EP2011654B1 - Creation and deflection of ink drops in a continuously working ink jet printer - Google Patents

Abstract

The method involves exiting a continuous cohesive ink jet (9) from a nozzle (6) of a pressure chamber (5), so that an acoustic pulse (140) strikes the cohesive ink jet transversely to propagation direction. A segment of the inkjet upon which the acting acoustic pulse is separated from the cohesive ink jet and deflected from an original propagation direction (100) of the segment, such that the separated segment forms an ink drop during the travel due to cohesion forces. The ink drop is selectively separated from the continuous and cohesive ink jet using the acoustic pulses. An independent claim is also included for a device for producing and deflecting ink drops from a cohesive inkjet.

Description

The invention relates to a method for producing and deflecting ink droplets of a continuous ink jet printer in which a continuous coherent ink jet emerges from a nozzle of a pressure chamber. The invention further relates to an apparatus for generating and deflecting ink droplets from a coherent ink jet comprising a pressure chamber having a nozzle for generating a continuously emerging contiguous ink jet.

Continuous inkjet printers have been used industrially for many years to label a variety of products. The previous operating principle of this inkjet printer works so that an ink to be printed from a reservoir via pumps with positive pressure is conveyed into a located in the actual print head pressure chamber, which has a nozzle on the side facing the material to be printed.

The nozzle in this case has an opening diameter in the range of eg 30μ to 200μm. From the nozzle now the ink jet initially emerges as a continuous ink jet, which is impractical for a label, since the characters generated here are constructed in this type of labeling of individual dots or individual ink droplets.

In order to decompose the ink jet into individual similar drops of ink, a modulation element is mounted on the pressure chamber, which generates pressure fluctuations in the exiting ink jet, so that after leaving the nozzle after a short time at a defined distance breaks up into individual similar drops of ink. The size of the ink droplets depends on the applied modulation frequency, the nozzle diameter and the pressure generated by the pump, and can be adjusted within the limits set for the system by the combination of said parameters. A variation of the droplet size of successive ink droplets is not possible.

Shortly before the tearing off of the ink drops from the leaked ink jet, the ink droplets are each provided with an individual electrical charge, the height of the charge depending on the desired impact position on the product to be labeled. To ensure electrical charging, the ink has a low electrical conductivity.

During the charging process, the ink droplet has not yet broken off from the ink jet emanating from the nozzle of the ink jet printer, so that due to electrical influence free charge carriers in the ink are moved towards or away from the charging electrode, depending on the polarity and magnitude of an external charging voltage Ink chamber and thus the ink reservoir, for example, electrically held at ground potential. The charging electrode has no mechanical contact with the ink jet.

If the ink droplet now tears off the ink jet while it is in the field region of the charging electrode, then the electrical charges migrated through the influence in the droplets remain in the drop volume and this appears to be electrically charged even after the demolition. For example, if the charging electrode charged positively, so wander at the onset of Ink jet into the electric field of the charging electrode, the negative free charge carriers in the ink into the field, whereas the positively charged free charge carriers in the ink are expelled from the electric field.

As a result, a charge separation takes place immediately prior to the demolition of the droplet at the leading edge of the ink jet, and the charge imbalance thus created in the tearing droplet is retained and the droplet leaves the field region of the charging electrode negatively charged in this example.

Since the ink droplet tears off due to the design and principle during the influence of the charging voltage on the droplet, as described on the detached ink droplet, a charge back whose size at a constant electrical conductivity of the ink according to the height of the applied charging voltage and thus with a change in the charging voltage Also, the amount of charge on each drop can be changed.

On their initially straightforward flight, the electrically charged ink droplets subsequently enter the electrostatic field of a plate capacitor and, depending on their individual charge, are more or less deflected from their rectilinear trajectory and, upon leaving the electrostatic field, fly at a certain angle dependent on their charge continue to their original trajectory.

With this principle, different impact positions can be selected on a surface to be labeled with individual ink droplets, which in this embodiment takes place only in a deflection direction. To hide individual drops from the typeface or when not to be printed, the ink drops receive a certain fixed charge or remain uncharged, so that after exiting the electrostatic field of the Condenser plate in a collecting tube from where they are pumped back via a pump system in the ink tank. This causes the unprinted ink to circulate, resulting in the designation of continuous ink jet printers.

A disadvantage of the described conventional design is that due to the systemic deflection of the ink droplets, the ink itself must have a low electrical conductivity, albeit low, so that the individual charge amount required for the electrostatic deflection can be applied to each individual ink droplet.

This limits the number of usable inks because it is not possible or convenient for any desired ink composition to provide these by themselves or via additives with an electrical conductivity. By way of example, this may be an ink which has magnetic properties. Such an ink could, for example, be made electrically conductive by means of an additive, but the trajectories of the respective ink droplets can not be controlled due to the induction phenomena that occur and the associated different additional deflection forces.

The DE 103 07 055 in contrast, describes a method for deflecting ink drops, which deflects the ink drops generated in the usual way by pressure modulation in the ink by means of an ultrasonic wave depending on the applied sound energy to different degrees.

An advantage of this type of deflection is that the inks to be printed no longer need to have electrical conductivity, which allows the use of a large number of different inks with very different properties.

Disadvantageous in the DE 103 07 055 is that on the one hand a precise synchronization between the drop generation and the drop deflection must be made, which must also take into account the finite speed of propagation of the sound waves at the location of the deflection depending on the local environmental conditions to a precise deflection of an ink drop to the desired position to enable. A further disadvantage is that when using a simple sound generator due to the size of the sound-generating surface, the acting sound energy acts not only exclusively on the ink drops to be deflected, but at least partially on vorausfliegende and subsequent drops, whereby a precise deflection of the ink drops is only partially possible. A further disadvantage is that the deflected ink drops all have the same size due to their production, whereby a typeface with different weights only by an overlay of several ink droplets can be generated and thus only in stages can be generated.

The document WO 2006/076195 A2 shows an apparatus for the hydraulic sorting of particles, such as blood cells, in which particles of interest are sorted out by a hydraulic pulse from a sequence of particles.

The object of the invention is to provide a method and a device with which it is possible to eliminate the disadvantages mentioned. The object of the invention is furthermore to provide a method and a device with which it is possible to produce different sized ink droplets within a label to be applied and to divert them into a desired direction of flight.

The object is achieved according to the invention in that, in contrast to the known technique, the production of individual ink droplets from a continuous and contiguous ink jet after exiting the ink jet from the nozzle of the pressure chamber is effected by at least one sound pulse being directed laterally of the propagation direction onto the contiguous ink jet, and a portion of the ink jet acting on the sound pulse from the contiguous ink jet is removed and deflected out of its original direction of propagation, wherein the liberated section by cohesion forces during flight forms an ink drop.

Furthermore, the object is achieved by a device of the aforementioned generic type, in which at least one sound generator outside the pressure chamber and the side of the ink jet is arranged, with the at least one directed to the ink jet sound pulse can be generated by the ink jet from the ink drops liberated and out their original direction are distractible.

By means of a sound pulse, preferably a bundled ultrasonic pulse or hypersonic pulse, a certain portion of the contiguous ink jet can be released and this portion can be deflected in a deviating from the original trajectory trajectory. This is achieved according to the invention in that the side of the jet of ink leaving the nozzle of the pressure chamber; Preferably arranged at a 90 ° angle, at least one sound generator is arranged, which is controlled by a suitable electrical control via a higher-level control and in particular emits short sound pulses, which propagate as a pulse-like sound pressure wave in the direction of the ink jet.

It may preferably be provided according to the invention to focus the sound pulse, for example, characterized in that between each of the at least one sound generator and the ink jet, a focusing device for the sound pulses are arranged, with which the sound waves emitted by each sound generator of the sound pulse are focused into a respective focal point.

According to the invention, it can be provided that the ink jet passes through the respective focal points, so that the sound energy of the sound pulses can act on the ink jet in the best possible way. If, for example, the contiguous ink jet in the focal point of a first sound generator system is struck by at least one sound pulse, a specific section of the ink jet is released by means of the energy transmitted to the ink jet via the sound pulse and the associated sound pulse, whereby the ink jet is interrupted.

As a motion pulse is transmitted transversely to its original trajectory on the detached portion of the ink jet on the sound pulse at the same time, the detached portion leaves the original trajectory of the ink jet and flies at a certain angle to the original Fugbahn on.

Along its further path, this ink jet-released portion forms into an ink drop due to the cohesive forces of the ink. Depending on the nature of the at least one sound pulse and its time sequence, it is possible according to the invention, for example, with the detachment of a portion of the ink jet this same transmittance of a certain required momentum for a certain change in direction transverse to the original trajectory, resulting in the detached from this section Drops of ink assumes a new trajectory inclined to the original trajectory.

By a variation, for example, the duration of the sound pulse and / or the intensity of the sound pulse and / or the frequency spectrum of the sound pulse and / or its focusing, it is also possible according to the invention, individual Detaching drops of ink from a continuous and contiguous ink jet and impart different inclined directions of flight to these liberated ink drops to the original direction of flight.

This makes it possible that the trajectories of the respective ink droplets are fan-shaped to each other, whereby, for example, in a deflection in a transverse direction to the original trajectory, a pressure line can be written. Those areas of the ink jet, which are not needed for a printing line to be built up and which accordingly also do not experience any distraction by a sound pulse, arrive in the usual manner in the collecting opening of a catching pipe and are transported back into the ink circulation, for example by means of a pump.

In a further embodiment, it may be provided according to the invention to provide, in addition to a first sound generator for producing individual ink droplets from a continuous and contiguous ink jet, at least one second sound generator which essentially serves to deflect the ink droplets released and in particular already deflected once. Here, for example, by the first sound generator, in particular by means of a sequence of sound pulses of the same energy, intensity, duration and frequency composition of the continuous and contiguous ink jet single drops of ink of substantially the same size dissolved out, which are deflected in a certain angle to the original direction of flight in a second direction of flight ,

The ink droplets thus produced are then deflected while passing through the focal point, in particular the focusing device of the second sound generator with different sound pulses in each case in different different deflection directions, resulting in a fan-shaped to each other crowd of flight directions. It may be expedient here, by means of first sound generator in a first embodiment to produce only those drops of ink from the continuous and contiguous ink jet, which are actually needed in a print image to be written or in a second embodiment by means of the first sound generator to produce a continuous train of ink drops and only those for a print image required ink droplets continue to deflect by means of the second sound generator system, so that in each case only a single catching device for the unneeded portions of the ink may be present.

As sound generators for generating individual ink droplets and / or their deflection, for example, all known methods for generating sound can be used such as electrodynamic transducers, piezoelectric transducers, electrostrictive transducers, magnetostrictive transducers, electrostatic transducers, plasma generators, etc. according to the invention at least a portion of the generated sound waves in to focus on a focal point.

For this purpose, for example, an acoustic lens, a reflector material or a combination thereof can be used. According to the invention, it can also be provided to design the sound generator and in particular one or more sound-generating surfaces or sound-generating elements such that their shape or arrangement acts like the Fourier transform of a punctiform sound event and thus generates in its "reverse operation" sound waves which emanate from this generator and in the Essentially focused in a focal point, which lies on the ink jet.

For this purpose, the sound-generating surface in a simple case, for example, be designed as a Fresnel zone plate, wherein the sound-generating surface is divided into individual concentrically regions each individually controllable electrically. By appropriate electrical control of the respective Areas with respect to amplitude, phase position, time course and frequency spectrum, it is possible to generate a corresponding sound pulse without additional acoustic lenses or reflectors and to focus this in a focal point. It may also be expedient to generate a plurality of mutually independent acoustic focal points in a corresponding embodiment of the sound-generating surface and a corresponding electrical control of the respective areas, so as to produce, for example, in a first focal point ink droplets and in a second subsequent focus to deflect this individually. Here, the different focus can be generated by the same sound generator.

Figur 1:

eine Anordnung zur Erzeugung von Tintentropfen und deren Ablenkung gemäß des Standes der Technik

Figur 2:

eine erste erfindungsgemäße Ausführung zur Erzeugung von Tintentropfen und deren Ablenkung mit einem Schallerzeugersystem

Figur 3:

eine zweite erfindungsgemäße Ausführung zur Erzeugung von Tintentropfen und deren Ablenkung mit einem fouriertransformierten Schallerzeugersystem

Figur 4:

eine dritte erfindungsgemäße Ausführung mit zwei voneinander unabhängigen Schallerzeugersystemen

Figur 5:

eine vierte erfindungsgemäße Ausführung mit drei voneinander unabhängigen Schallerzeugersystemen

Figur 6:

eine fünfte erfindungsgemäße Ausführung mit einem fouriertransformierten Schallerzeugersystem mit zwei voneinander unabhängigen Brennpunkten

Embodiments and the prior art show the following figures: It shows:

FIG. 1:

an arrangement for the production of ink drops and their deflection according to the prior art

FIG. 2:

a first embodiment of the invention for generating ink drops and their deflection with a sound generator system

FIG. 3:

a second embodiment of the invention for generating ink drops and their deflection with a Fourier transformed sound generator system

FIG. 4:

a third embodiment of the invention with two independent sound generator systems

FIG. 5:

a fourth embodiment of the invention with three independent sound generator systems

FIG. 6:

a fifth embodiment of the invention with a Fourier transformed sound generator system with two independent focal points

FIG. 1 shows for comparison with the invention by way of example a printhead of the known type of continuous ink jet printer. The ink 1 is first pumped from a reservoir 2 by means of a pump 3 via leads 4a into the pressure chamber 5, at one end of which a nozzle 6 is introduced. By means of additionally mounted on the pressure chamber modulation means 7, the pressure in the pressure chamber 5 is modulated so that the emerging from the nozzle 6 ink jet breaks 9 at a short distance after its exit into individual ink droplets 11 of substantially the same size. Shortly before breaking up, the individual ink droplets 11 are provided with an individual electrical charge via a charging electrode 8.

Along their trajectory 100, the ink drops 11 now enter an electric field 21, which is formed by means of the electrodes 20a and 20b of the plate capacitor 20. Depending on the charge quantity and the polarity of the charges on the ink droplets 11 and the polarity and strength of the electric field 21 in the field space of the plate capacitor 20, the individual ink droplets are deflected into different spatial directions 101, 102 shown by way of example.

The total number of possible deflection angles depends only on the control of the charging electrode and is not limited in principle. The individual plates 20a and 20b of the plate capacitor 20 may be inclined relative to each other, as in FIG. 1 shown. However, it is also possible to use plates arranged parallel to one another without restriction of generality.

The polarity and strength of the electric field 21 is suitably kept substantially constant in this embodiment, since a change the field strength on a plurality of drops, which are at this time in the field space of the plate capacitor, simultaneously affects and thus an influence of a single drop is impossible.

After leaving the field space 21 of the plate capacitor 20 no more electrostatic force acts on the ink drops 11 and they maintain their new trajectories 101, 102 at. This results in a fan-shaped array of trajectories. For example, ink drops 11, which have not been charged or only slightly charged because they must be discarded from the typeface, experience no or only a slight deflection in the electrostatic field 21 of the plate capacitor 20 and strike into an opening 19 of a catch tube 18 for ink return. The ink thus collected is returned to the ink container 2 through leads 4b and returned to the ink circuit.

It is easy to see that this principle works only with inks which have an electrical conductivity, since otherwise an electrostatic charging of the ink drops can not take place.

FIG. 2 shows a first embodiment according to the invention for the generation and deflection of ink drops of a not necessarily electrically conductive ink and in particular an electrically non-conductive ink. The ink 1 is for this purpose pumped from a reservoir 2 by means of a pump 3 via leads 4a in a pressure chamber 5, at one end of which a nozzle 6 is located.

Due to the substantially static pressure generated by the pump 3 in the pressure chamber 5, the ink 1 exits the pressure chamber 5 via the nozzle 6 as a continuous and contiguous ink jet 9 along a propagation direction 100 and after a certain distance enters the area of the sound generation system 40. The sound generator system 40 includes, for example, a sound generator located in a holder 40d 40a, which has a focusing device 40b on its side facing the ink jet 9.

The distance of the sound generator system 40 to the ink jet 9 and in particular the configuration of the focusing device 40b are determined so that the focal point of the focusing device 40b strikes the ink jet 9 moving along the propagation direction 100. As a result, the sound waves 140 emitted from the sound generator 40a are concentrated in a small area on the ink jet 9 so that a certain sound energy and a certain sound pulse is transmitted to the ink jet 9 by the acting sound pulse, resulting in the continuous and contiguous ink jet 9 certain route section can be removed.

Depending on the used pulse duration, pulse shape, frequency composition and sound generated in the sound generator 40a sound energy while more or less sound energy and a more or less large sound pulse transmitted to the leached stretch section, so that the respective sections can experience different deflection angle and thus it is possible by to generate a corresponding control by means of a higher-level control, not shown selectively different deflection angle of individual sections and thus to address, for example, a pressure line.

After a short time due to the cohesive forces prevailing in the interior of the ink, the sections thus removed form individual ink droplets 13 along their respective further deflection directions 101, 102, which ink droplets 13 can be used in a known manner for labeling or marking.

Track sections that are not required for a typeface and thus must be discarded, learn no distraction on the sound generator system 40 so that they fly undistracted along their original direction of propagation 100 and enter a collecting opening 19 of a catch tube 18 and in a known manner via return lines 4b in the ink circulation are transported back.

FIG. 3 shows a second embodiment of the invention for generating ink droplets and their deflection, in which the sound generator system 42 is designed so that it can be operated as a Fourier transform a punctiform sound event. This makes it possible to operate such a sound generator system 42 without focusing since the sound waves 142 are bundled with a corresponding control of the sound generating segments 42a by superimposing the respective amplitudes and phases in a common focus 42c, which in a similar way individual sections of the Ink jet 9 can be removed and deflected.

A third embodiment of the invention for generating ink drops and their deflection shows FIG. 4 in which two independently operating sound generator systems 40 and 41 are provided. It is inventively provided with a first sound generator system 40 to disassemble the continuous and contiguous ink jet 9 into a continuous series of ink drops 11, for example by means of the sound generator system 40 with a sound pulse sequence of constant frequency on the propagating along its propagation direction 100 ink jet 9 is acted upon such that the ink jet 9 is decomposed into a series of substantially similar ink droplets 11 which are deflected in a new propagation direction 100a. By means of the subsequently arranged sound generator system 41, individual ink drops are synchronized with the drop frequency by means of subjected to at least one further sound pulse in such a way that they undergo a change in direction and depending on the intensity and time course of the applied sound pulse in a direction 101, 102 are deflected. Ink drops not required for a label, for example, are not subjected to sound pulses and therefore undergo no further deflection and strike in a known manner into a collecting opening 19 of a catching pipe 18 and are transported back into the ink circulation via return lines 4b.

A fourth embodiment of the invention for generating ink drops and their deflection shows FIG. 5 in which by means of a first sound generator system 40 from the continuous and contiguous ink jet 9, the ink drops required for a printed image are dissolved out so that they are deflected in a new deflection direction 100a. The sections of the ink jet 9 which are not required for the print image arrive in a collecting opening 19 a catching pipe 18 arranged immediately after the sound generator system 40 and are transported back into the ink circulation via return lines 4b. The ink droplets 11 dissolved out of the ink jet 9 are then acted on by one of the two following sound generator systems 41, 43 by means of sound pulses so that individual ink droplets 13 can be deflected in a new direction 101, 102, 103. It may be expedient that the respective focal points 41 c, 43 c of the sound generator systems 41, 43 coincide, so that the propagation direction 100 a mirror-image deflection directions are possible and the drops to be deflected always move through a focal point 41 c or 43 c.

A fifth embodiment of the invention for generating ink drops and their deflection shows FIG. 6 in which the sounder system 42 is designed to be Fourier-transformed for at least two point-shaped Sound events can be operated. In this case, for example, in a first area, a number of sound-generating segments 42a can be controlled via a higher-level control, not shown, such that their emitted sound waves 142a are bundled in a first focal point 42c. By an appropriate control of the sound generating segments 42a, it is thus possible the continuous and contiguous ink jet 9, which passes through the focal point 42c, in this completely separate into similar single ink droplets 11 and the ink droplets 11 thus produced from the original propagation direction 100 of the ink jet 9 in to divert a new propagation direction 100a.

A second number of sound-generating segments 42b in a subsequent region can, for example, each be controlled via a higher-level control (not shown) so that individual ink droplets can be deflected in different directions 101, 102. For this purpose, the propagation direction 100a of the ink droplets runs through the focal point 42e of the second segment arrangement 42b. Ink drops which should not be used for printing experience no distraction and are returned in the usual way in the ink circulation.

The advantage of using "Fourier-transformed" sound generator systems is that the position and shape of the Fourier-transformed sound event can be varied at the focal point by superimposing the sound waves emitted by all sound-generating segments, for example by varying the frequency spectrum, the time course of sound, for each segment. whose amplitudes and phase position are adjusted. This makes it possible, at least within certain limits, to influence the shape of the focal point and its position relative to the ink jet 9 and, if appropriate, for a certain distance entrain so as to achieve an optimal introduction of the sound energy in the ink jet.

Claims (23)

1. Method for producing and deflecting ink drops of a continuously operating inkjet printer, in which a continuous cohesive ink jet emerges from a nozzle of a printing chamber, wherein at least one sound pulse (140, 142, 142a) meets the cohesive ink jet (9) laterally with respect to the direction of propagation and a section of the ink jet (9), on which the sound pulse (140, 142, 142a) acts, is detached from the cohesive ink jet (9) and is deflected from its original direction of propagation (100), the detached section forming an ink drop (11) as a result of cohesive forces during the flight.
2. Method according to Claim 1, characterized in that at least one sound generator (40a, 42a) which can be actuated in a pulsed manner and is present outside the printing chamber (5) and is arranged along the direction of propagation (100) of the continuous and cohesive ink jet (9) is used for producing the at least one sound pulse (140, 142, 142a), at least one sound pulse (140, 142, 142a) which is directed laterally, in particular at a right angle to the continuous ink jet (9), being produced by the at least one sound generator (40a, 42a).
3. Method according to either of the preceding claims, characterized in that optionally ink drops (11) are detached from the continuous and cohesive ink jet (9) by sound pulses (140, 142, 140a) acting on the ink jet (9) transversely to the direction of propagation (100) of the ink jet (9).
4. Method according to any of the preceding claims, characterized in that the cohesive ink jet (9) is treated with successive sound pulses (140, 142, 142a) transversely to the direction of propagation (100) of the ink jet (9) in such a way that ink jet sections deflected (11) from the original direction of propagation (100) and undeflected (12) ink jet sections form, undeflected sections (12) entering a collecting device (18, 19) arranged in the original direction of propagation (100) and being transported back into the ink circulation.
5. Method according to any of the preceding claims, characterized in that the cohesive ink jet (9) is treated with successive sound pulses (140, 142, 142a) transversely to the direction of propagation (100) of the ink jet (9) in such a way that only ink jet sections (11) which are deflected from the original direction of propagation (100) and form ink drops (11) result.
6. Method according to any of the preceding claims, characterized in that the detached sections form ink drops (11) having substantially the same size.
7. Method according to any of the preceding claims, characterized in that the detached sections form ink drops (11) having a different size.
8. Method according to any of the preceding claims, characterized in that ink drops (11) detached from the ink jet (9) by at least one sound pulse (140, 141, 142, 142a) acting on the ink jet (9) transversely to the direction of propagation (100) of the ink jet (9) can be deflected in optionally different directions (101, 102).
9. Method according to any of the preceding claims, characterized in that the at least one sound pulse (140, 141, 142, 142a) is focused onto the cohesive ink jet (9).
10. Method according to Claim 9, characterized in that the at least one sound pulse (140, 141, 142, 142a) is focused by means of a focusing device (40b, 41 b), in particular onto a section of the cohesive ink jet (9).
11. Method according to any of the preceding claims, characterized in that the at least one sound pulse (140, 141, 142, 142a) is produced by means of at least one electrodynamic, electrostatic, magnetodynamic, magnetostatic or piezoelectric transducer (40a, 41 a, 42a).
12. Method according to any of the preceding claims, characterized in that the sound pulse (142, 142a,b) is produced by means of a sound generator (42) whose shape and/or arrangement of sound-producing elements (42a,b) corresponds to the Fourier transformation of a substantially point-like sound pulse (142, 142a,b) at a distance from the ink jet (9, 11), so that a sound pulse (142, 142a,b) which is focused without additional focusing elements onto the ink jet (9, 11) forms as a result of an actuation of the sound generator (42).
13. Method according to any of the preceding claims, characterized in that the focus of the sound pulse (142, 142a,b) follows the movement of the ink jet (9, 11) during the duration of said sound pulse (142, 142a,b).
14. Method according to any of the preceding claims, characterized in that, after a deflection of a section from the cohesive ink jet (9), at least one further sound pulse (141, 142b) acts on the ink drop (11) formed from this section, in order to deflect the drop (11) in a variable manner.
15. Method according to any of the preceding claims, characterized in that the extent of the deflection of a section or drop (11) depends on and/or is controlled by the energy and/or the momentum and/or the focusing of a sound pulse (140, 141, 142, 142a).
16. Method according to any of the preceding claims, characterized in that sound generators (41, 43) are arranged on two sides around a detached and deflected ink drop jet (11) or the original cohesive ink jet (9) in order optionally to produce a deflection of the ink drops (11) around the previous direction of propagation towards two different sides.
17. Inkjet printing device for producing and deflecting ink drops from a cohesive ink jet, comprising a printing chamber having a nozzle for producing a continuously emerging cohesive ink jet, wherein at least one sound generator (40a, 42a) is arranged outside the printing chamber (5) and to the side of the ink jet (9), by means of which it is possible to produce at least one sound pulse (140, 142, 142a) which is directed at the ink jet (9) and by means of which ink drops (11) can be detached from the ink jet (9) and can be deflected from their original direction (100).
18. Device according to Claim 17, characterized in that optionally ink drops (11) can be detached from the continuous and cohesive ink jet (9).
19. Device according to either of the preceding Claims 17 and 18, characterized in that ink drops (11) detached from the ink jet (9) by the same (40a, 42a) sound generator or at least one sound generator (41 a, 42a, 43a) following in the direction of propagation can be deflected in optionally different directions (101, 102, 103).
20. Device according to any of the preceding Claims 17 to 19, characterized in that the device comprises a collecting device (18, 19) and an ink circulation, the undetached regions (12) of the ink jet (9) entering the collecting device (18, 19) and being transported back into the ink circulation.
21. Device according to any of the preceding Claims 17 to 20, characterized in that a sound generator (40a, 41 a, 42a, 43a) is in the form of an electrodynamic and/or electrostatic and/or magnetodynamic and/or magnetostatic and/or piezoelectric transducer.
22. Device according to any of the preceding Claims 17 to 21, characterized in that it has a focusing device (40b, 41 b, 42b, 43b) for focusing the at least one sound pulse (140, 141, 142, 142a) onto a section of the cohesive ink jet (9) or a produced drop (11).
23. Device according to any of the preceding Claims 17 to 22, characterized in that the sound generator (42) has a shape and/or arrangement of sound-producing elements (42a) which corresponds to the Fourier transformation of a substantially point-like sound pulse at a distance from the ink jet (9, 11), so that a sound pulse (142, 142a) which is focused onto the ink jet (9, 11) without additional focusing elements can be produced by an actuation of the sound generator (42).

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