Apparatus and method for labeling containers

Abstract

The present invention provides an apparatus and a method for applying labels to containers or packs, comprising the following steps: taking over a label from a label providing unit by means of a pallet such that a glue application surface of the label faces away from the pallet; conveying the label by means of the pallet past a glue application unit, where the glue application surface of the label has cold glue applied thereto, at least over part of its area; and, subsequently, directly transferring the glue-coated label to a container conveyed by a conveyer or to a pack conveyed by the conveyor.

Claims

1. A method for applying labels to containers or packs, comprising the following steps: taking over a label from a label providing unit by means of a pallet which is adapted to be driven such that it circulates around an axis of rotation and which is pivotable in a controlled manner about a pivot axle at which the pallet is eccentrically supported and that is displaced relative to the axis of rotation, such that a glue application surface of the label faces away from the pallet; conveying the label by means of the pallet past a glue application unit, where the glue application surface of the label has glue, including cold glue, applied thereto, at least over part of an area of the label; and subsequently, directly transferring the glue-coated label to a container or to a pack, either conveyed by a conveyor, wherein the glue application surface of the label has printed thereon a variable glue image by applying the glue to the glue application surface of the label in the form of at least one of dots and lines, and wherein the variable glue image is printed onto the glue application surface of the label according to an ink-jet method.

2. The method according to claim 1, wherein the glue application unit has cold glue supplied thereto by controlled deformation of a deformable glue reservoir.

3. The method according to claim 1, wherein the label is taken over through negative pressure by means of a plurality of suction openings of the pallet.

4. The method according to claim 3, further comprising controlled activation of a subset of the plurality of suction openings of the pallet, depending on a size and/or a shape of the label to be taken over.

5. The method according to claim 3, wherein the plurality of suction openings of the pallet is deactivated for transferring the glue-coated label to the container or the pack.

6. A labeling device for applying labels to containers or packs, comprising: a conveyor for the containers or packs; a label providing unit for providing the labels; a glue application unit for applying cold glue to the labels; and a transfer device comprising at least one pallet for taking over a label from the label providing unit and for supplying the label to the conveyor; wherein the transfer device is arranged between the label providing unit and the conveyor such that the label is taken over from the label providing unit by the at least one pallet in such a way that a glue application surface of the label faces away from the at least one pallet, and that the label conveyed by the at least one pallet is transferred directly to a container or to a pack, either conveyed by the conveyor; wherein the glue application unit is configured and arranged relative to the transfer device such that the glue application surface of the label, which is moved past the glue application unit by the at least one pallet, has glue, including cold glue, applied thereto, at least over part of its area; wherein the transfer device comprises a pallet carousel with a plurality of pallets which are adapted to be driven such that they circulate around an axis of rotation and which are pivotable in a controlled manner about pivot axles at which the pallets are eccentrically supported and that are displaced relative to the axis of rotation, wherein the glue application unit comprises a plurality of glue nozzles, which is controllable, including individually controllable, and wherein by means of the plurality of glue nozzles a variable glue image is printed onto the glue application surface of the label by applying the glue to the glue application surface of the label in the form of at least one of dots and lines, and wherein the glue application unit is configured to print the variable glue image in accordance with an ink-jet principle by applying the glue in a jet with glue drops.

7. The labeling device according to claim 6, further comprising a negative pressure supply unit, wherein the at least one pallet is configured as a vacuum pallet with a plurality of suction openings on a contacting surface of the at least one pallet for the labels to be conveyed.

8. The labeling device according to claim 7, wherein the at least one pallet is configured such that the plurality of suction openings can be supplied with negative pressure individually or in groups.

9. The labeling device according to claim 7, further comprising an open-loop and/or a closed-loop control unit configured for supplying the plurality of suction openings of the pallet with negative pressure in a controlled manner via a plurality of control valves.

10. The labeling device according to claim 7, further comprising an interrupter which is configured for interrupting a negative pressure supply of the at least one pallet when the label is applied to the containers or packs.

11. The labeling device according to claim 6, further comprising a controllable deformation unit for removing the cold glue from a deformable reservoir to be supplied to the glue application unit, where the controllable deformation unit comprises a deformation element configured to mechanically act upon the reservoir to squeeze the cold glue out of the reservoir.

12. The method according to claim 1, wherein the ink-jet method includes applying the glue in a jet with glue drops.

13. The method according to claim 4, wherein the plurality of suction openings of the pallet is deactivated for transferring the glue-coated label to the container or the pack.

14. The labeling device according to claim 7, where the negative pressure supply unit is a vacuum pump.

15. The labeling device according to claim 6, where the plurality of glue nozzles includes heatable glue nozzles.

16. The labeling device according to claim 6, further comprising an open-loop and/or closed-loop control unit having a memory unit storing glue images corresponding to a plurality of label formats.

17. The labeling device according to claim 6, where the plurality of glue nozzles is arranged at a distance from the glue application surface lying in a range from 1 mm to 2.5 mm.

18. The labeling device according to claim 6, where the plurality of glue nozzles is arranged at a distance from the glue application surface that is smaller than 1 mm.

19. The method according to claim 1, further comprising: storing glue images corresponding to a plurality of label formats in a memory unit.

20. The method according to claim 1, further comprising: changing an eccentricity of a support of the pallet at the pivot axle by means of a controllable linear actuator or at least one control cam.

21. The labeling device according to claim 6, further comprising: at least one controllable linear actuator configured to change an eccentricity of a support of the pallets at the pivot axles.

22. The labeling device according to claim 6, wherein the pallet carousel comprises at least one control cam configured to change an eccentricity of a support of the pallets at the pivot axles.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) Additional features and exemplary embodiments as well as advantages of the present invention will be explained in more detail hereinafter with reference to the drawings. It goes without saying that the embodiments do not exhaust the scope of the present invention. It also goes without saying that some or all of the features described hereinafter may also be combined with one another in other ways.

(2) FIG. 1 shows schematically a top view of a labeling device according to the present invention.

(3) FIG. 2 shows a variation of the labeling device of FIG. 1 for label tapes.

(4) FIG. 3 shows a cross-section through a schematic representation of a device for removing cold glue by deformation of a reservoir according to the present invention.

(5) FIG. 4A shows a side view of an exemplary vacuum pallet according to the present invention.

(6) FIG. 4B shows a front view of the vacuum pallet according to FIG. 4A.

(7) FIG. 5A shows a schematic cross-section of an alternative embodiment of a vacuum pallet according to the present invention.

(8) FIG. 5B shows a perspective view of the vacuum pallet according to FIG. 5A.

(9) FIG. 6 shows schematic front views of a vacuum pallet and of a glue nozzle array of a glue printer according to the present invention.

(10) FIG. 7A shows a special embodiment of a vacuum pallet with suction cups according to the present invention.

(11) FIG. 7B shows an exemplary embodiment of a suction cup with a touch valve according to the present invention.

(12) In the following, identical or similar elements are designated by identical reference numerals. These elements will not be described repeatedly for the sake of clarity. In addition, it goes without saying that in the following embodiments some of the elements or all of the elements can be replaced by or combined with similar elements described in connection with other embodiments.

DETAILED DESCRIPTION

(13) FIG. 1 shows a schematic representation of a labeling device according to the present invention in a top view. In the further development shown here, the labeling device 100 comprises a conveyor, which is configured as a container table 114 and along which the containers 113 or packs to be labeled circulate on a curved track on a plurality of holders that are rotatable about their own axis (not shown). The depicted, non-limiting further development additionally shows further frequently used elements of a labeling device. For example, a pretreating unit 112 may be provided, which prepares the container to be labeled 113 for the labeling process by cleaning and premoistening the container surface to be labeled or by subjecting said container surface to blow cleaning, a heating and/or radiation and/or plasma and/or corona treatment. In addition, sensors 109 and 110 may be provided, which measure the condition of the surface to be labeled, e.g. smooth, rough, etc., and/or ambient conditions, such as e.g. an ambient temperature or humidity, and transmit this information to the open-loop and/or closed-loop control unit 140 for controlling the labeling device. Furthermore, a roll-on unit 115 and/or a brush-on unit 116 may be provided downstream of the labeling position 118, so as to fully apply the label 120 placed onto the container and press it onto the latter. The containers provided with the label 117 are then transferred to a subsequent treatment station, e.g. a filling station for filling with a liquid foodstuff.

(14) According to the present invention, the labeling device 100 comprises a transfer device 103 with at least one pallet 104, 105, 106. In the further development shown, the transfer device 103 is configured as a pallet carousel comprising a plurality of pallets 104, 105, 106, which circulate around an axis of rotation of the pallet carousel and which, in turn, are configured such that they are pivotable about eccentrically supported pivot axles 119 of their own. The pallets have on their outwardly directed side a contacting surface 123, which may be sufficiently large for accommodating a plurality of different label formats. While circulating around the axis of rotation of the pallet carousel 103, the initially unladen pallet 104 is moved past a label magazine 101 in the form of a label box, which is arranged on the periphery of the pallet carousel, and simultaneously pivoted such that the contacting surface 123 of the pallet will take over from the label box 101 the frontmost label 102 presented with its image side. Since, as will be described hereinafter in more detail, the pallets 104, 105, 106 are configured as vacuum pallets, this transfer can reliably be carried out even without applying glue to the contacting surface 123 in advance. In order to be able to adapt the distance between the frontmost label 102 and the pallet carousel 103, the label box 101 may be configured such that it can be switched via a pneumatic cylinder 130.

(15) Since the labels 102 are provided such that their image side faces forwards, they will also come to lie with their image side on the contacting surface 123 of the pallet 105. It follows that the glue application surface 122 of the labels 107 conveyed by the pallets 105 and 106 faces away from the contacting surface of the respective pallet. The thus outwardly directed glue application surface of the label 107 can therefore have glue applied thereto directly on the pallet by means of a glue application unit 124 and 125, respectively, arranged on the circulation path of the pallets 104, 105, 106, i.e. on the circumference of the pallet carousel 103. FIG. 1 shows, as alternatives, a glue application unit 124 operating according to the ink-jet method as well as an area-type glue application unit 125.

(16) When a glue printer 108 is used, the cold glue is sprayed directly onto the glue application surface 122 in the form of a glue jet 121 from a large number of glue nozzles. To this end, the glue application surface 122 is moved past the openings of the glue nozzles preferably at a constant distance therefrom by circulating and pivoting the pallet 106. By accurately controlling the glue nozzles, e.g. according to the DoD principle (drop-on-demand), an almost arbitrary glue image can be printed onto the glue application surface 122 in superposition with the pallet movement. In particular, precisely the necessary amount of cold glue can be applied by printing, so that a glue return flow can be dispensed with completely.

(17) Alternatively, a glue application unit 125 may be used for areally applying glue to the glue application surface 122 of the label 107. As regards this glue application unit 125, FIG. 1 only shows schematically the basic components glue roller 126, glue scraper 127 and glue supply line 128. The cold glue supplied via the glue supply line 128 is applied by means of the glue scraper or glue application bar 127 to the circumferential surface of the glue roller 126, on which the glue application surface 122 of the label 107 rolls when the pallet 106 is passing by. This leads to an areal application of glue to the glue application surface. Glue supply lines, glue rollers and glue scrapers are well known in the prior art and, consequently, they will not be described in detail in the present context. Other than in the case of the glue application unit 124 operating according to the ink-jet method, it is not possible to apply an arbitrary glue image when the glue is applied areally. On the contrary, measures have to be taken for preventing an application of glue to parts of the pallet 106 which are not covered by the label 107, since this would result in contaminations and failures. In addition, a glue return flow for excess glue running down from the glue roller 126 may perhaps be required.

(18) Such a glue return flow will, however, not be necessary, when the supply of glue takes place via the glue supply line 128 in a controlled manner and in the amount required by means of one of the above described, controllable deformation units. This is indicated in FIG. 1 for the glue application unit 124, but can also be used for the glue application unit 125. An exemplary further development of the deformation unit 129 will be described hereinafter in connection with FIG. 3.

(19) Since the cold glue is applied to the outwardly directed glue application surface 122, a gripper cylinder for placing the now glue-coated labels 107 onto the containers to be labeled 113 is, other than is normally the case in the prior art, not necessary. Instead, the labels are placed directly from the pallets 104, 105, 106 onto the containers 113 moving past the labeling position 118, and are wrapped therearound by a rotary movement of the holders of the container table 114. To this end, the pallets are moved past the container surfaces and simultaneously pivoted such that, in combination with the rotary movement of the containers and their circulatory movement around the container table, the carried-along labels will be applied to the container surfaces by rolling on. As has already been mentioned, a slip-free roll-on application of the labels to the container surfaces can be accomplished by a suitable eccentric support of the curved pallets 104-106 on their respective pivot axles 119, so that the labels applied will not shift unintentionally.

(20) The circulatory movements of the pallets 104, 105, 106 and of the holders of the container table 114 may be controlled by means of controllable drives (not shown) via the open-loop and/or closed-loop control unit 140 of the labeling device 100. Likewise, the rotary movement of the holders for the containers can be controlled, e.g. via individually provided servomotors, in an open loop and/or in a closed loop mode by means of the open-loop and/or closed-loop control unit. The pivotal movements of the pallets 104, 105, 106 can be controlled in an open loop and/or in a closed loop mode by means of the open-loop and/or closed-loop control unit via suitable control cams or also via servomotors that are specially provided for this purpose. Finally, the vacuum supply and the glue nozzles can be controlled via the open-loop and/or closed-loop control unit 140 as described hereinafter. The open-loop and/or closed-loop control unit may especially be a programmable logic control unit comprising a memory unit, e.g. in the form of a flash memory, having stored therein the storage parameters, e.g. with respect to the desired glue image, required for the purpose of control.

(21) FIG. 2 shows a variation of the further development according to FIG. 1 comprising a label-tape providing unit 201. As has already been mentioned, like reference numerals designate like elements, so that a renewed description is dispensed with for the sake of clarity. According to this further development, the labels are, however, provided in the form of label tapes, instead of a label magazine, the individual labels being separated from these label tapes by means of a cutting unit.

(22) A base frame 236 has arranged thereon a feed unit 237 for feeding a label tape 238 with a plurality of labels that are not glue-coated. In the further development shown, the feed unit 237 comprises two stocking units 237a, e.g. in the form of label tape rolls, a splicing unit 237b for automatic roll exchange, deflection rollers 237c, a loop buffer 239, a track control unit 237d for guiding the label tape 238, and a conveying unit 237e including e.g. a spring-loaded drive roller for the label tape.

(23) In addition, a cutting unit 235 and a transfer cylinder 231 are provided downstream of the feed unit 237. The cutting unit 235 is shown with a rotor 235a driven by an individually controllable drive unit 235b with the desired rotational frequency. The blades (not shown) secured to the rotor 235a cut the fed label tape 238 into individual labels 232, which are then transferred to the pallets 104, 105, 106. Cutting of the label tape 238 is carried out in engagement with the mating cutting cylinder 231, which also serves as a transfer cylinder for transferring the labels 232 to the pallets 104, 105, 106. The transfer cylinder 231 is here preferably configured as a negative pressure cylinder having suction openings formed in its circumferential surface, e.g. as a so-called vacuum roll, the label tape or the labels being suctionally attracted to said vacuum roll and held thereon. The transfer cylinder 231 may be driven via an individually controllable drive unit 231a synchronously with the rotary movement of the rotor 235a. Analogously to the above-described taking over from a label box, the separated labels 232 are, also according to this further development, taken over by moving the pallets 104, 105, 106 past the transfer cylinder 231. The circulatory and pivotal movements of the pallets 104, 105, 106 are here controlled by the open-loop and/or closed-loop control unit 140 in accordance with the rotational frequency of the mating cutting cylinder 232.

(24) FIG. 3 shows a cross-section through a schematic representation of a cold-glue removing device 370 according to the present invention. When such a device is used, the removal of glue from a deformable reservoir 380 is carried out in that a deformation unit 360 acts on the reservoir, whereby the glue accommodation volume 381 of the latter is reduced. The resultant pressure in the glue squeezes the amount of glue to be removed out of an opening 383 of the reservoir.

(25) In the non-limiting embodiment shown here, the deformation of the reservoir 380 is effected in that the wall of the reservoir is directly mechanically acted upon by a deformation element 390. To this end, the deformation element 390 according to this embodiment is adapted to be moved relative to the reservoir 380 along the longitudinal direction L by means of a motor 350, which causes a spindle 351 to move, said spindle engaging a stationary complementary mating thread 352. The motor 350 may be configured for being controlled in an open-loop and/or closed-loop mode, so that this relative movement can be controlled in an open-loop and/or closed-loop mode by means of an open-loop and/or closed-loop control unit 359. In the embodiment shown in the present figure, the part of the removing device 370 holding the reservoir 380 is stationary, whereas the deformation element 390 moves relative thereto. It goes without saying that the arrangement can be modified such that, alternatively or additionally, the reservoir can be moved relative to the deformation element.

(26) The reservoir 380 has its opening 383 connected to a connection 399 of the apparatus, e.g. via a screw thread. Owing to the screw thread, an empty reservoir can thus easily be replaced by a full reservoir. Via the opening 383 and the connection 399, the squeezed-out glue is transferred to a conveying line 328, which, as has been mentioned hereinbefore, advances the glue to the glue roller. The conveying line may be provided with a control valve 342 so that the dispensed amount of glue can be controlled precisely. Furthermore, a pressure sensor 341 and/or a temperature sensor 358 may be provided, said sensors measuring the pressure and the temperature of the glue in the conveying line 328. The measured data can be transmitted to the open-loop and/or closed-loop control unit 359 and can thus be incorporated into the open-loop and/or closed-loop control of the motor 350 of the drive unit.

(27) In the embodiment shown here, the deformation element 390 is supported on a carrier 391, the deformation element and the carrier having provided between them a spring 392 which biases the deformation element against the carrier. The spring 392 shown is here arranged in an opening 393 of the deformation element 390. Furthermore, the deformation element 390 comprises a rod 394 guided in a guide 395 of the carrier 391. According to the present embodiment, the carrier 391 has arranged thereon two sensors 396 and 397, which detect a position of a projection 398 arranged on the rod 394. Depending on signals emitted by these sensors, which may e.g. be light barriers or magnetically operating sensors, a movement of the carrier 391 can be controlled such that the projection 398 will always be located between the two sensors 396 and 397. In this way, a predetermined force applied by the spring 392 to the deformation element 390 can be adjusted and, consequently, also a predetermined pressure on the glue contained in the reservoir 380. Excessive pressure, which may result in tearing of the reservoir wall, can thus be avoided effectively.

(28) By a relative displacement of the deformation element 390 along the longitudinal direction L, the surface of the deformation element, which is configured such that it resembles the shape of the upper part of the reservoir 380, can first be brought into mechanical contact with the lower part of the reservoir and then be moved into the reservoir by further displacement. In the course of this process, the reservoir will be deformed such that the lower part of its wall is pushed into the accommodation volume 381, so that a curved edge 382 of the deformed reservoir 380 will be obtained. As the displacement of the deformation element 390 continues, the wall of the reservoir will be pushed into the interior of the reservoir further and further. This has the effect that almost all the glue contained in the reservoir will gradually be squeezed out of the latter. The shape of the reservoir 380 and of the deformation element 390 can be chosen such that the number of gaps for glue which are formed during the deformation process will be as small as possible. Accordingly, a die-shaped deformation element may, as shown here, be configured with a slightly smaller cross-sectional area than that of the reservoir, so that it can be pushed into said reservoir.

(29) The wall or at least the deformable part of the wall of the reservoir 380 is formed of a material, e.g. PET, which is adapted to be deformed by the force exertable by the deformation unit 360, and has a suitable wall thickness. Different areas of the wall may consist of different materials and/or be formed with different wall thicknesses. In particular, it is desirable that, in the further development shown, the upper part of the reservoir 380, which is not to be deformed, will not deform and thus bulge, since otherwise complete emptying of the reservoir and a controlled glue pressure cannot be guaranteed. In order to stabilize the part of the wall of the reservoir 380 which is not to be deformed, the deformation unit shown here comprises a housing 356 for accommodating this part of the reservoir, said housing being brought into contact with an outer surface of the reservoir part which is not to be deformed, in such a way that it encloses this part in a sleevelike manner. The part of the reservoir wall which is in direct mechanical contact with the housing 356 is thus prevented from bulging due to the increasing pressure in the accommodation volume 381. Moreover, the housing 356 may be provided with a controllable heating and/or cooling device 355 allowing the glue contained in the accommodation volume 381 to be heated or cooled to an optimum processing temperature. The heating and/or cooling device 355 may here be controlled with due regard to the glue temperature measured by the temperature sensor 358.

(30) A large number of alternative embodiments of the removing device 370 is imaginable. For example, the deformation element 390 may be configured as a stationary element, whereas the reservoir 380 is moved by the drive unit 350. In addition, the connection 399 for the opening 383 may be arranged below the reservoir 380. It is also imaginable to configure the connection 399 and part of the conveying line 328 as part of the deformation element 390, the conveying line 328 comprising, in the case of a moving deformation element 390, preferably at least one flexible part. The shape and the nature of the deformation unit 360 may additionally be adapted to the possible shapes of the reservoir.

(31) FIG. 4A shows a side view of an exemplary vacuum pallet 404 according to the present invention. FIG. 4B shows the associated front view of the pallet. According to this non-limiting further development, the pallet shown is supported eccentrically such that it is pivotable about a pivot axle 419. In addition, the vacuum pallet 404 shown is provided with a vacuum pad 461 consisting of a porous sintered plastic material, such as polytetrafluoroethylene (PTFE) or hard polyethylene (high-density polyethyleneHDPE), whose microchannels transmit the negative pressure generated by a vacuum pump 449 via a vacuum supply line 443 to the label contacting surface 423 of the vacuum pallet 404. Alternatively or additionally, a plurality of suction openings 446 may be provided in the contacting surface 423 as shown in the figures, said suction openings communicating via channels 445 with one or a plurality of main channels 447. The main channel 447 may, in turn, communicate with the vacuum supply line 443 and may thus be supplied with negative pressure. Alternatively or additionally, the main channel 447 may communicate via a compressed air supply line 444 with a compressed air supply unit 448, e.g. a pump, so that the openings 446 can have applied thereto compressed air for detaching a conveyed label. The vacuum supply lines 443 and the compressed air supply lines 444 of a plurality of pallets may here be connected via a common, or via two separate rotary distributors to the vacuum pump 449 and the compressed air supply unit 448, respectively.

(32) The vacuum pump 449 and the compressor 448 may be configured controllably in such a way that, depending on the position of the vacuum pallet 404 circulating around the pallet carousel 103, said pallet can have applied thereto negative pressure or compressed air by means of the open-loop and/or closed-loop control unit 140 of the labeling device as described above. Alternatively or additionally, control valves (not shown) may be provided in the supply lines 443 and 444, said control valves being opened and closed by the open-loop and/or closed-loop control unit 140 in a controlled manner. Likewise, in particular piezoelectrically configured control valves, which can be opened and closed individually or in groups by means of the open-loop and/or closed-loop control unit 140, may be provided in individual channels 445 for the suction openings 446. In this way, a supply of the suction openings with negative pressure adapted to the format of the labels to be conveyed can be realized, as shown e.g. on the left hand side of FIG. 6.

(33) FIG. 5A shows a schematic cross-section of an alternative embodiment of a vacuum pallet according to the present invention. In addition, this subfigure shows a cross-section of a glue application unit configured as a glue printer 508. FIG. 5B additionally shows a perspective view of the vacuum pallet 504. As has already been described more than once, the figures show a vacuum pallet 504 which is eccentrically supported on a pivot axle 519, the vacuum pallet according to the present further development having, however, a plurality of suction openings in the form of suction cups 546 on its curved outer surface. Hence, the openings of the suction cups 546 define the label contacting surface 523 which extends above the base area 566 of the pallet. By suitably configuring the suction cups such that they comprise touch valves, the suction cups which are not occupied by a label can be retracted to a passive position, as shown e.g. in FIG. 7.

(34) In the non-limiting further development shown, the suction cups 546 of the vacuum pallet 504 are groupwise connected via supply channels 545 to a vacuum distributor 562 as well as to a compressed air distributor 563. For this purpose, the supply channels have one of their ends connected to vacuum supply lines 543, whereas the opposite ends are connected to compressed air supply lines 544. The vacuum distributor 562 and/or the compressed air distributor 563 may especially be configured as rotary distributors, e.g. by providing an annular compressed air supply 564. The pallet 504 can thus be supplied with negative pressure and compressed air, respectively, along its entire circulatory movement around the pallet carousel 103. Just as in the case of the embodiment according to FIG. 4, suitable control valves, which are, however, not shown for the sake of clarity, may also be provided in this case.

(35) Subfigure 5A additionally shows a schematic cross-section of a glue application unit operating according to the ink-jet method and comprising a glue printer 508. Via a glue supply line 128, the cold glue is, in proper doses, supplied to the glue printer 508, e.g. by means of the above-described removing device, said glue printer spraying the cold glue via a large number of glue nozzles 565 directly onto the glue application surface of a label conveyed by the vacuum pallet 504. By pivoting the vacuum pallet 504 about the pivot axle 519, the glue application surface is moved past the glue nozzles 565 preferably at a constant distance d therefrom, so that by controlled activation and deactivation of the glue nozzles an almost arbitrary glue image can be applied to the label. Control of the glue nozzles can here be executed by the open-loop and/or closed-loop control unit 140.

(36) As shown on the right-hand side of FIG. 6, the glue printer 608 may comprise a plurality of rows of glue nozzles 665 which are arranged in parallel and the direction of which is oriented perpendicular to the direction of movement of the label 607 and tangentially to the contacting surface of the vacuum pallet 604. The right-hand side of the figure shows a front view of the nozzle array of the glue printer 608, whereas on the left-hand side of the figure a front view of the vacuum pallet 604 is shown.

(37) The front view of the glue printer 608 shows a large number of glue nozzles 665, which, according to the depicted, non-limiting further development, are arranged in three parallel rows. For increasing the resolution of the printed glue image, the rows may be staggered relative to one another, in that the glue nozzles of the central row are positioned in a vertical direction between the glue nozzles of the respective neighboring rows. In the present figure, the glue nozzles 665b required for applying glue to the exemplarily indicated shoulder label 607 are shown in a filled condition, whereas the non-required glue nozzles 665a are shown in an open condition. While the vacuum pallet 604 is passing by, the respective required glue nozzles 665b are activated in a controlled manner such that glue will be applied only to the glue application surface of the shoulder label 607, but not to the non-occupied contacting surface of the vacuum pallet. Depending on the dimensions of the nozzle array in a vertical direction, labels of an almost arbitrary size and shape can be coated with glue in this way.

(38) The vacuum pallet 604 shown in the left-hand part of FIG. 6 comprises, according to the present further development, a large number of suction openings 646, which are arranged in the form of a matrix and which may optionally be configured as suction cups. As has already been mentioned, control valves may be provided in the supply channels of the suction openings, the suction openings being adapted to be activated and deactivated individually or in groups by means of these control valves. It follows that only the activated suction openings have a negative pressure applied thereto during operation. In the present figure, the activated suction openings 646b are shown in a filled condition, whereas the deactivated suction openings 646a are shown in an open condition. The activation pattern shown corresponds here to the shape of the outlined shoulder label 607. By controlling the control valves via an open-loop and/or closed-loop control unit 140 of the labeling device, labels of an almost arbitrary shape can thus reliably be conveyed on the contacting surface of the vacuum pallet 604, without any unnecessary vacuum output being required. The respective activation patterns may here be stored together with the respective glue application image or images in a memory unit of the open-loop and/or closed-loop control unit after the fashion of a type management.

(39) FIG. 7A shows a special embodiment of a vacuum pallet with suction cups according to the present invention. The embodiment shown represents an alternative for controlling the suction openings via control valves by means of an open-loop and/or closed-loop control unit, in the case of which the suction openings to be activated are activated automatically on the basis of the shape of the label 707 to be taken over. To this end, the suction cups may be configured such that they are vertically adjustable relative to a base of the vacuum pallet, a spring mechanism 767 being provided such that the unladen, i.e. deactivated suction cups 746a will remain at a first, low position above the base and a vacuum line 745 connecting the suction cups, whereas the suction cups 746b, which are laden with a label 707, i.e. activated, are located at a second, higher position above the base. Activation and deactivation of the suction cups take here place automatically in that the label 707 to be taken over comes into mechanical contact with the push elements 766 of touch valves provided individually per suction cup. If, during the pivotal movement of the pallet, the push element 766 is actuated through mechanical contact with the image side of the label to be taken over, the spring 767 will push the suction cup to the second position, whereas the negative pressure prevailing in the vacuum line 745 will keep the non-activated suction cups 746a at the first position against the effect produced by the spring. The forces acting on the suction cups are exemplarily indicated in Subfigure 7A by arrows.

(40) FIG. 7B shows an exemplary embodiment of such a suction cup with a touch valve. A plurality of alternative embodiments are imaginable, e.g. through making use of a two-way valve or a three-way valve and through providing two separate negative pressure lines. In the further development shown, the suction cup, which is movable relative to the base of the pallet, is supported relative to the vacuum line 745 via a spring mechanism 767. The touch valve 766 comprises, in the simplified representation shown, a shaft-like tappet 773 having, on the lower end thereof, a plug 768, which is pressed via a second spring mechanism 772 into a complementarily shaped opening of the touch valve and which thus closes said opening. Moreover, in the closed condition of the touch valve, the push element 766 projects beyond the plane of the actual suction cup 774, so that a mechanical contact with a label 707 will apply a force along the longitudinal axis of the tappet 773. In the non-limiting further development shown, the channel of the suction cup is provided with an opening 771 located on the circumferential side and closed, in the deactivated condition, by a pin 769 fixed to the tappet 773. Hence, the deactivated suction cup has applied thereto a force, which results from the difference between atmospheric pressure and the negative pressure in the vacuum line 745. The resultant force compresses the spring 767 to such an extent that the whole suction cup is shifted to a low position. It follows that the thus retracted suction cup will especially not come into contact with the surface of a glue roller used for areally applying glue to the label 707, so that contaminations through glue on the suction cups can be avoided.

(41) In the activated condition shown on the right-hand side of FIG. 7B, the tappet 773 has been shifted, through mechanical contact of the push element 766 with the label 707 to be taken over, against the force of the spring 772 to such an extent that the plug 768 will clear the opening of the channel of the suction cup. This has the effect that the pressure in the channel decreases, but not down to the negative pressure prevailing in the vacuum line 745, but, due to the partial clearing of the opening 771 through the pin 769, to a lower negative pressure, i.e. a negative pressure lying between the pressure of the vacuum line 745 and atmospheric pressure. This lower negative pressure will, due to the large area of the suction cup 774, suffice to hold the tappet 773 at the activated position, but the force applied to the spring mechanism 767 by said lower negative pressure will be smaller than the force applied in the closed condition. The entire suction cup is thus shifted to a second, higher position, which lies above the low position at a distance b therefrom. It follows that the mechanism shown allows an areal application of glue to the glue application surface of the transferred label 707 by means of a glue roller or a similar glue application unit, without the non-used parts of the contacting surface being contaminated with glue. In addition, a separate control of the suction openings via control valves is rendered superfluous, when individual touch valves are used.

(42) The labeling devices described allow cold glue to be directly applied, in the form of almost arbitrary glue images, to the glue application surfaces of labels of an almost arbitrary shape and size. In addition, due to direct glue application, the glue-coated labels can be placed directly by the pallets onto the containers to be labeled. A gripper cylinder, which would otherwise be necessary, is thus no longer required. Moreover, the use of the ink-jet method for applying glue to the labels allows a precise and economical glue application, whereby resources and costs will be saved.