EP2055832A2 - Device for regulating the width of a coating to be fixed with a curtain painting machine - Google Patents

Abstract

The device for regulating the coating width of a coating applied with a curtain coating machine, comprises an application head (1) comprising an application medium chamber (2) and a slit (3) for delivering a liquid to pasty application medium to a continuous paper, cardboard or other fibrous material web, and a limiting element (4) insertable at both lateral ends of the delivery slit. The limitation element consists of a flexible plate, which is inserted from downside into the delivery slit and is buckled during the insertion in a zig-zag manner. The device for regulating the coating width of a coating applied with a curtain coating machine, comprises an application head (1) comprising an application medium chamber (2) and a slit (3) for delivering a liquid to pasty application medium to a continuous paper, cardboard or other fibrous material web, and a limiting element (4) insertable at both lateral ends of the delivery slit. The limitation element consists of a flexible plate, which is inserted from downside into the delivery slit and is buckled during the insertion in a zig-zag manner, where the thickness of the flexible plate is smaller than the width of the opening of the delivery slit. A part of the limitation element is kept with a flexible cover (5) of the boundary region of the delivery slit at the exterior surface of the application head. The flexible plate of the limitation element consists of a plastic material and is alternatively knocked several times and inserted on the lower edge of the delivery slit. The cover is manufactured from the flexible plate. The edge part of the limitation element and the edge part of the cover are stuck together and are kept at the exterior surface of the application head. A mounting plate (6) is intended for holding the edge part of the limitation element and the cover at the exterior surface of the application head. The mounting plate comprises a pressure hose, which is positioned in the inner side of a groove intended horizontally at both sides in width direction of the exterior surface of the application head. The mounting plate comprises another pressure hose on the exterior side of a pressure plate. The edge part of the limitation element and the edge part of the cover are enclosed between the groove and the pressure hose. The pressure hose is filled with air, so that it expands.

Description

The present invention relates to a device for regulating the coating width of a coating to be applied by a curtain coater, comprising an applicator head with an application medium chamber and a dispensing slot extending from the application medium chamber for dispensing a liquid to pasty application medium to a running paper, board or other Fibrous web, wherein at both lateral ends or edges of the discharge slot in each case a limiting element in the discharge slot can be inserted

Coated paper, such as printing paper, catalog paper, etc., pressure-sensitive paper, thermal paper, etc., is produced in an online or offline coater by placing on a die-forming web (starting material) a liquid to pasty application medium, e.g. Coating color is applied and then dried.

In most cases, so-called blade coaters, in which the method of replenishment was used, were used as coaters. In this process, coating medium (e.g., size, thickness, coating color) was applied in excess to the web and then metered with a doctor blade member such as a rod, blade or air knife, that is, brought to the desired coating weight.

When painting with this method of re-dosing, there is the problem that by the fluid pressure during application of the medium on the web, by the pressure of the squeegee much color penetrates into the web and that the maintenance costs are high due to the wear of the squeegee element.

Therefore, curtain coating machines have been increasingly used in recent years.

In this type of application, the application medium is applied in the form of a curtain from an applicator head from above onto the underlying moving web a curtain layer of paint.

Curtain coaters have been used for a long time in the production of photo paper for photographs and so on.

In the paper industry these machines have not been used in practice because of the significantly higher machine speeds where there is a risk of air getting into the medium curtain at these high speeds. This makes the curtain unstable, i. it can tear off and / or bubbles can mix in the application medium.

Recently, solutions for the paper industry have been increasingly developed, with which a use of the Florstrechnikstechnik, i. The curtain coating is now possible as a safe technique.

Curtain coaters lead, unlike conventional coating machines, no additional metering and therefore have no wear parts in the form of doctor elements. This has the advantage that the maintenance is simple, the amount of coating can be easily applied with high precision and the operability is good. In addition, the applied contour line (Contour Coat) shows an improvement in the surface quality.

From practice a curtain coater is known. This should be the FIG. 3 demonstrate. Shown is a used in the relevant known curtain coater applicator head in section, which in the FIG. 3 denoted by 1. This application head contains an application medium chamber 2 extending in the width direction of the application head 1 into which the application medium, for example coating color, is filled. The application head 1 is assembled from two parts 1a and 1b so that the part 1a has the application medium chamber 2 and the part 1b does not. The application medium chamber 2 is directed downward in an open, located between opposite die lips 1c and 1d discharge slot 3. The nozzle lip 1d is adjustable to adjust the width of the discharge slot 3, wherein the opening or the slot width is 0.3 to 0.5 mm. The nozzle lip 1d is attached to the lower edge of the applicator head part 1b by means of several profile regulating bolts 1 e.

A set consisting of the profile regulating bolt 1e or upper pressure bolt 1e, a lower pressure bolt 1g and a middle tension bolt 1f is attached at a distance of about 50 mm in the width direction of the application head. Characterized in that the opening or width of the discharge slot 3 is finely regulated in the width direction, the profile of the color curtain is regulated.

It should be mentioned that in a coater the width of the fibrous web to be spread (in particular paper web) is changed relatively frequently. It is necessary, according to the width of the web, the coating width or Ausströmit width of the slot 3 to change. In order to change this opening width of the slot 3, in each case a limiting element are introduced from below and clamped from the outside, so that a leakage in both edges of the slot 3 is prevented and at the same time the falling of the boundary elements is prevented.

Furthermore, a lid is inserted from the side and adjusted by moving this cover the width of the outflow from the slot 3.

In Fig. 4 is one from the Japanese patent 6-198240 known device for regulating the Ausströmbreite shown. This device is shown in the oblique view and in a reversed position by 180 °.

With 1 is like at FIG. 3 the application head and with 2 is in the width direction of the applicator head extending application medium chamber, in which the application medium is filled, called.

Furthermore, a dispensing slot 3, which is connected to the application medium chamber 2 and opens downwards, is likewise present. A cap shaft a is inserted into the application medium chamber 2, and the front edge part b is made of a plastic material and has a liquid-tight structure. In addition, its inner part is hollow, so that application medium can flow into it. On the cap shaft a, a lid c is attached, the front edge portion d also consists of a plastic material and has a liquid-tight construction and is inserted into the interior of the discharge slot 3. With e the order medium is designated.

A disadvantage is that between the limiting element and the opening of the discharge slot 3, a gap remains, can run out of the application medium (leakage) or the limiting element falls out. Therefore, after the restriction member has been inserted, it is necessary to close the gap to rotate a plurality of profile regulating bolts and to move the nozzle lip 1d in the direction of the associated other nozzle lip 1c. This requires a lot of effort. Furthermore, when the nozzle lip 1d is moved, the profile regulation must be performed again from the beginning.

When using the in Fig. 4 In principle, the same disadvantage is described (cover d is moved, to close the gap, the plurality of profile regulating bolts must be actuated and the nozzle lip 1d is moved in the direction of the other nozzle lip 1c). Again, since the opening of the slot is narrow at 0.3 to 0.5 mm, the lid d is necessarily too thin and it will bend or drag as it moves.

The invention has for its object to provide an easier to operate device for regulating the coating width of a curtain coater.

The object of the invention is achieved in that the limiting element consists of a flexible plate which can be inserted from below into the discharge slot and zigzag-shaped bendable when inserted into the discharge slot, wherein the thickness of the flexible plate is less than the width of the opening of the Abgabeschlitzes and that a projecting from the discharge slot protruding part of the limiting element is held together with an existing flexible cover of the edge region of the discharge slot on the outer side surface of the applicator head.

It is useful if the flexible plate of the limiting element consists of a plastic material. This makes it very easy that the boundary element are kicked alternately several times can and can be inserted from the bottom of the dispensing slot.

It is also proposed that the cover is made of a thin, flexible plate made of a plastic material. An advantageous embodiment of the limiting element is that it preferably consists of vinyl chloride. The cover, however, preferably made of polypropylene.

It is advantageous if the edge part of the delimiting element and the edge part of the cover are first glued together (this can be done very easily with double-sided adhesive tape) and then fastened together to the outside surface of the application head.

For attachment, it is expedient if a holder is provided for it.

This holder can be suitably designed by having a pressure hose. This pressure hose is positioned in existing channels, wherein the grooves are present on both outer side surfaces and arranged horizontally there in the width direction of the applicator head.

In addition, the holder also has a pressure hose from the outside holding pressure plate. The pressure hose can be filled with air so that it expands and thereby holds the edge part of the limiting element and the edge part of the cover.

In this way, the edge part of the limiting element and the edge part of the cover are clamped very simply and securely between the channel and the pressure hose.

• Um in beide seitlichen Randteile des Abgabeschlitzes des Auftragskopfes je ein Begrenzungselement mit einer der Ausströmbreite entsprechenden Breite einführen zu können, wird eine flexible Platte aus Plastik, deren Dicke geringer ist als der Schlitz des Auftragskopfes, in erforderlicher Länge per Hand in das Innere des Schlitzes eingeführt. Der dann noch aus dem Schlitz herausstehende Teil wird geknickt, indem er an die scharfe Kante am unteren Rand der einen Düsenlippe der paarigen Lippen, die zwischen sich den Abgabeschlitz einschließen, gedrückt wird. Die geknickte Platte wird noch weiter in erforderlicher Länge in das Innere des Schlitzes eingeführt und der aus dem Schlitz herausstehende Teil wird erneut - nun in entgegengesetzte Richtung geknickt, indem er an die scharfe Kante am unteren Rand der anderen Lippe der paarigen Lippen, gedrückt wird. Dadurch, dass dieser Vorgang beliebig oft wiederholt wird, entsteht eine Zickzackform des Begrenzungselementes. Der nach dem Einführen verbleibende Rest wird umgebogen und an der Außenseitenfläche des Auftragskopfes gehalten. Die Anzahl der Knicke sollte im Übrigen nach der Durchflussmenge des aufzubringenden Auftragsmediums und des Flüssigkeitsdrucks entschieden werden.
• Das Begrenzungselement und die Abdeckung sind gemeinsam an der Außenseitenfläche des Auftragskopfes gehalten.
• Um die Ausströmbreite des Auftragsmediums bzw. die Vorhangsbreite und damit die Beschichtungsbreite zu verändern, ist das alte Begrenzungselement und die alte Abdeckung entfernbar und gegen Bauteile mit veränderten Abmaßen austauschbar.
• Das Begrenzungselement und die Abdeckung auf diese Art und Weise anzubringen und zu entfernen, ist äußerst einfach und beim Anbringen und Entfernen des Begrenzungselementes und der Abdeckung ist es nicht notwendig, wie herkömmlich, die Öffnung des Abgabeschlitzes zu manipulieren.
• Folglich hat die vorliegende Erfindung die folgenden Effekte:
  1. a) Es ist nicht notwendig, nach Einführung des Begrenzungselementes die Profilregulierung noch einmal durchzuführen, so dass sich der Aufwand in großem Maße verringert.
  2. b) Da die Platte für das Begrenzungselement dünner ist als die Öffnung des Schlitzes, ist die Einführung einfach.
  3. c) Da das Begrenzungselement flexibel ist und außerdem von oben her Flüssigkeitsdruck erhält, zieht sich die Zickzackform in Längsrichtung zusammen und durch den Keileffekt erhöht sich der Flächendruck der Lippen auf beiden Seiten, so dass die Flüssigkeitsdichtigkeit hervorragend ist.
  4. d) Da das Begrenzungselement und die Abdeckung einfach herstellbar sind, ist die Vorrichtung sehr kostengünstig.
• Im Folgenden wird eine Ausführungsform der vorliegenden Erfindung an Hand der Zeichnungen erklärt.

In the following, effect and effect of the present invention will be explained.

• In order to be able to introduce a respective boundary element with a width equal to the Ausströbreite in both lateral edge portions of the discharge slot of the applicator head, a flexible plate made of plastic, whose thickness is less than the slot of the applicator head, inserted in the required length by hand in the interior of the slot , The then still protruding from the slot part is kinked by being pressed against the sharp edge at the bottom of the one nozzle lip of the paired lips, which between them include the discharge slot. The kinked plate is further inserted in the required length in the interior of the slot and the part protruding from the slot is again - now kinked in the opposite direction by being pressed against the sharp edge at the bottom of the other lip of the paired lips. The fact that this process is repeated as often as desired, creates a zigzag shape of the limiting element. The remainder after insertion is bent over and held on the outside surface of the applicator head. Incidentally, the number of kinks should be decided according to the flow rate of the application medium to be applied and the fluid pressure.
• The restriction member and the cover are held together on the outer side surface of the applicator head.
• In order to change the Ausströmbreite the application medium or the curtain width and thus the coating width, the old limiting element and the old cover is removable and interchangeable with components with changed dimensions.
• Attaching and removing the restrictor and cover in this manner is extremely easy and easy to install and removal of the restriction member and the cover, it is not necessary, as is conventional, to manipulate the opening of the delivery slot.
• Consequently, the present invention has the following effects:
  1. a) It is not necessary to perform the profile adjustment again after the introduction of the limiting element, so that the effort is reduced to a great extent.
  2. b) Since the plate for the restriction member is thinner than the opening of the slot, the introduction is easy.
  3. c) Since the restriction member is flexible and also receives fluid pressure from above, the zigzag form contracts in the longitudinal direction and the wedge effect increases the surface pressure of the lips on both sides, so that the liquid-tightness is excellent.
  4. d) Since the limiting element and the cover are easy to produce, the device is very inexpensive.
• Hereinafter, an embodiment of the present invention will be explained with reference to the drawings.

Show it:

Fig.1 :

a sectional view of the device for regulating the coating width according to the present invention (view between the arrows A - A off Fig. 2 )

Fig. 2 :

a view between the arrows B - B off Fig. 1 ,

Figure 3

a sectional view of the applicator head used in a known curtain coater.

4 :

an oblique view of another device for regulating the Ausströmbreite according to the prior art.

In the FIGS. 1 and 2 are components that come with components from the FIGS. 3 and 4 are identical with the prior art, provided with the same reference numerals.

In the figures, 1 designates the curtain applicator head of the curtain coater. An application medium chamber 2 extending in the width direction of the application head 1 contains the application medium to be applied, for example coating color. With 3 of the associated with the application medium chamber 2, downwardly open discharge slot is designated. 4 is a limiting element.

This limiting element 4 consists of a flexible plate, made of a plastic material and has a smaller thickness than the opening of the discharge slot 3. If z. B. the opening of the discharge slot 3 is about 0.3 mm, the thickness of the plate or the limiting element 4 is about 0.2 mm. The limiting element 4 is inserted from the lower edge of the slot. In this case, a zigzag shape is formed. To form this zigzag shape, the plate 4 is inserted in the required length in the interior of the slot 3 and protruding from the slot 3 part is kinked by the sharp edge at the bottom of the one nozzle lip 1 d of the paired lips, the Form discharge slot 3, is pressed. The kinked plate or the limiting element is introduced further in the required length in the interior of the discharge slot and the projecting out of the slot part is again, now bent in the opposite direction. This is done by touching the sharp edge of the other lip 1 c the paired lips forming the slot 3 is pressed. Because this process can be done manually and as often as is repeatable, a sealing of the edge regions of the dispensing slot is very easy and inexpensive possible.
The remaining after the introduction of the limiting element 4 rest is guided upward and held on the outer side surface of the applicator head 1.

5 is a cover. The cover 5 consists of a thin, flexible plate made of a plastic material. The cover 5 has the same width as the restriction member 4. The cover 5 externally covers the lower edge of the discharge slot 3 at the part where the restriction member 4 has been inserted. The two ends of the cover are also raised as the spacer remainder or guided upwards and held on the outer side surface of the applicator head 1.

Hereinafter, the bracket that holds the edge part of the restriction member 4 and the edge part of the cover 5 on the outside surface of the application head 1 will be explained.

The holder 6 consists of a pressure hose 6b and a pressure tube holding the pressure plate 6c. The pressure hose 6b is positioned in a groove 6a. This groove runs horizontally along the outside surface of the application head 1 in the width direction, i. transverse to the direction of not marked with the fibrous web. The holder 6 also has a pressure plate 6c which holds the pressure tube 6b from the outside.

Between the groove 6a and the pressure hose 6b, the edge part of the limiting element 4 and the edge part of the cover 5 is clamped. This clamping is achieved by applying the Pressure hose 6b with air, so that this expands. The components 4 and 5 can thus be very easily fixed to the outer side surface of the applicator head 1. Further, 6d denotes a fixing bolt for fixing the pressure plate 6c to the outer side surface of the application head 1.
Before the one edge of the limiting element 4 and the one edge of the cover 5 are held together by means of the holder 6, they can be glued together for easier fixing with double-sided adhesive tape.

It should be mentioned that in FIG. 2 a final plate 10 is shown, which is present on the edge surface of the applicator head 1. In addition, located at the side surface of a feed 11 for filling the application medium chamber 2 with the application medium.

• Durchflussmenge: 10 Liter/m/min
• Druck: 1,5 kg/cm2
• Anzahl der Knicke: 2

Incidentally, the number of kinks of the restriction member 4 should be decided according to the flow rate of the paint and the liquid pressure. The following values were chosen for the example:

• Flow rate: 10 liters / m / min
• Pressure: 1.5 kg / cm2
• Number of kinks: 2

The present invention is not limited to the above-described embodiment, and unless otherwise departing from the gist of the invention, other embodiments are possible.

LIST OF REFERENCE NUMBERS

1

gun

1c

die lip

1d

die lip

2

Application medium chamber

3

dispensing slot

4

limiting element

5

cover

6

bracket

6a

gutter

6b

pressure hose

6c

printing plate

6d

mounting bolts

10

End plate

11

Feeder for the application medium

Claims (8)

Apparatus for regulating the coating width of a coating to be applied by a curtain coater, comprising an applicator head (1) with an application medium chamber (2), and a dispensing slot (3) emanating from the application medium chamber (2) for dispensing a liquid to pasty application medium to one running paper, cardboard or other fibrous web, wherein at both lateral ends of the discharge slot (3) in each case a limiting element (4) in the discharge slot (3) can be inserted,
characterized in that
the limiting element (4) consists of a flexible plate which can be pushed into the delivery slot (3) from below and which can be zigzag - shaped when inserted into the discharge slot (3), the thickness of the flexible plate being less than the width of the opening in the delivery slot Discharge slot (3) and that a projecting from the discharge slot (3) outstanding part of the spacer (4) is held together with an existing flexible cover (5) of the edge region of the discharge slot (3) on the outer side surface of the applicator head (1). Device according to claim 1,
characterized in that
the flexible plate of the limiting element (4) consists of a plastic material and is alternately kinkable and alternately inserted from the lower edge of the discharge slot (3). Apparatus according to claim 1 or 2,
characterized in that
the cover (5) is made of a flexible plate made of a plastic material Apparatus according to claim 1 to 3,
characterized in that
the edge part of the limiting element (4) and the edge part of the cover (5) are glued together and held on the outer side surface of the applicator head. Device according to claims 2 and 3,
characterized in that
the limiting element (4) is preferably made of vinyl chloride and the cover (5) is preferably made of polypropylene. Device according to one of claims 1 to 5,
characterized in that
a holder (6) is provided, which holds the edge part of the limiting element (4) and the edge part of the cover (5) on the outer side surface of the applicator head (1). Device according to claim 6,
characterized in that
the holder (6) has a pressure hose (6b) positioned inside the grooves (6a) horizontally provided on both sides in the width direction of the outside surface of the application head (1), and the holder (6) also has a pressure hose (6b ) holding from the outside pressure plate (6c), wherein between the groove (6a) and the pressure hose (6b) of the edge part of the limiting element (4) and the edge part of the cover (5) is enclosed. Device according to claim 7,
characterized in that
the pressure hose (6b) can be filled with air so that it expands and thereby holds the edge part of the limiting element (4) and the edge part of the cover (5).

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