EP3450183B1 - Direct printing machine and method for printing on containers by means of direct printing - Google Patents

Description

The invention relates to a direct printing machine and a direct printing method for printing containers with direct printing 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 comprise a transporter for transporting the containers and a number of direct printing modules attached thereto in order to print the containers with direct printing. For example, the containers are picked up by the transporter in container receptacles and transported to the direct printing modules that are stationarily attached to them. With the direct printing modules, the containers are each rotated by means of the container receptacles and are thereby printed with 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 multicolored direct printing, the containers are transported past the direct printing modules and are printed there sequentially with printing inks of different colors, for example white, cyan, magenta, yellow and black.

the DE 10 2013 214 980 A1 discloses a printing machine having a traversing system for adjusting the position of a printhead module, the traversing system comprising a radial module for adjusting the position of the printhead module in a radial direction and a height module for adjusting the height of the printhead module in a vertical direction. Furthermore, a tilting module is proposed in order to pivot the print head module and thus guide it along a lateral slope of a container.

A disadvantage of the known direct printing machines is that when the direct printing module is pivoted, its supply lines are moved and can therefore protrude. Consequently, the pivoting movement requires a certain space for the supply lines, which is why a minimum distance to an adjacent direct printing module must then be increased. In addition, the supply lines are stressed by the cantilever and are therefore subject to wear.

Furthermore, it is disadvantageous that when changing the pivotable direct printing modules, a high level of installation effort is required and thus, in rare cases, there is a risk of contamination.

the U.S. 4,901,095 A discloses an ink jet printing device with an adjustable print head.

the CN 202 319 300 U discloses a machine for under glass painting on ceramics.

It is therefore the object of the present invention to provide a direct printing machine which allows a more compact arrangement when direct printing modules are pivoted and in which the stress on the supply lines is reduced. Furthermore, it is the object of the present invention to reduce the risk of contamination when changing.

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

Because the direct printing modules can be replaced as a unit, they can be removed from the direct printing machine and reinserted particularly quickly when changing. This reduces the risk of contamination of the direct printing modules.

Due to the fact that the direct printing modules are each formed in two parts with an intermediate rotary joint, the print head part with the at least one direct print head can be pivoted about the pivot axis relative to the connection part. Consequently, only the print head part with the at least one direct print head is pivoted and not the connection part that is used to connect the module to the ink supply system. Accordingly, the print head part can be made particularly compact, as a result of which the supply lines protrude particularly little and the space required for the pivoting movement of the module parts is reduced. This enables a more compact arrangement of the direct printing modules and the supply lines are less stressed.

The direct printing machine can be arranged in a beverage processing plant. The direct printing machine can be a filling system for filling a product into the container and/or be downstream of a capper for capping the containers with caps. 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 it, it can be 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. It is also conceivable that the containers are provided for a non-flowable filling material, for example capsules, tablets, pastes and/or cleaning stone. 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 modules 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 direct printing modules 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 of the direct printing modules.

The direct printing modules can be arranged in a stationary manner. “Stationary” direct printing modules can mean here that the direct printing modules are arranged in a stationary or fixed manner relative to a machine base or a standing surface for the direct printing machine. Alternatively, it is also conceivable that the direct printing modules are arranged to run along on the conveyor, and in particular are each assigned to one of the container receptacles. It is conceivable that the direct printing modules are assigned to direct printing stations individually or in groups, with the direct printing stations each being provided for printing ink of a specific color. For example, a first direct printing station with a group of direct printing modules can only be provided for printing the color white and a second direct printing station with a further group of direct printing modules can only be provided for printing the color cyan, or then further direct printing stations with further groups of direct printing modules for printing the colors magenta , yellow, black and/or special colors.

The direct print modules can each include one or more direct print heads. The direct print heads can work with a digital or inkjet printing process in which the Printing ink is delivered to the containers by means of a plurality of printing nozzles. "Inkjet printing process" can mean here that a sudden increase in pressure is generated in chambers of a printing nozzle via piezoelectric or thermal elements in such a way that a small amount of printing ink is pressed through the printing nozzle and delivered to the container as a printing 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.

The fact that the direct printing modules are "each designed to be interchangeable as a unit" can mean here that the print head part, the connecting part and the rotary joint in between form a mechanically coherent unit that can be decoupled from or coupled to the direct printing machine as a whole. Preferably, the print head portion and the receiving portion may comprise two support structures pivotally connected to each other via the pivot joint. Preferably, the at least one direct print head can be arranged on one of the support structures and the connection elements described further below and optionally the control module can be arranged on the other support structure.

The ink supply system can include at least one storage tank, at least one ink pump and/or supply lines. The supply lines can be provided to connect the at least one storage tank to the connection part of at least one of the direct printing modules via the at least one ink pump. In particular, the supply lines can be designed at least partially as flexible ink hoses.

In addition to pivoting, the adjusting units can also be designed to adjust the height and/or the printing distance of the respective direct printing module. The adjusting units can preferably each comprise a first linear drive for adjusting the height and/or a second linear drive for adjusting the printing distance of one of the direct printing modules. “Printing distance adjustment” can mean here that a distance between the direct printing module and a container to be printed is changed. This can be a vertical distance between a nozzle plate and a print area on the container.

The adjustment units can include first support elements for connection to the stationary machine base and/or the standing area for the direct printing machine. It is also conceivable that the adjustment units each include second support elements with the drives for pivoting the direct printing modules. For example, the second support element can be designed as an arm that can be moved vertically and/or horizontally with the adjustment unit, on which one of the Direct printing modules and / or the module holder described below is arranged. Preferably, the second support element can be moved via at least one linear motor.

The direct printing machine can include a control unit for controlling the direct printing modules, the direct print heads, the adjustment unit 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.

The adjustment units can each include a module mount to accommodate the direct print head modules and to lock them with a quick-release fastener. As a result, the direct printing modules can be changed particularly quickly. The quick-release fastener can include two coupling elements, one of which is arranged on the module receptacle and the other on the direct printing module. In addition, the quick-release fastener can include a locking means in order to selectively lock or release the two coupling elements with one another. The module receptacles can preferably each comprise one of the drives in order to pivot the direct print head module received therein.

The module receptacles can each be formed in two parts with an intermediate drive swivel joint in order to pivot a first receptacle for the printhead part relative to a second receptacle for the connector part about the drive swivel joint. The two-part design of the module mounts reduces the space of the module mount required for the pivoting movement, as a result of which the module mounts can also be arranged in a particularly compact manner. In other words, the module holders move together with the direct printing modules to pivot. The rotary drive joint of the module holder and the rotary joint of the direct printing module held therewith can preferably be coaxial with the pivot axis. As a result, both the print head part and the first receptacle pivot together about the pivot axis.

The drives can each be designed for direct pivoting of the first receptacle relative to the second receptacle about the drive swivel joint in order to indirectly pivot the print head part of the received direct printing module relative to the connection part about the swivel joint. As a result, the recorded direct printing module is passively swiveled by the module holder so that it does not need its own drive. Consequently, the direct printing module, which can be exchanged as a unit, can be constructed in a particularly compact manner.

The direct printing modules can each include a feed and/or a return hose for the ink supply, which are routed from the connection part to the print head part in the area of the swivel joint at a distance of 0-10 cm, in particular 0-5 cm from the pivot axis, so that a change in length of the flow and/or return hose is minimized when pivoting. As a result, the flow and/or return hose are subjected to less stress as a result of the pivoting and wear is reduced. In other words, the flow and/or the return hose run as close as possible to the pivot axis. "Distance to the pivot axis" can mean the minimum vertical distance of a hose center line to the pivot axis.

The direct printing modules can each include a pressure sensor for measuring an ink pressure, which is preferably arranged in the print head part. As a result, pressure losses through the supply lines of the direct printing modules are not taken into account when measuring the ink pressure. Consequently, the meniscus pressure in the direct print heads of the direct print modules can be adjusted more precisely.

The direct printing modules can each include a plurality of connection elements for control and for ink supply, which are arranged on the connection part. As a result, the supply lines for the controller and for the ink supply are not moved when swiveling and are therefore not subject to any bending stress.

The connection elements can include at least one quick coupling for detachable connection to at least one supply line of the ink supply system. As a result, the supply lines can be pulled off the direct printing modules particularly quickly so that they can be changed more quickly. The quick couplings can be designed to be non-drip in order to prevent the printing ink from leaking out. Furthermore, the connection elements can comprise at least one further quick coupling for detachable connection to a suction device. As a result, for example, a pressure mist extraction system in the direct pressure modules can be supplied with a negative pressure via the connection elements. It is also conceivable that the connection elements include at least one electronic plug for power supply, for data exchange and/or for control signals of the direct printing module.

The at least one quick coupling can be provided for connecting the feed and/or return hose to at least one supply line of the ink supply system.

It is also conceivable that the connection elements are integrated into a connection block. As a result, the individual connection elements do not have to be separated from the supply lines, which means that changing the direct printing modules is even faster. For example, the connection block can be designed as a multi-coupling.

The direct printing modules can each include a control module, which is preferably arranged in the connection part. This further reduces the space required in the print head part, so that the direct print modules can be arranged in an even more compact manner. The control module can be connected to the at least one direct print head of the direct print module in order to control the print nozzles. The control unit described above can comprise and/or be connected to the control modules. For example, the direct printing machine can include a central control unit that is connected to the direct printing modules via connecting lines.

The direct printing modules can each include a print mist extraction system, the at least one intake opening of which is arranged in the print head part adjacent to a nozzle plate of the direct print head. This allows ink droplets caused by air movements to be sucked out so that they do not uncontrollably soil other container parts or surfaces of the direct printing machine.

In addition, the invention with claim 13 provides a direct printing method for printing containers with a direct print. Advantageous embodiments of the invention are specified in the dependent claims.

Because the direct printing modules are exchanged as a unit for maintenance, they can be removed from the direct printing machine and reinserted particularly quickly in the event of a change. This reduces the risk of contamination of the direct printing modules.

Due to the fact that, in order to adapt the direct printing modules to the longitudinal contour of the container, a print head part with at least one direct print head is pivoted about the pivot axis relative to a connection part for connection to the ink supply system by means of an intermediate rotary joint, in the direct printing method according to the invention only the print head part with the at least one direct print head is pivoted and not the connector. Accordingly, the print head part can be designed to be particularly compact, as a result of which on the one hand the supply lines protrude particularly little and on the other hand the space required for the pivoting movement of the module parts is reduced. This creates a more compact Arrangement of the direct printing modules possible and the supply lines are less stressed.

The direct printing method can be carried out with the direct printing machine described above, preferably according to one of claims 1-12. Furthermore, the direct printing method can include the features described above in relation to the direct printing machine individually or in any combination.

It is conceivable that the direct printing modules are each received in a module receptacle of the associated adjustment unit and are locked in place with a quick-release fastener. As a result, the direct printing modules can be changed particularly quickly.

In the case of the module receptacles, a first receptacle for the print head part can preferably be pivoted directly relative to a second receptacle for the connection part about a drive swivel joint in order to indirectly pivot the print head part of the received direct printing module relative to the connection part about the swivel joint. In other words, the printhead portion of the received direct print module is pivoted passively over the first mount of the module mount. As a result, the drives cannot be arranged in the direct printing modules but in the module receptacles, with the drive movements being transmitted purely mechanically from the module receptacles to the direct printing modules. As a result, the direct printing modules can be made even more compact.

Figur 1

eine Übersichtsdarstellung einer erfindungsgemäßen Ausführungsform einer Direktdruckmaschine zur Bedruckung von Behältern mit einem Direktdruck in einer Draufsicht;

Figur 2

eine seitliche Detailansicht der Direktdruckmaschine aus der Figur 1 mit dem Transporteur und den daran angegliederten Direktdruckmodulen einer Direktdruckstation;

Figuren 3A - 3B

eine perspektivische Detailansicht eines Direktdruckmoduls und einer Modulaufnahme;

Figuren 4A - 4B

eine seitliche Ansicht des in den Figuren 3A - 3B dargestellten Direktdruckmoduls bei zwei verschiedenen Schwenkstellungen des Druckkopfteils;

Figur 5

die Führung des Vorlauf- und Rücklaufschlauchs innerhalb des Direktdruckmoduls aus den Figuren 3A - 4B in einer seitlichen Ansicht; und

Figur 6

eine frontale Ansicht auf die Druckmodulfrontplatte des Direktdruckmoduls aus den Figuren 3A - 5.

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 overview of an inventive embodiment of a direct printing machine for printing containers with a direct print in a plan view;

figure 2

a detailed side view of the direct printing machine from FIG figure 1 with the conveyor and the attached direct printing modules of a direct printing station;

Figures 3A - 3B

a perspective detailed view of a direct printing module and a module receptacle;

Figures 4A - 4B

a side view of the in den Figures 3A - 3B shown direct printing module in two different pivot positions of the print head part;

figure 5

the routing of the flow and return hoses within the direct printing module from the Figures 3A - 4B in a side view; and

figure 6

a frontal view of the print module front panel of the direct print module from the Figures 3A - 5 .

In the figure 1 1 is an overview of an embodiment of a direct printing machine 1 according to the invention for printing containers 2 with direct printing 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 starwheel 10 and are received in the container receptacles 4 there. Picked up in this way, they are transported by the transporter 3 past the attached direct printing stations _5w , _5c , 5M, _5Y , 5K and each printed with different colors by means of the direct printing modules 50, here for example according to the indices with white, cyan, magenta, yellow and Black. This creates a multicolored direct print on the containers 2 . The direct print applied to the containers is then cured with the curing station 8 and thereby permanently stabilized, for example by means of UV light. The finished printed containers 2 are then transferred to the discharge star wheel 11 and forwarded to subsequent treatment stations, for example to a packaging machine. A control unit 9 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 4a and a centering bell 4b (see Fig 2 ), so that the containers 2 can be rotated about their longitudinal axes during the printing process relative to the respective stationary direct printing station _5w , _5c , 5M, _5Y , 5K. This allows a flat direct print to be generated.

In addition, the adjustment units 6 for adjusting the direct printing modules 50 relative to the containers 2 to be printed can be seen, which are explained in more detail below:
In the figure 2 is a detailed side view of the direct printing machine 1 from FIG figure 1 with the transporter 3 and the attached direct printing modules 50, 50', 50" of one of the direct printing stations 5 _W , 5 _C , 5 _M , 5 _Y , 5 _K. You can see the transporter 3 with the lower carousel plate 3a, the upper carousel plate The support column 3c is driven about the axis A by a carousel drive, not shown in detail here, so that the conveyor 3 rotates in the transport direction T.

It can also be seen that the turntable 4a is attached to the lower carousel plate 3a and the centering bells 4b to the upper carousel plate 3b as container receptacles 4 in order to accommodate the containers 2 during transport or printing. The turntables 4 are driven here, for example, by direct drives (not shown), but cams or the like are also conceivable. As a result, the containers 2 can be rotated about their longitudinal axes L relative to the direct printing modules 50, 50′, 50″ during printing in order to produce a two-dimensional direct printing 2a, 2b.

The direct printing modules 50, 50', 50" have the same structure and differ only in their position relative to the container 2. However, it is also conceivable that two or more of the direct printing modules 50, 50', 50" occupy the same height position relative to the container 2 , in order to apply printing ink to the container 2 in the same printing area (with, for example, half the height of the direct printing 2a). This can either increase machine performance or improve ink application. The container shoulder is printed with the direct printing module 50 and the container body is printed with the direct printing modules 50', 50" in the two separate areas 2a, 2b. The traversing unit 6 can be controlled with the control unit 7 in such a way that the direct printing modules 50, 50', 50" each can be moved in the directions R ₁ , R ₂ or pivoted about the pivot axis S in the direction R ₃ . The positioning of the direct printing modules 50, 50', 50" can be flexibly selected. It is conceivable, for example, that all direct printing modules 50, 50', 50" are positioned in such a way that they print only the container body or two direct printing modules 50, 50' the container shoulder.

In the following, only the direct printing module 50 or the adjustment unit 6 will be described only in relation to the direct printing module 50 . However, the statements also apply equally to the direct printing modules 50', 50".

The direct printing module 50 can be adjusted axially with the adjusting unit 6 in the direction R ₁ and radially in the direction R ₂ relative to the longitudinal axis L of the container 2 to be printed. As a result, on the one hand the height and on the other hand the printing distance of the direct printing module 50 relative to the container 2 can be adjusted. It can also be seen that the adjusting unit 6 is designed to pivot the direct printing module 50 about the pivot axis S for adaptation to the longitudinal container contour C. It can be seen that the container 2 has a shoulder area in a transition from the container body to the neck, which runs obliquely to the longitudinal axis L of the container. Consequently, the direct print head, not shown here, of the direct print module 50 must be tilted in order to achieve a particularly high print quality.

For this purpose, the direct printing modules 50, 50', 50" are each designed in two parts with an intermediate rotary joint 43 in order to pivot the print head part 51 with the direct print head, which is not shown in detail here, in relation to the connection part 52 about the pivot axis S in the direction R _3. This allows in In this example, the uppermost direct print module 50 can be pivoted so that the print head part 51 with the direct print head in the shoulder area is aligned as parallel as possible to the contour C. The connection part 52 is used for connection to the ink supply system.

Due to the fact that the direct printing modules 50, 50', 50" are each designed in two parts with the print head part 51, the connecting part 52 and with the rotary joint 53 in between, the print head part 51 can be made particularly compact, so that as little as possible is required for pivoting about the pivot axis S space is occupied. Consequently, the direct printing modules 50, 50', 50" can be arranged very compactly.

In addition, the direct printing modules 50, 50′, 50″ are each designed to be exchangeable as a unit, which is explained below on the basis of Figures 3A - 3B is explained in more detail:
In the Figure 3A - 3B a perspective detailed view of the direct printing module 50 and a module receptacle 60 is shown, with the direct printing module 50 being attached to the adjustment unit 6 via the module receptacle 60 .

It goes without saying that the others in the figure 2 shown direct printing modules 50', 50" are constructed in the same way and are each attached to the adjustment unit 6 via such a module receptacle 60.

The module recording 60 is in the Figure 3A shown left end connected to the adjustment unit 6. The replaceable direct print head module 50 can be accommodated in the module receptacle 60 and locked with the quick-release fastener 65 . This makes it possible to change the direct printing module 50 particularly quickly during maintenance, and the risk of contamination is reduced.

It can also be seen that the interchangeable direct printing module is designed in two parts with the print head part 51 and the connector part 52, the print head part 51 being pivotable about the pivot axis S relative to the connector part 52 with the pivot joint 53 in between. This makes it possible to pivot the print head part 51 about the pivot axis S without changing the position of the connection part 52 in relation to the adjustment unit 6 . In addition, the module mount 60 is also formed in two parts, with the first mount 61 for the print head part 51 and the second mount 62 for the connection part 52 of the direct printing module 50, with the first mount 61 being able to pivot relative to the second mount 62 by the rotary drive joint 63 located in between. In addition, the rotary drive joint 63 of the module receptacle 60 and the rotary joint 53 of the direct printing module 50 accommodated therein are configured coaxially to the pivot axis S, so that they both pivot about the pivot axis S.

The drive 64 can also be seen, with which the first receptacle 61 is pivoted relative to the second receptacle 62 about the rotary drive joint 63 . As a result, the print head part 51 of the received direct printing module 50 is moved relative to the connection part 52 indirectly. In other words, the direct printing module 50 does not have its own drive, but is passively pivoted by the pivoting movement of the module receptacle 60 .

In the Figure 3B A perspective view of the direct print module 50 can be seen. It can be seen that the print head part 51 and connection part 52 each comprise a carrier which is pivotably connected to one another via the pivot joint 53 . The direct print head 58 , the print module front panel 56 and a latching element 55 for connection to the quick-release fastener 65 are arranged on the carrier of the print head part 51 . In contrast, the connection elements 59.1-59.7 and the control module 70 are arranged on the support of the connection part 52. Furthermore, the direct print module 50 includes the pressure sensors 72.1, 72.2 for measuring the ink pressure, which are arranged here, for example, in the connection part 52, but can alternatively be arranged in the print head part 51. As a result, the ink pressure is measured as close as possible to the direct print head 58, so that the measured values are affected as little as possible by pressure losses.

The connection elements 59.1 and 59.2 serve to supply ink to the direct print head 58 and include quick-release couplings in order to connect them to supply lines 67.1, 67.2 of the ink supply system in a detachable manner Figure 3A are shown. Furthermore, the connection elements 59.3, 59.4 can be seen, which are also designed as quick couplings and are used for the detachable connection of the direct printing module 50 to a suction device. This creates a vacuum for those in the figure 6 Pressure mist extraction 71 shown provided. The connection sockets 59.5, 59.6 for the pressure sensors 72.1, 72.2 for measuring the ink pressure and the connection sockets 59.7 for the control module 70 can also be seen. With the connection elements 59.1-59.7, the direct printing module 50 can be uncoupled from the supply lines, exchanged and reconnected particularly quickly. Due to the fact that the connection elements 59.1-59.7 for control and for ink supply are arranged on the connection part 52, the supply lines are not moved when the print head part 51 is pivoted and therefore protrude less or not at all. Consequently, less space has to be provided for supply lines protruding from the direct printing module 50 during pivoting.

Due to the fact that the control module 70 is also arranged on the connection part 52, corresponding installation space is saved in the print head part 51, so that it can be constructed in a particularly compact manner. Consequently, the space for pivoting about the pivot axis S is further reduced.

In the Figures 4A - 4B is a side view of the in the Figures 3A - 3B shown direct printing module 50 in two different pivoted positions of the print head part 51 to see.

In the Figure 3A and 4B the print head part 51 is pivoted downwards, for example to print the container shoulder. However, it is also conceivable that the print head part 51 is swiveled upwards, for example in order to print on a container base.

In the Figure 4A the direct print module 50 can be seen in a first pivoted position in which the print drops I are discharged essentially horizontally from the nozzle plate 58.1 of the direct print head 58. For this purpose, the print head part 51 is rotated about the swivel joint 53 relative to the connection part 52 in such a way that both parts are aligned in the same direction. In this pivoted position are, for example, in the figure 2 illustrated direct printing modules 50', 50", in order to print the first part of the direct printing 2a on the container body. Here, the container contour C runs essentially parallel to the longitudinal axis L of the container.

In the Figure 4B the direct print module 50 can be seen in a second pivoted position, in which the print drops I are discharged from the nozzle plate 58.1 of the direct print head 58 at an angle α relative to the horizontal, obliquely downwards. For this purpose, the print head part 51 is pivoted about the swivel joint 53 in the direction R ₃ about the pivot axis S relative to the connection part 52 . For this purpose, the in the Figure 3A illustrated drive 64 on the first receptacle 61, so that it is pivoted together with the print head part 51 about the swivel axis S. In this pivoted position, for example, is in the figure 2 shown direct printing module 50 in order to print the shoulder area with the second part 2b of the direct printing.

In the figure 5 is the leadership of the flow and return hose 57.1, 57.2 within the direct printing module 50 from the Figures 3A - 4B shown in a side view. It can be seen that the feed hose 57.1 and the return hose 57.2 for the ink supply of the direct print head 58 are laid at a distance of 0 - 5 cm from the pivot axis S, so that they only bend during the pivoting movement with little or no change in length. As a result, the feed and return hoses 57.1, 57.2 protrude as little as possible, so that the installation space required for this is reduced. The two supply hoses 57.3, 57.4 of the pressure mist extraction 71 can also be seen, which are also laid at a distance of 0-5 cm from the pivot axis S. As a result, these hoses also experience the least possible change in length and protrude less or not at all.

In the figure 6 12 is a front view of the print module front panel 56 of the direct print module 50 of FIGS Figures 3A - 5 shown. In this perspective, on the one hand, the nozzle plate 58.1 with the printing nozzles D of the direct print head 58 and the openings L of the print mist extraction 71 can be seen.

It can be seen that the pressure nozzles D are arranged in two nozzle rows 58.2, 58.3 in the nozzle plate 58.1. However, only one row of nozzles or three, four or even more rows of nozzles are also conceivable. Furthermore, the openings L of the pressure mist extraction 71 are also arranged in two rows 71.1, 71.2 adjacent to the nozzle plate 58.1. As a result, drops of ink that are swirled around by the wind and that would otherwise be deposited on other areas of the container or machine parts can be sucked off.

The in the Figures 1 - 6 The direct printing machine 1 shown is used as follows:
The containers 2 are transported with the conveyor 3 and printed with the direct print 2a, 2b with the direct print modules 50, 50', 50" attached thereto, with the direct print modules 50, 50', 50" being adjusted with adjustment units 6 in relation to the containers 2 to be printed whereby drives 64 of the adjusting units 6 each pivot one of the direct printing modules 50, 50', 50" about a pivot axis S for adaptation to a longitudinal container contour C. As a result, the position of the direct printing modules 50, 50', 50" is thus adapted to the container contour C that the highest possible quality of direct printing 2a, 2b is possible. To adapt the direct printing modules 50, 50', 50" to the longitudinal container contour C, the print head part 51 with the direct print head 58 is pivoted about the pivot axis S opposite the connection part 52 for connection to the ink supply system by means of the intermediate swivel joint 53. This is necessary for the pivoting movement Installation space is particularly small and the direct printing modules 50, 50', 50" can be arranged in a particularly compact manner in relation to one another.

During maintenance and a malfunction, the direct print modules 50, 50', 50" are each stored as a unit (as in Figs Figure 3B shown) exchanged. As a result, the change can be carried out particularly quickly, so that contamination of the direct printing modules 50, 50', 50" is avoided. When changing, the direct printing modules 50, 50', 50" are each received in a module receptacle 60 of the associated adjustment unit 6 and with a quick-release fastener 65 can be locked.

In the case of the module mounts 60, a first mount 61 for the print head part 51 is pivoted directly about a rotary drive joint 53 relative to a second mount 62 for the connection part 52 in order to indirectly pivot the print head part 51 of the received direct printing module 50 relative to the connection part 52 about the rotary joint 53 . As a result, the direct printing modules 50, 50', 50'' do not require their own drives and can therefore be constructed in a particularly compact manner.

Claims (15)

1. Direct printing machine (1) for printing containers (2) with a direct print (2a, 2b), comprising

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

   - a plurality of direct print modules (50, 50', 50") attached thereto for printing the containers (2) with the direct print (2a, 2b), and

   - adjusting units (6) for adjusting the direct print modules (50, 50', 50") in relation to the containers (2) to be printed, wherein the adjusting units (6) having drives (64) are designed to swivel one each of the direct print modules (50) about a swivel axis (S) for adjusting to a longitudinal container contour (C), characterised in that

   the direct print modules (50, 50', 50") are each interchangeable as a unit, and

   in that the direct print modules (50, 50', 50") are each designed in two parts with a rotary joint (53) between them such that a print head part (51) having at least one direct print head (58) can be swivelled about the swivel axis (S) in relation to a connecting part (52) for connecting to an ink supply system.
2. Direct printing machine (1) according to claim 1, wherein the adjusting units (6) each comprise a module holder (60) to hold the direct print head modules (50, 50', 50") and to lock them into position with a snap closure (65).
3. Direct printing machine (1) according to claim 2, wherein the module holders (60) are each designed in two parts with a rotary drive joint (63) between them in order to swivel a first holder (61) for the print head part (51) in relation to a second holder (62) for the connecting part (52) about the rotary drive joint (63), preferably wherein the rotary drive joint (63) of the module holder (60) and the rotary joint (53) of the direct print module (50) held therein are coaxial to the swivel axis (S).
4. Direct printing machine (1) according to claim 3, wherein the drives (64) are each designed to swivel the first holder (61) in relation to the second holder (62) about the rotary drive joint (63) in order to indirectly swivel the print head part (51) of the held direct print module (50) about the rotary joint (53) in relation to the connecting part (52).
5. Direct printing machine (1) according to any of the preceding claims, wherein the direct print modules (50, 50', 50") each comprise a feed and/or a return hose (57.1, 57.2) for the ink supply, with said hoses extending from the connecting part (52) to the print head part (51) in the region of the rotary joint (53) at a distance of 0 - 10 cm, in particular of 0 - 5 cm, from the swivel axis (S), so that a change in length of the feed and/or return hose (57.1, 57.2) is minimised when swivelling.
6. Direct printing machine (1) according to any of the preceding claims, wherein the direct print modules (50, 50', 50") each comprise a pressure sensor for measuring an ink pressure, with said sensor preferably being arranged in the print head part (51).
7. Direct printing machine (1) according to any of the preceding claims, wherein the direct print modules (50, 50', 50") each comprise a plurality of connecting elements (59.1 - 59.7) for control and ink supply purposes, which are arranged on the connecting part (52).
8. Direct printing machine (1) according to claim 7, wherein the connecting elements (59.1 - 59.2) comprise at least a quick coupling for a detachable connection to at least one supply line (67.1, 67.2) of the ink supply system.
9. Direct printing machine (1) according to claims 5 and 8, wherein the at least one quick coupling is provided for connecting the feed and/or return hose to the at least one supply line (67.1, 67.2).
10. Direct printing machine (1) according to any of claims 7-9, wherein the connecting elements (59.1 - 59.7) are integrated into a connection block.
11. Direct printing machine (1) according to any of the preceding claims, wherein the direct print modules (50, 50', 50") each comprise a control module (70) which is preferably arranged in the connecting part (52).
12. Direct printing machine (1) according to any of the preceding claims, wherein the direct print modules (50, 50', 50") each comprise a print mist extraction system (71), with the at least one intake opening (L) thereof being arranged in the print head part (51) adjacent to a nozzle plate (58.1) of the direct print head (58).
13. Direct print method for printing containers (2) with a direct print (2a, 2b), wherein the containers (2) are conveyed by a conveyor (3) and printed with the direct print (2a, 2b) by means of a plurality of direct print modules (50, 50', 50") attached thereto, wherein the direct print modules (50, 50', 50") are adjusted in relation to the containers (2) to be printed by adjusting units (6), and wherein drives (64) of the adjusting units (6) each swivel one of the direct print modules (50, 50', 50") about a swivel axis (S) for adjusting to a longitudinal container contour (C),
    characterised in that

    the direct print modules (50, 50', 50") are each interchanged as a unit for maintenance purposes, and

    in that, for adjusting the direct print modules (50, 50', 50") to the longitudinal container contour (C), a print head part (51) having at least one direct print head (58) is swivelled in each case in relation to a connecting part (52) for connecting to an ink supply system by means of a rotary joint (53) between them about the swivel axis (S).
14. Direct print method according to claim 13, wherein the direct print modules (50, 50', 50") are each held in a module holder (60) of the associated adjusting unit (6) and locked into position with a snap closure (65).
15. Direct print method according to claim 14, wherein, in the case of the module holders (60), a first holder (61) for the print head part (51) is directly swivelled in relation to the second holder (62) for the connecting part (52) about a rotary drive joint (53) in order to indirectly swivel the print head part (51) of the held direct print module (50) in relation to the connecting part (52) about the rotary joint (53).

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