EP3684620B1 - Direct printer and method for printing containers with a multiple-colour direct print - Google Patents

Description

The invention relates to a direct printing machine and a direct printing method for printing containers with a multicolored direct print according to the preamble of claim 1 or 13.

Typically, containers, such as beverage containers, are labeled in a labeling machine to identify and/or advertise the contents of the container.

Recently, however, direct printing machines and methods have increasingly been used for this purpose, with the containers being provided with direct printing according to the inkjet principle instead of or in addition to the labels. This makes it possible to individually print the containers in a container flow.

Such direct printing machines usually include a transporter for transporting the containers and a number of attached, stationary direct printing stations with direct printing heads in order to print the containers with the multicolored direct print. With the conveyor, the containers are, for example, picked up in container holders and transported to the stationary direct printing stations. At the stationary direct printing stations, the containers are each rotated by means of the container holders and are thereby printed with one printing ink from a large number of printing nozzles using one or more direct printing heads. The print nozzles are controlled in such a way that the ink drops emitted onto the container produce the desired print image. For multi-color direct printing, the containers are transported past the direct printing stations, where they are sequentially printed with different inks, such as white, cyan, magenta, yellow and black. Printing with special colors such as silver or gold is also conceivable. In addition, such direct printing machines include an ink supply system for supplying the direct printing stations with the printing inks, which includes a storage tank for each printing color at the stationary direct printing station.

A disadvantage of the known ink supply systems is that refilling the ink in the storage tanks has to be carried out frequently by an operator and is time-consuming. Furthermore, in the known ink supply systems, there is no control over operating errors by the operator, which can lead, for example, to soiling of the machine or refilling of unsuitable or expired printing ink in the reservoir can come. In addition, the printing inks in the storage tanks have to be refilled from plastic containers with a correspondingly high frequency of throughput, which results in a correspondingly high volume of plastic waste.

The DE 10 2015 215224 A1 discloses a container treatment machine and a method for printing containers.

The object of the present invention is therefore to provide a direct printing machine and a direct printing method for printing containers with direct printing, in which the ink supply system is improved with regard to the disadvantages mentioned above.

To solve this problem, the invention provides a direct printing machine with the features of claim 1. Advantageous embodiments of the invention are specified in the dependent claims.

Due to the fact that the direct printing machine includes the refilling station with a plurality of locations for exchangeable refilling tanks, the operator can introduce the exchangeable refilling tanks centrally into the location of the refilling station. As a result, the operator no longer has to fill the storage tanks at the individual direct printing stations, which saves on corresponding walking distances. The automatic pumping of the printing ink from the exchangeable refilling tanks into the storage tanks also means that the printing inks can be refilled without the operator having to intervene, resulting in further time savings. Because the replaceable refill tanks are received in the receiving locations, it is possible to mechanically check the correct assignment of the replaceable refill tanks and/or the quality of the printing ink filled in them. As a result, incorrect operation by the operator can be prevented.

The direct printing machine can be arranged in a beverage processing plant. The direct printing machine can be arranged downstream of a filling system for filling a product into the containers and/or a closing device for closing the containers with closures. However, the direct printing machine can also be installed upstream of the filling process and/or directly downstream of a container production process. Detached from this, it can also be a direct printing machine that is not assigned to any system but works in so-called stand-alone mode.

The containers can be intended to hold beverages, hygiene articles, pastes, chemical, biological and/or pharmaceutical products. In general, the containers can be provided for any free-flowing or fillable media. The containers can be made of plastic, glass and/or metal, but hybrid containers with material mixtures are also conceivable. The containers can be bottles, cans, beverage containers and/or tubes.

The conveyor can comprise a carousel and/or container receptacles arranged to run along with it. As a result, the containers can be transported in a predetermined grid and rotated relative to the direct printing station during printing. The carousel can preferably be rotated about a vertical axis by means of a drive. "Vertical" here can mean the direction that points to the center of the earth or runs in the direction of gravity. The conveyor can be designed to transport the containers intermittently or continuously. In the case of intermittent transport, the containers are briefly stopped in relation to the at least one stationary direct printing station during printing and then transported further. However, continuous transport is also conceivable, in which the containers are transported further by the transporter during the printing process.

The stationary direct print stations can each comprise one or more direct print heads in order to print one of the printing colors therewith. The stationary direct printing stations can preferably each include one of the storage tanks of the ink supply system for the respective printing color. The direct print heads can work with a digital or inkjet printing process in which the ink is delivered to the containers by means of a large number of print nozzles. "Inkjet printing process" can mean here that a sudden increase in pressure is generated in the chambers of a printing nozzle via piezoelectric or thermal elements in such a way that a small amount of printing fluid is pressed through the printing nozzle and delivered to the container as a pressure drop. The direct print heads can each have a number of print nozzles in a range from 100 to 10000, in particular in a range from 500 to 5000 nozzles. The pressure nozzles can be arranged in one or more rows of nozzles (for example 1-4), which are arranged in particular parallel to the container axis.

"Stationary" direct printing stations can mean here that the direct printing stations are arranged in a stationary manner relative to a machine base or a stand for the direct printing machine.

The ink supply system can include at least one header tank for each direct print head in order to adjust a meniscus pressure of the direct print head. This ensures a particularly high print quality. "Meniscus pressure" here can mean a pressure difference between a forward and a return at the direct print head. This can also mean an operating pressure of the printing ink in the direct print head. A distributor unit can preferably be arranged after the respective storage tank in order to distribute the printing ink to a plurality of direct print heads, preferably via the at least one header tank. This means that the direct print heads can be supplied with the same ink from the same storage tank be increased, thereby increasing the pressure area on the containers. The ink supply system can preferably include a feed and/or a return for each storage tank in order to circulate the printing ink from the corresponding storage tank through at least one of the direct print heads or to convey it to at least one of the direct print heads. This avoids sedimentation in the ink supply system. Preferably, the flow and/or the return can be divided via the distribution unit to a number of direct print heads. As a result, ink can be circulated from a supply tank through multiple direct printheads. The ink supply system can include at least one ink pump for each storage tank in order to remove the printing ink from it and to convey it to one or more of the direct print heads or back. It is conceivable that an ink pump is arranged in each case in the flow and/or in the return.

The storage tanks can have the same or a larger volume than the replaceable refill tanks in order to pump the entire contents of ink from a replaceable refill tank into one of the storage tanks at once. The storage tanks can each be provided to hold a supply of printing ink for the respective direct printing station.

The replaceable refill tanks can be designed so that an operator can couple them to the refill station, preferably with a connection for removing the printing ink. "Replaceable" can mean here that the replaceable refill tanks are designed to be removable during a printing operation of the direct printing machine, for example by being inserted into the receiving locations and/or secured by means of a quick-release fastener. Likewise, “exchangeable” can mean that the refill tanks are directly accessible to the operator from the outside during the printing operation in order to exchange them.

The direct printing machine can include a control unit for controlling the direct printing stations, the direct printing heads and/or the transporter, preferably the container receptacles arranged thereon and/or the ink supply system, or work together with it or be connected to it. The control unit can include a CPU, a screen and/or an input unit.

All receiving places can be arranged together as a unit in the refill station. Preferably, the refill station can be located separately from the direct printing stations. The receiving locations can each be designed to receive or hold one of the replaceable refill tanks. For example, the receptacles can each include a receptacle for holding one of the replaceable refill tanks.

The receiving places can be arranged adjacently in a shelf-like receiving front, preferably one above the other, next to one another or as a matrix. The receiving locations can thus be arranged in a particularly compact manner in the refilling station, so that the operator can reach them easily and quickly to exchange the refilling tanks. The fact that the "receiving places are arranged adjacently in a shelf-like receiving front" can mean here that they are arranged in a cascade-like manner in the receiving front.

The refill station can be designed as a cabinet unit that is separate from the stationary direct printing stations and the storage tanks and can be connected to it via connecting lines for the printing ink. As a result, the operator can replace the replaceable refill tanks particularly quickly at a central location. The connecting lines can each connect at least one of the replaceable refill tanks to a storage tank. The receiving front can be a front or top of the separate cabinet unit.

It is conceivable that the refilling station includes at least one additional receiving space for a supply tank with a cleaning fluid and/or for a waste tank for the printing ink. This means that the refill station can also be used for a cleaning procedure for the direct printing stations. In addition, the cleaning fluid can be refilled centrally or the waste tank can be emptied centrally. "Cleaning fluid" can mean a liquid with which the direct print heads can be cleaned. “Waste tank” can mean a container in which used printing ink can be disposed of, for example after the ink supply system has been flushed or at least one of the direct print heads has been purged.

The replaceable refill tanks can each comprise a bag for holding the printing ink and a support structure at least partially surrounding the bag, the bag having the connection for removing the printing ink, preferably the bag consisting at least partially of plastic and/or the support structure being designed as a support box . As a result, there is less plastic waste to be disposed of after the ink has been removed from the replaceable refill tanks. As used herein, "pouch" may mean a self-contained bladder to contain the ink. The connector may include a coupling element to connect the replaceable refill tank to a connecting coupling of one of the receiving locations. Preferably, the bag can be made of a liquid-tight plastic film. The support structure can be a frame structure or a box-like structure to provide mechanical stability to the bag. The supporting structure designed as a supporting box can consist of cardboard and/or a paper-like material. This creates cardboard waste that is easier to recycle instead of the plastic waste. The support structure, preferably the support box may have an opening through which the connector of the ink extraction bag protrudes to the outside. The support structure, in particular the support box, can be designed to be foldable in order to fold it together after use in a particularly space-saving manner.

The mounting locations can each include a mount for one of the replaceable refill tanks, a connection coupling for detachable connection to the received, replaceable refill tank and/or an ink pump for pumping the printing ink from the received, replaceable refill tank to one of the storage tanks. As a result, the exchangeable refill tanks can be set down particularly easily at the receiving locations and connected for automatic transfer of the printing ink. Here, a receptacle can mean a storage area, a rail and/or a tool-free attachment for one of the replaceable refill tanks. A connecting coupling can mean a connection element that can be coupled to the connection of the replaceable refill tank. This can preferably be the connection for removing the printing ink from the bag described above. The connection coupling can be designed for connecting and removing the printing ink from the accommodated, replaceable refill tank, for example as a connectable tubular element. The ink pump can be connected, on the one hand, via a first hose element to the replaceable refill tank that is accommodated, and, on the other hand, to the storage tank with a second hose element.

The receiving locations can each include a valve block arranged upstream of the ink pump, in order to selectively pump printing ink from the received, replaceable refill tank or ambient air to the storage tank. As a result, the connecting lines to the storage tank can be filled with both printing ink and the ambient air. Consequently, the ink remaining in the connecting lines after the automatic pumping can also be emptied into the storage tank in order to avoid sedimentation in the connecting lines.

The receiving locations can each include at least one display element for displaying an operating state. As a result, the operator can determine in a particularly simple and reliable manner whether the printing inks in the replaceable refill tanks are in a proper condition. It can also indicate if one of the interchangeable refill tanks needs to be replaced.

The receiving places can each have a data transmitter, preferably an RFID read/write head, and the exchangeable refill tanks can each have a data mark, preferably a Include an RFID tag to exchange and/or store preferably encrypted data about the ink present in the respective replaceable refill tank. As a result, all the data about the replaceable refill tanks or the printing inks contained in them can be stored in the data marks, so that a central database is unnecessary. In addition, the expiry date of the printing ink contained in the associated replaceable refill tank can be stored in the data tag. It is also conceivable that a point in time is stored in the data tag at which the replaceable refill tank was last shaken or must be shaken in the future. This avoids sedimentation of the printing ink in the replaceable refill tank. It is also possible with the data marks to prevent the supply of printing ink from a third-party manufacturer to the storage tanks. If the data in the data tag are encrypted, they are particularly well protected against manipulation. It is also conceivable that ink consumption of the printing inks is stored in the data marks in order to give the operator timely information about ordering new, replaceable refill tanks. The data tag and the data transmitter can preferably be designed for wireless data transmission. If the replaceable refill tanks each have an RFID tag, they do not require their own power supply and can still be read or written to wirelessly.

The receiving locations can each be designed as an exchangeable module and can be connected to the refilling station via at least one fastening element. As a result, they can be replaced particularly quickly by the operator during maintenance and/or in the event of a failure. For example, the receiving locations can be arranged on a support wall of the separate cabinet unit and connected to it via the at least one fastening element.

The receptacles can each include a carrier for the ink pump and/or the valve block and a housing at least partially surrounding the carrier with the receptacle for the replaceable refill tank, the receptacle preferably being arranged on an outside of the housing as a storage surface. As a result, the mounting locations are constructed in a particularly simple manner and are more quickly accessible for maintenance.

The control unit can be designed to control the refilling station with the receptacles, in particular the ink pump, the valve block, the display element and/or the data transmitter. The control unit can preferably be designed to encrypt the data transmitted between the data transmitter and the data tag.

In addition, the direct printing machine can comprise an exchangeable refill tank, the exchangeable refill tank comprising a bag for holding the printing ink and a support structure at least partially surrounding the bag, the bag having a connection for removing the printing ink, preferably the bag consisting at least partly of plastic and/or the support structure is designed as a support box. As a result, there is less plastic waste to be disposed of for the replaceable refill tank after the ink has been removed. The replaceable refill tank can include the features described above in this regard individually or in any combination.

Furthermore, the invention provides a direct printing method for printing containers with a multicolored direct print according to the features of claim 13 to solve the task. Advantageous embodiments of the direct printing method are specified in the dependent claims.

The fact that the exchangeable refill tanks with the printing inks are received in several receiving places of a refilling station and the printing inks are automatically pumped from one of the exchangeable refilling tanks into one of the storage tanks, the operator can first bring the exchangeable refilling tanks centrally into the refilling station at the receiving places. As a result, the operator no longer has to fill the storage tanks individually at the direct printing stations, thereby saving corresponding walking distances. Due to the automatic pumping of the printing ink from the exchangeable refilling tanks into the storage tanks, several printing inks can be refilled without intervention by the operator, resulting in further time savings for the operator. Because the replaceable refill tanks are received in the receiving locations, it is possible to check the correct assignment of the replaceable refill tanks and/or the quality of the printing ink filled in them independently of the operator. As a result, incorrect operation by the operator can be prevented.

The direct printing method can be carried out with the direct printing machine described above, preferably according to one of claims 1-11. The direct printing method can include the features described above in relation to the direct printing machine individually or in any combination.

The replaceable refill tanks can each be replaced as a whole by an operator for refilling the printing ink. This will make the refill tanks interchangeable not filled up but replaced, whereby a corresponding time saving is possible for the operator.

It is conceivable that the entire content of printing ink in an exchangeable refill tank is pumped into one of the storage tanks when required. This creates in the ink supply system particularly little sedimentation. For this purpose, the storage tanks can have the same or a larger volume than the replaceable refill tanks.

One of the refill tanks can be shaken by an operator to avoid sedimentation and the time of shaking can be stored in a data tag of the refill tank, preferably in an RFID tag. This can prevent the quality of the ink contained in the refill tank from being reduced by sedimentation. Alternatively, a future point in time for renewed shaking can also be stored in the data marker.

Figur 1

eine Ausführungsbeispiel einer erfindungsgemäßen Direktdruckmaschine zur Bedruckung von Behältern mit einem mehrfarbigen Direktdruck in einer Draufsicht;

Figur 2

die Nachfüllstation der in der Figur 1 dargestellten Direktdruckmaschine in einer perspektivischen Darstellung;

Figur 3A - 3B

einer der Aufnahmeplätze der in der Figur 2 dargestellten Nachfüllstation in zwei perspektivischen Darstellungen, mit bzw. ohne austauschbaren Nachfülltank;

Figur 4

der Aufnahmeplatz der Figur 3A - 3B in einer zerlegten, perspektivischen Darstellung; und

Figur 5

ein Ausführungsbeispiel eines erfindungsgemäßen, austauschbaren Nachfülltanks in einer Draufsicht.

Further features and advantages of the invention are explained in more detail below with reference to the exemplary embodiments illustrated in the figures. It shows:

figure 1

an embodiment of a direct printing machine according to the invention for printing containers with a multicolored direct printing in a plan view;

figure 2

the refill station in the figure 1 illustrated direct printing machine in a perspective view;

Figure 3A - 3B

one of the recording places in the figure 2 Refill station shown in two perspective views, with and without an interchangeable refill tank;

figure 4

the recording place of Figure 3A - 3B in a disassembled perspective view; and

figure 5

an embodiment of an inventive, replaceable refill tanks in a plan view.

In the figure 1 an embodiment of a direct printing machine 1 according to the invention for printing containers 2 with a multicolored direct printing is shown in a plan view. It can be seen that the containers 2, for example coming from a filler and a closer, are transferred to the conveyor 3 with the infeed star wheel 8 and are received in the container receptacles 4 there. Taken up in this way, they are transported by the transporter 3 past the attached, stationary direct printing stations _5W , _5C , _5M , _5Y , _5S , _5K and each printed with different printing colors by means of the direct printing heads 52, here for example with white, cyan, Magenta, yellow, a special color (e.g. silver) and black. Together, these result in a multicolored direct print on the containers 2. Below the multicolored direct print applied to the containers is cured with the curing station 7 and thereby permanently stabilized, for example by means of UV light. The finished printed containers 2 are then transferred to the discharge star wheel 9 and forwarded to subsequent treatment stations, for example to a packaging machine. A control unit 10 can also be seen, with which the direct printing machine 1 is controlled via control lines that are not shown here.

The transporter 3 is designed as a carousel, for example, which rotates about the vertical axis A in the transport direction T, but a linear transporter is also conceivable. The container receptacles 4 arranged on the conveyor 3 each comprise a turntable and a centering bell, so that the containers 2 are rotated about their longitudinal axes during the printing process relative to the respective stationary direct printing station 5 _W , 5 _C , 5 _M , 5 _Y , 5 _S , 5 _K can. This allows a flat direct print to be generated.

It can also be seen that the direct printing stations 5 _W , 5 _C , 5 _M , 5 _Y , 5 _S , 5 _K each have a storage tank 51 of the ink supply system and a plurality of associated direct print heads 52, in this exemplary embodiment three direct print heads 52, for example. However, it is also conceivable only one, two or even more direct print heads 52 per direct print station 5 _W , 5 _C , 5 _M , 5 _Y , 5 _S , 5 _K . By using several direct print heads 52, the print area on the containers that can be printed on simultaneously can be increased. The respective storage tank 51 contains a supply of printing ink for supplying the direct print head 52, which is connected to it via ink lines. For example, the storage tank 51 of the direct printing station 5 _W contains an ink supply with white printing ink for the direct print heads 52. The other storage tanks 51 accordingly contain the Direct printing stations 5 _W , 5 _C , 5 _M , 5 _Y , 5 _S , 5 _K a supply of the printing colors cyan, magenta, yellow, the spot color and black to supply the direct print heads 52.

The direct print heads 52 each include at least one row of nozzles with print nozzles that work according to the inkjet principle. This makes it possible to apply pressure drops to the containers 2 in a grid and thus to generate a flat direct print together with the rotary movement of the containers 2 about their longitudinal axes. In addition, the printed inks are superimposed on the containers 2 to form a multicolored direct print.

The ink supply system comprises a distribution unit arranged in each of the direct printing stations 5 _W , 5 _C , 5 _M , 5 _Y , 5 _S , 5 _K in order to divide the printing ink from the storage tank 51 in a forward flow and optionally a return flow to the direct print heads 52. In addition, the ink supply system includes each between the storage tank 51 and the associated Direct print head 52 at least one header tank, not shown here, to ensure an operating pressure of the associated direct print head.

The refilling station 6 can also be seen, with which the storage tanks 51 can in turn be supplied with the respective printing ink. For this purpose, the refilling station includes several receptacles 630 _W , 630 _C , 630 _M , 630 _Y , 630 _S , 630 _K for the exchangeable refill tanks 631 _W , 631 _C , 631 _M , 631 _Y , 631 _S , 631 _K , each for automatic transfer of ink from the replenishing tanks into the respective supply tanks 51 are formed.

It can also be seen that the refill station 6 is designed as a separate cabinet unit from the stationary direct printing station 5 _W , 5 _C , 5 _M , 5 _Y , 5 _S , 5 _K and the storage tanks 51 and is connected to it via connecting lines for the printing inks. In addition, the receiving spaces 630 _W , 630 _C , 630 _M , 630 _Y , 630 _S , 630 _K are arranged adjacent to one another in the shelf-like receiving front 610 , which is described below in relation to FIG figure 2 is explained in more detail. This makes it possible for the operator to manage the ink supply centrally at the refill station 6 by exchanging the refill tanks _631W , _631C , _631M , _631Y , _631S , _631K . This enables the ink supply to be refilled safely and quickly.

In addition, it can be seen that the refilling station 6 comprises two further accommodation locations 650, 660 for a supply tank with cleaning fluid and for a waste tank for the printing ink. As a result, the measures required for cleaning the direct printing machine 1 can also be carried out centrally at the refill station 6 .

Below is the refill station 6 based on the Figures 2-4 explained in more detail.

In the figure 2 is an embodiment of the refill station 6 from figure 1 shown in a perspective view. It can be seen that the refilling station 6 comprises several adjacent receiving locations _630W , _630C , _630M , _630Y , _630S , _630K for the replaceable refilling tanks _631W , _631C , _631M , _631Y , _631S , _631K , which are arranged like a shelf in the receiving front 610 as a matrix. In this exemplary embodiment, there are three receiving locations each for the six printing colors white, cyan, magenta, yellow, the special color and black, which are arranged in the 6×3 matrix. In addition, in the figure 2 to see that the refill station 6 as of the in the figure 1 shown stationary direct printing station 5 _W , 5 _C , 5 _M , 5 _Y , 5 _S , 5 _K and the storage tanks 51 separate cabinet unit is formed.

The receptacles 630 _W , 630 _C , 630 _M , 630 _Y , 630 _S , 630 _K or the interchangeable refill tanks 631 _W , 631 _C , 631 _M , 631 _Y , 631 _S , 631 _K have the same structure and are expanding below using the Figures 3A, 3B and 4 and 5 explained in more detail. The refill tanks 631 _W , 631 _C , 631 _M , 631 _Y , 631 _S , 631 _K do not differ as such but only in the printing ink filled in them.

Furthermore, in the figure 2 it can be seen that the refilling station 6 comprises two further accommodation locations 650, 660 for a supply tank with a cleaning fluid and for a waste tank for the printing ink. As a result, the direct printing machine 1 can be supplied with the cleaning liquid during cleaning and the waste of printing ink can be excreted in the waste tank. Consequently, the operator can also exchange the supply tank and the waste tank centrally at the refilling station 6 .

In the Figures 3A - 3B is one of the recording places 630 in the figure 2 Refill station 6 shown in two perspective views, shown with and without a replaceable refill tank 631.

It can be seen that the replaceable refill tank 631 is placed in the receptacle 632 of the receptacle 630 . The replaceable refill tank 631 includes a connection 631a, which is connected via the connecting coupling 633 to the receiving space 630 for removing the printing ink. The connection coupling 633 is in turn via the ink line 634 with the below in the figure 4 shown valve block 639 and the ink pump 638 connected to the printing ink in the 1 to pump the reservoir 51 shown. It can also be seen that the receiving space 630 includes the display element 635 in order to display the operating status to the operator. If the display element 635 lights up green, the receptacle 630 is in a proper state and there is a sufficient supply of ink in the exchangeable refill tank 631 that has been accommodated. If, on the other hand, the display element 635 lights up red, the operator has to intervene. As a result, the operator at the refilling station 6 can see at a glance whether all the receptacles 630 are in a proper condition or whether the corresponding refilling tank 631 needs to be replaced or shaken.

In addition, the latching element 636 can be seen, to which the connection coupling 633 can be coupled if there is no replaceable refill tank 631 on the receptacle 632 . This prevents ink from flowing out unintentionally.

Furthermore, it can be seen that a data transmitter 637 is arranged on the rear side of the receiving space 630, which is embodied here, for example, as an RFID read/write head. This means that from one on the rear side of the replaceable refill tank 631 arranged data mark 631d (only in the figure 5 shown), here for example an RFID tag, encrypted data about the ink present in the replaceable refill tank 631 can be read out and/or stored therein.

For example, it is possible with the data transmitter 637 and the data tag to store an expiry date for the printing ink and, if this is exceeded, to display a corresponding operating state with the display element 635. It is also possible to store the quantity of printing ink that has already been removed from the replaceable refilling tank 631 in the data tag in order to warn the operator in good time of an empty tank or to have printing ink reordered. In addition, it is possible to store in the data tag a shaking date on which the replaceable refill tank 631 was last shaken. In this way, the operator can be shown in the future when the replaceable refill tank 631 needs to be shaken in order to avoid sedimentation. It is also conceivable that a coding is stored in the data stamp, so that printing ink authorized exclusively by the manufacturer of the direct printing machine 1 is used.

Furthermore, in the Figures 3A - 3B It can be seen that the receiving space 630 is designed as an exchangeable module and is connected to the refilling station 6 via the fastening elements 8 (in this case screws). These can be easily released so that the receiving space 630 can be easily removed from the refill station 6 in the event of a fault or maintenance.

The internal structure of the recording space 630 is based on the figure 4 explained in more detail. It is a perspective view of the disassembled receiving space 630 from FIG Figure 3A - 3B shown.

It can be seen that the receiving space 630 comprises the carrier 642 and the housing 643, which can be slid into one another and connected to one another via screws. This allows the receiving space 630 to be easily opened for maintenance or repairs. Furthermore, the valve block 639 can be seen in detail, which is connected via the connection 639a and the ink line 634 to the connecting coupling 633 for removing printing ink from the replaceable refill tank 631. On the other hand, it can be seen that the valve block 639 has an intake port 639b for ambient air. Thus, with the valve block 639, it is possible to selectively connect the intermediate pipe 640 to the replaceable refill tank 631 or to the ambient air intake port 639b.

The intermediate line 640 is in turn connected to the ink pump 638, through which the printing ink or the ambient air is conveyed into the connecting line 641.

In a refill operation, the ink pump 638 is first connected to the replaceable refill tank 631 via the valve block 639 and the connecting coupling 633 . This allows the ink automatically from the replaceable refill tank 631 in the 1 storage tank 51 shown are pumped. Subsequently, in an emptying operation, the valve block 639 is switched over to the intake opening 639b, the ambient air is sucked in via this and pumped into the connecting line 641 up to the storage tank 51. As a result, the printing ink is largely removed from the connecting line 641, so that sedimentation is prevented.

It can also be seen that the ink pump 638 and the valve block 639 are attached to the carrier 642, which can be pushed into the housing 643 and screwed to it. The housing 643 has the receptacle 632 for the replaceable refill tank 631 on the upper side. In addition, the opening 644 for the rear arrangement of the Figure 3B data transmitter 634 shown. As a result, the wireless transmission of the data and the inductive power supply by the data transmitter 637 are disturbed as little as possible.

In the figure 5 an exemplary embodiment of a replaceable refill tank 631 according to the invention is shown in a plan view. It can be seen that the replaceable refill tank 631 includes the bag 631b for holding the ink and a support structure 631c surrounding the bag 631b. The bag 631b consists here of plastic film and the support structure 631c is designed as a support box made of cardboard. The support structure 631c will give the bag 631b the necessary stability. In addition, the connection 631a can be seen, via which the printing ink D can be removed from the bag 631b. For this purpose, the connection 631a is routed to the outside through the opening 631e of the support structure 631c.

The hybrid construction of the replaceable refill tank 631 from the bag 631b and the supporting structure 631c avoids a high volume of waste in the form of plastic, so that it can be recycled more easily. Since the support structure 631c is made of cardboard as a support box, it can be recycled in a particularly environmentally friendly manner.

The direct printing machine 1 with the transporter 3, the attached stationary direct printing stations 5 _W , 5 _C , 5 _M , 5 _Y , 5 _S , 5 _K , the ink supply system, the refill station 6 and the replaceable refill tank 631 from the Figures 1-5 is used as follows:

The containers 2 are transported with _the conveyor 3 to the attached stationary direct printing stations 5W, _5C , _5M , _5Y , _5S , _5K . Here, the containers 2 are rotated about their longitudinal axes by means of the container receptacles 4 and are thereby printed with a multicolor direct print by the direct print heads 52 arranged in the stationary direct printing stations 5 _W , 5 _C , 5 _M , 5 _Y , 5 _S , 5 _K . For this purpose, the direct printing stations _5W , _5C , _5M , _5Y , _5S , _5K are supplied by the ink supply system with a plurality of printing inks from a storage tank 51 each. For refilling, an operator places the replaceable refill tanks 631 _W , 631 _C , 631 _M , 631 _Y , 631 _S , 631 _K with the appropriate printing inks in the receptacles 630 _W , 630 _C , 630 _M , 630 _Y , 630 _S , 630 _K of the refill station 6, whereupon the automatic transfer of the printing inks from the replaceable refill tanks 631 _W , 631 _C , 631 _M , 631 _Y , 631 _S , 631 _K to the respectively associated storage tanks 51 is started if required. The entire content of printing ink in an exchangeable refill tank _631W , _631C , _631M , _631Y , _631S , _631K is preferably pumped into the associated storage tank 51 so that there is as little sedimentation as possible.

It is also conceivable that the replaceable refill tanks 631 _W , 631 _C , 631 _M , 631 _Y , 631 _S , 631 _K are shaken by an operator at regular intervals to avoid sedimentation and the time of shaking is stored in the respective data mark 631d. This ensures consistent quality of the printing ink.

For refilling the ink, the replaceable refilling tanks _631W , _631C , _631M , _631Y , _631S , _631K are replaced as a whole by the operator, respectively.

Overall, it is possible with the direct printing machine 1 according to the invention or the direct printing method to refill the printing ink particularly easily and quickly, with a consistently high quality of the direct printing being ensured. In addition, the replaceable refill tank of the present invention creates less plastic waste that is difficult to recycle.

Claims (16)

1. A direct printing machine (1) for printing containers with multicolour direct printing, with

   - a conveyor (3) for conveying the containers (2),

   - several stationary direct printing stations (5w, 5c, 5_M, 5γ, 5s, 5_K) attached thereto, with direct printing heads (52) for printing the containers (2) with the multicolour direct printing, and

   - with an ink supply system for supplying the direct printing stations (5w, 5c, 5_M, 5γ, 5s, 5_K) with several printing inks, wherein the ink supply system comprises a reservoir tank (51) for each ink colour,

   characterised in that
   the direct printing machine (1) comprises a refill station (6) with several mounting locations (630) for exchangeable refill tanks (631), wherein the mounting locations (630) are respectively designed to automatically pump printing ink from one of the refill tanks (631) into one of the reservoir tanks (51).
2. A direct printing machine according to claim 1, wherein the mounting locations (630) are arranged adjacent to a shelf-like receiving front (610), preferably above one another, next to one another or as a matrix.
3. A direct printing machine according to claim 2, wherein the refill station (6) is designed as a cabinet unit that is separate from the stationary direct printing stations (5w, 5c, 5M, 5y, 5s, 5_K) and the reservoir tanks (51), and is connected to them via connecting lines for the printing inks.
4. A direct printing machine according to one of the preceding claims, wherein the refill station (6) comprises at least one additional mounting location (650, 660) for a supply tank with a cleaning fluid and/or for a waste tank for the printing ink.
5. A direct printing machine according to one of the preceding claims, wherein the exchangeable refill tanks (631) each comprise a bag (631b) for holding the printing ink and a support structure (631c) that surrounds the bag (631b) at least partially, wherein the bag (631b) has an connection (631a) for extracting the printing ink, preferably wherein the bag (631b) consists at least partly of plastic and/or the support structure (631c) is designed as a support box.
6. A direct printing machine according to one of the preceding claims, wherein the mounting locations (630) each comprise a receptacle (632) for one of the exchangeable refill tanks (631), a connection coupling (633) for detachable connection to the accommodated exchangeable refill tank (631), and/or an ink pump (638) for pumping the printing ink out of the accommodated exchangeable refill tank (631) towards one of the reservoir tanks (51).
7. A direct printing machine according to claim 6, wherein the mounting locations (630) each comprise a valve block (639) upstream of the ink pump (638), in order optionally to pump printing ink out of the accommodated exchangeable refill tank (631) or ambient air towards the reservoir tank (51).
8. A direct printing machine according to one of the claims 6 or 7, wherein the mounting locations (630) each comprise at least one display element (635) for displaying an operating status.
9. A direct printing machine according to one of the claims 6 - 8, wherein the mounting locations (630) each comprise a data transmitter (637), preferably an RFID read/write head, and the exchangeable refill tanks (631) each have a data mark (631d), preferably an RFID mark, in order to exchange and/or store preferably encrypted data about the printing ink present in the respective exchangeable refill tank (631).
10. A direct printing machine according to one of the claims 5 - 8, wherein the mounting locations (630) are each designed as an exchangeable module and are connected to the refill station (6) via at least one fastening element (B).
11. A direct printing machine according to one of the claims 5 - 9, wherein the mounting locations (630) each comprise a carrier (642) for the ink pump (638) and/or the valve block (639) and a housing (643) at least partly surrounding the carrier (642) with the receptacle (632) for the exchangeable refill tank (631), wherein the receptacle (632) is preferably arranged as a storage surface on an outer face of the housing (643).
12. A direct printing machine (1) according to one of the claims 1 - 11, wherein the direct printing machine comprises an exchangeable refill tank (631), wherein the exchangeable refill tank (631) comprises a bag (631b) for accommodating the printing ink and a support structure (631c) which at least partly surrounds the bag (631b), wherein the bag (631b) has a connection (631a) for extracting the printing ink, preferably wherein the bag (631b) consists at least partly of plastic and/or the support structure (631c) is designed as a support box.
13. Direct printing method for printing containers (2) with multicoloured direct printing, wherein the containers (2) are conveyed with a conveyor (3), wherein the containers (2) are printed with multicoloured direct print by stationary direct printing stations (5w, 5c, 5_M, 5_Y, 5s, 5_K) attached to the conveyor (3), by means of direct printing heads (52), and wherein the direct printing stations (5w, 5c, 5_M, 5_Y, 5s, 5_K) are supplied by an ink supply system with several printing inks, each out of one reservoir tank (51),
    characterised in that
    exchangeable refill tanks (631) with the printing inks are accommodated in several mounting locations (630) of a refill station (6) and the printing inks are respectively automatically pumped from one of the exchangeable refill tanks (631) into one of the reservoir tanks (51).
14. Direct printing method according to claim 13, wherein the exchangeable refill tanks (631) for refilling the printing ink are in each case exchanged as a whole by an operator.
15. Direct printing method according to claim 13 or 14, wherein the entire content of printing ink in an exchangeable refill tank (631) is pumped into one of the reservoir tanks (51) as required.
16. Direct printing method according to one of the claims 13 - 15, wherein one of the exchangeable refill tanks (631) is shaken by an operator to avoid sedimentation and a time of shaking is recorded in a data mark (631d) of the refill tank (631), preferably in an RFID mark.

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