EP4650285A2

EP4650285A2 - Nozzle unit, sterilizing agent removal assembly for a sterilization unit and packaging machine configured for the production of sealed packages containing a pourable product

Info

Publication number: EP4650285A2
Application number: EP25156991.9A
Authority: EP
Inventors: PierPaolo Algeri
Original assignee: Tetra Laval Holdings and Finance SA
Current assignee: Tetra Laval Holdings and Finance SA
Priority date: 2024-03-08
Filing date: 2025-02-11
Publication date: 2025-11-19
Also published as: WO2025185932A1; WO2025185932A8

Abstract

There is described a nozzle unit (22) configured to direct a flow of gas towards a side of a web (3) of packaging material designed to produce sealed packages (2) containing a pourable product, wherein the nozzle unit (22) comprises a nozzle frame (26) and a nozzle member (27) having a nozzle surface (23) provided with openings through which supplying the flow of gas and the nozzle frame (26) and the nozzle member (27) are connectable to one another in a releasable manner. The nozzle unit (22) further comprises a locking and unlocking device (30) with at least a bracket (32) being elastically deformable metallic and provided with a rear portion (35) connected to a first surface (34) of the nozzle frame (26) and a front portion (36) configured to define a seat which accommodates an end portion of the nozzle member (27) .

Description

TECHNICAL FIELD

The present invention relates to nozzle unit, to a sterilizing agent removal assembly for a sterilization unit and to a packaging machine configured for the production of sealed packages containing a pourable product.

BACKGROUND ART

As it is generally known, many pourable food products, such as fruit juice, UHT (ultra-high temperature-treated) milk, wine, tomato sauce, etc., are sold in packages made of sterilized packaging material. A typical example is the parallelepiped-shaped package for pourable food products known as Tetra Brik Aseptic (registered trademark), which is made by folding and sealing a laminated web of packaging material.
The packaging material has a multilayer structure comprising a base layer, e.g. made 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, 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 apparatuses, which form and fill the packages starting from a multilayer web of packaging material.
In particular, a continuous tube is formed from the web of packaging material which is initially wound in a reel and fed through a plurality of unwinding rollers. The web of packaging material is typically sterilized in the packaging apparatus, e.g. by applying a chemical sterilizing agent, such as hydrogen peroxide solution, which, once sterilization is completed, is removed from the surfaces of the packaging material, e.g. evaporated by heating. The web so sterilized is then maintained in a closed, sterile environment, and, while advanced by the aforementioned unwinding rollers, is folded to form the tube by means of a known web folding unit and then sealed longitudinally.
In order to perform the package forming operations, the tube is continuously fed along a first direction, normally a straight vertical direction, is filled with the sterilized food product from above and is formed, sealed and subsequently cut along equally spaced transversal cross-sections extending along a second direction, normally a direction orthogonal to the first direction.
In detail, a typical packaging apparatus comprises a plurality of forming, sealing and cutting assemblies, each one advanced along an operative path parallel to the first direction. During such advancement, the forming, sealing and cutting assemblies start interacting with the tube at preset positions along the operative path and follow the tube advancing along the first direction so as to shape, to transversally seal and to cut the tube so as to obtain single pillow packs.
In greater detail, the known packaging apparatuses comprise a forming and sealing unit configured to form the tube, so as to imprint an external shape to it, corresponding to the desired shape of the package, and to seal the tube at equally spaced cross-sections orthogonal to the tube advancement direction. So-called pillow packs are obtained thereby, which have a longitudinal sealing band, a top transversal sealing band and a bottom transversal sealing band. The pillow packs are then cut at the cross-sections to be separated from one another and directed to a folding unit of the packaging machine for the final folding thereof, in order to obtain the finished packages.
As said, the web of packaging material must be sterilized before being folded into the tube. Accordingly, a typical packaging apparatus comprises a sterilization unit arranged upstream of the web folding unit and configured to apply a chemical sterilizing agent, usually containing a hydrogen peroxide solution.
After the application and the sterilization, the sterilizing agent must be removed from the web. To this end, the sterilization unit typically comprises a pair of squeezing rollers, and in particular a roller and a counter-roller, arranged in rotational abutment against one another and configured to receive the advancing web therebetween. By advancing the web in between the squeezing rollers, the sterilizing agent is substantially squeezed off the web itself. In some cases, possible residues of sterilizing agent are fully dried out and/or removed by a blowing device arranged downstream of the squeezing rollers and configured to blow a jet of gas (usually sterilized air) towards the web.
Normally, besides the squeezing rollers and the blowing device, the sterilization agent removal assembly comprises a pair of nozzle devices, in particular a first nozzle device and a second nozzle device arranged at opposite sides of the advancing web, facing one another, and configured to blow air towards a respective side of the web. In particular, the first nozzle device is configured to direct a flow of air towards an inner side of the web adapted to define the inner wall of the packages, whereas the second nozzle device is configured to direct a flow of air towards an outer side of the web adapted to define the outer wall of the packages.
More specifically, each nozzle device has a respective blowing wall, arranged facing the blowing wall of the other nozzle device, with the interposition in use of the advancing web, and provided with a series of shaped ports or openings through which the flow of air is supplied towards the respective side of the web. Typically, each nozzle device comprises a nozzle frame and a nozzle member coupled to one another in a removable (or releasable) manner. More in detail, the nozzle frame comprises a housing fluidically connected to the blowing device, and the nozzle member is provided with the blowing wall. To avoid undesired deposits of the sterilizing agent, the nozzle member is periodically (daily) disengaged from the nozzle frame to be maintained and cleaned.
Even though the known sterilization agent removal assemblies provide good results and works satisfactorily well, a need is felt within the industry to further improve the operation.

DISCLOSURE OF INVENTION

It is therefore an object of the present invention to provide gas nozzle unit addressing the drawbacks of the prior art and, in particular, being easy to be disassembled for cleaning.
A further object of the present invention is to provide a sterilizing agent removal assembly for a sterilization unit addressing the drawbacks of the prior art and, in particular, being easy to be disassembled for cleaning.
A further object of the present invention is to provide a packaging machine configured for the production of sealed packages containing a pourable product addressing the drawbacks of the prior art and, in particular, being easy to be disassembled for cleaning.
According to the invention there are a gas nozzle unit, a sterilizing agent removal assembly for a sterilization unit and a packaging machine configured for the production of sealed packages containing a pourable product according to the appended claims.

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 perspective view, with parts removed for clarity, of a packaging machine including a sterilization unit equipped with a sterilizing agent removal assembly according to the present disclosure;
figure 2 is a schematic side view of the packaging machine of figure 1;
figure 3 is a perspective view, with parts removed for clarity, of a nozzle unit in an unlocked position according to the present disclosure in the sterilization unit of figure 1;
figures 4 and 5 are perspective views, with parts removed for clarity, of the nozzle unit of figure 3 in respective intermediate positions between the unlocked position and a locking position;
figure 6 is a perspective view, with parts removed for clarity, of the nozzle unit of figure 3 in the locking position;
figure 7 is a plan and enlarged view if a detail of the nozzle unit of figures from 3 to 6.

BEST MODE FOR CARRYING OUT THE INVENTION

Number 1 indicates as a whole a packaging machine for producing sealed packages 2 of a pourable 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. In more detail, packaging machine 1 may be configured to produce packages 2 from a multilayer packaging material, preferentially, a multilayer packaging material 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 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 these 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 the 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.
In further detail, the multilayer packaging material may be provided in the form of a web 3.
According to a possible embodiment (not shown), the web 3 of packaging material is provided with a longitudinal sequence of closure structures pre-applied thereon.
Furthermore, packaging machine 1 is configured to produce packages 2 by forming a tube 4 from the web 3, longitudinally sealing the tube 4, filling the tube 4 with the pourable product and to transversally seal, and preferentially transversally cut the tube 4.
According to some possible non-limiting embodiments, each package 2 extends along a longitudinal axis and comprises at least a first transversal sealing band 5, and preferentially also a second transversal sealing band arranged at opposite ends of the package 2.
Moreover, each package 2 also comprises a longitudinal seam portion 6. Preferentially, each first transversal sealing band 5 and/or each second transversal sealing band are transversal (preferentially perpendicular) to the respective longitudinal seam portion 6.
Packaging machine 1 comprises a package forming apparatus configured to at least partially form the tube 4, preferentially to also transversally seal and/or to transversally cut the tube 4, for obtaining the packages 2.
With particular reference to figures 1 and 2, the packaging machine 1 comprises:

a conveying device 8 configured to advance along a conveying path P the web 3 and the tube 4; and/or
a tube forming and sealing device 9 configured to form the tube 4 from the advancing web 3 and to longitudinally seal the tube 4; and/or
a filling device 10 for filling the tube 4 with the pourable product.

The packaging machine 1 further comprises a package forming apparatus (not shown) configured to transversally seal and/or to transversally cut the tube 4, for obtaining the packages 2.
In further detail, the packaging machine 1 comprises an isolation chamber 11, preferentially delimiting an inner environment 12 from an outer environment. Preferentially, the inner environment 12 is a sterile (aseptic) environment, preferably containing a controlled atmosphere. Preferentially, the tube forming and sealing device 9 is at least partially arranged within the isolation chamber 11, in particular within the inner environment 12, and is configured to fold and longitudinally seal the tube 4 within the isolation chamber 11, in particular within the inner environment 12.
The tube forming and sealing device 9 comprises at least two forming assemblies 13, 14 preferentially arranged within the isolation chamber 11, even more preferentially arranged within the inner environment 12, configured to gradually fold in cooperation with one another the web 3 of packaging material into the tube 4, preferentially by overlapping opposite longitudinal edges of the web 3 of packaging material with one another. Thereby, in use, the seam portion 6 is formed. The forming assemblies 13, 14 are spaced apart from, and parallel to, one another. Furthermore, the forming assemblies 13, 14 are arranged coaxial to one another. In particular, the tube forming and sealing device 9 comprises the forming assembly 13 and the forming assembly 14 placed along the conveying path P in succession (one after the other) carried by a fixed structure and interacting with the web 3 of packaging material.
Additionally, the tube forming and sealing device 9 comprises a sealing device 18 having a sealing head 19, preferentially arranged within the isolation chamber 11, even more preferentially within the inner environment 12, and configured to longitudinally seal the tube 4, preferentially along the longitudinal seam portion 6.
More specifically, the sealing head 19 is configured to transfer thermal energy to the tube 4, in particular to the longitudinal seam portion 6 for longitudinally sealing the tube 4. The sealing head 19 can be of the kind operating by means of induction heating and/or by a stream of a heated gas and/or by means of ultrasound and/or by laser heating and/or by any other means.
Preferentially, the filling device 10 comprises a filling pipe 20 configured to direct the pourable product into the tube 4. Preferentially, the filling pipe 20 is at least partially placed within the tube 4 for continuously feeding, in use, the pourable product into the tube 4.
Moreover, as shown in figure 2, the packaging machine 1 comprises a sterilization unit 15 configured to sterilize the advancing web 3 of packaging material. Preferentially the sterilization unit 15 is arranged upstream of the tube forming and sealing device 9 along the conveying path P. The web 3 of packaging material is fed along the conveying path P by means of guiding elements 16, in particular by a number of rollers 16. The sterilization unit 15 has a sterilizing bath, in which a chemical sterilizing agent is applied to the web 3 of packaging material. Advantageously, the chemical sterilizing agent comprises a hydrogen peroxide solution.
The sterilization unit 15 comprises a sterilizing agent removal assembly 17 which is configured to remove the sterilizing agent from the web 3 of packaging material.
The sterilizing agent removal assembly 17 comprises a blower 21 configured for supplying a flow of gas. Preferably, the blower 21 is configured for supplying a flow of sterile air withdrawn from the isolation chamber 11. The sterilizing agent removal assembly 17 comprises a couple of nozzle units 22 arranged facing one another, defining between one another a treatment zone for the web 3 of packaging material to advance therethrough and configured to receive the flow of gas and to blow the gas towards a respective side of the web 3 of packaging material. Both the nozzle units 22 are fluidically connected to the blower 21 through a respective duct 25. In light of the above, the treatment zone is defined as the region of space comprised between, and laterally delimited by, the two nozzle units 22.
The nozzle unit 22 is configured to direct the flow of gas towards a respective side of the web 3 of packaging material and is provided with a nozzle surface 23 having a number of openings 24 through which supplying the flow of gas. Thus, the treatment zone is comprised between, and laterally delimited by the two nozzle surfaces 23.
Advantageously, the nozzle surface 23 has a number of openings 24 shaped as elongated slits and/or substantially circular holes. In particular, the nozzle surface 23 is provided with a plurality (or a group) of openings 24.
According to figure 3, the nozzle surface 23 is provided with two groups of openings 24, wherein the openings 24 of each group are aligned one next to the other. The two groups of openings 24 are arranged parallel and spaced apart from one another.
The nozzle unit 22 comprises a nozzle frame 26 and a nozzle member 27 coupled to the nozzle frame 26. More in detail, the nozzle member 27 is connected to the nozzle frame 26 in a removable (or releasable) manner. The nozzle frame 26 comprises a housing 28. The housing 28 is preferably box-shaped and realized in a metallic material. The housing 28 is provided with a rear collar element 29 configured for the fluidically connection to the duct 25.
The nozzle member 27 is provided with the nozzle surface 23. According to a preferred embodiment, the nozzle member 27 is provided with a rear surface 31 having a profile configured to be coupled, preferably without interference, to the housing 28. In particular, the rear surface 31 has a shape complementary with a shape of the housing 28. According to an embodiment, the rear surface 31 is substantially flat and is configured to abut against the housing 28.
The nozzle unit 22 further comprises a locking and unlocking device 30 configured for coupling (i.e. locking) the nozzle member 27 to the nozzle frame 26 and releasing (i.e. unlocking or uncoupling) the nozzle member 27 from the nozzle frame 26 from.
The locking and unlocking device 30 comprises a number of brackets 32. The brackets 32 are firmly connected to the nozzle frame 26 (in particular, to the housing 28). Preferably, the brackets 32 are connected through fixing means 33 (for example, screws) to a first surface 34 of the nozzle frame 26 (in particular, of the housing 28). Preferably, the first surface 34 is a lower/inferior surface 34 of the nozzle frame 26 (in particular, of the housing 28). Advantageously, the locking and unlocking device 30 comprises a plurality of brackets 32. Preferably, the locking and unlocking device 30 comprises two brackets 32 arranged parallel to one another and at a predetermined distance from each other. The two brackets 32 are arranged at respective ends (sides) of the first surface 34.
The brackets 32 are elastically deformable metallic. In other words, the brackets 32 are configured to recover its original shape when released after being loaded/distorted.
Each bracket 32 comprises a rear portion 35 configured to be arranged in contact with the first surface 34 and connected thereto by the fixing means 33.
Each bracket 32 further comprises a front portion 36 configured to accommodate the nozzle member 27. More in detail, the front portion 36 is shaped so as to define a seat which accommodates an end portion of the nozzle member 27. In particular, the front portion 36 has a substantially U-shape. The U-shape allows the bracket 32 to be elastically deformable. Preferably, the brackets are in stainless steel.
The front portion 36 of each bracket 32 projects from the nozzle frame 26 towards the nozzle member 27. In such a way, said seat for the nozzle member 27 is defined between an end portion of the front portion 36 and the nozzle frame 26 (in particular, a surface of the housing 28 facing the nozzle member 27). It should be noted that the nozzle member 27 is accommodated in said seat, with the nozzle frame 26 being in a locked position. The nozzle member 27 is removed from said seat, with nozzle member 27 being in an unlocked position with respect to the nozzle frame 26.
The locking and unlocking device 30 further comprises a coupling device 37. The coupling device 37 is preferably connected in a fixed and not releasable manner to the nozzle member 27. Preferably, the coupling device 37 is connected to a second surface 50 of the nozzle member 27. The second surface 50 is opposite to the portion of the nozzle member 27 which is accommodatable in said seat defined by the brackets 32. Advantageously, the coupling device 37 is connected to the second surface 50 in a position intermediate between the two brackets 32 (in particular, approximately halfway). In other words, the coupling device 37 is connected approximately at an intermediate point of the second surface 50.
The coupling device 37 (or at least a portion thereof) is elastically deformable. In other words, the coupling device 37 is configured to recover its original shape when released after being loaded/distorted.
The coupling device 37 is rotatable around an axis X. Advantageously, the coupling device 37 is rotatable from and to a locking position in which the nozzle member 27 is fixed to the nozzle frame 26. More in detail, the coupling device 37 is rotatable around the axis X from an unlocked position in which the nozzle member 37 is unfixed from the nozzle frame 26 to the locking position in which the nozzle member 37 is fixed to the nozzle frame 26, and vice versa.
Advantageously, the coupling device 37 comprises a lever element 38, having a substantially L shape, and configured to be operated by an operator and rotated around the axis X.
With reference to figure 7, the coupling device 37 further comprises a locking element 39 having an inferior surface arranged in contact with the second surface 50 and configured to slide on a third surface 51 of the housing 28 (opposite to the first surface 34) for coupling and uncoupling the nozzle frame 26 to the nozzle member 27. More in detail, the locking element 39 is configured for coupling to and uncoupling from a pin 40, having a cylindrical shape and protruding upwards from the third surface 51.
In particular, the locking element 39 is the portion of the coupling device 37 which is elastically deformable metallic. In other words, the locking element 39 is configured to recover its original shape when released after being loaded/distorted.
The locking element 39 comprises a U-shaped hook element 41 and a coupling appendix 42. The U-shaped hook element 41 is connected at one end to the lever element 38 and to the other end to the coupling appendix 42. The U-shape of the hook element 41 allows the locking element 39 (in particular, the hook element 41) to be elastically deformable. Preferably, the locking element 39 is in stainless steel.
The coupling appendix 42 defines a cavity 43 of substantial semicircular shape and configured for being arranged in contact with the pin 40. Advantageously, the cavity 43 has a shape complementary to the shape of the pin 40. More in detail, the coupling appendix 42 comprises an internal portion 44 provided with a protruding rib 45.
The coupling appendix 42 further comprises a portion 46 which is connected to the hook element 41, at a first end, and has a variable thickness so as to define a tooth element 47, at a second end. Tooth element 47 has a slanted shape 52. During rotation around the axis X, the tooth element 47 gets in contact with the pin 40 and as long as the rotation continues the slanted shape 52 makes the U-shaped hook element 41 to be elastically deformed until the cavity 43 will be in contact with (i.e. embraces) the pin 40. As a result, the hook element 41 is deformed before the cavity 43 being arranged in contact with the pin 40.
Finally, the locking element 39 comprises a portion 48 arranged within the cavity defined by the U-shaped hook element 41. The portion 48 protrudes from a connection point of lever element 38 with locking element 39, towards the coupling appendix 42. In particular, the portion 48 is interposed between the U-shaped hook element 41 and the internal portion 44. The portion 48 defines a U-shaped cavity 49 facing the internal portion 44. In use, the rib 45 is positioned within the U-shaped cavity 49. In particular, the coupling assembly 42 has an L-shape, defined by said internal portion 44 and said protruding rib 45 which projects from said internal portion 44 towards said portion 48.
The locking element 39 is configured to rotate around the axis X to be arranged in the locking position, wherein the cavity 43 surrounds in contact the pin 40 and the tooth element 47 blocks the coupling device 37 onto the pin 40.
Advantageously, the assembly defined by the lever element 38 and the locking element 39 (and its coupling appendix 42) are a single body. In other words, the lever element 38 and the locking element 39 are solid to each other thereby a rotation of the lever element 38 causes a rotation of the locking element 39 (and of its coupling appendix 42).
In use, the rib 45 is positioned within the U-shaped cavity 49 without touching the portion 48. In other words, there should not be any contact between the rib 45 and the portion 48 while cavity 43 engages pin 40. Hence, in normal use, if the second surface 50 of the nozzle member 27 is correctly engaged with the nozzle frame 26, the cavity 43 engages the pin 40 without any contact between the rib 45 and the portion 48.
Conversely, if the second surface 50 of the nozzle member 27 is not correctly engaged with the nozzle frame 26 (i.e. an undesired interspace is present) and, despite of such incorrect engagement, the operator tightens the lever element 38, the rib 45 moves till contacting the portion 48 such that the U-shaped cavity 49 defines a limit stop for the movement of the rib 45. In such a way, the U-shaped cavity 49 avoids that the hook element 41 (in particular a central portion thereof) reaches the yield point.
The locking element 39 is designed to have a limited deformation during the rotation around axis X to the locking position. In this way, wrong assemblies of the nozzle member 27 to the nozzle frame 26 and undesired damages to the coupling device 37 are avoided.
The method for assembling the nozzle unit 22 (i.e. for assembling the nozzle member 27 to the nozzle frame 26) comprises the following steps of:

inserting the end portion of the nozzle member 27 within the seats defined in the front portions 36 of the two brackets 32 (figure 3);
pushing the nozzle member 27 against the nozzle frame 26, in particular against the housing 28, thereby elastically deforming and loading the brackets 32; advantageously the rear surface 31 is coupled, preferably without interference, to the housing 28 or is abutted against the housing 28 (figure 4);
rotating the coupling device 37 around the axis X to the locking position in which the cavity 43 surrounds in contact the pin 40 and the tooth element 47 overcomes the pin 40 and the coupling device 37 is blocked in the locking position (figures 5 and 6).

Advantageously, for disassembling the nozzle member 27 from the nozzle frame 26, an operator must intervene on the lever element 38 by disengaging the tooth element 47 from the pin 40; the coupling device 37 is then rotated around the axis X from the locking position such that the cavity 43 is not arranged in contact with the pin 40. Finally, the end portion of the nozzle member 27 is removed from the seats defined in the front portions 36 of the two brackets 32.
The nozzle unit 22 realized according to the present invention has some advantages thar result clear from the foregoing description. In particular, the nozzle unit 22 is easy to be disassembled for cleaning and allows to direct the maximum flow of gas (air) towards the web 3 of packaging material avoiding gas leakages. More specifically, the nozzle member 27 and the nozzle frame 26 are easy to be disengaged from one another and re-engaged after the cleaning ana maintenance operation. In particular, the locking and unlocking device 30 is designed such that, in the locking position, the nozzle member 27 and nozzle frame 26 are kept in contact with a predetermined load avoiding side gas leakages. Moreover, the coupling device 37 is designed to have a limited deformation during the rotation around axis X to the locking position and thereby wrong assemblies of the nozzle member 27 to the nozzle frame 26 and undesired damages to the coupling device 37 are avoided. Finally, the coupling between the profile of the rear surface 31 and the housing 28 defines a labyrinth path for the gas which makes it very difficult any side gas leakage.

Claims

A nozzle unit (22) configured to direct a flow of gas towards a side of a web (3) of packaging material designed to produce sealed packages (2) containing a pourable product, wherein the nozzle unit (22) comprises:
- a nozzle frame (26);

- a nozzle member (27) having a nozzle surface (23) provided with openings through which supplying the flow of gas; wherein the nozzle frame (26) and the nozzle member (27) are connectable to one another in a releasable manner;

- a locking and unlocking device (30) configured for lock and unlock the nozzle frame (26) to and from the nozzle member (27), wherein the locking and unlocking device (30) comprises at least one bracket (32) having:

- a rear portion (35) connected to a first surface (34) of the nozzle frame (26); and

- a front portion (36) configured to define a seat which accommodates an end portion of the nozzle member (27),
wherein said at least one bracket (32) is, at least in part, elastically deformable.
A nozzle unit (22) according to claim 1, wherein the front portion (36) of said at least one bracket (32) is elastically deformable.
A nozzle unit (22) according to claim 1 or 2, comprising at least a pair of brackets (32) arranged parallel to one another and at a predetermined distance from one another, wherein said at least a pair of brackets (32) defines said at least one bracket (32).
A nozzle unit (22) according to any one of the previous claims, wherein said front portion (36) has a substantially U-shape and projects from the nozzle frame (26) towards the nozzle member (27).
A nozzle unit (22) according to any one of the previous claims and comprising a coupling device (37) connected to the nozzle member (27), at a second end thereof, opposite to said end.
A nozzle unit (22) according to claim 5, wherein the coupling device (37) is connected approximately halfway to the second surface (50).
A nozzle unit (22) according to claim 6, wherein the coupling device (37) is at least partially elastically deformable.
A nozzle unit (22) according to claim 6 or 7, wherein the coupling device (37) is rotatable around an axis (X) from an unlocked position in which the nozzle member (27) is unfixed from the nozzle frame (26) to a locking position in which the nozzle member (27) is fixed to the nozzle frame (26).
A nozzle unit (22) according to claim 8, wherein the coupling device (37) comprises a lever element (38) configured to be operated by an operator and rotated around the axis (X).
A nozzle unit according to any claim from 6 to 9, wherein the nozzle frame (26) is provided with a third surface (51) having a pin (40) protruding therefrom; and wherein the coupling device (37) is configured for being coupled to and uncoupled from the pin (40), wherein the coupling device (37) comprises a locking element (39) connected to the lever element (38) and having a surface configured to slide on the third surface (51) .
A nozzle unit (22) according to claim 10, wherein the locking element (39) comprises an appendix (42) defining a cavity (43) having a shape complementary to the shape of the pin (40) and configured for engaging the pin (40).
A nozzle unit (22) according to claim 11, wherein the appendix (42) comprises a first portion (46) having a variable thickness so as to define a tooth element (47) configured to block the coupling device (37) onto the pin (40) .
A nozzle unit according to any claim 10 to 12, wherein the locking element (39) is elastically deformable.
A nozzle unit according to any claims 11 to 13, wherein the locking element (39) further comprises a portion (48) defining a respective U-shaped cavity (49), and the appendix (42) comprises an internal portion (44) provided with a protruding rib (45) being configured to be positioned within the U-shaped cavity (49) of the portion (48), wherein the portion (48) is configured such that there is no contact between the protruding rib (45) and the U-shaped cavity (49) of portion (48) while the cavity (43) of the appendix (42) engages the pin (40) of nozzle frame (26).
A sterilizing agent removal assembly (17) for a sterilizing unit (15) of a packaging machine (1) configured to produce sealed packages containing a pourable product from a web (3) of packaging material comprising:
- a blower (21) for supplying a flow of gas;

- at least a first nozzle unit (22) according to any one of the previous claims.
A packaging machine (1) configured for producing sealed packages (2) containing a pourable product starting from a web (3) of packaging material comprising:
- a conveying device (8) configured to advance the web (3) of packaging material along a conveying path (P);

- a sterilization unit (15) for applying a sterilizing agent on the web (3) of packaging material comprising a sterilizing agent removal assembly (17) according to claim 14 and configured to remove the sterilizing agent from the web (3) of packaging material;

- a tube forming and sealing device (9) arranged downstream of the sterilization unit (15) along the conveying path (P) and configured for folding the web (3) of packaging material into a tube (4) and longitudinally sealing the tube (4).