EP4667369A1

EP4667369A1 - Packaging machine for forming packages filled with a pourable product

Info

Publication number: EP4667369A1
Application number: EP25181643.5A
Authority: EP
Inventors: Stefano Costa; Luciano AMIDEI
Original assignee: Tetra Laval Holdings and Finance SA
Current assignee: Tetra Laval Holdings and Finance SA
Priority date: 2024-06-17
Filing date: 2025-06-10
Publication date: 2025-12-24
Also published as: WO2025261821A1

Abstract

There is descried a packaging machine (1) comprising a tube forming and sealing device (10) configured to form and longitudinally seal a tube (3) from the, in use, advancing web (4) of packaging material, a filling device, a package forming apparatus (16) configured to form and transversally seal the packages (2) and a pressurization promoting device (30) configured to guarantee a pressurization of the tube (3). The conveying device (5) is configured to advance the tube (3) along a tube advancement path (Q). The packaging machine (1) further comprises a control device (23) configured to interact with the tube (3) and to control an orientation and/or alignment and/or angular position of the tube (3). The control device (23) comprises a pair of interaction rollers (24) configured to engage, in use, the tube (3) at a contact station (25) arranged downstream of the pressurization promoting device (30). The control device (23) also comprises a movement unit (31) configured to modify relative positions of the interaction rollers (24) with respect to one another and with respect to an advancement direction (D) of the tube (3).

Description

TECHNICAL FIELD

The present invention relates to a packaging machine for forming packages filled with a pourable product, preferentially a pourable food product.

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 liquid or pourable food products known as Tetra Brik Aseptic (registered trademark), which is made by sealing and folding laminated strip packaging material. The packaging material has a multilayer structure comprising a base layer, e.g. of paper, covered on both sides with layers of heat-seal plastic material, e.g. polyethylene. In the case of aseptic packages for long-storage products, such as UHT milk, the packaging material also comprises a layer of oxygen-barrier material (an oxygen-barrier layer), 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, which advance a web of packaging material through a sterilization apparatus for sterilizing the web of packaging material at a sterilization station and to an isolation chamber (a closed and sterile environment) in which the sterilized web of packaging material is maintained and advanced. During advancement of the web of packaging material through the isolation chamber, the web of packaging material is folded and sealed longitudinally at a tube forming station to form a tube having a longitudinal seam portion, the tube being further fed along a vertical advancing direction.
For completing 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 package forming apparatus of the packaging machine during advancement along the vertical advancing direction. Pillow packages are so obtained, each pillow package having a longitudinal sealing band, a top transversal sealing band and a bottom transversal sealing band.
A typical packaging machine comprises a conveying device for advancing the web of packaging material along a web advancement path and the tube formed from the web of packaging material along a tube advancement path, the sterilization apparatus for sterilizing the web of packaging material prior to its formation into the tube, a tube forming and sealing device at least partially arranged within the isolation chamber and being configured to form the tube from the advancing web of packaging material and to longitudinally seal the tube, a filling device for filling the tube with the pourable product and the package forming apparatus adapted to form, transversally seal and cut individual packages from the tube of packaging material.
The package forming apparatus comprises a sealing device and a counter-sealing device that cooperate with one another to flat-lay and transversally seal the tube. During operation of the packaging machine it is necessary to guarantee a desired positioning of the tube, in particular such that the longitudinal seam portion, which defines a local thickening of a portion of the tube, is arranged in a correct manner (i.e. in a defined position) with respect to the sealing device and the counter-sealing device. In fact, at least one of the sealing device and the counter sealing device, in particular the counter sealing device, comprises a cavity designed to accommodate the local thickening during transversal sealing of the tube.
Even though the known packaging machine work satisfyingly well a need is felt in the sector to further improve the known packaging machines.

DISCLOSURE OF INVENTION

It is therefore an object of the present invention to provide an improved packaging machine for forming packages filled with a pourable product, preferentially a pourable food product.
According to the present invention, there is provided a packaging machine as claimed in claim 1.
Preferred non-limiting embodiments of the packaging machine are claimed in the claims being directly and indirectly dependent on claim 1.

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 according to the present invention, with parts removed for clarity;
Figure 2 is a schematic view of a detail of the packaging machine of Figure 1, with parts removed for clarity;
Figure 3 is a front view of a detail of the packaging machine of Figure 1, with parts removed for clarity;
Figures 4A to 4C are perspective views of a portion of the packaging machine in three different configurations, with parts removed for clarity;
Figure 5 is another perspective view of the portion of Figures 4A to 4C, with parts removed for clarity;
Figure 6 is a back view of the portion of Figures 4A to 4C, with parts removed for clarity;
Figure 7 is a further perspective view of the portion of Figures 4A to 4C, with parts removed for clarity; and
Figure 8 is a perspective view of a variant of the portion of Figures 4A to 4C, with parts removed for clarity.

BEST MODES FOR CARRYING OUT THE INVENTION

Number 1 indicates as a whole a packaging machine for producing packages 2, preferentially sealed packages 2, of a pourable food product, in particular a pourable food product, such as milk, milk drinks, yoghurt, yoghurt drinks, fruit juice, wine, tomato sauce, emulsions, beverages containing pulp, salt, sugar, etc.
Packaging machine 1 may be configured to form packages 2 from a tube 3 folded from a web 4 of packaging material. Preferentially, in use, tube 3 extends along a longitudinal axis A, more preferentially having a vertical orientation.
Web 4 of packaging material may have a multilayer structure, preferentially having heat-seal properties (i.e. portions of the multilayer packaging material can be sealed to one another).
In further detail, the multilayer packaging material may comprise at least one layer of fibrous material, such as e.g. paper or cardboard, and at least two layers of heat-seal plastic material, e.g. polyethylene, interposing the layer of fibrous material in between one another. Preferentially, one of the at least two layers of heat-seal plastic material may define the inner face of packages 2 contacting the pourable product.
Moreover, the multilayer packaging material 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 heat-seal plastic material and the layer of fibrous material.
Preferentially, the packaging material may also comprise a further layer of heat-seal plastic material being interposed between the layer of gas- and light-barrier material and the layer of fibrous material.
With particular reference to Figure 1, packaging machine 1 may comprise a conveying device 5 configured to advance (in a known manner) web 4 along a web advancement path P, preferentially from a delivery station to a tube forming station 6, at which, in use, web 4 is formed into tube 3. Conveying device 5 may also be configured to advance tube 3 along a tube advancement path Q.
Packaging machine 1 may comprise an isolation chamber 7 having an inner environment 8, in particular an inner sterile environment, preferentially containing a sterile gas, more preferentially sterile air, and being separated from an outer environment 9.
Packaging machine 1 may comprise a tube forming and sealing device 10 configured to form tube 3, preferentially to fold tube 3 from web 4, and to longitudinally seal tube 3.
Preferentially, tube forming and sealing device 10 may be arranged within isolation chamber 7, more preferentially inner environment 8, and may be configured to form and longitudinally seal tube 3 within isolation chamber 7, more preferentially inner environment 8.
In particular, tube 3 comprises a longitudinal seam portion 22 (resulting from folding and sealing web of packaging material 4 when forming tube 3).
Preferentially, tube forming and sealing device 10 may be configured to gradually fold web 4 into tube 3, preferentially by overlapping a first lateral edge of web 4 and a second lateral edge of web 4, opposite to the first lateral edge of web 4, with one another for forming longitudinal seam portion 22. Preferentially, tube forming and sealing device 10 may be configured to longitudinally seal longitudinal seam portion 22.
Preferentially, conveying device 5 may be configured to advance tube 3 and any intermediate of tube 3 along tube advancement path Q. In particular, with the wording intermediates of tube 3 any configuration of web 4 is meant prior to obtaining the tube structure and after folding of web 4 by tube forming and sealing device 10 has started. In other words, the intermediates of tube 3 are a result of the gradual folding of web 4 so as to obtain tube 3, preferentially by overlapping with one another the first lateral edge of web 4 and the second lateral edge of web 4.
Preferentially, tube forming and sealing device 10 may comprise a plurality of forming ring assemblies 11, preferentially arranged within inner environment 8, configured to gradually fold in cooperation with one another web 4 into tube 3.
Preferentially, tube forming and sealing device 10 may comprise a sealing head 12 configured to longitudinally seal tube 3, preferentially longitudinal seam portion 22.
Preferentially, tube forming and sealing device 10 may also comprise a pressuring assembly configured to exert a mechanical force on tube 3, preferentially on longitudinal seam portion 22. The pressuring assembly may comprise an interaction roller and a counter-interaction roller adapted to exert a mechanical force onto longitudinal seam portion 22 from opposite sides thereof.
Additionally, packaging machine 1 may comprise a filling device 13 for filling, preferentially continuously filling, tube 3 with the pourable product.
With particular reference to Figures 1 and 2, filling device 13 may comprise a filling pipe 14 being and/or being configured to be put in fluid connection with a pourable product storage tank, which is adapted to store/provide for the pourable product to be packaged.
Preferentially, filling pipe 14 may be configured to direct, in use, the pourable product into tube 3. Preferentially, filling pipe 14 may be configured to be, in use, at least partially placed within tube 3 for feeding the pourable product into tube 3. Preferentially, filling pipe 14 may include a linear main pipe portion 15 extending within tube 3, more preferentially main pipe portion 15 may extend (substantially) parallel to tube advancement path Q and/or tube 3.
More preferentially, main pipe portion 15 may comprise a lower section having an outlet opening from which, in use, the pourable product is fed, in use, into tube 3.
Packaging machine 1 may also comprise a package forming apparatus 16 configured to manipulate, preferentially to at least partially shape and/or transversally seal and/or transversally cut, tube 3 for obtaining packages 2 from tube 3.
In more detail, package forming apparatus 16 may be arranged downstream of isolation chamber 7 along tube advancement path Q.
With reference to Figure 2, package forming apparatus 16 may comprise a plurality of operative assemblies 17 (only one shown) and a plurality of counter-operative assemblies 18 (only one shown) configured to manipulate tube 3 for forming packages 2.
More specifically, each operative assemblies 17 may be configured to cooperate with one respective counter-operative assembly 18 for manipulating preferentially to at least partially shape and/or transversally seal and/or transversally cut, tube 3 for forming packages 2.
Additionally, package forming apparatus 16 may comprise a conveying unit configured to advance operative assemblies 17 and counter-operative assemblies 18 along respective advancement paths.
Preferentially, in use, each operative assembly 17 and each counter-operative assembly 18 cyclically advances along the respective advancement path.
Furthermore, each operative assembly 17 and each counter-operative assembly 18 may comprise:

a half-shell 19 configured to contact tube 3 and to at least partially define the shape of packages 2; and/or
one of a sealing element 20 or a counter-sealing element 21 configured to transversally seal tube 3 between adjacent packages 2; and/or
one of a cutting element or a counter-cutting element configured to transversally cut tube 3 between adjacent packages 2.

In particular, each sealing element 20 and the respective counter-sealing element 21 are configured to interpose and squeeze tube 3 for transversally sealing tube 3.
More in particular, each sealing element 20 and the respective counter-sealing element 21 are configured to flat-lay tube 3 along respective transversal cross-sections of tube 3.
Preferentially, one of each sealing element 20 and the respective counter-sealing element 21 comprises a receiving seat for receiving a portion of longitudinal seam portion 22. Most preferentially, each counter-sealing element 21 comprises the respective receiving seat.
Each sealing element 20 may comprise sealing means. Hence, sealing elements 20 have an active role. For example, sealing elements 20 may comprise an ultrasound head for generating ultrasounds for transversally sealing tube 3 by ultrasonic sealing or sealing elements 20 may comprise an induction coil for generating electromagnetic fields for transversally sealing tube 3 by induction sealing.
Moreover, counter-sealing elements 21 may have a passive role.
Advantageously, packaging machine 1 further comprises a control device 23 configured to interact with tube 3 and to control an orientation and/or alignment and/or angular position (with respect to longitudinal axis A) of tube 3, in particular so as to obtain a desired orientation and/or alignment and/or angular position of longitudinal seam portion 22, even more particular with respect to the respective receiving seats.
In other words, control device 23 is configured to control the orientation and/or alignment and/or angular position of tube 3 for orienting and/or aligning and/or angularly positioning longitudinal seam portion 22, in particular with respect to the receiving seats so that the respective portion of longitudinal seam portion 22 is aligned with and enters into the respective receiving seat when tube 3 is interposed between and squeezed by sealing element 20 and the respective counter-sealing element 21.
With particular reference to Figures 3 to 7, control device 23 comprises a pair of interaction rollers 24 configured to engage tube 3 from opposite sides thereof at a contact station 25.
In particular and as will be explained in more detail further below, contact station 25 is chosen such that interaction rollers 24 engage tube 3 at a section being under pressure, i.e. at contact station 25 an internal pressure inside tube 3 is greater than an external pressure outside tube 3. In particular, the internal pressure can be obtained by a pressurized (sterile) gas or the pourable product.
Additionally, interaction rollers 24 interact with tube 3 by means of friction and therefore, by modifying a relative position of interaction rollers 24 with respect to each other and with respect to an advancement direction D of tube 3 it is possible to orient and/or align and/or angularly position tube 3.
In particular, control device 23 comprises only two interaction rollers 24 interposing, in use, tube 3 between one another at contact station 25. By having only two interaction rollers 24 one obtains a control device 23 having a simple design and the possibility to have an easy control.
Advantageously, contact station 25 is arranged downstream (and outside) of inner environment 8.
Advantageously, contact station 25 is arranged upstream of package forming apparatus 16. In particular, contact station 25 is arranged such that operative assemblies 17 and counter-operative assemblies 18 start to contact tube 3 downstream of contact station 25.
Packaging machine 1 comprises a pressurization promoting device 30, in particular arranged, in use, within tube 3, configured to promote a pressurization of tube 3 at contact station 25. As will be explained in more detail below, pressurization promoting device 30 may differ in dependence on whether tube 3 is pressurized by a (sterile) gas or by means of the pourable product.
Advantageously, contact station 25 is arranged downstream of pressurization promoting device 30 along tube advancement path Q. In this way, it is guaranteed that tube 3 is pressurized and interaction rollers 24 can engage tube 3 and control the orientation and/or alignment and/or angular position of tube 3.
Additionally, each interaction roller 24 is rotatable around a respective rotation axis B. In the embodiment shown, each interaction roller 24 is idle, i.e. rotation of each interaction roller 24 around the respective rotation axis B is driven by interaction with tube 3 and not by a dedicated actuation device.
Control device 23 also comprises a movement unit 31 configured to modify the relative positions of interaction rollers 24 with respect to one another and with respect to advancement direction D of tube 3 so as to modify the relative positions of the respective rotation axes B with respect to one another and with respect to advancement direction D of tube 3.
Advantageously, movement unit 31 is configured to move, in particular to simultaneously move, interaction rollers 24 to modify the relative positions of interaction rollers 24 with respect to one another and with respect to advancement direction D of tube 3.
In more detail, movement unit 31 is configured to move one of the interaction rollers 24 along a first path having a first direction component (substantially) parallel to longitudinal axis A and the other interaction roller 24 along a second path having a second direction component (substantially) parallel to longitudinal axis A and opposite to the first direction component.
In even further detail (see e.g. Figure 4A), movement unit 31 is designed so as to be able to arrange interaction rollers 24 in such a way that rotation axes B of interaction rollers 24 are parallel to one another, and in particular also in such a way that rotation axes B of interaction roller 24 are perpendicular to longitudinal axis A.
Advantageously, movement unit 31 is configured to move the interaction rollers 24 between a first extreme position and a second extreme position in which the respective rotation axes B are not parallel to one another.
In particular, when interaction rollers 24 are in the first extreme position (see Figure 4B), the respective rotation axis B of one interaction roller 24 extends along a first roller direction and the respective rotation axis B of the other interaction roller 24 extends along a second roller direction. When interaction rollers 24 are in the second extreme position (see Figure 4C), the respective rotation axis B of the above-mentioned one interaction roller 24 extends along a third roller direction and the respective rotation axis B of the above-mentioned other interaction roller 24 extends along a fourth roller direction. In the embodiment shown, the first roller direction, the second roller direction, the third roller direction and the fourth roller direction differ from each other.
Advantageously, movement between the first extreme position and the second extreme position is through an intermediate position (see Figure 4A) in which the respective rotation axes B of interaction rollers 24 are parallel to one another.
With reference to Figures 4A to 7, movement unit 31 comprises a coupling group 32 movably carrying interaction rollers 24 and an actuator group 33 operatively connected to coupling group 32 and configured to actuate a movement of interaction rollers 24.
In further detail, coupling group 32 comprises a fixed frame 70 and a coupling bar 34 coupled to fixed frame 70 and movably carrying interaction rollers 24.
More specifically, interaction rollers 24 are movably placed within respective housing seats 35 of coupling bar 34. In particular, housing seats 35 are arranged at opposite end portions of coupling bar 34.
Even more specifically, each interaction roller 24 is carried by a shaft 36 movably housed within one respective housing seat 35.
In particular, each shaft 36 is coaxial with the respective rotation axis B.
Advantageously, actuator group 33 is configured to actuate a rotation of coupling bar 34 with respect to fixed frame 70 around a respective bar rotation axis C.
In particular, actuator group 33 may induce an angular movement of coupling bar 34 with respect to fixed frame 70 around bar rotation axis C between a first limit position (see Figure 4B) and a second limit position (see Figure 4C).
In more detail, actuator group 33 may e.g. comprise an electrical motor, a pneumatic actuator or similar.
In further detail, actuator group 33 may comprise an axle connected to coupling group 32, in particular to coupling bar 34.
Additionally according to the variant of Figures 3 to 7, actuator group 33 comprises an abutment element 38 connected to the axle and configured to abut against an engagement surface 39 of coupling group 32 when the axle is at a first angular limit position and a second angular limit position corresponding, respectively, to the first limit position and the second limit position of coupling bar 34.
With particular reference to Figures 4A to 4C and with regard to the variant of Figures 3 to 7, the coupling group 32 also comprises an eccentric 40 operatively connected to coupling bar 34 and to actuator group 33, in particular the axle.
In particular, actuator group 33 is configured to actuate a rotation of coupling bar 34 around bar rotation axis C by angularly moving eccentric 40.
Each shaft 36 comprises a first end 71 rotatably supporting a respective interaction roller 24 and a second end 72, opposite to first end 71, coupled to coupling bar 34 by means of a joint element 73, for example a ball joint. In particular, each second end 72 is coupled to the respective housing seat 35 by means of the respective joint element 73.
Each shaft 36 also comprises an intermediate portion 74 arranged between first end 71 and second end 72 and coupled to fixed structure by means of a joint device 75.
During operation, actuator group 33, through the respective axle and eccentric 40, rotates coupling bar 34 with respect to fixed frame 70 around bar rotation axis B. Coupling bar 40, in turn, actuates interaction rollers 24 between the first extreme position and the second extreme position.
According to a variant 23' of the control device as shown in Figure 8, coupling group 32 may comprise a transmission unit 76 for transforming an angular movement of the axle of actuator group 30 into a translatory linear movement of a connecting bar 41 coupled to coupling bar 34 for inducing the angular movement of coupling bar 34 with respect to fixed frame 70 around bar rotation axis C.
According to some embodiments, packaging machine 1 is designed such that the relative position of interaction rollers 24 is defined prior to starting operation and is not further modified during operation.
According to some alternative embodiments, the relative position of interaction rollers 24 is modified during operation, in particular in dependence of a measured orientation and/or alignment and/or angular position of tube 3.
Advantageously, according to such embodiments, packaging machine 1 comprises a sensor device configured to measure the orientation and/or alignment and/or angular position of tube 3, in particular of longitudinal seam portion 22 and control device 23 is configured to control the orientation and/or alignment and/or angular position of tube 3, in particular of longitudinal seam portion 22, in dependence of a value measured by the sensor device and such to maintain a desired orientation and/or alignment and/or angular position of tube 3, in particular longitudinal seam portion 22.
With particular reference to Figures 1 and 2, isolation chamber 7 may comprise a housing 50 delimiting inner environment 8 (i.e. housing 50 separates inner environment 8 from outer environment 9).
Preferentially, inner environment 8 may comprise (i.e. may contain) the sterile gas, more preferentially the sterile air, at a given pressure. Preferentially, the given pressure may be (slightly) above ambient pressure for reducing the risk of any contaminants entering inner environment 8. For example, the given pressure may be about 100 Pa to 500 Pa (0,001 bar to 0,005 bar) above ambient pressure.
Preferentially, packaging apparatus 1 may comprise a distribution device for feeding the sterile gas, preferentially the sterile air, into isolation chamber 7, in particular inner environment 8.
According to one or more embodiments of the present invention and with particular reference to Figure 2, packaging machine 1 may also comprise a delimiting element 51 placed, in use, within tube 3 and designed to divide tube 3, in use, into a first space 52 and a second space 53.
According to the embodiment shown, pressurization promoting device 30 comprises, in particular consist of, delimiting element 51. Indeed, by having delimiting element 51 it is possible to guarantee that tube 3 is pressurized. According to the example shown, pressurization of tube 3 is obtained by means of the sterile gas.
In particular, contact station 25 is arranged downstream of delimiting element 51 along tube advancement path Q.
Additionally, packaging machine 1 may also comprise a pressurizing device 54 configured to direct, preferentially to continuously direct, in use, a flow of sterile gas, preferentially a flow of sterile air, into tube 3, preferentially into second space 53, preferentially for obtaining a gas pressure within second space 53 being higher than a gas pressure within first space 52.
In more detail, first space 52 may be delimited by tube 3, preferentially the walls of tube 3, and delimiting element 51. Furthermore, first space 52 may open up into inner environment 8. More preferentially, delimiting element 51 may delimit first space 52 at a downstream portion, in particular a bottom portion, of first space 52 itself.
In more detail, second space 53 may be delimited, in use, by tube 3, in particular the walls of tube 3, delimiting element 51 and a transversal seal portion 90 provided at an axial end of tube 3.
In further detail, first space 52 may be arranged upstream of second space 53 along tube advancement path Q. Preferentially, first space 52 may be arranged upstream of delimiting element 51 along tube advancement path Q. In the specific example shown, second space 53 may be placed below first space 52 along a vertical direction.
Preferentially, second space 53 may define a high-pressure zone within tube 3 and first space 52 may define a low-pressure zone within tube 3.
In the context of the present application, high-pressure zone (i.e. second space 53) is to be understood such that the internal pressure lies in a range of about 5 kPa to 40 kPa (0,05 bar to 0,4 bar), in particular of about 10 kPa to 30 kPa (0,10 bar to 0,30 bar) above ambient pressure (i.e. the pressure within second space 53 lies in a range of about 5kPa to 40kPa (0,05 bar to 0,4 bar), in particular of about 10kPa to 30 kPa (0,10 bar to 0,30 bar) above ambient pressure). In other words, second space 53 is overpressurized with respect to first space 52.
Low-pressure zone (i.e. first space 52) is to be understood such that the pressure is slightly higher than the ambient pressure. In particular, slightly higher than the ambient pressure means that the pressure lies in a range between 100 Pa to 500 Pa (0,001 bar to 0,005 bar) above ambient pressure.
In further detail, first space 52 may be in (direct) fluidic connection with inner environment 8. Thus, sterile gas present in first space 52 can flow to inner environment 8.
Preferentially, tube 3 (and its intermediates) lie at least partially within isolation chamber 7 (in particular, within inner environment 8).
Preferentially, the pressure inside first space 52 may (substantially) equal the given pressure present in isolation chamber 7, preferentially in inner environment 8. Preferentially, the pressure inside first space 52 may range between 100 Pa to 500 Pa (0,001 bar to 0,005 bar) above ambient pressure.
Filling device 13, preferentially filling pipe 14, may be configured to direct the pourable product into second space 53. Thus, in use, second space 53 may contain the pourable product and the pressurized sterile gas. The pressurized sterile gas may provide for the required hydrostatic force needed for a correct forming of packages 2.
Advantageously, delimiting element 51 may be designed to provide, in use, for at least one fluidic channel 55, preferentially having an annular shape, for fluidically connecting second space 53 with first space 52 allowing for, in use, a leakage flow of sterile gas from second space 53 to first space 52. Preferentially, in use, the sterile gas leaks from second space 53 (the high-pressure zone) to first space 52 (the low-pressure zone) through fluidic channel 55. By providing for fluidic channel 55 it is possible to control the gas pressure within second space 53 with an increased accuracy. Preferentially delimiting element 51 may be designed such that, in use, fluidic channel 55 may be provided by a gap between the inner surface of tube 3 and delimiting element 51, preferentially a peripheral portion of delimiting element 51.
Preferentially, pressurizing device 54 may be configured to provide for a variable flow of sterile gas of about 10 to 200 Nm3/h, in particular of 20 to 180 Nm3/h, even more particular of about 25 to 150 Nm3/h.
Preferentially, pressurizing device 54 may be configured to vary the flow of sterile gas in dependence of the sterile gas flowing from second space 53 to first space 52.
Preferentially, pressurizing device 54 may be configured to control the gas pressure within second space 53 to range between 5 kPa to 40 kPa (0,05 bar to 0,40 bar), in particular between 10 kPa to 30 kPa (0,1 bar to 0,3 bar), above ambient pressure.
Preferentially, pressurizing device 54 may be configured to withdraw sterile gas from inner environment 8, more preferentially to pressurize (to compress) the sterile gas, and to direct the sterile gas, preferentially the pressurized (compressed) sterile gas, into second space 53.
Preferentially, pressurizing device 54 may comprise an aspiration device 56, such as a compressor, configured to generate aspiration forces so as to withdraw the sterile gas from inner environment 8, and preferentially to pressurize (to compress) the sterile gas and to direct the pressurized sterile gas into second space 53. For example, aspiration device 56 may be a rotary machine, more preferentially a compressor.
Preferably, pressurizing device 54 comprise a gas feeding pipe 80 being fluidically connected with aspiration device and second space 53 for directing the sterile gas into second space 53. In particular, gas feeding pipe 80 is directly fluidically connected with second space 53.
In more detail, gas feeding pipe 80 comprises at least a main portion 81, which, in use, extends within tube 3. In particular, main portion 81 extends parallel to main pipe portion 15 of filling pipe 14.
Even more particular, at least main portion 81 and main pipe portion 15 are coaxial to one another.
In the specific example shown, filling pipe 14 extends at least partially within gas feeding pipe 80. Alternatively, gas feeding pipe 14 could at least partially extend within filling pipe 80.
In more detail, at least main pipe portion 15 extends at least partially within main portion 81.
In particular, the cross-sectional diameter of main pipe portion 15 is smaller than the cross-section diameter of main portion 81.
Preferentially, gas feeding pipe 80 and filling pipe 14 define/delimit an annular conduit 83 for the sterile gas to be fed into second space 53. In particular, annular conduit 83 is delimited by the inner surface of gas feeding pipe 80 and the outer surface of filling pipe 14.
In other words, in use, the sterile gas is directed into second space 53 through annular conduit 83.
In use, packaging machine 1 executes the steps of:

advancing web 4 along advancement path P, by means of conveying device 5;
forming tube 3 from the advancing web 4, in particular by means of tube forming and sealing device 10;
longitudinally sealing tube 3, in particular by means of tube forming and sealing device 10;
advancing the tube 3 along tube advancement path Q;
filling tube 3 with a pourable product, in particular by means of filling device 13; and
forming and transversally sealing (and cutting) packages 2 from the advancing tube 3, in particular by means of package forming apparatus 16.

The method also comprises a step of controlling, during which control device 23 interacts with tube 3 at contact station 25 through interaction rollers 24 so as to orient and/or align and/or angularly position tube 3, in particular with respect to the receiving seats of at least one of sealing element 20 and counter-sealing element 21.
The advantages of packaging machine 1 according to the present invention will be clear from the foregoing description.
In particular, simple and efficient means of controlling the orientation and/or alignment and/or angular position of tube 3 is provided.
Furthermore, control device 23 comes along with a simple design allowing to easily maintain control device 23 itself.
Clearly, changes may be made to packaging machine 1 as described herein without, however, departing from the scope of protection as defined in the accompanying claims.
In the specific embodiment shown, pressurization of tube 3 is obtained by the sterile gas. Alternatively, pressurization of tube 3 may result from the pourable product filled into tube 3.
In order to maintain a desired pressure within tube 3, pressurization promoting device 30 may comprise a counter pressure flange arranged, in use, within tube 3. In this case, contact station 25 is arranged downstream of the counter pressure flange along tube advancement path Q.

Claims

Packaging machine (1) for forming packages (2) filled with a pourable product, comprising:
- a conveying device (5) configured to advance a web (4) of packaging material along a web advancement path (P);

- an isolation chamber (7) separating an inner environment (8) from an outer environment (9);

- a tube forming and sealing device (10) being at least partially arranged within the isolation chamber (7) and being configured to form a tube (3) from the, in use, advancing web (4) of packaging material and to longitudinally seal the tube (3); wherein the tube (3) has a longitudinal axis (A); wherein the conveying device (5) is configured to advance the tube (3) along a tube advancement path (Q);

- a filling device configured to fill the tube (3) with the pourable product;

- a package forming apparatus (16) configured to transversally seal the, in use, advancing tube (3) to form the packages (2) from the tube (3); and

- pressurization promoting device (30) configured to promote a pressurization of the tube (3);
wherein the packaging machine (1) further comprises a control device (23) configured to interact with the tube (3) and to control an orientation and/or alignment and/or angular position of the tube (3);

wherein the control device (23) comprises a pair of interaction rollers (24) configured to engage, in use, the tube (3) from opposite sides thereof at a contact station (25) arranged downstream of the pressurization promoting device (30) along the tube advancement path (Q);

wherein each interaction roller (24) is rotatable around a respective rotation axis (B);

wherein the control device (23) also comprises a movement unit (31) configured to modify relative positions of the interaction rollers (24) with respect to one another so as to modify relative positions of the respective rotation axes (B) of the interaction rollers (24) with respect to one another and with respect to an advancement direction (D) of the tube (3).
Packaging machine (1) according to claim 1, wherein the movement unit (31) is configured to move the interaction rollers (24) for modifying the relative positions of the interaction rollers (24) with respect to one another and with respect to the advancement direction (D) of the tube (3) to control an orientation and/or alignment and/or angular position of the tube (3) with respect a to the longitudinal axis (A) of the tube (3).
Packaging machine (1) according to claim 1 or 2, wherein the movement unit (31) is configured to move one of the interaction rollers (24) along a first path having a first direction component substantially parallel to the longitudinal axis (A) of the tube (3) and the other interaction roller (24) along a second path having a second direction component substantially parallel to the longitudinal axis (A) of the tube (3) and opposite to the first direction component.
Packaging machine (1) according to any one of the preceding claims, wherein the control device (23) comprises only two interaction rollers (24) interposing, in use, the tube (3) between one another.
Packaging machine (1) according to any one of the preceding claims, wherein the movement unit (31) is designed so as to be able to arrange the interaction rollers (24) in such a way that the rotation axes (B) of the interaction rollers (24) are parallel to one another and/or in such a way that the rotation axes (B) of the interaction rollers (24) are perpendicular to the longitudinal axis (A) of the tube (3).
Packaging machine (1) according to any one of the preceding claims, wherein the movement unit (31) is configured to move the interaction rollers (24) between a first extreme position and a second extreme position in which the rotation axes (B) of the interaction rollers (24) are not parallel to one another and/or the rotation axes (B) of the interaction rollers (24) are not perpendicular to the longitudinal axis (A) of the tube (3);
wherein an intermediate position is defined between the first extreme position and the second extreme position, in which the rotation axes (B) of the interaction rollers (24) are parallel to one another and/or the rotation axes (B) of the interaction rollers (24) are perpendicular to the longitudinal axis (A) of the tube (3).
Packaging machine (1) according to any one of the preceding claims, wherein the movement unit (31) comprises a coupling group (32) movably carrying the interaction rollers (24) and an actuator group (33) operatively connected to the coupling group (32) and configured to actuate a movement of the interaction rollers (24).
Packaging machine (1) according to claim 7, wherein the coupling group (32) comprises a fixed frame (70) and a coupling bar (34) coupled to fixed frame 70 and movably carrying the interaction rollers (24);
wherein the actuator group (33) is configured to actuate a rotation of the coupling bar (34) around a respective bar rotation axis (C).
Packaging machine (1) according to claim 8, wherein each interaction roller (24) comprises a shaft (36) movably housed within a respective housing seat (35) of the coupling bar (34).
Packaging machine (1) according to claim 8 or 9, wherein the coupling group (32) also comprises an eccentric (40) operatively connected to the coupling bar (34) and to the actuator group (33);
wherein the actuator group (33) is configured to actuate a rotation of the coupling bar (34) around the bar rotation axis (C) by rotating the eccentric (40).
Packaging machine (1) according to any one of the preceding claims, wherein the pressurization promoting device (30) comprises a delimiting element (51) arranged, in use, within the tube (3) and designed to divide the tube (3) in a first space (52) being in fluidic connection with the inner environment (8) and a second space (53) being arranged downstream of the first space (52) along the tube advancement path (Q);
wherein the packaging machine (1) further comprises a pressurizing device (54) configured to direct, in use, a flow of gas into the second space (52);

wherein the contact station (25) is arranged downstream of the delimiting element (51) along the tube advancement path (Q).
Packaging machine (1) according to claim 11, wherein the pressurizing device (54) comprises an aspiration device (56) configured to direct pressurized gas into the second space (53).
Packaging machine (1) according to any one of claims 1 to 10, wherein the pressurization promoting device (30) comprises a counter pressure flange arranged, in use, within the tube (3);
wherein the contact station (25) is arranged downstream of the counter pressure flange along the tube advancement path (Q).
Packaging machine (1) according to any one of the preceding claims, wherein the tube (3) comprises a longitudinal seam portion (22);
wherein the control device (23) is configured to control an orientation and/or alignment and/or angular position of the longitudinal seam portion (22).
Packaging machine (1) according to claim 14, and further comprising a sensor device configured to measure the position of the longitudinal seam portion;
wherein the control device (23) is configured to control the orientation and/or alignment and/or angular position of the longitudinal seam portion (22) in dependence of a value measured by the sensor device and such to maintain a desired orientation and/or alignment and/or angular position of the longitudinal seam portion (22).