DE102021105521A1 - Device and method for coating containers - Google Patents

Abstract

Device (1) for coating containers (10) with at least one coating station (20a, 20b, 20c...) and a transport device (2) which transports the containers (20a, 20b, 20c...) to be coated to this coating station (20a, 20b, 20c...). 10), the coating station having a first electrode (22) and a second electrode, at least one of these electrodes being insertable into the containers (10), the coating station (20a, 20b, 20c...) having a vacuum chamber (12 ) within which at least a part of the container to be coated and the electrodes (22, 24) are arranged, as well as a vacuum generating device (4) which generates the vacuum in this chamber. According to the invention, the device (1) has a cooling device (6) for cooling the electrodes (22, 24) that can be inserted into the containers (10).

Description

The present invention relates to a device and a method for coating containers and in particular for coating plastic containers. Such devices and methods are known from the prior art. In the production of plastic containers, the problem sometimes arises that substances from the filling can diffuse into or through the wall of the container. For this reason it is known to coat the inner walls of the containers and in particular to coat them with plasma.

A container coating system, BBA for short, is known from the internal prior art of the applicant. A thin SiOx layer is deposited on the inner wall of the container in a vacuum using plasma.

This is a machine capable of coating containers on the inside. These are preferably plastic containers. The containers are equipped with a thin barrier layer on the inside. This significantly reduces gas exchange through the plastic wall (e.g. CO2 exit and O2 entry). The layer can be an extremely thin glass layer, for example. To produce the coating, the treatment chamber including the container is first evacuated. Various gases are then fed into the interior of the bottle. The coating process is then initiated by generating a plasma inside the bottle. To do this, one or two electrodes are inserted into the container, to which a high voltage is applied.

The corresponding coating process is as follows:

First, an uncoated container and in particular an uncoated bottle is positioned over a gas lance. An air pressure in the coating chamber is then pumped down to an absolute pressure of approximately 1 mbar, preferably by means of one or more vacuum pump stages. Various gas mixtures (G1/G2/G3...) are fed into the container one after the other, for example through a nozzle, and a high voltage with specific frequencies is applied to the electrodes while they are being fed.

The power and pulse periods (pulse duration, pulse pause) are preferably varied. The gases are converted in the plasma. Some of the particles or molecules “stick” to the surface of the bottle wall and form a barrier layer. Another part of the particles is sucked off by means of a vacuum pump. The coating chamber is then preferably ventilated. The coated bottle is transported away.

When the plasma burns and the gases are converted, a high temperature of a few thousand °C is created briefly inside the bottle. This temperature heats up the bottle wall on the one hand and the electrode(s) on the other. The temperature of the bottle or container at the beginning of the process (before the plasma ignites) is relatively low because a fresh, cooled bottle enters the process chamber each time.

On the other hand, the lance temperature increases over time after several cycles / containers because the heat cannot be completely dissipated in short container changeover times. When the next uncoated container is positioned over the lance (or over the electrodes), heat transfer takes place from the hot lance to the bottle wall. The excess heat causes the bottle wall material to shrink excessively and other side effects that degrade bottle quality and barrier layer effectiveness.

The present invention is therefore based on the object of making the plasma coating process more efficient and, in particular, of avoiding excessive heating of the containers. These objects are achieved by an apparatus and a method according to the independent patent claims. Advantageous embodiments and developments are the subject of the dependent claims.

A device according to the invention for coating containers has at least one coating station and at least one transport device, which feeds the containers to be coated to this coating station and wherein the coating station has a first electrode and a second electrode, wherein at least one of these electrodes can be inserted into the containers, wherein the Coating station has a vacuum chamber within which at least part of the container to be coated and the electrodes are arranged at least temporarily, and a vacuum generating device which generates the vacuum in this chamber.

According to the invention, the device has a cooling device for cooling the electrode or electrodes that can be inserted into the containers.

Both electrodes can preferably be inserted into the containers. In this case, it is possible for the two electrodes to be arranged on a carrier and can be inserted into the container by a relative movement between the carrier and the container.

In this case, a large number of coating stations is preferably provided. It would be possible for each coating station to be assigned a vacuum chamber, but it would also be possible for a number of coating stations to be arranged in a common vacuum chamber. Several transport devices can also be provided, which in particular transfer the containers to one another.

The electrodes are preferably embodied as lances and/or the electrodes form a lance-like structure together with a tube, described in more detail below, via which free-flowing media for the coating can be introduced into the container.

(Lance) cooling is proposed in order to minimize and/or reduce the heating of the bottle or container by the hot parts of the lance. The electrodes and preferably also the nozzle (gas tube) are cooled and thus much less heat is transferred from the electrode and/or from the nozzle into the bottle wall material.

The high voltage applied to the electrodes should preferably not be transferred to the cooling medium. Electrical insulation between the electrode and the heat sink is preferably proposed, as described in more detail below.

The electrode preferably has an outside diameter of 2 mm to 7 mm and particularly preferably an outside diameter of approx. 2.5 mm, which, with a limited length, represents a relatively small surface area and thus an effective contact area for cooling. So that the thin electrode can nevertheless be cooled effectively, an enlargement of the effective surface for cooling is proposed in a preferred embodiment.

The cross-sectional area can be circular, but other geometries would also be conceivable, such as oval geometries, curved geometries or polygonal geometries.

• So erfolgt eine Minimierung des Flaschenschrumpfens. Weiterhin kann das Plasma mit mehr Leistung versorgt werden, was u. U. vorteilhaft für den Prozess ist. Daneben ergeben sich auch mehr Freiheitsgrade für die Prozesseinstellung. Weiterhin kann die Barrierewirkung der SiOx-Schicht verbessert werden und bevorzugt kann im Ergebnis auch die Qualität der Flasche verbessert werden.

By reducing the temperature of the electrode(s) and nozzle, the temperature of the bottle wall material is also increased less, which brings several advantages:

• This minimizes bottle shrinkage. Furthermore, the plasma can be supplied with more power, which may be advantageous for the process. In addition, there are also more degrees of freedom for the process setting. Furthermore, the barrier effect of the SiOx layer can be improved and the quality of the bottle can preferably also be improved as a result.

In a preferred embodiment, the coating station has a tube which can be inserted into the containers and by means of which a medium, in particular a gaseous medium, can be fed to the container.

In a further preferred embodiment, the device has a cooling device for cooling the tube. This cooling device can have a cooling medium.

This tube can preferably be introduced into the container together with the electrodes, and the tube is preferably mechanically coupled to the electrode(s).

Preferably at least one plasma gas and preferably a plurality of plasma gases are introduced into the container via the tube. At least one electrode is preferred and both electrodes are particularly preferred outside the tube. The tube is preferably made of an electrically insulating material.

The tube preferably extends in a longitudinal direction, which is in particular also the longitudinal direction of the container to be coated. The at least one electrode preferably extends, and particularly preferably both electrodes, in the said longitudinal direction extend further than the tube.

In a further preferred embodiment, the cooling device cools both the electrode and said tube or nozzle.

In a further preferred embodiment, the cooling device has a heat sink that cools the electrodes. In this case, it is possible for the electrodes and/or the nozzle or the tube to be cooled by means of the heat sink. This heat sink can be a cold plate and/or a heat exchanger, for example. In this case, the contact surface is preferably enlarged by means of a (good) heat conductor.

In a further preferred embodiment, the heat sink or heat sinks is/are electrically insulated from the at least one electrode and preferably from both electrodes.

In a further preferred embodiment, the contact surface is or will be enlarged by means of a (good) heat conductor. In a preferred embodiment, the heat sink consists of an electrically insulating material or has such a material. In a further advantageous embodiment, the heat sink consists of a thermally conductive material or has such a material. In a further preferred embodiment, an electrical insulator is arranged between the electrode(s) and the heat sink.

In a further advantageous embodiment, at least one electrode and preferably both electrodes consist of an electrically and thermally conductive material or have such a material. In a further particularly preferred embodiment, the heat sink or heat sinks and/or the heat exchanger or heat exchangers of the electrodes are arranged outside the coating chamber and/or outside the vacuum chamber. In this way, on the one hand, the vacuum chamber can be kept small and, on the other hand, the heat generated can also be dissipated more easily. However, it would also be possible to arrange the heat sink(s) within the vacuum chamber and/or coating chamber.

In a further preferred embodiment, a (further) cooling body is provided for cooling the tube and/or the nozzle. This heat sink is preferably arranged within the vacuum chamber and/or the evacuated space. However, it would also be conceivable for this further heat sink to also be arranged inside the vacuum chamber.

In a further preferred embodiment, at least one electrode has at least one channel for conducting a cooling medium. Both electrodes preferably each have at least one channel for conducting a cooling medium. In this embodiment, the electrodes are cooled by the cooling medium. In a preferred embodiment, this at least one channel extends along the direction of extension of the electrode(s).

In a further preferred embodiment, the cooling medium is a cooling oil with food approval (H1) and/or the cooling medium has a conductivity of less than 10 μS/cm, preferably less than 5 μS/cm and particularly preferably less than 1 μS /cm and/or the coolant is formed or consists of ultrapure water.

The cooling medium is preferably a liquid cooling medium. The cooling medium is preferably selected from a group of cooling media which contains oil, water, (in particular liquid) nitrogen and carbon dioxide. In a further preferred embodiment, the cooling medium is electrically non-conductive.

In a further preferred embodiment, said channel has at least in sections a cross-section which is greater than 0.5 mm, preferably greater than 0.8 mm, preferably greater than 1.0 mm and particularly preferably greater than 1.2 mm and especially preferably greater than 1.4 mm.

In a further preferred embodiment, the channel has, at least in sections, a cross section which is less than 3 mm, preferably less than 2.5 mm, preferably less than 2.0 mm, preferably less than 1.8 mm and preferably less than 1. 6mm

In a further preferred embodiment, the channel has a substantially constant cross section. In a further preferred embodiment, the channel has a substantially circular cross-section. In a further preferred embodiment, the channel has a deflection, by means of which the direction of flow of the cooling medium is deflected.

The coating station preferably has connections for a flow and return for the cooling medium. These connections are preferably arranged outside the vacuum chamber. In a further preferred embodiment, several forward and reverse runs are provided for the two electrodes.

It would also be conceivable that a feed for the cooling medium is assigned to one electrode and the return to the other electrode, in which case the cooling medium is preferably transported or flows from one electrode to the other electrode.

In a further preferred embodiment, the coating station has a so-called heat pipe. A heat pipe is a heat exchanger that allows a high heat flow density using the heat of vaporization of a medium. In this way, large amounts of heat can be transported over a small cross-sectional area.

In a further preferred embodiment, the cooling device has an application device which applies a cooling medium to the at least one electrode. In this configuration, it is proposed in particular that the electrode be cooled by applying a cooling medium to it (in particular from the outside). This cooling can preferably take place between two coating processes. This cooling medium is preferably selected from a group of cooling media which contains liquid nitrogen or CO ₂ . Beside or in addition, it would also be conceivable for the cooling device to have a Peltier element.

In a further preferred embodiment, at least one electrode has a coiled and/or helical structure. This electrode preferably has a uniform helical structure with a pitch that is uniform at least in sections.

Both electrodes preferably have a coiled and/or helical structure. In this case, these two electrodes can jointly have a double-helix-like structure.

The two electrodes preferably extend at least in sections around the above-mentioned tube. In this case, however, the (double) helical structure of the electrodes preferably extends further in the direction of extension than the tube.

At least one electrode is preferably produced by a direct printing process.

In a further preferred embodiment, at least one electrode and preferably both electrodes are made up of at least two components. These two components are preferably made of different materials. Thus, one component can be designed as an (internal) core and the other component as a layer surrounding this internal component.

In a further advantageous embodiment, at least one electrode has a thickening at one end and in particular a lower end, in particular in order to supply at least one channel with cooling medium.

In a further advantageous embodiment, the device has an electrode receiving device for receiving at least one electrode. This electrode receiving device is preferably designed as an exchangeable and in particular quickly exchangeable and/or exchangeable unit without tools and/or coolant lines are designed as sealing couplings at least on one side and preferably on both sides.

In a preferred embodiment, the internal component of the electrode may be made of a material with good thermal conductivity, such as highly oriented pyrolytic graphite (HOPG). The material preferably has a thermal conductivity that is greater than 1300 W/K*m, preferably greater than 1500 W/K*m, preferably greater than 1700 W/K*m.

The external component can preferably consist of a material with good electrical conductivity properties, such as silver or high-temperature superconductors.

This configuration of the electrode is preferably an internally cooled electrode.

In a further preferred embodiment, the outer component or coating can consist of a material with very good thermal conductivity, for example HOPG (highly oriented pyrolytic graphite). The internal component can consist of a material with very good electrical conductivity properties, such as silver or high-temperature superconductors. The material used preferably also meets food technology requirements. The material used for the electrode is preferably food-grade. For example, the electrodes can be printed on stainless steel powder, aluminum or titanium.

In a further preferred embodiment, at least one electrode and preferably both electrodes have an easily cleanable surface. In this case, for example, a coating which uses the lotus effect can be provided.

In a further preferred embodiment, surface deactivation for coating deposits is provided.

In a preferred embodiment, at least one electrode is fabricated using additive manufacturing (e.g., metal 3D printing).

The present invention is also directed to an electrode arrangement for coating containers and in particular plastic containers, having a carrier on which a first electrode and a second electrode are arranged, these electrodes being spaced apart and both electrodes extending in a longitudinal direction of the electrode arrangement and wherein the electrode arrangement can be inserted into the container through a mouth of a container.

According to the invention, the electrodes can be cooled by means of a cooling device, the electrodes having at least one channel for conducting a cooling medium and/or the electrodes being curved at least in sections and/or the electrodes being made up of at least two components made of different materials.

The electrode arrangement preferably has a tube and/or a nozzle for conducting a flowable medium. This tube is preferably arranged at least in sections between the electrodes. This tube preferably consists of an electrically insulating material.

The present invention is also directed to a method for coating containers and in particular for coating the inner walls of plastic containers, the containers being fed to at least one - in particular stationary - coating station, the coating station having a first electrode and a second electrode and at least one electrode is introduced into the containers and wherein the coating station has a vacuum chamber inside which at least a part of the container to be coated and the first electrode are arranged and wherein a vacuum generating device (at least temporarily during the coating process) generates a vacuum in this vacuum chamber.

According to the invention, at least one electrode is cooled at least temporarily. In a preferred method, both electrodes are at least temporarily cooled. In addition to the electrodes, a tubular body is preferably also introduced into the containers, with the containers preferably being charged with a flowable medium through this tubular body. This tubular body is preferably also cooled at least temporarily.

In a preferred method, the cooling takes place by means of a heat sink and/or by means of a cooling liquid. In a further preferred method, the cooling takes place (also) during the coating process. In this method, the cooling preferably takes place while the electrode(s) are inside the container.

In a further embodiment, it can be advantageous to temporarily interrupt the cooling and/or even to remove the cooling medium from the electrode in sections. This can e.g. B. be accomplished by a switchable supply of compressed air or similar gases. It would thus be possible to adjust the temperature profile of the electrodes during the coating process or also in sections during several processes.

In a further preferred method, the cooling takes place between two coating processes. In this method, cooling preferably occurs while the electrode(s) are outside of the container. The containers are placed in a vacuum chamber for coating. Between the coating processes, i.e. when the coated container is transported out of the chamber and the new, uncoated container is introduced into the chamber, the electrodes are free and "without task". This period can be used for cooling. This cooling can be done either by injecting liquid nitrogen or liquid carbon dioxide. Spraying in water for cooling is also conceivable.

In a further preferred method, the electrode or the electrodes are cooled by being acted upon by a cooling medium, or the electrode(s) have a channel through which a cooling medium flows. This possibility for (particularly permanent) cooling of the electrodes lies in equipping them with cooling. This is preferably active cooling and particularly preferably active liquid cooling, ideally cooling with the aid of an electrically non-conductive cooling medium such as e.g. B. Oil or CO2 or N2 or similar.

• 1 Eine schematische Darstellung einer erfindungsgemäßen Vorrichtung in einer ersten Ausführungsform;
• 2 Eine erfindungsgemäße Vorrichtung in einer zweiten Ausführungsform;
• 3 Eine erfindungsgemäße Vorrichtung in einer dritten Ausführungsform;
• 4 Eine erfindungsgemäße Vorrichtung in einer vierten Ausführungsform;
• 5 Eine erfindungsgemäße Vorrichtung in einer fünften Ausführungsform;
• 6 Eine erfindungsgemäße Vorrichtung in einer sechsten Ausführungsform;
• 7a, 7b Zwei Darstellungen einer helixartigen Elektrodenanordnung mit Kühleinrichtung;
• 8a - 8c Drei Darstellungen zur Veranschaulichung einer Kühlung der Elektroden;
• 9a, 9b Zwei Darstellungen zur Veranschaulichung einer als Heatpipe ausgeführten Kühleinrichtung;
• 10a, 10b weitere Ausgestaltungen einer Elektrodeneinrichtung;
• 11a, 11b Zwei Darstellungen einer Kühleinrichtung;
• 12a, 12b Zwei Darstellungen einer Beschichtungsstation;
• 13 Eine Darstellung einer erfindungsgemäßen Anordnung.

Further advantages and embodiments result from the accompanying figures. Show in it:

• 1 A schematic representation of a device according to the invention in a first embodiment;
• 2 A device according to the invention in a second embodiment;
• 3 A device according to the invention in a third embodiment;
• 4 A device according to the invention in a fourth embodiment;
• 5 A device according to the invention in a fifth embodiment;
• 6 A device according to the invention in a sixth embodiment;
• 7a , 7b Two representations of a helical electrode arrangement with a cooling device;
• 8a - 8c Three representations to illustrate cooling of the electrodes;
• 9a , 9b Two representations to illustrate a cooling device designed as a heat pipe;
• 10a , 10b further configurations of an electrode device;
• 11a , 11b Two representations of a cooling device;
• 12a , 12b Two representations of a coating station;
• 13 A representation of an arrangement according to the invention.

1 shows a representation of a device according to the invention or a coating station for coating containers 10. The containers 10 are introduced into a vacuum chamber 12 and this is subjected to a vacuum or is evacuated. An evacuated space 14 can be located around the chamber.

The reference character P designates the plasma generated inside the container 10 . For this purpose, two electrodes 22, 24 are provided between which voltage is applied. One or more gas mixtures are introduced into the container via a tubular body or a nozzle 8 . In the embodiment shown here, three gas mixtures G1, G2 and G3 are supplied. For this purpose, three valve devices 42a, 42b and 42c are provided, which control the supply of the gas mixtures.

The reference number 40 denotes a vacuum generating device, with three pressure levels V1, V2 and V3 being provided here, with which the vacuum space can be charged or with which air can be withdrawn from the vacuum space.

At least two and advantageously three valves 44a, 44b, 44c are also provided for this purpose.

The reference number 6 designates in its entirety a cooling device here for cooling the electrodes 22 and 24. Two cooling bodies 62 are provided, which serve to cool sections of the electrodes. The electrodes themselves are made of a thermally conductive material so that the cooling effect can be passed on.

The reference number 64 designates a contact in order to connect a plasma generator 18 to the two electrodes. In the device shown here, the cooling takes place with a cooling medium, for which purpose a supply line V and a return line R are provided. At the in 1 In the embodiment shown, the two electrodes 22, 24 are cooled separately.

2 shows a further embodiment of a device according to the invention. In addition to the heat sinks 62 , heat conductors 66 are also provided here, which are each arranged between the electrodes or the electrode ends 22 and 24 and the actual heat sinks 62 . The contact area with the heat sinks can be increased by means of this heat conductor 66 .

At the in 3 In the embodiment shown, in addition to the heat sinks 62 for the electrodes, electrical insulators 68 are also provided, which are arranged between the heat conductors 66 and the heat sinks 62 here. In this way, the electrical insulation between the electrodes is improved.

At the in 4 In the embodiment shown, there is also a cooling device 70 for cooling the tube or the nozzle 8 . This cooling device 70 can be cooled by the same coolant flow that is also used to cool the electrodes. It can be seen that here the cooling device 70 for cooling the tube 8 or the nozzle is arranged inside the vacuum space 14 , while the heat sinks for cooling the electrodes are arranged outside the vacuum space 14 .

At the in 5 In the embodiment shown, in addition to the heat sinks 62 shown above for cooling the electrodes, there are also cooling devices 72 for cooling the nozzle or the pipe, as well as another heat sink 74, which also serves to cool the electrodes. In this way, cooling bodies are provided both outside and inside the evacuated space for cooling the electrodes. In this way, even more efficient cooling of the electrodes is achieved.

At the in 6 The embodiment shown are additionally the ones already shown in 3 shown electrical insulators present.

It is noted that in the 1 - 5 The embodiments shown can be combined with one another, ie the electrical insulators can be added or omitted in all configurations. The existing cooling circuits or heat sinks can also be adapted to the prevailing requirements.

the 7a and 7b show another embodiment of the electrodes. The two electrodes 22 and 24 each have a helix-like structure or a double-helix-like structure. A connecting body 26 made of an electrically insulating material is provided at the upper end of these electrodes. This connecting body also serves to establish a flow connection for the tempering medium from one electrode to the other electrode.

As in 7b 1, a channel is formed inside the connecting body 26, which establishes the flow connection between the electrodes. Numeral 34 denotes a sealing ring.

In this embodiment, each electrode has only one integrated cooling channel. Since each treatment station has two electrodes (ie two electrodes are required to coat a container), the coolant flow takes place through the first electrode and the coolant return through the second electrode. Since both electrodes are subjected to high voltage during operation, there must be no electrically conductive connection between them, otherwise a short circuit will occur. For this reason, the cooling medium is transferred from one electrode to the other by means of a connecting part. This should consist of an electrically non-conductive or very poorly conductive material.

the 8a - 8b show a further embodiment of the electrodes. Here, too, the electrodes have a double-helix-like structure. Unlike the one in the 7a , 7b However, in the embodiment shown in 8a - 8c In the embodiment shown, two channels 36, 38 are provided in each electrode, which are in fluid communication with one another at the end via a connecting channel.

The reference numeral 8 designates the pipe or the nozzle, which, however, does not reach the end of the electrode in the direction in which it extends. It is possible that the length of the nozzle and/or its configuration, such as the presence of lateral openings, varies in different embodiments.

Another possibility, the in 9a , 9b The cooling option shown is to use a so-called heat pipe, which makes it possible to transfer large amounts of energy without external drives such as pumps or the like. In our design, the thermal energy could be conducted from the electrodes into the base of the device, where the energy could be dissipated via a type of heat exchanger. This structure would make it possible to create separate circuits that would not have to be opened even when changing the electrode. The interface would have to be designed as a separable heat exchanger and have additional insulating properties.

10a shows a further embodiment of the electrode arrangement. In this embodiment, the two electrodes are arranged on a carrier or base 52 and are U-shaped. In this embodiment, too, a coolant can flow through each of the electrodes separately. Again, the tube 8 is provided between the two electrodes. At the in 10b In the embodiment shown, both electrodes 22, 24 are each U-shaped and are each arranged on the base 52. The tube (not shown) can also be arranged here between the electrodes.

the 11a and 11b show two further alternative configurations of an electrode cooling system. At the in 11a The embodiment shown is externally cooled for the electrode (only partially shown) and in the case of the 11b shown embodiment is an internal cooling.

In both configurations, the electrodes are made up of two components, namely an inner core 92, 96 and a coating 94, 98 running around this core 92, 96.

In the internally cooled design ( 11a) the internal component has very good thermal conductivity properties. The external component has very good electrical conductivity. In this configuration, the cooling device is preferably in contact with the internal component 92.

In the externally cooled design ( 11b) the external component has very good thermal conductivity properties. The internal component has very good electrical conductivity. In this configuration, the cooling device 62 is preferably in contact with the external component 98.

The areas of the electrodes shown here are preferably arranged outside the vacuum chamber.

the 12a , 12b show two representations of a coating station, where in 12a the container is shown and in 12b the coating station is empty. The reference number 82 designates a carrier on which the coating station (and also further coating stations) is arranged.

Reference number 80 designates a cooling device and reference number 65 designates a nozzle which applies a jet of coolant to the electrodes while the vacuum chamber is empty. However, several such nozzles could also be provided.

the 13a and 13b show representations of the electrode arrangement. In this case, the reference symbols 112a and 112b designate two connections for supplying and discharging a coolant. Starting from the connections 112a and 112b, channels (not shown) lead to two distribution chambers 126 and 132. The cooling medium can be collected in these and distributed to the two electrodes or removed from them.
The electrodes each have end sections 116a, 116b, which are arranged in the electrical connection devices 114a, 114b. The reference numerals 122, 124 denote fastening means for fixing the electrodes.

Reference numerals 126 and 128 designate coolant openings in order to feed the coolant to the electrodes and to remove it again. The coolant is supplied to the electrodes in the opening portions 132 and 133 .

The plasma feed 136 can be seen between the electrodes 134a, 134b.

13b shows a detailed representation of the electrodes. The coolant channels 142 and 144 inside the electrode can also be seen here. Reference numeral 146 designates holding means for holding the electrodes in a holder.

14 shows a representation of a system 50 for manufacturing containers. Here, reference numeral 52 refers to a heating device, such as an infrared oven, which heats plastic preforms. The plastic preforms heated in this way are guided to a shaping device 54 for shaping plastic preforms into plastic containers and shaped there. For example, this device 54 can be a stretch blow molding machine.

Reference numeral 56 designates a transport device which transports the shaped containers. The containers can also be sterilized in the area of this transport device. The device 1 according to the invention, which is used for coating the manufactured containers, is connected to this transport device. This has a revolving transport device 2 here, such as a revolving chain, which feeds the containers to the individual coating stations 20a to 20c. The actual coating of the containers takes place while the containers are at a standstill, that is to say that the coating device 1 is operated in cycle operation. The reference number 23 designates a transfer unit or a further transport device, which removes the containers from the transport device 2 and then conveys them to the individual coating stations 20a, 20b, 20c.

The reference number 4 denotes a vacuum generating device, which is used to supply the individual coating stations 20a to 20f with a vacuum. “Supply with a vacuum” is understood to mean that air is removed from the respective chambers and a vacuum is thus generated.

Following the coating, the containers are filled with a liquid and in particular with a drink by means of a filling device 60 .

The applicant reserves the right to claim all features disclosed in the application documents as essential to the invention, provided they are new compared to the prior art, either individually or in combination. It is also pointed out that the individual figures also describe features which can be advantageous in and of themselves. The person skilled in the art recognizes immediately that a specific feature described in a figure can also be advantageous without adopting further features from this figure. Furthermore, the person skilled in the art recognizes that advantages can also result from a combination of several features shown in individual figures or in different figures.

Claims (15)

Device (1) for coating containers (10) with at least one coating station (20a, 20b, 20c...) and at least one transport device (2), which this coating station (20a, 20b, 20c...) the containers to be coated (10), the coating station having a first electrode (22) and a second electrode (24), at least one of these electrodes being insertable into the containers (10), the coating station (20a, 20b, 20c...) having a vacuum chamber (12), within which at least part of the container to be coated and the electrodes (22, 24) are arranged, as well as a vacuum generating device (4) which generates the vacuum in this chamber, characterized in that the device (1) has a cooling device (6) for cooling the electrodes (22, 24) that can be inserted into the containers (10). Device (1) after claim 1 , characterized in that the coating station (20a, 20b, 20b) has a tube (8) which can be inserted into the containers (10) and by means of which a medium, in particular a gaseous medium, can be fed to the container. Device (1) according to the preceding claim, characterized in that the device has a cooling device for cooling the tube (8). Device (1) according to at least one of the preceding claims, characterized characterized in that the cooling device has a heat sink that cools the electrodes (22, 24). Device (1) according to the preceding claim, characterized in that the heat sink is electrically insulated from the at least one electrode (22, 24). Device (1) according to at least one of the preceding claims, characterized in that at least one electrode has a channel (62) for conducting a cooling medium. Device (1) according to at least one of the preceding claims, characterized in that the cooling medium is preferably a cooling oil with a food approval (H1) and/or that the cooling medium has a conductivity of less than 10 µS/cm, preferably less than 5 µS/cm and particularly preferably less than 1 μS/cm and/or is formed from ultrapure water. Device (1) according to the preceding claim, characterized in that the channel has at least in sections a cross-section which is greater than 0.5 mm, preferably greater than 0.8 mm, preferably greater than 1.0 mm and particularly preferably greater than 1.2 mm and particularly preferably greater than 1.4 mm and/or the channel at least in sections has a cross section which is less than 3 mm, preferably less than 2.5 mm, preferably less than 2.0 mm, preferably less than 1.8 mm and preferably less than 1.6 mm. Device (1) according to at least one of the preceding claims, characterized in that the cooling device has an application device which applies a cooling medium to the at least one electrode. Device (1) according to at least one of the preceding claims, characterized in that at least one electrode has a coiled structure and/or at least one electrode is made up of at least two components made of different materials. Device (1) according to at least one of the preceding claims, characterized in that at least one electrode has a thickening at one end and in particular at a lower end in order to supply at least one channel with cooling medium. Device (1) according to at least one of the preceding claims, characterized in that the device (1) has an electrode receiving device for receiving at least one electrode and this electrode receiving device is designed as an exchangeable and in particular quickly exchangeable unit and/or that coolant lines are at least on one side and preferably on both sides as sealing couplings are designed. Electrode arrangement for coating containers with a carrier on which a first electrode (22) and a second electrode (24) are arranged, these electrodes (22, 24) being spaced apart and both electrodes extending in a longitudinal direction of the electrode arrangement and the Electrode arrangement can be inserted through a mouth of a container into the container, characterized in that the electrodes can be cooled by means of a cooling device (6), the electrodes having at least one channel for conducting a cooling medium and/or the electrodes are curved at least in sections and/or the electrodes are made up of at least two components with different materials and/or the cooling medium is a liquid cooling medium. Process for coating containers, the containers being fed to at least one - in particular stationary - coating station (20a), the coating station having a first electrode (22) and a second electrode (24), at least one electrode being introduced into the containers (10). and wherein the coating station (20) has a vacuum chamber (8), within which at least part of the container to be coated and the first electrode (22) are arranged and wherein a vacuum generating device generates the vacuum in this vacuum chamber, characterized in that the at least an electrode is cooled at least temporarily. procedure after Claim 14 , characterized in that the electrode is cooled by being acted upon by a cooling medium and/or the electrode has a channel through which a cooling medium flows.

Images