EP3044001A1

EP3044001A1 - Printing system and printing device for bottles or containers having a multi-part supply tank, and method

Info

Publication number: EP3044001A1
Application number: EP14753083.6A
Authority: EP
Inventors: Markus Reiniger
Original assignee: KHS GmbH
Current assignee: KHS GmbH
Priority date: 2013-09-13
Filing date: 2014-08-20
Publication date: 2016-07-20
Anticipated expiration: 2034-08-20
Also published as: US9630414B2; DE102013110108A1; JP2016536175A; US20160221346A1; JP6421189B2; EP3044001B1; WO2015036215A1

Abstract

The invention relates to a printing system for printing bottles or similar containers (2), having a moving printing system part (10), on which there is provided at least one electric print head (3, 3a) operating on the inkjet principle and movable along a transport section for the containers (2), preferably movable in circulation, for printing the respective container (2) arranged at a printing station (4.1), and a static printing system part (8), not moved together with the print head (3), which has at least one tank (100) for holding printing color or ink to be supplied to the print head (3).

Description

Printing system and printing device for bottles or containers with multi-part supply tank and method.

The invention relates to a printing system according to the preamble of claim 1 and to a printing apparatus according to the preamble of claim 14, and a method for mixing and stirring of printing ink or ink according to the preamble of the patent award 15th

Printing devices for printing on containers using digital, based on the inkjet or inkjet principle electric or electronic printheads are known in principle. In particular, printing systems or printing machines are known in which a plurality of printing stations for receiving a respective container to be printed are formed on a rotatably driven around at least one vertical axis container transport element, in particular on a rotatably driven about a vertical machine axis rotor on which the container using be printed by electronically controllable, working on the inkjet or inkjet principle digital printheads. The print heads are provided on a likewise about the at least one vertical axis circumferentially drivable print head transport element, which is for example the container conveyor or an independent transport element. In any case, the printheads are located on a moving, for example, rotating part of the respective printing device or - machine. Such printing devices typically have a first, stationary arranged, for example, on the floor upstanding printing device part and a second, moving relative to the first printing device part printing device part. The print heads or the container carriers are arranged on the second printing device part. The first printing device part has at least a part of a supply system for supplying the printing heads with printing ink or ink, in particular a tank for storing ink or ink. To remove the ink or ink from the first, stationary printing device Part to promote the second, moving Druckvorhchtungsteil, usually a conduit system is provided with a rotary coupling disposed therein, ie, the rotary coupling forms the coupling piece between the stationary part and moving part of the conduit system.

In particular, when a plurality of such lines run from the first printing device part to the second printing device part, the necessary rotary joints represent a considerable investment. In addition, often the centered arrangement of the rotary joints in the region of the axis of rotation about which rotates the first printing device part, not possible.

The object of the invention is to show a printing system, which allows optimized in terms of effort and placement coupling between the stationary part and moving part of the pipe system. To solve this problem, a printing system according to the patent claim 1 is formed. A method of blending and stirring ink or ink is the subject of independent claim 15. In a first aspect, the invention relates to a printing system for printing on bottles or similar containers. The printing system has a moving, in particular rotationally moving printing system part, on which at least one operating according to the ink jet principle and along a transport path for the container movable, preferably circumferentially movable electric or electronic print head for printing the respective arranged on a printing station container is provided. Furthermore, the printing system comprises a static, not with the printhead mitbewegten printing system part, which has at least one tank, hereinafter also referred to as the main tank, for receiving from the print head to be supplied ink or ink. To effect coupling between the static printing system member and the moving printing system member for transferring the ink or ink from the statically arranged receiving space for the ink or ink to the at least one printhead the tank is designed in several parts, wherein a first tank part is arranged statically and a second tank part is formed mitbewegbar with the moving pressure system part. This can be achieved with reduced investment costs, a coupling between the static pressure system part and the moving pressure system part.

In a preferred embodiment, the first part of the tank forms, as a lower part of the tank, the receiving space for the ink or ink to be stored. Thus, the receiving space is arranged statically and there are no movement-related forces, in particular centrifugal forces on the ink or ink.

Preferably, the second tank part closes as the upper part of the tank, the first part of the tank. Thus, a closed tank is obtained, the receiving space is completed to the outside. Preferably, the second tank part is formed as the first tank part occlusive lid.

In a preferred embodiment, the first and second tank part is fluid-tightly connected to each other. Thus, despite the relative movement of the first and second tank part to each other a tank is achieved, which effectively prevents leakage of ink or ink or intrusion of foreign substances into the receiving space of the tank. In this case, the seal between the first and second tank part may be formed as an annular seal, for example as an O-ring or a sliding seal, for example comprising graphite or ceramic.

Alternatively it can be provided as a seal, a gap seal, in particular a liquid-filled gap seal. This type of seal offers the advantage of a reduced coefficient of friction compared to the aforementioned types of seals.

Preferably, the interior of the tank is designed to be acted upon with an inert gas to produce a barrier gas flow through a gap formed between the first and second tank part. This barrier gas flow prevents ambient air from entering the receiving space, which has a positive effect on the storability of the printing ink or ink in the tank. In a preferred embodiment, the second tank part is designed to be height adjustable relative to the first tank part. As a result, the first tank part can be placed in an optimum height for the tightness of the tank or the friction between the first and second tank part. The height adjustment can be achieved, for example, by length-adjustable coupling elements, by means of which the second tank part is mechanically connected to the moving pressure system part. In a preferred embodiment, the first and / or second tank part is annular, in particular annular, with a central opening. With a centric arrangement of the tank in such a way that the center vertical axis of the tank coincides with the axis of rotation of the rotationally moved pressure system part, the opening thus comes to lie in the region of the axis of rotation. In this way, further lines can be routed through the tank or, within the opening, a drive for driving the moving pressure system section can be placed.

Preferably, the second part of the tank has at least one pipe of tubular construction, one free end of which extends into the receiving space formed by the first tank part, or the second tank part has a plurality of tubular ducts preferably offset at fixed angular intervals, the free ends of which in the extend into the receiving space formed by the first part of the tank. During the movement of the moving printing system part and thus the movement of the coupled with the moving printing system part second part of the tank part of the at least one line is moved by the ink or ink, so that the ink or ink is thereby stirred. This prevents the sedimentation or a separation and separate deposition of the ink constituents. Furthermore, preferably, the free end of the at least one line may have at least one laterally projecting stirring section. This stirring section can, for example, by a laterally from the outer wall of the tubular Line protruding flat portion, for example, a Flachmaterialab- section are formed. It is understood that several such Rührabschnitte can be provided on a line. As a result, the stirring or circulation effect is substantially improved.

Alternatively, the second tank part may have at least one stirring section extending into the receiving space of the first tank part. This stirring section can be formed separately from the lines and be arranged, for example, projecting downwards at the cover section of the second tank part.

Particularly preferably, the first tank part on several separate chambers for receiving ink or ink. Thus, a plurality of different printing inks or inks, for example, with different colors, but also next to the ink or ink a cleaning fluid for cleaning the printheads can be added to the tank.

Particularly preferably, the moving printing system part in addition to the at least one print head on at least one auxiliary tank for the ink or ink to which the at least one print head is connected.

In a preferred embodiment, the co-moving or rotating part of the printing system has a plurality of print heads, and the at least one sub-tank is common to all the print heads. In a preferred embodiment, means for controlling and / or regulating the pressure and / or the level of the filling level, i. the ink level provided in the at least one auxiliary tank.

In a further preferred embodiment, the at least one auxiliary tank has a tank interior which is in communication with the at least one print head and serves for receiving the printing ink or ink and for regulating of the ink level in the tank interior is formed with an overflow.

In a further preferred embodiment, the co-moving part of the printing system on at least two Hilfstranks, of which a first auxiliary tank serves as a single tank for supplying the at least one print head with ink.

In a further preferred embodiment, a second auxiliary tank is provided as an Austank for the at least one during the printing operation of the ink or ink ink flowed through printhead.

In a further preferred embodiment, in the case of a transport element for the print heads, which is rotatable about a vertical machine axis and designed, for example, as a rotor, the at least one auxiliary tank is arranged centrically with respect to the vertical machine axis and / or rotationally symmetrical.

In a further preferred embodiment, the at least one auxiliary tank is formed annular or circular cylindrical. In a further preferred embodiment, a line for feeding or discharging the printing ink or ink to or from the at least one auxiliary tank is arranged coaxially with the machine axis.

In a further preferred exemplary embodiment, when at least two auxiliary tanks are used, they are provided offset from one another in the direction of the machine axis or are arranged or formed such that the first auxiliary tank is enclosed by the second auxiliary tank.

In a further preferred embodiment, the moving or rotating part of the printing system is provided above the static part of the printing system or, with the exception of the at least one print head, the moving part of the printing system is surrounded by the static part of the printing system. concluded.

In a further preferred embodiment, the means for controlling the pressure of the ink or ink in the at least one auxiliary tank and / or in the at least one printhead in dependence on the rotational or rotational speed of the printhead are formed, preferably for compensating the ink or ink applied centrifugal forces and / or to compensate for acceleration and / or change of direction resulting and applied to the ink or ink forces.

In a further preferred embodiment, the static part of the printing system has at least one main tank for the printing ink or ink and means for refilling ink or ink and / or for conditioning the ink or ink, in particular for tempering and / or degassing and / or Filter the ink or ink.

In another preferred embodiment, the printing system for an ink or ink cycle is formed within the static portion of the printing system or ink supply system and / or for an ink or ink circuit which includes the static portion of the printing system as well as the moving or rotating portion of the printing system.

The invention further relates to a printing device for printing on bottles or similar containers with at least one peripherally drivable container conveyor and with a plurality of printing stations formed on the container conveyor on which the printing of the containers each with at least one according to the inkjet principle digital printhead of Printing system is done. The printing system is designed according to one of the previously described embodiments. The print heads are preferably provided on a movable transport element, preferably on a transport element which is movable about at least one vertical machine axis. Further preferably, the printhead having transport element of the container conveyor or independent of the container conveyor transport element.

In order to produce a multi-color imprint on the containers, it is preferable to provide a plurality of printing systems each associated with a color or a color set.

In a preferred embodiment, at least some of the printing systems assigned to different colors or color sets and their print heads are provided on a common or different transport elements.

Furthermore, at least two container transporters are preferably provided consecutively in a transport direction of the containers, wherein at least one printing system for printing the containers with a color or with a color set of a multi-color print is provided on each container conveyor.

Particularly preferably, each printing position is designed for a relative movement between the print head and the container. For the purposes of the invention, inert gas is understood as meaning gases which are very inert, ie. Participate in only a few chemical reactions. These are in particular CO2, N2 or sterile air.

Pulsation damper in the context of the invention are integrated in printing ink or ink-conveying lines integrated buffer elements having a receiving space for the ink or ink. Furthermore, these pulsation dampers can have a membrane which has a gas volume (eg air or nitrogen) from the receiving space for printing ink or ink. As a result, pressure fluctuations in the printing ink or ink-promoting lines or the print heads can be compensated. For the purposes of the invention, containers are in particular cans and bottles, in each case made of metal, glass and / or plastic, for example.

"End shooter printheads" in the sense of the invention are understood to mean printheads which each have only one connection via which the ink or ink is supplied at a predetermined pressure, for example with a slight negative pressure Ink is continuously applied to the printhead and can exit the printhead alone through the nozzles.

"Side-shooter printheads" in the sense of the invention are understood to mean printheads which have at least two ports through which the ink or ink is conveyed through the printhead in a cycle, preferably a transverse flow transverse to the nozzles of the printhead generated.

The term "substantially" or "approximately" or "approximately" in the sense of the invention means deviations from the exact value by +/- 10%, preferably by +/- 5% and / or deviations in the form of for the function insignificant changes.

Further developments, advantages and applications of the invention will become apparent from the following description of exemplary embodiments and from the figures. In this case, all described and / or illustrated features, in themselves or in any combination, are fundamentally the subject of the invention, regardless of their combination in the claims or their backward relationship. Also, the content of the claims is made an integral part of the description.

The invention will be explained in more detail below with reference to the figures of an embodiment. Show it: Fig. 1 in a very simplified representation and in plan view of a printing device of rotating design for printing on bottles or other containers;

Fig. 2 in a simplified functional representation essential elements of

Printing system of the printing apparatus of Figure 1 together with one of the print heads.

3 shows in a simplified representation and in vertical section by way of example the main tank of the printing system in a first embodiment;

4 shows by way of example a detail of the main tank according to FIG. 3 in FIG

Transition region between the first and second tank part;

5 shows in a simplified representation and in a vertical section by way of example the main tank of the printing system in a second embodiment;

6 shows, in a simplified representation and in vertical section, by way of example, the main tank of the pressure system in a third exemplary embodiment;

7 shows in a simplified representation and in vertical section by way of example the main tank of the printing system in a fourth embodiment;

Fig. 8 in a simplified representation and in vertical section the rotating and the static part of the printing system of Figure 2 with a main tank of FIG. 3.

9 shows in a simplified representation and in vertical section the rotating and the static part of the printing system of Figure 2 with a main tank similar to FIG. 5 ..;

Fig. 10 in a simplified representation and in vertical section the rotating and the static part of the printing system of Figure 2 with a main tank similar to Fig. 7.

Fig. 1 1 in a representation similar to Figure 2 shows a further embodiment of the printing system according to the invention;

FIG. 12 shows, by way of example, in perspective detail representation, the input or output tank of the printing system; FIG. Figure 13 is a schematic representation of the input and Austank of the rotating part of a printing system together with two print heads of this system. and

14 shows, by way of example, a schematic illustration of a cleaning system for cleaning a printhead.

In the figures, 1 is a rotary type printing apparatus for printing on bottles or the like containers 2 by using ink jet or ink jet printing heads 3. The print heads each have, for example, a plurality of nozzles 3.1 at each Printhead 3 are provided sequentially in a row in the vertical direction and are electrically controlled individually. The application of the ink to the nozzles 3.1 is carried out by appropriate control of electrodes, valves, piezo elements or the like.

In the illustrated embodiment, the printing apparatus 1 consists of a rotor 4 that revolves around a vertical machine axis MA, preferably continuously rotatable, on the circumference of which a plurality of printing stations 4. 1 are formed. Preferably, each printing station 4.1 is assigned in each case at least one print head 3, which is moved together with the respective printing station 4.1. The containers 2 to be printed are fed to the printing stations 4.1 via a container inlet 6 and subsequently moved together with the printing head 3 assigned to this printing station, the printing of the container 2 taking place during this movement. The printed containers 2 are taken from the respective printing station 4.1 at a container outlet 7.

The printing of the container 2 takes place at the printing stations 4.1 line by line by relative movement of the container 2 to the print head 3, in the illustrated embodiment in that each with its container axis in the vertical direction, ie parallel to the axis of rotation of the rotor 4 oriented container 2 during the printing is rotated controlled about its container axis. The printing device 1 according to the invention has, as shown in FIG. 2, a printing system 5 that consists of two components, namely the first, static printing system part designated 8 in FIGS. 2 and 3, which does not rotate in the direction with the rotor 4 Machine frame 9 of the printing device 1 is housed, as well as from the provided on the rotor 4 second, moving, in particular rotationally moving printing system part 10, which inter alia, the printheads 3 has.

The static printing system part 8 includes i.a. at least one main tank 100 for receiving a supply of ink, as well as all functional elements for conditioning the ink, i. et al a temperature module 12 for constant temperature control (heating or cooling) of the ink in the main tank 100 and a degasser 13 and a filter 14 in a conveyor and circulation pump 15 having and the main tank 100 enclosing the first ink circuit for constant temperature control, degassing and filtering the ink. The main tank 100, which is preferably partially filled with the printing ink, is subjected to a controlled pressure P100 during the printing operation, namely during the normal printing operation, for example with a pressure P100 which is slightly lower or higher than the ambient or atmospheric pressure.

The static pressure system part 8 further comprises a refill valve 16, via which the refilling of ink from cartridges 17 is possible. About a multi-way valve 18 which is arranged in the ink circuit of the static pressure system part 8 in the flow direction after the filter 14 and the main tank 100, or via a connected to the valve 18 line 19, the static part 8 of the pressure system 5 to a flow or Supply line 21 connected to valve 22 of the rotating part 10 of the printing system 5.

FIGS. 3 to 7 show a plurality of embodiments of the main tank 100 used in the static pressure system part 8. The main tank 100 is designed in several parts and comprises at least a first tank part 110 and a second tank part 120. The first tank part 110 forms a receiving space 11 for the printing ink or ink and thereby has a bottom portion 1 10a and a projecting conversion portion 1 10b. As a result, a cup-shaped first tank part 1 10 is formed, which is open on the opposite side of the bottom portion 1 10a. In the bottom section 1 10a, a supply line 1 10c for the recorded in the receiving space 1 1 1 ink or ink can be provided. The supply line 1 10c may be arbitrarily oriented differently from the vertical orientation shown. In particular, a tangential feed of the printing ink or ink relative to the central vertical axis MHA can also take place in order to bring about a circular flow of the printing ink or ink within the receiving space 11. Preferably, the first tank part 1 10 is rotationally symmetrical with respect to its central vertical axis MHA.

The second tank part 120 is arranged above the first tank part 110 and, as the upper tank part, closes the receiving space 11 1 formed in the first tank part 110. Preferably, the second tank part 120 is formed lid-like and causes together with the upper free end of the conversion section 1 10b a preferably fluid-tight closure of the receiving space 1 1 1. For this purpose, the second tank part has a surface-shaped cover section 120.1, which causes the cover of the receiving space 1 1 1.

The second tank part 120 further comprises a conduit 121 in the form of a tube. The line 121 forms a supply and / or return line for printing ink from the main tank 100. The line 121 penetrates the cover section 120.1 preferably at right angles and extends with a first, lower free end 121 .1 into the receiving space 1 1 1 of the first tank part 1 10 into it. Preferably, the lower free end 121 .1 of the line 121 is located at a small distance from the bottom portion 1 10a, in particular when the line 121 is used as a supply line for a withdrawal of the ink or ink from the receiving space 1 1 1.

The first tank part 1 10 is assigned to the static pressure system part 8, ie the first tank part 110 is immovable indirectly or directly opposite the machine. machine frame 9 held. The second tank part 120, however, is associated with the moving printing system part 10 and thus carries out the movement of the print head 3, in particular the rotary movement of the rotor 4, to which the print head 3 is arranged. Preferably, the second tank part 120 is mechanically coupled to the rotor 4, so that the movement of the rotor 4 is transmitted by this mechanical coupling to the second tank part 120. The mechanical coupling can take place by means of the at least one line 121 or by other or additional coupling means 140. The movement of the second tank part 120 can advantageously be used for mixing the ink or ink contained in the receiving space 1 1 1. For this purpose, 121 may be provided, for example, on the at least one line 121 not shown Rührabschnitte that set the ink or ink during movement of the second tank part 120 in motion. The stirring sections can be formed, for example, by laterally projecting surface sections, for example wing-like surface sections. This prevents sedimentation or separation of the liquid constituents without the provision of a separate circulation device. Preferably, at the upper free end of the conversion section 1 10b, which is opposite to the second tank part 120, a seal is provided which, despite the relative movement of the second tank part 120 relative to the first tank part 1 10 causes a fluid-tight seal of the receiving space 1 1 1. This seal can be formed for example by an O-ring of a flexible material, in particular rubber or of a sliding seal containing graphite or ceramic. Preferably, the seal is formed by a so-called. Gap seal or labyrinth seal, as shown for example in Figure 4 in more detail.

In order to form a gap seal or labyrinth seal, the conversion section 110a in the region of its free end, which is opposite the second tank part 120, can have a notch or a trench 1 10b.1, which is provided peripherally circumferentially and on both sides by remaining webs of the Wandlungsab- Section 1 10b is limited. The second tank part 120 may have a web 122 which interacts with the trench 1 10b. 1 or engages in this trench 1 10b. 1, and which is provided circumferentially on the underside of the second tank part 120. The trench 1 10b.1 or the web 122 in this case run rotationally symmetrical to the central vertical axis MHA of the first tank part 110 or of the second tank part. The material thickness of the web 122 is less than the width of the trench 1 10b.1, so that upon engagement of the web 122 in the trench 1 10b.1 left a gap on both sides. This gap may preferably be filled with a fluid, for example a solvent similar to the printing ink or ink received in the receiving space 11, or a pigment-free base fluid which forms the basis for the printing ink or ink used. Alternatively, the unoccupied by the ink or ink upper part of the receiving space 1 1 1 with a gaseous medium, such as an inert gas to a pressure slightly above the atmospheric pressure are brought, so that a blocking air flow in the gap between the wall portion 1 10b and the second tank part 120 is formed.

As an alternative or in addition to the previously described formation of a labyrinth seal, a sealing lip 123, for example a sealing lip 123 made of rubber, can be provided on the outer peripheral side in the transition region between the first and second tank parts 1 10, 120, remaining between the first and second tank parts 110, 120 Gap spans. In order for an undesired exit of the liquid received in the gap of the labyrinth seal liquid can be prevented or minimized. When using a blocking air flow, the sealing lip can minimize the escape of sealing air.

Preferably, the second tank part 120 is arranged adjustable in height relative to the first tank part 1 10, ie, the distance between the first and second tank part 1 10, 120 is formed variable. As a result, an optimum distance, in particular for the sealing of the main tank 100, can be achieved. The height adjustment can be achieved, in particular, by means of length-adjustable coupling elements 140 by means of which the second tank part 120 is held in relation to the rotor 4. In Fig. 5, another embodiment of a main tank 100 is shown. In the following, only the differences from the previously described embodiment will be explained. Incidentally, the above explanations also apply to this and the following embodiments (FIGS. 6 and 7).

The essential difference of the exemplary embodiment according to FIG. 5 is that the first tank part 110 is annular, in particular annular. Apart from the supply line 1 10c, the first tank part 110 thus has a rotationally symmetrical structure with respect to the central vertical axis MHA. In addition, the receiving space 1 1 1 itself has an annular or annular shape, that is, the receiving space 1 1 1 is also rotationally symmetrical with respect to the central vertical axis MHA. Due to the ring-like structure of the first tank part 1 10 1 10 a concentric opening 1 14 is formed in this first tank part, which extends coaxially with the central vertical axis MHA.

Preferably, the second tank part 120 also has an opening 124, so that the second tank part 120 is annular or annular. The opening 124 is preferably likewise provided concentrically on the second tank part 120, specifically in such a way that, when the second tank part 120 is arranged on the first tank part 110, a continuous opening is formed through the main tank 100 through the openings 1 14, 124.

When the main tank 100 is arranged in the static pressure system part 8 such that the vertical machine axis MA coincides with the central vertical axis MHA, the openings 1 14, 124 can be used to pass further lines, for example electrical lines or fluid lines, between the static pressure system part 8 and the moving pressure system part 10 be used. Alternatively or additionally, it is possible to place drive means in the region of the opening 14, in particular drive means for driving the rotor 4 of the printing device 1.

In the exemplary embodiment in FIG. 5, a wreath-shaped distributor 130 is provided on the upper side of the line 121. This coronal manifold can For example, have a tubular ring 130.1, in which the upper free end 121 .2 of the line 121 opens, in such a way that the interior of the ring 130.1 is fluid-tightly connected to the interior of the conduit 121. At the ring 131 .1 a plurality of branch points 130.2 may be formed, which are formed for example by pipes 130.3 opening into the interior of the ring 130.1. Through the tubes 130.3, the respective printheads 3 can be supplied with the ink or ink. By coupling the distributor 130 with the second tank part 120 via the line 121, the distributor 130 is also moved along, ie the distributor 130 is likewise assigned to the moving pressure system part 10.

FIG. 6 also shows, in a modification of the previously described exemplary embodiment according to FIG. 5, a main tank 100 of ring-shaped or circular-shaped first and second tank parts 110, 120. The first tank part 110 has a plurality of chambers 12 , 1 13, so that a plurality of receiving spaces 1 1 1, 1 1 1 'in the first tank part 1 10 are formed, which are fluid-tightly separated from each other by an intermediate conversion 1 15. To fill the respective chambers 1 12, 1 13 separate supply lines 1 10c, 1 10c 'are provided, the supply line 1 10c into the chamber 1 12 and the supply line 1 10c' in the chamber 1 13 opens. Preferably, the chambers 1 12, 1 13 are concentric with each other, in particular such that the chamber 1 12 an inner chamber and the chamber 1 13 forms an outer chamber surrounding the inner chamber 1 12 circumferentially. It is understood that in deviation from the embodiment shown embodiments with more than two chambers 1 12, 1 13 are possible.

In the exemplary embodiment shown, the second tank part 120 has at least two lines 121, wherein the lines 121 are arranged on the cover section 120.1, which extends into the chamber 1 12 a first line into the chamber 1 12 and a second line. As a result, via the lines 121, a separate removal of the ink contained in the chambers 1 12, 1 13 ink or ink possible. FIG. 7 shows a further variant of the main tank 100, in which a multiplicity of lines 121 are provided in a modification of the previously described embodiment according to FIG. 6, wherein a first part of lines into the chamber 1 12 and a second part of lines into the chamber 1 13 extends. Through the lines 121 individual outlets for each printhead 3 are formed.

By referring to Figures 2 and 8, the printing system 5 will be described in more detail below. The moving printing system part 10 includes i.a. two auxiliary or auxiliary tanks 23 and 24, of which the auxiliary tank 23 serves as a tank 23 or as a source for the printing heads 3 supplied ink or ink and of which the auxiliary tank 24 as Austank or as a sink for receiving the not required for printing, the print heads 3 flows through the ink used. The two auxiliary tanks 23 and 24 are each made circular and central, i. Coaxially with the machine axis MA and in the vertical direction one above the other provided on the rotor 4, namely the auxiliary tank 23 above the auxiliary tank 24. The individual print heads 3 are arranged distributed around the auxiliary tanks 23 and 24. The supply line 21 opens via the valve 22 into the auxiliary tank 23. The auxiliary tank 23 is connected in each case via a line 25 to an inlet serving as the inlet of the respective print head 3. A serving as an outlet port of each printhead 3 is connected via a line 26 with pressure reducer 27 to a multi-way valve 28, via which either a connection of the line 26 to the auxiliary tank 24, a connection between the auxiliary tank 24 and the line 21 or the line 19th or a connection between the line 26 and the line 21 or with the line 19 is possible. In normal pressure operation, the valve 28 is controlled so that there is a connection between the conduit 26 and the auxiliary tank 24 via this valve. In the illustrated embodiment, the two auxiliary tanks 23 and 24 continue to be identical.

Each auxiliary tank 23 and 24 has means with which the pressure in the auxiliary tank 23 and 24, which is partially filled during the printing operation in each case with the ink, and In particular, the pressure in the lines 25 and 26 and thus at the terminals of the print heads 3 is set exactly so that the pressure P23 in the auxiliary tank 23 is slightly larger than the pressure P24 in the auxiliary tank 24, but the pressure P23, for example, is slightly smaller as the atmospheric pressure. By this pressure control on the one hand ensures that the print heads 3 are flowed through during the printing operation of the ink, that is not required for the printing amount of each printhead 3 via the line 25 supplied ink the print head 3 is discharged through the line 26 is discharged , The volume flow of the ink to each print head 3 from the auxiliary tank 23 and from each print head 3 to the auxiliary tank 24 can be adjusted by appropriate selection of the pressures P23 and P24.

In order to achieve independent or substantially independent conditions during the printing operation of the rotational speed of the rotor 4, not only the two auxiliary tanks 23 and 24 are centrally located on the rotor 4 and the printing heads 3 are respectively around the auxiliary tanks 23 and 24 in the same radial Provided distance from these auxiliary tanks, but also leading to the printheads 3 and individually provided for each print head 3 lines 25 and 26 are routed to the rotor 4 for each print head 3 in the same way, for example, such that these lines radially or substantially radially to the vertical machine axis MA run.

The auxiliary tanks 23 and 24 are further equipped with means which ensure an exact filling level of the printing ink in each auxiliary tank 23 or 24 during operation of the printing device 1. In the illustrated embodiment, these means are formed by the fact that inside each annularly shaped auxiliary tanks 23 and 24, an annular barrier or overflow 29 is provided which concentrically surrounds the machine axis and the serving for receiving the ink tank interior 23.1 and 24.1 of a likewise in each auxiliary tank 23 and 24 formed annular collecting space 23.2 and 24.2 separates, which serves to collect excess ink. The collection rooms 23.2 or 24.2 are provided on the inside, ie enclosed by the associated tank interior 23.1 or 24.1.

The printing system is operated so that in each auxiliary tank 23 and 24 constantly a certain flow of ink from the tank interior 23.1 and 24.1 via the overflow 29 in the associated plenum 23.1 and 24.1 flows. The plenums 23.2 and 24.2 are connected to the main tank 100 in connection, in the illustrated embodiment such that the plenum 23.2 is connected via a line 30 and a pressure reducer, not shown, with the plenum 24.2 and the latter via a line 31 and a control valve 34 is connected to the main tank 100.

During operation, the printing system is further controlled, including by appropriate control of the pump 15, the valves 18, 22 and 34, that not only the main tank 100 filling height or level control is partially filled with the ink, ie printing ink from the on the Refill valve connected cartridge 17 is refilled via this refill valve, the pump 15, the degasser 13, the filter 14 and the valve 18 in the main tank 100 when the ink level in the main tank 100 falls below a predetermined level, but the system is also operated, that also each collecting space 23.2 and 24.2 level or filling level controlled is filled with ink. For this purpose, both the main tank 1 1, as well as to the collecting spaces 23.2 and 24.2 level sensors 35 (main tank 1 1) and 36 (collecting spaces 23.2 and 24.2) are provided. For emptying the auxiliary tanks 23 and 24 or the tank interior spaces 23.1 and 24.1 each tank is provided with a drain valve 32, via which the tank interior 23.1 or 24.1 connected to the outlet of the associated plenum 23.2 or 24.2 or the corresponding line 30 and 31 respectively can be, but which is closed during normal operation of the printing device. During the printing operation of the printing apparatus 1, the ink circulates in the printing system 5 in two circuits, in which the pump 15, the degasser 13, the filter 14 and the main tank 100 enclosing the first ink circuit of the static or stationary part 8 and in a second ink circuit, which includes the static part 8 and the rotating part 10 of the printing system and also the print head 3. In this second ink cycle, the ink flows through, for example, starting from the auxiliary tank 23, the printheads 3, then passes through the valve 28 back to the auxiliary tank 24 and from this auxiliary tank via the overflow 19 and via the plenum 24.2 to the main tank 1 1, from the the ink is then returned via the pump 15, the degasser 13, the filter 14 and the correspondingly adjusted valve 18, the connected line 19 and the line 21 to the auxiliary tank 23. Both ink circuits thus include the controlled main tank 100, the degasser 13 and the filter 14, so that the ink in these printing ink circuits constantly conditioned, dhua is maintained at a required for optimum printing quality and temperature level. The control of the printing device 1 and the printing system 5 of this machine can be carried out so that during the printing operation both ink cycles are simultaneously flowed through by the ink. However, it is also possible to control the printing system 5 so that only the second, the static part 8 and the rotating part 10 enclosing ink cycle is at least primarily activated during the printing operation, while the first ink circulation of the printing system to a faster and more intensive conditioning the ink is then activated when just no additional ink to the auxiliary tank 23 must be promoted. The two-part design of the printing system, ie the separation into the static part 8 and the rotating part 10 has considerable advantages:

Thus, in the static part 8, the pump 15 as well as all functional elements can be accommodated, which are required for the conditioning of the ink, whereby the number of components on the rotor 4 and the local construction volume can be reduced.

Mechanical vibrations caused by the pump 15 and other motor-driven functional elements (eg also vacuum pumps) or by their drive, which (vibrations) can affect the printing result, are kept away from the rotor 4.

About the refill valve 16 can be easily refilled new ink from the respective cartridge 17 in the printing system, wherein the refilled ink is pretreated at least in the degasser 13 and the filter 14 before it enters the printing system 5.

By using the two auxiliary tanks 23 and 24, which are arranged centrally on the rotor 4 and rotationally symmetrical with respect to the vertical machine axis, a homogeneous distribution results, in particular also pressure distribution of the ink at the terminals of the print heads 3.

By controlling the pressures P23 and P24, taking into account the arrangement of the spinning heads 3 with respect to the auxiliary tanks 23 and 24 and depending on the rotational speed of the rotor, both the pressure of the ink at the printheads 3 and at the local nozzles 3.1, as well as the flow rate of the ink are controlled by the print heads 3 and regulated.

Through the use of the auxiliary tanks 23 and 24, the printheads 3 are further decoupled from any pressure fluctuations or thrusts when supplying and / or discharging the ink, thereby avoiding adverse effects on the quality of the respective imprint by such pressure fluctuations.

Due to the level control of the ink in the tank interior spaces 23.1 and 24.1 continue to give constant pressure conditions at the terminals of the printheads 3 and thus a reproducible optimal print quality.

Due to the circulation of the printing ink, in particular in the rotating part 10, in particular unwanted drying of the printing ink and the resulting malfunctions are avoided.

In the region of the discharge of the ink from the respective collecting space 23.2 and 24.2 via the line 30 and 31 of the rotational speed of the rotor 4th To achieve independent conditions, the lines 30 and 31 and their connections are each arranged coaxially with the machine axis MA. The auxiliary tanks 23 and 24, in turn, form the tank interior 23.1 and 24.1, which lie radially outward in relation to the machine axis MA, and the collecting chamber 23.2 or 24.2 located inwardly relative to the machine axis MA.

Of course, it is possible to rinse and clean the printheads 3 and the nozzles 3.1 in a maintenance cycle (maintainer cycle). For this purpose, by appropriate control of the printing system 5 and in particular the various valves pumped ink at elevated pressure through the printheads 3 or funded, from the static part 8 via the line 19 to the rotating part 10 and there, for example via the line 26 to the individual print heads 3, at the nozzles 3.1, at least part of the under high pressure funded ink emerges for rinsing and cleaning.

FIG. 9 shows, in a representation comparable to FIG. 8, a further exemplary embodiment of the printing system according to the invention. In this case, there is an annular design of the main tank 100 use, which has a plurality of lines 121 for supplying ink or ink. The lines 121 are connected to the tank 23 through which the ink or ink is supplied to the printheads 3. Further, a return line 40 is provided, which leads from the Austank 24 to the main tank 100 and allows a return flow of the ink or ink, in particular for treatment purposes. For mechanically coupling the second tank part 120 with the rotor 4, coupling means 140 shown schematically in FIG. 9 are provided, which firmly connect the second tank part 120 to the rotor 4, so that the second tank part 120 is simultaneously moved when the rotor 4 rotates. In addition, an inert gas feed line 39 can be provided, by means of which an inert gas can be fed into the receiving space 11 of the main tank 100. This inert gas can be used, for example, to generate a barrier air flow is, which exits through a provided between the first and second tank part 1 10, 120 gap and thereby prevents ingress of undesirable substances in the receiving space 1 1 1. FIG. 10 shows a further exemplary embodiment of the pressure system 5 according to the invention. The main tank 100 used is a tank with a plurality of chambers, as previously described with reference to FIG. In the exemplary embodiment shown, the main tank 100 has two chambers 1 12, 1 13, wherein the chamber 1 13 extending around the outside of the chamber 1 12 forms a flow chamber in which conditioned or tempered printing ink or ink is stored. The reaching into this chamber 1 13 lines 121 form supply lines for supplying the print heads 3 with ink or ink. The reaching into the chamber 1 12 lines 121 form return lines in which reprocessed ink or ink in the chamber 1 12 is traceable. The chamber 1 12 may be connected via a drain 1 16 with a reprocessing device 50, in which, for example, the ink or ink degassed, filtered and subjected to other processing steps. Tempering means 68 can be provided in the discharge line, which effect, in particular, a cooling of the printing ink or ink. The reconditioning device 50 is further connected via a supply line 1 10c to the chamber 1 13, which contains the recycled ink or ink. Tempering means 68, via which, in particular, heating of the printing ink or ink is possible, can likewise be integrated into this feed line 1 10c.

For the mechanical coupling of the second tank part 120 to the rotor 4, coupling means 140, which are shown schematically in FIG. 10, connect the second tank part 120 to the rotor 4 so that the second tank part 120 is simultaneously moved when the rotor 4 rotates. These coupling means 140 are designed to be adjustable in height, so that a height-adjustable suspension of the second tank part 120 relative to the rotor 4 is effected.

Another essential difference of the embodiment shown according to FIG. 10 compared with the exemplary embodiments described above is that in that instead of the auxiliary tanks 23, 24 pulsation dampers 41, 42 are provided. In this case, each print head 3 is preferably associated with a pair of pulsation dampers 41, 42, namely a pulsation damper 41 in the direction of flow of the ink or ink in front of the print head 3 and another pulsation damper 42 in the direction of flow of the ink or ink after the print head 3 The pulsation dampers 41, 42 each form a reservoir for the ink or ink, which is considerably smaller than the receiving space of the auxiliary tanks 23, 24. Furthermore, the pulsation dampers 41, 42 contain a membrane, the interior of the pulsation damper in one of the printing ink or ink flows through the subspace and another subspace in which a gas is contained. As a result, pressure fluctuations in the line system for supplying or removing the printing ink or ink can be compensated or substantially minimized. Further preferred between the pulsation damper 41 and the print head 3, that is, a filter 43 provided in the ink inlet, can be filtered with the particles larger than a defined particle size of the ink or ink.

FIG. 11 shows an illustration like FIG. 2 of an alternative printing system 5a of a printing apparatus. The printing system 5a again consists of the stationary part 8a and the rotating part 10a, wherein the stationary part 8a is identical to the stationary part 8 of the printing system 5 of FIG. The rotating part 10a has on the rotatable about a vertical machine axis MA rotatably rotatable rotor digitally controllable printheads 3a, which operate in the same way as the printheads 3 by the ink-jet or ink jet principle and in each case a plurality of nozzles 3a.1 for controlled application of the ink provided (nozzles) in a vertical axis direction, ie in an axial direction parallel to the machine axis MA consecutively provided. Deviating from the printheads 3, the printheads 3a are formed as printheads with static ink or ink supply, ie. As so-called "end shooter printheads", each having only one port through which the printing dye with a predetermined pressure, for example with a slight negative pressure or overpressure is supplied. The rotating part 10a of the printing system again has the two auxiliary tanks 23 and 24, although only the auxiliary tank 23 or its tank interior 23.1 is connected to the single input of each print head 3a via a respective line 25 and an additional multiway valve 37 provided in this line , To the valve 37 and the line 26 is connected to the pressure reducer 27, which is connected directly to the line 21 to the line 19 in this embodiment. The auxiliary tank 24 is not used in this embodiment as a sink for receiving ink that was returned by printheads, but only the plenum 24.2 of the auxiliary tank 24 is for receiving the excess ink from the plenum 23.2 and for discharging this ink to the main tank 100th used the static part 8a.

In the printing system 5a are also two ink cycles possible, namely a first circuit within the static part 8a, which in turn includes the pump 15, the degasser 13, the filter 14 and the main tank 100 and a second ink circulation, the static 8a and the rotating part 10a. This second ink cycle then extends, for example, starting from the tank interior 23.1 of the auxiliary tank 23 via the local overflow 19 into the collecting space 23.2, from there into the collecting space 24.2, from there into the main tank 100 and from there via the pump 15, the degasser 13, the filter 14 and the lines 19 and 21 back to the auxiliary tank 23 and to the local tank interior 23.1.

Thus, also in the printing system 5a, the printing ink is constantly conditioned not only in the first ink circuit running solely on the static part 8a, but also in the second circuit which encloses both the static part 8a and the rotating part 10a of the printing system 5a. ie degassed, filtered and tempered, ie the respective requirements either heated or cooled. Above, it was assumed that the two, each identically designed and annular auxiliary tanks 23 and 24 are provided offset in the vertical direction, ie offset in the machine axis. Of course, other designs are conceivable. Thus, FIG. 12 shows a perspective view of a tank arrangement 38, which forms the two individual tanks 23a and 24a, which in turn are of annular shape, the machine axis MA concentrically encircling, but unlike the above-described embodiment, are not offset against one another in the direction of the machine axis MA but are arranged in such a way that a single tank, for example, the auxiliary tank 23 a, the auxiliary tank 24 a annularly encloses. Through the overflow 29a, the auxiliary tanks 23a and 24a are again in a tank interior 23a.1 or 24a.1 and a collecting space 23a.2 or 24a.2. FIG. 13 again shows, in a very simplified representation, the rotating part 10b of a printing system 5b having the printing heads 3, together with the centrally arranged auxiliary tanks 23b and 24b offset in the direction of the machine axis MA, of which the auxiliary tank 23b in turn controls the source of ink. or the Eintank for the printheads 3 and the auxiliary tank 24b, the ink reservoir (drain) and the Austank for the printheads 3 form. Only two printheads 3 are shown. In fact, the printing system has a plurality of printheads 3. Although the two auxiliary tanks 23b and 24b are arranged centrically with respect to the machine axis MA and rotationally symmetrical about this machine axis MA, that is circular cylindrical, the two auxiliary tanks 23b and 24b do not have the overflow 29 and the collecting space formed thereby. The parabolic course of the printing ink level (convex meniscus) produced by the rotational movement of the rotor is clearly illustrated in FIG. Changing pressure conditions due to a changing rotational speed of the rotor are adjusted by regulating the pressures P23b and P24b in the auxiliary tanks 23b and 24b and the differential pressure between these auxiliary tanks. fits or compensates, so that a constant flow rate of the ink through the printheads 3 and a constant pressure, for example, a constant or stable negative pressure (meniscus negative pressure) is reached at the nozzles 3.1 of the printheads 3.

It has heretofore been assumed that the respective printing apparatus 1 comprises a printing system 5, 5a or 5b which is capable of printing the containers 2 with a single ink or ink, i. with the ink or ink of a single color allows. To produce a multi-color print with multiple color sets, a plurality of printing devices 1 are then sequentially provided in a system, wherein in each printing device then a color set of the respective multi-color print is generated. At least in the further printing devices following the first printing device, the printing positions 4.1 for aligning the respective container 2 are formed on a marking provided or applied to the container prior to the actual beginning of printing so as to apply the individual color sets forming the multicolor printing in the correct position guarantee.

In principle, it is also possible to provide a plurality of printing systems 5, 5a or 5b for a plurality of inks different in color on a single printing device so as to provide the respective container 2 at each printing position 4.1 already complete with a multi-color imprint and / or with multiple color sets of one at a further printing device completed multicolor printing.

14 shows a printhead 3 which operates according to the so-called "end-shooter principle." In the case of this type of printhead 3, there is no ink circuit in which the printhead is integrated, as is the case, for example, in the previously described exemplary embodiments 2, 8, 9, 10 and 13, but the ink is continuously under pressure at the printhead and can exit the printhead alone via the nozzles 3.1 Printing ink through a rear Kannnner the printheads 3 possible, ie no transverse to the individual channels in the respective nozzles 3.1 running flow.

Particularly in the case of these "end-shooter" principle printheads 3 but also optionally in the cross-flow, according to the so-called. "Side-shooter" - principle working printheads, in which a cross flow of ink through a rear chamber of the printheads. 3 is ensured, means may be provided for performing a cleaning process for the printheads 3. In particular, these means for carrying out the cleaning process comprise a tank 60 containing a cleaning fluid. The cleaning fluid can be formed by a solvent or a printing ink-forming ink base fluid without pigments and without UV-reactive components (inhibitors). The receiving space of the tank 60 is fluidly connected via a line 61 to the at least one print head 3, preferably to all print heads 3 of the printing system 5. In this line, preferably a pump 62 and a multi-way valve 63 is integrated via which instead of the cleaning fluid, a gaseous medium in the conduit 61 can be introduced.

For picking up the cleaning fluid discharged by the print head 3 via the nozzles 3.1, a cap 64 is arranged in front of the print head 3 and preferably covers the entire exit area at which the cleaning fluid discharged from the print head 3 emerges. The cap 64 is fluidly connected to the tank 60 by means of a return line 67, in which preferably a filter unit 65 and further preferably a pump 66 is integrated. Furthermore, a treatment unit for the treatment of the cleaning fluid can be provided in the circuit.

By means of the above-described cleaning cycle, it is possible to apply the cleaning fluid to the individual print heads 3 of the printing system 5, to apply this cleaning fluid through the nozzles 3.1 in order to flush the print head 3 and thereby clean it of printing ink residues. After the cleaning fluid has been dispensed, it is collected by the cap 64 and if desired, after being filtered through the filter unit 65 and optionally treated, returned to the tank 60 for reuse.

The tank 60 can in this case be formed by a separate tank, which is preferably arranged in the static pressure system part 8. Alternatively, the tank 60 may be integrated into the main tank 100, in particular such that a chamber 1 12, 1 13 of the main tank 100 is provided for receiving the cleaning fluid. In the event that a separate tank 60 is used, the cleaning process can be performed either with a fixed rotor 4, so that a fixed connection to be made for the cleaning process between the static pressure system part 8 and the moving pressure system part 10 is possible. Alternatively, a separate rotary distributor may be used to establish communication between the static pressure system part 8 and the moving pressure system part 10. In the case where the tank 60 is integrated with the main tank 100, a separate rotary distributor is not needed because the coupling of the moving pressure system part 10 to the static pressure system part 8 is effected by the main tank 100 with the second tank part 120 being moved.

Thus, the invention also includes a very advantageous method, namely the printing inks, which tend to segregate, very easy and effective to circulate and keep in motion by the contents of the tanks 100 through the free ends of the extraction lines 121, the in extend the stationary tank part 1 10 and move with the rotating tank part 120, is constantly stirred and mixed. In order to ensure undesirable uptake and dissolution of gases in the printing ink or ink, temporarily or permanently, a buffer gas, in particular an inert or sterile gas, can be conducted into the headspace of the tank 100, preferably via a passage in the wall of the stationary tank part 1 10 takes place. Ideally, therefore, the additional circulation, via an external pump, for example, omitted.

The invention has been described above by means of exemplary embodiments. It is understood that numerous changes and modifications are possible without thereby departing from the inventive concept underlying the invention.

It has been assumed above that the rotating part 10, 10a, 10b of the printing system is located above the static part 8, 8a of the printing system. Basically, to achieve a compact design as possible, the possibility of the static part of the printing system in such a way that it completely or almost completely encloses the moving or rotating part of this system, so that ultimately only the printheads protrude beyond the top of the printing system.

It has also been assumed above that on the rotor 4, which initially holds the transport element for the containers 2, i. forms the container conveyor, and the print heads 3 and 3a are provided, so the rotor 4 at the same time also the printheads 3 and 3a moving transport element. However, embodiments are also conceivable in which the print heads 3 and 3a are each provided with at least one color or a color set of a multicolor print on a separate transport element (print head transport element) moved or rotated about the vertical machine axis MA.

In particular, the regulation of the pressures P23 and P24 is effected, for example, also as a function of the rotational speed and / or acceleration of the rotor 4 in such a way that centrifugal forces exerted on the ink or ink by the pressure control are compensated. LIST OF REFERENCE NUMBERS

1 printing device

2 containers

3, 3a printhead

3.1, 3a.1 nozzle

4 rotor

4.1 printing station

5, 5a, 5b printing system

6 container inlet

7 container outlet

8, 8a static pressure system part

9 machine frame

10, 10a, 10b moving printing system part

12 temperature module

13 degasser

14 filters

15 pump

16 refill valve

17 ink or ink cartridge 18 multiway valve

19 line

21 line

22 valve

23, 23a, 23b auxiliary tank or tank

23.1, 23a.1 Tank interior

23.2, 23a.2 Collection room

24, 24a, 24b auxiliary tank or Austank

24.1, 24a.1 Tank interior

24.2, 24a.2 collection room

25, 26 line

27 pressure reducer 28 multiway valve

29, 29a overflow

30, 31 line

32 emptying valve

34 valve

35, 36 level sensor

37 multiway valve

38 tank arrangement

39 inert gas supply

40 return line

41.42 Pulsation damper

43 filters

50 reprocessing device

60 tank

61 line

62 pump

63 multiway valve

64 cover cap

65 filter unit

66 pump

67 return line

68 tempering agent

100 main tank

110 first part of the tank

110a floor section

110b wall section

110b.1 ditch

110c, 110c 'supply line

111, 111 'recording room

112 chamber

113 chamber 1 14 opening

1 15 intermediate wall

1 16 process

120 second tank part

120.1 cover section

121 line

121 .1 lower free end

121 .2 upper free end

122 footbridge

123 sealing lip

124 opening

130 distributors

130.1 ring

130.2 Junction 130.3 Pipe

140 coupling agent

MA vertical machine axis MHA middle vertical axis

P100, P23, P24 pressure

P23b, P24b pressure

Claims

claims

1 . Printing system for printing on bottles or similar containers (2), having a moving printing system part (10) on which at least one digital printhead (3, 3a) which operates according to the ink jet principle and is movable along a transport path for the containers (2), preferably revolving. for printing on the respective container (2) arranged at a printing station (4.1), and a static printing system part (8) not moving with the print head (3), comprising at least one tank (100) for receiving the print head (3 ) to be supplied ink or ink, characterized

that the tank (100) is designed in several parts, wherein a first tank part (1 10) is arranged statically and a second tank part (120) with the moving pressure system part (10) mitbewegbar formed, wherein the first tank part (1 10) as a lower Tank part forms the receiving space for the ink or ink to be stocked.

2. Pressure system according to claim 1, characterized in that the second tank part (120) as the upper part of the tank, the first tank part (1 10) closes.

3. Pressure system according to one of the preceding claims, characterized in that the second tank part (120) as the first tank part (1 10) occlusive cover is formed.

4. Pressure system according to one of the preceding claims, characterized in that the first and second tank part (1 10, 120) are fluid-tightly interconnected.

5. Pressure system according to claim 4, characterized in that between the first and second tank part (1 10, 120) is provided as a seal, a ring seal or a sliding seal.

6. Drucksystenn according to claim 4 or 5, characterized in that between the first and second tank part (1 10, 120) as a gasket, a gap seal, in particular a liquid-filled gap seal is provided.

7. Pressure system according to one of claims 1 to 6, characterized in that the interior of the tank (100) is acted upon with an inert gas to generate by a between the first and second tank part (1 10, 120) gap formed a barrier gas flow ,

8. Pressure system according to one of the preceding claims, characterized in that the second tank part (120) relative to the first tank part (1 10) is designed to be height adjustable.

9. Pressure system according to one of the preceding claims, characterized in that the first and / or second tank part (1 10, 120) is annular, in particular annular with a central opening (1 14, 124) is formed.

10. Pressure system according to one of the preceding claims, characterized in that the second tank part (120) has at least one tubular duct (121), one free end of which is formed by the first tank part (1 10) receiving space (1 1 1 ) or that the second tank part (120) has a plurality of angularly offset from each other staggered, tubular formed lines (121), the free ends in the first of the tank part (1 10) formed receiving space (1 1 1) extend.

1 1. Printing system according to claim 1 1, characterized in that the free end of the at least one line (121) has a laterally projecting Rührab- cut or body or is formed.

12. Printing system according to one of the preceding claims, characterized in that the second tank part (120) at least one in the receiving having space (1 1 1) of the first tank part (1 10) reaching into the stirring section.

13. Printing system according to one of the preceding claims, characterized in that the first tank part (1 10) has a plurality of separate chambers (1 12, 1 13) for receiving ink or ink.

14. Printing device for printing on bottles or similar containers with at least one circumferentially drivable container conveyor (4) and with several on the container conveyor (4) formed printing stations (4.1), where the printing of the container (2) each with at least one of the inkjet principle working digital printhead (3, 3a) of a printing system (5, 5a, 5b), characterized in that the printing system according to one of the preceding claims 1-14 is formed.

15. A method for mixing and stirring of printing ink or ink when printing bottles or similar containers, which with at least one circumferentially driven container conveyor (4) and with several on the container conveyor (4) formed printing stations (4.1) are moved, where the Printing the container (2), in particular in each case with at least one operating according to the inkjet principle digital printhead (3, 3a) of a printing system (5, 5a, 5b), wherein the printing ink in a printing ink or ink comprises first tank (100) for at least a plurality of Druckköpf (3, 3a) is stored and stored upstream, characterized in that the tank (100) is formed in several parts, wherein a first tank part (1 10) is arranged statically and a second tank part (120) is rotated or rotated , wherein line (121) or at least a partial length of the second part of the tank (120) in the first tank part (1 10) protrude and with the second Ta nkteil (120) are connected so that the ink or ink in the tank part (1 10) through which the lines (121) or at least a partial length of the free ends of the lines (121) mixed and stirred.

16. The method according to claim 15, characterized in that the second tank part (120) with the moving pressure system part (10) is moved, wherein the first tank part (1 10) as a lower part of the tank forms the receiving space for the ink or ink to be stored ,

17. The method according to claim 15 or 16, characterized in that the printing system according to one of the preceding claims 1-14 is formed.