Packaging machine and method for producing sealed packaging containers

Abstract

A packaging machine (1) for producing sealed packages (2) of pourable products from a web (4) of packaging material, comprising: conveying means (5) for advancing the web (4) of packaging material along a web advancement path (P) to at least a tube forming station (6) where the web (4) of packaging material is formed into a tube (3), and for advancing the tube (3) along a tube advancement path (Q); an isolation housing (12) having a main chamber (14) and an auxiliary chamber (15) located downstream of the main chamber (14) along the tube advancement path (Q); A packaging machine (1) is described that includes a tube forming and sealing device (16) disposed at least partially within the chamber (14) and configured to form and longitudinally seal a tube (3) within the main chamber (14), a filling device (17) for filling the tube (3) with a pourable product, and a pressure control device (25) configured to control a first pressure in the main chamber (14) and a second pressure in the auxiliary chamber (15) such that the first pressure is greater than the second pressure and the first pressure and the second pressure are both greater than ambient pressure. [Selected figure] Figure 2

Description

[Technical Field]

[0001] The present invention relates to a packaging machine for producing sealed packages of pourable products, in particular pourable food products.

[0002] The present invention also relates to a method for producing a sealed package of a pourable product, in particular a pourable food product. [Background technology]

[0003] As is known, many liquid or pourable food products, such as fruit juice, UHT (ultra-high temperature processed) milk, wine, tomato sauce, etc., are sold in packaging containers made of sterilized packaging material.

[0004] A typical example is the parallelepiped-shaped packaging container for liquids or pourable foods known as Tetra Brik Aseptic®, which is made by sealing and folding a laminated strip packaging material. The packaging material has a multi-layer structure including a base layer, for example, of paper, covered on both sides with layers of heat-sealable plastic material, for example, polyethylene. In the case of aseptic packaging containers for long-storage products such as UHT milk, the packaging material also includes a layer of oxygen barrier material (oxygen barrier layer), for example, a layer of aluminum foil, which is superimposed on the layer of heat-sealable plastic material and then covered with another layer of heat-sealable plastic material that forms the inner surface of the packaging container that ultimately contacts the food.

[0005] This type of packaging container is typically produced on a fully automatic packaging machine that advances a web of packaging material from a magazine unit through a sterilization device for sterilizing the web of packaging material into an isolation housing (a closed, at least partially sterile environment) where the sterilized web of packaging material is maintained and advanced. During the advancement of the web of packaging material through the main chamber of the isolation housing, the web of packaging material is longitudinally folded and sealed to form a tube with a longitudinal seal, and the tube is fed further along the vertical advance direction and passes through the auxiliary chamber of the isolation housing.

[0006] To complete the forming operation, while advancing along a vertical advance direction, the tube is filled with a sterilized or sterilized pourable product, in particular a pourable food product, then formed to at least partially define the final shape of the packaging container, transversely sealed and subsequently cut along equally spaced cross sections in a packaging container forming unit of the packaging machine.

[0007] Pillow-type packages are thus obtained in the packaging machine, each having a longitudinal seal strip, a top transverse seal strip and a bottom transverse seal strip.

[0008] A drawback of known packaging machines is that immediately after sealing, the longitudinal seal of the tube is still warm and therefore more fragile than a fully cooled one. This is typically the case when the tube advances through the downstream part of the main chamber and the upstream part of the auxiliary chamber. Therefore, the entire process needs to be controlled to avoid or at least limit the possibility of the longitudinal seal collapsing (i.e. opening and / or losing its integrity) during the tube's advancement as a result of forces acting on the tube itself.

[0009] Therefore, there is a need in the art to provide a packaging machine that reduces the risk of longitudinal seal collapse during operation of the packaging machine.

[0010] There is also a need to provide packaging machines that can operate at increased throughput rates (increased number of packaging containers per hour that can be produced). Summary of the Invention [Problem to be solved by the invention]

[0011] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a packaging machine which overcomes in a simple manner at least one of the aforementioned drawbacks.

[0012] In particular, it is an object of the present invention to provide a packaging machine that makes it possible to reduce the risk that the longitudinal seal of the formed tube may collapse.

[0013] A further object of the present invention is to provide a method for producing sealed packaging containers which overcomes in a simple manner at least one of the aforementioned drawbacks. [Means for solving the problem]

[0014] According to the present invention, there is provided a packaging machine and a method for producing sealed packaging containers according to the independent claims.

[0015] Preferred embodiments are claimed in the dependent claims.

[0016] Non-limiting embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a schematic diagram, with parts removed for clarity, of a packaging machine according to the present invention; [Figure 2] FIG. 2 is a schematic diagram of some portions of the packaging machine of FIG. 1 with parts removed for clarity. [Figure 3] 2 is a cross-sectional view of a detail of the packaging machine of FIG. 1 with parts removed for clarity; FIG. [Figure 4] FIG. 2 is a perspective view of a detail of the packaging machine of FIG. 1 with parts removed for clarity. [Figure 5] 2 is a cross-sectional and partially exploded view of another detail of the packaging machine of FIG. 1, with parts removed for clarity. [Figure 6] 2 is a cross-sectional and partially exploded view of yet another detail of the packaging machine of FIG. 1, with parts removed for clarity. DETAILED DESCRIPTION OF THE INVENTION

[0018] Number 1 generally indicates a packaging machine for producing sealed packaging containers 2 of pourable products, in particular pourable food products such as pasteurized milk, fruit juice, wine, tomato sauce, etc., from a tube 3 of a web 4 of packaging material. In particular, in use, the tube 3 extends along a longitudinal axis and has a particularly vertical orientation.

[0019] The web 4 comprises at least a layer of fibrous material, in particular paper, covered on both sides with respective layers of heat-sealable plastic material, for example polyethylene.

[0020] In a non-limiting embodiment, web 4 also includes a layer of gas and light barrier material, such as aluminum foil or ethylene vinyl alcohol (EVOH) film, and at least first and second layers of heat-sealable plastic material. The layer of gas and light barrier material is overlaid on the first layer of heat-sealable plastic material and covered with a second layer of heat-sealable plastic material. The second layer of heat-sealable plastic material forms the interior surface of package 2 that ultimately contacts the filled pourable food product.

[0021] More specifically, web 4 includes a first side and a second side, and in particular, the first side is the side of web 4 that forms the inner surface of the formed packaging container 2 that ultimately comes into contact with the filled pourable food product.

[0022] A typical package 2 obtained by the packaging machine 1 includes a longitudinal seam and a pair of transverse seal strips, in particular a transverse top seal strip and a transverse bottom seal strip.

[0023] In particular, with reference to FIG. 1 , packaging machine 1 is configured to advance web 4 along web advancement path P, preferably sterilize web 4 while advancing along path P, form tube 3 from web 4, fill tube 3, and preferentially form a single packaging container 2 from filled tube 3.

[0024] Preferentially, the packaging machine 1 comprises: - conveying means 5 configured to advance the web 4 along a web advancement path P to at least a tube forming station 6 where the web 4 is formed into a tube 3 in use, the conveying means 5 being configured to advance the tube 3 along a tube advancement path Q; - a sterilization device 7 for sterilizing at least a portion of the web 4, preferentially at least the first side, and even more preferentially the first side and the second side, in a sterilization station 8 arranged upstream of the tube forming station 6 along the web advancement path P; - an isolation housing 12 extending along a longitudinal axis A, in particular having a vertical orientation, and having at least a main chamber 14 and an auxiliary chamber 15, the latter being arranged downstream of the main chamber 14 along the tube advance path Q; a tube forming and sealing device 16 arranged at least partially within the isolation housing 12, in particular the main chamber 14, and configured to form and longitudinally seal the tube 3 at the tube forming station 6 within at least a portion of the isolation housing 12, in particular the main chamber 14; and - a filling device 17 for filling the tubes 3 with a pourable product;

[0025] Preferentially, the packaging machine 1 also includes a packaging container forming unit 18 adapted to at least form and transversely seal the tube 3, in particular during advancement of the tube 3 along the tube advance path Q, and preferentially cut the tube 3 transversely between successive packaging containers 2.

[0026] In a preferred, non-limiting embodiment, the packaging machine 1 also includes a magazine unit adapted to receive and present the web 4 at the receiving station 20 .

[0027] Advantageously, the packaging machine 1 also comprises a pressure control device 25 adapted (configured) to control the pressure within at least part of the isolation housing 12, in particular within at least the main chamber 14, and preferentially also within the auxiliary chamber 15.

[0028] More specifically, the sterilization station 8 is located upstream of the tube forming station 6 along the web advancement path P. In other words, the sterilization device 7 is located upstream of the isolation housing 12 along the path P.

[0029] Preferentially, the sterilizer 7 is arranged along the path P downstream of the magazine unit.

[0030] In particular, the package forming unit 18 is disposed along path Q downstream of the isolation housing 12 and the tube forming and sealing device 16 .

[0031] More particularly, the conveying means 5 is adapted to advance the tubes 3 and intermediates of the tubes 3 along the path Q, in particular from the tube forming station 6 through part of the main chamber 14 to and through the auxiliary chamber 15, and even more particularly towards and at least partially through the packaging container forming unit 18, in a manner known as such.

[0032] In particular, the intermediate tube 3 refers to the configuration of the web 4 before obtaining the tubular structure and after the folding of the web 4 has begun by the tube forming and sealing device 16. In other words, the intermediate tube 3 is the result of gradually folding the web 4 to obtain the tube 3, in particular by overlapping the opposite edges of the web 4 with each other.

[0033] In particular, with reference to Figure 2, the sterilization apparatus 7 is configured to sterilize the web 4, particularly the first side, and even more particularly the second side, by physical sterilization, such as by sterilizing radiation, particularly electromagnetic radiation, and even more particularly electron beam radiation.

[0034] Alternatively, the sterilizer 7 may be configured to sterilize the web 4, in particular the first side, and more particularly also the second side, by chemical sterilization, in particular hydrogen peroxide.

[0035] More particularly, according to a particular, non-limiting exemplary embodiment disclosed, the sterilization device 7 comprises an irradiation device 26 arranged in the region of the sterilization station 8, which irradiation device 26 is adapted to sterilize at least the first surface, and preferentially also the second surface, by directing sterilizing radiation, in particular electromagnetic radiation, and even more particularly electron beam radiation, towards at least the first surface, and preferentially also the second surface, during the advancement of the web 4 along the sterile portion of the path P; and - at least one shielded chamber 27 housing the irradiation device 26, the shielded chamber 27 including an advancement channel 28 through which the web 4 advances, in particular during use, while sterilizing the web 4, in particular the first side and more particularly also the second side.

[0036] More specifically, the irradiation device 26 includes: at least a first radiation emitter, in particular a first electron beam emitter 29, configured to direct sterilizing radiation, in particular electromagnetic radiation, even more particularly electron beam radiation, towards the first surface during use, and - a second radiation emitter, in particular a second electron beam emitter 30, which is preferentially also configured to direct sterilizing radiation, in particular electromagnetic radiation, even more particularly electron beam radiation, towards the second surface during use.

[0037] Preferably, electron beam emitter 29 and electron beam emitter 30 are arranged side by side and spaced apart from each other so that at least a portion of forward channel 28 is interposed between electron beam emitter 29 and electron beam emitter 30.

[0038] With particular reference to FIGS. 1 and 2, isolation housing 12 is configured to separate an internal environment 31, particularly having at least one sterile portion, from an external environment 32.

[0039] More specifically, the main chamber 14 is the portion of the isolation housing 12 where the web 4 is formed into the tube 3 during use and where the web 4 is longitudinally sealed during use. In other words, the main chamber 14 includes the portion of the tube forming and sealing apparatus 16 that directly interacts with the web 4 and the tube 3 itself to form and longitudinally seal the tube 3.

[0040] More particularly, the auxiliary chamber 15 is disposed downstream (directly) of the main chamber 14 along the tube advancement path Q. In use, the tube 3 advances through the auxiliary chamber 15 after its formation and after its longitudinal sealing. In particular, in use, the formed and longitudinally sealed tube 3 advances directly from the main chamber 14 to the auxiliary chamber 15 (i.e., there is no further chamber disposed between the main chamber 14 and the auxiliary chamber).

[0041] In particular, the main chamber 14 and the auxiliary chamber 15 are connected to each other, and more particularly, are directly connected.

[0042] Preferentially, the main chambers 14 include respective main interior spaces 33 that define a part of the interior environment 31, in particular a sterile part of the interior environment 31. In other words, the main chambers 14 are preferentially sterile main chambers 14.

[0043] Further, in other words, during use, the web 4 advances through a portion of the main chamber 14 before being formed into the tube 3. Preferably, the interior space 31 is sterile, so that the sterility of the web 4 and the tube 3 is maintained.

[0044] Preferably, the auxiliary chamber 15 includes an auxiliary interior space 34 that defines a further portion of the interior environment 31. The auxiliary interior space 34 is not necessarily a sterile environment.

[0045] Preferably, the isolation housing 12 also includes a containment chamber 35 that is positioned downstream of the auxiliary chamber 15 along the tube advance path Q and is adapted (configured) to receive gas that leaks from the auxiliary chamber 15 (that is present within the auxiliary chamber 15 itself).

[0046] In particular, the containment chamber 35 is connected, in particular directly connected, to the auxiliary chamber 15. In other words, during use, the tube 3 advances from the auxiliary chamber 15 to the containment chamber 35.

[0047] In the preferred non-limiting embodiment shown, the isolation housing 12 includes an inlet portion 36 for receiving the web 4 and an outlet portion 37 for enabling the supply of the tube 3 from the isolation housing 12 itself, in particular to the packaging container forming unit 18.

[0048] Preferentially, the main chamber 14 includes an inlet portion 36 .

[0049] Preferably, the containment chamber 35 defines (includes) an outlet portion 37 .

[0050] In the preferred non-limiting embodiment shown, the sterilizer 7 is coupled, particularly connected, to the main chamber 14 , particularly so that the web 4 advances from the sterilizer 7 to the main chamber 14 .

[0051] Preferably, the isolation housing 12 also includes at least one main isolation wall 41 for separating the main chamber 14 and the auxiliary chamber 15 from each other.

[0052] In particular, the main separation wall 41 is transverse to the axis A. Even more particularly, the main separation wall 41 has a substantially horizontal orientation.

[0053] In particular, the main separation wall 41 is interposed between the main chamber 14 and the auxiliary chamber 15. In other words, the main separation wall 41 is disposed near the downstream portion of the main chamber 14 (with respect to path Q) and near the upstream portion of the auxiliary chamber 15 (with respect to path Q).

[0054] In particular, the portion of the tube forming and sealing apparatus 16 located within the main chamber 14 is located upstream of the main separation wall 41 along path Q.

[0055] In particular, with reference to Figures 2 to 4, the isolation housing 12, and in particular the main isolation wall 41, includes a main passage 42, in particular a (circular) hole, in the main isolation wall 41 which, in use, allows passage of the advancing tube 3 from the main chamber 14 to the auxiliary chamber 15.

[0056] Preferentially, the packaging machine 1, in particular the isolation housing 12, comprises at least one main seal assembly 43 configured to seal the main passageway 42 during use, in particular in cooperation with the tube 3. In particular, the main seal assembly 43 is configured to impede, in particular (substantially) prevent, gas exchange between the main chamber 14 and the auxiliary chamber 15 via the main passageway 42. It should be noted, however, that (uncontrollable) leakage flows may still exist between the main chamber 14 and the auxiliary chamber 15 via the main passageway 42.

[0057] More specifically, the main seal assembly 43 is coupled to, and in particular at least partially contacts, the main separation wall 41 in the region of the main passage 42. In particular, the main seal assembly 43 is configured to also be coupled to, and even more specifically contact, the tube 3 in use.

[0058] In other words, the main seal assembly 43 is configured to cooperate with the main separation wall 41 and the tube 3 to seal the main passage 42 so as to impede, in particular (substantially) prevent, gas exchange between the main chamber 14 and the auxiliary chamber 15 via the main passage 42.

[0059] Preferentially, the primary seal assembly 43 is configured to at least partially guide the advancement of the tube 3 .

[0060] In particular, with reference to Figures 3 to 5, the primary seal assembly 43 includes at least one seal element, in particular at least one gasket 44 configured to interact with and contact the advancing tube 3 during use, and a carrier structure 45 that supports the gasket 44.

[0061] Preferentially, the carrier structure 45 is configured or arranged to be located on the main separation wall 41, in particular within the main chamber 14. In particular, the main seal assembly 43 is configured to cooperate with the separation wall 41 and the tube 3 advancing therethrough in use to seal the main passageway 42.

[0062] More specifically, the main passageway 42 is sealed by the cooperation of the carrier structure 45 with the main separation wall 41 and the cooperation of the gasket 44 with the tube 3 .

[0063] More specifically, the main separation wall 41 includes an engagement surface 47 that particularly surrounds the main passage 42, and the carrier structure 45 includes an interaction surface 48 that particularly surrounds the gasket 44 and is configured to be positioned on the engagement surface 47.

[0064] In particular, the engagement surface 47 is defined by a (annular) recess in the main separation wall 41. Preferentially, the interaction surface 48 is at least partially complementary to the engagement surface 47.

[0065] Preferentially, the primary seal assembly 43 is configured to at least partially guide the advancement of the tube 3. In particular, the primary seal assembly 43 is configured to remain substantially immobile relative to the advancing tube 3 during use.

[0066] Even more preferentially, the carrier structure 45, in particular the interaction surface 48, is coupled to the main separation wall 41, in particular the engagement surface 47, such that, during use, any movement of the main seal assembly 43, in particular the carrier structure 45 together with the gasket 44, in a direction transverse to the axis A is (substantially) prevented.

[0067] Preferably, carrier structure 45 also includes a clamping element 49 configured to clamp a portion of primary separation wall 41 between clamping element 49 and interaction surface 48. In this way, it is further ensured that primary seal assembly 43 is immobilized during use.

[0068] In this way, it is ensured that the primary seal assembly 43 is able to at least partially guide the advancement of the tube 3 .

[0069] With particular reference to FIGS. 2 to 4 and 6, the isolation chamber 12 further includes at least one auxiliary isolation wall 50 spaced apart from the main isolation wall 41 and further defining the boundary of the auxiliary chamber 15 .

[0070] In particular, the auxiliary separating wall 50 is transverse to the axis A. In particular, the auxiliary separating wall 50 has a substantially horizontal orientation, in particular similar to the main separating wall 41.

[0071] More specifically, the auxiliary separation wall 50 is disposed downstream of the main separation wall 41 along the path Q. In particular, the auxiliary separation wall 50 and the main separation wall 41 bound the auxiliary chamber 15 along the axis A.

[0072] Preferentially, the auxiliary separation wall 50 is located near the downstream part of the auxiliary chamber 15 (with respect to the path Q) and in particular defines the end of the auxiliary chamber 15 .

[0073] In the particular exemplary embodiment disclosed, the main separation wall 41 bounds the auxiliary chamber 15 in the region of the upstream portion of the auxiliary chamber 15 itself.

[0074] In the preferred non-limiting embodiment shown, the isolation housing 12, in particular the auxiliary separation wall 50, includes an auxiliary passage 51, in particular a (circular) hole, in the auxiliary separation wall 50 which, during use, allows passage of the advancing tube 3 from the auxiliary chamber 15, in particular to the package forming unit 18, and even more particularly first to the containment chamber 35 and then to the package forming unit 18.

[0075] Preferentially, the auxiliary passage 51 and the main passage 42 are arranged coaxially with respect to one another.

[0076] In the disclosed preferred non-limiting embodiment, the packaging machine 1, and in particular the isolation housing 12, includes an auxiliary seal assembly 52 configured to seal the auxiliary passage 51 in use to impede, in particular (substantially) prevent, the flow of gas into or out of the auxiliary chamber 15 via the auxiliary passage 51. However, it should be noted that (uncontrollable) leakage flow may still exist via the auxiliary passage 51.

[0077] In particular, the auxiliary seal assembly 52 is coupled to, and in particular at least partially contacts, the auxiliary separation wall 50 in the region of the auxiliary passage 51 in order to seal the auxiliary passage 51 in use. In particular, the auxiliary seal assembly 52 is configured to also couple to, and even more particularly contact, the tube 3 in use.

[0078] In other words, the auxiliary seal assembly 52 is configured to cooperate with the auxiliary separation wall 50 and the tube 3 advancing in use to seal the auxiliary passage 51 so as to at least impede, and in particular (substantially) prevent, the outflow of gas from and / or the inflow of gas into the auxiliary chamber 15 via the auxiliary passage 51. In particular, by providing the auxiliary seal assembly 52, (substantial) gas exchange between the auxiliary chamber 15 and the containment chamber 35 via the auxiliary passage 51 is impeded, in particular prevented.

[0079] The secondary seal assembly 52 is similar to the primary seal assembly 43. Therefore, hereinafter, the secondary seal assembly 52 will be described only with respect to its differences from the primary seal assembly 43, using the same references for similar or equivalent parts.

[0080] In particular, the auxiliary seal assembly 52 differs from the primary seal assembly 43 in that at least a portion of the auxiliary seal assembly 52 is movable in a direction D1 transverse to the longitudinal axis A, and in particular in a direction D1 perpendicular to the longitudinal axis A, as a result of interaction with the advancing tube 3 during use.

[0081] Even more specifically, the auxiliary seal assembly 52 is configured to be movable within a plane H1 transverse to the longitudinal axis A, and particularly within a plane H1 perpendicular to the longitudinal axis A. In particular, during use, the auxiliary seal assembly 52 moves within the plane H1 as a result of interaction with the advancing tube 3.

[0082] More specifically, the plane H1 is substantially defined by the respective engagement surfaces 47 and the respective interaction surfaces 48.

[0083] Preferably, the carrier structure 45 ′ (which is substantially similar to the carrier structure 45 ) of each of the auxiliary seal assemblies 52 is floatingly coupled to the auxiliary separation wall 50 in the region of the auxiliary passage 51 .

[0084] Even more preferably, the respective carrier structure 45' of the auxiliary seal assembly 52, in particular the respective carrier structure 45' together with at least the gasket 44, is configured to move in direction D1, in particular in plane H1, during use, in particular as a result of interaction with the advancing tube 3 during use. In particular, it is known that during use the tube 3 may exhibit oscillation, i.e. movement, in a respective direction transverse to, in particular in a respective direction perpendicular to, the axis A (in other words, the portion of the path Q during which the tube 3 advances within the auxiliary chamber 15), and that as a result of interaction, in particular contact, between the auxiliary seal assembly 52, in particular at least the gasket 44, and the tube 3, the oscillation is transmitted to the auxiliary seal assembly 52, in particular the carrier structure 45'.

[0085] In this way, the auxiliary seal assembly 52 is configured, in use, to avoid guiding and binding the advancing tube 3. Further, in other words, the auxiliary seal assembly 52, and in particular the respective carrier structure 45', is configured, in use, to move in a direction D1 transverse to, and preferentially perpendicular to, the advancing tube 3, and in particular in a plane H1.

[0086] More particularly, the auxiliary separating wall 50 comprises an engagement surface 53 which in particular surrounds the auxiliary passage 51. Preferentially, the engagement surface 53 is defined by a (annular) recess in the auxiliary separating wall 50.

[0087] Preferentially, the carrier structure 45′, in particular the respective interaction surface 48 of each carrier structure 45′, is or can be movably arranged on the engagement surface 53, in particular such that each carrier structure 45′ is movable along the direction D1, in particular in the plane H1. In particular, the carrier structure 45′, and even more particularly the respective interaction surface 48, is movable on and relative to the engagement surface 53.

[0088] In the exemplary embodiment shown, the respective cross-sectional dimensions of each interaction surface 48 are smaller than the respective cross-sectional dimensions of the recesses defining the engagement surfaces 53 .

[0089] In other words, the auxiliary seal assembly 52, in particular the respective carrier structure 45', and even more particularly the respective interaction surface 48, is coupled with play to the auxiliary separation wall 50 in the region of the auxiliary passage 51, in particular the engagement surface 53, and even more particularly the recess defining the engagement surface 53, in particular along the direction D1, and even more particularly in the plane H1.

[0090] In a preferred, non-limiting embodiment, the interaction surface 48 of the carrier structure 45' is a smooth surface that allows for reduced friction between the engagement surface 53 and the interaction surface 48 itself.

[0091] The auxiliary seal assembly 52 also differs from the main separation wall 41 in that the auxiliary seal assembly 52 preferably also includes a second seal element, in particular a second gasket 54 arranged coaxially with respect to the respective gasket 44 and configured to contact the advancing tube 3 during use.

[0092] In an alternative embodiment, the secondary seal assembly 52 includes only the gasket 44 .

[0093] In yet another alternative embodiment, the secondary seal assembly 52 includes multiple gaskets, particularly three or more gaskets.

[0094] In particular, with reference to Figures 2 and 3, the confinement chamber 35 includes an outlet passage 56, in particular coaxial with the auxiliary passage 51, configured to allow the tube 3 to exit the confinement chamber 35 and in particular enter the package forming unit 18.

[0095] In particular, the containment chamber 35 has an exit passage 56 and includes an end wall 57 that is transverse to the axis A. Preferably, the end wall 57 has a substantially horizontal orientation.

[0096] Preferentially, the outlet passage 56 is defined by a (circular) hole provided in the end wall 57 .

[0097] Preferentially, the isolation chamber 12, in particular the containment chamber 35, includes a final seal assembly 58 configured to seal the outlet passage 56 in use, in particular in cooperation with the tube 3, to at least impede, in particular (substantially) prevent, the flow of gas into or out of the containment chamber 35 via the outlet passage 56. However, one or more (uncontrollable) leak flows through the outlet passage 56 may still exist.

[0098] Preferentially, the final seal assembly 58 is coupled to the end wall 57 in the region of the outlet passage 56 and is configured to couple to, and more particularly contact, the tube 3 in use. In particular, the final seal assembly 58 is configured to cooperate with the end wall 57 and the tube 3 advancing in use to seal the outlet passage 56.

[0099] Final seal assembly 58 is similar to secondary seal assembly 52. Therefore, hereinafter, final seal assembly 58 will be described only with respect to its differences from secondary seal assembly 52, using the same references for similar or equivalent parts.

[0100] Notably, final seal assembly 58 includes only gasket 44. However, in alternative embodiments, final seal assembly 58 may include one or more additional sealing elements (gaskets).

[0101] Furthermore, the outlet passage 56 is similar to the auxiliary passage 51. Therefore, in the following, the outlet passage 56 will be described only with respect to its differences from the auxiliary passage 51, using the same references for similar or equivalent parts.

[0102] In particular, the difference is that the outlet passage 56 is contained in the end wall 57 .

[0103] It should be emphasized that, like the auxiliary seal assembly 52, the final seal assembly 58 is configured to move along a direction D2 that is transverse to the axis A, particularly perpendicular to the axis A, particularly parallel to the direction D1. In particular, the final seal assembly 58 is configured to move in a plane H2 that is transverse to the axis A, particularly perpendicular to the axis A. Like the auxiliary seal assembly 52, the final seal assembly 58 is configured to move in the direction D2, particularly in the plane H2, during use as a result of interaction, particularly contact, with the advancing tube 3. In particular, the plane H2 is spaced apart from and parallel to the plane H1.

[0104] Preferentially, but not necessarily, the plane H2 is substantially defined by the respective engagement surface 47 and the respective interaction surface 48.

[0105] In particular, each carrier structure 45′ of final seal assembly 58 is floatingly coupled to end wall 57. In particular, each carrier structure 45′ of final seal assembly 58, and more particularly each interaction surface 48, is movable on and relative to each engagement surface 53.

[0106] In the disclosed preferred embodiment, the isolation housing 12 further includes a plurality of side walls 59 for defining the interior environment 31. In particular, the side walls 59 extend substantially parallel to the axis A, i.e., preferably have a perpendicular orientation.

[0107] In particular, with reference to FIG. 1 , the tube forming and sealing apparatus 16 includes at least a tube forming group 61 configured to form a tube 3 from the web 4 and at least a sealing head 62 configured to longitudinally seal the tube 3, particularly the tube 3 disposed within the main chamber 14.

[0108] More specifically, a tube forming group 61 and a sealing head 63 are disposed within the main chamber 14 .

[0109] 1 includes two forming ring assemblies 63 arranged in the main chamber 14 and adapted to gradually fold the web 4 into the tube 3, particularly by overlapping the respective lateral edges of the web 4. In particular, the forming ring assemblies 63 are arranged in parallel, spaced apart planes, particularly orthogonal to the axis A and, more particularly, having a substantially horizontal orientation. Preferably, the other downstream-arranged forming ring assembly 63 is also designed to exert a mechanical force on the tube 3, particularly to promote longitudinal sealing of the tube 3.

[0110] In particular, with reference to Figures 1 and 2, the filling device 17 includes at least a filling tube 64 that is fluidly connected to a pourable product storage tank (not shown, not known as such) and that is partially disposed within the tube 3 to supply the pourable product to the tube 3.

[0111] More particularly, the fill tube 64 has an L-shaped configuration arranged such that a linear main tube portion 65 of the fill tube 64 extends within the tube 3 parallel to the axis A. Notably, the fill tube 64 also includes a curved portion 66 connected to the linear main tube portion 65 and disposed within the main chamber 14.

[0112] Even more particularly, the linear main tube portion 65 has portions which extend into the main chamber 14 and the auxiliary chamber 15 respectively, preferentially into the containment chamber 35 and even more preferentially into the package forming unit 18.

[0113] In a preferred, non-limiting embodiment, the linear main tube portion 65 includes at least one upstream section 67 and at least one downstream section 68 having an outlet opening through which, in use, the pourable product exits and enters the tube 3, the upstream section 67 and the downstream section 68 being connected to one another. In particular, the upstream section 67 is also connected to the curved portion 66.

[0114] More specifically, the upstream section 67 extends within the main chamber 14 and into the auxiliary chamber 15, and preferably the downstream section 68 extends within the auxiliary chamber 15, particularly through the containment chamber 35 into the package forming unit 18.

[0115] Preferentially, the junction between the upstream section 67 and the downstream section 68 is in the region of the main passage 42 .

[0116] In particular, with reference to Figure 2, the packaging container forming unit 18 includes a plurality of complementary pairs (only one pair is shown) of operating units 69 configured to at least form and transversely seal the packaging container 2, and in particular also to transversely cut it.

[0117] Advantageously, the pressure control device 25 is adapted (configured) to control at least a first pressure in the main chamber 14 and at least a second pressure in the auxiliary chamber 15 .

[0118] In particular, the first pressure is greater than the second pressure, and the first pressure and the second pressure are both greater than ambient pressure.

[0119] In particular, in this manner, the pressure controller 25 is configured to control the first pressure and the second pressure so as to prevent contaminants from entering the main chamber 14 from the external environment 32 and / or the auxiliary chamber 15 .

[0120] In a preferred, non-limiting embodiment, the pressure controller 25 is configured to control the first pressure to be in the range of 200 Pa to 10,000 Pa (2 mbar to 100 mbar) above ambient pressure, preferentially in the range of 500 Pa to 9,000 Pa (5 mbar to 90 mbar) above ambient pressure, and even more preferentially in the range of 800 Pa to 8,000 Pa (8 mbar to 80 mbar) above ambient pressure.

[0121] In particular, pressure controller 25 is configured to control the first pressure and the second pressure such that the pressure difference between the first pressure and the second pressure is in the range of 500 Pa to 2500 Pa (5 mbar to 25 mbar), in particular 800 Pa to 1200 Pa (8 mbar to 12 mbar). Even more particularly, pressure controller 25 is also configured to control the first pressure to be more than 500 Pa, preferably more than 800 Pa, above ambient pressure.

[0122] More specifically, the pressure control device 25 includes: a gas regulation unit 73 configured to direct pressurized (sterilizing) gas into the main chamber 14 to control the first pressure; and a flow conducting portion 74 fluidly connecting the main chamber 14 with the auxiliary chamber 15 and configured to allow a (controlled) flow of gas from the main chamber 14 to the auxiliary chamber 15, in particular to control the second pressure.

[0123] Even more specifically, the gas regulation unit 73 includes an injection tube 75 disposed at least partially within the main chamber 14 and configured to inject (sterilizing) gas into the main chamber 14, and preferably also includes a control valve 76 for controlling the flow of gas within the injection tube 75.

[0124] More specifically, injection tube 75 extends at least partially into main chamber 14 parallel to axis A and includes a plurality of nozzles for injecting pressurized gas into main chamber 14 .

[0125] In a preferred, non-limiting embodiment, the gas regulation unit 73 is further configured to at least pressurize the gas, and even more preferentially to pressurize and sterilize the gas, particularly at least prior to injection into the main chamber 14 .

[0126] In a preferred, non-limiting embodiment, the gas regulation unit 73 also includes a further injection tube 77 configured to inject pressurized (sterilizing) gas into the sterilizer 7, in particular into the shielded chamber 27. Preferentially, the injection tube 77 is configured to inject gas into the region of the interface between the sterilizer 7 and the isolation housing 12.

[0127] In a preferred, non-limiting embodiment, the pressure control device 25 also includes a control valve 78, preferably a ball valve, disposed within the flow conducting portion 74 and configured to control the flow of gas from the main chamber 14 to the auxiliary chamber 15 through the flow conducting portion 74, in particular to control the second pressure.

[0128] Advantageously, but not necessarily, the pressure control device 25 further comprises a measurement unit 79 configured to measure and / or determine the first pressure (pressure in the main chamber 14).

[0129] Preferably, the pressure control device 25 is configured to control the control valve 76 as a function of the first pressure measured and / or determined by the measuring unit 79, in particular to control the first pressure to be in the range of 200 Pa to 10,000 Pa above ambient pressure, preferentially 500 Pa to 9,000 Pa above ambient pressure, and even more preferentially 800 Pa to 8,000 Pa above ambient pressure.

[0130] In a preferred, non-limiting embodiment, the auxiliary chamber 15 includes an exit orifice 80 configured to allow gas to exit the auxiliary chamber 15 itself.

[0131] In a preferred, non-limiting embodiment, the pressure control device 25, in particular the gas regulation unit 73, comprises a recovery circuit (only partially shown) configured to at least receive gas from the auxiliary chamber 15, in particular via the outlet orifice 80. In particular, the recovery circuit is also configured to recirculate at least a portion of the gas exiting the auxiliary chamber 15, in particular via the outlet orifice 80. In other words, the recovery circuit is preferentially configured to collect the gas in a controlled manner and also to allow redirecting at least a portion of the gas to the main chamber 14 after reconditioning (i.e., pressurizing, in particular sterilizing) a portion of the gas.

[0132] More specifically, the recovery circuit includes a collection conduit 81 fluidly connected to the auxiliary chamber 15 , particularly via an outlet orifice 80 , for receiving gas from the auxiliary chamber 15 .

[0133] In a preferred, non-limiting embodiment, the exit orifice 80 and / or recovery circuit are configured to allow a constant flow of gas from the auxiliary chamber 15 .

[0134] Advantageously, but not necessarily, the pressure control device 25 also includes a gas inlet assembly 82 configured to control the introduction of fresh gas, particularly originating from the external environment 32, into the gas regulation unit 73. In particular, the inclusion of the gas inlet assembly 82 makes it possible to compensate for possible gas losses from the isolation housing 12 and the gas regulation unit 73, particularly to the external environment 32.

[0135] More specifically, gas inlet assembly 82 is in fluid communication with containment chamber 35 and is configured to draw fresh gas through containment chamber 35 .

[0136] Even more specifically, gas inlet assembly 82 includes an inlet orifice 83 provided in (contained by) containment chamber 35 for permitting at least the inlet of new gas from external environment 32 into containment chamber 35, and also includes a valve member (not shown) for selectively opening and closing the fluid connection between external environment 32 and containment chamber 35, particularly via inlet orifice 83. In particular, gas inlet assembly 82 also includes a through orifice 84 (provided in (contained by) containment chamber 35) and a gas conduction 85 for fluidly connecting confinement chamber 35 and gas regulation unit 73 for conducting gas from confinement chamber 35 to gas regulation unit 73.

[0137] In a preferred, non-limiting embodiment, the valve member is controlled to ensure that the pressure in containment chamber 35 is approximately ambient pressure. Note that gas present in auxiliary chamber 15 may also leak (in an uncontrolled manner) into containment chamber 35 through auxiliary passage 51.

[0138] In a preferred, non-limiting embodiment, the pressure control device 25, particularly the gas regulation unit 73, is configured to draw gas from the sterilizer 7, particularly the shielded chamber 27, and direct it to the gas regulation unit 73 itself, particularly for recirculation.

[0139] Preferably, the pressure control device 25, in particular the gas regulation unit 73, includes a connecting conductor 86 fluidly connected to the sterilization device 7, in particular the shielded chamber 27, and a flow control valve 87 for controlling the flow of gas from the sterilization device 7, in particular the shielded chamber 27, to the gas regulation unit 73.

[0140] In use, the packaging machine 1 forms packaging containers 2 filled with a pourable product.

[0141] More specifically, the method of forming the packaging container 2 includes the following steps: - advancing the web 4 along an advance path P, - folding the web 4 in the main chamber 14 of the isolation housing 12 into a tube 3 at a tube forming station 18; - longitudinally sealing the tube 3 in the main chamber 14; - filling the tube 3 with pourable product; - advancing the tube 3 along a path Q through part of the main chamber 14 and into and through the auxiliary chamber 15; - obtaining single packaging containers 2 from the tubes 3 by forming tubes 3, sealing the tubes 3 transversely between successive packaging containers 2, and in particular cutting the tubes 3 transversely between successive packaging containers 2 to obtain single packaging containers 2.

[0142] Advantageously, the method also includes a step of controlling the pressure, during which the first pressure in the main chamber 14 and the second pressure in the auxiliary chamber 15 are controlled such that the first pressure is higher than the second pressure, and the second pressure is higher than ambient pressure.

[0143] In a preferred, non-limiting embodiment, the method also includes a step of sterilizing at least the first side, and in particular also the second side, of the web 4 at a sterilization station 8. In particular, the sterilization step is carried out before the step of folding the web 4.

[0144] During the step of folding the tube 3, the tube forming and sealing device 16 gradually overlaps the opposing lateral edges of the web 4 to form a longitudinal seal.

[0145] During the step of longitudinally sealing the tube 3, the tube forming and sealing device 16 seals the overlapping opposite lateral edges of the web 4 to obtain a longitudinal seal.

[0146] During the step of advancing the tube 3, the conveying means 5 advances the tube 3 (and the intermediate body of the tube 3) along the path Q to the package forming unit 18.

[0147] In particular, the conveying means 5 advances the tube 3 through part of the main chamber 14 , into and through the auxiliary chamber 15 , and in particular into and through the containment chamber 35 .

[0148] During the step of filling the tubes 3, the filling device 17 fills the longitudinally sealed tubes 3 with the pourable product.

[0149] During the step of obtaining a single packaging container 2, the packaging container forming unit 18 forms a tube 3 between successive packaging containers 2, seals it transversely and preferentially cuts the tube 3 transversely between successive packaging containers 2.

[0150] More specifically, during the step of sterilizing the web 4, at least a substep is carried out in which sterilizing radiation, in particular electromagnetic radiation, and even more particularly electron beam radiation, is directed at least to a first side of the web 4, and preferentially also to a second side.

[0151] More particularly, during the step of controlling the pressure, the first pressure is controlled to be in the range of 200 Pa to 10,000 Pa higher than ambient pressure, preferentially 500 Pa to 9,000 Pa higher than ambient pressure, and even more preferentially 800 Pa to 8,000 Pa higher than ambient pressure.

[0152] In a preferred, non-limiting embodiment 15, during the pressure controlling step, the pressure difference between the first pressure and the second pressure is controlled to be in the range of 500 Pa to 2500 Pa, particularly 800 Pa to 1200 Pa. In particular, the first pressure is controlled to be more than 500 Pa, preferably more than 800 Pa, higher than the ambient pressure.

[0153] More specifically, during the pressure control step, pressurized (sterile) gas is supplied to main chamber 14. In particular, pressurized gas enters main chamber 14 through inlet tube 75.

[0154] In a preferred, non-limiting embodiment, during the pressure controlling step, pressurized (and sterilizing) gas is generated by gas regulation unit 73 .

[0155] Preferably, during the step of controlling the pressure, pressurized gas is supplied from the main chamber 14 to the auxiliary chamber 15 via the flow conducting section 74, and in particular the flow of gas through the flow conducting section 74 is controlled by a control valve 78 for controlling the second pressure.

[0156] In a preferred, non-limiting embodiment, a first pressure within the main chamber 14 is measured and / or determined, particularly to control the control valve 76 .

[0157] In a preferred, non-limiting embodiment, the step of controlling the pressure also includes a sub-step of recirculation, during which gas is extracted from the auxiliary chamber 15 and at least a portion of the extracted gas is reconditioned (pressurized and in particular also sterilized) for fresh injection into the main chamber 14. In particular, during reconditioning, the extracted gas is sterilized and freshly pressurized.

[0158] In a preferred, non-limiting embodiment, the step of controlling the pressure further comprises a sub-step of introducing, during which new gas, in particular coming from the external environment 32, is introduced into the gas regulation unit 73.

[0159] In particular, fresh gas is introduced into the containment chamber 35 via the inlet orifice 83 and directed from the containment chamber 35 to the gas regulation unit 73 via the through orifice 84 and the gas conduction 85 .

[0160] The advantages of the packaging machine 1 according to the invention will be apparent from the foregoing description.

[0161] In particular, the pressure control device 25 controls a first pressure in the main chamber 14 and a second pressure in the auxiliary chamber 15, thereby reducing the mechanical stress on the longitudinal seal while it is still warm and relatively weak.

[0162] Another advantage of the increased stability of the longitudinal seal is the possibility of further increasing the processing speed of the packaging machine 1 .

[0163] A further advantage is that by controlling the pressure in the main chamber 14, it is possible to also control the pressure in the tube 3, thereby further improving control of the overall forming process, particularly at high processing speeds. Because the auxiliary chamber 15 is also pressurized to ambient pressure, the pressure acting on the longitudinal seal is reduced for packaging machines that do not allow the pressure in the auxiliary chamber to be greater than ambient.

[0164] A still further advantage is the improved stability of the tube 3 with respect to the stability of tubes in state-of-the-art packaging machines 1 .

[0165] Obviously, modifications may be made to the packaging machine 1 described herein without departing from the scope of protection defined in the appended claims.

[0166] In an alternative embodiment not shown, the primary seal assembly 43 may be floatingly coupled to the primary separation wall 41. In such an alternative configuration, the primary seal assembly 43 may have a design similar to that of the secondary seal assembly 52. Preferably, in such an alternative embodiment, the engagement surfaces 47 may also be formed to allow movement of the respective carrier structures 45 along a direction transverse to the axis A.

Claims

1. 1. A packaging machine (1) for producing sealed packages (2) of pourable products from a web (4) of packaging material advancing along a web advancement path (P), comprising: - conveying means (5) for advancing said web (4) of packaging material along said web advancement path (P) to at least a tube forming station (6) where said web (4) of packaging material is formed into a tube (3) in use, and for advancing said tube (3) along a tube advancement path (Q); an isolation housing (12) having a main chamber (14) and an auxiliary chamber (15) located downstream of said main chamber (14) along said tube advance path (Q); a tube forming and sealing device (16) located at least partially within said main chamber (14) and configured, in use, to form and longitudinally seal said tube (3) within said main chamber (14); a filling device (17) for filling said tube (3) with said pourable product; a pressure control device (25) configured to control a first pressure in the main chamber (14) and a second pressure in the auxiliary chamber (15) such that the first pressure is greater than the second pressure, and the first pressure and the second pressure are both greater than ambient pressure; A packaging machine (1) comprising:

2. 2. The packaging machine of claim 1, wherein the pressure control device (25) is configured to control the first pressure to be in the range of 200 Pa to 10,000 Pa higher than ambient pressure.

3. 3. The packaging machine according to claim 1, wherein the pressure control device (25) is configured to control the first pressure and the second pressure so that a pressure difference between the first pressure and the second pressure is in a range of 500 Pa to 2500 Pa.

4. The pressure control device (25) a gas regulation unit (73) for introducing pressurized gas into said main chamber (14) to control said first pressure; a flow conductor (74) fluidly connecting the main chamber (14) with the auxiliary chamber (15) and configured to allow gas flow from the main chamber (14) to the auxiliary chamber (15); The packaging machine according to any one of claims 1 to 3, comprising:

5. 5. The packaging machine of claim 4, further comprising a valve (78) disposed in the flow conducting portion (74), the valve (78) configured to control the flow of the gas through the flow conducting portion (74) from the main chamber (14) to the auxiliary chamber (15) to control the second pressure.

6. 6. The packaging machine according to claim 1, wherein the pressure control device (25) comprises a measuring unit (79) configured to measure and / or determine the first pressure in the main chamber (14).

7. the isolation housing (12) includes at least one main passage (42) for allowing passage of the tube (3) from the main chamber (14) to the auxiliary chamber (15) during use; A packaging machine according to any one of the preceding claims, wherein the packaging machine (1) further comprises at least one main seal assembly (43) configured to seal the main passageway (42) in use.

8. The isolation housing (12) further comprises at least one auxiliary passage (51) for allowing passage of the tube (3) out of the auxiliary chamber (15); 8. The packaging machine of claim 7, wherein the packaging machine (1) further comprises at least an auxiliary seal assembly (52) configured to seal the auxiliary passage (51) in use.

9. The isolation housing (12) extends along a longitudinal axis (A); 9. The packaging machine of claim 8, wherein at least a portion of the auxiliary seal assembly (52) is configured to move in a plane (H1) transverse to the longitudinal axis (A) as a result of interaction with the advancing tube (3) during use.

10. 10. The packaging machine of any one of claims 1 to 9, wherein the pressure control device comprises a recovery circuit having a collection conductor (81) connected to the auxiliary chamber (15), the recovery circuit being configured to receive gas from the auxiliary chamber (15) and recirculate at least a portion of the gas back to the main chamber (14), in particular after reconditioning of the portion of the gas.

11. 11. The packaging machine of claim 1, wherein the isolation housing (12) comprises a containment chamber (35) arranged downstream of the auxiliary chamber (15) along the tube advancement path (Q) and adapted to receive gas leaking from the auxiliary chamber (15).

12. A method for producing a sealed package (2) of a pourable product, comprising: - advancing the web of packaging material (4) along a web advancement path (P) at least to a tube forming station (6); - folding said web of packaging material (4) in the main chamber (14) of the isolation housing (12) into a tube (3) at said tube forming station (6); - longitudinally sealing said tube (3) in said main chamber (14); - advancing said tube (3) along a tube advancement path (Q) through a part of said main chamber (14) and into and through an auxiliary chamber (15) of said isolation housing (12) arranged downstream of said main chamber (14) along said tube advancement path (Q); - filling said formed tube (3) with said pourable product; - controlling a pressure, wherein the first pressure is controlled in the main chamber (14) and the second pressure is controlled in the auxiliary chamber (15) such that during the step of controlling the pressure, the first pressure is higher than the second pressure and the second pressure is higher than the ambient pressure; A method comprising:

13. 13. The method of claim 12, wherein during the step of controlling the pressure, the first pressure is controlled to be in a range of 200 Pa to 10,000 Pa above ambient pressure.

14. 14. The method according to claim 12 or 13, wherein during the step of controlling the pressure, the first pressure is controlled to be at least 500 Pa higher than ambient pressure, and a pressure difference between the first pressure and the second pressure is controlled to be in the range of 500 Pa to 2500 Pa.

15. 15. The method according to claim 12, wherein during the step of controlling the pressure, pressurized gas is supplied to the main chamber (14) and the pressurized gas is supplied from the main chamber (14) to the auxiliary chamber (15) through a flow conducting section (74), the flow of gas through the flow conducting section (74) being controlled by a control valve (78) arranged at least in the flow conducting section (74).

16. The filling device (17) comprises a filling tube (66) partially disposed within the tube (3) for supplying the pourable product to the tube (3); The filling tube (66) extends outside the isolation housing (12) and supplies the pourable product to the tube (3) outside the isolation housing (12). The packaging machine according to claim 1.

17. The apparatus further comprises a packaging container forming unit (18) for sealing the tube laterally, cutting the tube laterally, and forming a packaging container; The package forming unit (18) is arranged below the isolation chamber (18), the filling tube (66) extends into the main chamber (14), the auxiliary chamber (15) and the package-forming unit (18) and supplies the pourable product to the tube (3) within the package-forming unit (18); 17. The packaging machine of claim 16.

18. The step of filling with the pourable product comprises supplying the pourable product to the formed tube outside the isolation housing (12). The method of claim 12.

19. The method according to claim 1, further comprising the steps of transversely sealing and transversely cutting the pourable product-filled tube.

20. The method of claim 18.

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