Abstract: In a method for printing a digital image in swaths with a swath time corresponding to the width of the digital image on the image receiving medium in the main scanning direction, the print controller issues a trigger that a spitting action for at least part of the printing elements of the print head needs to be performed. A swath time of subsequent swaths is gradually increased until the print head reaches a maintenance tray at a side of the print surface. The print head stays at the maintenance tray until air between the print head and the maintenance tray has approximately reached a standstill. Then, at least part of the printing elements of the print head are spitting marking material in the maintenance tray. After the spitting, the swath time of subsequent swaths is gradually decreased until the swath time is corresponding again with the width of the digital image on the image receiving medium in the main scanning direction. A digital inkjet printer is configured to perform the method.

Abstract: To provide an adjusting method for a printing apparatus, and the printing apparatus, capable of appropriately adjusting drive voltages of heads even when printing conditions are changed, this invention can appropriately acquire adjusted voltages of the heads even when printing conditions are changed. That is, according to this invention, a construction is configured to change an adjustable range of head drive voltages with a printing mode. This invention acquires the adjustable range corresponding to the printing mode set by referring to a table Ti. Consequently, the adjusted voltages of the heads can be determined within the adjustable range suited to each printing mode.

Abstract: A liquid ejecting apparatus includes a mode controller that controls execution of a first mode in which an operation of the liquid ejecting head is controlled under pressurization at first pressure by the pressurizing mechanism and depressurization at second pressure by the depressurizing mechanism and execution of a second mode in which the operation of the liquid ejecting head is controlled under pressurization at third pressure by the pressurizing mechanism and depressurization at fourth pressure by the depressurizing mechanism. To switch from the execution of the first mode to the execution of the second mode, the mode controller gradually changes, from the first pressure to the third pressure, pressure at which the pressurization operation is performed by the pressurizing mechanism, and gradually changes, from the second pressure to the fourth pressure, pressure at which the depressurization operation is performed by the depressurizing mechanism.

Abstract: Methods and apparatus are described herein for measurement of droplets dispensed from a printhead of an inkjet printer onto a substrate. An inkjet printer described herein comprises a printhead assembly comprising a printhead and an imaging system, the imaging system comprising a camera and a strobed LED source; and a deposition unit for positioning a substrate to receive droplets dispensed from the printhead and for imaging the droplets using the imaging system and the strobed LED source. Methods described herein comprise dispensing droplets of a liquid from a printhead of a printhead assembly of an inkjet printer onto a substrate; positioning the substrate with respect to an imaging system coupled to the printhead assembly, the imaging system comprising a camera and an LED light source; and imaging the droplets on the substrate by relatively scanning the substrate and the imaging system and strobing the LED light source.

Abstract: An inkjet printer configures the printheads in a printhead module in an orientation that attenuates a temperature differential between the ink drops ejected by adjacent printheads at a stitch area between the adjacent printheads. The reduced temperature differential helps ensure that the contrasts between the two inks ejected by the adjacent printheads is sufficiently similar that image quality is not adversely impacted.

Abstract: A power supply control apparatus comprises a first power supply supplying power to a controller and a second power supply supplying power to an operation unit and a power controller. The operation unit receives an operation for switching the first power supply on and off. The power controller is operable to turn on the first power supply according to the signal from a timer or the operation by the operation unit, and to turn off the first power supply according to a state of the controller. The controller, upon at least either of the operation by the operation unit or the signal from the timer, performs a setting to the timer of a time at which to turn on the power from the first power supply or a time at which to turn off the power from the first power supply.

Abstract: There is provided a technology that enables reduction of an amount of data to be processed in testing a printed image printed on a printing medium. A printing apparatus includes a printing unit, a camera, and an image-data output unit. The printing unit is capable of printing plural categories of test patterns on the printing medium. The camera captures an image of a test pattern printed on the printing medium, and outputs acquired image data to the image-data output unit. The image-data output unit reduces an amount of data of the image data output from the camera, in accordance with the category of the test pattern, and outputs acquired image data to a test apparatus.

Abstract: An occurrence of leakage is prevented. An inkjet head jets ink. The inkjet head is provided with a head main body, a cooling pipe, a jet-side coupling member, and a cooling-side coupling member, wherein the head main body has a jet flow path through which the ink passes, the cooling pipe has a cooling flow path through which the ink passes as a cooling medium for cooling a drive circuit, the jet-side coupling member is coupled to the head main body, a jet-side branch path branches from an ink flow path into which the ink inflows from an outside of the inkjet head, or from which the ink outflows, the jet-side branch path is communicated with the jet flow path, the jet-side branch path is provided to the jet-side coupling member, and the cooling-side coupling member is coupled to the jet-side coupling member, and is provided with a cooling-side branch path which branches from the ink flow path, and which is communicated with the cooling flow path.

Abstract: A flow rate distribution of flow paths is controlled. An inkjet head jets ink. The inkjet head is provided with a head main body having a jet flow path through which the ink passes, a cooling pipe having a cooling flow path through which the ink passes as a cooling medium for cooling a drive circuit, and a throttle member for controlling a flow path resistance of the cooling flow path.

Abstract: A head chip, a liquid jet head, a liquid jet recording device, and a method of manufacturing a head chip each capable of suppressing the variation in ejection performance between the ejection channels without changing the shape of a channel (a drive wall) are provided.

Abstract: A liquid discharge apparatus includes a liquid discharge head, a stage, a guide rail, and an opening-and-closing cover. The liquid discharge head discharges a liquid to a recording medium. The stage moves in a vertical direction to move the recording medium on the stage. The guide rail holds the stage. The stage is movable in a conveyance direction intersecting the vertical direction. The opening-and-closing cover is slidable in one of the conveyance direction and a main scanning direction intersecting both the conveyance direction and the vertical direction. The opening-and-closing cover includes a retraction portion retractable above the stage.

Abstract: The cleaning liquid supply mechanism ejects the cleaning liquid to an ejection target that is one of the cleaning roller and the cap. In particular, the cleaning liquid supply mechanism switches the ejection target between the cap and the cleaning roller and ejects the cleaning liquid to the ejection target. Specifically, if the cap is set as the ejection target, the cleaning liquid is ejected from the cleaning liquid supply mechanism directly to the cap as the ejection target. If the cleaning roller is set as the ejection target, the cleaning liquid is ejected from the cleaning liquid supply mechanism directly to the cleaning roller as the ejection target.

Abstract: A technique allows sucking ink adhering to the lower surface of a head and preventing the ink from being sucked out from the inside of nozzles of the head. The printer includes a head that ejects ink and a maintenance unit that performs maintenance of the head. The head has a lower surface that includes a nozzle face provided with a plurality of nozzles and side faces located adjacent to the nozzle face. The maintenance unit includes a cleaning block that sucks the ink from the lower surface of the head. The cleaning block has an upper surface that includes a first region that faces the nozzle face and second regions that face the side faces. The suction force acting on the first region is smaller than the suction force acting on the second regions. This reduces the possibility that the ink is sucked out from the inside of the nozzles of the head.

Abstract: This invention aims to propose a structure excellent in the maintenance operability of a cleaning member in a printing apparatus provided with the cleaning member for cleaning at least one of a wiper and a cap. In a printing apparatus according to the invention, a cleaning member for cleaning a wiper or a cap of a maintenance part is integrated with a printing head in a relative movement between the printing head and the maintenance part and arranged to at least partially overlap a movement path of the object to be cleaned with respect to the printing head and moves to outside the conveyance path integrally with the printing head when the printing head is moved from the inside position to the outside position.

Abstract: A printing apparatus includes a housing, a medium support unit having a support surface supporting a medium, and a printing unit configured to perform printing on the medium supported by the support surface. The housing accommodates the medium support unit and the printing unit. The medium support unit includes a position adjustment unit configured to adjust a position of the support surface in an intersecting direction intersecting the support surface. The position adjustment unit can move the support surface from outside the movement range to within the movement range when the printing is not being performed by the printing unit and the head is disposed at a retracted position.

Abstract: A printing apparatus includes a medium support unit having a support surface that supports at least a printing region of a medium, a medium accommodation unit configured to store a region of the medium that is not supported by the support surface, a head configured to eject a liquid onto the medium supported by the support surface, and a head moving unit configured to move the head. The medium support unit is configured not to move in a direction parallel to the support surface, and the head moving unit moves the head in a direction parallel to the support surface.

Abstract: A liquid discharge apparatus includes a liquid discharge head, a cap, a waste liquid channel, a wiper, a cleaner, and a cleaning liquid drainage. The liquid discharge head has a nozzle, from which a liquid is discharged, on a nozzle face. The cap caps the nozzle to suck a waste liquid from the nozzle. The waste liquid channel is connected to the cap and has a waste liquid outlet from which the waste liquid is drained. The wiper wipes the nozzle face. The cleaner applies a cleaning liquid to the wiper. The cleaning liquid drainage drains the cleaning liquid applied to the wiper to the waste liquid outlet.

Abstract: A technique allows satisfactorily cleaning ejection heads with a cleaning liquid while protecting ink meniscus in nozzles. A printer includes an ejection head, a cleaning-liquid block, and a receptacle. The ejection head has an ink ejecting plane that includes nozzles as openings and ejects ink from the nozzles. The cleaning block has a head opposing plane that includes an ejection hole as an opening. The cleaning block ejects a cleaning liquid in an inclination direction inclined relative to the ink ejecting plane. The receptacle is located below the cleaning block and receives the cleaning liquid ejected from the ejection hole.

Abstract: An image forming apparatus includes a recording head, a controller, and a correction processor. The controller determines a nozzle corresponding to an image to be printed, and causes the recording head to eject ink from the nozzle. The correction processor detects an abnormally ejecting nozzle out of the nozzles in the recording head, and designates the abnormally ejecting nozzle as a target nozzle, and performs correction processing based on a status of the target nozzle, to the image. The correction processor also adds the detected abnormally ejecting nozzle to history data, each time a detecting operation is performed, and selects a nozzle included in the history data as an additional target nozzle, out of the nozzles that have not been detected as the abnormally ejecting nozzle, through the current detecting operation, and adds the selected nozzle to the target nozzle.

Abstract: An inkjet printer includes: an inkjet head configured to eject ink to a print medium being conveyed; a mist collector including at least a suction port configured to suck air from a side of the inkjet head on which the print medium passes; and a controller configured to control the mist collector. A space on the side of the inkjet head on which the print medium passes is an open space in which nothing but the print medium passing is arranged within a prescribed distance from the inkjet head. The controller is configured to control the mist collector to perform a mist collection operation of sucking air containing ink mist via the suction port in a state where the print medium and the inkjet head are facing each other.

Abstract: A liquid discharge apparatus includes a first liquid discharge unit including a first liquid discharge head that moves in a main scanning direction to discharge a liquid onto a recording medium conveyed in a conveyance direction orthogonal to the main scanning direction, a second liquid discharge unit at a different position with the first liquid discharge unit in the conveyance direction and including a second liquid discharge head that moves in the main scanning direction parallel to the first liquid discharge head to discharge a liquid onto the recording medium, a first airflow generator between the first liquid discharge unit and the second liquid discharge unit in the conveyance direction to generate an airflow flowing in the main scanning direction, and a partition plate between the first airflow generator and the second liquid discharge unit in the conveyance direction.

Abstract: A sub-controller (20), controller (30), fluid supply system and apparatus for printing and a method for printing. Provided is a processor controlled sub-controller (20) for controlling the fluid pressure in one or more droplet ejection heads (60); wherein said controller (30) is configured to receive a droplet ejection head movement profile for each of said one or more droplet ejection heads (60), determine a respective induced fluid pressure profile at one or more predetermined locations for each of said one or more droplet ejection heads (60) using the respective droplet ejection head movement profile; and generate respective pressure correction data for each of said one or more droplet ejection heads based on the respective induced fluid pressure profile and a predetermined pressure window to be maintained at said one or more droplet ejection heads (60).

Abstract: An individual flow path that communicates with a nozzle, a supply side common liquid chamber for supplying ink to the nozzle, a recovery side common liquid chamber for recovering the ink not discharged from the nozzle, an inlet that communicates with the supply side common liquid chamber, an outlet that communicates with the recovery side common liquid chamber, a first bypass flow path, and a second bypass flow path are provided, in which the inlet and the outlet are disposed between the first bypass flow path and the second bypass flow path, and a flow path resistance of the first bypass flow path and a flow path resistance of the second bypass flow path are different from each other.

Abstract: A liquid supplying apparatus having a tank with a hole, a reservoir chamber to store a portion of liquid in the tank, and a flow path to store another portion of the liquid in the tank, is provided. The flow path connects the reservoir chamber and the hole. The flow path has a first funnel section to reduce a cross-sectional area of a part of the flow path. The first funnel section is located at a position equal to or higher than a surface of a predetermined maximum amount of the liquid storable in the tank in a usable posture. The first funnel section creates a meniscus with the liquid stored in the tank in an X1-rotated posture, in which the tank is rotated about a first axis by a first angle from the usable posture.

Abstract: A system, having a liquid container and a case, is provided. The case has a tubular body extending along a mounting/demounting direction and entering the liquid container through a supply port, a liquid receiver located below an end of the tubular body, and a movable member contacting and being moved by the liquid container moving along the mounting/demounting direction. The liquid receiver is movable between a first position, at which the liquid receiver is one of in contact with and in proximity to the end of the tubular body, and a second position, at which the liquid receiver is separated farther from the end of the tubular body than the first position. The movable member moves the liquid receiver from the first position to the second position by contacting and being moved by the liquid container moving in the mounting orientation.

Abstract: A cartridge configured to be inserted in a first direction into a case having a plurality of engagement portions is provided. The cartridge has a body and a key member. The body has a chamber for storing a printing agent. The key member is located on the body at a position associated with a type of the printing agent stored in the chamber and is configured to engage with a corresponding one of the plurality of engagement portions of the case. The key member has a surface facing a second direction opposite to the first direction. The surface is configured to contact the corresponding one of the plurality of engagement portions.

Abstract: A printing-agent container, having a container body, an outflow port, and an identifying portion, is provided. The container body has a chamber for containing a printing agent. Through the outflow port, the printing agent flows out of the chamber. The identifying portion is provided to the container body correspondingly to a type of the printing agent contained in the chamber of the container body. The identifying portion has an inner surface defining the chamber.

Abstract: In a board that includes a plurality of contact portions that are arranged to contact corresponding apparatus-side terminals when the board is mounted in a printing apparatus, some contact portions are disposed in a first region, and the remaining contact portions are disposed in a second region. The some contact portions include a first contact portion, a second contact portion, a third contact portion, and a fourth contact portion. The remaining contact portions include a fifth contact portion. The some contact portions are arranged in a first pattern in the first region and the remaining contact portions are arranged in a second pattern in the second region, and the first pattern is asymmetrical to the second pattern with respect to a first virtual line.

Abstract: A fluid-ejection die cartridge includes a cartridge body. The fluid-ejection die cartridge includes a fluid-ejection die fluidically attached to the cartridge body. The fluid-ejection die is to eject fluid. The fluid-ejection die cartridge includes a stamped nanoceramic layer on an exposed fluid-ejection nozzle plate of the fluid-ejection die attached to the cartridge body.

Abstract: There is provided a liquid consuming apparatus including: a tank having a liquid storing chamber, an erected wall through which the liquid inside the liquid storage chamber is visible from outside of the tank, and an inlet which is formed to penetrate through the erected wall and via which the liquid is poured into the liquid storage chamber; a liquid consuming section which consumes the liquid stored in the liquid storing chamber; and a cover. A transmitting section and a checking section are formed in an upper surface, of the cover, under a condition that the cover is in the exposure position, the transmitting section configured to transmit information optically to a user of the liquid consuming apparatus and the checking section configured to prevent the liquid moving on a particular surface of the cover from arriving at the transmitting section.

Abstract: A fluid cartridge having a plastic fluid body, a bottom wall having a fluid supply opening therein. An insert is adhesively fastened to the bottom wall. The insert has a fluid supply slot therein corresponding to the fluid supply opening in the bottom wall, a die bond surface adjacent to the fluid supply slot for adhesively fastening an ejection head chip thereto, and a plurality of air vents adjacent to the die bond surface. The insert is a material selected from an epoxy molding compound and a ceramic material. An ejection head chip is adhesively fastened to the die bond surface of the insert.

Abstract: A liquid ejection apparatus includes an ejection head that ejects a liquid, a container that stores the liquid, and a reservoir that supplies the liquid to the ejection head and stores the liquid supplied from the container. The reservoir includes a first chamber that stores the liquid, a second chamber that is arranged downstream of the first chamber and stores the liquid, and a first flow path and a second flow path that communicate the first and second chambers with each other. A communication port between the first chamber and the second flow path is located lower than a communication port between the first chamber and the first flow path in a usage posture of the liquid ejection apparatus. The second flow path is configured so that a rate of a pressure loss increases as a flow rate of the liquid flowing inside the second flow path increases.

Abstract: A liquid discharge apparatus including a head configured to discharge a liquid, a chamber configured to contain the head, a circulation system configured to circulate a gas inside the chamber, an exhaust system configured to operate to exhaust the gas to an outside of the chamber, a filter provided in the circulation system and configured to remove a removal target contained in the gas, a detection unit configured to indirectly detect the removal target by detecting a detection target that is contained in the gas and different from the removal target, and a controller configured to operate the exhaust system when a concentration of the detection target detected by the detection unit is not lower than a threshold.

Abstract: To provide an inkjet recording method capable of recording images with good ink ejection stability and excellent abrasion resistance while circulating ink between the ink storage portion and the recording head over a long period of time. An ink jet recording method in which an aqueous ink is ejected from a recording head and applied to a recording medium to record an image, the ink jet recording method uses an ink jet recording apparatus equipped with an ink circulation flow path for circulating the aqueous ink from an ink storage portion to the recording head, including the ink storage portion for storing the aqueous ink, the recording head of an ink jet system for ejecting the aqueous ink, a cooling portion for cooling the aqueous ink, a heating portion for heating the aqueous ink, and a pump for circulating the aqueous ink.

Abstract: Techniques are provided for printing white underbase image data and highlight white image data in one pass using digital printing technologies. The techniques include increasing the white ink in the white only (or near white only) areas of the image data by combining the white underbase image data and the white ink (or near white ink) image data.

Abstract: An abnormal ejection detection portion detects an abnormal ejection nozzle in a print head based on a read test image read from a sheet with a test pattern formed thereon. When a plurality of abnormal ejection nozzles are detected and the plurality of abnormal ejection nozzles include two consecutive abnormal nozzles corresponding to two consecutive pixels in the read test image, a correction processing portion performs increase correction on an ink ejection amount of consecutive adjacent nozzles adjacent to the two consecutive abnormal nozzles and performs decrease correction on an ink ejection amount of secondary adjacent nozzles adjacent to the consecutive adjacent nozzles.

Abstract: A heat generating member includes: a hollow cylindrical part that is rotatable about a rotation axis and extends in an axial direction; a first heat generating component provided on an inner surface of the cylindrical part and configured to generate heat when energized; a first connecting component provided on an inner side relative to the cylindrical part and electrically connected to the first heat generating component, the first connecting component being rotatable together with the cylindrical part; a second connecting component provided on a further inner side relative to the cylindrical part than the first connecting component and electrically connected to a power source, the second connecting component being rotatable relative to the cylindrical part; a rotary supporting component that electrically connects the first connecting component and the second connecting component to each other and supports the first connecting component while allowing the first connecting component to rotate relative to the s

Abstract: An embodiment of the present invention provides a printer configured to print on a print medium. The printer includes a thermal head and a control unit. The thermal head has a plurality of heating elements that are arranged in a line. The control unit is configured to control thermal energy to be applied to the plurality of heating elements, in accordance with information based on image data. The information includes whether to apply a pulse of energizing current in each of a plurality of periods being preset during a scanning line time for one line. The plurality of periods is set in an order from a long period to a short period during the scanning line time.

Abstract: The embodiments of the disclosure provide an image data processing method for laser imaging, a computer device and a computer-readable storage medium. In the embodiments, in case where the gap distance corresponding to a previous laser is not an integer multiple of the preset width of pixel row, the image resolution for a scan area associated with a next adjacent laser is increased to the second resolution to decrease the width of pixel row in the associated scan area, thereby more pixel rows may be obtained in the same area in the raw scan image, and the pixel rows closer to the position actually scanned by the laser spot may be selected as the target pixel rows, which may decrease the deviation between the position of the pixel row actually scanned by the laser and the theoretical position of the pixel row, and further improve the laser scan imaging accuracy.

Abstract: A coating method includes applying a first ink on a print object, rotating the print object to a substantially perpendicular position, and applying a second ink on the first ink on the print object.

Abstract: An example printer device includes a chassis. The example printer device further includes a paper path component along which paper is output from the chassis. The example printer device further includes a display screen movable between a stored position and a deployed position, the paper path component moving as the display screen moves.

Abstract: Provided is a technique that enables proper sorting of discharged print media by suppressing curling of each of the print media sufficiently. A determining unit determines a curling suppressing operation to be executed such that in a case where sorting operation is executed, the suppressing operation having a higher effect of suppressing curling is executed than in a case where the sorting operation is executed. Then, a print control unit controls a print head to perform printing on print media while executing the suppressing operation determined by the determining unit.

Abstract: Examples relate to methods to heat a print agent deposited on a print agent, print an image on a print media and heating systems for a heating a print agent deposited on a print media. A heating system comprises a radiation emitter to irradiate a print agent deposited on a print media, a reflector to reflect a radiation emitted by the radiation emitter back to the radiation emitter, and a displacing member to shift the heating system between a pre-heating position wherein the radiation reflected back to the radiation emitter has a higher magnitude and a heating position wherein the radiation reflected back to the radiation emitter has a lower magnitude.

Abstract: Provided is an ink jet recording method by which even when a recording medium having a relatively small basis weight or a highly water-absorbing recording medium is used, an image can be recorded while the occurrence of cockling is suppressed. The method is an ink jet recording method including recording an image on a recording medium with an ink jet recording apparatus including a blowing portion configured to blow air to the recording medium to dry an aqueous ink. The blowing portion includes conveying members and a blowing device. The conveying members include a first conveying member free of an adsorption mechanism and a second conveying member including an adsorption mechanism in the stated order. The aqueous ink includes a water-soluble organic solvent.

Abstract: A medium mending device includes a heating component configured to heat a medium having an image recorded, and a pressing component positioned against the heating component and configured to press the medium that is to be nipped between the pressing component and the heating component, the pressing component pressing the medium with such a pressure as to squash any flaws in the medium.

Abstract: A printing device includes a printing section and a tray support section. The printing section performs printing on a medium. The tray support section supports a tray. The tray includes a placement surface configured to support the medium. The tray support section includes a positioning section that determines a placement position of the medium with respect to the tray.

Abstract: There is provided a tank including a liquid storage chamber and an outlet. The liquid storage chamber includes a base portion and a protruding portion, the base portion includes a first lateral wall and a second lateral wall which faces the first lateral wall in a left-right direction, the protruding portion protrudes from the second lateral wall in a direction away from the first lateral wall in the left-right direction, and the left-right direction is defined based on a usable posture in which the tank is disposed such that a lower surface of the liquid storage chamber is located below an upper surface of the liquid storage chamber. A distance between the outlet and the second lateral wall in the left-right direction is smaller than a distance between the outlet and the first lateral wall in the left-right direction.

Abstract: The present teachings relate to various embodiments of an hermetically-sealed gas enclosure assembly and system that can be readily transportable and assemblable and provide for maintaining a minimum inert gas volume and maximal access to various devices and apparatuses enclosed therein. Various embodiments of an hermetically-sealed gas enclosure assembly and system of the present teachings can have a gas enclosure assembly constructed in a fashion that minimizes the internal volume of a gas enclosure assembly, and at the same time optimizes the working space to accommodate a variety of footprints of various OLED printing systems. Various embodiments of a gas enclosure assembly so constructed additionally provide ready access to the interior of a gas enclosure assembly from the exterior during processing and readily access to the interior for maintenance, while minimizing downtime.

Abstract: A liquid discharge apparatus includes an apparatus body, a liquid discharge unit, a first ventilation channel a cover, and a second ventilation channel. The liquid discharge unit discharges a liquid. The first ventilation channel in the apparatus body has a first end opened to an interior of the apparatus body in a first direction. The cover is movable between an open position and a closed position to operably close the apparatus body. The second ventilation channel connected to the cover has a second end opened to the interior of the apparatus body in a second direction different from the first direction. The cover at the closed position causes the first end of the first ventilation channel to be connected to the second end of the second ventilation channel.

Abstract: A printing system comprising a flexographic printing machine comprising at least one impression cylinder, on which the material in sheet form to be printed is wound and around which at least one printing station is arranged. Each printing station comprises a plate cylinder, which is provided with a graphic element, and an anilox roller. Downstream of each printing station there is at least one drying unit for the inks which emits at least one first air flow and aspirates at least one second air flow; there are also elements for acquiring a coverage value of the graphic element present on the plate cylinder of each printing station and elements for automatically adjusting a flow rate of the first air flow and of the second air flow as a function of the coverage value of the graphic element acquired by the acquisition elements.