The invention generally relates to a device for cleaning an anilox roll.

In flexography printing, a substrate is typically pulled through a series of print units, each of which comprises several rolls, such as an ink roll, meter roll, plate cylinder and impression cylinder. Anilox rolls are a type of meter roll that are used to transfer ink onto a substrate. An anilox roll is a hard cylinder whose surface is engraved with a fine raster of small dimples, also known as cells. The cells can be filled with ink to obtain a substantially even distribution of ink on the anilox roll surface. At a print unit, the substrate is pulled through an anilox roll and a plate cylinder wherein the plate cylinder comprises a flexible offset image, known as the plate. An impression cylinder may apply a pressure to the plate cylinder such that the image is transferred from the plate to the substrate. Every printing station typically prints a single colour which are overlaid to create a multicolour image.

Over time, the cells of the anilox roll become fouled of dried ink and other unwanted substances, which limits the capacity of the cells to carry ink thereby reducing the effectiveness of the roll. Therefor, anilox rolls need to be cleaned periodically.

Conventional cleaning devices require the disassembly of the anilox roll from the print unit to clean the anilox roll separately from the rest of the print unit. This can be quite cumbersome and time-consuming.

Alternatively, solutions for inline cleaning of the anilox roll, i.e. cleaning the anilox roll without complete disassembly from the print unit are developed. A known inline cleaning device therefore employs a cleaning head connected to a frame with cleaning medium supply means, the cleaning head having approximately the same length as the anilox roll and which cleaning head can be positioned with a washing side thereof against an outer surface of the anilox roll. In the washing side of the cleaning head, facing the outer surface of the anilox roll, a cleaning medium outlet opening is provided for supplying a cleaning medium received from the cleaning medium supply means to the anilox roll. The inline anilox roll may be rotated around its central axis during a cleaning process so that approximately the entire outer surface of the anilox roll passes by the washing side of the cleaning head for receiving the supplied cleaning medium.

Although the known device for inline cleaning allows for an adequate cleaning of the anilox roll, some further improvements may be desired.

Particularly, as the cleaning head of the known device is rather bulky, it may prove difficult in certain instances to manoeuvre the cleaning head in a suitable position against the outer surface of the anilox roll. For instance, while mounted in the printing unit, only part of the anilox roll may be exposed for cleaning. The print unit and/or the near surroundings of the print unit wherein the anilox roll is provided may pose obstructions for the known inline cleaning device from reaching the outer surface of the anilox rolls, therefore rendering it difficult or even impossible to use the device in such instances.

An aim of the present invention is therefore to provide an inline cleaning device and method for cleaning of an anilox roll having one or more desired improvements. It is preferred to provide an inline cleaning device that can be employed in many or all cases and circumstances for inline cleaning of an anilox roll. It is also preferred to provide an inline cleaning device with improved cleaning capabihties, and which preferably operates substantially autonomous. In a first aspect the invention provides a cleaning device for inline cleaning of an anilox roll comprising a cleaning medium supply means having a cleaning medium container and a supply pump for pumping a cleaning medium from the container to a cleaning medium outlet opening of the device; and a cleaning head which at a washing side comprises the outlet opening for providing the cleaning medium onto the anilox roll, and an extraction opening which is arranged to extract cleaning medium from the anilox roll, wherein the cleaning head is movably coupled with the supply means and arranged to be moved along an outer surface of the anilox roll at least in a longitudinal direction of the anilox roll in use of the device during inline cleaning of the anilox roll.

As the cleaning head can move along the outer surface of the anilox roll for a complete cleaning thereof, the cleaning head can have a relatively compact size such that it can reach the anilox roll more easily while the anilox roll is inline, i.e. wile installed in the print unit. The supply means can supply a cleaning medium, for example conducted through a supply channel, to the cleaning head. The cleaning medium can be supplied to the anilox roll through an outlet opening at the washing side of the cleaning head. By rotation of the anilox roll along its central axis, it is possible to treat the surface of the anilox circumferentially around the anilox. The cleaning head is arranged to be moved longitudinally along the outer surface of the anilox roll. Due to rotation of the anilox roll and longitudinal movement of the cleaning head, essentially the whole outer surface of the anilox roll is affected by the cleaning head. Consequently, at essentially the whole outer surface of the anilox roll an amount of cleaning medium is deposited such that essentially all cells on the outer surface of the anilox roll can be cleaned, without the need for disassembly and separation of the anilox roll from the print unit. It is preferred that during a cleaning process the cleaning medium is continuously extracted from the anilox roll after deposition of the cleaning medium onto the outer surface of the anilox roll, such that a possible leakage or spillage of cleaning medium with extracted ink remnants and other foul is minimized and the cells on the anilox roll are cleared from cleaning medium. Such extraction of the cleaning medium is particularly desirable in inline cleaning to prevent intrusion of cleaning medium further into the print unit which may damage and/or contaminate components of the print unit. Cleaning medium can be extracted from the anilox roll through the at least one extraction opening at the washing side of the cleaning head. The cleaning device may be provided with an extraction pump for extracting the cleaning medium from the anilox roll through the at least one extraction opening. The extracted cleaning medium may for example be conducted by means of a extraction channel from the extraction opening away from the cleaning head. The extraction pump may also be integral with the supply means or share a housing with the supply pump.

Importantly the compact cleaning head of the present invention provides the opportunity of cleaning the anilox roll in cramped spaces, as are typically found on printing sites where multiple print units are closely spaced from one another.

In an embodiment, the washing side of the cleaning head has a central part and a peripheral part; the central part comprising the at least one outlet opening and the peripheral part comprising the at least one extraction opening. In use of the device, during cleaning of the anilox roll, rotation of the anilox roll around its central axis moves part of the outer surface of the anilox roll across the washing side of the cleaning head. Cleaning medium is deposited, through at least one outlet opening provided in the central part of the washing side, onto that part of the outer surface that is covered by the washing side. To avoid intrusion of cleaning medium into the print unit it is preferred that the deposited cleaning medium is extracted from the part of the anilox roll when it moves past the washing side. By providing the at least one extraction opening peripheral to the at least one outlet opening, the cleaning medium can be extracted before the anilox roll rotates further and in either direction of rotation of the anilox roll. Moreover, it allows the cleaning head to be moved along the outer surface of the anilox roll in any direction, while ensuring adequate extraction of the cleaning medium with minimized leaking and spillage.

Optionally, the cleaning device comprises a plurality of outlet openings distributed over the washing side of the cleaning head. A plurality of outlet openings may for example be distributed over a central part of the washing side of the cleaning head. This allows evenly distributed deposition of cleaning medium at the washing side onto the anilox roll. It furthermore allows spraying, for instance under pressure, of cleaning medium onto a plurality of positions of the anilox roll for efficient cleaning.

Optionally, the cleaning device comprises a plurality of extraction openings distributed over the washing side of the cleaning head. A plurality of extraction openings may for example be distributed over the peripheral part of the washing side of the cleaning head. It is preferred that essentially all deposited cleaning medium is extracted from the anilox roll to prevent contamination of the print unit. As such, it is preferred that a plurality of extraction openings are finely distributed at a peripheral part of the washing side of the cleaning head such that a central part of the washing side, where at least one outlet opening may be provided, is substantially surrounded. It is envisioned that a single extraction opening can be provided in the peripheral part of the washing side, wherein the extraction opening surrounds the central part. In an embodiment, at the central part of the washing side of the cleaning head a further opening is provided, being one of an outlet opening and an extraction opening. The further opening can for example be a further outlet opening for supplying water to the anilox roll to rinse the anilox roll, removing cleaning medium from the cells of the anilox roll. The further opening may also supply a further cleaning medium or an additive.

Alternatively, the further opening can for example be a further extraction opening for extracting cleaning medium from the anilox roll. In an embodiment, in the central part of the washing side of the cleaning- head, a plurality of the outlet openings are arranged in a first array extending in one dimension, and a plurality of the further openings are arranged in a second array parallel to first array, wherein, in use of the cleaning device during inline cleaning, the first and second array extend in a direction parallel to the central axis of the anilox roll. During inline cleaning, the anilox roll can be rotated around its central axis such that cleaning medium can be deposited circumferentially around the anilox roll by the cleaning device. As such, part of the outer surface of the anilox roll is moved through the area covered by the washing side, due to the rotation of the anilox roll. In the direction of rotation, a cell on the outer surface of the anilox encounters a first one of the first array and the second array, and subsequently a second one of the first array and the second array. For example, a cell on the outer surface of the rotating anilox roll may be moved through the area covered by the cleaning head, wherein the cell is first covered by a peripheral part of the washing side comprising at least one extraction opening. Through the extraction opening loose particles may be extracted from the cell. Subsequently, the cell will be covered by the central part of the cleaning head, first encountering the first array of outlet openings. The first array of outlet openings can deposit an amount of cleaning medium onto the anilox roll, preferably into the cell. Due to ί rotation of the anilox roll the cell will subsequently encounter the second array of further openings. The second array may for example comprise outlet openings for supplying water to the anilox roll to rinse the anilox roll. Alternatively, the second array of further openings may comprise extraction openings, arranged to extract at least part of the supplied cleaning medium by the first array. Lastly, the cell will be covered by an opposite peripheral part of the washing side, comprising an extraction opening through which cleaning medium, ink remnants and other foul can be extracted from the cell on the anilox roll outer surface. The cell will ideally be cleared from ink remnants and other foul, before it exits the covered area of the washing side, to prevent contamination of the print unit.

It is envisioned that the anilox roll can be cleaned in a three-step process using the cleaning device, wherein, in a first step, substantially the whole outer surface of the anilox roll is pre-cleaned with water. Said water is preferably applied to the outer surface of the anilox roll under pressure, for example at approximately 90-100 bar, to remove loose ink remnants from the cells of the anilox. Said water is also preferably heated, for example up to approximately 50°C, to warm up the anilox roll for effectively cleaning the anilox roll in a second step in the three-step cleaning process. In the second step of the cleaning process, substantially the whole outer surface of the anilox roll is provided with a cleaning medium. The cleaning medium can for example serve as a solvent for dissolving ink remnants in the cells, wherein the effect of the cleaning medium on the ink remnants is amplified when the anilox roll is warmed up in the first step of the cleaning process.

In a third step of the cleaning process, the whole anilox roll is rinsed with water, wherein the water is preferably applied to the anilox roll under pressure. The cleaning medium in the first step can for example be provided through the first array of outlet openings, and the water in the second step can be provided through the second array of further openings. During every step of the three step cleaning process, the applied cleaning medium and/or water is extracted from the anilox roll through the at least one extraction opening.

In an embodiment, the cleaning head at the washing side comprises a concave outer surface, adopted to match the convex curvature of the outer surface of the anilox roll. It is preferred that the shape of the washing side is configured to closely match the shape of the anilox roll, in order to minimise the distance between the outer surface of the anilox roll and the washing side of the cleaning head. It is, for example, preferred that the distance between a periphery of the washing side and the outer surface of the anilox roll is minimised. If the at least one extraction opening is provided in a peripheral part at the washing side of the cleaning head, it desirable to minimise the gap between said at least one extraction opening and the anilox roll to adequately extract cleaning medium, ink remnants and other foul from the cells of the anilox roll. It is also preferred that the at least one outlet opening can be brought close to the outer surface of the anilox roll to accurately spray cleaning medium, for example by force, into the cells of the anilox roll, for optimal deep cleaning of the cells.

Optionally, the device can be provided with sealing means at the washing side, configured at least partly around a perimeter of the washing side of the cleaning head arranged to sealingly engage with the anilox roll in order to prevent leakage of cleaning medium from a space defined between the washing side of the cleaning head and the anilox roll. The concave washing side of the cleaning head being matched to the convex curvature of the anilox roll, can be brought close to the surface of the anilox roll such that no additional sealing means is required. In an embodiment, the cleaning head comprises a main piece forming an inlet side of the cleaning head and a mouthpiece comprising the concave outer surface, wherein the mouthpiece and main piece are detachably coupled to one another. The concave shape of the mouthpiece may for example be adapted to the specific dimensions of a certain anilox roll. As such, the mouthpiece can be interchanged with another mouthpiece, having a different concave shaped outer surface adapted to another, differently dimensioned, anilox roll. The mouthpiece may for example be coupled to the main piece by means of a snap connection, which provides a secure coupling and convenient detachment to enable efficient replicability with another mouthpiece.

In an embodiment the cleaning device further comprises a guiding means arranged to guide the cleaning head along an outer surface of the anilox roll at least in a longitudinal direction of the anilox roll. A guiding means can provide guidance of the cleaning head to affect substantially the whole outer surface of the anilox roll. During inline cleaning of the anilox roll, the roll may be rotated around its central axis, such that the guiding means are arranged to guide the cleaning head along the outer surface of the anilox roll in a longitudinal direction parallel to the central axis of the anilox roll. The guiding means may for example guide the cleaning head along a substantial linear path parallel to the central axis of the anilox roll.

Optionally, the guiding means may also guide the cleaning head in a circumferential direction, transverse to the central axis of the anilox roll, around the anilox roll.

Optionally, the guiding means comprise a guiding rail extending parallel to a central axis of the anilox roll substantially along the whole length of the anilox roll, wherein the guiding rail is arranged to guide the cleaning head along an outer surface in a longitudinal direction parallel to the central axis of the anilox roll. This allow the cleaning head to be moved from a first end of the anilox roll to a second end such that, when the anilox roll is rotated around its central axis during inline cleaning, essentially the whole outer surface of the anilox roll is affected by the cleaning head. It is preferred that the rotational speed of the anilox roll and the translational velocity of the cleaning head are mutually arranged such that the washing side of the cleaning head affects substantially the whole outer surface of the anilox roll.

Optionally, the cleaning device further comprises support means for supporting the guiding means on a support surface and for fixating the guiding means relative to the anilox roll. This allows accurate positioning of the cleaning head relative to the anilox roll during inline cleaning. In use of the device, during inline cleaning, cleaning medium is supplied to the anilox roll. It may be preferred that the cleaning medium is sprayed onto the anilox roll under pressure for more effective cleaning of the anilox roll. The support means can fixate the guiding means to the anilox roll such that the distance between the outer surface of the anilox roll and the washing side of the cleaning head remains substantially the same, despite a force exerted on the cleaning head, for example as a result of the spray force. The support means may be detachably coupled to a suitable surface in the near

environment of the anilox roll, for example to the floor and/or the frame of the print unit. Detachable coupling to the environment can for example be estabhshed by means of magnetisable connection elements. The support means may also be coupled to the anilox roll, for example to the axle of the anilox roll to fixate the guiding means relative to the anilox roll.

In an embodiment, the support means are adjustable, preferably telescopic, to enable a fixation thereof between the support surface and the guiding means. This allows adaptation to the environment of a specific anilox roll. For example, after inline cleaning of a first anilox roll, the cleaning device can be brought to a second anilox roll at another print unit, wherein the support means can be adjusted to the environment of the second anilox roll. As such, the guiding means can be adequately supported in various environments, such that the cleaning head can access an anilox roll for inline cleaning in all such environments.

In an embodiment, the pump is arranged to supply a hquid cleaning medium under pressure to the anilox roll. The cleaning medium can be a water based cleaning medium, for example comprising a detergent diluted with water, or based on another solvent. The liquid cleaning medium can be contained in a container and pumped to the cleaning head through a conducting channel. The conducting channel can for example be a flexible conduit which brings the container containing the cleaning medium in fluid connected with the at least one outlet opening of the cleaning head.

Flexibility of the conduit is preferred to allow the cleaning head to move along the outer surface of the anilox roll while the container containing the cleaning medium can be kept stationary. The container containing the cleaning medium may for example be provided on a carriage for convenient manoeuvrability. It is envisioned that the supply pump may also be provided on the carriage.

In an embodiment, the cleaning device comprises a sensor for measuring and providing data of the position of the cleaning head relative to the anilox roll. The sensor data can for example be used to at least partly automate the cleaning process. Furthermore, it is preferred to accurately control the distance between the cleaning head and the anilox roll for optimal

extraction of cleaning medium form the anilox roll to prevent leakage and contamination. Also the position of the cleaning head in a longitudinal direction of the anilox roll can be determined with a sensor to control the translational speed of the cleaning head along the outer surface in the longitudinal direction. The translational speed is preferably adapted to the rotational speed of the anilox roll.

In an embodiment, the sensor is provided in the cleaning head. This allows accurate measurement of the position of the cleaning head relative to the anilox roll. The cleaning head can for example be provided with an optical sensor arranged to measure the distance between the washing side of the cleaning head and the outer surface of the anilox roll. The cleaning device may further be provided with sensors for measuring parameters of the cleaning medium, for example for measuring flow and/or pressure, and/or concentration. A sensor may also be provided for measuring properties of the anilox roll, such as a degree of fouling of the cells and/or the

effectiveness of the cleaning. It may also be preferred to obtain a measure for the cleaning medium remaining in the cells outside of the area covered by the washing side of the cleaning head, for example by means of a moisture sensor measuring the moist content residing in the cells. In an embodiment, the device comprises processing means for processing data obtained from the sensor to enable automation of the movement of the cleaning head. The cleaning process may be automated such that, after installation of the device, the positioning of the cleaning head is controlled by the processing means. The processing means can control the position of the cleaning head based on the data generated by a sensor. For example, during cleaning of the anilox roll, while the anilox roll rotates around its central axis, it may be possible to hold the cleaning head in a position until a satisfactory degree of cleanness is obtained. Also, the extraction pump may be controlled by the processing means to increase extraction rate, based on sensor data regarding moist content in the cells. The cleaning head may also be controlled by the processing means to track a certain trajectory along the outer surface of the anilox roll, in order to affect essentially the whole outer surface of the anilox roll. The trajectory may for example be optimised to clean the anilox roll energy efficient, and/or using minimal amounts of cleaning medium and/or water.

The described embodiments illustrate that the cleaning device according to the invention is particularly suited for cleaning an anilox roll. However it will readily be appreciated and understood by a person skilled in the art that a cleaning device according to the invention, and particularly in accordance with the described embodiments, is also suitable for cleaning other products and/or surfaces.

Thus, the invention in a further aspect provides a cleaning device suitable for cleaning any surface, comprising a cleaning medium supply means having a cleaning medium container and a supply pump for pumping a cleaning medium from the container to a cleaning medium outlet opening of the device; and a cleaning head which at a washing side comprises the outlet opening for providing the cleaning medium onto a surface to be cleaned, and an extraction opening which is arranged to extract cleaning medium from the surface, wherein the cleaning head is movably coupled with the supply means and arranged to be moved along the surface at least in use of the device during cleaning of the surface. Such cleaning device may be used to clean any surface. For example the cleaning device can be used to effectively clean surfaces of all sorts of structures, buildings, vehicles and other types of devices and products.

Importantly, in view of the provision of the cleaning medium outlet opening and the extraction opening in the washing side of the cleaning head it is possible to simultaneously supply cleaning medium to a surface to be cleaned and extract cleaning medium from said surface, so that excessive spill of cleaning medium and/or water is prevented with the cleaning device according to the invention irrespective of the actual surface to be cleaned with the cleaning device.

To minimize a possible spill of cleaning medium and/or water it is preferred that the surface of the cleaning head at the washing side is adaptable to the surface to be cleaned, e.g. the shape of the cleaning head at the washing side is configurable to closely match the shape of the surface to be cleaned such that the surface of the cleaning head at the washing side is, in use, approximately parallel to the surface to be cleaned. As such a distance between the surfaces can be optimised, i.e. kept to a minimum while allowing the cleaning head to be moved along the surface, to allow for a reliable extraction of most of the cleaning medium and/or water to minimize undesired spillage.

For example the washing side of the cleaning head may be formed of, or comprise, a deformable layer, preferably an elastically deformable layer, which may be configured as desired for a particular cleaning. In addition, or alternatively, the cleaning device may comprise a cleaning head with a main piece forming an inlet side of the cleaning head and a mouthpiece

comprising the outer surface at the washing side, wherein the mouthpiece and main piece are detachably coupled to one another. The shape of the mouthpiece may for example be adapted to the specific dimensions of a certain surface to be cleaned. The mouthpiece can be interchanged with another mouthpiece, having a differently shaped outer surface adapted to another, differently dimensioned, surface.

It will be appreciated and understood that the cleaning device may comprise a relatively compact cleaning head. The cleaning head may for example be configured as a portable, particularly handheld, cleaning head. Preferably the whole cleaning device is configured as a portable device, which more preferably is adapted to be handheld in use during cleaning.

For securing and maintaining an optimal distance between the washing side and the surface to be cleaned in use of the cleaning device, guiding means are preferably provided in the cleaning device which are arranged to guide the cleaning head along the surface to be cleaned. The cleaning device further preferably comprises support means for supporting the guiding means on a support surface and for fixating the guiding means relative to the surface to be cleaned. In use of the device, during cleaning, it may be preferred that the cleaning medium is sprayed onto the surface under pressure, e.g. the cleaning device is a high-pressure cleaner, for more effective cleaning of the surface to be cleaned. The support means can fixate the guiding means to the surface to be cleaned such that the distance between the surface and the washing side of the cleaning head remains substantially the same, despite a force exerted on the cleaning head, for example as a result of the spray force. The support means may be

detachably coupled to a suitable surface in the near environment of the surface to be cleaned. Detachable coupling to the environment can for example be established by means of magnetisable connection elements.

To avoid unnecessary spillage of cleaning medium and/or water it is preferred that the deposited cleaning medium and/or water is extracted from the surface when the cleaning head moves. Accordingly, it is preferred that the extraction opening is provided peripheral to the outlet opening at the washing side, so that practically all cleaning medium and/or water can be extracted before the cleaning head is moved, i.e. relocated, with respect to the surface to be cleaned. As has been described in the foregoing the cleaning device according to the invention is configured to supply a cleaning medium to a surface to be cleaned, in particular a surface of an anilox roll. However, it will be understood that such cleaning medium to be supplied by the device is not hmited to fluids or compositions comprising a particular cleaning agent, e.g. chemical cleaning compound, but may instead also consist of water, e.g. tap water, as water for some cleaning purposes may form an adequate means to clean the surface, particularly, but not necessarily, if supplied under relatively high pressure. Thus, the cleaning device according to a particular embodiment of the present invention may be configured as a water cleaner, particularly a high-pressure water cleaner, wherein the cleaning medium container contains an amount of water as cleaning medium and wherein the supply pump optionally is configured to supply the water as cleaning medium under high pressure.

In another aspect, a cleaning head as used in a device according to the foregoing is provided.

Description of the figures. The various aspects of the invention and embodiments thereof will now be discussed in conjunction with drawings. In the drawings:

Fig. 1 shows the cleaning device positioned at a print unit;

Fig. 2A shows the cleaning head, wherein a plurality of outlet openings are highlighted;

Fig. 2B shows the cleaning head, wherein a plurality of extraction openings are highlighted;

Fig. 2C shows the cleaning head, wherein a plurality of further openings are highlighted;

Fig. 2D shows the cleaning head having a main piece and a mouthpiece; Fig. 3 shows a view of the washing side of the cleaning head.

Fig. 1 shows a perspective view of the cleaning device 1 positioned at a print unit 2. A cleaning head 3 is positioned near an anilox roll 4 which is mounted in the pint unit 2. The cleaning head can be guided along the outer surface of the anilox roll by a guiding means 5. In Fig. 1, the guiding means comprises a guiding rail 6. The guiding rail 6 comprises two parallel rail members 7,8 extending parallel to one another and parallel to the central axis of the anilox roll 2. The length of the rail members 7,8 is essentially the same as the length of the anilox roll, such that the cleaning head 3 can be guided along the whole length of the anilox roll 2.

For creating a stiff construction, the rail members 7,8 are connected by rods 9.

The cleaning head 3 can be mounted to a cleaning head carrier 14 which is supported and guided by the guiding rail members 7,8. The cleaning head carrier 14 may be moved along the length of the guiding rail 5 by means of wheels 10, 11, 12,13. The wheels 10, 11, 12, 13 may for example be drivable to move the cleaning head carrier 14 along the guiding rail 5. It is also envisioned that the carrier is driven by drive means, for example an electromotor. The drive means may for example be provided on the cleaning- head carrier 14 or on the guiding means. The drive means can drive the cleaning head carrier 14 through a transmission such as a drive belt for example.

The wheels 10, 11, 12, 13 also secure the cleaning head 3 and/or the cleaning head carrier 14 to the guiding rail 5. Two wheels 10,11 are arranged on opposite side of the guiding rail 5, from the other two wheels 12, 13. This provides fixation of the cleaning head carrier 14 to the guiding rail members 7,8. The guiding rail members 7.8 may be provided with additional fixation members to constrain the cleaning head carrier in other directions than the guiding direction along the length of the guiding rail 5. Each guiding rail member 7,8 can comprise an indentation along the length of the guiding rail member 7,8 forming a track for the wheels 10, 11, 12, 13. This track can also constrain the movement of the cleaning head carrier 14, such that the cleaning head carrier 14 can only be moved along the length of the guiding rail 6.

The cleaning device further comprises two spacers 20,21, provided near either end of the anilox roll 4. The spacers 20,21 define a desired distance between the guiding means 5 and the anilox roll 4, such that the cleaning head 3 is optimally spaced from the outer surface of the anilox roll 4. The spaces 20,21 can optionally be coupled to the guiding means 5 and may be coupled to the anilox roll 4, for example to the axle of the anilox roll 4. The spacers may be removed when the cleaning device 1 has been positioned, before the cleaning process.

The cleaning device further comprises support means 15 for supporting the guiding means 6 on a support surface 16. The support surface 16 can for example be the ground upon which the print unit is supported. The support means 15 comprises two posts 19,20 supporting at least part of the weight of the cleaning device 1. In addition, the support means 15 can be adjustable to adapt to the environment of the anilox roll 4 to be cleaned. In Fig. 1 the support means 15 comprise telescopic beams 17 which are substantially rigid while being adjustable lengthwise. This allows the support means 15 to support and fixate the guiding means 6 relative to the anilox roll 4, while being adaptable to the specific environment of the anilox roll 4, which is typically in cramped spaces in a print unit. It furthermore provides convenient positioning of the support means 15 at various locations, such that the cleaning device 1 can be used to clean multiple anilox rolls in multiple print units.

The support means 15, in particular the telescopic beams 17, can be detachably coupled to the environment of the anilox roll 4 by means of magnetic attachment means 18. Such magnetic attachment means 18 can be attached to the print unit 2, and can be detached after the cleaning process, to remove the cleaning device 1 form the print unit. The telescopic beams 17 are hingebly connected to either of the posts 19,20 for extra degrees of freedom. The connection can for example be established by means of a ball joint.

The cleaning head 3 is supported by the cleaning head carrier 14, i.e. the cleaning head 3 is provided above the guiding rail 6 with respect to the support surface 16.

It is also possible to position the cleaning head 3 below the guiding rail 6 with respect to the support surface 16, or anywhere in between the guiding rail members 7,8.

The cleaning head 3 can be provided with cleaning medium by a supply pump from a cleaning medium container to an inlet 22 of the cleaning head. A flexible conduit can conduct the cleaning medium from the container to the cleaning head 3. The cleaning head is further provided with a sensor 23. The sensor is embodied as an optical sensor which can measure the distance between the outer surface of the anilox roll 4 and the cleaning head 3. It can further more measure the position of the cleaning head carrier 14 on the guiding rail 6. Fig. 2A shows a perspective view of the cleaning head 3 being depicted as partly transparent to show the internal configuration of the channels. Fig. 2A shows cleaning medium channel 101 highlighted. The cleaning head 3 comprises a housing 110 provided with a cleaning medium inlet 102 which can be coupled to a conduit for conducting cleaning medium from a container to the cleaning head. The cleaning medium channel 101 is bifurcated to debouch into a plurality of outlet openings 103. The outlet openings 103 are located at a washing side 104 of the cleaning head, in a central part thereof. The washing side 104 of the cleaning head 3 is substantially rectangular. This creates a compact cleaning head adapted to the shape of the anilox roll 4. During inline cleaning, the anilox roll is rotated around its central axis. A rectangular shape of the washing side 104 provides a large coverage of the outer surface of the anilox roll optimised to the rotational direction of the anilox roll. The outlet openings 103 are furthermore arranged into an array, forming the first array of outlet openings, extending in one dimension. In use, during inline cleaning, the washing side 104 is positioned close to the outer surface of the anilox roll 4, such that the central axis of the anilox roll 4 is parallel with the extension dimension of the array of outlet openings 103. Each of the outlet openings 103 may further include a nozzle for creating a jet under influence of the under pressure supplied cleaning medium.

Fig. 2B also shows a perspective view of the cleaning head 3 being depicted as partly transparent to show the internal configuration of the channels. Fig. 2B shows a further channel 105 highlighted. The further channel 105 can be arranged to extract or to supply cleaning medium or water or an additive to/form the anilox roll 4. In the embodiment of Fig. 2B, the further channel 105 is arranged to supply water to the anilox roll 4. The water is preferably heated, preferably approximately 50°C. The further channel 105 comprises an inlet 106, connectable to a conduit which can conduct water from a container or water supply to the cleaning head. The further channel 105 also bifurcates to debouch into several further openings 107. The further openings 107 are outlet openings which are configured substantially trapezoidal, diverting towards the opening 107. The further openings 107 are provided in the central part of the washing side 104 of the cleaning head 3. The further openings 107 are furthermore arranged in an array, forming the second array of outlet openings, extenchng in one dimension parallel to the array of cleaning medium outlet openings 103. Accordingly, in use, during inline cleaning, the orientation of the cleaning head 3 is such that a cell on the anilox roll, due to the rotation of the anilox roll around its central axis, encounters the cleaning medium outlet openings 103 before

encountering the further openings 107. It can be advantageous to supply water to the anilox roll through the outlet openings 107, and in a second step apply cleaning medium through the cleaning medium outlet openings 103. The anilox can subsequently be rinsed with water through the further openings 107. It is preferred to apply water to the anilox roll through the outlet openings 107 under pressure, for optimal cleaning and rinsing. Water is preferably applied under a pressure of approximately 90-100 bar. Fig. 2C also shows a perspective view of the cleaning head 3 being depicted as partly transparent to show the internal configuration of the channels.

Fig. 2C shows an extraction channel 108 highlighted. The cleaning head 3 comprises an extraction channel outlet 109 provided centrally in the housing 110 of the cleaning head 3. The extraction channel 108 also bifurcates to debouch into a plurality of extraction openings 111, wherein the extraction openings 111 are arranged at a peripheral part of the washing side 104 of the cleaning head 3. It is preferred that the extraction openings 111 have substantially the same size, and that the extraction path from the extraction opening 111 through the extraction channel 109 to the extraction channel outlet 109, is substantially the same for all extraction openings 111, to create an equal extraction on all sides at the washing side 104 of the cleaning head 3. The extraction openings 111 are elongated extending in a circumferential direction of the washing side 104 of the cleaning head 3, such that the central part of the washing side 104 is substantially surrounded by the extraction openings 111. It is envisioned that the extraction openings 111 can be adjoined to create a single

extraction opening, surrounding the central part of the washing side. An extraction pump may extract cleaning medium from the anilox roll 4 through the extraction openings 111. During inline cleaning, the washing side 104 of the cleaning head 3 and the anilox roll 4 define a gap such that the extraction pump can suck in air from the exterior of the cleaning head 3, through the gap, into the extraction channel 108 through the extraction openings 111. This creates an air flow from the exterior of the cleaning head 3 to the extraction openings, such that airborne droplets, within the housing 110 of the cleaning head 3 and from in the air exterior from the cleaning head, can be carried by the airflow to be extracted. The extraction pump can further extract cleaning medium, ink remnants and other foul, from the anilox roll, preferably such that the surface of the anilox roll is substantially cleared from any fluids when it exits the area covered by the cleaning head 3.

Fig. 2D shows a perspective view of the cleaning head 3, comprising a main piece 112 and a mouthpiece 113. The mouthpiece 113 and the main piece 112 can be detachably coupled to one another, such that the mouthpiece 113 is interchangeable with another mouthpiece. At the washing side 104 of the cleaning head 3, the mouth piece is concave to match the convex shape of the anilox roll 4. As such, the mouthpiece 113 can be interchanged with another mouthpiece having a different concave washing side matched to a differently sized anilox roll, allowing positioning of washing side close to the anilox roll. For optimal cleaning, the washing side of the cleaning head is preferably brought to approximately 0.4 mm from the outer surface of the anilox roll. The mouthpiece 113 comprises the extraction openings 107 and forms, when coupled to the main piece 112, the cleaning head 3. The mouth peace 113 also forms an extension of the extraction channel 108 when coupled to the main piece 112. As such, the mouthpiece also confines the outflow of cleaning medium from the outlet openings and directs it towards the anilox roll 4.

Moreover, the extraction openings 111 are positioned closer to the anilox roll 4 than the outlet openings 103 and further openings 107 to create optimal extraction of cleaning medium form the anilox roll 4.

Fig. 3 shows a view of the washing side 104 of another embodiment of the cleaning head 3. The washing side 104 is essentially rectangular shaped and comprises a central part 120 and a peripheral part 121. The central part 120 of the washing side 104 comprises the at least one outlet opening 103, in this embodiment seven circular shaped outlet openings 107 which are arranged into the first 122 array. The first array 122 of outlet openings extends essentially along the whole length of the washing side 104. The outlet openings 103 can for example be provide with a nozzle.

The central part 120 also comprises the at least one further opening 107. In the embodiment of Fig. 2E 3 further openings are provided arranged in a second array 123, being parallel to the first array 122. The further openings 107 are rectangular shaped extending in the direction of the array, parallel to the first array 122. In the embodiment illustrated in Fig. 3, the washing side comprises three further openings 107. It is anticipated, that the washing side can comprise a different number of further openings 107.

In use of the cleaning device 1, during inline cleaning of an anilox roll 4, the washing side 104 of the cleaning head 3 is brought close to the outer surface of the anilox roll 4, such that the first 122 and second array 123 are parallel to the central axis of the anilox roll 4. Accordingly, by rotation of the anilox roll 4, the outer surface of the anilox roll 4 moves by the washing side 104 of the cleaning head 3, to traverse a first one of the first 122 and second array 123, and subsequently traverse a second one of the first 122 and second array 123. In the illustrated embodiment, the cleaning head 3 can be oriented such that, in the direction of travel of the outer surface of the anilox roll 4, the first array 122 of outlet openings is traversed first, and the second array 123 is traversed second. It is preferred to clean the anilox roll by applying heated water under pressure onto the outer surface of the anilox roll, in order to pre-clean the anilox roll and to warm-up the anilox roll. Said water is applied through the further outlet openings 107 of the second array 123. In a second step, a cleaning medium is applied onto the outer surface of the anilox roll through the first array 122 of outlet openings. The cleaning medium can be water-based and/or solvent-based, to deep clean the cells of the anilox roll. I third step, after substantially the whole surface has been affected by the cleaning medium, the anilox roll is rinsed with water which applied through the second array 123 of outlet openings 107. During every step, water and/or cleaning medium is extracted from the anilox roll, through the extraction openings 111 in the peripheral part 121 of the washing side 104 of the cleaning head 3. It is envisioned that, in another embodiment, the second array 123 of further openings 107 may also comprise extraction openings for extracting cleaning medium from the anilox roll 4. It is anticipated that the three-step cleaning process can be executed three separate cycles or in a single cycle of the cleaning head 3 along the anilox roll, i.e., water and cleaning medium may be applied to the anilox roll separately in every step or simultaneously.

The peripheral part 121 of the washing side 104 comprises the at least one extraction openings 111. In the embodiment of Fig. 2E there are 12 extraction openings 111 provided. The extraction openings 111 are rectangular shaped, extending in a direction of the perimeter of the washing side 104, such that the extraction openings essentially surround the central part 120 of the washing side 104. It is envisioned that the extraction openings 111 can be merged into a single extraction opening and that the single extraction opening can surround the central part 120 of the washing side 104.

In the description above, it will be understood that when an element such as layer, region or substrate is referred to as being“on” or“onto” another element, the element is either directly on the other element, or intervening elements may also be present. Also, it will be understood that the values given in the description above, are given by way of example and that other values may be possible and/or may be strived for.

Furthermore, the invention may also be embodied with less components than provided in the embodiments described here, wherein one component carries out multiple functions. Just as well may the invention be embodied using more elements than depicted in the Figures, wherein functions carried out by one component in the embodiment provided are distributed over multiple components.

It is to be noted that the figures are only schematic representations of embodiments of the invention that are given by way of non-limiting examples.

For the purpose of clarity and a concise description, features are described herein as part of the same or separate embodiments, however, it will be appreciated that the scope of the invention may include embodiments having combinations of all or some of the features described. The word‘comprising’ does not exclude the presence of other features or steps than those listed in a claim. Furthermore, the words 'a' and 'an' shall not be construed as limited to 'only one', but instead are used to mean 'at least one', and do not exclude a plurality.

A person skilled in the art will readily appreciate that various parameters and values thereof disclosed in the description may be modified and that various embodiments disclosed and/or claimed may be combined without departing from the scope of the invention.