EP1348549B1 - Coating roller with a sleeve - Google Patents

Abstract

A typical coating machine has a rotating drum (1) with a perforated surface (6), dipping into a bath (12) of coating fluid (10). The fluid flows through the perforations (30) into the interior of the drum. A fluid film is formed inside (38) and outside (18) the drum. Films are lifted out of the bath. The outer portion of the outside film may drain back into the bath. The outer film is carried round until it approaches (24) the downwardly moving fabric strip (14). In the contact region (16) it adheres to the strip (22) and is carried away downward.

Description

The present invention relates to an applicator roll having a roll shell according to the preamble of claim 1.

Furthermore, the present invention relates to a method for coating material webs according to the preamble of claim 10.

In web-fed rotary printing, for example in web-fed rotary offset printing, a web of material is unwound from a supply roll in a roll changer, vertically or horizontally fed for printing by a plurality of printing units arranged in sequence, then passed through a dryer, for example a hot air dryer, for drying and finally for cooling the heated in the dryer material web passed over cooling rollers of a chill roll stand. Subsequently, the web can be cut into a folder to signatures and folded, it being possible to supply the generated signatures further to a distribution system. The material web is usually printed by the printing units on both sides and in multiple colors, the use of dampening solution being necessary in conventional offset printing, which is why the material web first has to be dried before subsequent processing and consequently has to be cooled.

Prior art chill roll stands typically include a plurality of chill rolls traversed by a cooling medium, the chute being passed on a meandering path through the chill roll stand and around the chill rolls.

It is also known to apply by means of an applicator roll, a liquid coating agent, for example silicone oil emulsion over the entire surface of the web, wherein the applicator roll may be disposed within the chill roll stand. The coating of the printed material web with the silicone oil-water emulsion in the form of a thin film prevents smearing of the products in the turning bar area or in the folding unit of the printing press. Furthermore, the laying of the under the silicone layer lying ink on deflecting elements, for example on turning bars prevented.

From the DE 197 43 741 A1 a system is known for coating carrier webs with a coating agent which comprises application rollers which receive or scoop the coating agent, in particular silicone oil emulsion, from a respective dip pan and whose lateral surfaces, which are wetted by the coating agent, are in contact with the carrier web.

The surface quality of the respective applicator roll is not described in detail, so it can be assumed that it is usually smooth and closed surfaces.

In addition, in the US 3,923,936 describes a roller which has regularly distributed on its surface and relatively small openings. The roller described can be used either to transfer a liquid to a surface or to receive a liquid from a surface. The roll may further be formed as a dipping roll together with a dip pan or as a hollow roll, the interior of which is acted upon by a liquid or a negative pressure. Furthermore, the roll can be used for dewatering, for example, paper, wherein a paper web is passed through a gap between the described roller and another counter-pressure roller. In this case, the liquid absorbed by the roller described by the capillary action of the openings is pressed in a further gap to a further counter-pressure roller from the sponge-like surface of the described roller.

The absorbent surface thus absorbs liquid to either transfer it to the web or pick it up from the web. Between these two possibilities will be in the US 3,923,936 strictly distinguished.

Furthermore, the describes DE 29 34 005 A1 a device for removing liquid from running strip material, wherein a hollow roll on the surface of the strip material, for example, cold-rolled, high-speed metal belts, rolls and wherein and the surface of the hollow roller is covered with at least one layer of absorbent material. Furthermore, the hollow roll has a perforated jacket below the absorbent material, the holes of which are provided for the passage of absorbed liquid from the at least one layer of absorbent material in the negative pressure inside the hollow cylinder.

However, the described hollow surface with absorbent surface does not serve to apply a liquid to the strip material.

The DE 199 57 453 C1 discloses a method for applying high-viscosity ink in an offset printing machine, wherein a hollow roller is used, the surface of which is formed by a net-like structure through which the guided into the interior of the hollow cylinder ink to the outside and thus transferred to another roller can. Excess and untransferred color is carried along a complete revolution of the roller and pushed back into the network structure in the contact gap between the net roller and the subsequently arranged roller by the contact pressure between the two rollers.

However, the disclosed roller has no surface for applying the paint. Instead, the surface is substantially reduced as much as possible in order to provide by means of the net-like structure a large number of openings through which the paint application or transfer takes place.

From the US 4,188,882 Finally, a moistening device for offset printing machines is known, wherein the dampening solution is absorbed by a fountain roller in a dip tank and transferred to the net-like surface of another roller, which is acted upon from the inside with blown air, that the transferred dampening solution from the net-like surface in the direction of moisturizing element is sprayed.

When applying a liquid by means of an applicator roll on, for example, a material web or a downstream additional roll, there is the problem that can accumulate excess liquid in the form of a reservoir in the inlet pocket between the applicator roll and the web or the other roller.

When coating a material web, there is also the problem that the material web may have reduced contact with the applicator roll during transport, for example due to fluttering of the material web, and in such cases excess liquid from the formed reservoir in the inlet gusset through the gap between the material web and the applicator roll can pass and thus can form a coating on the material web in uneven distribution. These irregularities in the coating are recognizable in the final product, for example a printed product, and thus unacceptably degrade its quality.

It is therefore an object of the present invention to provide an applicator roll with which a uniform application, transfer or coating is possible.

It is another object of the present invention to provide an applicator roll which prevents the accumulation of excess liquid.

Also, an object of the present invention may be seen to provide an alternative applicator roll or an alternative transfer roll to the prior art rolls.

It is a further object of the present invention to provide a method of coating webs of material whereby the accumulation of excess liquid is avoided.

It is also an object of the present invention, the problems described when applying or transferring a liquid or when coating with a Liquid to fix or at least reduce.

These objects are achieved by the features of claim 1 and / or claim 10. Further features of the invention are contained in the subclaims.

An applicator roll according to the invention with a roll shell, the outer shell surface of the roll shell receiving and at least partially transferring a liquid, is characterized in that the roll shell has a perforation through which excess liquid is discharged into the interior of the applicator roll.

Advantageously, a uniform application and / or transfer of liquid can be achieved by the applicator roll according to the invention, wherein the outer surface of the roll shell of the applicator roll receives the liquid and at least partially transmits, but also avoided simultaneously that too much and thus excess by the applicator roll Liquid is absorbed and transferred.

According to the invention, such excess liquid is replaced by a perforation, i. H. discharged through openings in the roll shell in the interior of the applicator roll.

• die Aufnahme und Übertragung der Flüssigkeit und das Abführen überschüssiger Flüssigkeit in den Innenraum der Auftragswalze. Es ist auf diese Weise vorteilhaft möglich, mit einer einzigen und konstruktiv einfach gestalteten Auftragswalze einen gleichmäßigen Auftrag/Übertrag bzw. eine gleichmäßige Beschichtung zu erreichen.

The application roller according to the invention thus has a lateral surface, which according to the invention performs two functions:

• the absorption and transfer of the liquid and the removal of excess liquid in the interior of the applicator roll. It is advantageously possible in this way to achieve a uniform application / transfer or a uniform coating with a single and structurally simple designed application roller.

Furthermore, irregularities on the element to be coated, for example a material web, which are advantageously produced by excess liquid or by excess coating agent can be avoided and thereby whose quality is significantly increased.

In a further embodiment of the invention, the perforation of the outer surface of the roll shell of the applicator roll excess liquid, in particular water, dampening solution, silicone oil-water emulsion or paint, which in an inlet pocket between the applicator roll and a downstream rotating element, in particular a roller or a Cylinder, or an endless continuous element, in particular a material or paper web is located in the interior of the applicator roll.

In this way, advantageously, accumulation of liquid in the inlet gusset can be prevented or liquid already accumulated in the inlet gusset can be broken down again. The interior of the applicator roll can furthermore be designed as a hollow space and thus the applicator roll as a hollow roll, so that the liquid passing through the perforation into the interior can be dissipated without hindrance.

It is also possible that the applicator roll scoops the liquid by means of the outer surface of the roll shell from a dip pan or storage pan or receives from an upstream rotating element, in particular a roller, receives or transferred.

The interaction of the applicator roll with a dip or storage trough, from which the serving for coating liquid is used, continues to the uniform application of the liquid, in particular interruptions in the liquid supply can be avoided because the applicator roll is always sufficiently wetted with liquid. However, it is also conceivable that the upstream rotating element is designed as a dipping roller and transfers the liquid to the applicator roll in a transfer nip.

Furthermore, the surface of the applicator roll can also be sprayed with the liquid or the supply of the liquid can be carried out by a chamber doctor blade, which is in operative connection with the roller.

Furthermore, it can be provided that the liquid discharged into the interior of the applicator roll is at least partially returned to the immersion trough through the perforation of the lateral surface of the roll shell of the applicator roll. The liquid level in the dip pan and the liquid level inside the applicator roll are at the same level, as caused by the perforation, the dip pan and the interior of the applicator roll form a system of communicating tubes. During rotation of the applicator roll, however, the liquid level in the interior of the roll can drop and at the same time sufficiently small opening ratio (ratio opening area to total area), for example below 10%, the liquid level can also decrease almost completely.

The coating agent or the liquid discharged through the perforation into the interior of the applicator roll can thus advantageously also flow again through the perforation into the storage trough and again serve for wetting the outer jacket surface of the applicator roll.

The perforation of the applicator roll advantageously eliminates the need for further means for discharging the liquid discharged into the interior space, for example in the axial direction through the rollers of the applicator roll, that is to say that such means can advantageously be dispensed with, which leads to a further cost reduction. and labor reduction in operating and maintaining the applicator roll leads.

However, it is also conceivable that the interior of the applicator roll with a, for example, light, negative pressure is applied to receive the liquid through the perforation, for example, from the reservoir in the inlet gusset. In this case, for example, a pump can be used with which the suction power is adjustable through the perforation of the roll shell.

To prevent the suction of liquid, which is located in the lower region, and thus at the same level as the liquid level in the immersion tank, can The interior of the applicator roll may also be divided into, for example, two chambers, wherein only the upper chamber is subjected to negative pressure. In this case, the upper chamber can act in particular that section of the applicator roll with negative pressure, which forms the inlet gusset. This makes it possible in an advantageous manner to increase the discharge of excess liquid through the perforation.

In a further embodiment of the applicator roll according to the invention, the perforation can be formed in such a way that each axial effective region of the applicator roll has at least one perforation opening.

The axial effective range of the applicator roll is to be understood as meaning any axial section of the applicator roll which is designed for applying or transferring liquid. For example, the end portions of the applicator roll may not belong to the effective area of the applicator roll. By providing at least one perforation opening in each axial effective region of the applicator roll, that is to say at least one perforation opening in the outer circumferential surface at an arbitrary point in the circumferential direction within the effective region, it is advantageously ensured that both the up or transfer of the liquid and the absorption of excess liquid by the applicator roll in the axial direction is uniform. In this way, in particular visible irregularities, for example banding, on a printed product can be avoided.

Furthermore, the intake of excess liquid, for example, from an inlet gusset, is performed in the axial direction with high uniformity, so that, for example, when using highly viscous liquids accumulated liquid seen in the axial direction is evenly degraded.

Furthermore, the perforation can be designed as line perforation in such a way that circumferentially and axially offset perforation openings cover partially common axial areas.

A trained as line perforation perforation in the roll shell of the applicator roll, with individual lines or slots of the perforation partially overlap together axial areas, additionally serves the uniform application or transfer of liquid and thus the uniform coating to be coated good.

It is particularly advantageous, for example, to design the application roller in such a way that the perforation openings have a length of less than 50 mm or 8 mm to 50 mm and a width of less than 1 mm or 0.1 mm to 1 mm, for example 0, 25 mm. The perforation openings can be cut, for example by means of a laser device in the roll shell of the applicator roll.

An applicator roll according to the invention can also have a drive, in particular a separate drive or motor.

In a further embodiment of the invention, the applicator roll also iridescent, d. H. be driven in an oscillating manner in the axial direction.

An applicator roll according to the invention may preferably be arranged in front of the first and / or in front of the second chill roll of a chill roll stand. For example, an applicator roll of the present invention may apply silicone oil-water emulsion to a paper web in a portion of the vertically top-to-bottom web path between the first and second chill rolls of a chill roll stand. The application roller can be arranged on the side of the material or paper web, on which the second cooling roller is located, so that the emulsion is applied to the surface of the web before it is passed over the subsequent cooling roller and a greasing, depositing or Condensation of ink on the chill roll is avoided.

It may be provided in a further embodiment of the invention to form the interior of the applicator roll such that it has an increased absorbency, for example, a spongy material or a sponge body in the interior of the Order roller be arranged. As a result, liquid is sucked inwards from the perforation openings in an advantageous manner, so that there is no undesirable high liquid application or uneven application. Especially in connection with circular perforation openings, the use of absorbent material is advantageous.

It can further be provided that a chill roll stand, in particular a chill roll stand integrated directly into a dryer or immediately downstream of a dryer, is characterized by an inventive application roll as described above.

Moreover, a printing press, in particular a web-fed rotary printing press or web-fed rotary offset printing press, may be characterized by an applicator roll as described above or by a chill roll stand having such an applicator roll or by a dryer having such an applicator roll.

A method according to the invention for coating webs of material, in particular webs in web-fed rotary printing or web-fed rotary offset printing, wherein a liquid, in particular silicone oil emulsion, is applied to the web by means of the outer jacket surface of the roll shell of an applicator roll is characterized by the fact that excess liquid, in particular such liquid, which is located in an inlet gusset between the applicator roll and the web, is discharged by means of a perforation in the roll shell in the interior of the applicator roll.

The advantages stated above in connection with the application roller according to the invention described above also result in carrying out the method according to the invention for coating material webs, in particular a uniform coating of the material web can be brought about in an advantageous manner and the accumulation or build-up of excess liquid is reduced or even avoided become.

The removal of the excess liquid through the perforation takes place, for example by the capillary action of the perforation openings, by the force acting on the liquid gravity, by the pressure of the liquid due to the height of the built-up reservoir, by the contact pressure in the gap between applicator roll and subsequent roller or web or by the suction effect with the interior of the applicator roll in Actually connected pump or vacuum source.

The invention will be described below with reference to the drawings based on preferred embodiments.

Figur 1

eine Auftragswalze nach dem Stand der Technik, wobei eine Materialbahn vertikal von unten nach oben geführt und die Auftragswalze im Gleichlauf betrieben wird;

Figur 2

eine Auftragswalze nach dem Stand der Technik, wobei eine Materialbahn vertikal von unten nach oben geführt und die Auftragswalze im Gegenlauf betrieben wird;

Figur 3

eine Auftragswalze nach dem Stand der Technik, wobei eine Materialbahn vertikal von oben nach unten geführt und die Auftragswalze im Gegenlauf betrieben wird;

Figur 4

eine Auftragswalze nach dem Stand der Technik, wobei eine Materialbahn vertikal von oben nach unten geführt und die Auftragswalze im Gleichlauf betrieben wird;

Figur 5

eine Auftragswalze nach dem Stand der Technik, wobei eine Materialbahn horizontal und die Auftragswalze im Gleichlauf betrieben wird;

Figur 6

eine Auftragswalze nach dem Stand der Technik, wobei eine Materialbahn horizontal und die Auftragswalze im Gegenlauf betrieben wird;

Figur 7

zwei nacheinander angeordnete Auftragswalzen nach dem Stand der Technik, wobei eine Papierbahn horizontal geführt, eine Auftragswalze im Gleichlauf und eine Auftragswalze im Gegenlauf betrieben wird;

Figur 8

eine erfindungsgemäße Auftragswalze, wobei eine Papierbahn vertikal von oben nach unten geführt und die Auftragswalze im Gleichlauf betrieben wird;

Figur 9

eine erfindungsgemäße Auftragswalze, wobei eine Materialbahn vertikal von oben nach unten und die Auftragswalze im Gegenlauf betrieben wird;

Figur 10

eine erfindungsgemäße Auftragswalze, wobei eine Materialbahn horizontal und die Auftragswalze im Gegenlauf betrieben wird;

Figur 11

Walzenmantel einer erfindungsgemäßen Auftragswalze, die eine Perforation aufweist;

Figur 12

Ausschnitt der Mantelfläche des Walzenmantels einer erfindungsgemäßen Auftragswalze;

Figur 13

eine erfindungsgemäße perforierte Auftragswalze in Verbindung mit einer nachfolgenden Walze;

Figur 14

eine erfindungsgemäße perforierte Auftragswalze in Verbindung mit einer vorgeordneten und einer nachgeordneten Walze;

Figur 15

eine erfindungsgemäße perforierte Auftragswalze mit im Innenraum der Auftragswalze angeordneten Abführelement.

In the drawings show:

FIG. 1

an applicator roll according to the prior art, wherein a web is guided vertically from bottom to top and the applicator roll is operated in synchronism;

FIG. 2

an applicator roll according to the prior art, wherein a web is guided vertically from bottom to top and the applicator roll is operated in reverse;

FIG. 3

an applicator roll according to the prior art, wherein a material web is guided vertically from top to bottom and the applicator roll is operated in reverse;

FIG. 4

an applicator roll according to the prior art, wherein a material web is guided vertically from top to bottom and the applicator roll is operated in synchronism;

FIG. 5

an applicator roll according to the prior art, wherein a web is horizontal and the applicator roll is operated in synchronism;

FIG. 6

an applicator roll according to the prior art, wherein a material web horizontal and the applicator roll is operated in reverse;

FIG. 7

two successively arranged applicator rolls according to the prior art, wherein a paper web guided horizontally, an applicator roll in synchronism and an applicator roll is operated in the opposite direction;

FIG. 8

an applicator roll according to the invention, wherein a paper web is guided vertically from top to bottom and the applicator roll is operated in synchronism;

FIG. 9

an applicator roll according to the invention, wherein a material web is operated vertically from top to bottom and the applicator roll in the opposite direction;

FIG. 10

an applicator roll according to the invention, wherein a material web is operated horizontally and the applicator roll in the opposite direction;

FIG. 11

Roll shell of an applicator roll according to the invention, which has a perforation;

FIG. 12

Section of the lateral surface of the roll shell of an applicator roll according to the invention;

FIG. 13

a perforated applicator roll according to the invention in connection with a subsequent roller;

FIG. 14

a perforated applicator roll according to the invention in conjunction with an upstream and a downstream roll;

FIG. 15

a perforated applicator roll according to the invention with arranged in the interior of the applicator discharge element.

In the drawings, corresponding features are provided with the same reference numerals.

Figures 1 to 7 show prior art applicator rolls, showing the various configurations, that is, different web path directions and different applicator roll directions of rotation. The various configurations shown lead to different ratios with respect to the transport path of the liquid to be applied, which will be described in more detail below.

In FIGS. 1 to 10, in each case at least one application roller 1 is shown, which has an axis of rotation 2, a direction of rotation 4, a roller shell 6 and an outer circumferential surface 8. By the rotation of the applicator roll 1, this draws a liquid 10, for example a silicone oil-water emulsion, from an immersion trough 12 by means of the outer jacket surface 8. The outer jacket surface 8 of the applicator roll 1 wetted with the liquid rolls on the surface of a transported material web 14 and transfers the liquid 10 drawn from the immersion trough 12 in the form of a closed liquid film onto the surface of the material web 14.

In Figure 1, the case is shown that the web 14 is guided vertically from bottom to top and the applicator roll 1 is operated in synchronism.

The term "synchronism" is intended to indicate that the material web 14 and the applicator roll 1 have surface speeds that are rectilinear in the contact region 16 between one side of the surface of the material web 14 and the outer jacket surface 8 of the applicator roll 1. The amount of surface velocities of the material web 14 and the applicator roll In contrast to this, however, the term "mating" is intended to indicate that the velocities of the surface velocities of the material web 14 and the outer lateral surface 8 in the contact region 16 are opposite to one another, whereby the amounts may also have different values.

As can be seen from FIG. 1, a liquid film 18, which extends from the surface of the liquid 10 stored in the immersion trough to the contact region 16, forms on the outer circumferential surface 8 of the roll mantle 6. This liquid film 18 is entrained together with the lateral surface 8 in accordance with the rotation of the application roller 1 and effects a coating of the material web 14 with a liquid film 20. Excess liquid which does not pass the contact region 16 and thus does not contribute to the formation of the liquid film 20, runs in the form Thus, in this configuration of web guide direction and applicator roll rotation, there is no problem with accumulating excess liquid on the applicator roll or in the infeed nip 24 between the applicator roll 1 and the web of material 14.

In this case, a liquid film 18 is also formed on the surface 8 of the roll mantle 6 of the applicator roll 1, which is transferred in the inlet gusset 24 as liquid film 22 to the material web 14. Since in this case the applicator roll 1 is operated in the opposite direction, the material web 14 takes the transported in the inlet pocket 14 liquid in the form of the liquid film 22 completely, so there is no accumulation of excess liquid in the inlet pocket 24. Furthermore, too much scooped liquid 10 in the form of a liquid film 20 is returned to the dip tank 12, whereby this liquid film 20 runs on the liquid film 18 under the influence of gravity.

FIG. 3 shows the relationships with respect to FIG. 1, in the case where the direction of rotation 4 of the applicator roll 1 is maintained, but the running direction of the paper web 14 is reversed. Also in this case, there is no build up or accumulation of excess liquid in the inlet gusset 24 between the applicator roll 1 and the material web 14th

FIG. 4 shows a coater-driven applicator roll 1, but with respect to FIG. 1, the transport direction of the material web 14 extends in the vertical direction from top to bottom. As can be seen from FIG. 4, a reservoir 26 of excess liquid, which is fed by the liquid film 18, forms in the inlet gusset 24 in this case. As a result of the transport of the material web 14, there are fluctuations in the contact pressure between the material web 14 and the application roller 1 in the contact region 16, so that an additional amount of liquid 28 is transferred to the material web 14 from the reservoir 26 at least over time. This, for example, formed as a strip coating the web 14 significantly reduces the quality of a printed product produced.

As shown in Figure 5 and Figure 7, the problem of accumulating liquid in the inlet gusset 24 between the applicator roll 1 and the web 14 may occur even with horizontal web guide.

FIG. 5 shows an applicator roll 1 which is operated in synchronism and which rotates at a rotational speed in such a way that more liquid is transferred from the immersion trough 12 into the inlet gusset 24 than is removed through the contact region 16 in the form of the coating liquid film 20 becomes. The reservoir 26 could be avoided or degraded in this case by a lower rotational speed of the roller 1, but it may be possible that at a reduced rotational speed of the liquid film 20 on the material web 14 does not have the necessary thickness or, for example, irregular, so that the skilled person would refrain from a reduction in the rotational speed.

FIG. 6 shows the applicator roll 1 from FIG. 5 operated in the opposite direction, as a result of which liquid does not accumulate in the inlet gusset 24.

The right-hand roll shown in FIG. 7 is operated in the opposite direction in accordance with the roll shown in FIG. 6, but revolves at a higher rotational speed, so that it turns in In this case, the formation of a reservoir 26 in the inlet pocket 24 comes.

FIG. 8 shows an applicator roll 1 according to the invention with a roll shell 6 and an outer jacket surface 8, the outer jacket surface 8 of the roll shell 6 receiving a liquid film 18 and transferring it at least partially in the form of a liquid film 22 to a material web 14 in a contact region 16. According to the invention, the roll mantle 6 has a perforation 30, through which excess liquid, which could accumulate in the inlet gusset 24 as a reservoir 26 as shown in FIG. 4, is discharged into the interior 32 of the applicator roll 1 and returns there, for example in the form of a liquid film 34 for stored liquid 10 is guided in the dip tank 12.

Since the stored liquid 10 forms a system of communicating tubes in the immersion trough 12 outside the applicator roll 1 and within the applicator roll 1, the liquid level inside and outside the applicator roll is equalized and, if appropriate, the excess liquid is returned to the immersion trough 12.

As a result of the contact pressure prevailing in the contact region 16 between the application roller 1 and the material web 14, excess liquid is forced through the perforation openings of the perforation 30 into the interior or into the interior 32 of the application roller 1.

In the embodiment of the applicator roll 1 according to the invention shown in FIG. 8, a liquid film 20 also forms on the liquid film 18 entrained with the applicator roll 1, which runs back into the immersion trough 12 as a result of gravity.

Prevention of the formation of a reservoir 26 in the inlet gusset 24 (see Figure 4) can be achieved, for example, by suitable choice of perforation, that is, by the number and configuration of the openings on the surface of the roller 1 or by the rotational speed of the applicator roll 1 influenced or even controlled become. The rotational speed can also be specified by a control unit.

As can also be seen from FIG. 8, the inner circumferential surface 36 of the roll mantle 6 also carries a liquid film 38 from the liquid reservoir 10, but this liquid film 38 does not reach the outer surface, that is, without reaching the outer mantle surface 8 of the roll mantle 6. redirected with the applicator roll 1 and again supplied to the stored liquid 10. At usual maximum rotational frequencies of the applicator roll 1 of about 50 to 200 revolutions per minute, it can not come to a passage of the liquid through the perforation 30 from the inside out as a result of the force generated by the rotation of the applicator roll 1 flying force.

It should be mentioned here that advantageously the rotational frequency of the application roller is chosen such that its surface speed assumes a predetermined percentage of the material web speed, d. H. at speed changes of the material web, for example when starting the machine, the rotational frequency of the applicator roll changes accordingly. This percentage is usually in the range of 1% to 10%, for example between 2% and 5% or, for example, below about 3%. An advantageous application roller in conjunction with a vertical web guide can, for example, have a maximum rotational frequency of less than 100, in particular 75, revolutions per minute.

FIG. 9 shows the application roller 1 from FIG. 8, but now in the opposite direction to the material web 14. Also in this case, the surface 8 of the roller shell 6 carries a sufficiently strong liquid film 18 from the storage tank 12, so that a coating liquid film 22 of the desired thickness is provided the material web 14 can be formed. It is thus easily possible to run the applicator roll 1 in synchronism or in the opposite direction and possibly to switch between two operating states.

It should also be noted that the problem of color build-up on the applicator roll in the situations shown in Figures 2, 3 and 6, since in the contact region 16, the web 14th and the surface of the applicator roll 1 are not coated with liquid. In contrast, this problem is solved by the use of the applicator roller according to the invention in the situation shown in Figure 9, since the roller surface 8 of the applicator roller 1 is wetted by the capillary de perforation 42.

Another disturbing effect of the applicator rolls according to the prior art will be described here. If a conventional applicator roll is operated in the opposite direction, more liquid is transferred than in synchronous operation, since the liquid must pass through the contact area during synchronization.

On the other hand, an applicator roll according to the invention can also produce sufficient liquid, for example, in synchronism. B transferred to a web, since in this mode after passing the contact area liquid can be pulled out of the perforation opening. The operator can therefore choose as well as the synchronous operation as the mating mode and thus prevent the buildup of color on the applicator roll in an advantageous manner.

FIG. 10 also shows how the use of an applicator roller 1 according to the invention can prevent a reservoir 24 from forming in the inlet gusset 26 (see FIG. 7, right-hand roller) in the case of horizontal web guidance. Excess liquid is discharged in the region of the inlet gusset 24 or the contact area 16 through the perforation 30 into the interior 32 of the applicator roll 1 and fed there in the form of a liquid film the liquid circuit in the liquid reservoir 10 in the dip tank 12 again. An advantageous application roller in conjunction with a horizontal web guide may, for example, have a diameter between 30 mm and 50 mm, in particular approximately 38 mm, and a maximum rotational frequency between 150 and 200 revolutions per minute.

Unlike in FIG. 10, the applicator roll 1 according to the invention can also be advantageously operated in synchronism with horizontal web stirring (compare FIG. 7, left-hand roll).

FIG. 11 shows the roll mantle 6 of an applicator roll 1 according to the invention with a rotation axis 2, the perforation of the roll mantle being shown in a region 40. The perforation is formed as a line perforation, wherein the perforation openings are arranged substantially parallel to the axis of rotation and offset axially and in the circumferential direction.

FIG. 11 also shows that the axial active region 46, indicated by the two dashed lines, has at least one perforation opening. Although not shown in FIG. 11, an applicator roll according to the invention may have a perforation on the entire acting surface of the roll shell, as shown in region 40, and thus be formed such that each axial effective region 46, ie, each axial region, provides for the transfer of liquid is, at least one perforation 43 has.

Figure 12 shows the area 40 in an enlarged and schematic representation, wherein the staggered arrangement of the perforation openings 42, both in the axial direction Y and in the circumferential direction X can be seen. The individual perforation openings 42a to 42d each have a length L and a width B, wherein the length L extends in the axial direction and the width B in the circumferential direction. It can also be seen from FIG. 12 that the perforation openings 42a to 42d cover a common axial region C. In the event that cover all end portions of the perforation openings 42 in this way, it can be ensured that there are no axial areas of the applicator roll 1, which do not have at least one perforation opening or at least a portion of a perforation opening and thus a banding by not discharged excess Prevent liquid.

As shown in Figure 12, the two perforations 42b and 42d have an axial offset or offset of DY and a circumferential offset or offset of DX. The surface of the applicator roll 1 between the Perforations 42 is according to the invention sufficiently large that a sufficient scooping of liquid and the recording and transferring this liquid is ensured in the desired and necessary amount. For example, it may be advantageously provided to choose the ratio of the total area of the openings 42 to the total surface of the applicator roll 1 in the range between 1% and 50%. To reduce or prevent reservoirs 26, a ratio of less than 5%, in particular less than 3% or, in particular, about 1%, is advantageously selected. In order to achieve a rewetting of a dried material web with the application roller 1, in addition to the application of, for example, silicone oil emulsion, a ratio of more than about 10% is advantageously selected.

In addition to a line perforation, any other type of perforation is conceivable, for example a perforated perforation, wherein the perforation openings can advantageously have a diameter of 1 mm to 10 mm, in particular about 2 mm or about 4 mm.

FIG. 13 further shows that the application roller 1 can also transfer the liquid film 18 to a downstream roller 48 and can be advantageously used to prevent the formation of a liquid reservoir in the inlet gusset 24 between the application roller 1 and the downstream roller 48. Thus, it is possible, for example, to use the applicator roll according to the invention also in an inking or dampening train within a printing or dampening unit of a printing press.

As shown in FIG. 14, the applicator roll 1 according to the invention can also be inserted between an upstream roll 50 and a downstream roll 48 for transferring a liquid from the upstream roll 50 to the downstream roll 48. In this case, the applicator roller 1 according to the invention, which in this case may also be referred to as a transfer roller, prevents the formation of a reservoir in the inlet gusset 24 between the downstream roller 48 and the applicator roller 1 and the emergence of a reservoir in the inlet gusset 52 between the upstream Roller 50 and the applicator roll 1. Excess liquid, for example water, paint, dampening solution or silicone oil emulsion, is discharged through the perforation 30 in the roll shell 6 of the applicator roll 1 into the interior 32 of the applicator roll 1.

The excess liquid can then (as shown in FIG. 15) be guided in the axial direction out of the application roller 1 or, as shown in FIG. 14, through the perforation as a result of gravity, to a collection region 54, for example in the form of a bent metal sheet There, in particular by means of a pump 56 to the liquid reservoir 10 are fed again.

In contrast, FIG. 15 reveals that the quantity of liquid discharged through the perforation 30 into the interior 32 of the applicator roll 1 can also be collected there by a receiving means 58 which, for example, bears against the inner circumferential surface 36 of the applicator roll 1. The liquid 60 contained in the receiving means 58 can now, for example, in the axial direction from the interior 32 of the applicator roll, for example, through the end portions or the bearing journals of the applicator roll 1, dissipated and in particular a liquid circuit can be fed again.

LIST OF REFERENCE NUMBERS

1

applicator roll

2

axis of rotation

4

direction of rotation

6

roll shell

8th

outer jacket surface

10

liquid

12

dip trough

14

web

16

contact area

18

liquid film

20

liquid film

22

liquid film

24

inlet pocket

26

reservoir

28

interrupted liquid film

30

perforation

32

inner space

34

liquid film

36

inner jacket surface

38

liquid film

40

Area

42

perforation

42a - d

perforation

46

axial effective range

48

Subordinate roller

50

upstream roller

52

inlet pocket

54

catch area

56

pump

58

receiving means

60

liquid

X

circumferentially

Y

axial direction

L

Length of the perforation opening

B

Width of the perforation opening

C

common axial area

DX

Offset in the circumferential direction

DY

Offset in the axial direction

Claims (11)

1. Form roller having a roller sleeve (6), wherein the outer sleeve surface (8) of the roller sleeve (6) picks up and at least partially transfers a liquid (10, 18, 20),
   characterized in
   that the roller sleeve (6) has a perforation (30, 42, 42a-d), through which excess liquid (26) is carried away into the interior (32) of the form roller (1).
2. Form roller according to claim 1,
   characterized in
   that the perforation (30, 42, 42a-d) carries away into the interior (32) of the form roller (1) excess liquid (26), in particular water, fountain solution, silicone oil emulsion or ink that is situated in a feed gap (24) between the form roller (1) and a downstream rotating element (48), in particular a roller or a cylinder, or an element (14), in particular a material web or a paper web, that is running continuously away.
3. Form roller according to claim 1 or 2,
   characterized in
   that the form roller (1) by means of the outer sleeve surface (8) of the roller sleeve (6) draws the
   liquid (10) from a dip tank (12) or receives the liquid (10) from an upstream rotating element (50), in particular a roller.
4. Form roller according to claim 3,
   characterized in
   that the liquid (34) carried away into the interior (32) of the form roller (1) is fed at least partially through the perforation (30, 42, 42a-d) to the dip tank (12).
5. Form roller according to one of the preceding claims,
   characterized in
   that the perforation (30, 42, 42a-d) is designed in such a way that each axial effective region (46) of the form roller (1) has at least one perforation opening (42, 42a-d) .
6. Form roller according to one of the preceding claims,
   characterized in
   that the perforation (30, 42, 42a-d) is designed in such a way or is designed in such a way as a line perforation (42, 42a-d) that perforation openings (42, 42a-d) arranged offset in peripheral direction (X) and in axial direction (Y) partially overlap common axial regions (C).
7. Form roller according to claim 6,
   characterized in
   that the perforation openings (30, 42, 42a-d) have a length (L) of less than 50 mm and a width (B) of less than 1 mm.
8. Form roller according to one of the preceding claims,
   characterized in
   that the interior of the form roller (1) comprises absorbent material, in particular a sponge-like material or a sponge body.
9. Cooling roller stand, in particular a cooling roller stand integrated into a drier or disposed downstream of a drier,
   characterized by
   at least one form roller (1) according to one of claims 1 to 8.
10. Printing press, in particular a web-fed printing press or web-fed offset printing press,
    characterized by
    at least one form roller (1) according to one of claims 1 to 8 or by a cooling roller stand having at least one form roller (1) according to one of claims 1 to 8 or by a drier, in particular a hot-air drier, having an integrated or immediately downstream cooling roller stand that has at least one form roller (1) according to one of claims 1 to 8.
11. Method of coating material webs (14), in particular paper webs in web-fed printing or web-fed offset printing, wherein by means of the outer sleeve surface (8) of the roller sleeve (6) of a form roller (1) a liquid (10, 18, 20), in particular silicone oil emulsion, is applied onto the material web (14),
    characterized by the method step:

    carry away excess liquid (26), in particular liquid that is situated in a feed gap (24) between the form roller (1) and the material web (14), into the interior (32) of the form roller (1) by means of a perforation (30, 42, 42a-d) in the roller sleeve (6).

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