EP4153431B1 - Device and method for suctioning ink mist - Google Patents

Device and method for suctioning ink mist Download PDF

Info

Publication number
EP4153431B1
EP4153431B1 EP22721693.4A EP22721693A EP4153431B1 EP 4153431 B1 EP4153431 B1 EP 4153431B1 EP 22721693 A EP22721693 A EP 22721693A EP 4153431 B1 EP4153431 B1 EP 4153431B1
Authority
EP
European Patent Office
Prior art keywords
recording medium
transport direction
constriction
printing
ink mist
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
EP22721693.4A
Other languages
German (de)
French (fr)
Other versions
EP4153431A1 (en
Inventor
Albrecht Gerstner
Frank Freudenberg
Christian KÜRMEIER
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Canon Production Printing Holding BV
Original Assignee
Canon Production Printing Holding BV
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Canon Production Printing Holding BV filed Critical Canon Production Printing Holding BV
Publication of EP4153431A1 publication Critical patent/EP4153431A1/en
Application granted granted Critical
Publication of EP4153431B1 publication Critical patent/EP4153431B1/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/005—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
    • B41J2/01—Ink jet
    • B41J2/17—Ink jet characterised by ink handling
    • B41J2/1714—Conditioning of the outside of ink supply systems, e.g. inkjet collector cleaning, ink mist removal

Definitions

  • the invention relates to a device and a corresponding method for extracting ink mist.
  • Inkjet printing devices can be used to print on recording media such as paper.
  • one or more nozzles are used in a printing unit of the printing device to fire drops of ink onto the recording medium and thus produce a desired printed image on the recording medium.
  • An inkjet printing device typically further comprises a drying unit in order to dry the recording medium after applying the printed image and thereby fixing the applied ink on the recording medium.
  • an ink mist i.e. an aerosol with ink particles
  • an aerosol with ink particles can arise in the printing unit, which can be transported from the recording medium into the drying unit and which can lead to contamination there.
  • JP 2010 - 284 892 A , JP 2010- 143 060 A , JP 2010- 201 874 A , US 2016/ 0 271 950 A1 , EP3081382 and JP2010284892 disclose a suction device for ink mist in an inkjet printing system, the suction device being downstream of a bottleneck after the printing unit in the transport direction.
  • the disadvantage here is that there is a possibility of contamination for the recording medium and the printing system between the printing unit and the suction device.
  • US 2018/0001648 A1 discloses an ink mist suction device in an ink jet printing system, the suction device being arranged at the same position as a fan in the transport direction.
  • a suction device for suctioning ink mist in an inkjet printing device
  • the printing device has a printing unit for printing on a front side of a, in particular band-shaped, recording medium moved along a transport direction through the printing unit.
  • the suction device comprises a mechanical barrier which is designed to form a constriction over the front side of the recording medium, which is printed in the printing unit and is guided past the mechanical barrier in the transport direction.
  • the bottleneck forms a tunnel for the recording medium and has an extension of less than 25 mm in the transport direction.
  • the suction device comprises a blower which is designed to cause a gas flow running counter to the transport direction in the narrow area above the printed front side of the recording medium.
  • the suction device further comprises a suction unit which is set up to suck ink mist from the printed front side of the recording medium in a suction area which is arranged in front of the narrow point with respect to the transport direction.
  • the suction device can be arranged in front of the bottleneck, in particular above the suction area.
  • a method for extracting ink mist in an inkjet printing device wherein the printing device has a printing unit for printing on a front side of a recording medium moved along a transport direction through the printing unit.
  • the method includes guiding the recording medium along the transport direction through a mechanical bottleneck arranged above the front of the recording medium.
  • the method further comprises causing a gas flow to run in the narrow area opposite to the direction of transport over the printed front side of the recording medium.
  • the method also includes suctioning off ink mist from the printed front side of the recording medium in a suction area which is arranged in front of the bottleneck with respect to the transport direction.
  • the bottleneck has an extension of less than 25 mm in the transport direction, the gas flow or the purging air can effectively prevent ink mist from penetrating the area of the bottleneck.
  • the constriction has an extension in the transport direction of less than 15 mm, preferably less than 5 mm, even more preferably less than 2 mm. This is advantageous because the smaller the extension of the constriction in the transport direction, the more effectively penetration of ink mist from a boundary air layer in the vicinity of the recording medium into the area of the constriction can be prevented.
  • the mechanical barrier extends in the transport direction from the narrow point as a ramp with increasing distance to the recording medium in order to direct a gas flow from the fan against the transport direction to the narrow point. This provides an effective way to keep the ink mist away from the bottleneck.
  • the mechanical barrier breaks off against the transport direction after the narrow point, so that the gas flow of the blower against the transport direction after the narrow point leads to turbulent air turbulence, so that air from the boundary air layer is entrained perpendicular to the transport direction, as a result of which the laminar flowing boundary air layer is separated from the Record carrier replaced.
  • a significantly larger portion of the ink mist can be directed to the suction device and removed.
  • the mechanical barrier extends against the transport direction after the narrow point in a round shape as a ramp with an increasing distance from the recording medium, so that the gas flow from the blower flows laminarly after the narrow point along the round shape with an increasing vertical distance from the recording medium and thus air is entrained from the boundary air layer perpendicular to the transport direction and the laminar flowing boundary air layer detaches itself from the recording medium.
  • This can also be done in comparison to the prior art A significantly larger part of the ink mist is directed to the suction device and removed.
  • the mechanical barrier preferably extends from the narrow point in the transport direction as a ramp with a rounded shape with increasing distance. These and other ramp shapes allow an efficient supply of the gas flow from the fan to the bottleneck.
  • the printing device has a printing width transverse to the transport direction, over which the front side of the recording medium is printed in the printing unit. It is even more expedient if the bottleneck extends over the entire printing width of the printing device. In this way, almost all of the ink mist can be removed from the boundary air layer around the recording medium.
  • the gas flow caused by the fan is designed such that the ink mist in the suction area, in particular directly on the front of the recording medium, has a movement speed in the transport direction that is smaller, in particular smaller by a factor of 2 or more, than a transport speed of the recording medium.
  • a particularly large amount of ink mist can be removed from the boundary air layer in this way.
  • the blower is expediently set up to supply the gas flow to the constriction through an air duct with a thickness between 0.1 mm and 1 mm, so that the gas flow forms an air knife.
  • the sharp, fast and narrow gas stream that comes from the very narrow slot of the outflow area of the "air knife” moves according to Coanda's law by the thickness of the air knife against the transport direction of the recording medium.
  • a large amount of ambient air is also entrained from the boundary air layer near the recording medium on the outgoing side of the bottleneck.
  • the gas flow after the bottleneck causes turbulent turbulence. If the mechanical barrier extends in a round shape after the bottleneck as a ramp with increasing distance, the gas flow from the blower flows laminarly along the rounded shape after the bottleneck. This flows with increasing vertical distance to the recording medium, so that air is entrained from the boundary air layer perpendicular to the transport direction .
  • the aerosol-containing air is thus excellently lifted off the boundary air layer on the recording medium and transported away from the recording medium with the jet air.
  • a suitable suction device can absorb the aerosol-containing air and dispose of it appropriately.
  • the gap height between the recording medium and an outlet point of the air duct is preferably between 0 and 25 mm, more preferably between 1 and 10 mm, even more preferably between 1 and 5 mm. In this way, a particularly efficient effect on the boundary air layer on the recording medium can be achieved.
  • the air duct forms an angle between 10° and 80°, preferably between 20° and 70°, even more preferably between 30° and 60° to the transport direction.
  • An angle of 45° has proven to be particularly useful.
  • the printing device 100 shown is designed for printing on a sheet-shaped or sheet-shaped or plate-shaped or tape-shaped recording medium 120.
  • the recording medium 120 can be made of paper, cardboard, cardboard, metal, plastic, textiles, a combination thereof and/or other suitable and printable materials.
  • the award holder 120 is guided through the printing unit 140 of the printing device 100 along the transport direction 1, shown by an arrow.
  • the printing unit 140 of the printing device 100 includes two printing bars 102, whereby each printing bar 102 can be used for printing with ink of a specific color, for example black, cyan, magenta and/or yellow and possibly MICR ink. Different printing bars 102 can be used for printing with different inks.
  • the printing device 100 includes at least one fixing or drying unit 150, which is set up to fix a printed image printed on the recording medium 120.
  • a printing bar 102 can comprise one or more print heads 103, which may be arranged next to one another in several rows in order to print the pixels of different columns 31, 32 of a printed image onto the recording medium 120.
  • a print bar 102 comprises five print heads 103, each print head 103 printing the pixels of a group of columns 31, 32 of a print image onto the recording medium 120.
  • Each print head 103 of the printing unit 140 includes in the Fig. 1a illustrated embodiment several nozzles 21, 22, each nozzle 21, 22 being set up to fire or push ink drops onto the recording medium 120.
  • a print head 103 of the printing unit 140 can, for example, comprise several thousand effectively used nozzles 21, 22, which are arranged along several rows transversely to the transport direction 1, ie along the printing width, of the recording medium 120.
  • pixels of a line of a printed image can be printed onto the recording medium 120 transversely to the transport direction 1, ie along the width of the recording medium 120.
  • the printing device 100 further comprises a control unit 101, for example a control hardware and/or a controller, which is set up to control the actuators of the individual nozzles 21, 22 of the individual print heads 103 of the printing unit 140 in order to print the printed image depending on print data Apply recording medium 120.
  • the print data can indicate for each nozzle 21, 22, i.e. for each column 31, 32 of the print image, and for each line of the print image, whether or not ink should be ejected and, if applicable, what amount of ink should be ejected.
  • the printing unit 140 of the printing device 100 thus comprises at least one printing bar 102 with K nozzles 21, 22, which can be controlled with a specific line cycle in order to create a line that runs transversely to the transport direction 1 of the recording medium 120, with K pixels or K columns 31, 32 to print a print image onto the recording medium 120, for example with K>1000.
  • the nozzles 21, 22 are immovably or permanently installed in the printing device 100, and the recording medium 120 is guided past the fixed nozzles 21, 22 at a certain transport speed.
  • the printing device 100 can include a drying unit 150, which is set up to dry the recording medium 120 after the ink has been applied by the one or more printing bars 102 and thus to fix the applied printed image on the recording medium 120.
  • Drying unit 150 shown comprises a plurality of drying modules 160, which are arranged along a drying path on both sides of the, typically web-shaped, recording medium 120, and which are each set up to blow a gaseous drying medium, typically heated air, onto the surface of the recording medium 120.
  • the drying section with the drying modules 160 is arranged in a housing 155 of the drying unit 150.
  • an ink mist typically arises in the printing unit 140, which includes color pigments of the one or more different inks with which printing is carried out in the printing unit 140.
  • the ink mist 170 can, as exemplified in Fig. 1c shown, are carried along by the recording medium 120 along the transport direction 1.
  • the ink mist 170 can be transported from the printing unit 140 into the subsequent drying unit 150.
  • the ink mist 170 can then lead to contamination in the housing 155, in particular on the one or more drying modules 160, of the drying unit 150, whereby the quality of the drying of the recording medium 120 can be impaired by the contamination.
  • Fig. 2 shows an exemplary suction device 200, which is arranged behind the printing unit 140 and/or in front of the drying unit 150 with respect to the transport direction 3.
  • the suction device 200 comprises a mechanical barrier 201, which forms a mechanical bottleneck 202 through which the recording medium 120 is passed.
  • the constriction 202 can have a height perpendicular to the surface, in particular perpendicular to the front, of the recording medium 120, which on the one hand is as small as possible in order to allow only the smallest possible proportion of the ink mist 170 entrained with the recording medium 120 to pass through, but which on the other hand is sufficiently large to avoid collisions with the To avoid recording medium 120.
  • the constriction 202 can, for example, have a height between 1 and 12 mm, preferably between 1 and 3 mm.
  • the bottleneck 202 has a certain length in the transport direction 1, so that the bottleneck 202 forms a tunnel for the recording medium 120.
  • the bottleneck 202 has a length that is significantly less than 25 mm. In particular, it is advantageous if the length is less than 15, more preferably less than 10 mm, in particular less than 5 mm.
  • the mechanical barrier 201 preferably extends in the transport direction from the bottleneck 202 as a ramp with increasing distance.
  • a gas stream 204 is directed from the fan 203 to the constriction 202.
  • the mechanical barrier 201 breaks off after the constriction 202, so that the gas flow 204 of the fan 203 leads to turbulent air turbulences after the constriction against the transport direction 3. In this way, air is entrained from the boundary air layer perpendicular to the transport direction, as a result of which the laminar-flowing boundary air layer detaches from the recording medium 120.
  • the suction device 200 further comprises a blower 203, which is designed to cause a gas flow 204 at the exit of the bottleneck 202, which is opposite to the transport direction 1.
  • the gas stream 204 is also referred to in this document as a blocking gas stream 204, since the gas stream 204 is designed to block the ink mist 170 entrained by the recording medium 120 in a boundary air layer at the bottleneck 202 and this boundary air layer including the ink mist 170 perpendicular to the transport direction to replace.
  • the blower 203 can be arranged behind the bottleneck 202, in particular behind the exit of the bottleneck 202.
  • the fan 203 runs transversely to the transport direction of the substrate and covers at least the width of the substrate.
  • the suction device 200 includes a suction unit 205, which is set up to suck out the ink mist 170 in front of the bottleneck 202.
  • the suction unit 205 can be arranged in front of the bottleneck 202, in particular in front of the entrance to the bottleneck 202. Furthermore, the suction unit 205 can be separate from the mechanical barrier 201 to form the Be bottleneck 202.
  • the blocking gas stream 204 causes the ink mist 170 at the entrance to the constriction 202 and/or in front of the constriction 202 to detach itself with an air movement of the blocking gas stream 204 perpendicular to the transport direction, so that the ink mist 170 is efficiently transported through a forward
  • the suction unit 205 arranged in the constriction 202 can be sucked out. This can also be achieved by a relatively small intake volume flow and/or by a relatively low intake power.
  • the suction unit 205 can have a relatively large suction opening, similar to an extractor hood, in order to suck out the ink mist 170 over a large area.
  • the suction device 200 shown can be reliably prevented from causing the ink mist 170 to contaminate the subsequent drying unit 150.
  • the suction 200 includes a mechanical bottleneck 202, which is formed by a mechanical barrier 201, the mechanical barrier 201 preventing at least part of the air contaminated with ink mist 170 from being transported from the recording medium 120 into the dryer 150.
  • the bottleneck 202 is typically more effective the smaller the gap formed by the bottleneck 202 is and/or the higher the transport speed of the recording medium 120 is.
  • the gap of the bottleneck 202 typically cannot be made arbitrarily small in order to take into account tolerances, a certain waviness of the recording medium 120 and/or splices of the recording medium 120.
  • a counter-rotating rinsing air flow 204 can be generated, which is opposite to the direction of travel 1 of the recording medium 120.
  • the flushing air flow 204 can be generated by a blower 203, in particular by a so-called airknife.
  • An air flow 204 is generated, which flows into the constriction 202 in the opposite direction to the transport direction 1 and, if necessary, through the constriction 202. In this way, it can be reliably ensured that the boundary air layer on the recording medium 120, which has the ink mist 170, is prevented from flowing through the bottleneck 202.
  • the flushing air flow 204 can therefore cause leakage of ink mist 170 at the exit of the bottleneck 202 can be avoided.
  • the purging air flow 204 can cause the constriction 202 to appear narrower for the boundary air layer and thereby an increased proportion of the boundary air layer is stripped or separated at the constriction 202.
  • the effective efficiency of the bottleneck 202 can thus be increased.
  • the suction device 200 is thus designed to flow air or a gas through a constriction 202 in the opposite direction in order to “virtually” reduce the distance or the height of the constriction 202. In this way, the goal can be achieved to split off (ink) particles and/or aerosols entrained with the recording medium 120 above the recording medium 120 and to prevent further transport with the recording medium 120.
  • the bottleneck 202 and the purge air 204 can reduce the amount of ink mist 170 that is transported into the drying unit 150.
  • the ink mist 170 is sucked off by a suction unit 205 which is arranged in front of the bottleneck 202.
  • the suction unit 205 can be arranged in a flexible manner in spatial proximity or relatively far away from the bottleneck 202. A particularly efficient and comprehensive extraction in front of the bottleneck 202 can thus be made possible.
  • the constriction is preferably kept very short, i.e. is designed with a length of 0.1 mm to 10 mm and the mechanical barrier 201 breaks off against the transport direction 3 after the constriction 202, air turbulences and turbulences are downstream against the transport direction of the constriction generated, which cause the boundary air layer with the aerosols to detach from the recording medium and can therefore be better sucked out by the suction device 205.
  • Fig. 3 shows an alternative embodiment of a suction device 200.
  • the mechanical barrier 201 extends against the transport direction after the bottleneck 202 as a rounded ramp with increasing distance. In this way, the gas flow from the fan flows laminarly along the rounded shape after the narrow point
  • the mechanical barrier 201 extends in the transport direction from the bottleneck 202 as a rounded ramp with increasing distance.
  • a gas stream 204 is directed from the blower 203 to the bottleneck 202.
  • Fig. 4 shows a further alternative embodiment of a suction device 200.
  • the blower is set up to supply the gas flow to the constriction through an air duct 400 with a thickness between 0.1 mm and 1 mm, so that the gas flow 204 forms an air knife.
  • the mechanical barrier 204 extends from the narrow point 202 in the transport direction 3 as a ramp with a rounded shape with increasing distance from the recording medium 120.
  • the air duct 400 is here positively connected to one end of the ramp in the transport direction 3, so that the fan 203 causes a gas flow 204 laminar parallel to the ramp. This gas stream 204 along the rounded ramp forms a so-called “Coanda flow”.
  • Fig. 5 shows a flowchart of a method 300 for suctioning ink mist 170 in an inkjet printing device 100.
  • the printing device 100 comprises a printing unit 140 for printing on the front side of a recording medium 120 moved along a transport direction 1 through the printing unit 140.
  • the method 300 includes guiding 301 the recording medium 120 along the transport direction 1 through a constriction 202 arranged above the front of the recording medium 120.
  • the constriction 202 can have a height of 2-12 mm.
  • the bottleneck 202 can be designed to be connected to the recording medium 120 Limit the layer with ink mist 170 carried on the front of the recording medium 120 to a certain layer thickness by a mechanical and / or structural blockage.
  • the layer thickness can correspond to the height of the bottleneck 202.
  • the method 300 includes the effecting 302 of a gas stream 204, in particular an air stream, which runs in the constriction 202 counter to the transport direction 1 over the printed front side of the recording medium 120.
  • the gas flow 204 can be effected in a particularly efficient manner by a blower 203 arranged behind the narrow point 202 with respect to the transport direction 1.
  • the gas stream 204 can be designed to further reduce the effective layer thickness of the layer with ink mist 170 on the front side of the recording medium 120, in particular to reduce it by 50% or more or by 80% or more.
  • the method 300 further includes the suction 303 of ink mist 170 from the printed front of the recording medium 120 in a suction area which is arranged in front of the bottleneck 202 with respect to the transport direction 1.
  • the ink mist 170 can be sucked off by a suction unit 205, which is arranged in front of the bottleneck 202.
  • the combined use of a mechanical bottleneck 202 with a counter-rotating gas flow 204 within the bottleneck 202 enables efficient and comprehensive suction of the ink mist 170 in the suction area in front of the bottleneck 202.
  • the printing device 100 can, for example, in connection with Fig. 1a described, have a printing unit 140 for printing on the front of a recording medium 120 moved along a transport direction 1 through the printing unit 140.
  • the printing unit 140 can have one or more printing bars 102 and/or print heads 103, which are designed to apply drops of ink to the front of the recording medium 120.
  • ink mist 170 can be generated in the printing unit 140, which is entrained by the recording medium 120 moving in the transport direction 1 in an ink mist layer on the front of the recording medium 120.
  • the suction device 200 comprises a mechanical barrier 201, which is designed to form a structural constriction 202 over the front side of the recording medium 120, which is printed in the printing unit 140 and is guided past the mechanical barrier 201 in the transport direction 1.
  • the bottleneck 202 can be formed, for example, by a sheet metal which is arranged over the front of the recording medium 120 and which, if necessary, runs parallel to the front of the recording medium 120 along the transport direction 1.
  • the mechanical barrier 201 can form a ramp which extends away from the front of the recording medium 120 and along the transport direction 1. In this way, it can be reliably ensured that the part of the ink mist layer skimmed off through the bottleneck 202 is guided away from the recording medium 120. This makes particularly reliable suction of the ink mist 170 possible in a suction area in front of the bottleneck 202.
  • the mechanical barrier 201 can, for example, have a sheet metal which initially extends parallel to the recording medium 120 along the transport direction 1 in order to form the constriction 202, and which extends away from the recording medium 120 starting from the exit of the constriction 202 in order to form the constriction 202 to form a ramp.
  • the constriction 202 formed by the mechanical barrier 201 has a length of less than 25 mm, preferably less than 10 mm, even more preferably less than 5 mm, along the transport direction 1. 1 .
  • the bottleneck 202 can form a tunnel for the recording medium 120 running along the transport direction 1. The use of a bottleneck 202, which has a certain maximum spread along the transport direction 1, enables a particularly comprehensive blockage and suction of the ink mist 170.
  • the printing device 100 typically has a certain printing width transverse to the transport direction 1, over which the front of the recording medium 120 is printed in the printing unit 140.
  • the constriction 202 formed by the mechanical barrier 201 preferably extends over the entire printing width of the printing device 100. In this way, the ink mist 170 generated in the printing unit 140 can be blocked and sucked out in a particularly comprehensive manner.
  • the suction device 200 further comprises a blower 203, which is designed to cause a gas flow 204 running counter to the transport direction 1 in the constriction 202 above the printed front side of the recording medium 120.
  • the blower 203 in particular the so-called airknife/air knife, can be arranged at the exit of the bottleneck 202 with respect to the transport direction 1, and can be designed to cause a gas flow 204, in particular an air flow, which flows from the exit towards the entrance of the Bottleneck 202 runs.
  • the gas flow 204 caused by the blower 203 can be designed to be ink mist 170, which is entrained from the front of the recording medium 120 in the transport direction 1 from the entrance of the narrow point 202 towards the exit of the narrow point 202, back towards the entrance of the To push bottleneck 202. In this way, it can be reliably ensured that ink mist 170 is blocked on the mechanical barrier 201 and thus cannot reach a component 150 of the printing device 100 downstream of the suction device 200.
  • the gas flow 204 caused by the blower 203 can in particular be designed such that the ink mist 170 in the suction area in front of the bottleneck 202, in particular directly on the front of the recording medium 120, has a movement speed in the transport direction 1 which is smaller, in particular by a factor of 2 or more smaller than the transport speed of the recording medium 120.
  • the gas flow 204 can thus cause the ink mist layer on the front of the recording medium 120, in front of the entrance to the bottleneck 202, to be braked in order to reliably reduce the amount of ink mist 170 that passes through the bottleneck 202.
  • the gas flow 204 caused by the fan 203 can be designed to reduce the effective cross-sectional area of the constriction 202 perpendicular to the front of the recording medium 120, through which ink mist 170 can flow through the constriction 202, compared to the actual cross-sectional area of the constriction 202, in particular to reduce by 50% or more or by 80% or more.
  • the gas stream 204 thus makes it possible to use a relatively high constriction 202 in order to reliably prevent a collision between the recording medium 120 and the mechanical barrier 201 avoid, and still ensure reliable deposition of the ink mist 170.
  • the suction device 200 can be designed to ensure that a maximum of 10% of the ink mist 170 guided from the recording medium 120 to the entrance of the narrow point 202 emerges from the exit of the narrow point 202. This can be achieved in a reliable manner by the combination of a mechanical and/or structural bottleneck 202 and a counter-rotating gas flow 204.
  • the suction device 200 further comprises a suction unit 205, which is set up to suck ink mist 170 from the printed front side of the recording medium 120 in a suction area which is arranged in front of the bottleneck 202 with respect to the transport direction 1.
  • the suction unit 205 is arranged in front of the bottleneck 202.
  • the suction unit 205 preferably has a suction opening facing the front of the recording medium 120, which widens towards the front of the recording medium 120 and/or which tapers as the distance from the front of the recording medium 120 increases. In this way, a particularly efficient and comprehensive suction of the ink mist 170 can be effected in the suction area in front of the bottleneck 202.
  • a suction device 200 for an inkjet printing device 100 is thus described, which is designed to guide a printed recording medium 120 along a transport direction 1 through a mechanical bottleneck 202 with a counter-rotating gas flow 204 in order to efficiently and comprehensively ink mist 170 in the transport direction 1 to be able to vacuum in front of the bottleneck 202.
  • a printing device 100 is described in this document, which includes the suction device 200 described in this document.
  • the ink mist 170 generated in a printing unit 140 can be reliably eliminated, in particular in order to avoid contamination of downstream components such as a drying unit 150.

Landscapes

  • Ink Jet (AREA)

Description

Die Erfindung betrifft eine Vorrichtung und ein entsprechendes Verfahren zur Absaugung von Tintennebel.The invention relates to a device and a corresponding method for extracting ink mist.

Tintenstrahl-Druckvorrichtungen können zum Bedrucken von Aufzeichnungsträgern, wie z.B. Papier, eingesetzt werden. Dazu werden in einem Druckwerk der Druckvorrichtung ein oder mehrere Düsen verwendet, um Tintentropfen auf den Aufzeichnungsträger zu feuern und so ein gewünschtes Druckbild auf dem Aufzeichnungsträger zu erzeugen. Eine Tintenstrahl-Druckvorrichtung umfasst ferner typischerweise eine Trocknungseinheit, um den Aufzeichnungsträger nach Aufbringen des Druckbildes zu trocknen und um dadurch die aufgebrachte Tinte auf dem Aufzeichnungsträger zu fixieren.Inkjet printing devices can be used to print on recording media such as paper. For this purpose, one or more nozzles are used in a printing unit of the printing device to fire drops of ink onto the recording medium and thus produce a desired printed image on the recording medium. An inkjet printing device typically further comprises a drying unit in order to dry the recording medium after applying the printed image and thereby fixing the applied ink on the recording medium.

Beim Bedrucken des Aufzeichnungsträgers kann in dem Druckwerk ein Tintennebel, d.h. ein Aerosol mit Tintenpartikeln, entstehen, der von dem Aufzeichnungsträger in die Trocknungseinheit transportiert werden kann und der dort zu Verschmutzungen führen kann.When printing on the recording medium, an ink mist, i.e. an aerosol with ink particles, can arise in the printing unit, which can be transported from the recording medium into the drying unit and which can lead to contamination there.

JP 2010 - 284 892 A , JP 2010- 143 060 A , JP 2010- 201 874 A , US 2016/ 0 271 950 A1 , EP3081382 und JP2010284892 offenbaren eine Absaugvorrichtung für Tintennebel bei einem Tintenstrahldrucksystem, wobei die Absaugvorrichtung in Transportrichtung einer Engstelle nach dem Druckwerk nachgelagert ist. Nachteilig hierbei ist, dass zwischen dem Druckwerk und der Absaugvorrichtung Verschmutzungsmöglichkeiten für den Aufzeichnungsträger und das Drucksystem bestehen. JP 2010 - 284 892 A , JP 2010- 143 060 A , JP 2010- 201 874 A , US 2016/ 0 271 950 A1 , EP3081382 and JP2010284892 disclose a suction device for ink mist in an inkjet printing system, the suction device being downstream of a bottleneck after the printing unit in the transport direction. The disadvantage here is that there is a possibility of contamination for the recording medium and the printing system between the printing unit and the suction device.

US 2018/0001648 A1 offenbart eine Absaugvorrichtung für Tintennebel bei einem Tintenstrahldrucksystem, wobei die Absaugvorrichtung in Transportrichtung an derselben Position wie ein Gebläse angeordnet ist. US 2018/0001648 A1 discloses an ink mist suction device in an ink jet printing system, the suction device being arranged at the same position as a fan in the transport direction.

Das vorliegende Dokument befasst sich mit der technischen Aufgabe, durch Tintennebel bewirkte Verschmutzungen in effizienter und zuverlässiger Weise zu reduzieren oder zu vermeiden. Die Aufgabe wird jeweils durch die Merkmale des unabhängigen Vorrichtungsanspruchs 1 sowie durch die Merkmale des unabhängigen Verfahrensanspruchs 9 gelöst.This document deals with the technical task of reducing or avoiding contamination caused by ink mist in an efficient and reliable manner. The task is determined in each case by the characteristics of the independent Device claim 1 and solved by the features of the independent method claim 9.

Gemäß einem ersten Aspekt der Erfindung wird eine Absaugvorrichtung zur Absaugung von Tintennebel in einer Tintenstrahl-Druckvorrichtung beschrieben, wobei die Druckvorrichtung ein Druckwerk zum Bedrucken einer Vorderseite eines entlang einer Transportrichtung durch das Druckwerk bewegten, insbesondere bandförmigen, Aufzeichnungsträgers aufweist. Die Absaugvorrichtung umfasst eine mechanische Barriere, die ausgebildet ist, eine Engstelle über der in dem Druckwerk bedruckten Vorderseite des in Transportrichtung an der mechanischen Barriere vorbeigeführten Aufzeichnungsträgers zu bilden. Die Engstelle bildet einen Tunnel für den Aufzeichnungsträger und weist in Transportrichtung eine Erstreckung von weniger als 25 mm auf. Des Weiteren umfasst die Absaugvorrichtung ein Gebläse, das ausgebildet ist, in der Engstelle über der bedruckten Vorderseite des Aufzeichnungsträgers einen entgegen der Transportrichtung verlaufenden Gasstrom zu bewirken. Die Absaugvorrichtung umfasst ferner eine Absaugeinheit, die eingerichtet ist, in einem Absaugbereich, der in Bezug auf die Transportrichtung vor der Engstelle angeordnet ist, Tintennebel von der bedruckten Vorderseite des Aufzeichnungsträgers abzusaugen. Die Absaugvorrichtung kann zu diesem Zweck vor der Engstelle, insbesondere über dem Absaugbereich, angeordnet sein.According to a first aspect of the invention, a suction device for suctioning ink mist in an inkjet printing device is described, wherein the printing device has a printing unit for printing on a front side of a, in particular band-shaped, recording medium moved along a transport direction through the printing unit. The suction device comprises a mechanical barrier which is designed to form a constriction over the front side of the recording medium, which is printed in the printing unit and is guided past the mechanical barrier in the transport direction. The bottleneck forms a tunnel for the recording medium and has an extension of less than 25 mm in the transport direction. Furthermore, the suction device comprises a blower which is designed to cause a gas flow running counter to the transport direction in the narrow area above the printed front side of the recording medium. The suction device further comprises a suction unit which is set up to suck ink mist from the printed front side of the recording medium in a suction area which is arranged in front of the narrow point with respect to the transport direction. For this purpose, the suction device can be arranged in front of the bottleneck, in particular above the suction area.

Gemäß einem weiteren Aspekt wird ein Verfahren zur Absaugung von Tintennebel in einer Tintenstrahl-Druckvorrichtung beschrieben, wobei die Druckvorrichtung ein Druckwerk zum Bedrucken einer Vorderseite eines entlang einer Transportrichtung durch das Druckwerk bewegten Aufzeichnungsträgers aufweist. Das Verfahren umfasst das Führen des Aufzeichnungsträgers entlang der Transportrichtung durch eine über der Vorderseite des Aufzeichnungsträgers angeordneten mechanischen Engstelle. Das Verfahren umfasst ferner das Bewirken eines Gasstroms, der in der Engstelle entgegen der Transportrichtung über der bedruckten Vorderseite des Aufzeichnungsträgers verläuft. Außerdem umfasst das Verfahren das Absaugen von Tintennebel von der bedruckten Vorderseite des Aufzeichnungsträgers in einem Absaugbereich, der in Bezug auf die Transportrichtung vor der Engstelle angeordnet ist.According to a further aspect, a method for extracting ink mist in an inkjet printing device is described, wherein the printing device has a printing unit for printing on a front side of a recording medium moved along a transport direction through the printing unit. The method includes guiding the recording medium along the transport direction through a mechanical bottleneck arranged above the front of the recording medium. The method further comprises causing a gas flow to run in the narrow area opposite to the direction of transport over the printed front side of the recording medium. The method also includes suctioning off ink mist from the printed front side of the recording medium in a suction area which is arranged in front of the bottleneck with respect to the transport direction.

Dadurch, dass die Engstelle in Transportrichtung eine Erstreckung von weniger als 25 mm aufweist, kann durch den Gasstrom oder die Spülluft effektiv verhindert werden, dass Tintennebel in den Bereich der Engstelle eindringen kann.Because the bottleneck has an extension of less than 25 mm in the transport direction, the gas flow or the purging air can effectively prevent ink mist from penetrating the area of the bottleneck.

In einer besonders vorteilhaften Ausführungsform weist die Engstelle eine Erstreckung in Transportrichtung von weniger als 15 mm, bevorzugt weniger als 5 mm, noch bevorzugter von weniger als 2 mm auf. Dies ist vorteilhaft, da, je kleiner eine Erstreckung der Engstelle in Transportrichtung ausgebildet ist, desto effektiver kann ein Eindringen von Tintennebel aus einer Grenzluftschicht in der Nähe des Aufzeichnungsträgers in den Bereich der Engstelle verhindert werden.In a particularly advantageous embodiment, the constriction has an extension in the transport direction of less than 15 mm, preferably less than 5 mm, even more preferably less than 2 mm. This is advantageous because the smaller the extension of the constriction in the transport direction, the more effectively penetration of ink mist from a boundary air layer in the vicinity of the recording medium into the area of the constriction can be prevented.

Es ist dabei zweckmäßig, dass die mechanische Barriere sich in Transportrichtung von der Engstelle als Rampe mit zunehmendem Abstand zum Aufzeichnungsträger erstreckt, um einen Gasstrom des Gebläses entgegen der Transportrichtung zur Engstelle zu leiten. Dies stellt eine effektive Möglichkeit zur Verfügung, um den Tintennebel von der Engstelle fern zu halten.It is expedient that the mechanical barrier extends in the transport direction from the narrow point as a ramp with increasing distance to the recording medium in order to direct a gas flow from the fan against the transport direction to the narrow point. This provides an effective way to keep the ink mist away from the bottleneck.

Insbesondere bricht die mechanische Barriere entgegen der Transportrichtung nach der Engstelle ab, so dass der Gasstrom des Gebläses entgegen der Transportrichtung nach der Engstelle zu turbulenten Luftverwirbelungen führt, so dass Luft aus der Grenzluftschicht senkrecht zur Transportrichtung mitgerissen wird, wodurch sich die laminar strömende Grenzluftschicht von dem Aufzeichnungsträger ablöst. Auf diese Weise kann im Vergleich zum Stand der Technik ein wesentlich größerer Teil des Tintennebels zur Absaugeinrichtung geleitet und entfernt werden.In particular, the mechanical barrier breaks off against the transport direction after the narrow point, so that the gas flow of the blower against the transport direction after the narrow point leads to turbulent air turbulence, so that air from the boundary air layer is entrained perpendicular to the transport direction, as a result of which the laminar flowing boundary air layer is separated from the Record carrier replaced. In this way, compared to the prior art, a significantly larger portion of the ink mist can be directed to the suction device and removed.

Alternativ ist es denkbar, dass sich die mechanische Barriere entgegen der Transportrichtung nach der Engstelle rundlich als Rampe mit zunehmendem Abstand zum Aufzeichnungsträger erstreckt, so dass der Gasstrom des Gebläses nach der Engstelle laminar entlang der rundlichen Form mit zunehmendem senkrechten Abstand zum Aufzeichnungsträger entlangfließt und somit Luft aus der Grenzluftschicht senkrecht zur Transportrichtung mitgerissen wird und sich die laminar strömende Grenzluftschicht von dem Aufzeichnungsträger ablöst. Auch auf diese Weise kann im Vergleich zum Stand der Technik ein wesentlich größerer Teil des Tintennebels zur Absaugeinrichtung geleitet und entfernt werden.Alternatively, it is conceivable that the mechanical barrier extends against the transport direction after the narrow point in a round shape as a ramp with an increasing distance from the recording medium, so that the gas flow from the blower flows laminarly after the narrow point along the round shape with an increasing vertical distance from the recording medium and thus air is entrained from the boundary air layer perpendicular to the transport direction and the laminar flowing boundary air layer detaches itself from the recording medium. This can also be done in comparison to the prior art A significantly larger part of the ink mist is directed to the suction device and removed.

Bevorzugt erstreckt sich die mechanische Barriere von der Engstelle in Transportrichtung als Rampe mit einer rundlichen Form mit zunehmendem Abstand. Diese und andere Rampenformen erlauben eine effiziente Zufuhr des Gasstromes vom Gebläse zu der Engstelle.The mechanical barrier preferably extends from the narrow point in the transport direction as a ramp with a rounded shape with increasing distance. These and other ramp shapes allow an efficient supply of the gas flow from the fan to the bottleneck.

Insbesondere weist die Druckvorrichtung eine Druckbreite quer zu der Transportrichtung auf, über die die Vorderseite des Aufzeichnungsträgers in dem Druckwerk bedruckt wird. Noch zweckmäßiger ist es, wenn sich die Engstelle über die gesamte Druckbreite der Druckvorrichtung erstreckt. So kann beinahe der gesamte Tintennebel aus der Grenzluftschicht um den Aufzeichnungsträger entfernt werden.In particular, the printing device has a printing width transverse to the transport direction, over which the front side of the recording medium is printed in the printing unit. It is even more expedient if the bottleneck extends over the entire printing width of the printing device. In this way, almost all of the ink mist can be removed from the boundary air layer around the recording medium.

In einer vorteilhaften Ausführungsform ist der von dem Gebläse bewirkte Gasstrom derart ausgebildet, dass der Tintennebel in dem Absaugbereich, insbesondere direkt an der Vorderseite des Aufzeichnungsträgers, eine Bewegungsgeschwindigkeit in Transportrichtung aufweist, die kleiner, insbesondere um einen Faktor 2 oder mehr kleiner, als eine Transportgeschwindigkeit des Aufzeichnungsträgers ist. Erfahrungsgemäß kann auf diese Weise besonders viel Tintennebel aus der Grenzluftschicht entfernt werden.In an advantageous embodiment, the gas flow caused by the fan is designed such that the ink mist in the suction area, in particular directly on the front of the recording medium, has a movement speed in the transport direction that is smaller, in particular smaller by a factor of 2 or more, than a transport speed of the recording medium. Experience has shown that a particularly large amount of ink mist can be removed from the boundary air layer in this way.

Zweckmäßigerweise ist das Gebläse eingerichtet, den Gasstrom der Engstelle durch einen Luftkanal mit einer Dicke zwischen 0,1 mm und 1 mm zuzuführen, so dass der Gasstrom ein Luftmesser bildet. Der scharfe, schnelle und enge Gasstrom, der aus dem sehr engen Schlitz des Ausströmbereiches des "Luftmessers" kommt, bewegt sich nach der Gesetzmäßigkeit von Coanda um die Dicke des Luftmessers gegen die Transportrichtung des Aufzeichnungsträgers. Dabei wird auf der auslaufenden Seite der Engstelle zusätzlich viel Umgebungsluft aus der Grenzluftschicht in der Nähe des Aufzeichnungsträgers mitgerissen. Falls es dazu kommen kann, dass geringe Mengen des Aerosolnebels oder Tintennebels, der sich in der Grenzschicht der Bahn in Transportrichtung bewegt, doch durch die Engstelle kommen, so wird er sofort mit dem sich entgegen der Transportrichtung bewegenden Luftstrahl mitgenommen und wieder vor die Engstelle transportiert. Auf der einlaufenden Seite der Bahn kommen die Aerosole oder Tintennebeltropfen in der Grenzluftschicht mit dem bedruckten Medium an, können aber den Verschluss durch den Gasstrom in der Engstelle nicht passieren. Der Luftstrahl des Luftmessers bewegt sich in der Engstelle und danach entgegen der Transportrichtung je nach Ausbildung der mechanischen Barriere entweder laminar entlang einer Wand oder turbulent verwirbelnd derart, dass Luft oberhalb des Aufzeichnungsträgers nach oben mitgerissen wird. Bricht die mechanische Barriere entgegen der Transportrichtung nach der Engstelle ab, so ruft der Gasstrom nach der Engstelle turbulente Verwirbelungen hervor. Erstreckt sich die mechanische Barriere nach der Engstelle rundlich als Rampe mit zunehmendem Abstand, so fließt der Gasstrom des Gebläses nach der Engstelle laminar entlang der rundlichen Form Somit fließt dieser mit zunehmendem senkrechten Abstand zum Aufzeichnungsträger, so dass Luft aus der Grenzluftschicht senkrecht zur Transportrichtung mitgerissen wird.The blower is expediently set up to supply the gas flow to the constriction through an air duct with a thickness between 0.1 mm and 1 mm, so that the gas flow forms an air knife. The sharp, fast and narrow gas stream that comes from the very narrow slot of the outflow area of the "air knife" moves according to Coanda's law by the thickness of the air knife against the transport direction of the recording medium. A large amount of ambient air is also entrained from the boundary air layer near the recording medium on the outgoing side of the bottleneck. If it happens that small amounts of the aerosol mist or ink mist, which is moving in the boundary layer of the web in the transport direction, come through the narrow point, it will immediately be taken along with the air jet moving against the transport direction and transported back in front of the narrow point . On the incoming one On the side of the web, the aerosols or ink mist drops arrive in the boundary air layer with the printed medium, but cannot pass through the closure due to the gas flow in the bottleneck. The air jet from the air knife moves in the narrow area and then against the transport direction, depending on the design of the mechanical barrier, either laminarly along a wall or turbulently swirling in such a way that air above the recording medium is entrained upwards. If the mechanical barrier breaks off after the bottleneck in the opposite direction to the transport direction, the gas flow after the bottleneck causes turbulent turbulence. If the mechanical barrier extends in a round shape after the bottleneck as a ramp with increasing distance, the gas flow from the blower flows laminarly along the rounded shape after the bottleneck. This flows with increasing vertical distance to the recording medium, so that air is entrained from the boundary air layer perpendicular to the transport direction .

Der scharfe, schnelle und enge Gasstrom, der aus dem sehr engen Luftkanal des "Luftmessers" kommt, bewegt sich nach der Gesetzmäßigkeit von Coanda gegen die Transportrichtung. Dabei wird von einer Position, die dem Luftkanal in Transportrichtung nachgelagert ist, zusätzlich Umgebungsluft mitgerissen. Falls geringe Mengen des Aerosolnebels aus der Grenzluftschicht in die Engstelle gelangen, so wird dieser Aerosolnebel unmittelbar mit dem entgegen der Transportrichtung fließenden Luftstrahl mitgenommen und wieder vor die Engstelle transportiert.The sharp, fast and narrow gas stream coming from the very narrow air channel of the "air knife" moves against the direction of transport according to Coanda's law. Additional ambient air is entrained from a position downstream of the air duct in the transport direction. If small amounts of the aerosol mist reach the constriction from the boundary air layer, this aerosol mist is immediately carried along with the air jet flowing against the transport direction and transported again in front of the constriction.

Somit wird die aerosolhaltige Luft hervorragend von der Grenzluftschicht am Aufzeichnungsträger abgehoben und mit der Strahlluft weg von dem Aufzeichnungsträger transportiert.The aerosol-containing air is thus excellently lifted off the boundary air layer on the recording medium and transported away from the recording medium with the jet air.

Eine geeignete Absaugvorrichtung kann die aerosolhaltige Luft aufnehmen und einer geeigneten Entsorgung zuführen.A suitable suction device can absorb the aerosol-containing air and dispose of it appropriately.

Bevorzugt beträgt die Spalthöhe zwischen dem Aufzeichnungsträger und eine Auslassstelle des Luftkanals zwischen 0 und 25 mm, bevorzugter zwischen 1 und 10 mm, noch bevorzugter zwischen 1 und 5 mm. Auf diese Weise kann eine besonders effiziente Wirkung auf die Grenzluftschicht am Aufzeichnungsträger erzielt werden.The gap height between the recording medium and an outlet point of the air duct is preferably between 0 and 25 mm, more preferably between 1 and 10 mm, even more preferably between 1 and 5 mm. In this way, a particularly efficient effect on the boundary air layer on the recording medium can be achieved.

Insbesondere bildet der Luftkanal einen Winkel zwischen 10° und 80°, bevorzugt zwischen 20° und 70°, noch bevorzugter zwischen 30° und 60° zur Transportrichtung. Ein Winkel von 45° hat sich als besonders zweckmäßig erwiesen.In particular, the air duct forms an angle between 10° and 80°, preferably between 20° and 70°, even more preferably between 30° and 60° to the transport direction. An angle of 45° has proven to be particularly useful.

Im Weiteren werden Ausführungsbeispiele der Erfindung anhand der schematischen Zeichnung näher beschrieben. Dabei zeigen:

Fig. 1a
ein Blockdiagramm einer beispielhaften Tintenstrahl-Druckvorrichtung mit einer Trocknungs- bzw. Fixiereinheit;
Fig. 1b
ein Blockdiagramm einer beispielhaften Trocknungseinheit für eine Tintenstrahl-Druckvorrichtung;
Fig. 1c
eine beispielhafte Tintenstrahl-Druckvorrichtung in einer Seitenansicht;
Fig. 2
eine beispielhafte Absaugvorrichtung für eine Tintenstrahl-Druckvorrichtung;
Fig. 3
eine alternative beispielhafte Absaugvorrichtung für eine Tintenstrahl-Druckvorrichtung;
Fig. 4
eine weitere alternative beispielhafte Absaugvorrichtung für eine Tintenstrahl-Druckvorrichtung; und
Fig. 5
ein Ablaufdiagramm eines beispielhaften Verfahrens zur Absaugung von Tintennebel in einer Tintenstrahl-Druckvorrichtung.
In the following, exemplary embodiments of the invention are described in more detail with reference to the schematic drawing. Show:
Fig. 1a
a block diagram of an exemplary inkjet printing device with a drying or fixing unit;
Fig. 1b
a block diagram of an exemplary drying unit for an inkjet printing device;
Fig. 1c
an exemplary inkjet printing device in a side view;
Fig. 2
an exemplary suction device for an inkjet printing device;
Fig. 3
an alternative exemplary suction device for an inkjet printing device;
Fig. 4
another alternative exemplary suction device for an inkjet printing device; and
Fig. 5
a flowchart of an exemplary method for extracting ink mist in an inkjet printing device.

Die in Fig. 1a dargestellte Druckvorrichtung 100 ist für den Druck auf einen bogen- oder blatt- oder plattenförmigen oder bandförmigen Aufzeichnungsträger 120 ausgelegt. Der Aufzeichnungsträger 120 kann aus Papier, Pappe, Karton, Metall, Kunststoff, Textilien, einer Kombination davon und/oder sonstigen geeigneten und bedruckbaren Materialien hergestellt sein. Der Auszeichnungsträger 120 wird entlang der Transportrichtung 1, dargestellt durch einen Pfeil, durch das Druckwerk 140 der Druckvorrichtung 100 geführt.In the Fig. 1a The printing device 100 shown is designed for printing on a sheet-shaped or sheet-shaped or plate-shaped or tape-shaped recording medium 120. The recording medium 120 can be made of paper, cardboard, cardboard, metal, plastic, textiles, a combination thereof and/or other suitable and printable materials. The award holder 120 is guided through the printing unit 140 of the printing device 100 along the transport direction 1, shown by an arrow.

Das Druckwerk 140 der Druckvorrichtung 100 umfasst in dem dargestellten Beispiel zwei Druckriegel 102, wobei jeder Druckriegel 102 für das Drucken mit Tinte einer bestimmten Farbe verwendet werden kann, z.B. Schwarz, Cyan, Magenta und/oder Gelb und ggf. MICR-Tinte. Unterschiedliche Druckriegel 102 können für das Drucken mit jeweils unterschiedlichen Tinten verwendet werden. Des Weiteren umfasst die Druckvorrichtung 100 zumindest eine Fixier- bzw. Trocknungseinheit 150, die eingerichtet ist, ein auf den Aufzeichnungsträger 120 gedrucktes Druckbild zu fixieren.In the example shown, the printing unit 140 of the printing device 100 includes two printing bars 102, whereby each printing bar 102 can be used for printing with ink of a specific color, for example black, cyan, magenta and/or yellow and possibly MICR ink. Different printing bars 102 can be used for printing with different inks. Furthermore, the printing device 100 includes at least one fixing or drying unit 150, which is set up to fix a printed image printed on the recording medium 120.

Ein Druckriegel 102 kann ein oder mehrere Druckköpfe 103 umfassen, die ggf. in mehreren Reihen nebeneinander angeordnet sind, um die Bildpunkte unterschiedlicher Spalten 31, 32 eines Druckbildes auf den Aufzeichnungsträger 120 zu drucken. In dem in Fig. 1a dargestellten Beispiel umfasst ein Druckriegel 102 fünf Druckköpfe 103, wobei jeder Druckkopf 103 die Bildpunkte einer Gruppe von Spalten 31, 32 eines Druckbildes auf den Aufzeichnungsträger 120 druckt.A printing bar 102 can comprise one or more print heads 103, which may be arranged next to one another in several rows in order to print the pixels of different columns 31, 32 of a printed image onto the recording medium 120. In the in Fig. 1a In the example shown, a print bar 102 comprises five print heads 103, each print head 103 printing the pixels of a group of columns 31, 32 of a print image onto the recording medium 120.

Jeder Druckkopf 103 des Druckwerks 140 umfasst in der in Fig. 1a abgebildeten Ausführungsform mehrere Düsen 21, 22, wobei jede Düse 21, 22 eingerichtet ist, Tintentropfen auf den Aufzeichnungsträger 120 zu feuern oder zu stoßen. Ein Druckkopf 103 des Druckwerks 140 kann beispielsweise mehrere Tausend effektiv genutzte Düsen 21, 22 umfassen, die entlang mehrerer Reihen quer zur Transportrichtung 1, d.h. entlang der Druckbreite, des Aufzeichnungsträgers 120 angeordnet sind. Mittels der Düsen 21, 22 eines Druckkopfs 103 des Druckwerks 140 können Bildpunkte einer Zeile eines Druckbildes auf den Aufzeichnungsträger 120 quer zur Transportrichtung 1, d.h. entlang der Breite des Aufzeichnungsträgers 120, gedruckt werden.Each print head 103 of the printing unit 140 includes in the Fig. 1a illustrated embodiment several nozzles 21, 22, each nozzle 21, 22 being set up to fire or push ink drops onto the recording medium 120. A print head 103 of the printing unit 140 can, for example, comprise several thousand effectively used nozzles 21, 22, which are arranged along several rows transversely to the transport direction 1, ie along the printing width, of the recording medium 120. By means of the nozzles 21, 22 of a print head 103 of the printing unit 140, pixels of a line of a printed image can be printed onto the recording medium 120 transversely to the transport direction 1, ie along the width of the recording medium 120.

Die Druckvorrichtung 100 umfasst ferner eine Steuereinheit 101, z.B. eine Ansteuer-Hardware und/oder einen Controller, die eingerichtet ist, die Aktuatoren der einzelnen Düsen 21, 22 der einzelnen Druckköpfe 103 des Druckwerks 140 anzusteuern, um in Abhängigkeit von Druckdaten das Druckbild auf den Aufzeichnungsträger 120 aufzubringen. Die Druckdaten können für jede Düse 21, 22, d.h. für jede Spalte 31, 32 des Druckbildes, und für jede Zeile des Druckbildes jeweils anzeigen, ob ein Tintenausstoß erfolgen soll oder nicht, und ggf. welche Tintenmenge ausgestoßen werden soll.The printing device 100 further comprises a control unit 101, for example a control hardware and/or a controller, which is set up to control the actuators of the individual nozzles 21, 22 of the individual print heads 103 of the printing unit 140 in order to print the printed image depending on print data Apply recording medium 120. The print data can indicate for each nozzle 21, 22, i.e. for each column 31, 32 of the print image, and for each line of the print image, whether or not ink should be ejected and, if applicable, what amount of ink should be ejected.

Das Druckwerk 140 der Druckvorrichtung 100 umfasst somit zumindest einen Druckriegel 102 mit K Düsen 21, 22, die mit einem bestimmten Zeilentakt angesteuert werden können, um eine Zeile, die quer zu der Transportrichtung 1 des Aufzeichnungsträgers 120 verläuft, mit K Pixeln bzw. K Spalten 31, 32 eines Druckbildes auf den Aufzeichnungsträger 120 zu drucken, z.B. mit K>1000. Die Düsen 21, 22 sind in dem dargestellten Beispiel unbeweglich bzw. fest in der Druckvorrichtung 100 verbaut, und der Aufzeichnungsträger 120 wird mit einer bestimmten Transportgeschwindigkeit an den feststehenden Düsen 21, 22 vorbeigeführt.The printing unit 140 of the printing device 100 thus comprises at least one printing bar 102 with K nozzles 21, 22, which can be controlled with a specific line cycle in order to create a line that runs transversely to the transport direction 1 of the recording medium 120, with K pixels or K columns 31, 32 to print a print image onto the recording medium 120, for example with K>1000. In the example shown, the nozzles 21, 22 are immovably or permanently installed in the printing device 100, and the recording medium 120 is guided past the fixed nozzles 21, 22 at a certain transport speed.

Wie oben dargelegt, kann die Druckvorrichtung 100 eine Trocknungseinheit 150 umfassen, die eingerichtet ist, den Aufzeichnungsträger 120 nach Aufbringen der Tinte durch die ein oder mehreren Druckriegel 102 zu trocknen und damit das aufgebrachte Druckbild auf dem Aufzeichnungsträger 120 zu fixieren. Die in Fig. 1b dargestellte Trocknungseinheit 150 umfasst mehrere Trocknungsmodule 160, die entlang einer Trocknungsstrecke an beiden Seiten des, typischerweise bahnförmigen, Aufzeichnungsträgers 120 angeordnet sind, und die jeweils eingerichtet sind, ein gasförmiges Trocknungsmedium, typischerweise erwärmte Luft, auf die Oberfläche des Aufzeichnungsträgers 120 zu blasen. Die Trocknungsstrecke mit den Trocknungsmodulen 160 ist dabei in einem Gehäuse 155 der Trocknungseinheit 150 angeordnet. Durch das Anblasen mit einem gasförmigen Trocknungsmedium kann das Druckbild auf einem Aufzeichnungsträger 120 in schonender und zuverlässiger Weise entlang der Trocknungsstrecke der Trocknungseinheit 150 getrocknet werden.As explained above, the printing device 100 can include a drying unit 150, which is set up to dry the recording medium 120 after the ink has been applied by the one or more printing bars 102 and thus to fix the applied printed image on the recording medium 120. In the Fig. 1b Drying unit 150 shown comprises a plurality of drying modules 160, which are arranged along a drying path on both sides of the, typically web-shaped, recording medium 120, and which are each set up to blow a gaseous drying medium, typically heated air, onto the surface of the recording medium 120. The drying section with the drying modules 160 is arranged in a housing 155 of the drying unit 150. By blowing with a gaseous drying medium, the printed image on a recording medium 120 can be dried in a gentle and reliable manner along the drying section of the drying unit 150.

Während des Druckbetriebs entsteht in dem Druckwerk 140 typischerweise ein Tintennebel, der Farbpigmente der ein oder mehreren unterschiedlichen Tinten umfasst, mit denen in dem Druckwerk 140 gedruckt wird. Der Tintennebel 170 kann, wie beispielhaft in Fig. 1c dargestellt, von dem Aufzeichnungsträger 120 entlang der Transportrichtung 1 mitgerissen werden. Insbesondere kann der Tintennebel 170 von dem Druckwerk 140 in die nachfolgende Trocknungseinheit 150 transportiert werden. Der Tintennebel 170 kann dann zu Verunreinigungen in dem Gehäuse 155, insbesondere an den ein oder mehreren Trocknungsmodulen 160, der Trocknungseinheit 150 führen, wobei durch die Verunreinigungen die Güte der Trocknung des Aufzeichnungsträgers 120 beeinträchtigt werden kann.During printing operation, an ink mist typically arises in the printing unit 140, which includes color pigments of the one or more different inks with which printing is carried out in the printing unit 140. The ink mist 170 can, as exemplified in Fig. 1c shown, are carried along by the recording medium 120 along the transport direction 1. In particular, the ink mist 170 can be transported from the printing unit 140 into the subsequent drying unit 150. The ink mist 170 can then lead to contamination in the housing 155, in particular on the one or more drying modules 160, of the drying unit 150, whereby the quality of the drying of the recording medium 120 can be impaired by the contamination.

Fig. 2 zeigt eine beispielhafte Absaugvorrichtung 200, die in Bezug auf die Transportrichtung 3 hinter dem Druckwerk 140 und/oder vor der Trocknungseinheit 150 angeordnet ist. Die Absaugvorrichtung 200 umfasst eine mechanische Barriere 201, die eine mechanische Engstelle 202 bildet, durch die der Aufzeichnungsträger 120 durchgeführt wird. Die Engstelle 202 kann eine Höhe senkrecht zu der Oberfläche, insbesondere senkrecht zu der Vorderseite, des Aufzeichnungsträgers 120 aufweisen, die einerseits möglichst klein ist, um nur einen möglichst kleinen Anteil des mit dem Aufzeichnungsträger 120 mitgerissenen Tintennebels 170 durchzulassen, die aber andererseits ausreichend groß ist, um Kollisionen mit dem Aufzeichnungsträger 120 zu vermeiden. Die Engstelle 202 kann z.B. eine Höhe zwischen 1 und 12 mm, bevorzugt zwischen 1 und 3 mm, aufweisen. Fig. 2 shows an exemplary suction device 200, which is arranged behind the printing unit 140 and/or in front of the drying unit 150 with respect to the transport direction 3. The suction device 200 comprises a mechanical barrier 201, which forms a mechanical bottleneck 202 through which the recording medium 120 is passed. The constriction 202 can have a height perpendicular to the surface, in particular perpendicular to the front, of the recording medium 120, which on the one hand is as small as possible in order to allow only the smallest possible proportion of the ink mist 170 entrained with the recording medium 120 to pass through, but which on the other hand is sufficiently large to avoid collisions with the To avoid recording medium 120. The constriction 202 can, for example, have a height between 1 and 12 mm, preferably between 1 and 3 mm.

Des Weiteren weist die Engstelle 202 eine bestimmte Länge in Transportrichtung 1 auf, so dass die Engstelle 202 einen Tunnel für den Aufzeichnungsträger 120 bildet. Die Engstelle 202 weist erfindungsgemäß eine Länge auf, die deutlich unter 25 mm ist. Insbesondere ist es vorteilhaft, wenn die Länge kleiner als 15, noch bevorzugter kleiner als 10 mm, insbesondere kleiner als 5 mm beträgt. Durch die Bereitstellung einer Engstelle 202, die eine bestimmte Höchstlänge in Transportrichtung 1 aufweist, wird eine turbulente Luftverwirbelung oder ein laminarer Strömungsabriss von der Grenzluftschicht erzeugt.Bevorzugt erstreckt sich die mechanische Barriere 201 in Transportrichtung von der Engstelle 202 als Rampe mit zunehmendem Abstand. So wird ein Gasstrom 204 von dem Gebläse 203 zur Engstelle 202 geleitet.. Die mechanische Barriere 201 bricht in dieser Ausführungsform nach der Engstelle 202 ab, so dass der Gasstrom 204 des Gebläses 203 entgegen der Transportrichtung 3 nach der Engstelle zu turbulenten Luftverwirbelungen führt. Auf diese Weise wird Luft aus der Grenzluftschicht senkrecht zur Transportrichtung mitgerissen, wodurch sich die laminar strömende Grenzluftschicht von dem Aufzeichnungsträger 120 ablöst.Furthermore, the bottleneck 202 has a certain length in the transport direction 1, so that the bottleneck 202 forms a tunnel for the recording medium 120. According to the invention, the bottleneck 202 has a length that is significantly less than 25 mm. In particular, it is advantageous if the length is less than 15, more preferably less than 10 mm, in particular less than 5 mm. By providing a bottleneck 202, which has a certain maximum length in the transport direction 1, a turbulent air turbulence or a laminar flow separation from the boundary air layer is generated. The mechanical barrier 201 preferably extends in the transport direction from the bottleneck 202 as a ramp with increasing distance. A gas stream 204 is directed from the fan 203 to the constriction 202. In this embodiment, the mechanical barrier 201 breaks off after the constriction 202, so that the gas flow 204 of the fan 203 leads to turbulent air turbulences after the constriction against the transport direction 3. In this way, air is entrained from the boundary air layer perpendicular to the transport direction, as a result of which the laminar-flowing boundary air layer detaches from the recording medium 120.

Die Absaugvorrichtung 200 umfasst ferner ein Gebläse 203, das ausgebildet ist, einen Gasstrom 204 an dem Ausgang der Engstelle 202 zu bewirken, der gegenläufig zu der Transportrichtung 1 ist. Der Gasstrom 204 wird in diesem Dokument auch als Blockade-Gasstrom 204 bezeichnet, da der Gasstrom 204 darauf ausgelegt ist, den von dem Aufzeichnungsträger 120 mitgerissenen Tintennebel 170 in einer Grenzluftschicht an der Engstelle 202 zu blockieren und diese Grenzluftschicht inklusive Tintennebel 170 senkrecht von der Transportrichtung abzulösen. Das Gebläse 203 kann hinter der Engstelle 202, insbesondere hinter dem Ausgang der Engstelle 202, angeordnet sein. Dabei verläuft das Gebläse 203 quer zur Transportrichtung des Substrats und überdeckt mindestens die Breite des Substrats.The suction device 200 further comprises a blower 203, which is designed to cause a gas flow 204 at the exit of the bottleneck 202, which is opposite to the transport direction 1. The gas stream 204 is also referred to in this document as a blocking gas stream 204, since the gas stream 204 is designed to block the ink mist 170 entrained by the recording medium 120 in a boundary air layer at the bottleneck 202 and this boundary air layer including the ink mist 170 perpendicular to the transport direction to replace. The blower 203 can be arranged behind the bottleneck 202, in particular behind the exit of the bottleneck 202. The fan 203 runs transversely to the transport direction of the substrate and covers at least the width of the substrate.

Des Weiteren umfasst die Absaugvorrichtung 200 eine Absaugeinheit 205, die eingerichtet ist, den Tintennebel 170 vor der Engstelle 202 abzusaugen. Die Absaugeinheit 205 kann vor der Engstelle 202, insbesondere vor dem Eingang der Engstelle 202, angeordnet sein. Ferner kann die Absaugeinheit 205 separat von der mechanischen Barriere 201 zur Bildung der Engstelle 202 sein. Durch den Blockade-Gasstrom 204 wird bewirkt, dass der Tintennebel 170 am Eingang der Engstelle 202 und/oder vor der Engstelle 202 sich mit einer Luftbewegung des Blockade-Gasstromes 204 senkrecht zur Transportrichtung abzulöst, so dass der Tintennebel 170 in effizienter Weise durch eine vor der Engstelle 202 angeordnete Absaugeinheit 205 abgesaugt werden kann. Dies kann auch durch einen relativ kleinen Ansaug-Volumenstrom und/oder durch eine relativ kleine Ansaugleistung bewirkt werden. Die Ansaugeinheit 205 kann dabei eine relativ große Absaugöffnung, ähnlich einer Dunstabzugshaube, aufweisen, um den Tintennebel 170 großflächig abzusaugen.Furthermore, the suction device 200 includes a suction unit 205, which is set up to suck out the ink mist 170 in front of the bottleneck 202. The suction unit 205 can be arranged in front of the bottleneck 202, in particular in front of the entrance to the bottleneck 202. Furthermore, the suction unit 205 can be separate from the mechanical barrier 201 to form the Be bottleneck 202. The blocking gas stream 204 causes the ink mist 170 at the entrance to the constriction 202 and/or in front of the constriction 202 to detach itself with an air movement of the blocking gas stream 204 perpendicular to the transport direction, so that the ink mist 170 is efficiently transported through a forward The suction unit 205 arranged in the constriction 202 can be sucked out. This can also be achieved by a relatively small intake volume flow and/or by a relatively low intake power. The suction unit 205 can have a relatively large suction opening, similar to an extractor hood, in order to suck out the ink mist 170 over a large area.

Durch die in Fig. 2 dargestellte Absaugvorrichtung 200 kann in zuverlässiger Weise vermieden werden, dass der Tintennebel 170 die nachfolgende Trocknungseinheit 150 verunreinigt.Through the in Fig. 2 The suction device 200 shown can be reliably prevented from causing the ink mist 170 to contaminate the subsequent drying unit 150.

Es wird somit eine zwischen den ein oder mehreren Druckköpfen 103 und der Fixierung 150 angeordnete Tintennebelabsaugung 200 beschrieben. Die Absaugung 200 umfasst eine mechanische Engstelle 202, die durch eine mechanische Barriere 201 gebildet wird, wobei die mechanische Barriere 201 zumindest einen Teil der mit Tintennebel 170 verschmutzten Luft daran hindert, von dem Aufzeichnungsträger 120 in den Trockner 150 transportiert zu werden. Die Engstelle 202 ist typischerweise umso effektiver, je kleiner der durch die Engstelle 202 gebildete Spalt ist, und/oder umso höher die Transportgeschwindigkeit des Aufzeichnungsträgers 120 ist. Dabei kann der Spalt der Engstelle 202 typischerweise nicht beliebig klein gemacht werden, um Toleranzen, eine bestimmte Welligkeit des Aufzeichnungsträgers 120 und/oder Klebestellen des Aufzeichnungsträgers 120 zu berücksichtigen.An ink mist suction 200 arranged between the one or more print heads 103 and the fixation 150 is thus described. The suction 200 includes a mechanical bottleneck 202, which is formed by a mechanical barrier 201, the mechanical barrier 201 preventing at least part of the air contaminated with ink mist 170 from being transported from the recording medium 120 into the dryer 150. The bottleneck 202 is typically more effective the smaller the gap formed by the bottleneck 202 is and/or the higher the transport speed of the recording medium 120 is. The gap of the bottleneck 202 typically cannot be made arbitrarily small in order to take into account tolerances, a certain waviness of the recording medium 120 and/or splices of the recording medium 120.

Zur weiteren Erhöhung des Wirkungsgrads kann ein gegenläufiger Spül-Luftstrom 204 generiert werden, der gegenläufig zu der Laufrichtung 1 des Aufzeichnungsträgers 120 ist. Der Spül-Luftstrom 204 kann durch ein Gebläse 203, insbesondere durch ein sogenanntes Airknife, erzeugt werden. Es wird dabei ein Luftstrom 204 erzeugt, der gegenläufig zu der Transportrichtung 1 in die Engstelle 202 hinein und ggf. durch die Engstelle 202 hindurch strömt. So kann in zuverlässiger Weise bewirkt werden, dass die Grenzluftschicht an dem Aufzeichnungsträger 120, die den Tintennebel 170 aufweist, daran gehindert wird, durch die Engstelle 202 hindurch zu strömen. Durch den Spül-Luftstrom 204 kann somit ein Austreten von Tintennebel 170 am Ausgang der Engstelle 202 vermieden werden. Insbesondere kann durch den Spül-Luftstrom 204 bewirkt werden, dass die Engstelle 202 für die Grenzluftschicht enger erscheint und dadurch ein erhöhter Anteil der Grenzluftschicht an der Engstelle 202 abgestreift bzw. abgesondert wird. Somit kann der effektive Wirkungsgrad der Engstelle 202 erhöht werden.To further increase the efficiency, a counter-rotating rinsing air flow 204 can be generated, which is opposite to the direction of travel 1 of the recording medium 120. The flushing air flow 204 can be generated by a blower 203, in particular by a so-called airknife. An air flow 204 is generated, which flows into the constriction 202 in the opposite direction to the transport direction 1 and, if necessary, through the constriction 202. In this way, it can be reliably ensured that the boundary air layer on the recording medium 120, which has the ink mist 170, is prevented from flowing through the bottleneck 202. The flushing air flow 204 can therefore cause leakage of ink mist 170 at the exit of the bottleneck 202 can be avoided. In particular, the purging air flow 204 can cause the constriction 202 to appear narrower for the boundary air layer and thereby an increased proportion of the boundary air layer is stripped or separated at the constriction 202. The effective efficiency of the bottleneck 202 can thus be increased.

Die Absaugvorrichtung 200 ist somit ausgebildet, eine Engstelle 202 in gegenläufiger Richtung mit Luft oder einem Gas zu durchströmen, um damit "virtuell" den Abstand bzw. die Höhe der Engstelle 202 zu verringern. So kann das Ziel erreicht werden, mit dem Aufzeichnungsträger 120 mitgerissene (Tinten-) Partikel und/oder Aerosole über dem Aufzeichnungsträger 120 abzuspalten und den Weitertransport mit dem Aufzeichnungsträger 120 zu verhindern.The suction device 200 is thus designed to flow air or a gas through a constriction 202 in the opposite direction in order to “virtually” reduce the distance or the height of the constriction 202. In this way, the goal can be achieved to split off (ink) particles and/or aerosols entrained with the recording medium 120 above the recording medium 120 and to prevent further transport with the recording medium 120.

Durch die Engstelle 202 und durch die Spülluft 204 kann die Menge an Tintennebel 170 reduziert werden, die in die Trocknungseinheit 150 transportiert wird. Um Verschmutzungen der Druckvorrichtung 100 und/oder der Umgebung der Druckvorrichtung 100 durch Aerosole zu vermeiden, wird der Tintennebel 170 durch eine Absaugeinheit 205, die vor der Engstelle 202 angeordnet ist, abgesaugt. Die Absaugeinheit 205 kann dabei in flexibler Weise in räumlicher Nähe oder auch relativ weit weg von der Engstelle 202 angeordnet sein. Es kann somit eine besonders effiziente und umfassende Absaugung vor der Engstelle 202 ermöglicht werden.The bottleneck 202 and the purge air 204 can reduce the amount of ink mist 170 that is transported into the drying unit 150. In order to avoid contamination of the printing device 100 and/or the surroundings of the printing device 100 by aerosols, the ink mist 170 is sucked off by a suction unit 205 which is arranged in front of the bottleneck 202. The suction unit 205 can be arranged in a flexible manner in spatial proximity or relatively far away from the bottleneck 202. A particularly efficient and comprehensive extraction in front of the bottleneck 202 can thus be made possible.

Dadurch, dass die Engstelle bevorzugt sehr kurz gehalten ist, d.h. mit einer Länge von 0,1 mm bis 10 mm ausgebildet ist und die mechanische Barriere 201 entgegen der Transportrichtung 3 nach der Engstelle 202 abbricht, werden entgegen der Transportrichtung der Engstelle nachgelagert Luftverwirbelungen und Turbulenzen erzeugt, die dazu führen, dass sich die Grenzluftschicht mit den Aerosolen von dem Aufzeichnungsträger ablöst und somit besser von der Absaugeinrichtung 205 abgesaugt werden kann.Because the constriction is preferably kept very short, i.e. is designed with a length of 0.1 mm to 10 mm and the mechanical barrier 201 breaks off against the transport direction 3 after the constriction 202, air turbulences and turbulences are downstream against the transport direction of the constriction generated, which cause the boundary air layer with the aerosols to detach from the recording medium and can therefore be better sucked out by the suction device 205.

Fig. 3 zeigt eine alternative Ausführungsform einer Absaugeinrichtung 200. Hierbei erstreckt sich die mechanische Barriere 201 entgegen der Transportrichtung nach der Engstelle 202 als rundliche Rampe mit zunehmendem Abstand. Auf diese Weise fließt der Gasstrom des Gebläses nach der Engstelle laminar entlang der rundlichen Form mit zunehmendem Fig. 3 shows an alternative embodiment of a suction device 200. Here, the mechanical barrier 201 extends against the transport direction after the bottleneck 202 as a rounded ramp with increasing distance. In this way, the gas flow from the fan flows laminarly along the rounded shape after the narrow point

Abstand.vom Aufzeichnungsträger 120. Auch hier wird Luft aus der Grenzluftschicht senkrecht zur Transportrichtung 3 mitgerissen, so dass sich die laminar strömende Grenzluftschicht vom Aufzeichnungsträger 120 löst. Weiterhin erstreckt sich die mechanische Barriere 201 in Transportrichtung von der Engstelle 202 als rundliche Rampe mit zunehmendem Abstand. So wird ein Gasstrom 204 von dem Gebläse 203 zur Engstelle 202 geleitet..Distance from the recording medium 120. Here too, air is entrained from the boundary air layer perpendicular to the transport direction 3, so that the laminar-flowing boundary air layer detaches from the recording medium 120. Furthermore, the mechanical barrier 201 extends in the transport direction from the bottleneck 202 as a rounded ramp with increasing distance. A gas stream 204 is directed from the blower 203 to the bottleneck 202.

Fig. 4 zeigt eine weitere alternative Ausführungsform einer Absaugeinrichtung 200. Das Gebläse ist in diesem Fall eingerichtet, den Gasstrom der Engstelle durch einen Luftkanal 400 mit einer Dicke zwischen 0,1 mm und 1 mm zuzuführen, so dass der Gasstrom 204 ein Luftmesser bildet. In dieser Ausführungsform erstreckt sich die mechanische Barriere 204 von der Engstelle 202 in Transportrichtung 3 als Rampe mit einer rundlichen Form mit zunehmendem Abstand zum Aufzeichnungsträger 120. Der Luftkanal 400 ist hier formschlüssig mit einem Ende der Rampe in Transportrichtung 3 verbunden, so dass das Gebläse 203 einen Gasstrom 204 laminar parallel zur Rampe bewirkt. Dieser Gasstrom 204 entlang der rundlichen Rampe bildet eine sog. "Coanda-Strömung" aus. Diese besteht aus einer Grenzschicht, einer relativ dünnen ungestörten Luftschicht, dem Strahl, der die Rampe entlang strömt, dann aus einer weiteren Reibungsschicht zu den Luftmassen außerhalb des Coanda-Strahls. Die Luft außen ist in Ruhe, weshalb es keinen Druckanstieg gemäß Bernulli-Gesetz gibt. Deshalb haftet die Coanda.-Strömung länger als eine normale Strömung an der Rampe, an der sie entlangfließt. Auf diese Weise wird die Grenzluftschicht am Aufzeichnungsträger 120 senkrecht zur Transportrichtung 3 mitgerissen und kann abgesaugt werden. Fig. 4 shows a further alternative embodiment of a suction device 200. In this case, the blower is set up to supply the gas flow to the constriction through an air duct 400 with a thickness between 0.1 mm and 1 mm, so that the gas flow 204 forms an air knife. In this embodiment, the mechanical barrier 204 extends from the narrow point 202 in the transport direction 3 as a ramp with a rounded shape with increasing distance from the recording medium 120. The air duct 400 is here positively connected to one end of the ramp in the transport direction 3, so that the fan 203 causes a gas flow 204 laminar parallel to the ramp. This gas stream 204 along the rounded ramp forms a so-called “Coanda flow”. This consists of a boundary layer, a relatively thin, undisturbed layer of air, the jet flowing along the ramp, then a further friction layer to the air masses outside the Coanda jet. The air outside is at rest, which is why there is no increase in pressure according to Bernulli's law. Therefore, the Coanda flow sticks to the ramp along which it flows longer than a normal flow. In this way, the boundary air layer on the recording medium 120 is entrained perpendicular to the transport direction 3 and can be sucked out.

Fig. 5 zeigt ein Ablaufdiagramm eines Verfahrens 300 zur Absaugung von Tintennebel 170 in einer Tintenstrahl-Druckvorrichtung 100. Die Druckvorrichtung 100 umfasst ein Druckwerk 140 zum Bedrucken der Vorderseite eines entlang einer Transportrichtung 1 durch das Druckwerk 140 bewegten Aufzeichnungsträgers 120. Fig. 5 shows a flowchart of a method 300 for suctioning ink mist 170 in an inkjet printing device 100. The printing device 100 comprises a printing unit 140 for printing on the front side of a recording medium 120 moved along a transport direction 1 through the printing unit 140.

Das Verfahren 300 umfasst das Führen 301 des Aufzeichnungsträgers 120 entlang der Transportrichtung 1 durch eine über der Vorderseite des Aufzeichnungsträgers 120 angeordneten Engstelle 202. Die Engstelle 202 kann dabei eine Höhe von 2-12mm aufweisen. Die Engstelle 202 kann ausgebildet sein, die mit dem Aufzeichnungsträger 120 an der Vorderseite des Aufzeichnungsträgers 120 mitgeführte Schicht mit Tintennebel 170 durch eine mechanische und/oder bauliche Blockade auf eine bestimmte Schichtdicke zu begrenzen. Dabei kann die Schichtdicke der Höhe der Engstelle 202 entsprechen.The method 300 includes guiding 301 the recording medium 120 along the transport direction 1 through a constriction 202 arranged above the front of the recording medium 120. The constriction 202 can have a height of 2-12 mm. The bottleneck 202 can be designed to be connected to the recording medium 120 Limit the layer with ink mist 170 carried on the front of the recording medium 120 to a certain layer thickness by a mechanical and / or structural blockage. The layer thickness can correspond to the height of the bottleneck 202.

Des Weiteren umfasst das Verfahren 300 das Bewirken 302 eines Gasstroms 204, insbesondere eines Luftstromes, der in der Engstelle 202 entgegen der Transportrichtung 1 über der bedruckten Vorderseite des Aufzeichnungsträgers 120 verläuft. Der Gasstrom 204 kann in besonders effizienter Weise durch ein in Bezug auf die Transportrichtung 1 hinter der Engstelle 202 angeordnetes Gebläse 203 bewirkt werden. Der Gasstrom 204 kann ausgebildet sein, die effektive Schichtdicke der Schicht mit Tintennebel 170 auf der Vorderseite des Aufzeichnungsträgers 120 weiter zu reduzieren, insbesondere um 50% oder mehr oder um 80% oder mehr zu reduzieren.Furthermore, the method 300 includes the effecting 302 of a gas stream 204, in particular an air stream, which runs in the constriction 202 counter to the transport direction 1 over the printed front side of the recording medium 120. The gas flow 204 can be effected in a particularly efficient manner by a blower 203 arranged behind the narrow point 202 with respect to the transport direction 1. The gas stream 204 can be designed to further reduce the effective layer thickness of the layer with ink mist 170 on the front side of the recording medium 120, in particular to reduce it by 50% or more or by 80% or more.

Das Verfahren 300 umfasst ferner das Absaugen 303 von Tintennebel 170 von der bedruckten Vorderseite des Aufzeichnungsträgers 120 in einem Absaugbereich, der in Bezug auf die Transportrichtung 1 vor der Engstelle 202 angeordnet ist. Der Tintennebel 170 kann durch eine Absaugeinheit 205 abgesaugt werden, die vor der Engstelle 202 angeordnet ist. Die kombinierte Verwendung einer mechanischen Engstelle 202 mit einem gegenläufigen Gasstrom 204 innerhalb der Engstelle 202 ermöglicht dabei eine effiziente und umfassende Absaugung des Tintennebel 170 in dem Absaugbereich vor der Engstelle 202.The method 300 further includes the suction 303 of ink mist 170 from the printed front of the recording medium 120 in a suction area which is arranged in front of the bottleneck 202 with respect to the transport direction 1. The ink mist 170 can be sucked off by a suction unit 205, which is arranged in front of the bottleneck 202. The combined use of a mechanical bottleneck 202 with a counter-rotating gas flow 204 within the bottleneck 202 enables efficient and comprehensive suction of the ink mist 170 in the suction area in front of the bottleneck 202.

Es wird somit in diesem Dokument eine Absaugvorrichtung 200 zur Absaugung von Tintennebel 170 in einer Tintenstrahl-Druckvorrichtung 100 beschrieben. Die Druckvorrichtung 100 kann, wie z.B. in Zusammenhang mit Fig. 1a beschrieben, ein Druckwerk 140 zum Bedrucken der Vorderseite eines entlang einer Transportrichtung 1 durch das Druckwerk 140 bewegten Aufzeichnungsträgers 120 aufweisen. Das Druckwerk 140 kann ein oder mehrere Druckriegel 102 und/oder Druckköpfe 103 aufweisen, die ausgebildet sind, Tintentropfen auf die Vorderseite des Aufzeichnungsträgers 120 aufzubringen.This document therefore describes a suction device 200 for suctioning ink mist 170 in an inkjet printing device 100. The printing device 100 can, for example, in connection with Fig. 1a described, have a printing unit 140 for printing on the front of a recording medium 120 moved along a transport direction 1 through the printing unit 140. The printing unit 140 can have one or more printing bars 102 and/or print heads 103, which are designed to apply drops of ink to the front of the recording medium 120.

Im Rahmen des Druckprozesses kann in dem Druckwerk 140 Tintennebel 170 erzeugt werden, der von dem sich in Transportrichtung 1 bewegenden Aufzeichnungsträger 120 in einer Tintennebel-Schicht an der Vorderseite des Aufzeichnungsträgers 120 mitgerissen wird.As part of the printing process, ink mist 170 can be generated in the printing unit 140, which is entrained by the recording medium 120 moving in the transport direction 1 in an ink mist layer on the front of the recording medium 120.

Die Absaugvorrichtung 200 umfasst eine mechanische Barriere 201, die ausgebildet ist, eine bauliche Engstelle 202 über der in dem Druckwerk 140 bedruckten Vorderseite des in Transportrichtung 1 an der mechanischen Barriere 201 vorbeigeführten Aufzeichnungsträgers 120 zu bilden. Die Engstelle 202 kann z.B. durch ein Blech gebildet werden, das über der Vorderseite des Aufzeichnungsträgers 120 angeordnet ist und das ggf. parallel zu der Vorderseite des Aufzeichnungsträgers 120 entlang der Transportrichtung 1 verläuft.The suction device 200 comprises a mechanical barrier 201, which is designed to form a structural constriction 202 over the front side of the recording medium 120, which is printed in the printing unit 140 and is guided past the mechanical barrier 201 in the transport direction 1. The bottleneck 202 can be formed, for example, by a sheet metal which is arranged over the front of the recording medium 120 and which, if necessary, runs parallel to the front of the recording medium 120 along the transport direction 1.

Die mechanische Barriere 201 kann ausgehend von dem der Engstelle 202 zugewandten Bereich eine Rampe bilden, die sich von der Vorderseite des Aufzeichnungsträgers 120 weg und entlang der Transportrichtung 1 erstreckt. So kann in zuverlässiger Weise bewirkt werden, dass der durch die Engstelle 202 abgeschöpfte Teil der Tintennebel-Schicht von dem Aufzeichnungsträger 120 weggeführt wird. So kann eine besonders zuverlässige Absaugung des Tintennebels 170 in einem Absaugbereich vor der Engstelle 202 ermöglicht werden.Starting from the area facing the bottleneck 202, the mechanical barrier 201 can form a ramp which extends away from the front of the recording medium 120 and along the transport direction 1. In this way, it can be reliably ensured that the part of the ink mist layer skimmed off through the bottleneck 202 is guided away from the recording medium 120. This makes particularly reliable suction of the ink mist 170 possible in a suction area in front of the bottleneck 202.

Die mechanische Barriere 201 kann z.B. ein Blech aufweisen, das sich zunächst parallel zu dem Aufzeichnungsträger 120 entlang der Transportrichtung 1 erstreckt, um die Engstelle 202 zu bilden, und das sich ausgehend von dem Ausgang der Engstelle 202 von dem Aufzeichnungsträger 120 weg erstreckt, um die Rampe zu bilden.The mechanical barrier 201 can, for example, have a sheet metal which initially extends parallel to the recording medium 120 along the transport direction 1 in order to form the constriction 202, and which extends away from the recording medium 120 starting from the exit of the constriction 202 in order to form the constriction 202 to form a ramp.

Die durch die mechanische Barriere 201 gebildete Engstelle 202 weist eine Länge von weniger als 25 mm, bevorzugt weniger als 10 mm , noch bevorzugter weniger als 5 mm, entlang der Transportrichtung 1 auf. 1 . Alternativ oder ergänzend kann die Engstelle 202 einen entlang der Transportrichtung 1 verlaufenden Tunnel für den Aufzeichnungsträger 120 bilden. Die Verwendung einer Engstelle 202, die eine bestimmte Maximal-Ausbreitung entlang der Transportrichtung 1 aufweist, ermöglicht eine besonders umfassende Blockade und Absaugung des Tintennebels 170.The constriction 202 formed by the mechanical barrier 201 has a length of less than 25 mm, preferably less than 10 mm, even more preferably less than 5 mm, along the transport direction 1. 1 . Alternatively or additionally, the bottleneck 202 can form a tunnel for the recording medium 120 running along the transport direction 1. The use of a bottleneck 202, which has a certain maximum spread along the transport direction 1, enables a particularly comprehensive blockage and suction of the ink mist 170.

Die Druckvorrichtung 100 weist typischerweise eine bestimmte Druckbreite quer zu der Transportrichtung 1 auf, über die die Vorderseite des Aufzeichnungsträgers 120 in dem Druckwerk 140 bedruckt wird. Die durch die mechanische Barriere 201 gebildete Engstelle 202 erstreckt sich bevorzugt über die gesamte Druckbreite der Druckvorrichtung 100. So kann der in dem Druckwerk 140 erzeugte Tintennebel 170 in besonders umfassender Weise blockiert und abgesaugt werden.The printing device 100 typically has a certain printing width transverse to the transport direction 1, over which the front of the recording medium 120 is printed in the printing unit 140. The constriction 202 formed by the mechanical barrier 201 preferably extends over the entire printing width of the printing device 100. In this way, the ink mist 170 generated in the printing unit 140 can be blocked and sucked out in a particularly comprehensive manner.

Die Absaugvorrichtung 200 umfasst ferner ein Gebläse 203, das ausgebildet ist, in der Engstelle 202 über der bedruckten Vorderseite des Aufzeichnungsträgers 120 einen entgegen der Transportrichtung 1 verlaufenden Gasstrom 204 zu bewirken. Das Gebläse 203, insbesondere das sogenannte Airknife/Luftmesser, kann in Bezug auf die Transportrichtung 1 am Ausgang der Engstelle 202 angeordnet sein, und kann ausgebildet sein, einen Gasstrom 204, insbesondere einen Luftstrom, zu bewirken, der von dem Ausgang in Richtung Eingang der Engstelle 202 verläuft. Der von dem Gebläse 203 bewirkte Gasstrom 204 kann dabei ausgebildet sein, Tintennebel 170, der von der Vorderseite des Aufzeichnungsträgers 120 in Transportrichtung 1 von dem Eingang der Engstelle 202 in Richtung zu dem Ausgang der Engstelle 202 mitgerissen wird, zurück in Richtung zu dem Eingang der Engstelle 202 zu drücken. So kann in zuverlässiger Weise bewirkt werden, dass Tintennebel 170 an der mechanischen Barriere 201 blockiert wird, und somit nicht in eine der Absaugvorrichtung 200 nachgelagerte Komponente 150 der Druckvorrichtung 100 gelangen kann.The suction device 200 further comprises a blower 203, which is designed to cause a gas flow 204 running counter to the transport direction 1 in the constriction 202 above the printed front side of the recording medium 120. The blower 203, in particular the so-called airknife/air knife, can be arranged at the exit of the bottleneck 202 with respect to the transport direction 1, and can be designed to cause a gas flow 204, in particular an air flow, which flows from the exit towards the entrance of the Bottleneck 202 runs. The gas flow 204 caused by the blower 203 can be designed to be ink mist 170, which is entrained from the front of the recording medium 120 in the transport direction 1 from the entrance of the narrow point 202 towards the exit of the narrow point 202, back towards the entrance of the To push bottleneck 202. In this way, it can be reliably ensured that ink mist 170 is blocked on the mechanical barrier 201 and thus cannot reach a component 150 of the printing device 100 downstream of the suction device 200.

Der von dem Gebläse 203 bewirkte Gasstrom 204 kann insbesondere derart ausgebildet sein, dass der Tintennebel 170 in dem Absaugbereich vor der Engstelle 202, insbesondere direkt an der Vorderseite des Aufzeichnungsträgers 120, eine Bewegungsgeschwindigkeit in Transportrichtung 1 aufweist, die kleiner, insbesondere um einen Faktor 2 oder mehr kleiner, als die Transportgeschwindigkeit des Aufzeichnungsträgers 120 ist. Durch den Gasstrom 204 kann somit bewirkt werden, dass die Tintennebel-Schicht an der Vorderseite des Aufzeichnungsträgers 120, vor dem Eingang der Engstelle 202, abgebremst wird, um in zuverlässiger Weise die Menge an Tintennebel 170 zu reduzieren, die die Engstelle 202 durchläuft.The gas flow 204 caused by the blower 203 can in particular be designed such that the ink mist 170 in the suction area in front of the bottleneck 202, in particular directly on the front of the recording medium 120, has a movement speed in the transport direction 1 which is smaller, in particular by a factor of 2 or more smaller than the transport speed of the recording medium 120. The gas flow 204 can thus cause the ink mist layer on the front of the recording medium 120, in front of the entrance to the bottleneck 202, to be braked in order to reliably reduce the amount of ink mist 170 that passes through the bottleneck 202.

Alternativ oder ergänzend kann der von dem Gebläse 203 bewirkte Gasstrom 204 ausgebildet sein, die effektive Querschnittsfläche der Engstelle 202 senkrecht zu der Vorderseite des Aufzeichnungsträgers 120, durch die Tintennebel 170 durch die Engstelle 202 strömen kann, gegenüber der tatsächlichen Querschnittsfläche der Engstelle 202 zu reduzieren, insbesondere um 50% oder mehr oder um 80% oder mehr zu reduzieren. Der Gasstrom 204 ermöglicht es somit, eine relativ hohe Engstelle 202 zu verwenden, um in zuverlässiger Weise eine Kollision zwischen dem Aufzeichnungsträger 120 und der mechanischen Barriere 201 zu vermeiden, und dabei dennoch eine zuverlässige Abscheidung des Tintennebels 170 zu bewirken.Alternatively or additionally, the gas flow 204 caused by the fan 203 can be designed to reduce the effective cross-sectional area of the constriction 202 perpendicular to the front of the recording medium 120, through which ink mist 170 can flow through the constriction 202, compared to the actual cross-sectional area of the constriction 202, in particular to reduce by 50% or more or by 80% or more. The gas stream 204 thus makes it possible to use a relatively high constriction 202 in order to reliably prevent a collision between the recording medium 120 and the mechanical barrier 201 avoid, and still ensure reliable deposition of the ink mist 170.

Insgesamt kann die Ansaugvorrichtung 200 ausgebildet sein, zu bewirken, dass aus dem Ausgang der Engstelle 202 höchstens 10% des von dem Aufzeichnungsträger 120 an den Eingang der Engstelle 202 geführten Tintennebels 170 austritt. Dies kann in zuverlässiger Weise durch die Kombination aus einer mechanischen und/oder baulichen Engstelle 202 und einem gegenläufigen Gasstrom 204 bewirkt werden.Overall, the suction device 200 can be designed to ensure that a maximum of 10% of the ink mist 170 guided from the recording medium 120 to the entrance of the narrow point 202 emerges from the exit of the narrow point 202. This can be achieved in a reliable manner by the combination of a mechanical and/or structural bottleneck 202 and a counter-rotating gas flow 204.

Die Absaugvorrichtung 200 umfasst ferner eine Absaugeinheit 205, die eingerichtet ist, in einem Absaugbereich, der in Bezug auf die Transportrichtung 1 vor der Engstelle 202 angeordnet ist, Tintennebel 170 von der bedruckten Vorderseite des Aufzeichnungsträgers 120 abzusaugen. Die Ansaugeinheit 205 ist zu diesem Zweck vor der Engstelle 202 angeordnet. Ferner weist die Ansaugeinheit 205 bevorzugt eine der Vorderseite des Aufzeichnungsträgers 120 zugewandte Ansaugöffnung auf, die sich zu der Vorderseite des Aufzeichnungsträgers 120 hin aufweitet und/oder die sich mit zunehmendem Abstand von der Vorderseite des Aufzeichnungsträgers 120 verjüngt. So kann eine besonders effiziente und umfassende Absaugung des Tintennebels 170 in dem Absaugbereich vor der Engstelle 202 bewirkt werden.The suction device 200 further comprises a suction unit 205, which is set up to suck ink mist 170 from the printed front side of the recording medium 120 in a suction area which is arranged in front of the bottleneck 202 with respect to the transport direction 1. For this purpose, the suction unit 205 is arranged in front of the bottleneck 202. Furthermore, the suction unit 205 preferably has a suction opening facing the front of the recording medium 120, which widens towards the front of the recording medium 120 and/or which tapers as the distance from the front of the recording medium 120 increases. In this way, a particularly efficient and comprehensive suction of the ink mist 170 can be effected in the suction area in front of the bottleneck 202.

Es wird somit eine Absaugvorrichtung 200 für eine Tintenstrahl-Druckvorrichtung 100 beschrieben, die ausgebildet ist, einen bedruckten Aufzeichnungsträger 120 entlang einer Transportrichtung 1 durch eine mechanische Engstelle 202 mit einem gegenläufigen Gasstrom 204 zu führen, um in effizienter und umfassender Weise Tintennebel 170 in Transportrichtung 1 vor der Engstelle 202 absaugen zu können.A suction device 200 for an inkjet printing device 100 is thus described, which is designed to guide a printed recording medium 120 along a transport direction 1 through a mechanical bottleneck 202 with a counter-rotating gas flow 204 in order to efficiently and comprehensively ink mist 170 in the transport direction 1 to be able to vacuum in front of the bottleneck 202.

Des Weiteren wird in diesem Dokument eine Druckvorrichtung 100 beschrieben, die die in diesem Dokument beschriebene Absaugvorrichtung 200 umfasst.Furthermore, a printing device 100 is described in this document, which includes the suction device 200 described in this document.

Durch die in diesem Dokument beschriebenen Maßnahmen kann der in einem Druckwerk 140 erzeugte Tintennebel 170 zuverlässig beseitigt werden, insbesondere um eine Verschmutzung von nachgelagerten Komponenten wie einer Trocknungseinheit 150 zu vermeiden.Through the measures described in this document, the ink mist 170 generated in a printing unit 140 can be reliably eliminated, in particular in order to avoid contamination of downstream components such as a drying unit 150.

BezugszeichenlisteReference symbol list

11
TransportrichtungTransport direction
21, 2221, 22
Düse (Druckbild)Nozzle (print image)
31, 3231, 32
Spalte (des Druckbildes)Column (of the print image)
100100
DruckvorrichtungPrinting device
101101
SteuereinheitControl unit
102102
DruckriegelPressure latch
103103
DruckkopfPrinthead
120120
AufzeichnungsträgerRecord carrier
140140
DruckwerkPrinting unit
150150
Fixier- bzw. TrocknungseinheitFixing or drying unit
155155
Gehäuse (Trocknungseinheit)Housing (drying unit)
170170
TintennebelInk mist
200200
AbsaugvorrichtungSuction device
201201
mechanische Barrieremechanical barrier
202202
Spalt / Engstelle / BlockadestelleGap / bottleneck / blockage point
203203
Gebläsefan
204204
Gasstromgas flow
205205
AnsaugeinheitSuction unit
300300
Verfahren zur Absaugung von TintennebelMethod for extracting ink mist
301-303301-303
VerfahrensschritteProcedural steps

Claims (10)

  1. A suction device for sucking off ink mist (170) in an inkjet printing device (100), the printing device (100) having a printing unit (140) for printing on a front side of a recording medium (120) moved along a transport direction (1) through the printing unit (140), the suction device (200) comprising,
    - a mechanical barrier (201) configured to form a constriction (202) above the front side, printed in the printing unit (140), of the recording medium (120) guided past the mechanical barrier (201) in transport direction (1),
    the constriction (202) forming a tunnel for the recording medium (120) and having an extension of less than 25 mm in transport direction;
    - a blower (203) configured to cause a flow of gas (204) in the constriction (202) above the printed front side of the recording medium (120) in the opposite direction to the transport direction (1); and
    - a suction unit (205) configured to suck off ink mist (170) from the printed front side of the recording medium (120) in a suction area located upstream of the constriction (202) with respect to the transport direction (1).
  2. The suction device (200) according to claim 1, wherein the constriction (202) has an extension in transport direction (3) of less than 15 mm, preferably of less than 5 mm, more preferably of less than 2 mm.
  3. The suction device (200) according to claim 1 or 2, wherein the mechanical barrier (201), in transport direction (3) from the constriction (202), extends as a ramp with increasing distance to the recording medium (120) to guide a flow of gas (204) of the blower (203) to the constriction (202) in opposite direction to the transport direction (3).
  4. The suction device (200) according to claim 3, wherein the mechanical barrier (201) is ended after the constriction (202) in the direction opposite to the transport direction so that the flow of gas (204) of the blower (203) opposite to the transport direction (3) after the constriction (202) results in turbulent air turbulences so that air from the boundary air layer is carried away vertically to the transport direction (3).
  5. The suction device according to claim 3, wherein the mechanical barrier (201) extends opposite to the transport direction (3) after the constriction (202) in a round manner as a ramp with increasing distance to the recording medium (120) so that the flow of gas (204) of the blower (203) after the constriction (202) flows in a laminar manner along the round shape with increasing vertical distance to the recording medium (120) and thus air from the boundary air layer is carried away vertically to the transport direction (3) and the laminar flowing boundary air layer detaches from the recording medium (120).
  6. The suction device (200) according to one of the claims 3 to 5, wherein the mechanical barrier (201) extends from the constriction (202) in transport direction (3) as a ramp with a round shape with increasing distance to the recording medium (120).
  7. The suction device according to one of the preceding claims, wherein the blower (203) is configured to feed the flow of gas to the constriction through an air channel (400) with a thickness between 0.1 mm and 1 mm so that the flow of gas (204) forms an air knife.
  8. The suction device according to claim 7, wherein the air channel (400) forms an angle between 10° and 80°, preferably between 20° and 70°, more preferably between 30° and 60° to the transport direction (3).
  9. A method for sucking off ink mist (170) in an inkjet printing device (100), wherein the printing device (100) has a printing unit (140) for printing a front side of a recording medium (120) moved along a transport direction (1) through the printing unit (140), the method (300) comprising:
    - guiding (301) the recording medium (120) along the transport direction (1) through a constriction (202) arranged above the front side of the recording medium (120), the constriction (202) forming a tunnel for the recording medium (120) and having an extension of less than 25 mm in transport direction;
    - causing (302) a flow of gas (204) flowing in the constriction (202) opposite to the transport direction (1) above the printed front side of the recording medium (120); and
    - sucking off (303) ink mist (170) from the printed front side of the recording medium (120) in a suction area which is located upstream of the constriction (202) with respect to the transport direction.
  10. The method according to claim 9, which is implemented with a suction device according to one of the claims 1 to 8.
EP22721693.4A 2021-04-08 2022-04-07 Device and method for suctioning ink mist Active EP4153431B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102021108768.6A DE102021108768A1 (en) 2021-04-08 2021-04-08 Device and method for suction of ink mist
PCT/EP2022/059322 WO2022214619A1 (en) 2021-04-08 2022-04-07 Device and method for suctioning ink mist

Publications (2)

Publication Number Publication Date
EP4153431A1 EP4153431A1 (en) 2023-03-29
EP4153431B1 true EP4153431B1 (en) 2023-12-13

Family

ID=81386858

Family Applications (1)

Application Number Title Priority Date Filing Date
EP22721693.4A Active EP4153431B1 (en) 2021-04-08 2022-04-07 Device and method for suctioning ink mist

Country Status (4)

Country Link
US (1) US20230382118A1 (en)
EP (1) EP4153431B1 (en)
DE (1) DE102021108768A1 (en)
WO (2) WO2022214343A1 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2024115023A1 (en) * 2022-12-02 2024-06-06 Memjet Technology Limited Compact printing unit with integrated aerosol extraction unit
WO2024115022A1 (en) * 2022-12-02 2024-06-06 Memjet Technology Limited Aerosol extractor for inkjet printing system

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010143060A (en) 2008-12-18 2010-07-01 Olympus Corp Image forming apparatus
JP5326671B2 (en) * 2009-03-05 2013-10-30 セイコーエプソン株式会社 Fluid ejection device and fluid ejection device control method
JP2010201874A (en) 2009-03-05 2010-09-16 Seiko Epson Corp Fluid injection device and control method therefor
JP2010284892A (en) 2009-06-11 2010-12-24 Ricoh Co Ltd Image forming apparatus
JP5918986B2 (en) 2011-12-07 2016-05-18 株式会社ミマキエンジニアリング Inkjet device
JP6456069B2 (en) * 2013-09-20 2019-01-23 キヤノン株式会社 Liquid ejection device, mist collecting mechanism and mist collecting method
EP3072695B1 (en) * 2015-03-19 2020-01-15 Canon Kabushiki Kaisha Liquid ejecting apparatus
JP6529296B2 (en) * 2015-03-19 2019-06-12 キヤノン株式会社 Liquid discharge device and liquid discharge head
US10155390B2 (en) * 2015-04-20 2018-12-18 Hewlett-Packard Development Company, L.P. Aerosol control in a printer

Also Published As

Publication number Publication date
US20230382118A1 (en) 2023-11-30
EP4153431A1 (en) 2023-03-29
WO2022214343A1 (en) 2022-10-13
WO2022214619A1 (en) 2022-10-13
DE102021108768A1 (en) 2022-10-13

Similar Documents

Publication Publication Date Title
EP4153431B1 (en) Device and method for suctioning ink mist
EP1923216B1 (en) Printing device for suctioning off ink mist
DE102009048928A1 (en) Inkjet printer for printing on sheet-shaped substrate, has printing unit transport device including conveyor belt with drive device that impresses speed to belt, where printing sheet or substrate is provided with certain distance to belt
DE69208751T2 (en) Continuous ink jet catcher with improved flow control design
EP3265240B1 (en) Coating device comprising an adjustable tear-off edge
EP3927554B1 (en) Printing machine
DE102009007800A1 (en) Aerosol printers, their use and methods of producing line breaks in continuous aerosol printing processes
EP4065376A1 (en) Printing machines and method for cleaning at least one nozzle bar of at least one printing assembly
DE60206566T2 (en) Liquid ejection system with little contamination
EP2042316B1 (en) Powder device
DE19527441A1 (en) Method and device for pneumatic sheet braking in the delivery of a sheet-fed rotary printing machine
DE102017204632A1 (en) An ink jet printing machine having a transport path and an ink jet printhead
DE19810061A1 (en) System and method for reducing aerosol contamination in an ink jet printer
DE19901670C5 (en) Method and device for keeping clean and / or cleaning a sheet delivery of a sheet-fed offset printing press
DE19914563A1 (en) Method and apparatus for cleaning the outer surface of an endless conveyor belt of non-recording ink ejected from an ink jet recording apparatus
WO1999037484A1 (en) Method and device for preventing an uncontrolled powder dispersion in a printing machine
DE69004309T2 (en) Nozzle arrangement for color jet printers and working processes.
EP2869011A1 (en) Method and device for treating a sheet of material
DE102020117181B4 (en) Suction device for a recording medium
EP0812685A1 (en) Suction device for extracting air out of the nip between a web and a chill roll in a web-fed rotary offset printing press
DE102021116472A1 (en) SCANNING INKJET PRINTER
DE102005004500A1 (en) Air lock mechanism for printing press has grasp system of sheet delivery system which passes through first suction duct device which stands in assembled position adjacent to each grasp path area
DE10358754B4 (en) Rail conveyor
EP2888111B1 (en) Printing apparatus and printing method
DE102020129870A1 (en) Sheet-fed printing machine with suction belt and covering device

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: UNKNOWN

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20221221

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: GRANT OF PATENT IS INTENDED

DAV Request for validation of the european patent (deleted)
DAX Request for extension of the european patent (deleted)
INTG Intention to grant announced

Effective date: 20230808

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE PATENT HAS BEEN GRANTED

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

Free format text: NOT ENGLISH

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

REG Reference to a national code

Ref country code: DE

Ref legal event code: R096

Ref document number: 502022000325

Country of ref document: DE

P01 Opt-out of the competence of the unified patent court (upc) registered

Effective date: 20231122

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

Free format text: LANGUAGE OF EP DOCUMENT: GERMAN

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20240314

REG Reference to a national code

Ref country code: LT

Ref legal event code: MG9D

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231213

REG Reference to a national code

Ref country code: NL

Ref legal event code: MP

Effective date: 20231213

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231213

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231213

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20240314

Ref country code: ES

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231213

Ref country code: BG

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20240313

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231213

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231213

Ref country code: RS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231213

Ref country code: NO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20240313

Ref country code: NL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231213

Ref country code: LV

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231213

Ref country code: HR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231213

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20240413