Labelling station for a labelling machine for labelling containers

Abstract

The invention relates to a labelling station (1) for a labelling machine for labelling containers (3), in particular beverage containers, with an application carousel (12) for applying labels to the containers (3) and with a feed device (9) for feeding the labels into the application carousel (12), wherein the feed device (9) has at least one cutting apparatus (10) for separating individual labels from a label strip (4) and wherein the label strip (4) can be moved along a feed section (Z) within the feed device (9). According to the invention, the feed device (9) has a suction apparatus (13) with a suction chamber (15), wherein the suction chamber (15) extends along a portion of the feed section (Z).

Description

[0001] Labeling station for a labeling machine for labeling containers

[0002] Description

[0003] The present invention relates to a labeling station for a labeling machine for labeling containers, in particular beverage containers, having an application carousel for applying labels to the containers and having a feed device for feeding the labels to the application carousel, wherein the feed device has at least one label drive for driving a label strip and a cutting device for separating individual labels from the label strip, and wherein the label strip is movable within the feed device along a feed path.

[0004] The invention relates in particular to labeling stations for labeling machines used in the beverage industry, so that the beverage containers are preferably glass or plastic beverage bottles. If the beverage bottles are made of plastic, this is particularly a thermoplastic, in particular polyethylene terephthalate (PET), so that the beverage bottles can be easily formed using a so-called stretch blow molding process.

[0005] Typically, the necessary stretch blow molding machines are part of a filling line, so the beverage bottles are first formed from preforms during the stretch blow molding process and then filled. A labeling machine may then be included.

[0006] The invention relates to so-called roll-fed labelers. In such roll-fed labelers, the labels are provided in the form of a label strip. Accordingly, the labels are not provided individually. Rather, a plurality of labels are arranged one behind the other in the form of an endless strip, with the labels being separated from the label strip in a cutting device before being applied to the containers. Furthermore, a pressure-sensitive adhesive can also be applied to the labels, provided the label strip does not already contain a pressure-sensitive adhesive. The labels are then applied to the containers.

[0007] Labeling stations of the type described above have generally proven themselves in the state of the art. However, it has also been shown that feeding a label strip can be problematic, especially when shutting down and restarting the feed device. It should be noted that the label strip is usually in the form of a wound supply roll arranged on driven supply roll holders. A label drive is also provided within the feed device, so that the movement of the label strip is caused by the rotation of the supply roll holders on the one hand and by the label drive on the other.

[0008] Since new types of labeling machines in the form of roller-type labeling machines are often part of a combined filling system, the containers are labeled immediately before or after filling in the filling system. However, due to the upstream blow molding machine in particular, it may happen that individual positions in the blow molding machine, and thus also in the subsequent labeling machine, are undesirably not occupied by a container. Accordingly, individual positions in a transport carousel of the labeling machine assigned to the application carousel may be unoccupied, making the application of a label unnecessary or even impossible.

[0009] It is known from practice that the labels that are then fed in are vacuumed or removed in some other way, although this is often not desired, especially with regard to efficient and resource-saving use of the label material.

[0010] Against this background, occupancy sensors are often provided which detect a free container receptacle in the transport carousel. In such a case, the label drive is stopped for a short period of time so that no label is fed while the free container receptacle moves past the application carousel. This stopping and restarting of the label drive takes place in a very short period of time, in the range of a few milliseconds. However, this stopping results in the label strip being fed further and losing its tension, precisely because of the inertia of all the moving masses in the label path and in particular because of the inertia of the supply roll holders, so that the label can fall off within the feed device.Resuming the label strip can cause such a disturbance that, depending on the label material, this can lead to various problems. If the label strip is made of plastic film, the abrupt restart will cause the label strip to elongate and thus potentially misposition the labels on the containers. If the label strip is made of paper, the abrupt braking and restart can cause the label strip to tear.

[0011] The invention is based on the object of providing a labeling station which enables the label drive to be stopped and started quickly while simultaneously treating the label strip gently.

[0012] The invention relates to a labeling station. According to the invention, the feed device comprises a suction device with a suction chamber, the suction chamber extending along a section of the feed path.

[0013] The suction chamber forms an area into which the excess material from the label strip can be fed when the label drive is switched off, thanks to the continuously applied negative pressure. The special feature here is that the negative pressure does not need to be particularly high for the excess material to be fed in. This means that when the label drive is restarted, the label strip can be easily removed from the suction chamber without significant force, whereby the forces are not sufficient to adversely affect the endless strip in any way.

[0014] At the same time, it is also possible to react particularly quickly to the switching of the label drive because, as already explained, the negative pressure is continuously applied and thus the label strip is continuously sucked in. In normal operating conditions, the label strip is guided past an opening in the suction chamber, whereby the forces caused by the negative pressure are not sufficient to suck in the label strip. Immediately after the label drive is switched off, the negative pressure then acts on the label strip in such a way that the excess material is sucked in. The invention takes advantage of the fact that the label strip is often made of a relatively light and thin material and is therefore particularly flexible in a direction transverse to the feed path.A buffered length by which the label tape would slacken if it were not sucked into the suction chamber to maintain a certain tautness is between 1 cm and 4 cm, in particular between 2 cm and 3 cm long.

[0015] According to a further development of the invention, the feed device has a label drive, wherein the suction device is arranged along the feed path upstream of, in particular directly upstream of, the label drive. As already explained above, the label strip is moved by the feed device, wherein when the label drive stops, the greatest accumulation of material occurs directly upstream of the label drive due to the inertia of the moving masses. In this respect, the arrangement of the suction device upstream of the label drive is particularly advantageous, since the excess material can then be picked up directly where it is created. In this context, it should be noted that the terms "upstream" and "downstream" refer to the operational direction of movement of the label strip along the feed path.

[0016] A preferred embodiment of the invention further provides that the label drive is arranged between the cutting device and the suction device. Thus, stopping the label strip also interrupts its feed into the cutting device.

[0017] A further development of the invention further provides that the suction chamber is connected to a vacuum device for generating a negative pressure. In this context, a vacuum device is understood to be a device that can generate a negative pressure compared to the environment in the labeling station. In the simplest case, the negative pressure device is at least one fan which, when driven, draws the ambient air out of the suction chamber. Of course, several fans can also be provided, with the number of fans being based in particular on the power required to generate the negative pressure in the suction chamber. In practice, it has been shown that the use of three fans is particularly expedient.The vacuum device can then be formed directly on the suction device and interact with the suction chamber in such a way that the suction chamber has a negative pressure compared to the environment in the labeling station.

[0018] A particularly preferred embodiment of the invention provides that an opening of the suction chamber associated with the feed path is adjustable. This makes it possible to adjust the opening to the size of the label strip. This allows the opening to be limited to a size just large enough for the label strip to enter the suction chamber. At the same time, the negative pressure in the suction chamber can have a particularly effective effect on the label strip. If, for example, the opening is significantly larger than the height of the label strip, a large portion of the ambient air from the labeling station would enter the suction chamber, thereby reducing the effectiveness of the suction device.

[0019] Particularly preferred in this context is a configuration in which a lower edge and / or an upper edge of the opening of the suction chamber are adjustable. Typically, the lower edge or the lower boundary of the suction chamber does not change when the format is changed, so this lower edge is adjusted before the label machine is put into operation for the first time. Of course, it is also conceivable that realignment of the lower edge may be necessary over time. Accordingly, the size of the opening in relation to the height of the label strip can be adjusted using the upper edge alone. This can be done, for example, when changing formats manually, e.g. using a hand lever or a handwheel.

[0020] A particularly preferred embodiment is one in which the upper edge is adjustable via a servomotor connected to a control unit. This makes it possible for a format change, depending on the container, to send a command via the control unit to the servomotor, so that an automatic adjustment in the suction device occurs. The servomotor is, in particular, an electric motor, e.g., an electric spindle motor. The electric motor then acts on a spindle, which, by rotating, causes an adjustment of the upper edge in relation to the label height.

[0021] A further development of the invention provides that the feed device has at least one supply roll holder for receiving the label strip wound into a supply roll and a web tensioning device arranged behind the supply roll holder. This web tensioning device makes it possible to ensure uniform web tension regardless of the operation of the labeling station. The web tensioning device can be designed like a pulley and cause the label strip to be deflected several times. By adjusting the distances between the rollers, the feed path can then be increased or decreased depending on the operating point in order to ensure uniform web tension. In contrast to the suction device, however, this web tensioning device is considerably slower and therefore cannot compensate for the short-term fluctuations during the aforementioned start-up and stop-down.

[0022] The application carousel is preferably designed as a rotatably mounted vacuum drum. Accordingly, the labels are held to the application carousel by vacuum.

[0023] Furthermore, the feed device can also include a gluing device for applying a pressure-sensitive adhesive. The gluing device is preferably designed as a rotatably mounted glue roller.

[0024] The invention further relates to a labeling machine with a transport carousel for moving the containers along a transport path and at least one labeling station according to the invention, wherein the transport carousel is directly adjacent to the application carousel of the labeling station. Accordingly, the movement of the containers is effected via the transport carousel, and the moving labels or label strip via the labeling station. The transport carousel and the application carousel are arranged at a distance from each other that allows the labels to be applied to the container.

[0025] Preferably, the container receptacles of the transport carousel are designed to be rotatable, so that the containers rotate not only due to the rotation of the container carousel, but also simultaneously around their container axis. This allows the label to be applied and pressed onto the containers particularly well.

[0026] The invention further relates to a container treatment system comprising a blow-molding machine for blow-molding, in particular for stretch blow-molding, containers from plastic preforms, and a labeling machine according to the invention, which is integrated with the blow-molding machine, for labeling the containers. The container treatment system has a central control system configured to control the label drive and the suction device depending on the operation of the blow-molding machine such that, in the event of an interruption in the flow of containers from the blow-molding machine to the labeling machine, the supply of labels to the application carousel of the labeling station is interrupted, and the label strip is held at a predetermined tension by means of the suction device.

[0027] In the context of the invention, interlocking means that no transport devices that could form a container buffer are provided between the individual machines. Instead, the machines are preferably connected to one another via transport star wheels, in particular exclusively via transport star wheels.

[0028] It is preferably provided that the container treatment system has a filling machine which is connected to the labelling machine and is used to fill the containers with a liquid filling product, in particular a beverage.

[0029] Furthermore, the invention also relates to a method for labeling containers in a labeling machine according to the invention, wherein the containers are fed to the transport carousel and transported along the transport direction and wherein a label strip is moved along a feed path, individual labels are separated from the label strip and applied to the containers via the application carousel.

[0030] The labels can also be glued with a pressure-sensitive adhesive, provided that the label tape itself is designed without a pressure-sensitive adhesive.

[0031] The label tape is particularly preferably made of a plastic film or paper.

[0032] Preferably, the label strip is continuously subjected to a negative pressure along a section of the feed path via the suction device. In the event of a standstill of the feed device, the label strip particularly preferably rests in sections in the suction chamber of the suction device.

[0033] According to a preferred embodiment of the method, the containers are first formed from plastic preforms in a blow molding machine by blowing, in particular by stretch blow molding, and then fed to the labeling machine which is connected to the blow molding machine.

[0034] Preferably, in the event of an interruption of a container flow from the blow molding machine to the labeling machine, a supply of labels to the application carousel of the labeling station is interrupted and the label strip is held at a predetermined tension by means of the suction device.

[0035] The invention is explained in more detail below using an exemplary embodiment. The figures show:

[0036] Figure 1 shows a labelling machine according to the invention in a plan view,

[0037] Figure 2 shows the intake device in an isometric view,

[0038] Figure 3 shows the suction device according to Figure 2 with a label strip shown, Figure 4 shows a suction device in a sectional view, which allows a view into the suction chamber 15 and shows its small depth (in relation to the length of the label strip being guided past),

[0039] Figure 5 shows a suction device according to Figure 3 with a sucked-in label strip.

[0040] Figure 1 shows a labeling machine with a labeling station 1 designed as a roll-fed labeling station, which is directly connected to a transport carousel 2, shown only schematically, for transporting containers 3. The labels are applied to the containers 3 via the labeling station 1, wherein the labels are initially provided in the form of a label strip 4, which is stored in supply roll holders 5 in the form of wound supply rolls 6. By rotating the supply roll holders 5, the label strip 4 is unwound and simultaneously fed to a web tensioning device 7, which ensures uniform web tension within the label strip 4 by moving the guide rollers relative to one another.

[0041] In addition to the rotation of the supply roll holders 5, a label drive 8 also causes the label strip 4 to move through a feed device 9 of the labeling station 1, wherein the label strip 4 can be cut into individual labels in a cutting device 10, provided with a pressure-sensitive adhesive via a gluing device 11, and applied to the containers 3 via an application carousel 12. For this purpose, the containers 3 roll within the transport carousel 2 around their own container axis, whereby the labels can be applied particularly advantageously to the outer surface of the containers 3.

[0042] If individual container receptacles of the transport carousel 2 are not occupied, an occupancy sensor (not shown in detail) detects the remaining container receptacle and reports this to a control unit (also not shown). The label drive 8 is then stopped to prevent a label from being fed to the remaining container receptacle. This then leads to material of the label strip 4 accumulating, particularly immediately in front of the label drive 8, which falls downwards due to its own weight when the carousel is at a standstill due to the lack of web tension. When the carousel is resumed, the web tension is increased again, whereby the short time intervals can have a disadvantageous effect on the label strip 4 in several respects. Furthermore, due to the inertia of the system, the web tensioning device 7 is not sufficient to prevent the accumulation of excess material of the label strip 4.Against this background, a suction device 13 is provided, which is shown in more detail in Figures 2 to 4.

[0043] Figure 2 shows the suction device 13 in a rear view, wherein a vacuum device 14 formed by three fans creates a negative pressure in a suction chamber 15. This suction chamber extends parallel to the label strip 4.

[0044] The suction device 13 also has an opening 16, wherein, in an operating state, the label strip 4 runs past the opening 15. This is particularly clearly evident from Figure 3.

[0045] The opening 16 and thus also the suction chamber 15 extend over a section of the feed path Z, so that in the event of a standstill of the drive device 8, the label material 4 can engage in sections with the excess material in the suction chamber 16, whereby this is caused by the negative pressure in the suction chamber 15. The forces for sucking in the label strip 4 are comparatively low due to the lightness of the material, so that the label strip 4 can be easily guided out of the suction chamber 15 even when operation is resumed.

[0046] Furthermore, as can be seen from Figure 3, the height of the opening 16 is adapted to the height of the label strip 4. Accordingly, a lower edge 17 and an upper edge 18 are provided, which can be adjusted separately from one another. A manual adjustment mechanism is provided for adjusting the lower edge 17, since adjustment of the lower edge 17 is usually not necessary, or only rarely, after initial commissioning. The adjustment is selected such that, in the event of a standstill of the label drive 8, the label strip 4 can rest on a lower surface of the suction chamber 15, which also forms the lower edge 17, without sinking significantly.

[0047] The height of the opening 16 is then adjusted primarily via the upper edge 18, with a servomotor 19 being provided for adjusting the upper edge 18. This servomotor 19 is connected to the previously mentioned control unit, allowing automated adjustment of the upper edge 18 and thus also of the opening 16 in the event of a format change.

[0048] The actuator 19 is preferably formed from an electric motor driven spindle drive, wherein an electric motor drives a spindle which causes a movement in the vertical direction V.

[0049] Figure 5 shows a situation in which the label strip 4 is sucked into the suction chamber and assumes a concave shape when viewed from the outside. The indentation E1 is relatively small; indentations E1 of less than 10 cm, preferably less than 8 cm, are intended.

[0050] The distance L1 that can be buffered on the label strip 4 is correspondingly small. With a capacity of 30,000 to 70,000 containers 3 per hour, the buffered distance L1 is 1 cm to 4 cm, and at the lower end of 30,000 containers per hour, it is even only 2 cm to 3 cm.

[0051] The label strip 4 is conveyed at a constant speed during normal, gap-free operation. This prevents loops from forming if the label drive stops. Only when one or more gaps occur in the container flow is the label strip 4 stopped and accelerated again within the machine cycle. Depending on the speed, a machine cycle typically lasts 40 to 120 ms. With consecutive gaps, the time for the label strip 4 to be stopped is a multiple of the machine cycle, whereby the label material returns to the taut state and the loop returns to its original stretched state. The length L1 is the length by which the label strip 4 would normally slacken if it were not sucked into the suction chamber 15 to maintain a certain tautness.

[0052] List of reference symbols

[0053] 1 labeling station

[0054] 2 transport carousels

[0055] 3 containers

[0056] 4 label tape

[0057] 5 roll holders

[0058] 6 supply rolls

[0059] 7 Web tension device

[0060] 8 Label drive

[0061] 9 Feeding device

[0062] 10 Cutting device

[0063] 11 Gluing device

[0064] 12 Application carousel

[0065] 13 Suction device

[0066] 14 Vacuum device

[0067] 15 Intake chamber

[0068] 16 Opening

[0069] 17 lower edge

[0070] 18 upper edge

[0071] 19 Actuator

[0072] E1 indentation

[0073] L1 length

[0074] V Movement in vertical direction

[0075] Z feed line

Claims

Patent claims Labeling station (1) for a labeling machine for labeling containers (3), in particular beverage containers, with an application carousel (12) for applying labels to the containers (3) and with a feed device (9) for feeding the labels to the application carousel (12), wherein the feed device (9) has at least one label drive (8) for driving a label strip and a cutting device (10) for separating individual labels from the label strip (4), and wherein the label strip (4) is movable within the feed device (9) along a feed path (Z), characterized in that the feed device (9) has a suction device (13) with a suction chamber (15), wherein the suction chamber (15) extends along a section of the feed path (Z), wherein a buffered length (L1) by which the label strip (4) would slacken,if it were not sucked into the suction chamber (15) to maintain a certain degree of tightness, it is 1 cm to 4 cm, in particular 2 cm to 3 cm long. Labeling station (1) according to claim 1, characterized in that the suction device (13) is arranged along the feed path (Z) upstream of the label drive (8). Labeling station (1) according to claim 1 or 2, characterized in that the label drive (8) is arranged between the cutting device (10) and the suction device (13). Labeling station (1) according to one of the preceding claims, characterized in that the suction chamber (15) is connected to a vacuum device for generating a negative pressure. Labeling station (1) according to one of the preceding claims, characterized in that an opening (16) of the suction chamber (15) associated with the feed path (Z) is adjustable.

6. Labeling station (1) according to claim 5, characterized in that a lower edge (17) and / or an upper edge (18) of the opening (16) of the suction chamber (15) is adjustable with regard to its height position.

7. Labeling station (1) according to claim 6, characterized in that a servo motor (19) is provided for adjusting the upper edge (18).

8. Labeling station (1) according to claim 6 or 7, characterized in that the suction device (13) has at least one sensor for detecting the position of the upper edge (18) and / or the lower edge (17).

9. Labeling station (1) according to one of the preceding claims, characterized in that the feed device (9) has at least one supply roll holder (5) for receiving the label strip (4) wound up into a supply roll (6) and a web tensioning device (7) arranged behind the supply roll holder (5).

10. Labeling station (1) according to one of the preceding claims, characterized in that the feed device (9) has a gluing device (11) for applying a pressure-sensitive adhesive to the labels.

11. Labeling machine with a transport carousel (2) for moving the containers (3) along a transport path and at least one labeling station (1) according to one of the preceding claims, wherein the transport carousel (2) is directly adjacent to the application carousel (12) of the labeling station (1).

12. Method for operating a container treatment plant, comprising a blow-molding machine for blowing, in particular for stretch blow-molding, containers (3) from plastic preforms and a labelling machine interlocked with the blow-molding machine for labelling the containers (3) according to claim 11, characterized in that the container treatment plant has a central control which is designed to control the label drive (8) and the suction device (13) depending on the operation of the blow-molding machine in such a way that in the event of an interruption of a container flow from the blow-molding machine to the labelling machine, a supply of labels to the application carousel (12) of the labelling station (1) is interrupted and the Label strip is held at a predetermined tension by means of the suction device (13), wherein a buffered length (L1), by which the label strip (4) would slacken if it were not sucked into the suction chamber (15) to maintain a certain tautness, is 1 cm to 4 cm, in particular 2 cm to 3 cm long.

13. A method for labelling containers (3) in a labelling machine according to claim 11, wherein the containers (3) are fed to the transport carousel (2) of the labelling machine and transported along a transport direction and wherein a label strip (4) is moved along a feed path (Z), individual labels are separated from the label strip (4), glued if necessary and applied to the containers (3) via the application carousel (12).

14. The method according to claim 13, wherein the label strip (4) is continuously subjected to a negative pressure along a section of the feed path (Z) via the suction device (13).

15. Method according to claim 13 or 14, wherein in the event of a standstill of the feed device (9), the label strip (4) lies partially in the suction chamber (15) of the suction device (13).

16. Method according to one of claims 13 to 15, wherein the containers (3) are first formed from plastic preforms in a blow molding machine by blowing, in particular by stretch blow molding, wherein the blow molding machine is interlocked with the labeling machine and the containers (3) are fed to the labeling machine after blow molding.

17. The method according to claim 16, wherein in the event of an interruption of a container flow from the blow molding machine to the labeling machine, a supply of labels to the application carousel (12) of the labeling station (1) is interrupted and the label strip is held at a predetermined tension by means of the suction device (13).

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