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(11) | EP 3 115 307 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | QUALITY CONTROL SYSTEM AND METHOD FOR A CONTAINER PROCESSING MACHINE |
| (57) A machine (1) for processing containers (3) has: a conveying device (4); a processing
unit (10), coupled to the conveying device and carrying a respective container (3)
along a processing path (P); an infeed transfer element (5), to transfer onto the
conveying device non-processed containers (3); an outfeed transfer element (8), to
transfer from the conveying device processed containers (3); at least one processing
station (12a), coupled to the conveying device between the infeed transfer element
(5) and the outfeed transfer element (8) to perform processing operations on the container;
and a control system (15) to control quality of the container processing operations,
having a positioning apparatus (16) arranged downstream the infeed transfer element
(5), to set a desired positioning of the container (3) with respect to the processing
unit (10). The control system (15) is also provided with an inspection device (18)
on-board the machine (1), between the positioning apparatus (16) and the processing
station (12a), to: inspect an actual positioning of the container (3) in the respective
processing unit (10), to allow a determination whether the actual positioning corresponds
to the desired positioning; and selectively enable processing operation on the container
by the processing station (12a), based on the determination.
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[0001] The present invention relates to a quality control system and to a quality control method for a container processing machine, in particular for a labelling machine designed to perform labelling operations in the context of filling and packaging of containers for pourable products, such as flat or carbonated liquids, like sparkling water, soft drinks or beer.
[0002] In general, the present solution may be implemented for any type of containers, such as containers or bottles made of glass, plastics, aluminum, steel and composites, and for any type of pourable product, such as carbonated or non-carbonated liquids (including still water, juices, teas, sport drinks, liquid cleaners, wine, etc), emulsions, suspensions and high viscosity liquids.
[0003] As is known, pourable products are packaged in a wide range of containers, which are sterilized, filled and capped in container processing plants, typically including a plurality of processing machines, such as rinsing machines, filling machines, labelling machines and capping machines.
[0004] These processing machines may include linear machines or, more frequently, rotating, or so called "carousel-type", machines.
[0005] The following description will refer to rotating or carousel-type machines only, although this is in no way intended to limit the scope of the present application.
[0006] In particular, labelling machines are known, which are designed to apply labels on containers being processed. Self adhesive labels are often used with bottles or other containers designed to contain pourable products; such labels are obtained by the subsequent steps of: cutting a web of labelling material, unwound from a supply roll, into a plurality of label portions, e.g. of a rectangular or square shape; transferring each label portion onto a respective container; and attaching the label to the same container.
[0007] In particular, rotary labelling machines are known, which comprise a rotary conveyor (so called carousel), which rotates about a vertical axis defining a substantially circular path, along which it is designed to: receive respective sequences of unlabelled containers from an input transfer wheel; apply self-adhesive labels onto corresponding containers; and release the labelled containers onto an output transfer wheel.
[0008] The carousel comprises a number of processing units which are equally spaced about the rotation axis, are mounted along the periphery of the carousel and are moved by the latter along the above-mentioned circular path.
[0009] Each processing unit comprises a supporting element, which is designed to support a bottom wall of a container, and a retaining element, which is designed to engage a top portion of the container to maintain it in a vertical position during the rotation of the carousel.
[0010] Although satisfactory with respect to many aspects, the Applicant has realized that known solutions suffer from some drawbacks.
[0011] In particular, it is possible that labels are applied to the respective containers with a wrong orientation or placement, e.g. due to an initial erroneous positioning of the container on the respective supporting element.
[0012] In this case, there is the risk that the wrongly labelled container is then marketed, with a consequent damage to the image of the product and producer.
[0013] Even in the case that a wrongly labelled container is identified at the end of the processing line, the same container has to be discarded, with a consequent loss of time and resources, particularly if the container has already been filled with the product, since in this case the container, the label and the product are lost.
[0014] Therefore, the need is surely felt for a solution, which may improve quality control of the container processing operations, thus avoiding or reducing the occurrence of wrongly processed containers, thereby reducing waste of time and resources.
[0015] It is an object of the present invention to solve, at least in part, the problems previously highlighted and to satisfy, at least in part, the above need.
[0016] According to an aspect of the present invention, a control system and method for a container processing machine are thus provided, as defined in the appended claims.
[0017] For a better understanding of the present invention, preferred embodiments thereof will now be disclosed by way of non-limitative examples and with reference to the accompanying drawings, in which:
- Figure 1 is a diagrammatic plan view of a container processing machine, according to an embodiment of the present solution;
- Figure 2 is a schematic perspective view, at an enlarged scale, of a portion of the container processing machine, relating to a position inspection device thereof;
- Figure 3 is a diagrammatic plan view of a container processing machine, according to a further embodiment of the present solution;
- Figures 4a and 4b are schematic block diagrams of a control architecture of the container processing machine;
- Figure 5 is a flow chart of control operations performed in the container processing machine.
[0018] Figure 1 shows a container processing machine, of the rotary type, denoted in general with 1, which is configured to carry out labelling operations, so as to apply labels 2, e.g. of the self-adhesive type, on respective containers 3, e.g. glass bottles.
[0019] Each container 3 has a longitudinal axis A, has a bottom wall 3a substantially perpendicular to axis A, and a top neck 3b substantially coaxial with axis A.
[0020] Machine 1 comprises a rotating conveyor 4 (or carousel, as will be denoted in the following), which is mounted to continuously rotate (in a clockwise direction in figure 1) about a vertical axis B perpendicular to a horizontal plane xy (the plane of Figure 1).
[0021] Carousel 4 receives a sequence of unlabelled containers 3, from an infeed wheel 5 (e.g. a starwheel), which is mounted to continuously rotate about a respective longitudinal axis C parallel to axis B, at an input transfer station 5'.
[0022] Infeed wheel 5 in turn receives the unlabelled containers 3 from an infeed linear conveyor 6, e.g. by means of a screw feeder 7, so that they are spaced of a desired pitch.
[0023] Carousel 4 then releases a sequence of labelled containers 3 onto an outfeed wheel 8 (e.g. a starwheel), which cooperates with carousel 4 at an output transfer station 8' and is mounted to continuously rotate about a respective longitudinal axis D, parallel to axes B and C. Outfeed wheel 8 transfer the labelled containers 3 onto an outfeed linear conveyor 9.
[0024] Carousel 4 carries a number of processing units 10, which are equally spaced about axis B and are mounted on the periphery of carousel 4; processing units 10 are displaced by the same carousel 4 along a substantially circular path P, which extends about axis B and from input transfer station 5' to output transfer station 8'.
[0025] Each processing unit 10 is designed to receive a respective container 3 from infeed wheel 5 in a substantially vertical position, i.e. with longitudinal axis A parallel to axes B, C and D, and to maintain container 3 in this position along path P from input transfer station 5' to output transfer station 8'.
[0026] As shown in more details in Figure 2, each processing unit 10 comprises: a base 10a, which is coupled to a horizontal table of a rotating frame 11 of carousel 4 and includes a suitable actuator arrangement 10' (here shown schematically, e.g. including electrical servomotors, or similar actuators) allowing movement of the same base 10a in a three-dimensional space xyz; and a top retaining element 10b designed to engage top neck 3b of container 3, to contribute maintaining the same container 3 in a vertical position.
[0027] Machine 1 further comprises at least a first labelling station 12a (see again Figure 1), arranged laterally and adjacent to frame 11 of carousel 4, including at least a first labelling module 14a (in the example, labelling station 12a further includes a second labelling module 14b), carried by a support platform 13 of the same labelling station 12a.
[0028] In a known manner (here not discussed in detail), each labelling module 14a, 14b includes a web roll of labelling material, and suitable devices to unwind the web roll, cut the web into labels and cause attachment of the labels to the respective containers 3.
[0029] In the example shown, first and second labelling modules 14a, 14b may respectively apply a first label to a front surface of the container 3 and a second label to a rear surface thereof.
[0030] In the exemplary embodiment shown in Figure 1, machine 1 further comprises a second labelling station 12b, that is a slave labelling station, which is brought into an operative condition when the first labelling station 12a, which is a master labelling station, stops working for whatever reason, such as re-loading a new reel of labelling material, the occurrence of program errors, etc., thereby increasing efficiency of the labelling operations.
[0031] Machine 1 further comprises a quality control system 15, coupled to the carousel 4 and configured to control the quality of the labelling operations performed, in particular with respect to orientation and positioning of the labels 2 applied to the respective containers 3.
[0032] According to a possible embodiment of the present solution, quality control system 15 includes a vision apparatus 16 (of a known type, here not discussed in detail), including a suitable arrangement of cameras or similar imaging devices inside a case 16', positioned laterally and adjacent to a first section of the carousel 4, immediately downstream infeed wheel 5. Case 16' is conveniently a box located outside a carousel housing 4' (see Figure 2), for easy access and calibration; a lighting system is usually provided in a separate box positioned inside the carousel housing 4' to provide uniform light with no unwanted reflections and allow proper operation of the cameras or other imaging devices.
[0033] Vision apparatus 16 images the containers 3 transferred on the base 10a of a respective processing unit 10 from the infeed wheel 5, and allows correct positioning thereof, e.g. in terms of the alignment of longitudinal axis A to axis B of machine 1, or centering of the bottom wall 3a of container 3 with respect to the same base 10a, via a suitable driving of the actuator arrangement 10' coupled to the base 10a.
[0034] In a possible embodiment, vision apparatus 16 allows determining the angle of the position of container 3 about its longitudinal axis A; when a correct angle is detected (matching a preset angle exactly or within a given range), a driving signal may be issued to actuator arrangement 10' of base 10a, so that the container 3 is properly positioned.
[0035] The present Applicant has realized that, although it generally ensures that even complex formats of containers 3 are properly positioned (being suitable even for glass and PET, as well other transparent container materials), vision apparatus 16 may not allow proper positioning of the containers 3 in the respective processing units 10, in certain operating conditions, e.g. when reflections impair the correct reading of the position, or in the presence of bubbles, or foam, or imperfectly formed bottles.
[0036] According to a particular aspect of the present solution, quality control system 15 thus further includes at least one positioning inspection device 18, located adjacent the carousel 4, between the vision apparatus 16 and the first labelling station 12a, possibly immediately upstream the same first labelling station 12a with respect to path P.
[0037] As shown in more details in Figure 2, positioning inspection device 18 includes a respective camera or similar imaging apparatus 19, having a field of view V directed to a facing container 3 in the respective processing unit 10.
[0038] Imaging apparatus 19 may be carried by a support structure 20, coupled to housing 4' of the machine 1, within which carousel 4 is located. Imaging apparatus 19 may be coupled to the support structure 20, so as to be able to translate and/or rotate in order to direct the field of view V towards the facing container 3.
[0039] Positioning inspection device 18 is configured to allow checking and verifying if the container 3, each time facing the same positioning inspection device 18 during rotation of carousel 4, has the proper and correct positioning with respect to the processing unit 10.
[0040] Only if a proper positioning is verified, then the first labelling station 12a is allowed to label the container 3, thereby proper application of label 2 is assured. Otherwise, labelling station 12a is instructed not to label the container 3, which therefore proceeds along the rotation path P as an unlabelled container.
[0041] According to a possible embodiment, positioning inspection device 18 may be configured to image a portion of the surface of the container 3, including a specific marking 21, e.g. a line (either straight or curve), a set of lines, a group of characters or signs. The acquired images are then processed in order to indentify the specific marking 21 and verify matching with a preset configuration of the same marking; in case matching is verified (either with an exact correspondence or with a given range of variability), then correct positioning of the container 3 is verified and labelling thereof is allowed.
[0042] In a possible embodiment, positioning inspection device 18 includes local processing capability, in order to process the acquired images, identify the specific marking 21 and determine the correct, or non-correct, positioning of the container 3.
[0043] Positioning inspection device 18 may include a local control unit, schematically denoted with 25 in Figure 2, including a microprocessor, a microcontroller, a DSP - Digital Signal Processor, or similar digital processing unit, configured to receive the images acquired by the imaging apparatus 19 and process the same images to verify correct positioning of the container 3.
[0044] Local control unit 25 may then be configured to issue an enabling/disabling command to the labelling station 12a (e.g. to a control unit thereof), to enable or disable labelling of the container 3, depending on the result of the inspection.
[0045] According to another possible embodiment, the positioning inspection device 18 may instead be configured to send the acquired images to a central control unit 26 (shown schematically in Figure 2), e.g. including a PLC (Programmable Logic Controller) of the machine 1, which is configured to control general operation of the machine 1, and in particular the container labelling operations.
[0046] In this case, the central control unit 26 is configured to process the acquired images in order to verify the correct positioning of the container 3, and issue the enabling/disabling command to the labelling station 12a.
[0047] According to a further aspect of the present solution, the quality control system 15 further includes a labelling inspection device 28, located downstream the output transfer station 8', along the outfeed linear conveyor 9.
[0048] Labelling inspection device 28 is configured to detect any unlabelled containers 3, and allow removal of the same unlabelled containers from the outfeed linear conveyor 9.
[0049] As shown in Figure 3, according to a possible embodiment, machine 1 further includes a return path 30, extending from the outfeed linear conveyor 9, at or downstream the labelling inspection device 28, up to the infeed linear conveyor 6, upstream the infeed wheel 5.
[0050] Return path 30 is selectively enabled in order to return unlabelled containers 3, detected by the labelling inspection device 28, back to the infeed linear conveyor 6, so that they can be correctly labelled during a further labelling operation. In this manner, there is no waste of containers 3, labels 2 or product.
[0051] Return path 30 may selectively be enabled by the same labelling inspection device 28, through suitable mechanical means (of a known type, here not discussed in detail), upon identification of an unlabelled container 3; or by the central control unit 26 of the machine 1, in case the labelling inspection device 28 provides to the same central control unit 26 information required for determination of the presence of unlabelled containers 3 at the outfeed linear conveyor 9.
[0052] As shown in Figure 4a, and based on what previously discussed, a first architecture of quality control system 15 may therefore envisage that the vision system 16, positioning inspection device 18 and labelling inspection device 28 communicate with the central control unit 26 of machine 1, which then issues suitable commands to the support actuator 10', labelling station 12a or return path 30.
[0053] In particular, positioning inspection device 18 may be configured to set a memory register of the central control unit 26, or issue an interrupt to the same central control unit 26, upon determination of the correct/non-correct positioning of the container 3, so that the central control unit 26 may promptly issue enabling or disabling command to the first, master, labelling station 12a (or second, slave, labelling station 12b).
[0054] As shown in Figure 4b, and based on what previously discussed, a second architecture of quality control system 15 may instead envisage a direct communication connection between: the vision system 16 and support actuator 10'; and/or the positioning inspection device 18 and labelling station 12a; and/or the labelling inspection device 28 and return path 30.
[0055] In particular, in this case, positioning inspection device 18 may directly issue an enabling or disabling command to the first, master, labelling station 12a (or second, slave, labelling station 12b), upon determination of the correct/non-correct positioning of the container 3.
[0056] The same vision system 16, positioning inspection device 18 and labelling inspection device 28 may also be configured to communicate with central control unit 26 of machine 1.
[0057] With reference to Figure 5, and based on what previously discussed, operations performed by the quality control system 15 envisage a first step 40, at which images of unlabelled containers 3 transferred from the infeed wheel 5 are acquired by the vision apparatus 16.
[0058] At step 41, the acquired images are processed in order to set a desired orientation of the containers 3, via suitable driving of the actuator arrangement 10 in the respective processing unit 10.
[0059] Next, at step 42, the positioning inspection device 18 images the containers 3, and the acquired images are processed to determine if their positioning is correct and apt to the following labelling operations, at step 43.
[0060] In case it is determined that the position is correct, at step 44, the container 3 is labelled at the labelling station 12a, and afterwards the same container 3 proceeds to the end of line, up to the outfeed wheel 8 and outfeed linear conveyor 9, step 45.
[0061] Instead, in case at step 43 it is determined that the position of the container 3 is not correct, then labelling of the same container 3 by the labelling station 12a is disabled, at step 46.
[0062] The unlabelled container 3 is afterwards identified at the outfeed linear conveyor 9 by the labelling inspection device 28 and the same container 3 is discarded, at step 47.
[0063] Advantageously, upon identification of an unlabelled container 3, the return path 30 is selectively enabled, at step 47, so as to return the identified unlabelled container 3 towards the infeed linear conveyor 6 and the entry point to the machine 1.
[0064] In both cases, operations return to initial step 40, so as to start a new labelling operation.
[0066] In particular, it is underlined that it allows to improve the quality of the container processing operations, and in particular to qualify and certify the accuracy of labelling.
[0067] The discussed solution can be used as a quality control instrument, to ensure with a high degree of precision correct positioning of labels 2 on containers 3.
[0068] Thanks to the discussed solution, waste of resources is therefore avoided, in particular with respect to containers 3, labels 2 and/or the product within the same containers.
[0069] Advantageously, the inspection devices are located on board the machine 1, thus leading to a compact and efficient control arrangement.
[0070] Clearly, changes may be made to the solution disclosed and illustrated herein, without, however, departing from the scope of the present invention, as defined in the appended claims.
[0071] In particular, it is clear that the positioning inspection device 18 may have a different configuration or structure, e.g. including a different kind of imaging device or being coupled to the carousel 4 in a different manner; moreover, the inspection of containers 3 in order to determine their correct positioning may be based upon different or further criteria.
[0072] Moreover, machine 1 could be configured to perform further processing operations on the containers 3, e.g. filling operations in addition to labeling operations.
[0073] In that case, top retaining elements 10b of processing units 10 may be configured to further define a filling device for filling containers 3 with a pourable product. Central control unit 26 may in this case also be configured to control the filling operations, e.g. the sequence and timing of the various operating phases of the filling operations. Accordingly, labelling and filling operations may be jointly managed by a single central control unit 26.
[0074] In particular, in that case, the positioning inspection device 18 may allow to disable not only labelling but also filling of the container 3, if its positioning is determined not to be correct, thereby avoiding label and product waste.
[0075] Moreover, vision apparatus 16 could be replaced with any monitoring apparatus configured to monitor the position of the containers 3 in the respective processing units 10, and allow a desired positioning thereof.
[0076] It is also underlined that the quality control system and method discussed above may be applied to any kind of container processing machine, even for processing operations different from the labeling operations, in all cases in which proper positioning of the containers is required for the processing operations to be performed.
1. A machine (1) for processing containers (3), comprising:
a conveying device (4);
at least one processing unit (10), coupled to the conveying device (4) and carrying a respective container (3) along a processing path (P);
an infeed transfer element (5), coupled to the conveying device (4) at a starting portion of the processing path (P) and configured to transfer onto the conveying device (4) non-processed containers (3);
an outfeed transfer element (8), coupled to the conveying device (4) at an end portion of the processing path (P) and configured to transfer from the conveying device (4) processed containers (3);
at least one processing station (12a), coupled to the conveying device (4) between the infeed transfer element (5) and the outfeed transfer element (8) and configured to perform processing operations on the container (3); and
a control system (15) configured to control quality of the container processing operations, including a positioning apparatus (16) arranged adjacent the conveying device (4), downstream the infeed transfer element (5), configured to set a desired positioning of the container (3) with respect to the processing unit (10),
characterized in that the control system (15) further includes an inspection device (18) arranged on-board the machine (1) adjacent to the conveying device (4), between the positioning apparatus (16) and the processing station (12a), and configured to:
inspect an actual positioning of the container (3) in the respective processing unit (10), in order to allow a determination whether the actual positioning corresponds to the desired positioning; and
selectively enable processing operation on the container (3) by the processing station (12a), based on said determination.
2. The machine according to claim 1, wherein the inspection device (18) includes an imaging
device (19), configured to image the container (3) to allow identification of at least
one positioning marking (21), based on which to perform said determination.
3. The machine according to claim 2, wherein the imaging device (19) has a field of view
(V) designed to be directed towards a surface of the container (3).
4. The machine according to claim 2 or 3, wherein the inspection device (18) further
includes a local control unit (25), coupled to the imaging device (19) and configured
to: process acquired images of the container (3); perform said determination; and
issue an enabling/disabling command to the processing station (12a), to enable, or
respectively disable, operation thereof, based on said determination.
5. The machine according to any of the preceding claims, wherein the processing unit
(10) includes a base (10a) configured to support a bottom wall (3a) of the container
(3) and coupled to which is an actuation arrangement (10'), designed to cause displacement
of the base (10a) ; the positioning apparatus (16) configured to drive the actuation
arrangement (10') to set the desired positioning of the container (3).
6. The machine according to any of the preceding claims, wherein the control system (15)
comprises a further inspection device (28) located downstream the outfeed transfer
element (8), along an outfeed conveyor (9), and configured to identify non-processed
containers (3) carried along by the same outfeed conveyor (9).
7. The machine according to claim 6, further including a return path (30), extending
from the outfeed conveyor (9), at, or downstream, the further inspection device (28),
up to an infeed conveyor (6), upstream the infeed transfer element (5); the return
path (30) designed to be selectively enabled in order to return non-processed containers
(3), identified by the further inspection device (28), back to the infeed conveyor
(6).
8. The machine according to claim 7, wherein the further inspection device (28) is configured
to allow selective enabling of the return path (30), upon identification of a non-processed
container (3).
9. The machine according to any of the preceding claims, wherein the processing station
(12a) is configured to perform labelling operations on the container (3).
10. The machine according to any of the preceding claims, wherein the conveying device
(4) is a carousel configured to rotate about a rotation axis (B).
11. A control method, for a container processing machine (1) having:
a conveying device (4),
at least one processing unit (10), coupled to the conveying device (4) and carrying a respective container (3) along a processing path (P);
an infeed transfer element (5), coupled to the conveying device (4) at a starting portion of the processing path (P) and configured to transfer onto the conveying device (4) non-processed containers (3);
an outfeed transfer element (8), coupled to the conveying device (4) at an end portion of the processing path (P) and configured to transfer from the conveying device (4) processed containers (3);
at least one processing station (12a), coupled to the conveying device (4) between the infeed transfer element (5) and the outfeed transfer element (8) and configured to perform processing operations on the container (3),
the control method designed to control quality of the processing operations, and including setting a desired positioning of the container (3) with respect to the processing unit (10) downstream the infeed transfer element (5) by means of a positioning apparatus (16),
characterized by further including:
inspecting, on-board the machine (1), at a location between the positioning apparatus (16) and the processing station (12a), an actual positioning of the container (3) in the respective processing unit (10) to perform a determination whether the actual positioning corresponds to the desired positioning; and
selectively enabling processing operation on the container (3) by the processing station (12a), based on said determination.
12. The method according to claim 11, wherein inspecting includes imaging the container
(3) to allow identification of at least one positioning marking (21), based on which
to perform said determination.
13. The method according to claim 11 or 12, further comprising: identifying non-processed
containers (3) carried by an outfeed conveyor (9), downstream the outfeed transfer
element (8); and removing the non-processed containers (3) from the outfeed conveyor
(9), upon identification thereof.
14. The method according to claim 13, further including selectively enabling a return
path (30), extending from the outfeed conveyor (9) up to an infeed conveyor (6), upstream
the infeed transfer element (5), in order to return the identified non-processed containers
(3) back to the infeed conveyor (6).
15. The method according to claim 13 or 14, wherein the processing station (12a) is configured
to perform labelling operations on the container (3).