving station, at which the semi- finali zed packs are fed into the retaining pockets and a release station at which the finali zed packages are released .

The folding unit also comprises a fixed flap folding device arranged at a treatment station interposed between the receiving station and the release station and configured to simultaneously fold the flaps onto the respective central main body . Thereby, the flap folding device also folds the sealing fins .

Moreover, the folding unit also comprises a thermal treatment device arranged at a thermal treatment station interposed between the treatment station and the release station and configured to thermally treat the flaps and/or portions of the respective central main bodies so as to seal the flaps onto the respective central main bodies .

Even though the known folding apparatuses , in particular the known folding units , work satis fyingly well , there is a need felt in the sector to further improve the known folding apparatuses , in particular the known folding units .

DISCLOSURE OF INVENTION

It is therefore an obj ect of the present invention to provide an improved folding apparatus .

It is an even further obj ect of the present invention to provide an improved packaging machine .

According to the present invention, there is provided a folding apparatus according to the independent claim .

Preferred embodiments are claimed in the dependent claims .

According to the present invention, there is also provided a packaging machine according to claim 16 .

BRIEF DESCRIPTION OF THE DRAWINGS

A non-limiting embodiment of the present invention will be described by way of example with reference to the accompanying drawings , in which :

Figure 1 is a schematic view of a packaging machine having a folding apparatus according to the present invention, with parts removed for clarity;

Figures 2 is a schematic representation of the transformation of a semi-finalized pack into a finalized package, with parts removed for clarity;

Figures 3a and 3b are enlarged perspective views of a detail of the folding apparatus of Figure 1, with parts removed for clarity;

Figures 4a to 4c are enlarged side views of a detail of the folding apparatus of Figure 1 with a portion being in different configurations, with parts removed for clarity;

Figures 5a to 5c are enlarged perspective views of a further detail of the folding apparatus of Figure 1 when being in different configurations, with parts removed for clarity; and

Figure 6 is a perspective view of a further portion of the folding apparatus of Figure 1, with parts removed for clarity.

BEST MODES FOR CARRYING OUT THE INVENTION

Number 1 indicates as a whole a packaging machine for producing, preferentially sealed, finalized packages 2 of a pourable product, preferentially a pourable food product such as pasteurized milk, fruit juice, wine, tomato sauce, yoghurt, milk drinks, yoghurt drinks, emulsions, beverages with pulp, salt, sugar and the like.

Preferentially, packages 2 may be formed from a multilayer packaging material. Even more preferentially, packages 2 may be formed from a web of packaging material 3.

More specifically, the multilayer packaging material, preferentially web of packaging material 3, may comprise at least a layer of fibrous material, such as e.g. a paper or cardboard layer, and at least two layers of heat-seal plastic material, e.g. polyethylene, interposing the layer of fibrous material in between one another. One of these two layers of heat-seal plastic material may define the respective inner face of finalized packages 2 eventually contacting the pourable product.

According to some possible non-limiting embodiments, the multilayer packaging material, preferentially web of packaging material 3, may also comprise a layer of gas- and light-barrier material, e.g. aluminum foil or ethylene vinyl alcohol (EVOH) film, preferentially being arranged between one of the layers of the heat-seal plastic material and the layer of fibrous material. Preferentially, the multilayer packaging material, preferentially web of packaging material 3, may also comprise a further layer of heat-seal plastic material being interposed between the layer of gas- and lightbarrier material and the layer of fibrous material.

In more detail, each finalized package 2 may extend along a longitudinal axis, and preferentially may have a longitudinal seam portion (extending along the respective longitudinal axis) and a pair of transversal sealing fins, preferentially a transversal top sealing fin and a transversal bottom sealing fin .

Preferentially, each finali zed package 2 may have a substantially parallelepiped structure .

Furthermore , each finali zed package 2 may comprise at least a first end portion and a second end portion disposed at opposite sides of finali zed package 2 and an intermediate portion interposed between the first end portion and the second end portion . Preferentially, each first end portion may define a bottom of the respective finali zed package 2 and each second end portion may define a top of the respective finali zed package 2 .

In further detail , each first end portion and each second end portion may comprise at least one respective transversal wall (being transversal to the respective longitudinal axis of the respective finali zed package 2 ) .

Preferentially, each intermediate portion may comprise and/or define a side wall , e . g . formed from a plurality of interconnected side wall portions , extending between the respective transversal walls .

More speci fically, the respective transversal wall of each first end portion may define a bottom wall and the respective transversal wall of each second end portion may define a top wall . Preferentially, the bottom wall may have a support surface adapted to be placed on a

(hori zontal ) plane , such as e . g . a shel f within a distribution point, and the top wall may be opposite to the bottom wall.

According to some possible non-limiting embodiments, each finalized package 2 may also comprise an opening device, such as a closure or a lid.

According to some possible non-limiting embodiments, each opening device may be applied to the respective multilayer packaging material, preferentially web of packaging material 3, or onto semi-finalized packs 5 or onto finalized packages 2.

Preferentially, each opening device may be provided on the respective second end portion, preferentially the respective transversal wall defining the respective top wall .

With particular reference to Figures 1 and 2, packaging machine 1 may be configured to produce (sealed) semi-finalized packs 5, such as e.g. pillow packs, being filled with the pourable product and to further treat and/or manipulate and/or form semi-finalized packs 5 for obtaining finalized packages 2.

With particular reference to Figure 2, each semifinalized pack 5 may extend along a respective longitudinal axis A, and preferentially may comprise a longitudinal sealing band 6 (extending along and/or being parallel to longitudinal axis A) .

Each semi-finalized pack 5 may comprise a central main body 8 , one or more flaps 9 protruding away, preferentially laterally protruding away, from the respective central main body 8 and one or more transversal sealing fins 10 , preferentially transversal to longitudinal axis A.

In further detail , each sealing fin 10 may be arranged at a respective end portion 7 of the respective semi- finali zed pack 5 .

Preferentially, each semi- finali zed pack 5 may comprise at least two transversal sealing fins 10 , preferentially transversal to longitudinal axis A, arranged at respective end portions 7 of the respective semi- finali zed pack 5 opposite to one another .

Moreover, each sealing fin 10 may define a respective transversal sealing fin of the respective finali zed package 2 ( obtained from the respective semi- finali zed pack 5 ) .

According to some preferred non-limiting embodiments , each sealing fin 10 may protrude from the respective central main body 8 along a direction parallel to the respective longitudinal axis A.

According to some preferred non-limiting embodiments , each longitudinal sealing band 6 may define a corresponding longitudinal seam portion of the respective finali zed package 2 ( obtained from the respective semi- finali zed pack 5 ) . According to some preferred non-limiting embodiments , each end portion 7 may taper from the respective central main body 8 to and/or into the respective sealing fin 10 .

Preferentially, each flap 9 may carry a portion of a respective sealing fin 10 .

According to some preferred non-limiting embodiments , at least one end portion 7 may comprise two respective flaps 9 laterally extending from opposite lateral sides of the respective central main body 8 . In even further detail , each end portion 7 may comprise at least two respective flaps 9 .

According to some preferred non-limiting embodiments , each semi- finali zed pack 5 may comprise a respective first end portion 11 , a respective second end portion 12 opposite to the respective first end portion 11 and an intermediate portion 13 interposed between first end portion 11 and second end portion 12 .

Preferentially, each first end portion 11 , each second end portion 12 and each intermediate portion 13 form respectively the respective first end portion, the respective second end portion and the respective intermediate portion of the respective finali zed package 2 .

Each first end portion 11 and each second end portion

12 may comprise one respective sealing fin 10 and a respective pair of flaps 9 .

Moreover, each first end portion 11 and each second end portion 12 may comprise one respective end portion 7 .

With particular reference to Figure 1 , packaging machine 1 may comprise at least :

- a forming apparatus 15 configured to form and/or obtain semi- finali zed packs 5 of the pourable product , preferentially from the multilayer packaging material , even more preferentially from the web of packaging material 3 ; and

- a folding apparatus 16 configured to receive the semi- finali zed packs 5 from forming apparatus 15 and to form finali zed packages 2 of the pourable product from semi- finali zed packs 5 .

In more detail , forming apparatus 15 may comprise :

- an isolation chamber 17 configured to separate an inner ( sterile ) environment from an outer (hostile ) environment ;

- a conveying device 18 configured to advance web of packaging material 3 along a web advancement path P at least to a tube forming station at which web of packaging material 3 is formed, in use , into a tube 19 and for advancing tube 19 along a tube advancement path Q;

- a tube forming and sealing device 20 at least partially arranged within isolation chamber 17 and configured to form and longitudinally seal tube 19 at the tube forming station within isolation chamber 17 ; - a filling device 21 for filling tube 19 with the pourable product ; and

- a pack forming unit configured to at least form and transversally seal tube 19 , preferentially to also transversally cut tube 19 , preferentially during advancement of tube 19 along tube advancement path Q, for obtaining and/or producing semi- finali zed packs 5 .

Preferentially, each sealing fin 10 may result from the transversal sealing and cutting of tube 19 .

Preferentially, the pack forming unit may be arranged downstream of isolation chamber 17 and tube forming and sealing device 20 along tube advancement path Q .

Moreover, tube 19 may extend along a longitudinal axis , preferentially having a vertical orientation .

Furthermore , packaging machine 1 may further comprise a sterili zation apparatus for sterili zing at least a portion of web of packaging material 3 at a sterili zation station arranged upstream of the tube forming station along web advancement path P .

In more detail , filling device 21 may comprise at least a filling pipe 22 being in fluid connection or being controllable to be in fluid connection with a pourable product storage tank (not shown and known as such) and being, in use , partially placed within tube 19 for feeding the pourable product into the , in use , advancing tube 19 .

More speci fically, tube forming and sealing device 20 may comprise at least a tube forming assembly 23 configured to form tube 19 from web of packaging material 3 , in particular by overlapping the respective opposite lateral edges of web of packaging material 3 , and at least a sealing head 24 configured to longitudinally seal tube 19 , in particular along the portion of tube 19 obtained by overlapping the opposite lateral edges of web of packaging material 3 .

Even more speci fically, tube forming assembly 23 and sealing head 24 may be arranged within isolation chamber 17 .

According to some preferred non-limiting embodiments , the pack forming unit may comprise :

- a plurality of pairs of at least one operative assembly (not shown and known as such) and at least one respective counter-operative assembly (not shown and known as such) ; and

- a conveying unit (not shown and known as such) configured to advance the operative assemblies and the respective counter-operative assemblies along respective conveying paths .

More speci fically, each operative assembly may be configured to cooperate , in use , with the respective counter-operative assembly of the respective pair for forming, transversally sealing, and preferential ly also transversally cutting, tube 19 for obtaining one respective semi- f inali zed pack 5 , in particular when, in use , advancing along a respective operative portion of the respective conveying path .

With particular reference to Figures 1 and 3a to 6 , folding apparatus 16 may comprise at least a folding unit

30 ( only partially shown to the extent necessary for the comprehension of the present invention) configured to obtain finali zed packages 2 from the respective semifinali zed packs 5 , and preferentially an infeed conveyor

31 configured to advance semi- finali zed packs 5 to folding unit 30 .

In more detail , infeed conveyor 31 may be interposed between folding unit 30 and forming apparatus 15 and may be configured to receive semi- finali zed packs 5 from forming apparatus 15 and to feed semi- finali zed packs 5 to folding unit 30 .

With particular reference to Figures 1 and 3a to 5c, folding apparatus 16 , in particular folding unit 30 , may comprise :

- a plurality of retaining pockets 32 configured to receive one respective semi- finali zed pack 5 at a time ; and

- a conveying device 33 ( only partially shown to the extent necessary for the comprehension of the present invention) configured to advance retaining pockets 32 along an endless path and through a receiving station 34 at which each semi- finali zed pack 5 is fed into one respective retaining pocket 32 , and preferentially a release station at which each finali zed package 2 is released from the respective retaining pocket 32 .

Preferentially, folding apparatus 16 , in particular folding unit 30 , may be configured to manipulate semifinali zed packs 5 so as to form finali zed packages 2 during advancement of retaining pockets 32 along the endless path .

In more detail , in use , each semi- finali zed pack 5 may be folded into the respective finali zed package 2 while being retained within the respective retaining pocket 32 and during advancement of the respective retaining pocket 32 between receiving station 34 and the release station .

With particular reference to Figures 1 and 3 to 4c, each retaining pocket 32 may comprise a retaining space , preferentially delimited by at least two respective retaining plates 35 of the respective retaining pocket 32 .

More speci fically, one retaining plate 35 may be arranged upstream of the other retaining plate 35 along the endless path . In other words , each retaining pocket 32 may comprise a leading retaining plate 35 (with respect to the endless path) and a trailing retaining plate 35 (with respect to the endless path) .

Preferentially but not necessarily, the respective retaining plates 35 of each retaining pocket 32 may be configured to execute a relative movement such to allow for insertion and release of the respective semi- finali zed packs 2 . In addition, the respective retaining plates 35 of each retaining pocket 32 may be configured so as to get into engagement with the respective semi- finali zed pack 5 and the respective finali zed package 2 , e . g . for securing and/or shaping the respective semi- finali zed pack 5 and the respective finali zed package 2 .

According to some possible non-limiting embodiments , one retaining plate 35 of each retaining pocket 32 , e . g . the trailing retaining plate 35 , may be fixed (nonmoveable ) with respect to the conveying device 33 and the other retaining plate 35 of each retaining pocket 32 , e . g . the trailing retaining plate 35 , may be moveable with respect to the conveying device 33 so as to control the relative movement between the respective retaining plates 35 of each retaining pocket 32 .

With particular reference to Figures 1 and 4a to 4c, conveying device 33 may be configured to advance retaining pockets 32 through receiving station 34 at which one semifinali zed pack 5 at a time is fed into a respective retaining pocket 32 . Preferentially, conveying device 33 may also be configured to advance retaining pockets 32 through the release station at which finali zed packages 2 formed form semi- finali zed packs 5 during advancement within retaining pockets 32 are released out of retaining pockets 32 .

As will be explained in further detail further below, conveying device 33 may also be configured to advance retaining pockets 32 through one or more treatment stations , the treatment stations being interposed between receiving station 34 and the release station .

According to some possible non-limiting embodiments , conveying device 33 may be configured to intermittently advance retaining pockets 32 along the endless path .

In more detail , conveying device 33 may comprise a conveyor wheel 38 , which is rotatable around a respective rotation axis B .

Additionally, conveying device 33 may comprise an actuation unit configured to actuate rotation, preferentially in an intermittent manner, of conveyor wheel 38 for advancing retaining pockets 32 along the endless path .

According to some possible non-limiting embodiments , each retaining pocket 32 may be carried by conveyor wheel 38 . Preferentially, retaining pockets 32 may be angularly spaced apart from one another about rotation axis B .

In more detail , each retaining plate 35 may radially protrude from conveyor wheel 38 .

According to some possible non-limiting embodiments , one retaining plate 35 of each retaining pocket 32 may be integral to conveyor wheel 38 and the other retaining plate 35 may be moveable with respect to conveyor wheel 38 .

More speci fically, each trailing retaining plate 35 may be integral to conveyor wheel 38 and/or each leading retaining plate 35 may be moveable with respect to conveyor wheel 38 . With particular reference to Figure 1 , each semifinali zed pack 5 may be fed to receiving station 34 by infeed conveyor 31 . At receiving station 34 each semifinali zed pack 5 is trans ferred from infeed conveyor 31 to the respective retaining pocket 32 .

With particular reference to Figures 1 and 3 to 4c, each retaining pocket 32 may comprise a first terminal portion 37 and a second terminal portion 36 opposite to first terminal portion 37 . Preferentially, each second terminal portion 36 may be adj acent and/or connected to conveyor wheel 38 .

Moreover, each retaining pocket 32 may comprise an open end arranged at the respective first terminal portion 37 .

According to some possible non-limiting embodiments , each semi- finali zed pack 5 may be arranged within the respective retaining pocket 32 such that the respective second end portion 12 is placed adj acent to the respective second terminal portion 36 and the respective first end portion 11 is arranged adj acent to the respective first terminal portion 37 .

Moreover, each semi- finali zed pack 5 may be fed into the respective retaining pocket 32 with the respective sealing fins 10 being in a respective unfolded position and the respective flaps 9 being in a non- folded position, meaning that the sealing fins 10 protrude , preferentially along a direction parallel to the respective longitudinal axis A, and the respective flaps 9 protrude , preferentially laterally protrude , from the respective central main body 8 .

Operation of folding apparatus 16 , in particular folding unit 30 , foresees to fold each sealing fin 10 from the respective unfolded position to a respective folded position in which each sealing fin 10 is folded onto and/or towards the respective central main body 8 , preferentially the respective second end portion 12 , and to fold each f lap 9 from the respective non- folded position to a respective bent position in which each flap

9 is folded onto and/or towards the respective central main body 8 , preferentially the respective intermediate portion 13 .

With particular reference to Figures 1 and 3 to 5c, each retaining pocket 32 may comprise a respective folding device 45 configured to fold one respective sealing fin

10 from the respective unfolded position to the respective folded position and to fold the respective flap ( s ) 9 from the respective non- folded position to the respective bent position . Preferentially, each folding device 45 may be configured to fold the respective sealing fin 10 and the respective flap ( s ) 9 being placed at the respective second terminal portion 36 .

Moreover, each folding device 45 may be configured to fold the respective sealing fin 10 and the respective flap ( s ) 9 protruding from the respective second end portion 12 .

According to some preferred non-limiting embodiments, each folding device 45 may be arranged at and/or may define the respective second terminal portion 36.

In particular, each semi-finalized pack 5 is inserted, in use, into the respective retaining pocket 32 such that each folding device 45 may be configured to fold the respective sealing fin 10 and the respective flap(s) 9 which are placed within the respective retaining pocket 32 prior to the other sealing fin 10 and the other flaps 9. Thus, for the following description we rely on the term leading sealing fin 10 and leading flaps 9 for respectively the respective sealing fin 10 and the respective flap(s) 9 entering at first the respective retaining pocket 32 and the term trailing sealing fin 10 and trailing flap(s) 9 for respectively the respective sealing fin 10 and the respective flap(s) 9 following the leading sealing fin 10 and the leading flap(s) 9 (i.e. the trailing sealing fin 10 is the fin opposite to the leading sealing fin 10 and the trailing flap(s) 9 is/are the flap(s) opposite to the leading flap(s) 9) . Thus, each leading sealing fin 10 and each leading flap 9 is positioned adjacent to the respective second terminal portion 36 and each trailing sealing fin 10 and each trailing flap 9 is positioned adjacent to the respective first terminal portion 37.

In more detail, each folding device 45 may be configured to fold each leading sealing fin 10 and the respective leading flap(s) 9. As will be shown further below, according to the present non-limiting embodiment , trailing sealing fins 10 may be folded through an alternative mechanism and not by means of folding devices 45 . In particular, the alternative mechanism is not associated to each single retaining pocket 32 but may be at a fixed station .

Advantageously and with particular reference to Figures 3a to 5c, each folding device 45 may comprise a folding element 46 moveable between a rest position ( see Figures 4a and 5a ) and an active position ( see Figures 4c and 5c ) for moving the respective leading sealing fin 10 from the unfolded position to the folded position and to move the respective leading flap ( s ) 9 from the non- folded position to the bent position .

Preferentially, each folding element 46 when being in the rest position allows insertion of the respective semi- finali zed packs 5 into the respective retaining pocket 32 without interacting with the respective leading sealing fins 10 and the respective leading flaps 9 .

Preferentially, each folding device 45 may comprise a free space 47 for receiving the respective leading sealing fin 10 , preferentially the respective leading sealing fin 10 , in the unfolded position at receiving station 34 . Preferentially, with the respective folding element 46 being in the respective rest position, the respective folding element 46 is impeded from interacting with the respective leading sealing fin 10 during placement of the respective semi- finali zed pack 5 within the respective retaining pocket 32 . Even more preferentially, each folding element 46 may be configured to move through the respective free space 47 while moving, in use , from the respective rest position to the respective active position .

More speci fically, in use , each folding element 46 may be designed to be positioned in the respective rest position with the respective retaining pocket 32 being at the receiving station 34 such that during insertion of the respective semi- finali zed packs 5 , the respective leading sealing fin 10 can enter free space 47 without being moved from the unfolded position and/or without impacting with any portions of the respective retaining pocket 32 . This guarantees that during insertion of each semi- finali zed pack 5 into the respective receiving pocket 32 , the respective leading sealing fin 10 entering into the respective retaining space is not subj ect to any undesired mechanical impacts . Furthermore , this allows a gentle treatment of semi- finali zed packs 5 .

Advantageously, folding apparatus 16 , in particular folding unit 30 , may further comprise an actuation unit 48 configured to set each folding element 46 in the respective rest position at receiving station 34 and to move each folding element 46 from the respective rest position to the respective active position during advancement of the respective retaining pocket 32 from receiving station 34 and along the endless path, and preferentially to the release station . Thus , only once each semi- finali zed pack 5 is arranged within the respective retaining pocket 32 , folding of the respective leading sealing fin 10 and the respective leading flap ( s ) 9 may start . Hence , it is possible to precisely control the overall folding process without unnecessarily stressing semi- finali zed pack 5 .

In more detail and with particular reference to Figures 1 and 3 to 5c, each folding element 46 may comprise at least a first interaction surface 49 configured to engage the respective leading sealing fin 10 and one or more second interaction surfaces 50 , preferentially at least two , more preferentially exactly two , configured to engage the respective leading flap ( s ) 9 so as to fold respectively the respective leading sealing fin 10 into the folded position and the respective leading f lap ( s ) 9 into the respective bent positions during movement of the folding element 46 from the respective rest position to the active position .

Preferentially, one second interaction surface 50 of each folding element 46 may be configured to interact with one of the respective leading flaps 9 of the respective semi- finali zed packs 5 and the other second interaction surface 50 of each folding element 46 may be configured to interact with the other respective leading flap 9 .

According to some preferred non-limiting embodiments , at least a portion of each first interaction surface 49 may be interposed between the two respective second interaction surfaces 50 . Preferentially, each first interaction surface 49 and/or each second interaction surface 50 may have a curved portion .

Preferentially, the respective second interaction surfaces 50 of each folding element 46 may be spaced apart from one another along a main axis C of the respective folding element 46 .

Preferentially, at least portions of the respective two second interaction surfaces 50 of each folding element 46 may face one another .

According to some preferred non-limiting embodiments , each folding element 46 may comprise a main bar 51 and two lateral protrusions 52 protruding from main bar 51 .

Preferentially, each main bar 51 may extend along the respective main axis C and the respective lateral protrusions 52 may be spaced apart from one another along the respective main axis C .

More preferentially, each lateral protrusion 52 may extend from a respective end portion 53 of the respective main bar 51 .

Preferentially, each main bar 51 and the respective lateral protrusions 52 may be provided as a single piece .

Preferentially, each lateral protrusion 52 may have one respective second interaction surface 50 of the respective folding element 46 and each main bar 51 may comprise the respective first interaction surface 49 .

With particular reference to Figures 3a to 4c, each folding element 46 may be configured such that during movement of folding element 46 from the respective rest position to the respective active position at first folding element 46 , preferentially due to the interaction of the respective first interaction surface 49 with the respective leading sealing fin 10 , starts to move the respective leading sealing fin 10 from the respective unfolded position towards the respective folded position . After having at least partially folded the respective leading sealing fin 10 , the folding element 46 , preferentially due to the interaction of the respective second interaction surfaces 50 with the respective leading flaps 9 , begins to move the respective leading f laps 9 from the respective non- folded position to the respective bent position . In this way, it is possible to guarantee a correct folding of the respective leading sealing fins 10 and of the respective leading flaps 9 of each semifinali zed pack 5 .

According to some preferred non-limiting embodiments , each folding element 46 may be configured such that during movement of folding element 46 from the respective rest position to the respective active position, folding element 46 , preferentially by means of the respective first interaction surface 49 engaging the respective leading sealing fin 10 , folds the respective leading sealing fin 10 in an advancement direction of retaining pockets 32 , i . e . a direction of advancement of the respective retaining pocket 32 along the endless path . Moreover, during movement of each folding element 46 from the respective rest position to the respective active position, the respective first interaction surface 49 may move in the advancement direction . This is of particular advantage when each semi- finali zed pack 5 is provided with a respective opening device . In this way, in fact , leading sealing fin 10 is folded over sealing band 6 so as to obtain a large area free from sealed portions in the top wall of finali zed package 2 , which may therefore receive a correspondingly large opening device .

Preferentially, after placement of each semifinali zed pack 5 into the respective retaining pocket 32 the respective folding element 46 , preferentially the respective first interaction surface 49 , may be arranged behind ( downstream of ) the respective leading sealing 10 long the endless path .

According to some preferred non-limiting embodiments , each retaining pocket 32 may comprises a seat 59 for the respective folding element 46 . In particular, each folding element 46 may be moveably arranged within the respective seat 59 .

With particular reference to Figures 3a, 3b and 5a to 5c, each retaining pocket 32 may also comprise an abutment surface 61 , preferentially arranged at and/or partially defining the respective second terminal portion 36 , designed to receive and/or carry an engagement portion of the respective central main body 8 , preferentially of the respective second end portion 12 , of the respective semi- finali zed pack 5 .

Preferentially, in use , the respective semifinali zed pack 5 may be introduced into the respective receiving pocket 32 until the respective engagement portion abuts against the respective abutment surface 61 .

Preferentially, the respective leading sealing f in 10 may protrude from the respective engagement portion into the respective free space 47 with the engagement portion being engaged with ( resting on) the respective abutment surface 61 , and the respective folding element 46 being in the respective rest position .

Advantageously, actuation unit 48 may be configured to control each folding element 46 from the respective rest position to the respective active position with the respective engagement portion abutting, in use , against the respective abutment surface 61 , and preferentially the respective leading sealing fin 10 protruding into the free space 47 . In other words , in use , only after the respective engagement portion abuts against the respective abutment surface 61 , actuation unit 48 moves the respective folding element 46 from the respective rest position to the respective active position . In this way, it is possible to guarantee a gentle treatment of semifinali zed packs 5 .

With particular reference to Figures 5a to 5c, each retaining pocket 32 may comprise a support structure 62 , preferentially arranged at the respective second terminal portion 36 . Preferentially, each support structure 62 may comprise the respective abutment surface 61 .

According to some possible non-limiting embodiments , each support structure 62 may comprise and/or define and or/delimit the respective seat 59 .

More speci fically, each support structure 62 may comprise a pair of grooves at least partially de fining the respective seat 59 . Moreover, a portion of each folding element 46 , preferentially of the respective main bar 51 , may move within the respective grooves when moving between the respective rest position and the respective active position .

According to some preferred non-limiting embodiments , each support structure 62 may be f ixed to one respective retaining plate 35 , preferentially the respective trailing retaining plate 35 and/or the fixed retaining plate 35 .

With particular reference to Figures 4a to 5c, actuation unit 48 may be configured to angularly move each folding element 46 for controlling the respective folding element 46 from the respective rest position to the respective active position .

Preferentially, during movement of each folding element 46 from the respective rest position to the respective active position, the folding element 46 moves in the advancement direction, i . e . the direction of advancement of retaining pockets 32 along the endless path . According to some preferred non-limiting embodiments and with particular reference to Figures 3b and 6 , actuation unit 48 may comprise a cam mechanism 64 moving the folding elements 46 between the respective rest positions and the respective active positions .

Preferentially, cam mechanism 64 may comprise a cam profile 65 ( see Figure 6 ) and a plurality of cam followers 66 ( see Figure 3b ) , each cam follower 66 being coupled to one respective folding element 46 .

Moreover, actuation unit 48 may further comprise a plurality of coupling structures 67 , each one carrying one respective cam follower 66 and being connected to one respective folding element 46 .

Preferentially, each folding element 46 may be hinged to the respective coupling structure 67 and may be angularly moveable about a rotation axis E .

In more detail , each coupling structure 67 may comprise a first portion 68 hinged to conveying device 33 , preferential ly conveying wheel 38 , and a second portion 69 hinged to the respective first portion 68 . Moreover, each folding element 46 may be hinged to the respective second portion 69 .

Preferentially, conveying device 33 , preferentially conveyor wheel 38 , may be also configured to move each coupling structure 67 along the endless path .

In particular, advancement of coupling structures 67 is ( substantially) simultaneous with respect to the respective retaining pockets 32 . More in particular, cam mechanism 64 may be configured such that each coupling structure 67 is subj ect to movements with respect to the respective retaining pockets 32 during advancement along the endless path and such to control the respective folding element 46 between the respective rest position and the respective active position .

Moreover, during advancement of each coupling structure 67 each first portion 68 , the respective second portion 69 and the respective folding element 46 are subj ect to respective angular movements .

In use , interaction between cam followers 66 and cam profile 65 may determine the speci fic movement of the respective folding element 46 .

In more detail , in use , cam followers 66 may be arranged one after the other along the endless path and cyclically move along cam profile 65 , preferentially such that the respective folding elements 46 cyclically move between the respective rest position and the respective active position .

In further detail , in use , the angular position of cam followers 66 with respect to rotation axis B may determine the pos ition and/or movement of folding elements 46 .

With particular reference to Figure 6 , folding apparatus 16 , pre ferentially folding unit 30 , may comprise a plate 70 carrying cam profile 65 .

Preferentially, plate 70 may be mounted to conveying device 33 in a fixed position with respect to conveying wheel 38 .

Moreover, plate 70 may also carry a further cam profile 71 configured to determine the relative motion of the respective retaining plates 35 of each retaining pocket 32 .

Preferentially, folding apparatus 16 , preferentially folding unit 30 , may comprise further cam followers 72 each coupled to one respective retaining plate 35 of a respective retaining pocket 32 , e . g . the respective leading retaining plate 35 , and configured to run along further cam prof ile 71 so as to determine the relative motion .

With particular reference to Figures 5a to 5c, each retaining pocket 32 may also comprise a housing seat 75 configured to receive an opening device of the respective semi- finali zed pack 5 . Each housing seat 75 may for example be provided in the form of an aperture provided in the respective support structure 54 and the respective folding element 50 .

Preferentially, each folding element 46 may comprise a cut-out 76 configured such that folding element 46 avoids contact with the respective opening devices during movement of the folding element 46 from the rest position to the active position .

According to some preferred non-limiting embodiments , folding apparatus 16 , in particular folding unit 30 , may further comprise a sealing device , preferentially having a heating unit , configured to heat seal leading flaps 9 onto the respective central main bodies 8 , preferentially the respective intermediate portions 13 . In particular, heating unit may be configured to heat leading flaps 9 .

Additionally, folding apparatus 16 , in particular folding unit 30 , even more particular the sealing device , may further comprise a pressuring device configured to exert a force onto leading flaps 9 so as to promote sealing of leading flaps 9 onto the respective central main bodies 8 , preferentially the respective intermediate portions 13 .

In an embodiment not-shown, additionally or alternatively, each folding device 45 , preferentially the respective folding elements 46 , may be configured to exert a force onto leading flaps 9 so as to promote sealing of leading flaps 9 .

With particular reference to Figure 1 , folding apparatus 16 , in particular folding unit 30 , may also comprise a folding group 77 configured to fold each trailing sealing fin 10 and each trailing flap 9 independently from folding of the respective leading sealing fin 10 and of the respective leading flap ( s ) 9 .

In particular, folding group 77 may be configured to fold each trailing flap 9 onto the respective first end portion 11 , in particular onto the part of the semifinished pack 5 that will become the bottom wall of the respective finali zed package 2 .

Preferentially, folding group 77 may be fixed with respect to retaining pockets 32, i.e. folding group 75 does not move and interacts with each semi-finalized pack 5 when being arranged and remaining in a fixed position.

Moreover, folding apparatus 16, in particular folding unit 30, may also comprise an auxiliary sealing device for sealing each trailing flap 9 onto the respective central main body 8, preferentially the respective first end portion 11.

In use, packaging machine 1 forms finalized packages 2 filled with the pourable product.

In particular, the method for forming packages 2 comprises the main steps of:

- forming semi-finalized packs 5 by operation of forming apparatus 15; and folding semi-finalized packs 5 into finalized packages 2 by operation of folding apparatus 16.

In more detail, the main step of forming packs 5, comprises at least the steps of: advancing web of packaging material 3 along advancement path P, in particular by operation of conveying device 18;

- folding web of packaging material 3 into tube 19, in particular within isolation chamber 17, by operation of tube forming and sealing device 20, in particular tube forming assembly 23; longitudinally sealing tube 19, in particular within isolation chamber 17, by operation of tube forming and sealing device 20, in particular sealing head 24; filling tube 19 with the pourable product by operation of filling device 21, in particular filing pipe 22;

- advancing tube 19 along tube advancement path Q by operation of conveying device 18 and/or the pack forming unit; and

- obtaining semi-finalized packs 5 from tube 19 by forming, transversally sealing and transversally cutting tube 19 by operation of the pack forming unit and during advancement of tube 19 along tube advancement path Q.

Moreover, the step of forming may also comprise the step of sterilizing web of packaging material 3 at the sterilization station.

In more detail, the step of folding semi-finalized packs 5 comprises the sub-steps of:

- feeding semi-finalized packs 5 to folding unit 30 by operation of infeed conveyor 31; and

- final folding semi-finalized packs 5 by operation of folding unit 30.

More specifically, during the sub-step of feeding, semi-finalized packs 5 may be fed into respective retaining pockets 32 at receiving station 34.

Preferentially, while being fed into retaining pockets 32, the respective leading sealing fins 10 may be placed within the respective free space 47, and preferentially at the same time the respective engagement portion of the respective semi-finalized pack 5 may abut against the respective abutment surface 61. Moreover, during the sub-step of final folding, retaining pockets 32 advance , preferentially intermittently advance , along the endless path .

During advancement of retaining pockets 32 the respective folding devices 45 fold the respective leading sealing fins 10 from the respective unfolded position to the respective folded position and fold the respective leading flap ( s ) 9 from the respective non- folded positions to the respective bent positions by moving the respective folding elements 46 from the respective rest pos ition to the respective active position .

Preferentially, control of folding elements 46 from the respective rest position to the respective active position is driven by cam mechanism 64 .

In one embodiment , the leading flaps 9 are heated by the heating unit allowing to seal the leading flaps 9 onto the respective main central body 8 .

Additionally, during the sub-step of final folding, also trailing sealing fins 10 and trailing flaps 9 are folded by folding group 77 .

Moreover, the auxiliary sealing device may seal trailing flaps 9 onto the respective central main body 8 , preferentially onto the respective first end portion 11 .

The advantages of folding apparatus 16 , preferentially folding unit 30 , according to the present invention will be clear from the foregoing description . In particular, semi- finali zed packs 5 are gently treated when folding leading sealing fins 10 and leading flaps 9 .

Clearly, changes may be made to folding apparatus 16 and/or packaging machine 1 as described herein without , however, departing from the scope of protection as defined in the accompanying claims .

According to some non-limiting embodiments , each seat 59 may comprise a guiding surface configured to guide movement of the respective folding element 46 when moving between the respective rest position and the respective active position .