DEVICE AND METHOD FOR APPLYING A SLEEVE LABEL

Abstract

A device for applying sleeve labels on objects which are moving continuously along a predetermined trajectory on a transport mechanism, having an ejection unit, a detection unit, a memory unit and a control unit. The ejection unit ejects sleeve labels, and the detection unit detects objects moving on the transport mechanism and issues a detection signal that specifies a position of the object at least one point in time. The control unit controls the ejection unit and triggers the ejection of a sleeve label depending on the detection signal and a control parameter stored in the memory unit, wherein a position at which the object is located at the start of the ejection process can be changed by changing the control parameter. A camera an image sequence, which shows the ejection of the sleeve label, at a first image rate, and a user interface replays the image sequence at a second image rate that is slower than the first image rate, and receives a user input which initiates a change of the control parameter stored in the memory unit.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to German patent application 10 2013 208 355.6, filed Mar. 7, 2013. The priority application, DE 10 2013 208 355.6, is hereby incorporated by reference.

FIELD OF THE DISCLOSURE

The present disclosure relates to a device and a method for applying sleeve labels.

BACKGROUND

Devices for providing sleeve labels (also called sleeves) are used in labelling machines, for example in the beverage industry. Here, the sleeve labels are initially in the shape of a continuous tube rolled up on a roller. The tube is unrolled from the roller, supplied to a spreader mandrel and pulled over the spreader mandrel in order to open out the still flat label tube. Individual label sleeves are cut off from the typically tubular label tube, and in the further course applied onto a container, for example a bottle, by means of a servo-controlled drive roller, and then shrunk on or fastened using another means.

A device for unfolding a foil tube and cutting off foil sleeves is known from the document DE 201 04 972 U1. Foil sleeves are provided by means of an unfolding mandrel, over which a flat folded foil tube is pulled, and then opened out in the radial direction, and a cutting mechanism arranged in the lower end region of the unfolding mandrel for circumferential cutting through the unfolded foil tube from the radial outside. The cut off foil sleeves are ejected from the device by means of a drive roller and placed over the object to be labelled. Similar devices are also known from the documents EP 0 109 105 A1, EP 1 396 433 A1 and WO 2008/088210 A1.

SUMMARY OF THE DISCLOSURE

FIG. 1 schematically shows the design of a generic device 200 for applying sleeve labels 110 onto bottles 100. A foil tube 105 is pulled from the supply roll 210 over an unfolding mandrel 220 by means of drive rollers 230, 250. Suitable sections 110 of the foil tube 105 are cut off by means of the cutting mechanisms 240, and made available in the lower region of the unfolding mandrel 220. The bottles 100 are transported below the device 200 using a transport mechanism 400, for instance a conveyor belt. Here, the bottles are moved past the device continuously and with a substantially uniform speed along a predefined trajectory. The position of a bottle to be labelled, or the time at which the bottle to be labelled arrives at a predetermined position, is detected by a position sensor 300, for instance a light barrier. Drive rollers 250 are controlled depending on the detected signal in order to eject the cut sleeve label 110 so that the sleeve is placed over the bottle 100. A control unit 500, for instance a programmable logic controller (PLC), coordinates the drive rollers 230, 250, the cutting mechanism 240 and the detecting unit 300. The programs and the control parameters necessary for the control can be stored in a memory unit 510 of the PLC.

With the application of the sleeve labels onto the objects to be labelled, which typically are transported past the labelling device at high speed, there is however the problem that the time at which the label is ejected must be synchronized very precisely to the movement of the object to be labelled. This problem can be solved in that the objects are detected, for instance with the aid of a light barrier, shortly before reaching the labelling device, and the time at which the sleeve label is ejected is controlled using a suitable delay.

The FIGS. 2A and 2B correspond to the lower half of FIG. 1 and as examples show two schematic snapshots of the label transfer process. FIG. 2A shows a snapshot of the label transfer process shortly before triggering the ejection, at which the position of a bottle to be labelled is detected by a detection unit 300, for example a light barrier. The detection unit 300 is arranged at a defined position with respect to the ejection device 200 on the transport mechanism 400. At a specific time t1, a bottle is detected at location x of the detection unit. Using the known transport speed v, a delay Δt can be determined after which the bottle is located at a position that is optimal for applying the sleeve label, i.e. triggering the ejection process. According to this, the detection process is triggered at time t2=t1+Δt. Because sleeve label is ejected with finite speed, the optimal position does not necessarily coincide with the symmetry axis of the ejection device. FIG. 2B shows a snapshot of the label transfer process shortly after triggering the ejection, in which the sleeve label 110 has not yet reached the final position thereof.

At high transport speeds and/or with long tube sections, the window of time in which the ejection of the sleeve label must be started, or respectively the region in which the object must be located at this moment, is very small. For this reason, the start time t2 for the label transfer (depending on the transport speed) must be manually adjusted very precisely. This is particularly problematic at high transport speeds because, among other reasons, it cannot be detected whether the transfer of the sleeve label has occurred too early or too late such that it is not clear in which direction a correction is to be made.

Therefore the problem of the present disclosure is to specify a method and a device that simplifies an adjustment of the label transfer time.

The particular approach of the present disclosure is to record an image sequence, which shows the ejection of a sleeve label, to replay the image sequence in slow motion, and to correspondingly correct the ejection time as a result of user input.

According to a first aspect of the present disclosure, a device is provided for applying sleeve labels on objects, which are moved continuously along a predetermined trajectory on a transport mechanism. The device comprises an ejection unit, which is configured to eject a sleeve label, a detection unit which is configured to detect objects moved on the transport mechanism and to issue a detection signal that specifies a position of the object at at least one point in time, a memory unit for storing a control parameter, and a control unit which is configured to control the ejection unit and depending on the detection signal and the stored control parameter to trigger the ejection of a sleeve label, wherein a position at which the object is located at the start of the ejection process can be changed by changing the control parameter. The device is characterized by a camera mechanism that is configured for the purpose of recording an image sequence, which shows the ejection of the sleeve label, at a first image rate, and a user interface that is configured for the purpose of replaying the image sequence at a second image rate that is slower than the first image rate, and to receive a user input which initiates a change of the control parameter stored in the memory unit.

In a preferred embodiment, the detection unit comprises a proximity switch and the detection signal is a time signal that specifies a first point in time at which the object is moved past the detection unit. Here, the control parameter advantageously specifies a delay. A second point in time, at which the sleeve label is ejected by the ejection unit, can be changed relative to the first point in time, by changing the control parameter.

In a preferred embodiment, the user interface comprises a first input element that is configured for the purpose of changing the control parameter upon actuation by the user so that the first point in time is shifted earlier in time relative to the second parameter by a predetermined amount. The user interface can further comprise a second input element that is configured for the purpose of changing the control parameter upon actuation by the user so that the first point in time is shifted later in time relative to the second parameter by a predetermined amount. In this manner an intuitive adjustment of the optimal label transfer time is possible.

In a preferred embodiment, the detection unit is a position detector and the detection signal is a position signal that specifies the position of the object at a specific point in time. The control parameter can specify a target position, and the control unit can be configured for the purpose of triggering the ejection of the sleeve label when the object has attained the target position. Depending on the concrete requirements and the conditions, the use of a position detector instead of (or in addition to) a proximity switch can be advantageous.

In this case, the user interface can also comprise a first input element and a second input element in order to allow an intuitive adjustment of the optimal label transfer time. The first input element is configured for the purpose of changing the control parameter upon actuation by the user so that the target position is shifted forward by a predetermined amount in the transport direction. The second input element is configured for the purpose of changing the control parameter upon actuation by the user so that the target position is shifted backward by a predetermined amount in the transport direction.

In a particularly preferred embodiment, the detection unit is configured for the purpose of detecting a position and a speed of the object on the transport mechanism. The detection signal then specifies the position and the speed of the object at a specific point in time. In this manner the control unit can consider both the instantaneous position of the object as well as instantaneous speed thereof for controlling the label transfer time, whereby improved accuracy and reduced susceptibility to speed fluctuations can be attained. In addition, the optimal label transfer time can be guaranteed also for different transport speeds.

The memory unit is preferably further configured for the purpose of storing a plurality of control parameters in conjunction with a respective speed value. Furthermore, the control unit can be configured to read out a control parameter value from the memory unit depending on the detected speed, to trigger the ejection of a sleeve label based on the detection signal and the read out control parameter value, to change the read out control parameter value based on the user input and to store the changed control parameter value again in the control unit. Thereby, the optimal label transfer times can be guaranteed also for different transport speeds even when this cannot be determined by simple extrapolation.

Advantageously the user interface is further configured for the purpose of replaying the image sequence in the form of a repeating loop. Preferably, the user interface is further configured to update the image sequence continuously at predetermined intervals, or after each change of the control parameter. An advantageous design of the user interface is further configured to replay alternating a first image sequence, which was recorded before a change of the control parameters, and a second image sequence, which was recorded after a change of the control parameters, or to replay at the same time in two separate sections of a display region. In this way, a service person can carefully study both the present settings for controlling the transfer point, or the transfer location, as well as the effects of the last change to the settings, and thus quickly and simply attain an optimal setting.

According to a second aspect of the present invention, a method is available for applying sleeve labels on objects, which are moved continuously along a predetermined trajectory on a transport mechanism. The method comprises the following steps: detecting an object moving on the transport mechanism and generating a detection signal that specifies a position of the object at at least one point in time, storing a control parameter, and controlling an ejection unit that is configured for the purpose of ejecting a sleeve label, in order to trigger the ejection of a sleeve label depending on the detection signal and the stored control parameter, wherein a position at which the object is located at the start of the ejection process can be changed by changing the control parameter. The method includes by recording an image sequence, which shows the ejection of the sleeve label at a first image rate, replaying the image sequence at a second image rate, which is slower than the first image rate, and changing the control parameters stored in the memory unit as a result of an appropriate user input.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

The disclosure is described in the following with reference to the attached figures, in which:

FIG. 1 schematically shows the design of a generic device for applying sleeve labels on bottles,

FIG. 2A shows an example snapshot of the label transfer process in the device from FIG. 1,

FIG. 2B shows another example snapshot of the label transfer process in the device from FIG. 1,

FIG. 3 schematically shows the design of a device for applying sleeve labels according to an embodiment of the present disclosure (sectional plane A),

FIG. 4 schematically shows the lower section of the device from FIG. 3 in a sectional plane (sectional plane B) perpendicular to the drawing plane of FIG. 3

FIG. 5A schematically shows a first representation of the monitor content of an operating unit during adjustment of an optimal transfer time/location,

FIG. 5B schematically shows a second representation of the monitor content of an operating unit during adjustment of an optimal transfer time/location, and

FIG. 5C schematically shows a third representation of the monitor content of an operating unit during adjustment of an optimal transfer time/location.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 3 schematically shows the design of a device for applying sleeve labels according to one embodiment of the present disclosure. The design shown in FIG. 3 corresponds substantially to that of FIG. 1, wherein the same reference numbers designate the same components, for which renewed explanation is omitted in order to avoid unnecessary repetition. In addition to the components shown in FIG. 1, the device according to the present disclosure has an operator unit 520 and a camera unit 550.

The device comprises a detection unit 300, by use of which the position of an object 100 (e.g. a container or a bottle) can be detected on the transport mechanism 400. The detection unit 300 can be a proximity sensor or a proximity switch, by use of which the point in time at which a container to be labelled attains a predetermined position along the transport mechanism 400 can be determined. The predetermined position preferably lies shortly before the location at which the sleeve labels are transferred so that the transfer point (or the point in time at which the transfer is started) can be controlled using a suitably set delay.

The detection unit can also be a position sensor, by use of which the position of the container to be labelled can be determined continuously or at specific times. The position sensor can be designed as a camera with appropriate image processing, a displacement transducer, in the form of a laser scanner, or as a field of optical or other suitable sensors. In specific embodiments the detection unit can also be configured to detect the speed of the container to be labelled.

With the design of the detection unit as a position sensor this is preferably arranged such that the position of the container to be labelled can be monitored in the direct environment of the transfer location. Then, the control unit can trigger the transfer of the sleeve label as soon as the container has attained the optimal transfer position. The control unit can also perform an interpolation or extrapolation of several position measurements in order to further improve the accuracy of the trigger point.

The triggering of the label transfer can also be time-based, location-based, or a combination thereof. For controlling the label transfer the control unit 500 has a memory unit 510 in which the suitable control parameters are stored. Depending on how the triggering occurs, the control parameters can be delay times or target positions. The control parameters can be variable in order to be adapted to possibly changed conditions such as changed transport speeds, changed dimensions of the container and/or the sleeve labels, etc. The control unit can also contain a table in which a plurality of different control parameters are stored for different conditions (e.g. speeds), and can be accessed upon need. This is particularly advantageous when the detection unit is configured for the purpose of also detecting the speed of the container, and the optimal transfer position varies with the speed.

The control unit generates a control signal for the ejection roller 250 depending on the detection signal that is supplied by the detection unit 300, and based on the stored control parameters. The point in time at which the ejection of the sleeve label is triggered, or the position, which the container has attained at this point in time, can be influenced by changing the control parameters.

The alignment and arrangement of the camera unit can be seen more precisely in FIG. 4, which shows the lower section of FIG. 3 in a drawing plane rotated by 90° (sectional plane B in FIG. 3). Here, the transport direction of the container 100 is perpendicular to the drawing plane of FIG. 4.

As indicated in FIG. 4, the camera unit 550 is aligned so that an image sequence of the label transfer process can be recorded. The optical axis of the camera unit is preferably aligned perpendicular to the transport direction and perpendicular to the ejection direction of the sleeve label. The camera unit can have an illumination unit 560.

The camera unit is configured for the purpose of recording an image sequence that shows the process of the ejection and application of a sleeve label. The image sequence is recorded at an image rate which is adapted to the transport speed and the ejection speed. In specific embodiments, the camera unit comprises a high-speed camera which records images with a frequency greater than 50 Hz or 60 Hz, preferably at 100 Hz, 200 Hz, 500 Hz or another suitable image frequency.

The image sequence recorded by the camera unit can be replayed on the monitor 525. The replay is in slow motion, that is, with a replay image rate that is less than the recording rate. The replay rate can be slower than the image recording rate by a factor of two, five or ten. Other ratios up to a single image replay are also possible. In the slow motion representation of the label transfer, it is easy to detect whether the transfer occurs at the optimal point in time or whether a correction is necessary. In addition, it is also easy to detect in which direction a correction should be performed, i.e. whether the transfer is too early or too late.

The monitor 525 can be a component of an operator unit 520 which is directly or indirectly coupled to the control unit 500 and/or the camera unit 550. The control unit can be configured in order to control the recording of the image sequence by the camera unit, to control the replay of the image sequence on the monitor, and to receive user input via the operator unit. The monitor can also be a component of a separate replay device, e.g. of portable computer or the like, on which the recorded image sequence is replayed for analysis purposes.

The operator unit 520 can comprise an input element 527 by use of which a correction of the transfer point can be initiated. For example, an actuation of a first input element can have the result of increasing a delay value, stored in the control unit, with which the ejection of the sleeve label is controlled after actuation of a light barrier 300. A second input element can correspondingly causes a decrease of the stored delay value. In embodiments in which instead of a proximity sensor (such as a light barrier) the position of the objects 100 is detected continuously, an actuation of the first or the second input element can also cause a corresponding shift of a stored target value for the transfer position. In general, actuating the input elements causes a change of the control parameters which influences the point in time for the start position of the label transfer. The change of the control parameters can be performed by the control unit as a reaction to the user inputs received via the operator unit. The control unit can, however, also be connected to an external processing unit, e.g. via a communication network that transmits the appropriate instructions to the processing unit or performs or initiates changes to the control parameters.

After each change of the control parameters, an updated image sequence can be recorded and replayed on the monitor 525 so that the user can assess the effects of change. This assessment is facilitated particularly by a suitable before/after representation, for example by an alternating replay of the original sequence and the updated sequence, by a simultaneous replay of the two sequences in image regions arranged next to each other, or by a suitable overlay of the two sequences, etc.

The user can be additionally supported with the correct setting of the transfer point, or the starting position X for the transfer, by a suitable image representation on the monitor 525. Thus for example in a special setup mode indicated in FIG. 5A, an individual image of the sequence that was recorded precisely at the point in time of the start of the transfer process is shown. The container 100 shown in this individual image is then located directly at the actual transfer position X. The arrow keys 527 on the operator unit 520 can be used in order to change the transfer position along the transport path 400. The control parameters can be appropriately adapted after each actuation of the arrow keys, and the displayed image can be updated. An input key 528 can be provided for actuating of the new transfer position and for concluding the setup mode.

Instead of the updated individual image, however, a schematic representation of the new transfer position at the location X1 can also be shown which is indicated in FIG. 5A by the dotted container 101. In an alignment mode, the target transfer position can also be shown in a similar manner by a suitable graphic overlay 101. The arrow keys 527 can then be used in order to bring the image 100 of the actual container to coincide with the schematic representation 101.

In specific embodiments, instead of or in addition to the manual assessment and adjustment of the transfer point, or the starting position of the transfer, an image processing unit can also be provided which analyses the images recorded by the camera unit and automatically performs a possibly required correction of the transfer point or the start position. The image processing unit can be configured for the purpose of detecting the (vertical) position of the sleeve label in each individual image, and depending on the detected position to initiate a change of the transfer point, or the start position. Known optimization algorithms can be used for an iterative or successive determination of the optimal transfer point or the optimal start position. The automatically determined transfer position X2 can be displayed, if applicable, on the monitor, and can be accepted by actuating the input key 528, see FIG. 5C.

Claims

1. A device for applying sleeve labels on objects, which are moving continuously along a predetermined trajectory on a transport mechanism, comprising:

an ejection unit which is configured for the purpose of ejecting a sleeve label,

a detection unit that detects an object (100) moving on the transport mechanism, and issues a detection signal that specifies a position of the object at least one point in time,

a memory unit for storing a control parameter,

a control unit that controls the ejection unit and the ejection of a sleeve label depending on the detection signal and the stored control parameter, wherein a position at which the object is located at the start of the ejection procedure can be changed by changing the control parameter,

a camera mechanism that records an image sequence at a first image rate that shows the ejection of the sleeve label (110), and a user interface that replays the image sequence at a second image rate that is slower than the first image rate, and receives a user input which initiates a change of the control parameter stored in the memory unit.

2. The device according to claim 1, wherein the detection unit comprises a proximity switch and the detection signal is a time signal which specifies a first point in time at which the object is moving past the detection unit.

3. The device according to claim 2, wherein by changing the control parameter, a second point in time at which the sleeve label is ejected by the ejection unit, can be changed relative to the first point in time.

4. The device according to claim 3, wherein the user interface comprises a first input element that upon actuation by the user, changes the control parameter so that the first point in time is shifted earlier in time relative to the second point in time by a predetermined amount, and comprises a second input element that upon actuation by the user, changes the control parameter so that the first point in time is shifted later in time relative to the second point in time by a predetermined amount.

5. The device according to claim 1, wherein the detection unit is a position detector, and wherein the detection signal is a position signal that specifies the position of the object at a specific point in time.

6. The device according to claim 5, wherein the control parameter specifies a target position, and the control unit the ejection of the sleeve label when the object has attained the target position.

7. The device according to claim 6, wherein the user interface comprises a first input element that is configured for the purpose of changing, upon actuation by the user, changes the control parameter so that the target position is shifted forward in the transport direction by a predetermined amount, and comprises a second input element that, upon actuation by the user, changes the control parameter so that the target position is shifted backward in the transport direction by a predetermined amount.

8. The device according to claims 5, wherein the detection unit detects a position and a speed of the object on the transport mechanism, and wherein the detection signal specifies the position and the speed of the object (100) at a specific point in time.

9. The device according to claim 8, wherein the memory unit is further configured for the purpose of storing a plurality of control parameter values in conjunction with a respective speed value,

the control unit reads out a control parameter value from the memory unit depending on the detected speed, triggers the ejection of a sleeve label based on the detection signal and the read out control parameter value, changes the read out control parameter value based on the user input, and stores the changed control parameter value again in the memory unit.

10. The device according to claim 1, wherein the user interface replays the image sequence in the form of a repeating loop.

11. The device according to claim 1, wherein the user interface updates the image sequence continuously, one of in pre-determined time intervals or after each change of the control parameter.

12. The device according to claim 1, wherein the user interface replays in an alternating fashion a first image sequence, which was recorded before a change of the control parameter, and a second image sequence, which was recorded after a change of the control parameter.

13. A method for applying sleeve labels on objects, which are moving continuously along a predetermined trajectory on a transport mechanism, comprising:

detecting an object moving on the transport mechanism and generating a detection signal, which specifies a position of the object at least one point in time;

storing a control parameter;

controlling an ejection unit (200) which is configured for the purpose of ejecting a sleeve label (110), in order to trigger the ejection of a sleeve label (110) depending on the detection signal and the stored control parameter, wherein a position at which the object (100) is located at the start of the ejection process can be changed by changing the control parameter;

recording an image sequence at a first image rate which shows the ejection of the sleeve label;

replaying the image sequence at a second image rate that is slower than the first image rate; and

changing the control parameter stored in the memory unit as a result of an appropriate user input.

14. The device according to claim 1, the user interface simultaneously replaying a first image sequence, which was recorded before a change of the control parameter, and a second image sequence, which was recorded after a change of the control parameters in two separate sections of a display region.