EP2052860A2 - Method and device for colour gradient prints - Google Patents

Abstract

The device has a color chamber (30) with an opening from which a color is applied on a color transfer roller (1). A mixing chamber (21) has two mixing compartments (29) arranged adjacent to each other parallel to the opening. The compartments have outlets arranged parallel to the opening over which the color chamber is filled with different mixed colors. The mixing chamber is cylindrically formed, and the compartments are separated from each other by partitions (24a). The partitions are fastened to a common driven and pivotably supported centric shaft (25). An independent claim is also included for a method for inking a color transfer roller with a color from a color chamber.

Description

The invention relates to an inking device for applying printing ink to a ink transfer roller comprising a paint chamber with an opening extending across the width thereof, from which ink can be applied to the ink transfer roller. The invention further relates to a method for coloring a Farbübertragswalze with color from a color chamber, wherein the color is applied through an opening of the ink chamber on the ink transfer roller for producing Farbverlaufsdrucken with at least two different printing inks.

For the application of printing ink to a color transfer roller of a printing unit, it is known to use a paint chamber having a paint chamber, which has an opening through which the ink is applied to a Farbübertragswalze a printing unit.

Such a paint chamber usually has a narrow side and a wide side, with the wide side extending along and parallel to the axis of rotation of the ink transfer roller. The opening, the width of which extends as well is limited by two narrow side shields of the ink chamber and two long squeegee, which are referred to as a working doctor blade and closing squeegee and bear in operation on the rotating ink transfer roller. Thus, in operation, the opening is closed by the lateral surface of the ink transfer roller, wherein the ink forms due to the rotation of the ink transfer roller in the ink chamber an equally and oppositely rotating ink roller, by the Recesses in the ink transfer roller ink is absorbed and transferred to another roller, for example, a further ink roller or a cliché-carrying roller.

Also, the generation of gradient prints with such color chambers, e.g. as a security feature has long been known. Here, for example, at least two different printing inks are applied in a printing unit on the lateral surface of a ink transfer roller side by side so that the inks at least touch or overlap at their boundaries and the inks mixed by means of additional acting on the outer surface of the ink transfer roller and suitable Verreibewalzen on the ink transfer roller become.

As a result, continuous color gradients are formed at the boundaries of the adjacent printing inks, which can be transferred to a printing substrate, for example with a printing form. The motifs printed in this way then have a corresponding color progression with continuous color transitions since, in this case, true mixing of the printing inks takes place.

Depending on the design of the color chambers used in this case, it is also possible to use a plurality of different printing inks, which makes it possible to realize, for example, a rainbow-like color progression.

In this case, a paint chamber of the known type, for example, a plurality of juxtaposed areas for receiving different inks, which are separated from each other by a partition. In each case, the respective regions have an opening directed towards a ink transfer roller, via which the respective printing ink is transferred to a specific region of the ink transfer roller.

It may be expedient to provide common doctor blade for all juxtaposed color chambers, whereby a homogeneous inking over the entire surface of the ink transfer roller can be achieved. In addition, a mixing zone can form at least directly at the doctor blade edges in the interior of the ink chamber at the boundaries of adjacent areas with different printing inks, whereby a first continuous mixing of adjacent different printing inks can take place.

The further mixing or trituration of the printing inks applied to the ink transfer roller is subsequently effected with one or more transfer rollers which act on the surface of the ink transfer roller and, for example, rub the printing inks with one another at different rotational speeds and / or additional movements in the direction of the roller axes and thus mix with one another.

The disadvantage here, however, is that when using color chambers of the known type, a color gradient can be generated substantially only in the direction of rotation of the ink transfer roller. A further disadvantage is that even when using a plurality of printing inks in a common ink chamber essentially only adjacent colors can be mixed together, so that a variable color mixing and in particular a different during operation color mixing is not possible.

If, for example, three different printing inks cyan, magenta and yellow are arranged side by side in a named inking chamber in the named order, then the respectively adjacent printing inks cyan and magenta or magenta and yellow can be mixed with one another on an inking roller, but not the printing inks cyan and yellow ,

Also, specially adapted ink chambers must be used with partitions, so that existing printing units can not be retrofitted without further.

Since in this type of printing, the mixing of the colors continuously increased and thus the mixing zone between said different printing inks on the platen is steadily widened and beyond the well-known return transport of ink from the ink roller in the ink chambers also already mixed colors in the ink chambers reaches, it is necessary to clean the pressure roller and the ink chambers continuously or at least at regular intervals, which can lead to a significant loss of color in the printing press. Color-gradient prints are therefore industrially preferred in the production of securities used, for example in rotary offset printing machines or gravure printing machines.

A disadvantage of the described known type of color gradient printing is further that due to the desired and necessary trimming of the printing inks on the printing roller and the continuously required cleaning of the printing roller, whereby a stable printing operation can be gewährleitstet, a number of additional components within the printing unit are required, such as Spreading rollers, cleaning devices, and their respective drives and controls. As a result, on the one hand, the complexity of the printing unit is increased and thus its operability is hampered and beyond additional space for the required additional components is required, which makes it difficult, for example, retrofitting a color gradient printing in an existing printing press or impossible.

By means of another known printing method, such as offset printing, flexographic printing or gravure printing such continuous color transitions can not be replicated, since these other methods have a specific Color impression reproduce by means of a subtractive overlay of several successively printed on a substrate color separations of a printed image, which is clearly visible at least in an enlarged representation of such a printed image. In these methods, it comes thus to a superposition of several colors, but not to the mixture.

The object of the invention is to provide a method and a device with which it is possible to avoid the mentioned disadvantages and to allow an optionally variable color gradient printing and, moreover, to limit the loss of color. The object of the invention is also to provide the ability to retrofit an existing printing unit with a gradient color.

The object is achieved according to the invention in that the inking device comprises a mixing chamber having at least two adjacent to each other parallel to the opening of the ink chamber mixing compartments each having at least two ink supplies for printing inks, wherein in the mixing compartments, the supplied printing inks are mixable and wherein the mixing compartments parallel to the opening The ink chamber arranged outlet openings, via which the ink chamber over the width of at least partially different mixed colors from the mixing chamber can be filled.

Here, a paint chamber in a known manner comprise two squeegee bars, to each of which a squeegee plate can be fastened, said opening between the edges of the squeegee plates is formed, can be transmitted by the color from the ink chamber to a ink transfer roller.

The object is further achieved in that in the aforementioned method, the ink chamber over the entire width of its opening with at least partially different mixed color from a mixing chamber is filled and the mixing chamber has a plurality, in particular over the width of the opening juxtaposed mixing compartments, in which the color is mixed in each case from at least two different colors supplied.

An essential core idea of the invention is not to apply the respective different printing inks to be mixed as usual in the prior art by means of juxtaposed paint chambers on a common Farbübertagswalze and to mix only on the lateral surface by means of a number of Verreibewalzen, but mixing already in a mixing chamber in which the inks are mixed in some areas and thus forms a color gradient before the ink reaches the ink chamber, so that the transferred to a ink transfer roller from the ink chamber ink already includes a color gradient.

For this purpose, said mixing chamber is provided with at least two mixing compartments, into which printing ink is supplied via at least two feeders, so that at least two different colors can be mixed in each of the mixing compartments. Of course, a mixing chamber can be charged with only a single color through the at least two feeders when a mixed color is not desired.

It is furthermore essential for the invention that the ink chamber is filled with mixed ink over its essentially entire width of the opening from the outlet openings of the mixing compartments of the mixing chamber, which are juxtaposed over the width of the opening. Thus, by the local arrangement of the outlet openings of the individual mixing compartments defined, where based on the width of the opening of the ink chamber, a certain ink mixture is filled.

If filling takes place during operation of the printing unit, then a rotating is formed in the ink chamber on the lateral surface of the ink transfer roller cylindrical ink roller, which has at least partially different colors or gradients over its width along its cylinder axis, in particular - as far as a further mixing in the ink chamber disregards - the range of different ink mixtures of the rotating ink roller at least substantially originate from respective mixing compartments of the mixing chamber. A predetermined by the arrangement of the outlet openings of the mixing compartments location dependence of the ink mixtures thus remains at least substantially preserved in the ink chamber.

Here, it is considered to be advantageous for the method and according to the invention for the device when the at least two mixing compartments of a mixing chamber are arranged side by side and in the side-by-side arrangement parallel to the width of the opening in the ink chamber. Thus, in this embodiment, the local juxtaposition of the mixing chambers and their respective outlets defines the location of the mixed colors in the forming rotating inking roller.

In principle, however, it is irrelevant for the implementation of the method according to the invention which arrangement the mixing compartments have, as far as at least the outlet openings of the mixing compartments adjacent to each other and in this juxtaposition parallel to the width of the opening, so that the mixed in the respective mixing compartments color a local assignment to the opening width receives and at least substantially retains the rotation in the ink chamber.

Depending on the number of mixing compartments used during this process and / or different printing inks, a plurality of color gradients can occur along the said cylinder axis of the rotating inking roller. The color distribution that exists in the rotating ink roller in the ink chamber is then transferred directly to the ink transfer roller.

To operate the device according to the invention, it may be provided that the inking device comprises a plurality of separately controllable ink supply devices, the ink supply means may be connected, for example, each with a different ink reservoir and in particular wherein the respective Farbzuführmenge is adjustable. In particular, printing inks, in particular different printing inks, can be conveyed into the mixing chamber and mixed there, in particular independently of one another, via the ink feed devices.

A mixing chamber can have a separate outlet opening for each mixing compartment or, in another embodiment, a common paint outlet opening which extends parallel to the opening or the width of the opening of the ink chamber and which is acted upon by the mixed ink from all outlet openings of the mixing compartments.

This has the particular advantage that color from the mixing chamber of the rotating ink roller of the ink chamber can be supplied by a flowing between the mixing chamber and the ink chamber color curtain of at least partially different mixed color, which extends over the entire width of the rotating ink roller.

Furthermore, the mixing chamber may also have a paint inlet opening which extends parallel to the opening of the ink chamber and into which all ink feeds open, the printing ink opening at least partially from the ink inlet opening into different mixing compartments.

It can be provided according to the invention that the mixing chamber has at a side opposite the mouth openings of the ink supply means said at least one outlet opening through which the mixed inks get into the ink chamber and so on the surface of a Farbübertragswalze.

In this case, the ink feeds of the mixing compartments may have different cross-sectional profiles at least in the area of their mouth openings, preferably over their entire extent. The ink feeds can also open in a mutually parallel arrangement side by side in the mixing chamber, wherein the respective mouth openings are arranged side by side in an array parallel to the opening of the ink chamber or substantially along a plane parallel to an axis of the ink transfer cylinder direction.

It may be provided that the respective orifices of the ink feeds substantially slit over a respective width, in particular with a height varying over its width, which may result, for example, a conical or triangular or a tapered cross-sectional shape, or a diamond shape or a lens shape. Depending on requirements, any other shapes for the mouth openings can be selected.

In this case, the mouth openings of the respective ink feeds may be arranged side by side so that they occupy a common extension direction, for example, parallel to the cylinder axis of the Farbübertagswalze It may result in a slot arrangement of a certain overall length, which may be summarized for example in a corresponding holder.

It may be provided that the sum of all slot heights along the entire direction of extent remains constant, which ensures that at a certain color feed rate determined for all ink supply means, the slot arrangement at any point of its total length can deliver the same total amount of ink.

The mouth openings of the ink feeds may also at least partly overlap or surround each other, in particular in such a way that in the area of the overlap / surroundings the sum of the heights of two overlapping openings is the same everywhere. The overlap / environment may also exist with regard to the entire ink feeds, that is, at least in some areas over the longitudinal extension of the feed channels. By such an overlap, first corresponding color mixing areas can also form during the ink feed. Also, the mouth opening of a feeder can act on at least two adjacent mixing compartments of a mixing chamber with the same color. All of these aforementioned or later to be named features of the feeders can be realized alone or in any combination.

It may also be provided according to the invention to arrange the orifices of different ink feeds viewed in the direction of rotation of the Farbübertagswalze one behind the other, especially if the mixing chamber is cylindrical and parallel to the axis of rotation of the ink transfer roller or the opening of the ink chamber. With this design then feeds can open at different angles in the mixing chamber and their compartments.

It may further be provided according to the invention, the ink feeders comprising channels (channels) individually or in groups on respective carriers, wherein the carrier are movable either synchronously or asynchronously to a rotational movement of a Farbübertragswalze, in particular along a plane parallel to an axis of the ink transfer cylinder movement.

In one embodiment, a plurality of mixing chambers, in which the different printing inks from the ink feed devices can be arranged, can also be arranged between the aforementioned ink feed devices with the ink feeds are mixed and which provide the blended inks for transfer to a color transfer roll.

Thus, the previously mentioned mixing chamber may be connected upstream of at least one further mixing chamber, in particular of the same type, and each ink feed of a mixing compartment of a subsequent mixing chamber may be connected to at least one other mixing compartment of a previous mixing chamber.

Thus, the previously mentioned mixing chamber to be mixed colors from at least one upstream mixing chamber are supplied, for which in one embodiment a plurality of mixing chambers can be arranged in series succession, in particular wherein a mixing compartment of a mixing chamber to be mixed colors from at least two mixing compartments of an upstream mixing chamber are supplied , For this purpose, the mixing compartments of two successive mixing chambers can be arranged offset to one another such that an outlet opening of a mixing compartment of an upstream mixing chamber opens into at least two mixing compartments of a subsequent mixing chamber.

Overall, it can be provided that the through the mixing compartments of a mixing chamber, e.g. pumped by pumping the feeders for all mixing compartments is the same, in particular wherein a mixing compartment of a mixing chamber, the colors to be mixed are supplied in different proportions. The different proportions may optionally be used in carrying out the process, e.g. changed by a higher-level control and in particular be adapted to the wishes.

A mixing of the different supplied printing inks in the mixing compartments can basically take place by any means, be it passive, for example by rigid or fixed flow elements or by active measures. For example, it may be provided that a mixing of the colors in a mixing compartment takes place by mixing bodies, which are moved in a mixing compartment by means of a common mixing shaft penetrating the rotating driven shaft. For example, in the mixing compartments loose mixing bodies, in particular balls may be arranged, which are moved by drivers on the shaft or on the mitrotierten with the shaft partitions, in particular wherein these mixing bodies perform an average directed movement in the direction of movement of the shaft, in particular wherein the respective balls of a mixing compartment remain in their movements in this. The mixing body or balls can consist of an abrasion-resistant and / or chemically inert material.

Thus, a mixing chamber, for example, at least in some areas be designed as a so-called ball mill or at least partially have Verreibewalzen. In these embodiments, it can preferably be provided that a mixing chamber is cylindrical, wherein the partitions can be mounted on a common driven and rotatably mounted centric shaft and preferably the mixing compartments are each filled with mixing elements. The moving partitions or the shaft can have carriers for the mixing elements.

If the mixing compartments are not separated from one another by means of partitions which are impermeable to ink, it is also possible to mix the colors of adjacent mixing compartments through partitions which are permeable to the paint between the mixing compartments.

The lateral surface of the cylinder of the mixing chamber can be slit in two places, in particular on two sides, and the slots can each form an inlet opening and an outlet opening. In this case, the mixing chamber is divided along its axis into a specific number of separate mixing compartments, which are in each case only in communication over a certain area of the inlet with the outlet openings of the ink feed and whereby the respective mixing compartments are each filled only with a certain proportion of a respective printing ink.

The respective portions of the ink which have penetrated into the respective mixing compartments via the inlet of the mixing chamber pass between the balls and are mixed due to the said irregular movements of the balls, whereby respective homogeneous mixed colors result. Characterized in that while the balls are largely prevented in their movement along the cylinder axis by remaining in their respective mixing compartment and also the mixing compartments are separated, for example by partitions, an undesirable Farbverschleppung along the cylinder axis of the mixing chamber is avoided. In addition, the mixed color is transported more or less straight through the mixing chamber, so that no unacceptable or undesirable mixing of adjacent areas occurs due to the short residence time of the mixed color in the mixing chamber.

It may be particularly advantageous when using a relatively small number of mixing compartments in a mixing chamber to arrange a second mixing chamber or optionally a plurality of mixing chambers of the same kind one behind the other, wherein subsequent mixing chambers, the mixed color is supplied from the preceding mixing chamber, in particular as it has already been described. In this case, a mixing compartment of a subsequent mixing chamber can be acted upon by the mixed colors from two mixing compartments of a preceding mixing chamber, in particular for which the inlet openings of the subsequent mixing chambers can each be arranged offset relative to the outlet openings of the preceding mixing chamber.

As a result, it is possible to further equalize a visible color difference of adjacent second mixed colors which may still be present at the outlet opening of the first mixing chamber, for example by dividing in each case half portions of adjacent second mixed colors of the first mixing chamber into one following mixing compartment of a second mixing chamber and there are mixed together in the manner described, so that at the last outlet openings of the last mixing chamber in each case emits a ready for printing mixed color.

It can also be provided that the mixing chambers following each other have the same or a different number of mixing compartments so as to produce a desired color gradient.

It can further be provided that the respective mixing compartments of a mixing chamber each have a different width in order to thereby produce a desired color gradient.

The finished mixed color thus produced subsequently passes into said ink chamber, which acts directly on the lateral surface of a ink transfer roller, for example an anilox roller, and is closed to the latter via corresponding doctor blade knives parallel to the roller axis. This ensures that no ink emerges uncontrolled and a defined color transfer is made possible on the ink transfer roller.

It can also be provided that the last mixing chamber be designed so that said doctor blade at least partially represent a part of the mixing chamber.

It may further be provided that the direction of movement of the ink transfer roller transferred to the finished mixed color rotational direction of the applied on the lateral surface of the ink transfer roller finished mixed color in the same direction or in opposite directions to a force exerted in the final mixing chamber on the finished mixed color direction of rotation of the mixing device.

It may be provided in a further embodiment that several slot arrangements are arranged one behind the other with the same or a different number of ink feed devices viewed in the production direction and their respective orifices act on a common mixing chamber, which results in the possibility of a desired color gradient during operation change or adapt, for example, by selectively switching on or off the corresponding inks from the corresponding ink supply devices in one of the slot arrangements and / or their color quantities are adjusted accordingly.

In all embodiments, it may also be provided to determine the diameter of the paint roller forming in the ink chamber during operation on the lateral surface of the ink transfer roller in each case in the region of the outlet openings of the ink supply devices and / or in the region of the mixing device by means of sensors, in particular at different positions and readjust by means of an appropriate control of the respective ink supply means, eg to change the amount of ink pumped.

It may further be provided to configure the respective ink delivery rates of the respective ink supply means controllable, for example, by their respective flow through adjustable pumps or valves are adjustable. This results in the possibility, as explained in more detail below, to influence the width of the color gradient zones.

If, for example, all the ink feed devices are set such that the respectively equal delivery quantity emerges from the respective discharge openings of the ink feeds, a locally different amount of ink will emerge corresponding to the local slot heights of the overlapping discharge openings. For example, the outlet openings have one each diamond-shaped cross-section, the respective ink delivery rates along the slot will have a substantially triangular distribution. In the overlapping area of adjacent outlet openings, two different printing inks thus come together, the percentage of which depends on the position along the slot arrangement and ranges from 0%: 100% to more than 50%: 50% to 100%: 0%.

Therefore, a first mixing of adjacent printing inks takes place at this position, at which time the printing inks are still essentially separated from one another.

Thus, according to the invention, this mixed color passes into a mixing device according to the invention, described above, according to the invention, in which this mixed color is mixed with one another in such a way that a homogeneous color mixture is established and, on the other hand, the mixing of this mixed color remains locally limited, whereby a complete mixing of adjacent Avoid areas of mixed color and associated destruction of a color gradient.

For this purpose, as mentioned, the mixing chamber may, for example, be designed substantially as a ball mill, wherein the mixing chamber has an inlet for receiving the mixed color and an outlet opening, for example opposite the inlet, through which the mixed mixed color emerges.

It can be provided in this case that the mixed color in the mixing chamber has only a short residence time and more or less straight is transported through the mixing chamber, whereby excessive and undesirable mixing of adjacent areas of the mixed color is avoided.

Embodiments of the invention will be described below. Show it:

FIG. 1:

a schematic side view of a first
invention
Execution of a paint application device

FIG. 2:

a schematic perspective view of a
Paint application device according to FIG. 1

FIG. 3:

a schematic side view of a second embodiment of a paint application device according to the invention

FIG. 4:

a schematic perspective view of a
Paint application device according to FIG. 3

FIG. 5:

a further schematic perspective view of a
Paint application device according to FIG. 3

FIG. 6:

a schematic page representation of a third
invention
Execution of a paint application device

A first embodiment of an inking device according to the invention for mixing a plurality of different printing inks to produce color gradients shows the FIGS. 1 and 2 ,

The inking device 2 is in this case, for example, substantially cylindrical and has at one point, in particular on one side of its lateral surface 21, an opening region 22 through which the different printing inks reach the interior of the mixing chamber 21 via respective feeds 51a. To illustrate the interior of the paint application device 2 is in this case in FIG. 2 the lateral surface 21 of the paint application device 2 partially removed.

The paint application device 2 further has at the location of a color transfer roller 1 point, in particular side on another opening portion 23 through which the finished mixed color on the lateral surface 1 b of Ink transfer roller 1 passes. In order to transmit a constant amount of ink on the lateral surface 1 b of the ink transfer roller 1, which is independent of the rotational speed of the rotating about an axis 1 a ink transfer roller, the ink transfer roller 1 is for example designed as an anilox roller, which depending on the number and execution of in its surface located wells has a specific ink receiving volume.

Furthermore, the inking device 2 has a working doctor blade 27 and a closing squeegee 28, as well as frontal covers, not shown, to seal the formed between the inking device 2 and the ink transfer roller 1 ink chamber 30, thereby preventing ink from the ink chamber 30 and the uncontrolled Paint application device emerges.

Due to the rotation of the ink transfer roller 1 in the direction 100 about its axis 1a, a paint roller 3 forms in operation, which rotates counter to the direction of rotation of the ink transfer roller 1 in the direction 101 and via which substantially the ink is transferred to the outer surface 1 b of the ink transfer roller 1 , To form a paint roller 3, it may be advantageous to attach the work doctor blade 27 at a distance to a side wall 26, so that a corresponding volume of a paint chamber 30 can be formed.

The work doctor blade 27 thereby excess ink from the surface 1 b of the ink transfer roller, such as an anilox roller from. The squeegee 28 seals the ink chamber 30 at the squeegee 27 opposite side of the ink chamber 30 so that no inks can escape from the ink chamber 30, for example, at a standstill of the printing press when no ink roller 3 forms and the ink chamber 30 more or less filled with ink.

According to the invention, the paint application device 2 has the opening area 22 mentioned, through which the different printing inks reach the interior of the paint application device 2, which is designed as a mixing chamber 201, for example via respective inlets 51a. The printing inks can be conveyed for example via respective pumps, not shown, from corresponding respective storage containers in the paint application device 2.

The inlet portions 51 b of the respective feeders 51 a can as in FIG. 2 shown having a different over their respective width (along the axial extent of the mixing chamber) height, which, for example, as in FIG. 2 shown can give a triangular cross-sectional shape. The respective inlet regions 51b are further arranged such that they overlap at least in the region of the opening region 22 so that, for example, over the entire inlet region 22 (in particular along the axial extent of the mixing chamber) an identical opening cross-section formed summarily from the respective adjacent inlet regions 51b results (in particular per unit length considered).

The interior of the paint application device 2 is subdivided, for example, along the longitudinal extension into individual mixing compartments 29, which are separated by respective partitions 24a and wherein the ink chamber is closed by end shields 24 to the outside. The respective dividing walls 24a are arranged and fastened, for example, on a common rotatably mounted shaft 25, so that they are also moved along their axis when the shaft 25 is rotated. It is further contemplated that the respective mixing compartments 29 has a respective quantity of balls 40, which are also set in motion upon rotation of the shaft 25 in the direction 102, for example via notches on the partitions 24a or shaft 25, not shown, and an im Perform means of rotational movement 102 rectified movement.

As a result of the average movement of the balls in the direction 102, an ink located in the respective mixing compartments receives a conveying direction in the direction 102 and arrives in the outlet region 23 from the inlet side 22 after a certain circulation distance. As a result of the balls, in addition to the average movement along the direction of rotation Performing 102 additional irregular movements, the different proportions of the different inks passing through the inlet portions 51 b in the respective mixing compartments 29 are effectively mixed together and result in each mixing compartment a different mixed color according to the mixing ratios. In order to prevent the balls falling out through the openings 22 and 23, it may be provided to close them with a grid or a perforated plate so that on the one hand the printing inks can pass substantially unhindered and on the other hand the balls are effectively retained in the interior of the mixing chamber ,

The partitions 24a can thereby as in FIG. 2 also shown perforated or in lamellar form, so as to allow a certain degree of color mixing of adjacent mixing compartments, the openings required for this purpose in the partitions 24a are so small that the balls located in the mixing compartments 40 can not pass through them.

The balls 40 may consist of known abrasion-resistant and chemically inert material, such as stainless steel, ceramic or the like, which prevents parts or abrasion of the balls get into the ink or that unwanted chemical reactions are triggered in the ink.

FIG. 3 schematically shows an inking device 200, which comprises a plurality of individual mixing chambers 201 202, 203 downstream of each other. Each of the mixing chambers 201, 202, 203 works according to the already described principle in that in respective mixing compartments 29, 39, 49 different proportions of printing inks or first or second mixed colors are further mixed together.

The individual mixing chambers 201, 202, 203 are in this case arranged relative to one another such that the respective outlet regions 43, 33 are connected to the associated inlet openings 32, 22 via respective connecting pieces 50. It may be provided to divide the connecting pieces 50 by means of partitions 50a into individual areas, wherein the number and arrangement of the subdivisions preferably corresponds to the number and arrangement of the mixing compartments of the respective upstream mixing chamber, so an uncontrolled and unwanted mixing of the respective first or second mixed colors after exiting the respective upstream mixing chamber to prevent.

FIG. 4 shows a schematic perspective view of a paint application device according to the invention accordingly FIG. 3 , wherein the cylindrical outer surface 41 of the uppermost mixing chamber 203 is partially omitted for showing the internal structure. As already described de respective mixing chambers 201, 202, 203 respective shafts 25, 35, 45, on each of which a certain number of partitions 44a and respective covers 44 are attached. Upon rotation of the respective shaft 25, 35, 45 in the respective direction 102, 103, 104, the dividing walls 24a, 34a, 44a are respectively moved and the balls 40 located in the respective mixing compartments 29, 39, 49 are also not shown via drivers emotional. This has the effect that the color components which have reached the respective mixing compartments are effectively mixed with one another and the mixed color is simultaneously transported from the respective inlet openings 22, 32, 42 to the respective outlet openings 23, 33, 43. The direction of rotation can be chosen so that the ink undergoes the longest possible residence time within the respective mixing compartment in order to achieve optimal mixing.

FIG. 5 shows a further schematic representation according to FIG. 3 , wherein in addition to the clarification of the internal structure of the ink chamber additionally the lateral surface 31 of the mixing chamber 202 is omitted. According to the invention, the respective mixing compartments 39, 49 are arranged, for example, relative to each other such that a first mixing color passes from a first mixing chamber 203 through a connecting piece 50 provided with partitions 50a, for example proportionally in two adjacent mixing compartments 39 of the subsequent mixing chamber, whereby it is possible still present color differences to further equalize adjacent first mixed colors.

It can also be provided to select the number of mixing compartments of the subsequent mixing chambers 202, 201 each higher than the number of mixing compartments of the preceding mixing chamber, for example, each twice as high, whereby on the one hand a continuously finer mixing of adjacent mixed colors takes place and on the other At any time controlled and homogeneous color gradient along the longitudinal axis of the ink roller 3 and thus on the outer surface 1 b of the ink transfer roller 1 can be generated.

FIG. 6 shows a third embodiment of an inking device 2 according to the invention with a mixing chamber 201, the paint application device 2 in this embodiment, two inlet openings 22, 22a, through which zonewise different inks can get into the mixing chamber 201. For this purpose, respective feeds 51a, 52a are attached to the inlet openings 22, 22a, via which different printing inks, for example, are conveyed respectively via unillustrated pumps from corresponding storage containers into the paint application device 2.

The respective feeds 51a, 52a can, as described, each have different cross-sectional shapes and also along a common extension direction parallel to the longitudinal axis of the ink chamber 2 or to the cylinder axis 1 a of the ink transfer cylinder 1 overlap. By arranging further feeds 52a, which are arranged substantially parallel to the first feeds 51a, the possibility arises optionally to introduce additional different printing inks into the mixing chamber 201 and thus to easily produce further mixing colors which would otherwise not be producible.

If, for example, the printing inks cyan, magenta, yellow are introduced into the mixing chamber 201 via first juxtaposed feeds 51a, the transition mixed colors can be generated between cyan and magenta and between magenta and yellow, but not between cyan and yellow, since these inks do not coexist be introduced into the mixing chamber 201. If, on the other hand, the printing inks in the order of magenta, yellow, cyan are optionally introduced into the mixing chamber 201 via a parallel feed 52a, alternatively the transition mixed colors can be produced between magenta and yellow and between yellow and cyan.

If in each case different ink feeds of the feeders 51a and 52b are combined by introducing in each case printing inks into the mixing chamber 201, optionally further mixed inks can also be produced during operation of the printing press, for example by simultaneous feeds 51a, 52a lying parallel or overlapping one another the mixing chamber 201 is filled with different printing inks.

It is self-evident that the number of respective feeders 51a, 52a and the respective cross-sectional shapes 51b, 52b of the feeders 51a, 52a and their arrangement with each other and each other may be the same or different as needed.

With regard to all embodiments, it should be noted that the technical features mentioned in connection with one embodiment can be used not only in the specific embodiment, but also in the other embodiments. All disclosed technical features of this invention description are to be classified as essential to the invention and arbitrarily combined or used alone.

Claims (15)

Ink application device (2) for applying printing ink to a ink transfer roller (1) comprising a paint chamber (30) with an opening extending across the width thereof, from which ink can be applied to the ink transfer roller (1) and which comprises a mixing chamber (21) at least two juxtaposed parallel to the opening of the ink chamber (30) mixing compartments (29) each having at least two ink feeds (51a) for printing inks, wherein in the mixing compartments (29) the supplied printing inks are mixable and wherein the mixing compartments (29) parallel to the opening the ink chamber (30) arranged outlet openings, via which the ink chamber (30) over its width with at least partially different mixed colors from the mixing chamber (21) can be filled, characterized in that a mixing chamber (21) is cylindrical and the mixing compartments are separated by partitions, wherein the partitions (24 a) on a he common driven and rotatably mounted centric shaft (25) are attached. Paint application device according to claim 1, characterized in that the mixing chamber (21) has a paint outlet opening (23) which extends parallel to the opening of the ink chamber (30) and which is acted upon by paint from all outlet openings of the mixing compartments (29) and / or the Mixing chamber (21) has a paint inlet opening (22) which extends parallel to the opening of the ink chamber (30) and in which all ink feeds (51 a) open, wherein the printing inks from the ink inlet opening (22) in different mixing compartments (29) open , Paint application device according to one of the preceding claims, characterized in that the mixing chamber (21) at least one further mixing chamber (31,41) of the same kind is connected upstream and each ink supply of a mixing compartment (39) of a subsequent mixing chamber (31) with at least another mixing compartment (49) of a previous mixing chamber (41) is connected. Paint application device according to one of the preceding claims, characterized in that the ink feeds (51a) of the mixing compartments (29) have different cross-sectional profiles at least in the area of their mouth openings (22). Paint application device according to claim 4, characterized in that the mouth openings (22) of the ink feeds (51a) at least partially overlap such that in the region of the overlap, the sum of the heights of overlapping openings is the same everywhere. Paint application device according to one of the preceding claims, characterized in that the mixing compartments (29) are respectively filled with mixing elements (40) made of an abrasion-resistant and / or chemically inert material, wherein the partitions (24a) and / or the shaft (25) Have driver for the mixing elements (40). A method of inking a ink transfer roller (1) with ink from a paint chamber (30), wherein the ink is applied through an opening of the ink chamber (30) on the ink transfer roller (1) and the ink chamber (30) over the entire width of its opening with at least area mixed differently color from a mixing chamber (21) is filled and the mixing chamber (21) has a plurality of juxtaposed across the width of the opening mixing compartments (29), in which the color is mixed in each case from at least two different colors supplied, characterized in that the mixing of the paint takes place in a cylindrical mixing chamber (2), in which the mixing compartments are separated by partitions (24a) which are mounted on a common driven and rotatably mounted centric shaft (25) and are moved in rotation therewith. A method according to claim 7, characterized in that in the ink chamber (2) on the lateral surface (1 b) of the ink transfer roller (1) forms a rotating cylindrical ink roller (3) over its width along its cylinder axis at least partially different colors or gradients having. Method according to one of the preceding claims 7 or 8, characterized in that the mixing chamber (21) to be mixed colors are supplied from at least one upstream mixing chamber, wherein the mixing chambers (21, 31, 41) are arranged in series one after the other and a mixing compartment ( 29, 39) of a mixing chamber (21, 31) to be mixed colors from at least two mixing compartments (39, 49) of an upstream mixing chamber (31, 41) are supplied Method according to one of the preceding claims 7 to 9, characterized in that the by the mixing compartments (29, 39, 49) of a mixing chamber (21, 31, 41) conveyed amount of ink for all mixing compartments (29, 39, 49) is the same, a mixing compartment (29, 39, 49) of a mixing chamber (21, 31, 41), the colors to be mixed are supplied in different proportions. Method according to one of the preceding claims 7 to 10, characterized in that a color mixture in the supply of the colors in a mixing compartment (29, 39, 49) is effected in that the mouth openings of at least two adjacent feeds (51 a) overlap at least partially and / or at least partially surrounding each other. Method according to one of the preceding claims 7 to 11, characterized in that the supply of the different colors by juxtaposed along the width of the mixing chamber (21) into these opening feeds (51 a) takes place. Method according to one of the preceding claims 7 to 12, characterized in that a mixing of the colors of adjacent Mixing compartments (29) by permeable partition walls (24a) between the mixing compartments (29). A method according to claim 7 to 13, characterized in that a mixing of the colors in a mixing compartment (29) by in the mixing compartments (29) arranged loose mixing body (40), wherein the mixing body by means of drivers on the shaft (25) or on the with the shaft (25) mitrotierten partitions (24a) are moved and wherein said mixing body (40) perform an average directed movement in the direction of movement of the shaft (25). Method according to one of the preceding claims 7 to 14, characterized in that color from the mixing chamber (2) of the rotating ink roller (3) of the ink chamber (30) is supplied by a between the mixing chamber (21) and the ink chamber (30) flowing color curtain of at least partially different mixed color, which extends over the entire width of the rotating ink roller (3).

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