Abstract:
The invention relates to an apparatus and a method for transporting a label strip from a self-adhesive labelling machine, which comprises a frame and at least two grooved rollers attached to the frame, to a label-devoid strip store.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is filed under 35 U.S.C. 371 as a US national phase application of PCT/EP2007/002220, having an international filing date of Mar. 14, 2007, which claims the benefit of DE 10 2006 012 756.0 having a filing date of Mar. 18, 2006, the contents of which are hereby incorporated by reference in their entirety. 
     TECHNICAL FIELD 
     The invention relates to an apparatus and a method for transporting a label strip. 
     BACKGROUND 
     There are various ways of labelling containers, such as e.g. labelling the containers around the circumference using label strips from the roll or from a label magazine, or else labelling the containers with self-adhesive labels, the latter variant mainly being used for high-quality labelling processes. By labelling with self-adhesive labels, it is possible for example to produce a so-called “no label look”. In this case, the edge regions of the label are designed to be as transparent as possible, so that only the information, but not the label per se, can be seen on the labelled container. 
     Labelling with self-adhesive labels is usually more expensive than labelling using other methods; however, this variant is increasingly gaining in popularity due to the high quality and the wide range of design options. 
     In recent years, therefore, there have been some developments to drive forward the process of high-speed labelling with self-adhesive labels. Modern labelling machines for self-adhesive labels, as known for example from US 2003121593, have an automatic splicing station for label strips in order to minimise or eliminate the downtimes of the machines when changing the label strip rolls. 
     However, one problem with such machines is the fact that, although the downtimes with regard to the label strip supply have been minimised or eliminated, the empty carrier strip has to be conveyed away and stored after the labelling process. To date, the empty carrier strip has been conveyed away and stored on a roll, as shown in EP 1619129 A1. When the label-devoid strip store—here in the form of a roll—is full, this has to be replaced. The situation is therefore obtained whereby, although the downtime of the machines with regard to the label supply has been minimised, in terms of conveying away the carrier strip it is still necessary to take account of machine downtimes when replacing the label-devoid strip store. 
     It would therefore be desirable to provide a transport apparatus for label strips and also a method, by which apparatus/method a carrier strip can be transported away quickly and reliably. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the invention, an apparatus for transporting a label strip with at least one carrier strip includes a frame; and at least two rollers attached to the frame, wherein the two rollers have grooves. According to another aspect of the invention, a method for labeling containers with a label, which is located on a carrier strip, includes feeding a carrier strip from a storage roll to a dispensing edge, transferring a label from the dispensing edge to a container being guided past the dispensing edge, and transporting the carrier strip away from the dispensing edge to a label-devoid strip store by way of a transport device having a frame and at least two rollers attached to the frame. 
     According to one preferred further development of the invention, one roller is driven by a dedicated motor. This has the advantage that the transport of the label strip, which bears against the driven roller, can take place in a very precise manner. The second roller is preferably driven indirectly via the first roller, either due to the fact that a belt, a cam belt or the like connects the two rollers, or preferably due to the fact that the two rollers make contact, so that the second roller is moved as a result of the rolling movement of the first roller against the second roller. However, it is also conceivable that each roller has its own dedicated motor, so that an even more precise application of force to the carrier strip that is to be transported away can take place. 
     The grooves in the rollers are preferably applied in the circumferential direction. At least the remaining surface is provided with a surface structure or with a coating, or consists of a material which has so high a coefficient of friction with respect to the carrier strip that trouble-free and slip-free transport of the carrier strip can take place. According to one preferred further development of the invention, one roller has a rubber coating in order to meet these requirements of slip-free transport. According to one particularly preferred further development of the invention, the other roller is made of metal, preferably steel, and has a fluted or structured surface. 
     By virtue of this combination of the contact between the two rollers, the rubber coating of one roller on the one hand and the fluted metal roller on the other hand, an optimal, trouble-free and slip-free transport of the carrier strip can take place. 
     According to one preferred further development of the invention, one roller has a scraper element, and with particular preference the two rollers each have a scraper element. Such a scraper element is preferably designed as a rake which surrounds the rollers at least over part of their circumference, with the fingers of the rake preferably being located in the grooves. These scraper elements have the advantage that any residues left on the carrier strip—such as labels that have not detached for example—will not wrap around one of the rollers and thus cause problems. By virtue of these scraper elements, the residues from the carrier strip either adhere to the latter or adhere to the scraper element, which nevertheless does not pose any problem for the further transport operation. The scraper element therefore ensures that the surface properties of the rollers are not altered by residues. As a result, this ensures trouble-free transport of the carrier strip. 
     One preferred further development of the invention has a strip guiding device which makes it possible to further convey the carrier strip downstream of the two grooved rollers. The strip guiding device may be a channel which closely guides the carrier strip and thus allows a defined discharge to the label-devoid strip store; however, it may also be a wider channel which does not closely guide the carrier strip but does prevent random movement of the carrier strip—e.g. due to static charging—when being transported away. 
     In order to prevent static charging of the carrier strip, or to reduce this at least partially, it is conceivable to arrange a device for preventing/reducing static charging in the vicinity of the transport apparatus. Such a device may be e.g. a blowing device which transports ionised air in the direction of the carrier strip and/or the strip guiding device. 
     The strip guiding device is preferably designed as a holder for a label-devoid strip store. It is conceivable for example that the label-devoid strip store is formed by a bag, into which the carrier strip is introduced by the two grooved rollers. In such a case, the strip guiding device may be designed as a bag holder, so that it performs two functions, namely on the one hand the guidance of the carrier strip and on the other hand the holding of the bag. 
     The label-devoid strip store may however also be designed in some other way, such as e.g. in the form of a large basket or a large box, in which the carrier strip is stored e.g. in meandering fashion due to the guidance of the strip guiding device. To this end, it is also conceivable that the strip guiding device is made to move in order to be able better to achieve this meandering storage by moving the strip guiding device. 
     However, it is also conceivable to store the label-devoid strip or carrier strip in another form, namely e.g. in the form of carrier strip shreds. For example, it is possible for the carrier strip to pass the rollers and the strip guiding device in the downstream direction, it then being fed to a central carrier strip disposal system, wherein said carrier strip can then be transported away both downwards (e.g. in the floor of the hall) and upwards (e.g. via a suction device). After being transported away, the strip can then be shredded. Shredding in the suction pipe and subsequent discharge to a central carrier strip disposal system is also conceivable. 
     One particularly preferred further development of the apparatus consists in that an exchangeable frame is attached downstream of the two grooved rollers, said exchangeable frame having at least two strip guiding devices. In this case, however, just one strip guiding device is actively connected to the grooved rollers at any given time. The exchangeable frame is preferably equipped with a handle which makes it possible to displace it in such a way that it is possible to change between positions in which a respective other strip guiding device is actively connected to the two grooved rollers. When using a bag or a box or the like as the label-devoid strip store, a simple changeover from one label-devoid strip store to another label-devoid strip store can take place by means of the exchangeable frame. This ensures that an almost continuous use of the labelling machine is possible with regard to the carrier strip being transported away. 
     Preferably, the exchangeable frame has for each strip guiding device at least one cutting element and/or counter-element which, upon actuation of the exchangeable frame, cooperates with the carrier strip in such a way that a severing of the latter takes place. 
     Although the apparatus is extremely reliable, it is possible to attach at least one grooved roller in a movable manner such that it can be moved away from the other grooved roller in order for example to eliminate any disruption in the form of residual labels on the scraper elements. 
     One preferred further development of the method is such that the label-devoid strip/carrier strip is transported from a dispensing edge in the direction of the device for transporting it away, wherein the grooved rollers there transport the label-devoid strip/carrier strip via the strip guiding device into the label-devoid strip store. Once a label-devoid strip store is full, the exchangeable frame is actuated so that a second strip guiding device is actively connected to the two grooved rollers and the label-devoid strip can then be transported away via a second strip guiding device into a new label-devoid strip store. It will be understood here that, the larger the label-devoid strip store, the longer the period of time for which the label-devoid strip can be transported away into the label-devoid strip store without having to change to a new label-devoid strip store. It can be seen from this inter alia that there are no restrictions with regard to the label-devoid strip store and thus any conceivable storage medium can be used. 
     One specific embodiment of the invention will be explained in more detail with reference to the following figures. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the figures: 
         FIG. 1  shows a plan view of a labelling unit for self-adhesive labels, 
         FIG. 2  shows a side view of an apparatus for transporting a label-devoid strip, 
         FIG. 3  shows an isometric view of such an apparatus, and 
         FIG. 4  shows a plan view of two grooved rollers. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows a labelling unit for self-adhesive labels, as can be attached to a labelling machine, comprising a table  30  on which two storage rolls  17  are located, each of which consists of a roll core  26  and of a carrier strip  1  wound around the latter and comprising the labels  2 . By way of example, a carrier strip  1  with a label  2  located thereon can be seen on the storage roll  17 . 
     The carrier strip  1  with the labels  2  is guided in the direction of the arrow  31  through a splicing station  22  to a label strip store  23 . Also located in the splicing station  22  is a prepared carrier strip  1 ′ on a storage roll  17 ′, which is spliced to the carrier strip  1  as soon as the storage roll  17  comes to an end. In this way, an almost continuous labelling of containers is possible. 
     The label strip store  23  serves to provide a certain stock of the carrier strip  1 ,  1 ′ so that the labelling process can continue despite the splicing operation, which usually entails a brief stoppage of the storage rolls  17 . During the splicing operation, therefore, usually no label strip is drawn from the storage rolls  17 ,  17 ′ but instead labels from the label strip store  23  are used. 
     Thereafter, the carrier strip  1  is transported in the direction of the arrow  32  to a dispensing edge  18 , where it is significantly deflected so that the labels  2  detach from the carrier strip  1  and can thus be transferred to the containers to be labelled which are not shown here). The label-free carrier strip  1  is then further conveyed in the direction of the arrow  33  to the apparatus  10 , where it is then fed to the label-devoid strip store. 
       FIG. 2  shows the apparatus  10  in a sectional view from the side. Here, the carrier strip  1  is transported downwards through the apparatus  10  from above in the direction of the arrow  34 . In this case, the apparatus  10  has a frame  3 , on which the subsequent objects are fixed or mounted. 
     It is possible to see the two grooved rollers  5  and  4 , the grooved roller  5  having a larger diameter than the grooved roller  4 . Here, the two grooved rollers  4 ,  5  are arranged with respect to one another in such a way that they make contact over part of their circumference and thus clamp the carrier strip  1  being guided past their contact surface and transport it with a force fit. In the process, they move in a direction as shown by the arrow  44 . 
     The grooved rollers  4 ,  5  are in this case surrounded by scraper elements  7 ,  7 ′ which protrude into the grooves in an extended contact area of the two rollers  4 ,  5 . The scraper elements  7 ,  7 ′ are therefore designed as rakes at least in this region. They greatly increase the functional reliability of the apparatus  10 , since disruptive influences, such as e.g. labels still located on the carrier strip  1 , are eliminated due to the fact that they are picked up or scraped off by the scraper elements  7 ,  7 ′, without winding around the grooved rollers  4 ,  5 . The scraper element  7 ′ is attached to a securing element  9  which is in turn part of the frame  3 . 
     Downstream of the grooved rollers  4 ,  5  there is an exchangeable frame  12  which has a handle  13  at one side. The exchangeable frame  12  additionally has two cutouts  20 ,  20 ′ which are each actively connected to one of the strip guiding devices  11 ,  11 ′. 
       FIG. 2  shows a situation in which the carrier strip  1  is transported by the grooved rollers  4 ,  5  downwards in the direction of the arrow  34 , through the cutout  20  and the strip guiding device  11 , into a label-devoid strip store  19  which is shown here as a bag. The label-devoid strip store  19  is attached to the holding plate  21  of the strip guiding device  11 ′ by means of a holding device (not shown here), such as e.g. a magnet, a gum, a clip or the like. The strip guiding devices  11 ,  11 ′ therefore serve here as hag holders. 
     Due to the continual transport of the carrier strip  1  into the label-devoid strip store  19 , a pressure is generated which compresses the carrier strip  1  in the store. Once the label-devoid strip store  19  is full, however, it must be changed. To this end, the exchangeable frame  12  is displaced with the aid of the handle  13  in the direction of the arrow  35 . As a result, the strip guiding device  11  is moved into the position in which the strip guiding device  11  was previously located. A filling of the label-devoid strip store  19 ′ can now take place while the label-devoid strip store  19  is replaced. 
     As a result of the displacement of the exchangeable frame  12  in the direction of the arrow  35 , at the same time the carrier strip  1  is severed by the cutting element  14  and the counter-element  24  moving past one another. When, at a later point in time, the label-devoid strip store  19 ′ is full, the exchangeable frame  12  is moved in the direction opposite the arrow  35 , so that the position of the strip guiding device  11  is once again that shown in  FIG. 2 . Before the exchangeable frame  12  can be returned to the starting position as just described, the label-devoid strip store  19  must of course be replaced. 
     Also when returning the exchangeable frame  12  to the starting position, the carrier strip  1  is severed since it is cut by the cutting element  15  and the counter-element  25 . Here, the counter-element  25  is located at the lower end of the securing element  9 . The cutting element  14  is located at the left-hand upper side of the web  50  of the exchangeable frame  12  between the two strip guiding devices  11 ,  11 ′. The cutting element  15  is located at the right-hand upper side of the web  50  of the exchangeable frame  12  between the two strip guiding devices  11 ,  11 ′, while the counter-element  24  is located on the underside of the scraper element  7 . 
       FIG. 3  shows an isometric view of the apparatus  10  from below, with the motor  6  of the roller  5  being clearly visible here. It is also possible to see the exchangeable frame  12  with the handle  13 , which is guided below the frame  3  of the apparatus  10  in two rails  27 ,  27 ′. The strip guiding device  11  is attached by screws  28  to the exchangeable frame  12 . The exchangeable frame  12  moreover has two sliding grooves  23 , by means of which a reliable displacement of the exchangeable frame  12  in the direction of the arrow  35  is ensured. 
     In order to ensure the accessibility of the two grooved rollers  4 ,  5 , a pivoting mechanism  40  is provided. For pivoting, a locking mechanism  16  is moved in the direction of the arrow  36  so that the hook  41  located at the left-hand end of the pivoting mechanism  40  can be pivoted about the rotation axis A in the direction of the arrow  37 . Since the roller  4  is mounted in this pivoting mechanism  40 , said roller is pivoted by the movement just described, as a result of which accessibility to the two rollers  4 ,  5  is ensured. 
     The pivoting-in of the roller  4  takes place by the pivoting mechanism  40  being pivoted about the rotation axis A in the direction opposite that of the arrow  37 , so that the hook  41  of the pivoting mechanism  40  latches into the cylindrical element  42  located at the end of the roller  5 . The locking mechanism  16  is then pivoted about the rotation point  38  in the direction opposite the arrow  36  and is fixed to the cylindrical element  42 . The grooved roller  4  is provided on the outer sides with an eccentric adjustment means  39  so as to be able to carry out an adjustment in the direction of the roller  5 . An optimal engagement of the two grooved rollers  4 ,  5  with regard to the contact force is ensured as a result. 
       FIG. 4  shows the two grooved rollers  4 ,  5 , which each have grooves  8  in the circumferential direction. The webs  53  of the grooved roller  5  are made of rubber, and the webs  43  of the grooved roller  4  are made of knurled metal, the knurling pattern of the roller  4  being shown in  FIG. 4 . Here, the two grooved rollers  4 ,  5  are arranged with respect to one another in such a way that the webs  53  of the roller  5  and  43  of the roller  4  make contact with a defined force, so that only one grooved roller has to be equipped with a motor  6 , since the drive of the grooved roller  4  takes place indirectly via the grooved roller  5 . Furthermore, the fact that the grooved rollers  4 ,  5  bear against one another in this way has the advantage that the carrier strip  1  is further transported with a force fit, so that it is possible to work against a pressure that builds up in the label-devoid strip store due to the stored carrier strip  1 .