WO2025247662A1 - Cleaning unit for a packaging machine configured to produce sealed packages containing a pourable product - Google Patents

Abstract

There is described a cleaning unit (8) for a packaging machine (1) configured to produce sealed packages (2) containing a pourable product, the cleaning unit (8) being configured to clean at least one component (12) of the packaging machine (1), the cleaning unit (8) comprising a housing (15) internally defining a cleaning chamber (16) adapted to receive a cleaning medium and the component (12), or part of the component (12), to be cleaned; the cleaning unit (8) includes a shaped profile (19) within the housing (15), the shaped profile (19) being configured to guide the cleaning medium within the cleaning chamber (16) so as to follow an external surface (12a) of said component (12) or part of the component (12).

Description

CLEANING UNIT FOR A PACKAGING MACHINE CONFIGURED TO

PRODUCE SEALED PACKAGES CONTAINING A POURABLE PRODUCT

TECHNICAL FIELD

The present invention relates to a cleaning unit for a packaging machine configured to produce sealed packages containing a pourable product, whereby the cleaning unit is configured for cleaning one or more components of such packaging machine.

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 heatseal plastic material , and is in turn covered with another layer of heat-seal plastic material forming the inner face of the package eventually contacting the food product .

Packages of this sort are normally produced on fully automatic packaging machines , which form and fill the packages starting from a multilayer web of packaging material .

In particular, the web of packaging material is initially wound in a reel and fed through a plurality of unwinding rollers .

The web of packaging material is typically maintained in a closed, sterile environment , and, while advanced by the aforementioned unwinding rollers , is folded to form a continuous tube by means of a known web folding device . The tube is then sealed longitudinally .

In order to perform the package forming operations , the tube is continuously fed along a straight vertical direction, is filled from above with the sterili zed food product and is formed, sealed and subsequently cut along equally spaced transversal cross-sections extending along a direction orthogonal to the vertical 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 .

The finished packages are thereby obtained .

In order to fill the tube with the pourable product , the packaging machine typically comprises a filling system configured to fill the tube with the pourable product , while the tube is continuously formed, sealed and advanced .

In detail , the filling system comprises a filling pipe which is inserted in, and surrounded by, the tube in formation and which delivers the pourable product into the tube .

The filling pipe is typically divided into an upper duct , fluidly connected to a pourable product source ( e . g . a tank or reservoir ) , and a lower duct , which is fluidly connected to the upper duct and opens into the tube for delivering the product therein .

Usually, the filling system further comprises a floating element fitted to the lower duct , preferably at a lower end portion thereof , configured to measure the filling level of the tube , according to a manner known .

As it is known, various components of the packaging machine need to undergo a cleaning process . In particular, the components of the filling system need to undergo a periodic cleaning process , in order to meet the hygiene requirements and/or to prevent residues of a first pourable product used during a production cycle from contaminating the packages filled with a second pourable product during a successive production cycle .

To this end, the packaging machines usually comprise a cleaning unit for automatically cleaning the aforementioned components .

Although the known cleaning units operate satis fyingly wel l , the Applicant has observed that they are still open to further improvement , in particular as per the ef fectiveness of the cleaning process .

DISCLOSURE OF INVENTION

It is therefore an obj ect of the present invention to provide a cleaning unit which is designed to meet the above-mentioned need in a straightforward and low-cost manner .

This obj ect is achieved by a cleaning unit as claimed in the appended independent claim 1 . Preferred embodiments of the present invention are laid down in the appended dependent 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 cleaning unit according to the present invention;

Figure 2 is a larger-scale , partially sectioned perspective view, with parts removed for clarity, of the cleaning unit of Figure 1 ; and

Figures 3 and 4 are perspective view, with parts removed for clarity, of part of the cleaning unit of Figure 2 during two distinct operative configurations .

BEST MODE FOR CARRYING OUT THE INVENTION

With reference to Figure 1 , number 1 indicates as a whole a non-limiting example of a packaging machine configured for producing sealed packages 2 containing a pourable product , preferably a pourable food product such as pasteuri zed or UHT milk, water, fruit j uice , wine , peas , beans , etc .

In detail , packaging machine 1 is configured to form, seal and fold packages 2 starting from a web 4 of packaging material , which is initially wound in a reel 40 , and then folded into a tube 3 of packaging material , according to a manner known and not described in detail .

Preferably, the packaging material has a multilayer structure (not shown) , and comprises a layer of fibrous material , e . g . paper, covered on both sides with respective layers of heat-seal plastic material , e . g . polyethylene .

In the case of aseptic packages 2 for long-storage products , such as UHT milk, the packaging material also comprises a layer of gas-and-light barrier material , e . g . aluminum foil or ethylene vinyl alcohol (EVOH) film, which is superimposed on a layer of heat-seal plastic material , and is in turn covered with another layer of heat-seal plastic material , the latter forming the inner face of package 2 eventually contacting the pourable product .

As schematically shown in Figure 1 , packaging machine 1 comprises conveying means configured to advance the web 4 along an advancement path .

Packaging machine 1 comprises a web folding device 5 for progressively folding the advancing web 4 into a tube 3 of packaging material .

In particular, in order to form tube 3 , web folding device 5 is conf igured to progressively fold web 4 from a sheet-like configuration to a C-shaped configuration and then into a substantially tubular shaped configuration .

Preferably, packaging machine 1 comprises a sterili zation unit (not shown) configured for applying a sterili zing agent , for example containing hydrogen peroxide , on web 4 prior to its folding into tube 3 . Packaging machine 1 comprises a forming and sealing unit 6 ( known per se and only schematically shown) for forming tube 3 by imparting a predetermined external shape , corresponding to a precursor of the shape of package 2 , to successive longitudinal portions of tube 3 , and for sealing tube 3 at equally spaced cross-sections .

Packaging machine 1 comprises a filling system 7 ( only partially shown) configured to fill tube 3 with the pourable product .

In detail , filling system 7 comprises a filling pipe 10 which, in use , is inserted and surrounded by tube 3 in formation, and which delivers the pourable product into tube 3 .

In greater detail , filling pipe 10 includes an upper duct 11 , fluidly connected to a pourable product source ( e . g . a tank or reservoir ) , and a lower duct 12 , which is fluidly connected to upper duct 11 and opens into tube 3 for delivering the product therein .

Conveniently, lower duct 12 comprises anti-splash members 13 which are configured to limit backsplashes of pourable product within tube 3 in formation .

Such anti-splash members 13 are defined by discoidal winglets which protrude substantially radially (with respect to a longitudinal axis of lower duct 12 ) from an external surface 12a of lower duct 12 .

In other words , anti-splash members 13 define contoured features of external surface 12a .

Preferably, forming and sealing unit 6 has a longitudinal axis X along which tube 3 is fed, in use .

In particular, such longitudinal axis X is parallel to a straight direction, which preferably is a straight vertical direction, as schemati zed in Figure 1 .

Hence , in use , tube 3 is fed along the longitudinal axis X, downwards , and while being filled from above is formed and sealed by forming and sealing unit 6 .

More speci fically, tube 3 is drawn ( downwards ) along the longitudinal axis X by forming and sealing unit 6 .

In this way, a plurality of pillow packs 2a are obtained .

Packaging machine 1 further comprises a folding unit ( known per se and not shown) for folding the pillow packs 2a, thereby obtaining packages 2 .

In light of the above , the folding unit is configured to output ( i . e . to supply or to provide or to feed) a sequence of fully formed packages 2 containing a pourable product .

Packaging machine 1 further comprises a cleaning unit 8 configured to clean at least one component of packaging machine 1 .

In particular, cleaning unit 8 is configured to clean various components of packaging machine 1 , as it will be better explained in the following .

More precisely, cleaning unit 8 is configured to clean the one or more components of packaging machine 1 during a cleaning process of packaging machine 1 , during which the production is stopped and such components are disassembled from their respective operating positions which they assume during normal use .

More in particular, such components are inserted into cleaning unit 8 in order to be cleaned .

Preferably, such components are manually inserted into cleaning unit 8 .

In particular, once a production cycle is over, or whenever is needed, the packaging machine is stopped and the components to be cleaned, such as the lower duct 12 or the floating element 26 , are temporarily disassembled from their respective operative positions and inserted into the container .

Within the cleaning chamber, a cleaning medium or fluid, such as water or chemically enhanced/ treated water, is dispensed therewithin .

Once cleaned, the components are mounted back in their respective operative positions .

Conveniently, cleaning unit 8 is mounted on a fixed frame 14 of packaging machine 1 , schematically shown in Figure 1 .

According to a preferred embodiment , cleaning unit 8 is configured to clean the aforementioned lower duct 12 of filling pipe 10 , and especially an upper end portion 12b thereof at which said anti-splash members 13 are located .

That is , lower duct 12 , and its upper end portion 12b, define a component ( or part of a component ) to be cleaned by cleaning unit 8 .

To this end, cleaning unit 8 comprises a housing 15 internally defining a cleaning chamber 16 adapted to receive a cleaning medium, such as water or chemically enhanced/ treated water, and the component ( s ) or part of the component ( s ) to be cleaned .

In particular, housing 15 is defined by a substantially cylindrical container or receptacle which is configured to enclose the aforementioned upper end portion 12b of lower duct 12 , as shown in Figure 2 .

Cleaning unit 8 further comprises an elongated housing 17 coupled to housing 15 . Elongated housing 17 defines , in turn, a respective hollow chamber 18 configured for enclosing the rest of lower duct 12 , for the cleaning thereof .

Housing 15 is removably coupled with elongated housing 17 , in order to allow the insertion and/or removal of lower duct 12 , and especially of a lower end portion 12c thereof , within elongated housing 17 , as it will be better described below .

In practice , once lower duct 12 is inserted in cleaning unit 12 , and housing 15 is coupled to elongated housing 17 , its lower end portion 12c is enclosed by elongated housing 17 and its upper end portion is enclosed by housing 15 .

Advantageously, cleaning unit 8 includes a shaped profile within housing 15 , the shaped profile being configured to guide the cleaning medium within cleaning chamber 16 so as to follow an external surface of said component or part of the component , i . e . external surface 12a of the upper end portion 12b of lower duct 12 .

In other words , shaped profile guides , in use , the cleaning medium within cleaning chamber 16 so that the cleaning medium follows external surface 12a, and particularly, the contoured shape thereof defined by anti-splash members 13 .

According to one aspect of the present disclosure , cleaning unit 8 comprises a guide insert 19 arranged within cleaning chamber 16 for surrounding external surface 12a of upper end portion 12b .

Guide insert 19 defines the aforesaid shaped profile and is configured to guide the cleaning medium within the cleaning chamber 16 so as to follow external surface 12a .

In particular, guide insert 19 internally delimits a flow channel 20 for the cleaning medium, the flow channel being shaped so as to follow external contoured features 13 of the component or part of the component to be cleaned, i . e . of upper end portion 12b of lower duct

12 ( according to the preferred embodiment shown) .

That is , flow channel 20 is shaped so as to follow or reproduce the contoured features 13 of upper end portion 12b defined by anti-splash members .

I . e . anti-splash members define such contoured features 13 .

This configuration is shown in Figure 2 .

In practice , guide member 19 delimits a narrow, forced passage , which corresponds to flow channel 20 , for the cleaning medium to completely lap anti-splash members

13 and to flow over and around all the interstices defined by the convoluted and contoured shape of anti-splash members .

In fact , due to their shape , anti-splash members define narrow angles with external surface 12a which in some conditions may be di f ficult to reach by the cleaning medium . In practice , anti-splash members define a rather complicated and contoured geometry including parts which may be di f ficult to reach by the cleaning medium, under some circumstances or machine configurations .

Cleaning unit 8 according to the present disclosure , thanks to the presence of the guide insert 19 and the shaped flow channel 20 , allows for a more ef fective and improved cleaning of lower duct 12 , and especially of the upper end portion 12b thereof (which includes the convoluted and contoured features 13 , in particular defined by anti-splash members ) .

More speci fically, guide insert 19 is provided with an internal geometry which reproduces the "negative" of the external geometry of lower duct 12 , and in particular of its upper end portion 12b . Guide insert 19 is designed in such a way to allow an ef ficient distribution of the cleaning medium around anti-splash members 13 , thus allowing a more accurate cleaning of this area .

In other words , guide insert 19 is provided with a geometry that improves the fluid-dynamics of the cleaning medium in proximity of external surface 12a of lower duct 12 , and in particular at the anti-splash members 13 thereof .

Hence , cleaning unit 8 allows a more ef ficient automatic cleaning of the lower duct 12 . The ef fectiveness of the cleaning process is thereby improved .

As shown in Figure 2 , housing 15 defines a cover for guide insert 19 which surrounds and encloses guide insert 19 and seals cleaning chamber 16 and flow channel 20 in a fluid-tight manner .

Guide insert 19 has central axis A.

In use , housing 15 surrounds guide insert 19 coaxially to axis A. In particular, housing 15 coaxially surrounds guide insert 19 when housing 15 is coupled to elongated housing 17 ( Figure 2 ) .

Guide insert 19 includes an internal surface 21 which delimits flow channel 20 .

It is speci fied that , when lower duct 12 is inserted in housing 15 and guide insert 19 surrounds lower duct 12 , flow channel 20 is delimited on one ( radial ) side by internal surface 21 and on the opposite ( radial ) side by external surface 12a of the lower duct 12 itsel f , at upper end portion 12b .

Conveniently, guide insert 19 extends annularly about axis A.

Accordingly, when lower duct 12 is inserted in cleaning unit 8 , flow channel 20 extends annularly about axis A.

In light of the above , given the contoured shape of upper end portion 12b due to the presence of anti-splash members , flow channel 20 assumes a sort of annular serpentine shape , and follow a z igzagging traj ectory in the axial direction, when lower duct 12 is arranged in cleaning unit 8 .

More speci fically, internal surface 21 has at least a first portion 22 , in particular a plurality of first portions 22 , extending parallel to axis A and at least a second portion 23 , in particular a plurality of second portions 23 , extending transversal to axis A.

In other words , each second portion 23 has a component parallel to the radial direction, relative to axis A.

That is , each second portion 23 is inclined with respect to axis A and to a direction orthogonal to axis A.

This configuration is visible in Figure 2 and in particular in Figure 4 .

In order to define the peculiar shape of flow channel 20 , and in order to determine the following of the contoured external surface 12a at upper end portion 12b and at anti-splash members , each first portion 22 is axially interposed between two second portions 23 , and each second portion 23 is axially interposed between two first portions 22 .

Each first portion 22 and each second portion 23 extend annularly about axis A, so that internal surface 21 is annular about axis A.

Furthermore , internal surface is shaped so as to include a succession of grooves and ribs annularly extending about axis A and extending radially, in particular so as to define a succession of ridges and valleys on internal surface 21 .

To this end, internal surface 21 includes internal first portions 22 which are at a first radial position and external first portions 22 which are at a second radial position radially more external than the first radial position .

Internal first portions 22 and external first portions 22 are axially alternated .

In use , as shown in Figure 2 , the aforementioned radial grooves are engaged by the anti-splash members ( thereby radially facing external first portions 22 ) , while the ribs engage the spaces axially delimited between anti-splash members .

According to a further aspect of the present disclosure , guide insert 19 comprises two hal f-shells 24 internally defining said flow channel 20 and configured to surround, each, a respective angular portion of upper end portion 12b of lower duct 12 , relatively to axis A.

In particular, internal surface 21 is divided into a first surface portion 21a carried by one hal f-shell 24 and a second surface portion 21b carried by the other hal f-shell 24 , in such a way that each hal f-shell 24 delimits a respective portion of the flow channel 20 ( Figure 4 ) .

According to a further aspect of the present disclosure , hal f-shells 24 are arrangeable in :

- an open position ( Figure 4 ) , in which they are spaced from one another to allow the insertion and/or removal of lower duct 12 , and therefore of upper end portion 12b, between them; and

- a closed position ( Figure 3 ) , in which they are in contact with one another so as to define flow channel 20 and to surround lower duct 12 , and in particular upper end portion 12b .

In this way, insertion of lower duct 12 , and especially of its upper end portion 12b which has radially protruding anti-splash members 13 , is eased .

Advantageously, guide insert 19 is integrally fixed to elongated housing 17 by means of a pin 25 that extends axially .

In detail , pin 25 is coupled (preferably welded) to a respective seat obtained in an upper portion of elongated housing 17 , as visible in Figure 2 .

Hence , elongated housing 17 defines a support member for guide insert 19.

More precisely, half-shells 24 are mutually hinged to pin 25 and are thereby configured to rotate with respect to pin 25 selectively away from one another, to define said open position (Figure 4) , or towards one another, to define said closed position (Figure 3) .

In other words, guide insert 19 is fixed in position, and particularly in axial position, on cleaning unit 8 by pin 25, and is openable about a hinge, defining a sort of book-like angular opening rotation of half-shells 24.

This advantageous configuration entails a significant reduction of positioning errors of guide insert 19. Most importantly, an operator is prevented to overlook the insertion of guide member 19 in housing 15 in a very simple manner, due to the fact that guide insert 19 is always fixed in its correct position by pin 25.

Conveniently, guide insert 19, when the half-shells 24 are arranged in a position different from the closed position, has a radial size, with respect to axis A, larger than the radial size of housing 15.

In other words, guide insert 19 with half-shells 24 in a position different from the closed position (i.e. in a position comprised between, and including, the open position and the closed position, but not including this latter) has a radial size, with respect to axis A, larger than the radial size of housing 15.

In light of the above, housing 15 is couplable to elongated housing 17 only when half-shells 24 are arranged in their closed position.

In this way, a poka-yoke system is defined, whereby housing 15 can only be arranged in its operative configuration (i.e. coupled to elongated housing 17) if guide insert 19 is properly closed.

Since the presence of housing 15 is necessary to the functioning of cleaning unit 8, because said housing 15 defines a cover for guide insert 19 which f luid-tightly seals cleaning chamber 16, the aforementioned configuration ensures that half-shells 24 are always properly closed before enclosing them in housing 15, thereby eliminating the risk of errors.

In one embodiment, filling system 7 may further comprise a floating element 26 fitted to lower duct 12, preferably at lower end portion 12c (Figure 1) .

Floating element 26 is configured to measure a filling level of the pourable product within tube 3, according to a manner known and not described in detail.

In some solutions, filling system 7 further comprises :

- a gas feeding duct (not shown) arranged coaxially with filling pipe 10, and particularly with upper duct 11 , so that an annular channel is delimited between the outer surface of filling pipe 10 and the inner surface of the gas feeding duct , which gas feeding duct is designed to feed compressed air through such annular channel and towards the pourable product ; and

- a delimiting plate 27 mounted to the gas feeding duct , arranged within tube 3 and dividing tube 3 into a first compartment ( or first space ) and a second compartment ( or second space ) , the gas feeding duct supplying compressed air into the second compartment .

The purpose of the gas feeding duct and the delimiting plate 27 is to control the pressure within the second compartment , according to a manner known .

Delimiting plate 27 is supported by a holding member 28 , which is preferably mounted on lower duct 12 .

Such components , i . e . floating element 26 , delimiting plate 27 and holding member 28 need to be cleaned during the cleaning process .

To this end, according to a preferred embodiment of the present disclosure , cleaning unit 8 further comprises an additional housing 29 internally defining an additional cleaning chamber 30 configured for receiving floating element 26 , delimiting element 27 and holding member 28 .

Additional housing 29 is mounted onto housing 15 and has : an inlet opening 31 to receive the cleaning medium from a source , and an outlet opening 32 .

In detail , outlet opening 31 is defined by lower duct 12 and is arranged at upper portion 12b .

In greater detail , the cleaning medium is supplied in use from said source through lower duct 12 and into additional cleaning chamber 30 via inlet opening 31 .

Housing 15 is fluidically connected to additional housing 29 via outlet opening 32 .

That is , in use , additional housing 29 feeds the cleaning medium into cleaning chamber 16 and towards guide insert 19 and flow channel 20 via outlet opening 32 , which in turn defines an inlet opening for housing 15 . This configuration is shown in Figure 2 .

The advantages of cleaning unit 8 according to the present invention will be clear from the foregoing description .

In particular, thanks to the presence of the guide insert 19 and the shaped flow channel 20 which follows the contoured features 13 of lower duct , a more ef fective and improved cleaning of lower duct 12 , and especially of the upper end portion 12b thereof (which includes the convoluted and contoured features 13 , in particular being defined by anti-splash members ) is obtained .

More speci fically, guide insert 19 is provided with an internal geometry which reproduces the "negative" of the external geometry of lower duct 12 , in particular its upper end portion 12b . Guide insert 19 is designed in such a way to allow an ef ficient distribution o f the cleaning medium around anti-splash members 13 , thus allowing a more accurate cleaning of this area .

In other words , guide insert 19 is provided with a geometry that improves the fluid-dynamics of the cleaning medium in proximity of external surface 12a of lower duct 12 , and in particular at the anti-splash members 13 thereof .

Hence , cleaning unit 8 allows a more ef ficient automatic cleaning of the lower duct 12 . The ef fectiveness of the cleaning process is thereby improved .

Furthermore , the presence of the hinged hal f-shells 24 entails a signi ficant reduction of positioning errors of guide insert 19 . Accordingly, an operator is prevented to overlook the insertion of guide member 19 in housing 15 in a very simple manner, due to the fact that guide insert 19 is always fixed in its correct position by pin 25 . Moreover, a "poka-yoke" system is defined, whereby housing 15 can only be arranged in its operative ( closed) configuration i f hal f-shells 24 are properly closed .

Since the presence of housing 15 is necessary to the functioning of cleaning unit 8 , because housing 15 defines a cover for guide insert 19 which f luid-tightly seals cleaning chamber 16 , the aforementioned configuration ensures that hal f-shells 24 are always properly closed before enclosing them in housing 15 , thereby eliminating the risk of errors .

Clearly, changes may be made to cleaning unit 8 as described herein without , however, departing from the scope of protection as defined in the accompanying claims .

In particular, housing 15 may directly define the shaped profile, such that guide insert 19 is integrally obtained in a single piece with the housing 15 itself . In such a case, housing 15 would include the two half-shells openable as described above for guide insert 19.

Claims

1.- Cleaning unit (8) for a packaging machine (1) configured to produce sealed packages (2) containing a pourable product, the cleaning unit (8) being configured to clean at least one component (12) of the packaging machine (1) , the cleaning unit (8) comprising a housing (15) internally defining a cleaning chamber (16) adapted to receive a cleaning medium and the component (12) , or part of the component (12) , to be cleaned; wherein the cleaning unit (8) includes a shaped profile within the housing (15) , the shaped profile being configured to guide the cleaning medium within the cleaning chamber (16) so as to follow an external surface (12a) of said component (12) or part of the component (12) .

2.- Cleaning unit (8) as claimed in claim 1, and comprising a guide insert (19) arranged within the cleaning chamber (16) for surrounding at least part of the external surface (12a) of the component (12) or part of the component (12) , the guide insert (19) defining said shaped profile and being configured to guide the cleaning medium within the cleaning chamber (16) so as to follow the external surface (12a) of said component (12) or part of the component (12) .

3.- Cleaning unit (8) as claimed in claim 2, wherein the guide insert (19) internally delimits a flow channel (20) for the cleaning medium, the flow channel (20) being shaped so as to follow external contoured features (13) of said component (12) or part of the component (12) .

4.- Cleaning unit (8) as claimed in claim 3, wherein the guide insert (19) has a central axis (A) and includes an internal surface (21) delimiting said flow channel (20) , said internal surface (21) having at least a first portion (22) extending parallel to the central axis (A) and at least a second portion (23) extending transversally to the central axis (A) or having at least one component parallel to the radial direction, relative to the central axis (A) .

5.- Cleaning unit (8) as claimed in claim 3 or 4, wherein the guide insert (19) has a central axis (A) and an internal surface (21) delimiting said flow channel (20) , wherein the internal surface (21) is shaped so as to include a succession of grooves and ribs annularly extending about the central axis (A) and extending radially; wherein the grooves are configured to be engaged by said contoured features (13) , and the ribs are configured to engage respective spaces delimited between the contoured features (13) .

6.- Cleaning unit (8) as claimed in any one of the claims 3 to 5, wherein the guide insert (19) has a central axis (A) and comprises two half-shells (24) internally defining said flow channel (20) and configured to surround, each, a respective angular portion of said component (12) or part of the component (12) , relatively to said axis (A) .

7 Cleaning unit (8) as claimed in claim 6, wherein the guide insert (19) presents an internal surface (21) delimiting said flow channel (20) , the internal surface (21) being divided into a first surface portion (21a) carried by one half-shell (24) and a second surface portion (21b) carried by the other half-shell (24) , in such a way that each half-shell (24) delimits a respective portion of the flow channel (20) .

8.- Cleaning unit (8) as claimed in claim 6 or 7, wherein the half-shells (24) are arrangeable in:

- an open position, in which they are spaced from one another to allow the insertion of the component (12) or part of the component (12) between them;

- a closed position, in which they are in contact with one another so as to define said flow channel (20) and to surround said component (12) or part of the component ( 12 ) .

9.- Cleaning unit (8) as claimed in claim 8, and comprising a support frame (17) for the guide insert (19) ; wherein the guide insert (19) is integrally fixed to the support frame (17) by means of a pin (25) that extends axially; wherein the half-shells (24) are mutually hinged to the pin (25) and are thereby configured to rotate with respect to the pin (25) selectively away from one another, to define said open position, or towards one another, to define said closed position.

10.- Cleaning unit (8) as claimed in claim 8 or 9, wherein the guide insert (19) , when the half-shells (24) are arranged in a position different from the closed position, has a radial size, with respect to said axis (A) , larger than the radial size of the housing (15) .

11.- Cleaning unit (8) as claimed in claims 9 and 10, wherein the housing (15) is couplable to the support frame (17) only when the half-shells (24) are arranged in said closed position.

12.- Cleaning unit (8) as claimed in any one of the claims 2 to 11, wherein the housing (15) defines a cover for the guide insert (19) which surrounds and encloses the guide insert (19) and seals in fluid-tight manner the cleaning chamber (16) and the flow channel (20) .

13.- Cleaning unit (8) as claimed in any one of the foregoing claims, and comprising an additional housing (29) internally defining an additional cleaning chamber

(30) configured for receiving further components (26, 27, 28) of the packaging machine (1) to be cleaned, the additional housing (29) being mounted onto said housing (15) and having an inlet opening (31) to receive the cleaning medium from a source and an outlet opening (32) , said housing (15) being fluidically connected to the additional housing (29) via said outlet opening (32) , so that the additional housing (29) feeds, in use, the cleaning medium into the cleaning chamber (16) and towards the shaped profile.

14.- Cleaning unit (8) as claimed in any one of the foregoing claims, wherein the cleaning unit (8) is configured to clean a portion (12, 12b) of a filling pipe (11) of the packaging machine (1) , the filling pipe (11) being configured to supply pourable product within a tube (3) of packaging material starting from which the packages (2) are obtained, said portion (12, 12b) of the filling pipe (11) having anti-splash members (13) defining contoured features on said external surface (12a) , wherein the shaped profile (19) is internally shaped so as to follow such contour features (13) .

15.- Packaging machine (1) for the production of sealed packages (2) containing a pourable product starting from a web (4) of packaging material, the packaging machine (1) comprising:

- a device for advancing the web (4) ;

- a web folding device (5) for folding the web (4) into a tube ( 3 ) ; - a forming and sealing unit (6) for forming the tube (3) and sealing the tube (3) thereby obtaining a sequence of packs (2a) ;

- a folding unit for folding the packs (2a) thereby obtaining a sequence of packages (2) ; - a cleaning unit (8) as claimed in any one of the foregoing claims.