EP1118708B1 - Coating device - Google Patents

Abstract

The applicator (10a) for coating the surface of a moving fiber web with a liquid or paste coating medium (28) has a distribution channel (26a) and the flow openings (34) into the equalizing channel (32a) are at the function unit (12a), which is in a swing mounting at or anchored to the carrier structure (14). The distribution channel (26a) has a longitudinal and pref. rectangular cross section. A run-off gutter (56) is under the function unit (12a). A swing drive, with a motor-driven spindle lift, swings the function unit (12a) in relation to the carrier structure (14), and at least one limit stop restricts the swing movement. A further function unit (18a) is mounted to the carrier structure (14) or a fitting (20) at it, as a doctor (42a) to give a dosing and/or equalizing action on the applied coating layer (54) of the coating medium (28) on the web surface (U). The doctor unit (18a), function unit (12a) and the applicator chamber (44a) together form a short dwell time applicator (SDTA). Or the function units (12a,18a) together with an applicator jet form a free stream jet applicator. The function unit (12a) is exchangeable with one cover which forms the limit wall section (31) to define the equalizing chamber (32a), fitted to the carrier structure (14). The replacement function unit has a number of separate applicator jets from the distribution channel, across (Q) the web width, to deliver the coating medium (28) to the running web surface (U). The same structure can be used for an indirect coating action on the web surface (U).

Description

The invention relates to a device for applying a liquid or pasty application medium to a running substrate, wherein the substrate for direct application, the surface of a material web, in particular of paper or cardboard, and indirect application, the surface of a transfer element, preferably a transfer roller, which the application medium is then transferred to the surface of the material web, wherein the application device comprises, comprises a functional unit which is pivotally hinged to a parent support structure or a part attached thereto.

Such application devices with pivotable functional units are known, for example, from DE 44 32 177 A1 and EP 0 846 804 A1, which disclose both free-jet nozzle application devices. In these two application devices of the distribution channel is formed in the parent support structure or attached to this part. Accordingly, the functional unit serves only to limit the compensation chamber and to arrange or form one of the nozzle lips of the delivery nozzles of these free-jet nozzle applicators. For maintenance or cleaning of the known application devices is initially the parent support structure of a counter-roller swung off, the surface either forms the running ground or supports the web. Subsequently, the functional unit is pivoted away from the parent supporting structure or the part attached to it, in order to allow an inspection of the compensation chamber. Since the person carrying out the maintenance or cleaning is usually located on the side of the support structure facing away from the functional unit, unfavorable conditions are present in particular for the visual inspection of the transfer openings between the distribution channel and the compensation chamber.

The last statement also applies to applicators described in DE-U-9471321, US-A-5599393 and EP-A-0781608.

For further prior art, reference should be made to DE 44 14 949 A1, which discloses a short dwell time applicator (SDTA) for whose maintenance or cleaning the above applies as well.

In contrast, it is an object of the present invention to provide an applicator device which is easier to maintain or clean.

This object is achieved by an applicator device of the type mentioned above, at softer the distribution channel is provided on the functional unit, which is articulated pivotably to a parent support structure or attached to the functional unit part. The distribution channel contains a plurality of transfer openings or individual nozzles. This surprisingly simple measure ensures that the chamber of the functional unit having the transfer openings or individual nozzles, and in particular the transfer openings or individual nozzles themselves, is fully exposed to the view of the operating or maintenance person after the functional unit has been swiveled away from the support structure. Thus, the passage direction of the transfer openings or the individual nozzles is substantially in the direction of the maintenance person, so that they can easily check whether one or more of the transfer openings or individual nozzles are clogged. This was not possible in the prior art applicators discussed above due to a merely grazing view of the transfer openings.

If the distribution channel has an elongated, preferably substantially rectangular, cross-sectional area, then the application device can be pivoted closer to the mating surface (for example surface of the mating roll) due to this space-saving construction of the distribution channel during operation without the return of excess application medium to becomes tight. This offers greater freedom in the choice of the operating angle of the applicator device according to the invention.

As is known per se from the prior art, below the functional unit, a drainage channel can be arranged, in which the excess application medium draining from the substrate is collected and returned from there into a coating medium reservoir. This gutter has the further advantage in the arrangement according to the invention that it can absorb any leakage currents from the distribution channel and the compensation chamber and therefore protects the entire system from contamination due to such leakage currents.

To increase the reliability of the applicator device according to the invention is further proposed that the functional unit can be anchored to the parent support structure or attached to this part.

In principle, it is possible that the maintenance person pivots the functional unit for maintenance or cleaning by hand from the parent support structure. However, the inspection of the application device according to the invention can be further simplified in that a pivot drive device is provided for pivoting the functional unit relative to the parent support structure. The pivoting drive device may preferably engage at one of the lateral ends of the applicator, ie on the drive side and / or the leader side of the applicator. As a pivot drive device For example, a motor-driven Spindelhubwerk into consideration. To protect the mating roll may further be provided at least one end stop for limiting the pivotal movement of the functional unit.

In addition to the above-mentioned functional unit can be arranged in a further development of the invention to the parent support structure or attached to this part another functional unit.

This further functional unit may comprise, for example, a squeegee device for dosing or / and leveling the layer of application medium applied to the substrate, for example a doctor blade or a squeegee rod with a smooth or profiled surface. Furthermore, it can be provided that the further functional unit together with the one functional unit forms the application chamber of a commissioned unit with a short contact time or that the further functional unit together with the one functional unit forms the dispensing nozzle of a free jet nozzle applicator. Finally, it is also possible for the one functional unit to be exchangeable for a functional unit which merely forms a cover of the compensation chamber bounding wall parts of the parent support structure or of the part attached thereto or which forms a distribution channel for supplying application medium and a plurality of transversely of the Subsurface distributed arranged individual nozzles for dispensing the application medium to the ground comprises.

According to the above discussion, it is a further great advantage of the device according to the invention that it can be converted easily in a simple way, whereby it can be converted not only into different types of application devices, but also to a simple doctor device.

Fig. 1

eine schematische Seitenschnittansicht einer ersten Ausführungsform einer erfindungsgemäßen Auftragsvorrichtung im Betriebszustand;

Fig. 2

die in Fig. 1 dargestellte Auftragsvorrichtung in Wartungsstellung; und

Fig.3-5

Ansichten ähnlich Fig. 1 weiterer Vorrichtungen zum Auftragen von Auftragsmedium auf einen laufenden Untergrund bzw. zum Dosieren und/oder Egalisieren einer auf den Untergrund aufgebrachten Schicht von Augtragsmedium.

The invention will be explained in more detail below with reference to embodiments with reference to the accompanying drawings. It shows:

Fig. 1

a schematic side sectional view of a first embodiment of an applicator device according to the invention in the operating state;

Fig. 2

the application device shown in Figure 1 in the maintenance position. and

Fig.3-5

Views similar to FIG. 1 of further devices for applying application medium to a running substrate or for dosing and / or leveling a layer of eye-wearing medium applied to the substrate.

In Fig. 1, an applicator device according to the invention is generally designated 10a. It serves to apply a layer 54 of application medium 28 to a substrate U moving in the direction of the arrow L, for example a material web, in particular of paper or cardboard.

In the embodiment shown, the application device 10a is designed as a short-dwell time applicator (SDTA). It comprises a first functional unit 12a, which is pivotally connected to a supporting beam 14 by means of a hinge 16, and a second functional unit 18a, which is arranged on a part 20 connected to the supporting beam 14.

The first functional unit 12a comprises a base plate 22a, by means of which it is articulated to the support beam 14 via the hinge 16. On the side facing away from the support beam 14 of the base plate 22a, a manifold 24a is connected to the base plate 22a, wherein the manifold 24a and the base plate 22a together define a distribution channel 26a, through which the application medium 28 in the transverse direction Q of the substrate U is supplied. The support bar 14 facing surface 30a of the base plate 22a and a portion 31 of the surface of the support beam 14 together define a compensation chamber 32a, which communicates with the distribution channel 26a via a plurality of distributed in the transverse direction Q of the substrate U arranged transfer openings 34a in combination. The compensation chamber 32a is sealed in the embodiment of FIG. 1 down by a equipped with a sealing element 36a sealing lug 38a. At the side edges of the compensation chamber 32a arranged in front of and behind the plane of the drawing according to FIG. 1, respective sealing arrangements (not shown) are provided.

Attached to the upper end of the base plate 22a in FIG. 1 is an attachment element 40a which, together with a doctor device 42a, delimits the application chamber 44a of the SDTA application device 10a. The Doctor blade device 42a, which is part of the second functional unit 18a, comprises in the illustrated embodiment a doctor blade 46a with a smooth or profiled surface, which is received in a doctor bed 48a. The doctor bed 48a is fastened to the part 20 connected to the support beam 14 via a blade element 50a and a roughly double-headed positioning device 52. Furthermore, a further adjusting device 58 is provided between the part 20 arranged on the support beam 14 and the doctor device 42a, by means of which the layer thickness of the application layer 54 can be influenced, preferably both in the longitudinal direction (longitudinal profiling) and in the transverse direction (transverse profiling).

In the application chamber 44a, the application medium 28 is associated with the substrate U moving in the direction of the arrow L, i. in the case of direct application to the surface of a material web, in particular of paper or cardboard, or in the case of indirect application to the surface of a transfer element, in particular a transfer roll, which then applies the layer 54 of application medium 28 deposited thereon in the direction of travel L downstream of the application device 10a to the Material web transfers.

Further, a gutter 56 is provided, which is attached to the support beam 14 and serves to absorb by means of the doctor device 42a from the substrate U abgerakeltes, excess application medium 28 'and in a (not shown) Auftragmediumvorrat for re-supply through the distribution channel 26a due.

In order to keep the dimensions of the compensation chamber 32a as constant as possible in order operation, individual spacers 60a are provided on the base plate 22a, which are additionally anchored via an anchoring device 62a, such as bolts, on the support beam 14 positively to unintentional lifting the Spacer 60a and pivoting of the base plate 22a and the entire first functional unit 12a to be reliably prevented by the support beam 14.

It should also be added that, in order to bring about the pivoting movement of the first functional unit 12a relative to the support beam 14, an actuating device 64, which is only roughly schematically indicated in FIG. 2, is provided, as well as an end stop 66 which limits the pivotal movement of the first functional unit 12a.

The applicator 10a described above is advantageous in several ways:

If, for example, to perform cleaning or maintenance of the support beam 14 is pivoted from the substrate U, and after loosening the anchoring device 62a, the first functional unit 1 2a pivoted from the support beam 14, as shown in Fig. 2, so the view (dash-dotted arrow B) the operator or maintenance person not only the compensation space boundary surface 30a of the base plate 22a of the first functional unit 12a, but above all the transfer passages 34a between the distribution channel 26a and the compensation space 32a presented in a way that allows in a simple manner, the Crossover passes 34a then visually check whether one or more of them are clogged. This considerably facilitates the cleaning or maintenance of the application device 10a.

As a further advantage, it should be mentioned that any leakage application medium emerging from the distribution channel 26a or the compensation chamber 32a, such as the scraped-off excess application medium 28 ', is likewise collected by the collecting channel 56. Thus, contamination of the application device 10a and the surrounding system parts in a simple manner reliably prevented.

Finally, as a further advantage, it should also be mentioned that the device according to the invention can be easily converted into a different type of application device or another type of device for the treatment of the substrate U by exchanging the two functional units 12a and 18a, as described below Example of Figures 3 to 5 will be explained in more detail:

FIG. 3 shows a further embodiment of an application device according to the invention, which essentially corresponds to the application device according to FIGS. 1 and 2. Therefore, in Fig. 3 analogous parts are provided with the same reference numerals as in Fig. 1, but supplemented by the lower case letter "b" instead of "a". Moreover, the embodiment according to FIG. 3 will be described below only to the extent that it differs from the embodiment according to FIGS. 1 and 2, to the description of which reference is hereby expressly made.

In contrast to the application device 10a according to FIGS. 1 and 2, the application device 10b according to FIG. 3 is designed as a free-jet nozzle applicator. For this purpose, the attachment element 40b attached to the base plate 22b of the first functional unit 12b is designed as a nozzle lip 70b on its free end facing the substrate U. On the other hand, the second functional unit 18b comprises a nozzle lip element 72b, which is fastened via a blade element 50b and the adjusting device 52 to the part 20 connected to the support beam 14. The die lips 70b and 72b together delimit a nozzle channel 74b, through which the application medium 28 is released in the free jet as a coating layer 54 to the substrate U.

The conversion from the SDTA application device 10a according to FIGS. 1 and 2 to the free-jet nozzle application device 10b according to FIG. 3 can be carried out by simply exchanging the SDTA functional units 12a and 18a with the free-jet functional units 12b and 18b. This is it for one thing required to swing the first SDTA functional unit 12a off the support beam 14 and unhook it from the hinge 16, instead of hooking the first free-jet functional unit 12b into the hinge 16, then pivoting against the support beam and anchoring it at 62b. On the other hand, only the squeegee device 18a needs to be detached from the element 20 fastened to the support beam 14 and replaced by the die lip assembly 18b after release of the adjusting device 52.

It should also be pointed out that the first SDTA functional unit 1 2a and the first free-jet functional unit 12b differ in their construction only with regard to the shape of the elements 40a or 40b.

FIG. 4 shows a further embodiment of an application device according to the invention, which essentially corresponds to the application devices explained above. Therefore, in Fig. 4 analogous parts are provided with the same reference numerals as in Fig. 1, but supplemented by the lower case letter "c" instead of "a". Moreover, the embodiment according to FIG. 4 will be described below only to the extent that it differs from the above-described embodiments, to the description of which expressly reference is hereby made.

In the embodiment according to FIG. 4, the application device 10c is designed as a long-acting applicator (LDTA). In this case, the first functional unit 12b comprises a single-nozzle applicator, in which the application medium 28 is applied to the substrate U as a spray jet by means of a plurality of individual nozzles 80c arranged side by side in the transverse direction Q on the distributor tube 24c. The second functional unit 18c arranged downstream of the first functional unit 12c in the direction of travel L of the substrate U is in turn in the exemplary embodiment shown in FIG. 4 as a doctoring device 42c, which completes the coating applied to the substrate U layer 54 of coating medium and equalized.

In contrast to the exemplary embodiments explained above, the base plate 22c of the first functional unit 12c has no perforations. However, it is designed as a cover plate for the SDTA application device 10a and the free jet nozzle application device 10b, the compensation chamber 32a and 32b bounding side of the support beam 14 surface portions 31 and protects them from contamination by drying application medium 28th

According to the exemplary embodiment illustrated in FIG. 5, the device 10d can also serve merely for metering or / and leveling a layer 54 of application medium 28 which has been applied to the substrate U upstream of the device 10d in the direction L of the substrate U. In this case, the first functional unit 12d comprises only one cover plate 22d, while the second functional unit 18d in turn comprises a doctor device 42d.

Claims (14)

1. Device (10a; 10b, 10c, 10d) for applying a liquid or pasty application medium (28) to a moving substrate (U),
   the substrate, in the case of direct application, being the surface of a material web, in particular of paper or board, and, in the case of indirect application, being the surface of a transfer element, preferably a transfer roll, which then transfers the application medium to the surface of the material web,
   the application device comprising:

   a functional unit (12a; 12b, 12c, 12d) which is attached such that it can be pivoted to a superior load-bearing structure (14) or to a part fixed to the latter, a distribution duct (26a, 26c) being provided on the functional unit (12a; 12b, 12c) and the distribution duct (26a, 26c) containing a plurality of overflow openings (34a) or individual nozzles (80c).
2. Application device according to Claim 1, characterized in that the distribution duct (26a, 26c) has an elongated, preferably substantially rectangular, cross-sectional area.
3. Application device according to Claim 1 or 2, characterized in that a drainage channel (56) is arranged underneath the functional unit (12a; 12b, 12c).
4. Application device according to one of Claims 1 to 3, characterized in that the functional unit (12a; 12b, 12c) can be anchored on the superior load-bearing structure (14) or the part fixed to the latter.
5. Application device according to one of Claims 1 to 4, characterized in that a pivoting drive device (64) is provided in order to pivot the functional unit (12a, b, c) relative to the superior load-bearing structure (14).
6. Application device according to Claim 5, characterized in that the pivoting drive device (64) comprises a motor-driven spindle lifting mechanism.
7. Application device according to one of Claims 1 to 6, characterized in that at least one end stop (66) is provided in order to limit the pivoting movement of the functional unit (12a; 12b).
8. Application device according to one of Claims 1 to 7, characterized in that a further functional unit (18a; 18b) is arranged on the superior load-bearing structure or the part (20) fixed to the latter.
9. Application device according to Claim 8, characterized in that the further functional unit (18a) comprises a doctor device (42a) for metering and/or equalizing the layer (54) of application medium (28) applied to the substrate (U).
10. Application device according to Claim 8 or 9, characterized in that the further functional unit (18a), together with the one functional unit (12a), forms the application chamber (44a) of an applicator having a short action time.
11. Application device according to Claim 8, characterized in that the further functional unit (18b), together with the one functional unit (12b), forms the discharge nozzle (74b) of a free jet nozzle applicator.
12. Application device according to one of Claims 1 to 11, characterized in that the one functional unit (12a, 12b) can be replaced by a functional unit (12d) which merely forms a cover for the wall parts (31) of the superior load-bearing structure (14) or the part fixed to the latter which delimit the equalization chamber (32a).
13. Application device according to one of Claims 1 to 12, characterized in that the one functional unit (12a, 12b) can be replaced by a functional unit (12c) which comprises a vertical duct (26c) for supplying application medium (28) and a plurality of individual nozzles (80c) arranged distributed in the transverse direction (Q) of the substrate (U) in order to discharge the application medium (28) onto the substrate (U).
14. Application device according to Claim 10 and 11, characterized in that the functional unit (12a, 12b) has an equalization chamber (32a, 32b) which is connected to the distribution duct (26a, 26b) via the plurality of overflow openings (34a) arranged distributed in the transverse direction (Q) of the substrate (U), the equalization chamber (32a, 32b) being formed by a first boundary wall (31) of the superior load-bearing structure (14) and a second boundary wall (30a) of the functional unit (12a, 12b), and the two boundary walls (31, 30a) forming the equalization chamber (32a, 32b).

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