Fixing device as well as apparatus and method for corona treatment of electrically insulating materials

Abstract

Fixing device (8) for a device (1) for corona treatment of electrically insulating materials, comprising a base section (12) extending over the width of a high-voltage electrode (3) with several electrode segments (2), a plurality of spring tongues (7), wherein each spring tongue is assigned to one of the electrode segments (2) of the high-voltage electrode, and wherein the spring tongues are arranged to securely hold the associated electrode segment (2) in a respective position, wherein the respective position comprises an operating position (5) and a rest position (6), wherein the spring tongues (7) are arranged to engage in a first fixing notch (9) for assuming the operating position (5) and in a second fixing notch (10) for assuming the rest position (6) on the respective electrode segment (2).

Description

Field of invention

[0001] The present invention relates to a fixing device, a apparatus, and a method for corona treatment of electrically insulating materials. The electrically insulating materials are, in particular, plastic films. The apparatus typically comprises a counter electrode over which the electrically insulating material to be treated is guided, and a high-voltage electrode with a plurality of electrode segments that are pivotably mounted about an axis between an operating position and a rest position. Background and General Description of the Invention

[0002] Various devices for corona treatment are known from the prior art. DE 20 2004 016 083 U1 discloses a device for the corona treatment of electrically insulating materials, in particular plastic films, with a counter electrode over which the plastic film to be treated is guided, and with a high-voltage electrode extending transversely to the direction of travel of the plastic film, which is formed by a plurality of electrode segments. The electrode segments are directed towards the counter electrode and can be pivoted out of the treatment area. The discharge edges of the electrode segments are divided into individual discharge tongues spaced apart in the direction of travel of the plastic film and projecting towards the plastic film, wherein the discharge tongues of adjacent electrode segments are offset from one another in the direction of travel of the plastic film such that they are gapped.

[0003] One disadvantage of this device is that an incorrect or inaccurate positioning of the electrode segments can cause an uneven result or a faulty functioning of the device.

[0004] Furthermore, DE 36 16 150 A1 discloses an electrode for corona pretreatment devices or the like, which consists of several movably mounted segments that can be individually positioned in groups. DE 39 23 101 A1 describes a device for the surface treatment of film-like materials with corona discharges. DE 20 2004 016 083 U1 discloses a device for the corona treatment of electrically insulating materials, in particular plastic films.

[0005] The object of the present invention is therefore to provide a device for corona treatment that ensures error-free operation with uniform treatment of the material to be treated.

[0006] The problem is solved by the subject matter of the independent patent claims. Dependent claims constitute further developments of the invention.

[0007] This description details a device for corona treatment of electrically insulating materials, in particular plastic films. The device comprises a counter electrode over which the material to be treated, such as a plastic film, is guided, and several electrode segments of a high-voltage electrode, which are pivotably mounted about an axis between an operating position and a rest position. The device further includes a fixing device designed to position the electrode segments in a defined operating position and a defined rest position.

[0008] In other words, a first number of electrode segments can be held in the operating position, ranging from 0 to a subset of the electrode segments up to all electrode segments of the high-voltage electrode. A second number of electrode segments, similarly ranging from 0 to a subset of the electrode segments up to all electrode segments, can be held in the rest position by the fixing device. It is understood that, generally, the sum of the first and second numbers equals the total number of electrode segments. Thus, if the first number includes all electrode segments, the second number is 0. If the first number includes 10 fewer segments than the total number of electrode segments, then the second number includes the 10 electrode segments held in the rest position.

[0009] Corona treatment is often used in the finishing industry or in the production of plastic films or foils. Air can be used as the process gas. Alternatively, another gas can be used, with the device being arranged in a chamber filled with this process gas. The gases produced during the plasma discharge, especially ozone, can be extracted, allowing fresh air to enter the gap between the counter electrode and the electrode segments. The counter electrode can be designed as a roller, over which a tightly fitting plastic film can be guided. A high voltage, for example 10 kV at 20–40 kHz, can be applied between the counter electrode and the electrode segments of the high-voltage electrode. The counter electrode can be connected to ground potential.In the gap between the electrode segments and the counter electrode with the plastic film, a potential difference generates a plasma discharge or corona discharge. This plasma discharge processes or activates the material being treated, such as the plastic film, thereby oxidizing the surface and achieving a desired surface property. For example, surface activation through oxidation can increase the surface tension of a plastic film, thus ensuring better adhesion for printing inks and adhesives.

[0010] However, it can be advantageous for certain areas of the electrically insulating material to remain unactivated. Therefore, when the electrically insulating material is passed over the counter electrode, sections – measured across the width of the material, i.e., perpendicular to its direction of travel – can be kept free from activation by the high-voltage or segment electrode. If the material is web-like, as in the case of a plastic film, the result is that after treatment, some entire web strips remain untreated while others are treated. If, for example, bags are to be manufactured from the plastic film, the film must not be activated by corona treatment in the area of ​​the sealing seams, as this would reduce the seam strength.This can be achieved by exempting certain strip-like areas in the direction of travel of the plastic film from corona treatment. This is done by pivoting only the electrode segments belonging to these strips from an operating position to a rest position, thereby deactivating them. The remaining electrode segments stay in the operating position, so that the remaining areas of the plastic film are activated or treated.

[0011] The pivoting of the electrode segments between a rest position and an operating position around the axis typically occurs for an entire roll of material at the beginning of the treatment, after which the entire roll is treated according to the electrode segment settings. This pivoting can also be achieved, for example, by a drive mechanism such as an electric motor.

[0012] The fixing device is designed to secure the individual electrode segments at the first defined position of the operating position and at the second defined position of the resting position relative to the device. An advantage of this fixing device is that it ensures the reliable positioning of the electrode segments between the operating and resting positions. This prevents positioning errors of the electrode segments, which can lead to inadequate corona treatment of the plastic film. It has been observed that during the treatment process, for example, of an entire roll or several rolls of material, individual electrode segments can be moved from their operating position, either by gravity or by accidental contact, potentially resulting in an inconsistent treatment outcome.This can also occur if the electrode segment(s) are only slightly misaligned from their operating position, resulting in treatment that is no longer as satisfactory or at least does not produce a uniform treatment result. Existing corona treatment devices either deliver unsatisfactory results in such cases or are cumbersome to use.

[0013] The electrode segments each have a first and a second locking notch. The locking device is arranged and designed to engage in the first locking notch when the respective electrode segment is in the operating position, and to engage in the second locking notch when the respective electrode segment is in the rest position.

[0014] Advantageously, the fixing device can provide a separate spring tongue or detent spring for each electrode segment, designed to provide the first notch for the operating position and the second notch for the rest position on the respective electrode segment. For example, the electrode segment can snap into the respective notch. The ratio between the number of spring tongues and the number of electrode segments can also be a non-1 ratio, for example, more spring tongues than electrode segments or more electrode segments than spring tongues. Depending on the application, it may be advantageous for one spring tongue to hold two or even more adjacent electrode segments. This design can therefore potentially be more cost-effective to manufacture overall.Conversely, it can be advantageous to have more than one spring tongue holding an electrode segment, for example, for redundancy reasons, as the electrode segment remains held even if one spring tongue fails. Therefore, varying the number of spring tongues relative to the number of electrode segments may affect process reliability and / or manufacturing costs.

[0015] The multiple detent springs—specifically, one detent spring per electrode segment—provide a locking mechanism that enables secure adjustment of the electrode segments between the operating and rest positions. The first and second notches can be arranged on a circular section of the respective electrode segment around the axis. In addition to these two notches, further shaped sections can be present in the vicinity of the notches to improve the positive locking effect with a corresponding raised section on the detent spring.

[0016] Advantageously, several detent springs for the respective electrode segments can be integrated into a single spring assembly. In other words, a spring assembly can be provided that advantageously extends over the entire length of the high-voltage electrode and, in particular, provides a separate spring tongue or detent spring for a majority or all of the electrode segments. The spring assembly with its individual detent springs enables secure and easy positioning and retention of the detent springs relative to the electrode segments. Furthermore, a continuous spring assembly offers the advantage that it eliminates the need to individually attach numerous spring tongues or detent springs; instead, the entire spring assembly can be screwed to the electrode housing with a comparatively small number of fasteners (e.g., screws).For this purpose, the spring comb can have a base section, which is, for example, block-shaped or hollow. The detent springs can then extend from the base section and, for example, have one end fixed to the base section and one free end.

[0017] This design, as a spring comb – in other words, with a base section and locking springs attached to it – also allows for significantly easier removal of the spring comb. Removal may be necessary regularly, for example, to clean components of the electrically insulating material (plastic film) that evaporate during corona treatment, or to insert a replacement bar or an alternative spring comb.

[0018] A replacement beam comprising segmented electrodes with a different structure compared to the previous beam may be required if a second material to be treated with corona treatment is to be treated after a first material has been treated. In other words, a change of material may also necessitate a change of electrodes, and such an electrode change is considerably simplified by the proposed spring comb design.

[0019] Advantageously, each of the detent springs can have a raised section that is designed to engage precisely in the first notch on the electrode segment for the operating position and in the second notch on the electrode segment for the rest position. This raised section, which aligns with the notches, ensures a secure, positive locking mechanism.

[0020] Advantageously, the spring force of the detent spring can be selected such that the respective electrode segment can be adjusted around the axis between the operating position and the rest position by means of a drive element, such as an electric motor. A stepper motor can also be used as the electric motor, which can rotate the respective electrode segment by a defined angle between the rest position and the operating position. In this design, the drive force applied to the detent spring must at least slightly exceed the spring force in order to release or enable the adjustment of the electrode segment.

[0021] Alternatively or cumulatively, a lifting lug can be arranged on each detent spring by means of which the detent spring can be lowered to prepare a rotation or pivoting of the respective electrode segment with little or no resistance.

[0022] Regardless of the activation of the locking spring, i.e. by means of a drive, a lifting lug or by manually gripping the electrode segment and pivoting the electrode segment while overcoming the inertial force of the locking mechanism, the fixing of the electrode segment(s) can be coupled to a control mechanism that can react, for example, to unevenness in the plastic film or fluctuations in the film thickness that may precede a fault in the system - for example, if the film gets caught or tears.If a deviation is detected, the electrode segment can then be moved to its rest position or at least released from the locking mechanism, allowing it to pivot automatically before the corresponding part of the film enters the corona treatment area – i.e., the gap between the electrode and counter electrode – and an uneven distribution of the electrical discharge or a system shutdown occurs. This also prevents the discharge from penetrating the film and potentially causing burn holes.

[0023] Advantageously, the electrode segments can be arranged directly next to each other, enabling a complete corona treatment by plasma discharge between the electrode segments and the counter electrode of the material to be treated, such as the plastic film. This allows the entire surface of the plastic film to be activated by corona treatment in the direction of travel, or individual strip-like areas of the plastic film to be excluded from corona treatment by switching off selected electrode segments.

[0024] Advantageously, the operating position relative to a plane of symmetry along the axis can have a first angle between 20° and 70° on a first side of the device, while the resting position relative to the plane of symmetry can have a second angle between 40° and 70° on a second side of the device. This allows, for example, the operating position to be located in the upper right quadrant and the resting position in the upper left quadrant. In conventional devices, the electrode segments are typically free-hanging in operating mode and therefore oriented in the direction of gravity, with the electrode segments being rotated away to switch off. In contrast to these conventional devices, the snap-in device allows the operating position to be located in the upper right quadrant and the resting position in the upper left quadrant.This freedom in the arrangement of the operating position can be advantageously space-saving when assigning the device to a spatially limited environment, thus expanding its range of applications. In other words, fixing the electrode segments in the operating position allows for a freer choice of orientation or alignment for corona treatment, whereby the electrode segments can also be oriented laterally upwards and yet still be prevented from swinging out of the operating position on their own.

[0025] Advantageously, the first angle of the operating position relative to a plane of symmetry along the axis of the device can be chosen to be symmetrical to the second angle of the rest position. This results in symmetrical adjustment of the electrode segments and thus a compact device design. At the same time, this standardization of the device type can reduce production costs.

[0026] Advantageously, the detent spring can be arranged essentially horizontally and consequently orthogonally relative to a plane of symmetry of the device, with the detent spring being attached to an upper side of the base section in the form of a strip running parallel to the axis. This results in a compact design of the device. The raised section on the detent spring can, for example, be arranged on a plane of symmetry of the device that passes through the pivot axis.

[0027] Advantageously, each electrode segment can be positioned near or adjacent to the counter electrode in the operating position, so that an applied high voltage generates a plasma discharge in a gap between the electrode segment and the counter electrode, thereby treating the material to be treated, such as the plastic film, within this gap. This enables uniform corona treatment of the material to be treated, such as the plastic film, in the operating position.

[0028] Advantageously, in the rest position, each electrode segment can be positioned at a defined distance relative to the counter electrode, so that the applied high voltage does not result in a plasma discharge at that electrode segment. By moving the electrode segments from the operating position to the rest position, the contact surfaces of the electrode segments are moved away from the counter electrode, thus interrupting the plasma discharge.

[0029] Advantageously, the counter electrode can be designed as a cylindrical roller. A contact surface of each electrode segment can then be further advantageously shaped as a section of a cylindrical surface, so that in the operating position, a uniform gap with the same distance between the respective electrode segment and the counter electrode is created at every position of the gap. This results in a gap of uniform width, enabling reliable and error-free corona treatment across the entire gap area. The gap therefore preferably has the shape of a cylindrical surface section.

[0030] Advantageously, each electrode segment can have discharge tongues and recesses on a contact surface. In the operating position, a plasma discharge or corona discharge is generated between the discharge tongues and the counter electrode by applying high voltage to treat or activate the material. The discharge tongues and recesses can be oriented perpendicular to the direction of travel of the roller or the plastic film. This ensures uniform corona treatment, as high-voltage peaks and voltage gradients along the slot between the electrode contact surfaces are avoided.

[0031] Advantageously, the discharge tongues and the depressions can be shaped like a comb, with the width of the discharge tongues and the width of the depressions being essentially the same. This essentially equal width of the discharge tongues and the depressions ensures a uniform high voltage between the contact surfaces of the electrodes and thus a uniform corona treatment.

[0032] This description also defines a fixing device for a high-voltage electrode or for a device for corona treatment of electrically insulating materials as previously described. The fixing device comprises a base section extending across the width of the high-voltage electrode and a plurality of spring tongues. Each spring tongue is assigned to one of the electrode segments of the high-voltage electrode. The spring tongues are configured to securely hold the assigned electrode segment in a respective position, which includes at least an operating position and a rest position. In other words, the fixing device holds each electrode segment either in the operating position or in the rest position, depending on which position is required for the respective electrode segment.

[0033] The spring tongues are designed to engage in a first locking notch for the operating position and a second locking notch for the rest position on the respective electrode segment. In other words, the electrode segments have locking notches complementary to the shape of the spring tongue, so that the electrode segment can engage in either the operating or rest position on the spring tongue.

[0034] For example, the fixing device, comprising the base section and the plurality of spring tongues, can be designed as a spring comb. The spring comb can further be characterized by the fact that the individual spring tongues are arranged adjacent to one another in a fixing plane and are jointly attached to the base section or formed integrally with the base section. In this arrangement, the base section is designed as a rigid component. Such an arrangement consisting of a rigid base section and flexible spring tongues is advantageous because, firstly, the individual spring tongues can be operated independently of one another, since the deflection or operation of one spring tongue does not, or only minimally, change the deflection of another, especially an adjacent, spring tongue.In other words, the fixing device is designed so that when an electrode segment is moved from one position to another – for example, from the operating position to the rest position or back – no other electrode segment is moved out of its respective position.

[0035] The spring tongues of the fixing device can be designed as detent springs. Detent springs have a detent mechanism, allowing a snap-fit ​​connection between the detent spring and the electrode segment to be established and / or maintained. For example, each detent spring has a raised section that is designed to engage precisely in the respective first notch for the operating position and in the respective second notch for the rest position.

[0036] The spring tongues can each further have a free end designed to yield when force is applied from the direction of the adjacent electrode segment, in order to release the fixation of the electrode segment. In other words, when a force is applied that causes the spring tongue to detach from the electrode segment, the fixation of the electrode segment to the spring tongue can be released.

[0037] Another aspect of the invention is a method for corona treatment using the device described above. The electrode segments can be pivoted around the axis from their rest position to their operating position. The locking device can engage in the defined position of the operating position, thereby arranging the electrode segments in a defined position relative to the counter electrode.

[0038] The invention will now be explained in more detail using exemplary embodiments and with reference to the figures. Similar or identical elements may have the same reference numerals, and the features of the different embodiments can be combined. Brief description of the characters

[0039] They show: Fig. Figure 1 shows a schematic representation of a device for corona treatment; Fig. Figure 2 shows a detailed representation of the device. Fig. 1. Detailed description of the invention

[0040] Fig. Figure 1 shows a schematic representation of a device 1 for corona treatment of electrically insulating materials, in particular plastic films, comprising a Fig. The device 1 comprises a counter electrode in the form of a roller and several electrode segments 2 of a high-voltage electrode 3. The electrode segments 2 are pivotably mounted about an axis 4 and can be adjusted between an operating position 5 and a rest position 6. Furthermore, the device 1 includes a fixing device 8 with a plurality of detent springs 7 designed as a spring comb 8, which may be manufactured in one piece. The fixing device 8 has a base section 12, which in this example comprises the connected end of the spring tongues 7 and a support block 14 on which the connected end of the spring tongues 7 rests. For example, the spring tongues and base section can be punched from a sheet of metal, thereby forming the spring tongues 7 and simultaneously forming the connected end 16 of the spring tongues 7.In this example, the connected end 16 forms the base section 12 with the support block 14, such that the majority of spring tongues 7 rest on the support block 14. The support block 14 stabilizes the connected end 16, preventing it from bending when the fixing device 8 is actuated, thus ensuring that actuating one electrode segment 2 does not affect the fixing of the adjacent electrode segments 2.

[0041] Furthermore, the formation of the base section 12 enables the fixing device 8 to be easily attached to the electrode housing 18 surrounding the high-voltage electrode 1. Therefore, only a few fastening means 13 may be sufficient to attach the entire fixing device 8 to the electrode housing 18, and it is not necessary to attach each individual spring tongue 7 there.

[0042] Each of the electrode segments 2 has a first notch 9 for the operating position 5 and a second notch 10 for the rest position 6, which engages in a corresponding elevation 11 on each of the detent springs 7.

[0043] Fig. Figure 2 shows a side view of the device 1. Fig. 1 with the cylindrical counter electrode 20 in the form of a roller, over which the plastic film is guided in a defined direction of travel 21. Only a section of the counter electrode 20 is shown, with which the respective electrode segment 2 forms a gap 22 in the operating position 5, within which a plasma discharge generated by high voltage and thus the corona treatment takes place. Due to perspective limitations, since all electrode segments 2 are aligned either in the operating position 5 or the rest position 6, only two electrode segments 2 arranged one in front of the other are shown; the other electrode segments 2 (cf. Fig.1) are hidden behind each of them.

[0044] The electrode segments 2 are adjusted about the axis 4 between the operating position 5 and the rest position 6, with the corresponding elevation 11 of the detent spring 7 engaging in the first notch 9 for the operating position 5 or in the second notch 10 for the rest position 6. The operating position 5 can be arranged, for example, at an angle of 45° on a first side relative to a plane of symmetry 23 of the device 1, and the rest position 6 can be arranged, for example, at an angle of 45° on an opposite second side relative to the plane of symmetry 23. A portion of the device's volume is defined by the pivot width of the electrode segments 2. This portion can advantageously be assigned to a corner of the device through which the plane of symmetry runs, thus saving space.

[0045] The detent spring 7 is attached to an upper side 24 of a support block 25, which runs parallel to the axis 4. Each of the electrode segments 2 has discharge tongues 27 and recesses 28 on a contact surface 26. In the operating position 5, plasma discharges are generated between the discharge tongues 27 and the counter electrode 20 by applying high voltage, thus treating or activating the plastic film arranged in the gap 22. The width of the discharge zones 27 and the width of the recesses 28 are essentially the same.

[0046] It is evident to those skilled in the art that the embodiments described above are to be understood as examples and that the invention is not limited to them, but can be varied in many ways without departing from the scope of the claims. Furthermore, it is evident that the features, regardless of whether they are disclosed in the description, the claims, or the figures, also individually define essential components of the invention, even if they are described together with other features. In all figures, the same reference numerals represent the same objects, so that descriptions of objects that may only be mentioned in one figure, or at least not with respect to all figures, can also be applied to those figures with respect to which the object is not explicitly described in the description. Reference symbol list 1 Device 2 electrode segments 3 High-voltage electrode 4-axis 5 operating position 6 Resting position 7 Spring tongue or detent spring 8 Fixing device or spring comb 9 first fixing notch 10 second fixing notch 11 corresponding elevation or locking tab 12 Basic section 13 Fixing device fasteners 14 Support block 15 Free End 16 connected ends 18 electrode housings 20 Counter electrode 21 Direction of travel 22 columns 23. Plane of symmetry 24 top side 26 contact area 27 discharge tongues 28 depressions

Claims

[1] Fixing device (8) for a device (1) for corona treatment of electrically insulating materials, comprising a base section (12) extending over the width of a high-voltage electrode (3) with several electrode segments (2), a plurality of spring tongues (7), wherein each spring tongue is assigned to one of the electrode segments (2) of the high-voltage electrode, and wherein the spring tongues are arranged to securely hold the associated electrode segment (2) in a respective position, wherein the respective position comprises an operating position (5) and a rest position (6), wherein the spring tongues (7) are arranged to engage in a first fixing notch (9) for assuming the operating position (5) and in a second fixing notch (10) for assuming the rest position (6) on the respective electrode segment (2). [2] Fixing device (8) according to one of the preceding claims, wherein the fixing device (8) is designed with the base section (12) and the plurality of spring tongues (7) as a spring comb. [3] Fixing device (8) according to one of the preceding claims, wherein the fixing device can be attached to the device (1) by means of easily detachable fastening means, so that the fixing device is designed to be removable in the event of an electrode change or for easier cleaning. [4] Fixing device (8) according to one of the preceding claims, wherein the spring tongues (7) are designed as detent springs, and wherein each of the detent springs (7) has a protrusion (11) which is suitable to engage precisely in the respective first notch (9) for the operating position (5) and in the respective second notch (10) for the rest position (6). [5] Fixing device (8) according to one of the preceding claims, the spring tongue (7) further comprising a free end (15) which is designed to yield when force is applied from the direction of the adjacent electrode segment (2) in order to release the fixation of the electrode segment. [6] Fixing device (8) according to one of the preceding claims, further comprising a drive means, in particular an electric motor, designed for adjusting one or more electrode segments (2), wherein a spring force of the detent spring (7) is selected such that the respective electrode segment (2) is adjustable about the axis (4) between the operating position (5) and the rest position (6) by means of the drive means. [7] Device (1) for corona treatment of electrically insulating materials, in particular plastic films, comprising a counter electrode (20) over which the material to be treated, such as a plastic film, is guided, and several electrode segments (2) of a high-voltage electrode which are pivotably mounted about an axis (4) between an operating position (5) and a rest position (6), and wherein the device (1) comprises a fixing device (8) according to one of the preceding claims. [8] Device (1) according to the preceding claim, wherein the fixing device (8) is detachably attached to the device so that the fixing device can be removed in the event of an electrode change or for easier cleaning. [9] Device (1) according to one of the preceding claims 7 or 8, wherein the electrode segments (2) are arranged directly next to each other, so that a complete corona treatment by a plasma discharge between the electrode segments (2) and the counter electrode (20) of the material to be treated, such as the plastic film, can be carried out. [10] Device (1) according to any one of the preceding claims 7 to 9, wherein the operating position (5) has a first angle between 20° and 70° on a first side of the device (1) relative to a plane of symmetry (23) along the axis (4), wherein the rest position (6) has a second angle between 20° and 70° on a second side of the device (1) relative to the plane of symmetry (23). [11] Device (1) according to the preceding claim, wherein the first angle of the operating position (5) relative to a plane of symmetry (23) along the axis (4) of the device (1) is selected symmetrically to the second angle of the rest position (6). [12] Device (1) according to any one of the preceding claims 7 to 11, wherein the detent spring (7) is arranged substantially horizontally and orthogonally relative to the plane of symmetry (23), wherein the detent spring (7) is attached to an upper side of the base section which runs parallel to the axis (4). [13] Device (1) according to any one of the preceding claims 7 to 12, wherein in the operating position (5) each of the electrode segments (2) is arranged in the vicinity of the counter electrode (20), so that by applying a high voltage a plasma discharge is generated in a gap (22) between the electrode segment (2) and the counter electrode (20) and thereby the material to be treated, such as the plastic film, is treated in this gap (22). [14] Device (1) according to any one of the preceding claims 7 to 13, wherein in the rest position (6) each of the electrode segments (2) is arranged at a defined distance relative to the counter electrode (20) so that the applied high voltage does not lead to any plasma discharge. [15] Device (1) according to any one of the preceding claims 7 to 14, wherein the counter electrode (20) is designed as a cylindrical roller, wherein a contact surface (26) of each of the electrode segments (2) is formed as a section of a cylindrical surface, such that in the operating position (5) between the respective contact surface (26) and the counter electrode (20) a uniform gap (22) with the same distance between the respective electrode segment (2) and the counter electrode (20) is generated at each position of the gap (22). [16] Device (1) according to any one of the preceding claims 7 to 15, wherein each of the electrode segments (2) has discharge tongues (27) and recesses (28) on a contact surface (26), wherein in the operating position (5) a plasma discharge is generated between the discharge tongues (27) and the counter electrode (20) by applying high voltage in order to treat or activate the material. [17] Device (1) according to the preceding claim, wherein the discharge tongues (27) and the recesses (28) are shaped in the form of a comb, wherein the width of the discharge tongues (27) and the width of the recesses (28) are substantially the same. [18] Method for corona treatment using the device (1) according to any one of claims 7 to 17 above, wherein a plurality of electrode segments (2) are provided for treating an electrically insulating material, comprising the steps starting from a rest position (6) pivoting a first number of electrode segments about an axis (4) into an operating position (5), and Fixing the first number of pivoted electrode segments in the operating position (5) by means of a fixing device (7) and thereby securing the first number of electrode segments (2) in a fixed position relative to the counter electrode (20). Treating the electrically insulating material with the first number of electrode segments fixed by means of the fixing device.

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