EP4596428A1

EP4596428A1 - Packaging machine for producing sealed packages containing a pourable product, corresponding method and computer program product

Info

Publication number: EP4596428A1
Application number: EP25150818.0A
Authority: EP
Inventors: Giuseppe Esposito; Audun REINSBORGLOG; Gianluca LANDI
Original assignee: Tetra Laval Holdings and Finance SA
Current assignee: Tetra Laval Holdings and Finance SA
Priority date: 2024-01-15
Filing date: 2025-01-09
Publication date: 2025-08-06
Also published as: IT202400000564A1; WO2025153375A1

Abstract

There is described a packaging machine (1) configured for producing sealed packages (2) containing a pourable product, the packaging machine (1) comprising:
- an outfeed conveyor (15), configured to convey the sealed packages (2) along an advancement path (A), the outfeed conveyor (15) being driven by a motor (150),
- a first detector (20), coupled to the motor (150) and configured to generate a first signal (S1) indicative of a movement of the motor (150),
- a second detector (22), configured to generate a second signal (S2) indicative of a presence of sealed packages (2) on the outfeed conveyor (15),
- a printer (24) configured to print a code on the sealed packages (2), and
- a control unit (26) configured to drive the motor (150) as well as the printer (24) and further configured to receive the first (S1) and second (S2) signal, and calculate a printing time as a function of the first (S1) and second (S2) signal.

Description

TECHNICAL FIELD

The present invention relates to a packaging machine for forming packages filled with a pourable product, preferentially a pourable food product. Advantageously, the present invention also relates to a corresponding method and computer program product configured to perform the steps of the method.

BACKGROUND ART

As is known, many liquid or pourable food products, such as fruit juice, UHT (ultra-high-temperature treated) milk, wine, tomato sauce, etc., are sold in packages made of sterilized packaging material.
A typical example is the parallelepiped-shaped package for liquid or pourable food products known as Tetra Brik Aseptic (registered trademark), which is made by sealing and folding laminated strip packaging material. The packaging material has a multilayer structure comprising a base layer, e.g. of paper, covered on both sides with layers of heat-seal plastic material, e.g. polyethylene. In the case of aseptic packages for long-storage products, such as UHT milk, the packaging material also comprises a layer of oxygen-barrier material (an oxygen-barrier layer), e.g. an aluminum foil, which is superimposed on a layer of heat-seal plastic material, and is in turn covered with another layer of heat-seal plastic material forming the inner face of the package eventually contacting the food product.
Packages of this sort are normally produced on fully automatic packaging machines, which advance a web of packaging material through a sterilization apparatus for sterilizing the web of packaging material at a sterilization station and to an isolation chamber (a closed and sterile environment) in which the sterilized web of packaging material is maintained and advanced. During advancement of the web of packaging material through the isolation chamber, the web of packaging material is folded and sealed longitudinally at a tube forming station to form a tube having a longitudinal seam portion, the tube being further fed along a vertical advancing direction.
For completing the forming operations, the tube is filled with a pourable product, in particular a pourable food product, and is transversally sealed and subsequently cut along equally spaced transversal cross sections within a package forming apparatus of the packaging machine during advancement along the vertical advancing direction.
Pillow packages are so obtained, each pillow package having a longitudinal sealing band, a top transversal sealing band and a bottom transversal sealing band.
Finally, the so-called pillow packages are folded into the final package by a final folding machine and moved onto a conveyor configured to convey the packages towards further handling stations. For example, the packages on the conveyor may transit at a printing station where a code, such as the best before date, is printed on the package.
The production of the packages is subject to events, that may lead to variations in speed and/or number of the packages present in the conveyor. In certain cases, such variations can generate inaccuracies in the printing of the packages, for example the printing may be off centered.
Even though the known packaging machines work satisfactorily well, a desire is felt in the sector to further improve the accuracy of the known packaging machines in production of packages.

DISCLOSURE OF INVENTION

It is therefore an object of the present invention to provide an improved packaging machine able to address the known drawbacks.
It is an object of the present invention to provide an improved method for printing on sealed packages produced in a packaging machine able to address the known drawbacks.
According to the present invention, there is provided a packaging machine as claimed in claim 1. According to the present invention, there is also provided a method according to claim 14.

BRIEF DESCRIPTION OF THE DRAWINGS

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

Figure 1 is a schematic view of a packaging machine according to the present invention, with parts removed for clarity;
Figures 2 and 3 are schematic side and top view, respectively, of a detail of the packaging machine according to the present invention, with parts removed for clarity;
Figure 4 is a schematic representation of a detail of the packaging machine according to the present invention.

BEST MODES 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 e.g. paper or cardboard, and at least two layers of heat-seal plastic material, e.g. polyethylene, interposing the layer of fibrous material in between one another. Preferentially, one of 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.
Preferentially, web 3 comprises successively arranged patterns, each pattern defining a final graphical pattern of the respective package 2. In other words, packaging machine 1 operates, in use, such to guarantee that packages 2 comprise the respective pattern.
Furthermore, packaging machine 1 may be configured to produce packages 2 by forming a tube 4 from web 3, longitudinally sealing tube 4, filling tube 4 with the pourable product and to transversally seal, and preferentially transversally cut tube 4.
According to some possible embodiments, each package 2 may comprise at least a first transversal sealing band 5 arranged at a first end of package 2, and preferentially also a second transversal sealing band arranged at a second end of package 2 opposite to the first end.
Preferentially, each first transversal sealing band 5 may define a transversal top sealing band and each second transversal sealing band may define a transversal bottom sealing band.
Moreover, each package 2 may also comprise a longitudinal seam portion 6. Preferentially, each first transversal sealing band 5 and/or each second transversal sealing band may be transversal, preferentially perpendicular, to the respective longitudinal seam portion 6.
With particular reference to Figure 1, packaging machine 1 may comprise a package forming apparatus configured to transversally seal, and to transversally cut tube 4 for obtaining semi-finalized packs or pillow packs 7. Preferentially, package forming apparatus 10 may also be configured to form tube 4.
Additionally packaging machine 1 may comprise a final folding apparatus 10, shown in figures 2 and 3, configured to receive the semi-finalized packs 7 and to form packages 2 from the semi-finalized packs 7. In other words, the final folding apparatus 10 is configured to fold semi-finished packs 7 into the sealed folded packages 2.
Moreover, packaging machine 1 may also comprise one or more of:

a conveying device 11 configured to advance web 3 along a web advancement path P, preferentially to a tube forming station, at which, in use, web 3 is formed into tube 4, and configured to advance tube 4 along a tube advancement path Q;
a tube forming and sealing device 12 configured to form tube 4 from the, in use, advancing web 3 and to longitudinally seal tube 4; and
a filling device 13 for filling tube 4 with the pourable product.

The packaging machine 1 comprises an outfeed conveyor 15, configured to convey the sealed packages 2 along an advancement path A, wherein the outfeed conveyor 15 is driven by a motor 150.
The movement of the outfeed conveyor 15 may be synchronized with the movement of the final folding apparatus 10. The outfeed conveyor 15 may be positioned (e.g. immediately) downstream of the final folding apparatus 10 according to the advancement path A.
The packaging machine 1 may comprise:

a first detector 20, coupled to the motor 150 and configured to generate a first signal S1 indicative of a movement, e.g. an angular position, speed and/or acceleration, of the motor 150,
a second detector 22, configured to generate a second signal S2 indicative of a presence of sealed packages 2 on the conveyor 15.

The packaging machine 1 may comprise a printer 24 configured to print a code, e.g. a best before date or an alphanumerical code, on the sealed packages 2. The printer 24 may be positioned at the outfeed conveyor 15. The printer 24 may be configured to print the codes on the packages 2 on the outfeed conveyor 15. The printer may be positioned downstream of the final folding apparatus 10.
The packaging machine 1 may comprise a control unit 26 configured to drive the motor 150 as well as the printer 24 and further configured to receive the first and second signal S1, S2, and calculate a printing time as a function of the first and second signal S1, S2.
In particular, the printing time may be adapted for each detected package 2 based on the first and second signals S1, S2.
Advantageously, the control unit 26 may be the packaging machine control unit, configured to control the operation of the packaging machine as well as the detectors 20, 22 and the printer 24.
In particular, the printing time may be indicative of a time between a detection of the presence of the sealed package 2 at the second detector 22 and a presence of the sealed package 2 at the printer 24. In particular, the printing time may be adapted based on the first signal S1, i.e. based on the movement of the motor 150, preferably based on an angular position of the axis of the motor 150 and/or its speed. Advantageously, in case an event occurs in the operation of the machine 1, the printing time may be continuously and dynamically adapted based on variations of the movement of the motor 150.
The first detector 20 may be integrated in the motor 150. In particular, the first detector 20 may be thus positioned within the packaging machine 1. The first detector 20 may be coupled with the control unit 26 of the packaging machine 1. Advantageously, the detector is a part of the packaging machine and not an external object adapted therein. This way, the accuracy is improved and the complexity of the system is reduced.
In particular, the motor 150 is a rotative motor, configured to move the outfeed conveyor 15 as a result of its rotation and the first detector 20 is an encoder integrated in the rotative motor. The first detector 20 may be configured to detect a position of the axis of the rotative motor.
The second detector 22 comprises a contactless detector, configured to detect the presence of the packages 2 without interfering with the movement thereof. In particular, the second detector 22 may comprise an optical detector, preferably a photocell.
The control unit 26 may be configured to receive an event signal indicative of an event in operation of the packaging machine 1. The event may comprise a deceleration and/or acceleration in the production of the packages 2, preferably between 24000 packages per hour and 42000 packages per hour. For example, such event comprises a bucket refill, where the number of packages 2 produced varies for a certain period of time. A deceleration of the packages 2 on the conveyor occurs, followed by an acceleration.
The control unit 26 may be configured, if an event is detected, to calculate the printing time as a function of the first and second signal S1, S2.
Advantageously, the control unit 26 may be configured to calculate and/or update the printing time only if an event occurs. During normal operation, the printing time may be constant.
The control unit 26 may be configured to calculate the printing time as a function of the movement of the motor, e.g. a position of the axis of the motor 150, the presence of the package 2 on the outfeed conveyor 15 and a predetermined distance D between the second detector 22 and the printer 24.
Advantageously, the accuracy of the print is independent of the position of the printer. In particular, advantageously the distance D between the detector 22 and the printer 24 may be a predetermined parameter.
Accordingly, the packaging machine 1 may comprising a human machine interface (not visible in the figures). The predetermined distance D is inputted in the human machine interface.
Advantageously, the control of the printing time and the trigger is part of the packaging machine. However, the configuration of the printer 24 is not modified. Accordingly, a precise control can be achieved without modifying settings/parameters of the external printing system.
The control unit 26 may be configured to, when the the presence of a package is detected, request a first signal S1 from the first detector 20. In other words, when the second signal S2 indicates that a package 2 is present, the first detector 20 transmits the first signal S1 to the control unit 26.
Advantageously, the trigger to receive a first signal from the first detector may be synchronized with the detection of the package. This way, a precise indication of the movement, and in particular the position and speed, of the motor 150 is achieved. A precision of the printing on the package may be vastly improved thanks to the precise calculation based on the movement of the motor, in particular thanks to the position and/or speed of the axis of the motor.
Accordingly, a trigger to request the first signal S1 may be based on the second signal S2, in particular based on the detection of the presence of the package 2 at the second detector 22. The first signal S1 may comprise the position of the axis of the motor 150 when the package 2 transits at the second detector 22. The printing time may thus be adapted based on the position of the axis of the motor 150.
The control unit 26 may be configured to periodically receive the first signal S1 from the first detector 20. However, the control unit 26 may be configured to receive the first signal S1 also when the package 2 transits at the second detector 22. Advantageously, a movement of the motor 150 is continuously monitored, in particular its position and/or speed. At the same time, it is possible to monitor the position of the motor 150 at strategic time instants, such as the transition of the packages at the second detector.
The packaging machine 1 may comprise a camera 28 positioned downstream of the printer 24 according to the advancement path A. The camera 28 is configured to capture an image of a printed portion of the sealed package 2, e.g. a top surface of the sealed package 2. The control unit 26 may be coupled to the camera 28 and receive the image therefrom. Based on the image, the control unit 28 may be configured to adjust the printing time. For example, the image may be indicative of the printed code being positioned offset with respect to the surface of the sealed package 2.
The present disclosure further relates to a method for printing on sealed packages produced in a packaging machine (1) according to the present description. The method may comprise:

receiving a first signal S1 indicative of a movement, e.g. position oof the axis or speed, of the motor 150,
receiving a second signal S2 indicative of a presence of sealed packages 2 on the conveyor 15,
printing a code on the sealed packages 2,
calculating a printing time as a function of the first and second signal S1, S2, and
driving, by means of signal S3, the printer 24 as a function of the calculated printing time.

The method may comprise, when (e.g. at the exact moment that) the presence of a package is detected, requesting a first signal S1 from the first detector 20. The method may comprise periodically receiving the first signal S1 from the first detector 20.
The present disclosure may further relate to a computer program product loadable in the memory of at least one electronic control unit, such as control unit 26, and comprising software code portions suitable for performing the steps of the method as described herein.
The instant solution provides one or more advantages:

an accuracy of the printing is vastly improved, e.g. error in printing may be lower than <0.1mm, thanks to calculating a position offset,

the trigger S3 to control the printing on the packages may be generated by the movement of the motor (e.g. position) and not by time delay,
the solution may be robust towards capacity transients of the packaging machine, i.e. the printing position dependence on the speed variation of the packages may be reduced.

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

Claims

A packaging machine (1) configured for producing sealed packages (2) containing a pourable product, the packaging machine (1) comprising:
- an outfeed conveyor (15), configured to convey the sealed packages (2) along an advancement path (A), the outfeed conveyor (15) being driven by a motor (150),

- a first detector (20), coupled to the motor (150) and configured to generate a first signal (S1) indicative of a movement of the motor (150),

- a second detector (22), configured to generate a second signal (S2) indicative of a presence of sealed packages (2) on the outfeed conveyor (15),

- a printer (24) configured to print a code on the sealed packages (2), and

- a control unit (26) configured to drive the motor (150) as well as the printer (24) and further configured to receive the first (S1) and second (S2) signal, and calculate a printing time as a function of the first (S1) and second (S2) signal.
The packaging machine (1) according to claim 1, wherein the first detector (20) is integrated in the motor (150), preferably the first detector (20) is an encoder.
The packaging machine (1) of claim 1 or claim 2, wherein the motor (150) is a rotative motor and the first detector (20) is configured to generate the first signal (S1) indicative of an angular position of the axis of the rotative motor.
The packaging machine (1) according to any of the previous claims, wherein the first signal (S1) is indicative of a position and/or speed of the motor (150).
The packaging machine (1) according to any of the previous claims, wherein the second detector (22) is a contactless detector, preferably an optical detector such as a photocell.
The packaging machine (1) according to any of the previous claims, wherein the control unit (26) is configured to receive an event signal indicative of an event in operation of the packaging machine (1) and, if an event is detected, calculate the printing time as a function of the first (S1) and second (S2) signal.
The packaging machine (1) according to claim 6, wherein the event comprises a deceleration and/or acceleration in the production of the packages (2), preferably between 24000 packages per hour and 42000 packages per hour.
The packaging machine (1) according to any of the previous claims, further comprising a final folding apparatus (10) configured to fold semi-finished packs (7) into the sealed folded packages (2), the final folding apparatus (10) positioned upstream of the outfeed conveyor (15) along the advancement path (A).
The packaging machine (1) according to any of the previous claims, wherein the control unit (26) is configured to calculate the printing time as a function of the first signal (S1), the second signal (S2) and a predetermined distance (D) between the second detector (22) and the printer (24) .
The packaging machine (1) according to claim 9, comprising a human machine interface, wherein the predetermined distance (D) is inputted in the human machine interface.
The packaging machine (1) according to any of the previous claims, wherein the control unit (26) is configured to, when the presence of a sealed package (2) is detected, request a first signal (S1) from the first detector (20).
The packaging machine (1) according to any of the previous claims, comprising a camera (28) positioned downstream of the printer (24) according to the advancement path (A), the camera (28) configured to capture an image of a printed portion of the sealed package (2), wherein the control unit (26) is configured to receive the image and adjust the printing time as a function of said image.
The packaging machine (1) according to any of the previous claims, wherein the control unit (26) is configured to periodically receive the first signal (S1) from the first detector (20).
A method for printing on sealed packages (2) produced in a packaging machine (1) according to any of the previous claims and advancing along an advancement path (A) on an outfeed conveyor (15) being driven by a motor (150), the method comprising:
- receiving a first signal (S1) indicative of a movement of the motor (150),

- receiving a second signal (S2) indicative of a presence of sealed packages (2) on the conveyor (15),

- printing a code on the sealed packages (2),

- calculating a printing time as a function of the first (S1) and second (S2) signal, and

- driving (S3) the printer (24) as a function of the calculated printing time.
A computer program product loadable in the memory of at least one control unit (26) and comprising software code portions suitable for performing the steps of the method according to claim 14.