EP1777162A1 - Printing of packages on a conveying line - Google Patents

Abstract

The printing system for cigarette packets (1) moving along a conveyor belt (3) comprises at least two ink jet printing heads (7a, 7b) in different printing positions. They can also be moved to positions for cleaning (9a, 9b) and a park position (11a, 11b). An independent claim is included for a method for printing cigarette packets moving along a conveyor belt.

Description

The present invention relates to conveyor packaging, in particular to printing cigarette packages and packages, which packages are printed by means of printhead technology. In many branches of production, especially in cigarette production, it is often necessary to apply on packaging as late as possible in the production process markings in the form of texts, codes, bar codes or the like. This is in contrast to the printing of blanks of the packaging, for example in the manufacture of the blank in the printing house, or more generally before the actual packaging of the product, for example the cigarette block. The aim of such a late printing, especially after the packaging of a cigarette block with the blank, is usually the exact reproduction of the time of manufacture but also of the manufacturing unit in the print (in plain text or encrypted form). However, other applications are conceivable, such as an individual printing of packaging parts for advertising purposes, etc.

Devices and methods for printing cigarette packages on conveyor lines are, for example, from WO 01/54 986 A1 , of the WO 02/04 297 A1 and the DE 100 04 022 A1 known. Furthermore, the DE 103 11621 A1 and the DE 102 21 837 A1 Methods and systems for identifying cigarette packages or cigarette packaging units.

Printing systems that use printhead technology, such as using inkjet printheads, may experience downtime if the nozzles on the printheads become dirty or the image does not print for other reasons Meets requirements. It can also lead to production stoppages when the color supply of such printheads has run out.

It is the object of the invention to provide a Förderstrcken-Packungsbedruckung that can be integrated into existing packaging units of the cigarette industry and allows on-line printing with high production speeds, with downtime is largely avoided.

This object is achieved by a system according to claim 1 and a method according to claim 7. The subclaims define preferred embodiments of the invention.

In the conveyor line packing printing system according to the invention at least two print heads are provided for the production of an imprint, as well as a controller for their operation and use. In other words, according to the invention, an "overcapacity" is actually already provided in normal operation. Namely, at least two print heads are provided, each of which could perform the necessary printing work basically alone. Specifically, one could also say that two printheads are present to make a single imprint, i. For example, an identical printed on different packs, although each of the printheads could apply the imprint on all packs.

Because the printheads can be used simultaneously, at least two of them have different print positions. Furthermore, separate positions may be provided in the system for the printheads that are not currently in use, namely, for example, change, maintenance and parking positions.

The system advantageously includes a print quality monitoring system downstream of the print positions, where the monitored print quality is an input to the controller. So, if print quality is not enough, you can use a motion system for the printheads that use the printheads move from the print position to another position or another (or outdated) print head to the print position to restore the required quality.

The printheads, in accordance with a preferred embodiment of the invention, may be ink-jet printheads, in particular drop-on-demand printheads, as available on the market.

In the inventive conveyor line packing printing method, the advantages are achieved by making it possible to print at least two printheads using either one or more printheads simultaneously. There is therefore a certain amount of redundancy here, which however allows the entire printing process to be carried out with a single print head, so that silent start times can be avoided.

In the basic working state, the print can be created by at least two print heads, which alternately print packs or outer packagings. In other working conditions, the imprint can also be created by only one print head. Herein, in one embodiment, a controller controls the operation and deployment of the printheads, and specifically, the print positions are followed by a print quality monitoring system, the monitored print quality being used as an input to the controller. Further, the controller may control the movement of the printheads into positions where they are deployed when not in use, particularly in change, maintenance, and park positions.

The invention may also be described as providing a printing system consisting of multiple printheads, preferably two heads, more preferably two ink jet heads. For example, each of these printheads has its own printing position, cleaning position, and parking position (which prevents the ink from drying when using inkjet printheads). The monitoring system may, in the event of a deviation from quality standards, issue a message to a downstream ejection station where appropriate packets are ejected become. Furthermore, the cleaning or renewal of the printhead can be caused, which is responsible for the lack of quality.

An assignment is achieved by the printheads always print certain packages in the sequence. With two printheads, the first printhead always prints the packages with the odd numbers, that is, the packs # 1, 3, 5, 7 ...., and the second printhead prints the "even" packs # 2, 4, 6, 8 .... Thus, the monitoring system can establish a direct association with the print quality of the two printheads.

However, the mechanics and electronics of the printheads are designed so that each printhead alone could print on all packages without reducing the production speed of the packaging machine. In the case of contamination of the nozzles or an empty ink cartridge so the other printhead can print the packages of the defective printhead. The defective printhead simultaneously travels to the cleaning station on a provided print head guide or is replaced. In this way, the production process can be maintained, even if a printhead provides poor quality. Corresponding arrangements with 3, 4 or more printheads are possible. However, these are generally only necessary if a second print head can not reach the 100% higher print speed if one print head fails. By using a three- or four-headed printing system, the increase in printing speed would be 50% and 33%, respectively. A somewhat more complicated but quite realizable leadership, mechanics and control will be necessary.

In order to make the system even easier to use, an additional printhead could be provided according to the invention, which waits in a parking position for the failure of a printhead in operation. This makes the system even more independent of fast replacement of empty or defective printheads.

Figur 1

ein Beispiel für ein erfindungsgemäßes Drucksystem mit zwei im Einsatz befindlichen Druckköpfen;

Figur 2

das System aus Figur 1 mit einem in eine Reinigungsposition weggefahrenen Druckkopfs; und

Figur 3

das System aus Figur 1 mit einem in einem in eine Parkposition weggefahrenen Druckkopfs.

The invention will be explained in more detail below with reference to an embodiment and with the aid of the accompanying drawings. It may have all the features described herein individually or in any combination. In the drawings show:

FIG. 1

an example of a printing system according to the invention with two printheads in use;

FIG. 2

the system of Figure 1 with a printhead moved away to a cleaning position; and

FIG. 3

the system of Figure 1 with a in a parked in a parking position printhead.

FIG. 1 schematically shows a printing system according to the invention. Shown is from above a conveyor belt 3, are promoted on the cigarette packs 1 in the arrow direction. Further, Fig. 1, as well as Figs. 2 and 3, respectively show printing positions 7a and 7b for two ink jet printing heads 5a and 5b, cleaning positions 9a, 9b and parking positions 11a and 11b for the printing heads 5a, 5b.

In Figure 1, the normal operating condition, i. the printing system shown under normal production conditions. The individual cigarette packs 1 are transported on the conveyor belt 3, and they can stand on the narrow side or on any other side. If necessary, they are laterally supported by bands or rails (not shown). The two print heads 5a, 5b are shown in their printing position 7a, 7b; the respective position with the print head is filled in black.

While the packs 1 are transported by the conveyor belt 3 under the print heads 5a, 5b in the direction of the arrow, write the printheads 5a, 5b on the respective intended for them packs. This is shown schematically by the letters a and b on the packages. The choice of different letters does not mean that the imprint differs, only the assignment to the print head 5a or 5b is symbolized. In this normal operating state, the cleaning positions 9a, 9b and the parking positions 11a and 11b are not occupied.

FIG. 2 now shows the state when a printhead fails, namely when the printhead 5a fails. For example, if the nozzles of the printhead 5a are clogged, this will translate into a reduced print quality for the packs labeled a in Figure 1. A monitoring unit 2 recognizes the reduced print quality and forwards it to a controller for a print head guide system, both of which are not shown for the sake of clarity. However, FIG. 2 shows the state which occurs when the print head guidance system has moved the print head 5a out of the print position 7a into the cleaning position 9a. In this state, the print head 5b takes over the task of the defective print head; he works twice as fast and each of the packages is now labeled by the printhead 5b; she carries the mark marked b. In position 9a, the print head 5a is cleaned, after which it can be returned to its place of use 7a.

Fig. 3 shows a state where an ink cartridge of the print head 5b is empty. Here, the print head 5b is moved to the parking position 11b where the cartridge can be changed, and this time the print head 5a takes over the task of the empty print head 5b; he works twice as fast and marks all packs, as indicated by the letter a on each labeled pack. After the replacement of the empty cartridge, the printhead 5b also returns to its printing position 7b and the condition of Fig. 1, i. the normal operating state is restored.

Claims (13)

Conveyor-line packing printing system, in particular for printing cigarette packs and outer packaging, in which the packages (1) are printed by means of printhead technology, characterized in that at least two print heads (7a, 7b) are provided for producing an imprint, and a controller for the latter Operation and use. System according to claim 1, characterized in that at least two printing heads (7a, 7b) have different printing positions. System according to claim 1 or 2, characterized in that for the print heads (7a, 7b)
Positions are placed in which they are introduced when they are not in use. System according to claim 3, characterized in that the positions include change, maintenance and parking positions. A system according to any one of claims 1 to 4, characterized in that it comprises a print quality monitoring system downstream of the print positions, the monitored print quality being an input to the controller. System according to one of claims 1 to 5, characterized in that the print heads are ink jet print heads. Conveyor-line packing printing method, in particular for printing cigarette packages and outer packaging, in which the packages (1) are printed by means of printhead technology and in which a print of at least two Printheads (7a, 7b) can be made using either a printhead or multiple printheads (7a, 7b) are used simultaneously. Method according to Claim 7, in which, in the basic operating state, the print is produced by at least two print heads (7a, 7b) which print alternately packs or outer packagings (1). Method according to Claim 8, in which the imprint of only one print head is created in other working states. Method according to one of claims 7 to 9, wherein a controller controls the operation and the use of the print heads (7a, 7b). The method of claim 10, wherein a print quality monitoring system is downstream of the print positions, wherein the monitored print quality is used as an input to the controller. A method according to claim 10 or 11, wherein the controller controls the movement of the printheads (7a, 7b) to positions where they are placed when not in use, especially in change, maintenance and parking positions. Method according to one of claims 7 to 12, wherein a replacement print head is provided separately, which is placed in the place of a printhead to be replaced.

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