EP4106956A1

EP4106956A1 - A method and apparatus for performing quality controls on packages

Info

Publication number: EP4106956A1
Application number: EP21705612.6A
Authority: EP
Inventors: Paola TODERINI; Massimo Fortini; Giuliano Gamberini
Original assignee: GD SpA
Current assignee: GD SpA
Priority date: 2020-02-17
Filing date: 2021-02-05
Publication date: 2022-12-28
Also published as: IT202000003083A1; WO2021165777A1

Abstract

A method is described for performing a quality control on at least one first package element (102) and one second package element (104), which are made by a packaging line configured to produce a package (101) comprising, at least, the first element (102) and the second element (104) arranged inside the first element, The method envisages using a testing station (10) comprising: - at least one manipulator device (11, 12), and - at least one optical detecting unit (14), preferably an image detecting unit; said method including: - providing a package (101) made by the packaging line, which comprises the first element (101) and the second element (104) arranged inside the first element (102); - by means of the at least one manipulator device (11, 12), positioning the first element (102) of the package in one or more predetermined positions with respect to the at least one detecting unit (14); - by means of the at least one detecting unit (14), detecting one or more characteristics of the first element (102) in the one or more predetermined positions; - by means of the at least one manipulator device (11, 12), removing the first element (102) of the package and extracting the second element (104) from the first element (102).

Description

“A method and apparatus for performing quality controls on packages”

& & & &

TEXT OF THE DESCRIPTION

Field of the invention

The present invention relates to a method and an apparatus for performing quality controls on packages.

In the field of packages it is known to perform quality controls along a packaging line to verify the correct operation of the machines of the line. These controls involve using devices capable of detecting one or more characteristics of a package or of an element of the package, which may be positioned within or downstream of one or more machines in the line. In the second case, the detecting device or devices may be positioned in a section of the same packaging line that connects the machine to a downstream station or in a separate station reached by transport means derived from the packaging line.

The controls in question operate to verify a limited number of characteristics, usually a single characteristic for each control, and the relative results are used to modify the operation of the machine if defects are determined.

On the other hand, the quality control of the finished package is, nowadays, carried out by operators in dedicated test centers, which can be set up with various instruments for carrying out the required tests.

The quality control of the products claimed by the present invention not only automates the operations that are carried out manually, but also makes the controls more objective because they are no longer dependent on the skills and attention level of the operator.

In this context, the present invention proposes a new solution for carrying out quality controls on packages which has a series of advantages with respect to the known art, as will be seen below.

In particular, the solution described herein relates to a method according to claim 1, a testing station according to claim 9, and a testing system according to claim 11.

The claims form an integral part of the disclosure provided here.

Further characteristics and advantages of the present invention will become evident from the following description and from the attached drawings, in which:

- Figure 1 represents an embodiment of the testing station described here;

- Figures 2A to 21 schematically illustrate successive steps of an example of implementation of the method described here;

- Figure 3 schematically illustrates a testing system according to the solution described here.

In the following description, various specific details are illustrated aimed at a thorough understanding of the embodiments. The embodiments may be implemented without one or more of the specific details, or with other methods, components, materials, etc. In other cases, known structures, materials or operations are not shown or described in detail to avoid obscuring various aspects of the embodiments.

The references used here are only for convenience and do not therefore define the field of protection or the scope of the embodiments.

As mentioned above, the solution described herein relates to a method and an apparatus for carrying out quality controls on packages. In general, the solution described here regards, above all, a testing station comprising:

- at least one manipulator device;

- at least one optical detecting unit, preferably an image detecting unit; and

- a control unit of the at least one manipulator device and of the at least one optical detecting unit.

According to the solution described here, the indicated testing station is used to perform a quality control on at least one first package element and one second package element made from a packaging line, which is configured for producing a multi-component package comprising, at least, the first element and the second element arranged within the first element. In general, the quality control methods includes the steps of:

- providing a package made by the packaging line, which comprises the first element and the second element arranged inside the first element;

- by means of the manipulator device, positioning the first element of the package in one or more predetermined positions with respect to the at least one image detecting unit;

- by means of the at least one detecting unit, detecting one or more characteristics of the first element in the one or more predetermined positions; - by means of the manipulator device, removing the first element of the package by extracting the second element from the first element.

The solution described here, therefore, envisages carrying out a quality control on a multi-component package that presents the first and the second element to be tested, in a completely automatic way, with the aid of at least one manipulator device and at least one detecting unit, which are arranged to cooperate with each other for carrying out a given test protocol.

The manipulator device is used both to arrange the elements of the package in predefined positions with respect to the detecting unit and to remove the outermost element of the package and to access the inner elements of the package to perform a quality control on these too. The packages may be taken directly from the end of the packaging line.

It will, therefore, be understood that the method described here is capable of controlling the production quality of the various machines of the packaging line through a single testing station, performing a quality control on the finished package containing the respective elements made by these machines.

This allows the provision of a single control center, wherein all the quality controls for a certain packaging line are carried out, and which contains an archive of the results of all the tests performed. The results can then be analyzed by the operators to identify any problems relating to the individual machines of the packaging line.

In some applications, the test results may be directly used by the packaging line for an automatic modification of the operating mode of its machines in order to correct any errors in the process performed. In one or more embodiments, the method envisages comparing data derived from the detecting unit with one or more pieces of reference data and processing a test result based on the comparison performed.

In one or more embodiments, the method envisages storing the data derived from the detecting unit and/or the test result. The method described here has been specifically designed for applications in the field of the packaging of smoking articles, for example, to check the quality of the elements that make up multiple packages of packets of smoking articles (commonly referred to as “cartons”) or individual packets of smoking articles.

In any case, it will be understood that the solution described here can also be indifferently used in other fields, for example, for the packaging of food products, sanitary articles, pharmaceutical products, etc. to name just a few.

With particular reference to the packaging of food products, the solution described here can, for example, be used to perform quality controls on the outer wrapper and on the individual packets of a package of baked goods such as crackers or snacks. In this case, the first element consists of the outer wrapper and the second element consists of the single packet. Again by way of example, the solution described here may be used to perform quality controls on the outer box and on the inner bag of a cereal package, the outer box and the inner bag constituting the first element and the second element, respectively.

Moreover, it should generally be noted that the first element does not necessarily completely enclose the second element, but may, instead, contain it only partially.

Furthermore, as will clearly emerge from the following description, the reference only to the first and second elements is to facilitate the understanding of the general principles of the solution described here; obviously it can also be used to control any additional elements that make up a given package (for example, a third element, a fourth element, etc.).

With reference now to Figure 1, this illustrates an embodiment of the testing station described here.

The illustrated station, generally indicated by the reference number 10, comprises two manipulator devices 11, 12 in the form of two robot arms, which are positioned side-by-side to define a common working space S, placed above a support surface P, within which both robots are able to operate. In the example shown, the two robots are articulated robot arms; in a variant it is possible to provide Cartesian robots.

The station 10 also comprises an optical detecting unit 14, for example, a video camera, which faces the workspace S, and a pair of lighting devices 16, which are positioned on opposite sides with respect to the unit 14 and are also facing the space S.

The station 10 comprises a control unit 20, which is operatively connected to the robots 11, 12 and to the detecting unit 14. The two robots 11, 12 have on their respective ends, as operating units ( end effectors), gripping members 11A, 12A, which each comprise two mechanical fingers 13 opposite and reciprocally movable between an open condition and a closed condition wherein the two fingers are placed in contact with each other. In any case, these members are only examples; in general, the two robots are equipped with gripping members capable of gripping and releasing the portions of the package on which the two robots are intended to operate. Possibly, the two robots may each be arranged with a plurality of gripping members to be used selectively according to the operation to be performed. The station 10 also comprises a free-fall movement channel 17, which is designed to feed the packages to the station 10 by unloading them onto the plane P. The packages unloaded into the channel 17 can be taken as a sample from the end of the packaging line.

Preferably, the two robots 11, 12 are each equipped with a guide system based on a video camera, to control the movement of the robot according to the images acquired by the video camera. In this way, the two robots 11, 12 are able to adapt their movements and their actions according to the present scenario, in particular according to the position and orientation in the space S of the package to be tested. In one or more embodiments, the robots 11, 12 are collaborative robots, or rather, they envisage an operating condition wherein the forces that can be exerted by the robot are limited and the robot can be controlled manually by an operator. This condition can be automatically established as a result of detection by one or more sensors of the presence of an operator near the robot.

This characteristic offers the advantage of allowing an operator to access the testing station at any time, for example, to intervene in the test protocol in progress by the same station.

The testing station described here may - in any case - have alternative configurations to the one illustrated above. For example, the number, position and type of manipulator devices, the detecting units and the lighting devices may be selected according to the needs of specific applications. In particular, in the more simplified form of the station it is possible to provide a single manipulator device. It is also possible to use means other than a robot as a manipulator device; for example, in some variants one of the two illustrated robots may be replaced by a rotatable support arranged with means (for example a gripper) to lock in position the package or the packaging element which are arranged on the support each time. In additional variants, such a support may be provided in addition to the mentioned robots.

Moreover, with reference to the control unit 20 it should be noted that, although in the Figures the control unit is defined by a single block for ease of representation, it may be constituted by a plurality of separate control modules, each configured to implement respective steps of the process illustrated below. Figures 2A-2I illustrate an example of operation of the testing station 10 described above for performing a quality control on a carton 101 of cigarette packets.

Incidentally, it should be noted that this specific application in the field of the packaging of smoking articles is taken into consideration here merely by way of example, and that the test method described here may - in fact - concern, in general, any package for any commercial and industrial sector.

The carton 101 of the illustrated example has a conventional type structure composed of an outer polypropylene wrapper 102, a cardboard container 104 wrapped by the wrapper 102 (Figure 2E), and a plurality of cigarette packets 106 arranged in an orderly manner inside the container 104 (Figure 2H).

Figure 2A represents the carton 101 in the position on the plane P wherein it finds itself at the end of the descent along the channel 17.

The two robots 11, 12 go towards the carton 101, grip it and bring it in front of the video camera 14.

At this point, the two robots 11, 12 arrange the carton 101 according to different orientations to present the different faces of the carton 14 to the camera (Figures 2B, 2C).

The camera 14 acquires the images of all the faces of the carton 101 and transmits them to the control unit 20.

For image acquisition, the single face is arranged with respect to camera 14 in a predefined position, which can be selected according to the characteristic or characteristics to be detected.

For example, to check if the wrapper 102 is perfectly stretched and does not have folds or creases, it is preferable that the axis orthogonal to the face to be filmed is inclined, and not parallel, to the main axis of the visual field of the camera.

In this way, any folds in the wrapper will be optically perceptible to a greater extent.

On the other hand, to check, for example, a position or geometry, it may instead be preferable to arrange the single face orthogonally to the main axis of the visual field of the camera 14, and centered on this axis.

In one or more embodiments, it is possible to arrange the single face, in succession, in multiple predefined positions, according to different angles, with respect to the camera 14, in order to detect different characteristics.

In a similar way, on the basis of the characteristics to be detected, the light beam emitted by the lighting devices 16 can be adjusted with respect to intensity, color, direction, etc. Moreover, this adjustment may also be made on the basis of the conditions of the specific application; for example, the color of the light beam can be adjusted according to the color of the carton.

After the images of all the faces of the carton 101 have been acquired, the two robots 11, 12 operate to remove the outer wrapper 102. To do this, the same opening means with which the carton 101 is provided are advantageously used.

In the illustrated example (Figure 2D), the robot 11 supports the carton 101, while the robot 12 grips the tear strip 108 that is associated with the outer wrapper 102, and pulls it until it is completely unwound from the carton.

The outer wrapper 102 is thus divided into two distinct and separate portions, which are then removed from the container 104 below, by the two robots 11, 12.

At this point, the two robots 11, 12 grip the container 104 without the outer wrapper 102 and position it again in front of the camera 14 to film all its faces by means of said camera (Figures 2E, 2F).

Similarly to what has been described above, the two robots 11, 12 arrange the container 104 according to different orientations to present each face of the container to the camera 14.

As stated above, the single face is arranged in a predefined position with respect to the camera 14, which can be selected according to the characteristics to be detected. For example, to check whether the container 101 respects a given geometry, the single face of the container is arranged orthogonally to the main axis of the visual field of the camera 14, and centered on this axis.

After the images of all the faces of the container 104 have been acquired, the two robots 11, 12 operate to open the container itself.

In the illustrated example (Figure 2G), the robot 11 supports the container 104 while the robot 12 grips the cover 104A and brings it to the fully open position.

The two robots 11, 12 then place the open container 104 in front of the camera 14 and oriented so as to direct its contents towards the camera (Figure 2H). In this way, the camera 14 acquires the image of the upper faces of the packets 106 placed inside the container.

Subsequently, the robots 11 and 12 extract at least one packet 106 from the open container 104: in the illustrated example (Figure 21), the robot 11 holds the container 104 still while the robot 12 grips a packet 106 and extracts it from the container. At this point, the method can envisage carrying out - on the extracted packet - the same type of operations performed on the carton 101.

For example, in the modalities completely similar to those illustrated above, the robots 11, 12 and the unit 14 can:

- acquire images of all the faces of the outer wrapper of the packet; - remove the outer wrapper;

- acquire images of all the faces of the packet devoid of the outer wrapper;

- open the packet

- acquire an image of the packet contents. Furthermore, the cigarettes can be extracted from the packet and - in turn - presented to the camera 14 for further detection.

The images acquired by the camera 14 are used by the control unit 20 to carry out the required controls. These controls may concern all the characteristics of the various elements of the package deemed necessary to ascertain the conformity of the package to a predetermined quality level. For example, these may concern:

- the integrity of the outer wrapper;

- the absence of folds or creases in the outer wrapper;

- the geometry of the cardboard container;

- the folds and glue points of the cardboard container;

- the presence and position of a possible coupon;

- the integrity of the cardboard container;

- the number and orientation of the packets of cigarettes placed in the cardboard container;

- the integrity of the outer wrapper of the single packet of cigarettes;

- the absence of folds or creases in the outer wrapper;

- the geometry of the cigarette packet;

- the folds and glue points of the packet of cigarettes;

- the integrity of the packet of cigarettes;

- the presence and position of a possible tax stamp;

- the number and orientation of the cigarettes contained in the packet.

- the position of the strip and the alignment of the two ends;

- the position and integrity of the inner wrapper: in the case of traditional packets it is the foil or other wrapping material of cigarettes (inner liner), and in the case of e-cig or NGP products it can be a blister or a flow wrap;

- the position and integrity of any adhesive labels applied to the package wrapper (typically containing the codes for the Track & Trace);

- the position and legibility of markings (laser or ink-jet) on the blank of the carton and/or of the packet (typically they contain the codes for the Track & Trace):

- the weight of the package;

- the external appearance of cigarettes (verification of the absence of stains and tears).

Other typical parameters of the quality control of cigarettes (ventilation, degree of humidity of the cigarettes or other smoking articles, etc.) can be verified by this testing station or by an additional dedicated testing station to which cigarettes or other smoking articles are conferred.

For each control, the unit 20 compares the image acquired by the camera 14 with a reference image, and on the basis of the results of the comparison elaborates a positive (“compliant product”) or negative (“defective product”) result.

Preferably, the comparison is based on the determination of one or more characteristics of the acquired image and on the evaluation of the correspondence of these with homologous characteristics of the reference image. Tolerance ranges and/or threshold values can be used to evaluate the conformity of each single characteristic.

The type of characteristic to be determined depends on the control to be performed. The characteristic can, for example, be a dimension, geometry, a shape, a position, a brightness value, etc. In this regard, the control unit 20 can implement any image processing technique known in the automation sector. In alternative embodiments, the reference image may be replaced by simple reference parameters with which to compare the characteristics of the acquired images.

Preferably, the method described here envisages storing both the test results (“compliant product”, “defective product”) and the images acquired by the camera 14. In this way, it is possible to build an archive which the operator can access, when required, to analyze the images of the products found to be defective. On the basis of the results of the tests, it is possible to identify any malfunctions of one of the machines in the line and initiate the appropriate interventions of the case. In some cases, the test results may be used by the same packaging line for automatic modification of the operating mode of its machines in order to correct any errors in the process.

It should be noted that the same testing station of the solution described here can implement test protocols on packages of various types, thanks to the versatile operating mode that the manipulator device or devices are able to adopt. To this end, it is sufficient to load the test protocols and reference images of the various packages to be tested into the control unit of the station.

The solution described here also relates to a system for performing quality controls on packages coming from at least one packaging line, comprising:

- an automatic testing station comprising a control unit; and

- at least one conveying device for feeding packages to the testing station coming from the packaging lines; wherein the control unit of the testing station is configured to store a piece of identifying data of the package fed to the testing station by the conveyor device and the result of the test conducted on the package.

Advantageously, the automatic testing station may be of the type illustrated above. The conveying device may, for example, comprise a free- fall movement channel such as the channel 17 of the example illustrated in Figure 1. The identifying data of the package may come from the same packaging line.

Still another aspect of the solution described here relates to a system for carrying out quality controls on packages coming from different packaging lines. In particular, the system described here comprises:

- an automatic testing station comprising a control unit;

- a plurality of conveying devices for feeding packages to the testing station coming from the various packaging lines; wherein the control unit of the testing station is configured to selectively command one of the conveying devices for feeding a given package to the testing station and for memorizing data identifying the package and a result of the test performed on the package.

Advantageously, the automatic testing station may be of the type illustrated above.

By way of example, Figure 3 illustrates a packaging center comprising a plurality of packaging lines LI, L2 and L3, with which a testing system of the indicated type is associated.

With reference to this Figure, the system in question comprises an automatic testing station 10’ designed to perform quality controls on the various packages coming from the lines LI, L2, L3. The testing station 10’ comprises a control unit 20’.

In general, in some applications, the packages coming from the various packaging lines may be of different types. In this case, the control unit 20’ comprises a memory module containing instructions for a plurality of test protocols, and is configured to extract instructions from the memory module for a given test protocol, according to the type of package to be tested.

The system also comprises a plurality of conveying devices, Tl, T2, T3, which are each associated with a respective packaging line LI, L2, L3 and are designed to feed the relative packages to the testing station 10’.

The conveying devices Tl, T2, T3 are controlled by the control unit 20’ of the testing station 10’.

According to a predetermined criterion, for example, according to a predetermined order, the control unit 20’ activates a given conveying device of the devices Tl, T2, T3, to feed a package made from the relative packaging line at the station 10’.

The control unit 20’ receives at least one piece of data from the same packaging line identifying the package fed to the station 10’.

In the case of packages of different types, on the basis of this data, the unit 20’ selects from the memory unit indicated above the test protocol designated for the type to which the package fed to the station 10’ belongs.

The testing station 10’ therefore performs the selected test protocol, and the control unit 20’ stores the acquired data and the test results together with the identifying data of the package.

Preferably, the system described here is designed to generate an electronic archive of the packaging center, which contains information about the packages tested, such as the production time and the packaging line from which the package was made, and for each package it contains the acquired data and test results.

Of course, without prejudice to the principle of the invention, the details of construction and the embodiments may vary, even significantly, with respect to those illustrated here, purely by way of non-limiting example, without departing from the scope of the invention as defined by the attached claims.

Claims

1. A method for performing a quality control on at least one first package element (102) and one second package element (104), which are made by a packaging line configured to produce a package (101) comprising, at least, the first element (102) and the second element (104) arranged inside the first element, said method including the use of a testing station (10) comprising:

- at least one manipulator device (11, 12); and

- at least one optical detecting unit (14), preferably an image detecting unit; said method including:

- providing a package (101) made by the packaging line, which comprises the first element (101) and the second element (104) arranged inside the first element (102);

- by means of the at least one manipulator device (11, 12), positioning the first element (102) of the package in one or more predetermined positions with respect to the at least one detecting unit (14);

- by means of the at least one detecting unit (14), detecting one or more characteristics of the first element (102) in the one or more predetermined positions;

- by means of the at least one manipulator device (11, 12), removing the first element (102) of the package and extracting the second element (104) from the first element (102).

2. A method according to claim 1, which includes:

-by means of the at least one manipulator device (11, 12), positioning the second element (104) in one or more predetermined positions with respect to the at least one detecting unit (14);

- by means of the at least one detecting unit (14), detecting one or more characteristics of the second element (104) in the one or more predetermined positions.

3. A method according to claim 1 or 2, including comparing data indicative of the characteristics detected by the at least one detecting unit (14) with one or more pieces of reference data and processing a test result on the basis of the performed comparison.

4. A method according claim 3, including memorizing the data indicative of the detected characteristics and/or the test result.

5. A method according to any one of the previous claims, which performs a given test protocol as a function of the configuration of the package to be tested.

6. A method according to claim 5, wherein said method includes:

- receiving data identifying the package to be tested;

- accessing a memory containing a plurality of sequences of instructions for the at least one manipulator device (11, 12) and the at least one detecting unit (14); and

- retrieving a given sequence from the plurality of sequences of instructions, as a function of the received identifying data.

7. A method according to any one of the preceding claims, wherein the testing station (10) comprises a first and a second manipulator device (11, 12), and wherein at least the step of removing the first element (102) is carried out by the first and by the second manipulator devices cooperating with one another.

8. A method according to any one of the preceding claims, wherein the first element (102) is an outer wrapper.

9. A testing station (10), comprising:

- at least one manipulator device (11, 12);

- at least one optical detecting unit (14), preferably an image detecting unit;

- a unit (20) for controlling the at least one manipulator device (11, 12) and the at least one detecting unit (14), which is configured to implement the steps of the method according to any one of the preceding claims.

10. The station according to claim 9, wherein the at least one manipulator device comprises a first and a second manipulator device (11, 12).

11. A system for performing quality controls on packages coming from at least one packaging line, comprising:

- an automatic testing station (10) comprising a control unit (20);

- at least one conveying device (17) for feeding packages to the testing station (10) coming from the packaging line; wherein the control unit (20) of the testing station (10) is configured to memorize data identifying the package fed to the testing station (10) by the conveying device (17) and the result of the test performed on the package.