EP3697543B1 - Curtain application unit and method for applying an application medium - Google Patents
Curtain application unit and method for applying an application medium Download PDFInfo
- Publication number
- EP3697543B1 EP3697543B1 EP18782395.0A EP18782395A EP3697543B1 EP 3697543 B1 EP3697543 B1 EP 3697543B1 EP 18782395 A EP18782395 A EP 18782395A EP 3697543 B1 EP3697543 B1 EP 3697543B1
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- EP
- European Patent Office
- Prior art keywords
- curtain
- air
- medium
- application
- applicator
- Prior art date
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Images
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H23/00—Processes or apparatus for adding material to the pulp or to the paper
- D21H23/02—Processes or apparatus for adding material to the pulp or to the paper characterised by the manner in which substances are added
- D21H23/22—Addition to the formed paper
- D21H23/46—Pouring or allowing the fluid to flow in a continuous stream on to the surface, the entire stream being carried away by the paper
- D21H23/48—Curtain coaters
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05C—APPARATUS FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05C5/00—Apparatus in which liquid or other fluent material is projected, poured or allowed to flow on to the surface of the work
- B05C5/005—Curtain coaters
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05C—APPARATUS FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05C5/00—Apparatus in which liquid or other fluent material is projected, poured or allowed to flow on to the surface of the work
- B05C5/007—Slide-hopper coaters, i.e. apparatus in which the liquid or other fluent material flows freely on an inclined surface before contacting the work
- B05C5/008—Slide-hopper curtain coaters
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H23/00—Processes or apparatus for adding material to the pulp or to the paper
- D21H23/02—Processes or apparatus for adding material to the pulp or to the paper characterised by the manner in which substances are added
- D21H23/22—Addition to the formed paper
- D21H23/30—Pretreatment of the paper
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05C—APPARATUS FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05C9/00—Apparatus or plant for applying liquid or other fluent material to surfaces by means not covered by any preceding group, or in which the means of applying the liquid or other fluent material is not important
- B05C9/06—Apparatus or plant for applying liquid or other fluent material to surfaces by means not covered by any preceding group, or in which the means of applying the liquid or other fluent material is not important for applying two different liquids or other fluent materials, or the same liquid or other fluent material twice, to the same side of the work
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D1/00—Processes for applying liquids or other fluent materials
- B05D1/30—Processes for applying liquids or other fluent materials performed by gravity only, i.e. flow coating
- B05D1/305—Curtain coating
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D2252/00—Sheets
- B05D2252/02—Sheets of indefinite length
Definitions
- the invention relates to a curtain application unit according to the preamble of claim 1 and a method for coating a moving web of material, in particular a fibrous web according to the preamble of claim 9.
- a coating In the production of fibrous webs such as paper or cardboard webs, a coating, a so-called coat, is often applied to one or both sides of the material web to improve the surface properties.
- coating using a curtain applicator has become established in recent years.
- curtain applicators are often used in paper or B&P production to achieve a particularly high coating quality with little use of expensive coating color. Curtain applicators are therefore often used to produce the top layer, the so-called top layer. Since the top layer of the paper or B&P web is the layer that determines the outer appearance of the paper or board, particularly high quality requirements are placed on the top layer.
- a high quality of the coating is also an important quality criterion when using such coating units for layers below the top layer.
- Curtain applicator units for coating a moving web of material with at least one liquid and/or pasty application medium generally have an application head which comprises at least one tear-off edge which essentially extends over the width of the application head and at which the application medium leaves the application head in the form of a freely falling curtain .
- Such a curtain is particularly susceptible to air currents.
- the curtain is particularly sensitive in applications where a large curtain height is required or desired, or with low flow rates of coating color.
- curtain application units are generally operated in a housing or encapsulation which surrounds them and is air-conditioned.
- a further object of the invention is to propose a curtain application unit in which the curtain remains largely unaffected by air currents, even with a greater curtain height or a smaller application quantity of application medium.
- a further object of the invention is to enable simple maintenance and control of the curtain applicator unit, so that the curtain is not affected at all or only to a very small extent by the movements of the operating personnel.
- a further object of the invention is to propose a compact and flexible design for a curtain applicator unit, in order to also enable subsequent installation even in the case of cramped space conditions and given web routing.
- a curtain applicator for applying a liquid or pasty application medium to at least one surface of a running material web, in particular a fibrous web.
- the curtain applicator includes an applicator head with at least one tear-off edge that extends essentially across the width of the applicator head and at which the application medium leaves the applicator head in the form of a freely falling curtain.
- at least one flushing device is provided, by means of which at least one of the at least one tear-off edge can be subjected to a flowing gaseous flushing medium.
- At least one blocking device is provided, which is suitable for keeping air movements in the ambient air away from the curtain.
- the blocking device according to the invention ensures that the curtain remains largely unaffected by air currents, even with a greater curtain height.
- the curtain applicator can be adapted to the conditions of the installation situation, the run of the material web, etc., so that maintenance and inspection of the curtain applicator can be carried out easily possible without the curtain being significantly affected by operator movements.
- At least one flushing device by means of which at least one of the at least one tear-off edge can be or is acted upon by a flowing gaseous flushing medium, means that little or no ambient air can collect in the area of the tear-off edge, which is at the tear-off edge can condense.
- the combination of flushed tear-off edge and locking device means that air conditioning can be completely dispensed with or only very simple air conditioning can be used.
- the invention can make it possible to dispense with the otherwise customary complete housing of the curtain applicator together with part of the running web of material. This significantly simplifies the design and installation of the curtain applicator unit in a coating system, even when space is limited, and also significantly reduces the costs incurred.
- the invention also has a high degree of flexibility with regard to the options for web routing, since many of the restrictions on web routing that result from a fixed housing are now eliminated.
- the application head preferably comprises at least one transverse distribution chamber and a nozzle gap connected thereto with an outlet opening in such a way that the application medium coming from the transverse distribution chamber via the nozzle gap to the outlet opening leaves the application head at the outlet opening, with the at least one tear-off edge being formed by at least part of the outlet opening is.
- the outlet opening can provide a first and a second tear-off edge, with the first tear-off edge being arranged at the front and the second tear-off edge at the rear when the application head is used as intended, viewed in the running direction of the material web.
- a preferred development of the invention provides a first and/or a second flushing device which is or are arranged in such a way that when the application head is used as intended in the direction of travel of the material web considered, the first flushing device applies the flushing medium to the first tear-off edge from the front and the second flushing device applies the flushing medium to the second tear-off edge from the rear.
- the application head comprises at least one transverse distribution chamber and a nozzle gap connected to it with an outlet opening as well as an adjoining sliding surface, which in turn is adjoined by the tear-off edge in such a way that, viewed in the flow direction of the application medium, the The application medium coming from the transverse distribution chamber via the nozzle gap and the outlet opening flows after the outlet opening over the sliding surface to the tear-off edge and leaves the application head at the tear-off edge.
- the at least one flushing device can be arranged outside of the nozzle gap.
- the at least one flushing device is preferably designed and arranged in such a way that the flow of the gaseous flushing medium is directed in the direction of the freely falling curtain.
- the application head can comprise a housing block, in particular made of a metallic material, in which the transverse distribution chamber and the nozzle gap are arranged, with the housing block being surrounded at least in sections by an outer covering and/or a thermally insulating layer which comes into contact with the environment .
- the metallic material can in particular be steel, in particular alloyed or unalloyed stainless steel.
- the classification of steels and stainless steels can be found in DIN EN 10020.
- the outer cladding can be provided, for example, at least in sections, by at least one flat and/or curved metal sheet or by at least one flat and/or curved plastic plate such as a plexiglass plate.
- the outer lining can be thermally decoupled from the housing block at least in sections by the thermally insulating layer.
- the thermally insulating layer is arranged at least in sections between the outer cladding and the housing block.
- the external cladding which is thermally decoupled from the housing block, ensures that the ambient air does not come into direct contact with the "cool" housing block through which the application medium is guided.
- this has the advantage that the risk of condensation on the housing block is reduced.
- the housing block is also prevented from being heated by warmer ambient air, which can result in deformation of the housing block. Due to the high demands on the accuracy, e.g. of the die gap, even small deformations can have a major impact on the quality of the coating.
- Such nozzle isolation allows the CD profile quality of the coating to be maintained constant.
- the outer lining can also be formed at least in sections by a thermally insulating layer.
- thermally insulating layer can be constructed.
- the thermally insulating layer comprises a foam material and/or a honeycomb structure and/or glass wool and/or mineral wool or is constituted by one or more of the foregoing.
- the thermally insulating layer is formed by a gaseous insulating medium which is arranged or guided in a gap between the housing block and the outer paneling, with the gap in the area of the tear-off edge in particular being in the range of 0.5mm - 50mm, preferably 2- 10mm.
- the gaseous insulation medium is provided at least partially, preferably completely, by the flowing gaseous flushing medium. In this case, insulation of the housing block and flushing of the at least one tear-off edge can be provided in a particularly simple manner.
- the gaseous insulation medium and/or the gaseous flushing medium is, in particular, air, it being possible for the air to be conditioned in terms of its temperature and/or its moisture content before it is used as flushing medium and/or insulation medium.
- At least one blocking device is arranged before or after the application head in the running direction of the material web.
- two or more locking devices can also be provided, with at least one locking device being arranged in front of the application head and at least one locking device being arranged after the application head.
- the at least one blocking device in particular all blocking devices, comprise means for generating an air shield, in particular comprising one or more air nozzles.
- the flow direction of the air of the air shield has a component that points away from the applicator head and/or has a component that points away from the material web.
- the blocking effect of the blocking device is realized in that an air flow is generated in a targeted manner, but this is directed in such a way that it does not disturb the curtain.
- the air flow of the air shield should be dimensioned so strongly that the air movements of the ambient air, which are generated, for example, by the movement of the operating personnel, do not penetrate through the air shield or only penetrate to a very limited extent.
- the air shield will often extend at least over the width of the web of material or the width of the curtain, or even go a little beyond that.
- the amounts of air can advantageously be in the range between 0.2 m 3 /min/m and 12 m 3 /min/m.
- the amounts of air can particularly preferably be between 0.5 m 3 /min/m and 0.9 m 3 /min/m.
- the amounts of air can also be more than 1.2 m 3 /min/m, in particular between 2.4 and 9 m 3 /min/m.
- the information on the air volume is measured at 20°C and 1 bar pressure.
- Another major advantage of this air shield is that the operating personnel can simply switch off the air shield for repair or maintenance work, or can simply reach through the air shield. A possibly complex dismantling of a permanently installed rigid device can thus be omitted.
- a suitable collecting vessel or sample carrier can be guided through the air shield to the curtain. To do this, neither the application process has to be interrupted nor the air shield switched off.
- the distance between the blocking device and the application head is less than 150 cm, in particular less than 100 cm, particularly preferably less than 50 cm.
- the risk can be reduced that air movements are generated in the space between the barrage and the curtain applicator, which can have a disruptive effect on the curtain.
- such a close arrangement can prevent operating personnel from being between the blocking device and the curtain applicator unit during operation.
- the operating personnel of the machine can reach through the air shield and work on the nozzle or the curtain, such as taking samples. This enables the operating personnel to work easily, without the operation being disrupted by the movement of the operating personnel or the air currents generated thereby.
- a distance of 20 cm or more, in particular 25 cm or 30 cm and more, can preferably be selected. Such a On the one hand, positioning makes it easier to attach the air nozzles. On the other hand, it can also be avoided that a suction is generated by the rising air of the air shield, which can then disturb the curtain.
- the flushing device and the at least one blocking device are connected to a common air supply.
- the common air supply can be a central compressed air supply, which is usually present in the production hall anyway.
- fans or compressors can also be used as air pressure generators for the air shield and/or the flushing devices.
- Unconditioned air can be used, which is taken directly from the vicinity of the curtain applicator, for example.
- devices for conditioning the air specifically for adjusting the temperature and humidity, can also be provided.
- flushing device or flushing devices are operated with air at a higher air pressure than the air shield or shields.
- flushing devices can be operated using the central compressed air supply, while the air shield is generated by a fan or compressor
- the nozzles that are used with compressors usually have slot widths of less than 0.8 mm.
- the air nozzles, which are operated with fans to generate air shields, usually have slot widths of less than 3 mm.
- air jets with Compressors work with high static pressures ( ⁇ 10 bar).
- Air nozzles with fans usually work with low static pressures ( ⁇ 1 bar).
- the flushing devices and the air shields are operated with different compressed air generators, it can be advantageous that they can be connected to the same compressed air generator.
- the air shield can also be connected to the central compressed air supply, which also supplies the flushing devices, and can therefore continue to be operated in an uncomplicated manner.
- the connectivity can be implemented, for example, via a shut-off valve or the like.
- a hose connection for example, has to be repositioned. It is essential that the connection can be made quickly without major structural measures.
- the curtain applicator preferably has means for adjusting the temperature of the flushing medium and/or the application medium. It is advantageous that the temperature of the flushing medium is between the temperature of the environment and the temperature of the application medium or below the temperature of the application medium or below the temperature of the ambient air.
- the means are designed in particular to set the temperature of the flushing medium in the range from 0.4 to 1.5 times, preferably from 0.6 to 1.5 times, the temperature of the environment and/or the application medium .
- the information on multiples should refer to the temperature value in °C.
- the means for adjusting or coordinating the temperature of the flushing medium and/or the temperature of the application medium can in particular Include heating and / or cooling devices and temperature measuring devices, by means of which the temperature of the rinsing medium and the application medium can be measured and each set to a desired value.
- the means preferably also include a control and/or regulation device with which the heating and/or cooling devices are automatically regulated and/or controlled on the basis of the measured temperatures of the rinsing medium and the application medium and the target temperatures for the rinsing medium and the application medium.
- the curtain applicator preferably includes means for dehumidifying the flushing medium or for reducing the moisture content of the flushing medium.
- means for dehumidifying the flushing medium or for reducing the moisture content of the flushing medium can be provided for this.
- a dehumidifying device can be provided which is assigned directly to the curtain applicator, in particular to the rinsing device.
- the flushing medium is air which is taken from the compressed air system of the factory or workshop. This air is usually already conditioned to a certain humidity and temperature. Depending on the application, this dehumidification of the air, which has already been carried out for the compressed air system of the factory, can already be sufficient.
- the means for dehumidifying the compressed air can be attributed to the curtain applicator as indirect means for dehumidifying.
- the curtain applicator includes means, in particular sensors, for determining the temperature of the application medium and/or the temperature of the rinsing medium and/or the relative humidity of the rinsing medium.
- the invention makes it possible in particular for the curtain applicator to have no housing. In this case, a particularly compact design and a very high level of flexibility in guiding the material web are possible.
- the curtain applicator has a housing, with the housing not being air-conditioned.
- the housing is designed in such a way that it surrounds at least the application head and the area where the curtain of application medium meets the fibrous web.
- such a housing is not completely closed and, for example, is only open at the top or on one side. Since the enclosure is not air-conditioned, this is easily possible.
- the distance between the opening and the material web is at least 100 mm. In many preferred applications the distance may be between 120mm and 180mm. However, distances of more than 200 mm or more than 300 mm can also occur. With such an embodiment, the drop height of the curtain when the curtain is applied is comparatively very large.
- the curtain here is also very susceptible to disturbances, especially air movements of the surrounding air. The invention can be used to advantage in such an embodiment.
- the at least one blocking device comprises a plate which is attached to or in the immediate vicinity of the application head and extends essentially parallel to the curtain.
- a plate can be installed before or after the curtain, viewed in the running direction of the material web.
- a further plate can also be provided, which is attached to or in the immediate vicinity of the application head. In this case, one plate is often provided in front of the curtain and the other plate is provided after it.
- one or both of these plates are provided at a distance from the curtain of less than 100 mm, preferably less than 50 mm.
- the curtain applicator unit can also include a scraper device which is suitable for keeping air entrained with the web of material away from the curtain.
- a stripping device can usually be arranged in front of the applicator head, viewed in the running direction of the material web. So-called air knives (air-cut), for example, are known in the industry as suitable stripping devices.
- the scraping device often extends to just before the point of impact of the curtain. In contrast to the locking device, this wiping device only acts against the air boundary layer in the immediate vicinity of the moving material web and is not suitable for keeping air movements in the ambient air, which are caused, for example, by the movement of operating personnel or rotating machine parts, away from the curtain.
- the outer lining is preferably arranged and designed in such a way, at least in the area of the tear-off edge, that it does not impair the free fall of the curtain.
- the housing block comprises a first and a second housing block part and the transverse distribution chamber and the nozzle gap are formed by a cavity formed between the two housing block parts.
- the two housing block parts are connected to one another by connecting means, in particular screws.
- first housing block part comprises a first nozzle lip providing the first tear-off edge and the second housing block part comprises a second nozzle lip providing the second tear-off edge, which can be adjusted relative to one another in such a way that the width of the die gap in the region of the outlet opening is in the transverse direction of the application head, and thus in the transverse direction of the fibrous web, is individually adjustable.
- This configuration allows the application head according to the invention structurally particularly simple to build with an adjustable nozzle gap.
- the applicator head has an upper side and an underside and the outlet opening is arranged on the underside.
- the flushing medium that at least partially provides the insulating medium flows in a flow direction directed from the top to the bottom, in particular from the top to the bottom, to the area of the tear-off edge.
- the conditioned rinsing medium e.g. air
- the conditioned rinsing medium should have a suitable humidity and a suitable temperature so that the formation of condensation, e.g. on the lips of the application head or its tear-off edge, can be reliably avoided or eliminated.
- the object is achieved by a method according to claim 9.
- the curtain applicator includes a blocking device, which in turn includes means for generating an air shield.
- a blocking device which in turn includes means for generating an air shield.
- they can be one or more air nozzles.
- the speed of the air of the air shield can be between 10 m/s and 60 m/s, in particular between 20 m/s and 50 m/s.
- Advantageous amounts of air can be in the range between 0.2 m 3 /min/m and 1.2 m 3 /min/m. In particular, the amounts of air can be between 0.5 m 3 /min/m and 0.9 m 3 /min/m.
- air quantities of more than 1.2 m 3 /min/m, in particular between 2.4 and 12 m 3 /min/m provide very advantageous results and stable air shields.
- the air shield can advantageously be produced by means of a slit nozzle which has a slit width of between 1 mm and 5 mm, in particular between 2 mm and 4 mm.
- the air used for the air shield is processed.
- the processing can include, for example, filtering and/or dehumidifying and/or heating or cooling.
- An advantageous embodiment of the method is characterized in that the application medium is fed through the application head at a flow rate of less than 10 l/min*m, in particular less than 6 l/min*m, particularly preferably between 2 l/min*m and 5 l/min*m is applied.
- the use of a curtain application device according to the invention with a blocking device is particularly advantageous here. Especially when the drop height of the curtain is more than 100mm, more than 200mm, or 300mm and more.
- the application medium can also be advantageous to apply the application medium at a higher flow rate, for example 20 l/min*m, 25 l/min*m or more. In this way it is also possible to apply quantities of 20 g/m 2 or even 30 g/m 2
- the material web is moved at a speed of between 100 m/min and 1200 m/min, in particular between 200 m/min and 800 m/min.
- the composition and/or the thickness of the curtain must be adjusted accordingly, which in turn also makes the curtain more susceptible to ambient air.
- the use of a curtain application device according to the invention with a blocking device is again particularly advantageous.
- the method can also be used advantageously at speeds above 800 m/min, for example at 1000 m/min, 1200 m/min, 1500 m/min or more
- Table 1 clearly shows that it is very important for a wide range of applications to be able to stably implement application of low flow rates.
- the invention is very advantageous for the embodiments shown in Table 1, particularly but not exclusively in combination with a curtain height of 100mm or more.
- coat weights shown here between 8 g/m 2 and 14 g/m 2 are quite common. However, coat weights of up to 20 g/m 2 or more can also be realized with the method according to the invention and the device according to the invention.
- the gaseous flushing medium can in particular be air. If a flushing medium is mentioned in the further description of this method, this always means the gaseous flushing medium, unless something else is explicitly mentioned.
- the rinsing medium e.g. air
- the rinsing medium should have a suitable humidity and a suitable temperature so that the formation of condensation, e.g. on the lips of the application head or its tear-off edge, can be reliably avoided or eliminated.
- the temperature of the flushing medium can be lower, higher or equal to the temperature of the application medium.
- a preferred embodiment of the method provides that the temperature of the flushing medium is kept between the temperature of the environment and the temperature of the application medium.
- An alternative advantageous embodiment of the method provides that the temperature of the flushing medium is slightly, for example less than 10°K, specifically 7°K or 5°K, below the temperature of the application medium and/or below the temperature of the ambient air.
- the temperature of the rinsing medium is in the range from 8°C to 55°C, preferably from 18°C to 40°C, and that of the application medium in the range from 18°C to 40°C, preferably 25° C to 35°C and the ambient temperature is less than 65°C.
- the temperature of the flushing medium preferably deviates by up to 7°K, particularly preferably by a maximum of 5°K, down or up from the temperature of the application medium.
- the temperature of the flushing medium is greater than the temperature of the application medium.
- the temperature of the flushing medium can be between 4°K and 25°K, specifically between 7°K and 15°K higher than the temperature of the application medium.
- the relative humidity of the flushing medium is less than 100 RH%. Particularly advantageously, it can be provided that the relative humidity of the flushing medium is less than 80% RH or less than 70% RH.
- the temperature of the housing block will essentially correspond to the temperature of the application medium. (Possibly with a difference of 1°K, 2°K or a maximum of 5°K). The tear-off edge will then assume the same temperature.
- the rinsing medium for example the rinsing air
- the rinsing medium is inflowing with the Tear-off edge or the other parts of the housing block cooled down in the direction of the temperature of the application medium. This increases the relative humidity of the flushing medium. If the temperature of the flushing medium falls below the dew point, unwanted condensation can occur.
- the temperature of the rinsing medium is greater than the temperature of the application medium, and the moisture content of the rinsing medium is adjusted in such a way that the dew point of the rinsing medium is above the temperature of the application medium, in particular more than 2° K above the temperature of the application medium lies.
- the relative humidity of the flushing medium then remains well below 100% RH, for example at 80% RH, 70% RH or less, even after cooling at the tear-off edge, so that no condensation occurs on the nozzle lips or on the tear-off edge.
- the outflow speed of the flushing medium is between 6 m/min and 40 m/min, in particular between 12 m/min and 20 m/min
- the exit speed of the application medium from the application head is between 10 m/min and 200 m/min, in particular between 16 m/min and 66 m/min. Similar to temperature and humidity, there are great advantages when the outflow speed of the flushing medium and the exit speed of the application medium are coordinated.
- the outflow speed of the flushing medium is between 40% and 140%, in particular between 50% and 100% of the exit speed of the application medium.
- figure 1 shows schematically a curtain coater according to the prior art.
- FIG. 2 shows a curtain coater according to an aspect of the invention
- Figure 3 and 4 each show schematically a part of a curtain coater according to further aspects of the invention.
- FIGS. 5 to 11 show possible implementations of a gun according to various aspects of the invention.
- FIG. 1 shows a curtain coater as is known from the prior art.
- the web of material 4 is guided through a slit into a housing 30 . Supported by two rollers 3, it is passed under an application head 1, with a curtain 2 of application medium being deposited on the material web 4.
- the material web 4 is guided out of the housing again through a further slot.
- An air stripper 5, in particular an air cut, is provided to remove the entrained air.
- the housing 30 is air-conditioned by means of an air-conditioning system 31 .
- Such an enclosed curtain application unit cannot be operated stably without suitable air conditioning.
- the material web 4 is usually deflected by a non-contact deflection element 32, which is also known as an air turn 32, and, if necessary, passed on to drying.
- the housing 30 requires a relatively large amount of space.
- the necessary air conditioning is associated with considerable costs in terms of acquisition and operation.
- FIG 2 shows, in contrast, a curtain coater according to one aspect of the invention.
- an applicator head 1 is provided, from which the curtain 2 is applied to the running material web 4 .
- the application head 1 comprises at least one flushing device, by means of which at least one tear-off edge can be subjected to a flowing gaseous flushing medium such as air.
- the outer covering is thermally decoupled from the housing block, at least in sections, by a thermally insulating layer. This is very advantageous, but such insulation can optionally also be dispensed with.
- the material web 4 moves in the machine direction MD from left to right.
- the order takes place here between two deflection rollers 3, over which the material web is guided.
- the job can also be done on a roller, for example.
- a stripping device 5 is provided in front of the curtain 2 as seen in the running direction of the material web 4 .
- the stripping device 5 comprises or consists of a brush, foil or lip, which can be applied to the material web 4 . Both versions can fulfill the important function of the stripping device 5, namely to reduce or remove the air boundary layer carried along by the material web 4.
- the curtain commissioned work in figure 2 also shows two locking devices 9, one locking device 9 being arranged in front of the application head 1 and another locking device 9 being arranged after the application head 1.
- a nozzle arrangement 6 is provided in each case. These air nozzles 6 each produce an air shield 9, which achieves the desired blocking effect, namely to keep air movements in the ambient air away from the curtain 2.
- the air shield is directed here in both blocking devices 9 in such a way that the flow velocity of the air has a component that points away from the applicator head 1 and also has a component that points away from the material web 4 . In this way, a disruptive influence of the air shield on the web run or the curtain stability can be avoided most effectively.
- the curtain applicator is very flexible and can also be easily integrated into existing systems. On the one hand, it can be built very compactly, especially if there is no housing.
- the curtain coater requires only a relatively small amount of space in the cross-machine direction.
- the path of the material web 4 can also be adjusted.
- the web is fed in and out of the enclosure through a gap. This gap is fixed. In addition, it is usually also very narrow in order to ensure adequate air conditioning of the housing. This results in relatively strong restrictions for web guidance.
- FIG 2 shows by way of example that such restrictions are largely eliminated in the case of curtain coaters according to the invention.
- the courses 4a and 4b drawn in dashed lines show two possible courses of the material web 4, 4a, 4b before application.
- the deflection rollers 3a and 3b can be positioned comparatively close to the application unit.
- curtain applicator shown includes an applicator head 1, from which a curtain 2 is applied under the influence of gravity on a material web 4, such as a paper or cardboard web.
- a material web 4 such as a paper or cardboard web.
- the web of material 4 is thereby diverted by means of a deflection roller 3 so that it runs largely horizontally below the curtain 2 .
- the point of impact of the curtain is viewed in the running direction of the material web 4 somewhat behind the deflection roller 3 .
- So-called air knives (air-cut), for example, are known in the industry as suitable stripping devices 5 .
- the stripping device 5 often extends to just before the impact point of the curtain.
- a curtain coater is shown according to a preferred aspect of the invention.
- the at least one blocking device 9, 9a, 9b is implemented by an air shield 9.
- the air for generating the air shield 9 emerges from an air nozzle 6 or a row of nozzles 6 .
- the direction of flow of the air, and thus the alignment of the air shield 9, can go vertically upwards, or also be inclined slightly against this direction.
- this inclination is aligned away from the applicator head 1, and thus also away from the curtain 2, in order to avoid the curtain 2 being influenced by the air shield 9.
- the air shield 9 can extend at least over the entire width of the curtain 2 in the cross-machine direction.
- the air nozzle 6, or nozzle row 6 is attached directly to a stripping device 5.
- the distance between the air shield and the application head can advantageously be less than 150 cm, in particular less than 100 cm, particularly preferably less than 50 cm.
- a further deflection device such as a deflection roller 3a, is usually also provided after the curtain 2. The distance between this deflection device 3a and the curtain 3 can vary in different installations.
- the figure 5 shows - in a cross-sectional representation in a plane parallel to the web running direction MD and perpendicular to the web transverse direction CD (CD extends perpendicularly to the plane of the Figures 5-11 ) -
- the application head 1 has a transverse distribution chamber 23 and a nozzle gap 24 connected to it with an outlet opening 25 in such a way that the application medium coming from the transverse distribution chamber 23 via the nozzle gap 24 to the outlet opening 25 leaves the application head 1 at the outlet opening 25.
- the outlet opening 25 provides a front tear-off edge 26, viewed in the direction of web travel MD, and a rear tear-off edge 27, viewed in the direction of web travel MD.
- the application head 1 comprises a first flushing device 28 and a second flushing device 29 which are designed and arranged such that when the application head 1 is used as intended in the direction of web travel of the material web 4, the first flushing device 28 the first tear-off edge 26 from the front with a by a flowing scavenging medium 13 (dash-dotted line with arrow) and the second flushing device 29 acts on the second tear-off edge 27 from behind with a flowing scavenging medium 14 (dash-dotted line with arrow).
- the two flushing devices 28 , 29 are arranged outside of the nozzle gap 24 . In the present case, each of the two flushing devices provides a flushing medium in the form of air.
- the application head 1 comprises a housing block made of a metallic material, advantageously steel, in which the transverse distribution chamber 23 and the nozzle gap 24 are arranged.
- the housing block comprises a first housing block part 10 (front housing block part 10 in the present embodiment) and a second housing block part 11 (rear housing block part 11 in the present embodiment), with the transverse distribution chamber 23 and the nozzle gap 24 being formed by a cavity formed between the two housing block parts 10, 11 are formed.
- the first housing block part 10 a first nozzle lip 10.1, which provides the first tear-off edge 26 in the area of the outlet opening 25 of the nozzle gap 24.
- the second housing block part 11 includes a second nozzle lip 11.1, which provides the second tear-off edge 27 in the area of the outlet opening 25 of the nozzle gap 24.
- the two nozzle lips 10.1 and 11.1 can be adjusted relative to one another in such a way that the width of the nozzle gap 24 in the area of the outlet opening 25 can be individually adjusted in the transverse direction of the applicator head 1.
- the housing block is partially surrounded by an outer covering 12.1, 12.2, which comes into contact with the environment.
- the outer cladding 12.1, 12.2 has a part of the outer cladding 12.1 in the form of a bent sheet metal at the front in the web running direction MD and a part of the outer cladding 12.2 in the form of a bent sheet metal at the rear in the web running direction MD.
- the outer covering 12.1, 12.2 is arranged and designed in the area of the tear-off edges 26, 27 in such a way that the free fall of the curtain 2 is not impaired by this.
- the outer covering 12 is thermally decoupled from the housing block 10, 11 at least in sections by a thermally insulating layer.
- the thermally insulating layer between the front part of the outer cladding 12.1 and the front housing block part 10 is formed by a gaseous insulating medium, which is guided in a gap between the front housing block part 10 and the front part of the outer cladding 12.1 and flows out through the flowing gaseous flushing medium 13 the first flushing device 28 is provided.
- figure 5 upper part of the gap between the rear housing block part 11 and the rear part of the outer panel 12.2 formed by a foam material.
- the flushing medium flows in a flow direction directed from the top to the bottom to the two tear-off edges 26, 27.
- the figure 6 shows a variant of the in figure 5 gun 1 shown.
- the two flushing devices 28, 29 are attached in the lower area of the gun 1.
- Both the upper part of the gap between the rear housing block part 11 and the rear part of the outer paneling, 12.2, and the upper part of the gap between the front housing block part 10 and the front part of the outer paneling, 12.1 is completely or at least partially filled with a foam material .
- the figure 7 shows a second embodiment of an application head 1 according to the invention for producing a single-layer freely falling curtain 2.
- the order header figure 7 differs from that in the figure 5 Application head shown essentially in that the application head of figure 7 both rinsing devices 28, 29 are arranged in the lower area of the application head 1, i.e. at the height of the nozzle lips 10.1 and 11.1 and the outer lining 12.1 and 12.2 in front of and behind the curtain in the direction of the freely falling curtain 2 for up to 100 millimeters over the two tear-off edges 26 , 27 protrude at the outlet opening 25, whereby the freely falling curtain 2 is shielded from disruptive environmental influences such as air currents.
- the front part of the outer paneling 12.1 comprises a deflection plate 12.1.1.
- the rear part of the outer paneling 12.2 comprises a deflection plate 12.2.2, whereby the flowing flushing medium 14 provided by the second flushing device 29 is deflected onto the second tear-off edge 2.
- thermally insulating layer between the front part of the outer panel 12.1 and the housing block 10, 11 and the rear part of the outer panel 12.2 and the housing block 10, 11, respectively provided by air that is not provided by the flushing medium 13,14.
- another thermally insulating layer such as foam, mineral wool, etc., is used instead of the air.
- the figure 8 shows a third embodiment of an application head 1 according to the invention for producing a single-layer freely falling curtain 2.
- the application head 1 of figure 8 differs from that in the figure 5 application head shown essentially in that the thermally insulating layer between the rear part of the outer paneling 12.2 and the rear part of the housing block 11 is formed by the gaseous insulating medium, which is guided in the gap between the rear part of the housing block 11 and the rear part of the outer paneling 12.2 and through the flowing gaseous flushing medium 14 is provided from the second flushing device 29 .
- the figure 9 shows a further embodiment of an application head 1 according to the invention for producing a single-layer freely falling curtain 2.
- the application head 1 of figure 9 differs from that in the figure 8 Application head shown essentially in that no outer paneling 12.1 and 12.2 is provided.
- the housing block 10, 11 is only surrounded by the thermally insulating layer, which comes into contact with the environment, with the thermally insulating layer surrounding the front housing block part 10 being protected by the flowing gaseous flushing medium 13 from the first flushing device 28 and the rear
- the thermally insulating layer surrounding the housing block part 11 is provided by the flowing gaseous flushing medium 14 from the second flushing device 29 .
- the figure 10 shows another embodiment of an application head 1 according to the invention for producing a single-layer freely falling curtain 2.
- the application head 1 of figure 10 has a transverse distribution chamber 23 and a nozzle gap 24 connected to it with an outlet opening 25 as well as an adjoining sliding surface 17, which in turn is adjoined by a tear-off edge 16 such that viewed in the direction of flow of the application medium, it flows from the transverse distribution chamber 23 via the nozzle gap 24 and the outlet opening 25 coming application medium flows after the outlet opening 5 over the sliding surface 17 to the tear-off edge 16 and leaves the applicator head 1 at the tear-off edge 16.
- the sliding surface 17 is provided by a sliding surface block 15 arranged on the front housing block part 10 .
- Two flushing devices 28, 29 are provided on the tear-off edge 16, by means of which the flow-off gaseous flushing medium 13, 14 can be applied to the tear-off edge 16.
- the figure 11 shows an embodiment of an application head 1 according to the invention for producing a multi-layer freely falling curtain 2'.
- the application head 1 of figure 11 differs from that in the figure 8 Application head shown essentially in that the housing block has a housing block middle part 18 in addition to a front and rear housing block part 10', 11', and two transverse distribution chambers 23.1 and 23.2, each with an associated nozzle gap 24.1, 24.2, which meet at the outlet opening 25 by one to produce two-layer free-falling curtain 2'.
- the loading of the two tear-off edges 26, 27 and the thermal insulation of the housing block 10', 11', 18 is analogous to the embodiment of FIG figure 8 solved, namely the action of the first tear-off edge 26 with the flushing medium 13 provided by the first flushing device 28 and the action of the second tear-off edge 27 with the flushing medium 14 provided by the second flushing device 29, the two flushing media 13, 14 each coming from the upper part of the housing block 10' , 11', 18 are guided in the gap between the outer lining 12.1 or 12.2 in a direction of flow directed from the top to the bottom.
Landscapes
- Coating Apparatus (AREA)
- Application Of Or Painting With Fluid Materials (AREA)
Description
Die Erfindung betrifft ein Vorhang Auftragswerk gemäß dem Oberbegriff des Anspruchs 1 sowie ein Verfahren zur Beschichtung einer laufenden Materialbahn, insbesondere einer Faserstoffbahn gemäß dem Oberbegriff des Anspruchs 9.The invention relates to a curtain application unit according to the preamble of claim 1 and a method for coating a moving web of material, in particular a fibrous web according to the preamble of claim 9.
Bei der Herstellung von Faserstoffbahnen wie Papier- oder Kartonbahnen wird zur Verbesserung der Oberflächeneigenschaften häufig eine Beschichtung, ein sogenannter Strich auf eine oder beide Seiten der Materialbahn aufgetragen. Hierfür hat sich in den letzten Jahren das Beschichten mittels eines Vorhangauftragswerks etabliert.In the production of fibrous webs such as paper or cardboard webs, a coating, a so-called coat, is often applied to one or both sides of the material web to improve the surface properties. For this purpose, coating using a curtain applicator has become established in recent years.
Vorhangauftragswerke werden in der Papier- oder B&P Herstellung oftmals eingesetzt um eine besonders hohe Strichqualität bei geringem Einsatz der teuren Streichfarbe zu erreichen. Vorhangauftragswerke werden daher oftmals zur Erzeugung der obersten, der sog. Deckschicht, eingesetzt. Da die Deckschicht der Papier- oder B&P-Bahn die Schicht ist, welche die äußere Erscheinung des Papiers oder Kartons festlegt, werden an die Deckschicht besonders hohe Qualitätsanforderungen gestellt.Curtain applicators are often used in paper or B&P production to achieve a particularly high coating quality with little use of expensive coating color. Curtain applicators are therefore often used to produce the top layer, the so-called top layer. Since the top layer of the paper or B&P web is the layer that determines the outer appearance of the paper or board, particularly high quality requirements are placed on the top layer.
Jedoch ist auch beim Einsatz solche Auftragswerke in für Schichten unterhalb der Deckschicht eine hohe Qualität der Beschichtung ein wichtiges Qualtitätskriterium.However, a high quality of the coating is also an important quality criterion when using such coating units for layers below the top layer.
Vorhangauftragswerke zur Beschichtung einer laufenden Materialbahn mit wenigstens einem flüssigen und/oder pastösen Auftragsmedium weisen in der Regel einen Auftragskopf auf, der wenigstens eine sich im Wesentlichen über die Breite des Auftragskopf erstreckende Abrisskante umfasst an der das Auftragsmedium den Auftragskopf in Form eines frei fallenden Vorhangs verlässt.Curtain applicator units for coating a moving web of material with at least one liquid and/or pasty application medium generally have an application head which comprises at least one tear-off edge which essentially extends over the width of the application head and at which the application medium leaves the application head in the form of a freely falling curtain .
Um einen möglichst gleichmäßigen Auftrag des Beschichtungsmediums zu gewährleisten, muss eine Störung des dünnen Vorhangs weitgehend vermieden werden. Ebenso muss vermieden werden, dass die Materialbahn bzw. die darauf abgelegte Beschichtung durch andere Störungen wie z.B. Kondenswasser an den Düsenlippen bzw. herabtropfendes Kondenswasser beschädigt wird.In order to ensure that the coating medium is applied as evenly as possible, disruption to the thin curtain must be avoided as far as possible. It must also be avoided that the material web or on it deposited coating is damaged by other disturbances such as condensation on the nozzle lips or dripping condensation.
Ein solcher Vorhang ist insbesondere anfällig für Luftströmungen. Speziell bei Anwendungen, bei denen eine große Vorhanghöhe benötigt oder gewünscht wird, bzw. bei niedrigen Durchflussmengen an Streichfarbe ist der Vorhang besonders empfindlich.Such a curtain is particularly susceptible to air currents. The curtain is particularly sensitive in applications where a large curtain height is required or desired, or with low flow rates of coating color.
Luftströmungen entstehen im Umfeld einer Papiermaschine an vielen Stellen. So wird zum Beispiel durch die Materialbahn selbst Schleppluft mitgeführt, welche den Vorhang stören kann. Zur Entfernung von Schleppströmungen bzw. von Luftgrenzschichten sind aus dem Stand der Technik verschiedene Vorrichtungen zur Luftgrenzschicht-Entfernung bekannt. Exemplarisch seien hierzu die
Jedoch treten auch eine Vielzahl Luftströmungen auf, die nicht durch die bewegte Materialbahn induziert sind. Ursachen solcher Strömungen können bewegte Teile der Maschine sein, aber auch die Hallenbelüftung oder die Bewegungen des Bedienpersonals. Um derartige Luftströmungen vom Vorhang fern zu halten, wurden in der Vergangenheit die Vorhang Auftragswerke eingehaust, wie z.B. in der
In jüngster Zeit wurde auch eine alternative Lösung vorgeschlagen, bei der ein Vorhang Auftragswerk nicht durch eine begehbare Einhausung geschützt wird, sondern durch eine Haube in unmittelbarer Nähe des Auftragskopfes gekapselt ist. Bei einer derartigen Lösung ist jedoch der Auftragskopf durch Bedienpersonal nicht direkt zugänglich. Dazu muss die Haube geöffnet oder entfernt werden. Geschieht dies im laufenden Betrieb, geht dadurch die schützende Wirkung der Haube verloren.Recently, an alternative solution has also been proposed, in which a curtain applicator is not protected by a walk-in enclosure, but is encapsulated by a hood in the immediate vicinity of the applicator head. With such a solution, however, the application head is not directly accessible to operating personnel. To do this, the hood must be opened or removed. If this happens during operation, the protective effect of the hood is lost.
Weiterhin wirken sich bei Vorhangauftragswerken Schwankungen in Temperaturund/oder Luftfeuchtigkeit besonders negativ auf einen stabilen Betrieb aus. Da Auftragswerke im Allgemeinen oftmals räumlich nahe an Trocknungseinrichtungen, wie Zylindertrocknungseinrichtungen und/oder Infrarot-Trocknungseinrichtungen, angeordnet sind, werden solche Auftragswerke oftmals in einer Umgebung mit hoher Umgebungstemperatur kombiniert mit hoher Luftfeuchtigkeit betrieben. Um die Streichfarbe von Vorhangauftragswerken zu entgasen, d.h. um sicher zu stellen, dass die Streichfarbe ohne Luftblasen aus dem Auftragskopf des Vorhangauftragswerks treten kann, werden ferner Vakuumentgasungseinrichtungen eingesetzt, die bei niedriger Temperatur betrieben werden müssen, um ein Sieden der Streichfarbe zu verhindern. Aufgrund der kühlen Streichfarbe, die im Auftragskopf geführt wird, kann die warme Umgebungsluft am Auftragskopf, insbesondere an der Abrisskante des Auftragskopfs, kondensieren und es können Kondensat Tropfen auf die herzustellende Faserstoffbahn fallen bzw. Kondensat Tropfen an der Düsenlippe den flüssigen Vorhang stören und Streifen mit weniger Strich erzeugen. Um dies zu verhindern, werden Vorhangauftragswerke in der Regel in einer diese umgebenden Einhausung oder Kapselung betrieben, welche klimatisiert ist.Furthermore, fluctuations in temperature and/or humidity have a particularly negative effect on stable operation in the case of curtain coaters. Since application units are generally often spatially arranged close to drying devices, such as cylinder drying units and/or infrared drying units, such application units are often operated in an environment with a high ambient temperature combined with high humidity. In order to degas the coating color from curtain coaters, i.e. to ensure that the coating color can exit the application head of the curtain coater without air bubbles, vacuum degassing devices are also used, which must be operated at low temperatures to prevent the coating color from boiling. Due to the cool coating color that is carried in the application head, the warm ambient air can condense on the application head, especially on the separation edge of the application head, and condensate drops can fall onto the fibrous web to be produced or condensate drops on the nozzle lip can disrupt the liquid curtain and cause streaks produce less line. In order to prevent this, curtain application units are generally operated in a housing or encapsulation which surrounds them and is air-conditioned.
Ein wesentlicher Nachteil solcher klimatisierten Einhausungen ist, dass die Klimatisierung sehr teuer ist, sowohl in der Anschaffung wie auch im laufenden Betrieb.A major disadvantage of such air-conditioned housings is that the air-conditioning is very expensive, both to purchase and to operate.
Es ist die Aufgabe der vorliegenden Erfindung eine kostengünstigere Alternative zu einer klimatisierten Einhausung zu finden, mittels der ein Kondensieren der Umgebungsluft am Auftragskopf in ähnlicher oder gleicher Weise wie mit einer Klimatisierung reduziert bzw. unterbunden werden kann, und die trotzdem eine stabilen Betrieb des Vorhangauftragswerks gewährleistet.It is the object of the present invention to find a more cost-effective alternative to an air-conditioned housing, by means of which the ambient air can be condensed on the applicator head in a similar or identical manner as with a Air conditioning can be reduced or prevented, and still ensures stable operation of the curtain coater.
Eine weitere Aufgabe der Erfindung ist es, ein Vorhangauftragswerk vorzuschlagen bei dem der Vorhang selbst bei einer größeren Vorhanghöhe bzw. einer geringeren Auftragsmenge an Auftragsmedium weitgehend unbeeinträchtigt von Luftströmungen bleibt.A further object of the invention is to propose a curtain application unit in which the curtain remains largely unaffected by air currents, even with a greater curtain height or a smaller application quantity of application medium.
Eine weitere Aufgabe der Erfindung ist es, eine einfache Wartung und Kontrolle des Vorhang-Auftragswerks zu ermöglichen, so dass der Vorhang durch die Bewegungen des Bedienpersonals gar nicht oder nur in sehr geringem Maß beeinflusst wird.A further object of the invention is to enable simple maintenance and control of the curtain applicator unit, so that the curtain is not affected at all or only to a very small extent by the movements of the operating personnel.
Eine weitere Aufgabe der Erfindung ist es, eine kompakte und flexible Bauweise für ein Vorhangauftragswerk vorzuschlagen, um auch einen nachträglichen Einbau selbst bei engen Platzverhältnissen und vorgegebener Bahnführung zu ermöglichen.A further object of the invention is to propose a compact and flexible design for a curtain applicator unit, in order to also enable subsequent installation even in the case of cramped space conditions and given web routing.
Diese Aufgaben werden vollständig gelöst durch ein Vorhang-Auftragswerk gemäß dem Kennzeichen des Anspruchs 1 sowie ein Verfahren gemäß dem Kennzeichen des Anspruchs 9.These objects are completely solved by a curtain coater according to the characterizing part of claim 1 and a method according to the characterizing part of claim 9.
Dabei ist ein Vorhang-Auftragswerk vorgesehen zum Auftragen eines flüssigen oder pastösen Auftragsmediums auf zumindest eine Oberfläche einer laufenden Materialbahn, insbesondere einer Faserstoffbahn.In this case, a curtain applicator is provided for applying a liquid or pasty application medium to at least one surface of a running material web, in particular a fibrous web.
Das Vorhang-Auftragswerk umfasst einen Auftragskopf, mit zumindest einer sich im Wesentlichen über die Breite des Auftragskopfes erstreckenden Abrisskante, an der das Auftragsmedium den Auftragskopf in Form eines frei fallenden Vorhangs verlässt. Erfindungsgemäß ist zumindest eine Spüleinrichtung vorgesehen, mittels welcher zumindest eine der zumindest einen Abrisskante mit einem strömenden gasförmigen Spülmedium beaufschlagbar ist.The curtain applicator includes an applicator head with at least one tear-off edge that extends essentially across the width of the applicator head and at which the application medium leaves the applicator head in the form of a freely falling curtain. According to the invention, at least one flushing device is provided, by means of which at least one of the at least one tear-off edge can be subjected to a flowing gaseous flushing medium.
Weiterhin ist zumindest eine Sperrvorrichtung vorgesehen, welche dazu geeignet ist, Luftbewegungen der Umgebungsluft vom Vorhangfern zu halten.Furthermore, at least one blocking device is provided, which is suitable for keeping air movements in the ambient air away from the curtain.
Die erfindungsgemäße Sperrvorrichtung gewährleistet, dass der Vorhang selbst bei einer größeren Vorhanghöhe weitgehend unbeeinträchtigt von Luftströmungen bleibt.The blocking device according to the invention ensures that the curtain remains largely unaffected by air currents, even with a greater curtain height.
Bei der Ausführung sowie der Anordnung der Sperrvorrichtung hat man, wie später noch ausgeführt, vielfältige Möglichkeiten, so dass sich das Vorhang-Auftragswerk so den Gegebenheiten der Einbausituation, des Laufs der Materialbahn etc. anpassen lässt, dass eine Wartung und Kontrolle des Vorhang-Auftragswerks einfach möglich ist, ohne dass der Vorhang durch die Bewegungen des Bedienpersonals signifikant beeinflusst wird.As will be explained later, there are a variety of options for the design and arrangement of the locking device, so that the curtain applicator can be adapted to the conditions of the installation situation, the run of the material web, etc., so that maintenance and inspection of the curtain applicator can be carried out easily possible without the curtain being significantly affected by operator movements.
Dadurch, dass erfindungsgemäß zumindest eine Spüleinrichtung vorgesehen ist, mittels welcher zumindest eine der zumindest einen Abrisskante mit einem strömenden gasförmigen Spülmedium beaufschlagbar ist bzw. beaufschlagt wird, wird erreicht, dass sich im Bereich der Abrisskante wenig oder keine Umgebungsluft ansammeln kann, die an der Abrisskante kondensieren kann.The fact that at least one flushing device is provided according to the invention, by means of which at least one of the at least one tear-off edge can be or is acted upon by a flowing gaseous flushing medium, means that little or no ambient air can collect in the area of the tear-off edge, which is at the tear-off edge can condense.
Durch die Kombination von gespülter Abrisskante und Sperrvorrichtung kann auf eine Klimatisierung komplett verzichtet werden oder eine nur sehr einfache Klimatisierung verwendet werden.The combination of flushed tear-off edge and locking device means that air conditioning can be completely dispensed with or only very simple air conditioning can be used.
Weiterhin kann es durch die Erfindung möglich sein, auf die sonst übliche komplette Einhausung des Vorhang-Auftragswerks zusammen mit einem Teil der laufenden Materialbahn zu verzichten. Dies vereinfacht die Konstruktion und den Einbau des Vorhang-Auftragswerks in eine Beschichtungsanlage signifikant auch bei engen Platzverhältnissen, und reduziert zudem deutlich die anfallenden Kosten. Auch hat die Erfindung eine hohe Flexibilität hinsichtlich der Möglichkeiten der Bahnführung, da viele durch eine feste Einhausung entstehende Einschränkungen der Bahnführung nun wegfallen.Furthermore, the invention can make it possible to dispense with the otherwise customary complete housing of the curtain applicator together with part of the running web of material. This significantly simplifies the design and installation of the curtain applicator unit in a coating system, even when space is limited, and also significantly reduces the costs incurred. The invention also has a high degree of flexibility with regard to the options for web routing, since many of the restrictions on web routing that result from a fixed housing are now eliminated.
Vorteilhafte Ausgestaltungen und Weiterbildungen der Erfindung sind in den Unteransprüchen angegeben.Advantageous refinements and developments of the invention are specified in the dependent claims.
Vorzugsweise umfasst der Auftragskopf wenigstens eine Querverteilkammer sowie einen mit dieser verbunden Düsenspalt mit Austrittsöffnung derart, dass das von der Querverteilkammer über den Düsenspalt zur Austrittsöffnung kommende Auftragsmedium den Auftragskopf an der Austrittsöffnung verlässt, wobei die zumindest eine Abrisskante durch zumindest einen Teil der Austrittsöffnung gebildet ist. Konkret kann in diesem Zusammenhang die Austrittsöffnung eine erste und eine zweite Abrisskante bereitstellen, wobei bei bestimmungsgemäßer Verwendung des Auftragskopfs in Laufrichtung der Materialbahn betrachtet die erste Abrisskante vorne und die zweite Abrisskante hinten angeordnet ist.The application head preferably comprises at least one transverse distribution chamber and a nozzle gap connected thereto with an outlet opening in such a way that the application medium coming from the transverse distribution chamber via the nozzle gap to the outlet opening leaves the application head at the outlet opening, with the at least one tear-off edge being formed by at least part of the outlet opening is. Specifically, in this context, the outlet opening can provide a first and a second tear-off edge, with the first tear-off edge being arranged at the front and the second tear-off edge at the rear when the application head is used as intended, viewed in the running direction of the material web.
Um insbesondere beide Abrisskanten zu spülen und dort ein Kondensieren der Umgebungsluft zu reduzieren oder zu verhindern sieht eine bevorzugte Weiterbildung der Erfindung eine erste und/oder eine zweite Spüleinrichtung vor welche derart angeordnet ist bzw. sind, dass bei bestimmungsgemäßer Verwendung des Auftragskopfs in Laufrichtung der Materialbahn betrachtet, die erste Spüleinrichtung die erste Abrisskante von vorne mit dem Spülmedium beaufschlagt und die zweite Spüleinrichtung die zweite Abrisskante von hinten mit dem Spülmedium beaufschlagt. In einer zu den vorherigen Ausführungsformen alternativen Ausführungsform ist vorgesehen, dass der Auftragskopf wenigstens eine Querverteilkammer und einen mit dieser verbunden Düsenspalt mit Austrittsöffnung sowie eine sich daran anschließende Gleitfläche an die sich wiederum die Abrisskante anschließt derart umfasst, dass in Fließrichtung des Auftragsmediums betrachtet, das von der Querverteilkammer über den Düsenspalt und die Austrittsöffnung kommende Auftragsmedium nach der Austrittsöffnung über die Gleitfläche zur Abrisskante fließt und an der Abrisskante den Auftragskopf verlässt.In order to flush both tear-off edges in particular and to reduce or prevent condensation of the ambient air there, a preferred development of the invention provides a first and/or a second flushing device which is or are arranged in such a way that when the application head is used as intended in the direction of travel of the material web considered, the first flushing device applies the flushing medium to the first tear-off edge from the front and the second flushing device applies the flushing medium to the second tear-off edge from the rear. In an alternative embodiment to the previous embodiments, it is provided that the application head comprises at least one transverse distribution chamber and a nozzle gap connected to it with an outlet opening as well as an adjoining sliding surface, which in turn is adjoined by the tear-off edge in such a way that, viewed in the flow direction of the application medium, the The application medium coming from the transverse distribution chamber via the nozzle gap and the outlet opening flows after the outlet opening over the sliding surface to the tear-off edge and leaves the application head at the tear-off edge.
Konkret kann die zumindest eine Spüleinrichtung außerhalb des Düsenspalts angeordnet sein.Specifically, the at least one flushing device can be arranged outside of the nozzle gap.
Vorzugsweise ist die zumindest eine Spüleinrichtung so ausgebildet und angeordnet, dass die Strömung des gasförmigen Spülmediums in Richtung des frei fallenden Vorhangs gerichtet ist.The at least one flushing device is preferably designed and arranged in such a way that the flow of the gaseous flushing medium is directed in the direction of the freely falling curtain.
Konkret kann der Auftragskopf einen Gehäuseblock, insbesondere aus einem metallischen Werkstoff, umfassen, in dem die Querverteilkammer und der Düsenspalt angeordnet sind, wobei der Gehäuseblock zumindest abschnittweise von einer Außenverkleidung und/oder einer thermisch isolierende Schicht umgeben ist, welche mit der Umgebung in Kontakt kommt.In concrete terms, the application head can comprise a housing block, in particular made of a metallic material, in which the transverse distribution chamber and the nozzle gap are arranged, with the housing block being surrounded at least in sections by an outer covering and/or a thermally insulating layer which comes into contact with the environment .
Bei dem metallischen Werkstoff kann es sich insbesondere um einen Stahl, insbesondere einen legierten oder unlegierten Edelstahl handeln. Die Einteilung der Stähle, bzw. Edelstähle findet sich in der DIN EN 10020.The metallic material can in particular be steel, in particular alloyed or unalloyed stainless steel. The classification of steels and stainless steels can be found in DIN EN 10020.
Weiterhin kann vorgesehen sein, dass der Gehäuseblock ganz oder nur teilweise aus dem metallischen Material, insbesondere dem Stahl besteht. Ein Anteil von mehr als 90 Gew-% kann hierbei aber vorteilhaft sein.Provision can furthermore be made for the housing block to consist entirely or only partially of the metallic material, in particular steel. However, a proportion of more than 90% by weight can be advantageous here.
Die Außenverkleidung kann hierbei bspw. zumindest abschnittweise durch zumindest ein ebenes und/oder gebogenes Blech oder durch zumindest eine ebene und/oder gebogene Kunststoffplatte wie bspw. eine Plexiglasplatte bereitgestellt sein bzw. umfassen.The outer cladding can be provided, for example, at least in sections, by at least one flat and/or curved metal sheet or by at least one flat and/or curved plastic plate such as a plexiglass plate.
Nach einer konkreten Ausgestaltung kann die Außenverkleidung zumindest abschnittweise durch die thermisch isolierende Schicht vom Gehäuseblock thermisch entkoppelt sein. In diesem Fall ist die thermisch isolierende Schicht zumindest abschnittweise zwischen der Außenverkleidung und dem Gehäuseblock angeordnet. Durch die vom Gehäuseblock thermisch entkoppelte Außenverkleidung wird erreicht, dass die Umgebungsluft nicht in direkten Kontakt mit dem "kühlen" Gehäuseblock, durch welchen das Auftragsmedium geführt wird, kommt. Dies hat zum einen den Vorteil, dass die Gefahr der Kondensation am Gehäuseblock reduziert wird. Zum anderen wird auch ein Erwärmen des Gehäuseblocks durch wärmere Umgebungsluft verhindert, wodurch es zu einer Verformung des Gehäuseblocks kommen kann. Aufgrund der hohen Anforderungen an die Genauigkeit z.B. des Düsenspalts können hier selbst kleine Verformungen einen großen Einfluss auf die Qualität der Beschichtung haben. Eine solche Düsenisolierung ermöglicht ein Konstanthalten der Profilqualität der Beschichtung in CD-Richtung.According to a specific embodiment, the outer lining can be thermally decoupled from the housing block at least in sections by the thermally insulating layer. In this case, the thermally insulating layer is arranged at least in sections between the outer cladding and the housing block. The external cladding, which is thermally decoupled from the housing block, ensures that the ambient air does not come into direct contact with the "cool" housing block through which the application medium is guided. On the one hand, this has the advantage that the risk of condensation on the housing block is reduced. On the other hand, the housing block is also prevented from being heated by warmer ambient air, which can result in deformation of the housing block. Due to the high demands on the accuracy, e.g. of the die gap, even small deformations can have a major impact on the quality of the coating. Such nozzle isolation allows the CD profile quality of the coating to be maintained constant.
Nach einer weiteren alternativen Ausgestaltung der Erfindung kann auch die Außenverkleidung zumindest abschnittweise durch eine thermisch isolierende Schicht gebildet sein.According to a further alternative embodiment of the invention, the outer lining can also be formed at least in sections by a thermally insulating layer.
Versuche der Anmelderin haben gezeigt, dass insbesondere durch die Kombination einer - zumindest teilweisen- thermischen Isolierung des Gehäuseblocks mit der Spülung zumindest einer Abrisskante mit einem gasförmigen Spülmedium wie z.B. Luft, ein sehr stabiler Betrieb des Vorhangauftragswerks erreicht werden kann.Tests by the applicant have shown that a very stable operation of the curtain applicator can be achieved in particular through the combination of - at least partial - thermal insulation of the housing block with the flushing of at least one tear-off edge with a gaseous flushing medium such as air.
Es sind verschiedene Möglichkeiten denkbar, wie die thermisch isolierende Schicht aufgebaut sein kann.Various possibilities are conceivable as to how the thermally insulating layer can be constructed.
Nach einer denkbaren Variante umfasst die thermisch isolierende Schicht ein Schaumstoffmaterial und/oder eine Wabenstruktur und/oder Glaswolle und/oder Mineralwolle oder ist durch eines oder mehrere der vorgehenden gebildet.According to a conceivable variant, the thermally insulating layer comprises a foam material and/or a honeycomb structure and/or glass wool and/or mineral wool or is constituted by one or more of the foregoing.
Nach einer weiteren denkbaren Variante ist die thermisch isolierende Schicht durch ein gasförmiges Isolationsmedium gebildet, welches in einem Spalt zwischen dem Gehäuseblock und der Außenverkleidung angeordnet oder geführt ist, wobei insbesondere der Spalt im Bereich der Abrisskante im Bereich 0,5mm - 50mm, bevorzugt 2-10mm, beträgt. In diesem Fall ist es insbesondere von Vorteil, wenn das gasförmige Isolationsmedium zumindest teilweise, vorzugsweise vollständig, durch das strömende gasförmige Spülmedium bereitgestellt ist. In diesem Fall kann auf besonders einfache Art und Weise eine Isolation des Gehäuseblocks sowie eine Spülung der zumindest einen Abrisskante bereitgestellt werden.According to a further conceivable variant, the thermally insulating layer is formed by a gaseous insulating medium which is arranged or guided in a gap between the housing block and the outer paneling, with the gap in the area of the tear-off edge in particular being in the range of 0.5mm - 50mm, preferably 2- 10mm. In this case, it is particularly advantageous if the gaseous insulation medium is provided at least partially, preferably completely, by the flowing gaseous flushing medium. In this case, insulation of the housing block and flushing of the at least one tear-off edge can be provided in a particularly simple manner.
Konkret ist das gasförmige Isolationsmedium und/oder das gasförmige Spülmedium insbesondere Luft, wobei vorgesehen sein kann, dass die Luft vor der Verwendung als Spülmedium und/oder Isolationsmedium hinsichtlich ihrer Temperatur und/oder ihrem Feuchtegehalt konditioniert worden ist.Specifically, the gaseous insulation medium and/or the gaseous flushing medium is, in particular, air, it being possible for the air to be conditioned in terms of its temperature and/or its moisture content before it is used as flushing medium and/or insulation medium.
Hinsichtlich der zumindest einen Sperrvorrichtung ist vorgesehen, dass zumindest eine Sperrvorrichtung in Laufrichtung der Materialbahn vor oder nach dem Auftragskopf angeordnet ist.With regard to the at least one blocking device, it is provided that at least one blocking device is arranged before or after the application head in the running direction of the material web.
Insbesondere können auch zwei oder mehr Sperrvorrichtungen vorgesehen sein, wobei zumindest eine Sperrvorrichtung vor dem Auftragskopf und zumindest eine Sperrvorrichtung nach dem Auftragskopf angeordnet ist.In particular, two or more locking devices can also be provided, with at least one locking device being arranged in front of the application head and at least one locking device being arranged after the application head.
Erfindungsgemäß umfasst die zumindest eine Sperrvorrichtung, insbesondere alle Sperrvorrichtungen Mittel zur Erzeugung eines Luftschildes, insbesondere eine oder mehrere Luftdüsen umfassen.According to the invention, the at least one blocking device, in particular all blocking devices, comprise means for generating an air shield, in particular comprising one or more air nozzles.
Insbesondere kann hierbei vorgesehen sein, dass die Strömungsrichtung der Luft des Luftschildes eine Komponente aufweist, die von dem Auftragskopfweg weist und/oder eine Komponente aufweist, die von der Materialbahn weg weist.In particular, it can be provided here that the flow direction of the air of the air shield has a component that points away from the applicator head and/or has a component that points away from the material web.
Die Sperrwirkung der Sperrvorrichtung wir in diesen Ausführungen dadurch realisiert, dass gezielt eine Luftströmung erzeugt wird, welche jedoch so gerichtet ist, dass sie den Vorhang nicht stört. Die Luftströmung des Luftschildes sollte dabei so stark bemessen sein, dass die Luftbewegungen der Umgebungsluft, welche beispielsweise durch die Bewegung des Bedienpersonals erzeugt werden, nicht, bzw. nur sehr stark abgemildert durch den Luftschild hindurch dringen.In these versions, the blocking effect of the blocking device is realized in that an air flow is generated in a targeted manner, but this is directed in such a way that it does not disturb the curtain. The air flow of the air shield should be dimensioned so strongly that the air movements of the ambient air, which are generated, for example, by the movement of the operating personnel, do not penetrate through the air shield or only penetrate to a very limited extent.
Zur Erfüllung einer größtmöglichen Sperrwirkung wird sich der Luftschild häufig zumindest über die Breite der Materialbahn, bzw. die Breite des Vorhangs erstrecken, oder noch ein wenig darüber hinausgehen.In order to achieve the greatest possible blocking effect, the air shield will often extend at least over the width of the web of material or the width of the curtain, or even go a little beyond that.
Da die benötigten Luftmengen und -geschwindigkeiten je nach Einbau- und Betriebsbedingungen stark unterschiedlich sein können, können in besonders vorteilhaften Ausführungen Mittel zur Steuern bzw. Regeln der Luftmenge und/oder Luftgeschwindigkeit vorgesehen sein. Somit hat der Betreiber die Möglichkeit den Luftschild optimal einzustellen. Die Luftmengen können dabei vorteilhafterweise im Bereich zwischen 0,2 m3/min/m und 12 m3/min/m liegen. Besonders bevorzugt können die Luftmengen zwischen 0,5 m3/min/m und 0,9 m3/min/m liegen. Alternativ können die Luftmengen auch über 1,2 m3/min/m, insbesondere zwischen 2,4 und 9 m3/min/m liegen.Since the required air quantities and speeds can vary greatly depending on the installation and operating conditions, means for controlling or regulating the air quantity and/or air speed can be provided in particularly advantageous embodiments. Thus, the operator has the opportunity to optimally adjust the air shield. The amounts of air can advantageously be in the range between 0.2 m 3 /min/m and 12 m 3 /min/m. The amounts of air can particularly preferably be between 0.5 m 3 /min/m and 0.9 m 3 /min/m. Alternatively, the amounts of air can also be more than 1.2 m 3 /min/m, in particular between 2.4 and 9 m 3 /min/m.
Die Angaben zur Luftmenge sind dabei, sofern nicht explizit anders erwähnt, bei 20°C und 1 bar Druck gemessen.Unless expressly stated otherwise, the information on the air volume is measured at 20°C and 1 bar pressure.
Ein weiterer großer Vorteil dieses Luftschildes ist es, dass das Bedienpersonal zu Reparatur- bzw. Wartungsarbeiten den Luftschild einfach abschalten kann, oder auch einfach durch den Luftschild hindurch greifen kann. Eine gegebenenfalls aufwändige Demontage einer fest installierten starren Vorrichtung kann so entfallen.Another major advantage of this air shield is that the operating personnel can simply switch off the air shield for repair or maintenance work, or can simply reach through the air shield. A possibly complex dismantling of a permanently installed rigid device can thus be omitted.
So kann beispielsweise zur Probennahme von Auftragsmedium aus dem Vorhang ein geeignetes Auffanggefäß oder Probenträger durch den Luftschild hindurch zum Vorhang geführt werden. Hierzu muss weder der Auftragsprozess unterbrochen, noch der Luftschild ausgeschaltet werden.For example, to take samples of application medium from the curtain, a suitable collecting vessel or sample carrier can be guided through the air shield to the curtain. To do this, neither the application process has to be interrupted nor the air shield switched off.
In einer besonders vorteilhaften Ausführung kann vorgesehen sein, dass der Abstand der Sperrvorrichtung zur Auftragskopfweniger als 150cm, insbesondere weniger als 100cm, besonders bevorzugt weniger als 50cm beträgt.In a particularly advantageous embodiment, it can be provided that the distance between the blocking device and the application head is less than 150 cm, in particular less than 100 cm, particularly preferably less than 50 cm.
Hierdurch kann beispielsweise die Gefahr reduziert werden, dass im Raum zwischen dem Sperrwerk und der Vorhang-Auftragswerk Luftbewegungen generiert werden, die sich störend auf den Vorhang auswirken können.In this way, for example, the risk can be reduced that air movements are generated in the space between the barrage and the curtain applicator, which can have a disruptive effect on the curtain.
Insbesondere kann durch eine solche nahe Anordnung vermieden werden, dass sich während des Betriebs Bedienpersonal zwischen der Sperrvorrichtung und dem Vorhang-Auftragswerk aufhalten kann.In particular, such a close arrangement can prevent operating personnel from being between the blocking device and the curtain applicator unit during operation.
Bei Abständen von 50cm und weniger ist es beispielsweise möglich, dass das Bedienpersonal der Maschine durch den Luftschild greifen, und an der Düse bzw. dem Vorhang Arbeiten wie z.B. Probennahme vornehmen kann. Dies ermöglicht ein einfaches Arbeiten des Bedienpersonals, ohne dass durch die Bewegung des Bedienpersonals bzw. die dadurch erzeugten Luftströmungen eine Störung des Betriebs erfolgt.At distances of 50 cm and less, it is possible, for example, that the operating personnel of the machine can reach through the air shield and work on the nozzle or the curtain, such as taking samples. This enables the operating personnel to work easily, without the operation being disrupted by the movement of the operating personnel or the air currents generated thereby.
Es kann sich auch als vorteilhaft erweisen, den Luftschild nicht zu nahe am Auftragskopf anzuordnen. Vorzugsweise kann ein Abstand von 20 cm oder mehr, insbesondere 25 cm oder 30 cm und mehr gewählt werden. Eine derartige Positionierung macht zum einen das Anbringen der Luftdüsen einfacher. Zum anderen kann dadurch auch vermieden werden, dass durch die aufsteigende Luft des Luftschildes ein Sog erzeugt wird, der denn den Vorhang stören kann.It may also be advantageous not to locate the air shield too close to the gun. A distance of 20 cm or more, in particular 25 cm or 30 cm and more, can preferably be selected. Such a On the one hand, positioning makes it easier to attach the air nozzles. On the other hand, it can also be avoided that a suction is generated by the rising air of the air shield, which can then disturb the curtain.
Kommt als Spülmedium Luft zum Einsatz und wird zumindest eine Sperrvorrichtung mittels eines Luftschilds realisiert so kann vorteilhafterweise vorgesehen sein, dass die Spüleinrichtung und die zumindest eine Sperrvorrichtung mit einer gemeinsamen Luftversorgung verbunden sind. Insbesondere kann es sich bei der gemeinsamen Luftversorgung um eine zentrale Druckluftversorgung handeln, die üblicherweise in der Fabrikationshalle ohnehin vorhanden sind.If air is used as the flushing medium and at least one blocking device is implemented by means of an air shield, it can advantageously be provided that the flushing device and the at least one blocking device are connected to a common air supply. In particular, the common air supply can be a central compressed air supply, which is usually present in the production hall anyway.
Eine derartige gemeinsame Luftversorgung reduziert vor allem die Investitionskosten der Anlage.Such a common air supply primarily reduces the investment costs of the system.
Als Alternative zu der zentralen Druckluftversorgung können aber beispielsweise auch Ventilatoren oder Kompressoren als Luftdruckerzeuger für den Luftschild und/oder die Spüleinrichtungen verwendet werden. Es kann dabei unkonditionierte Luft, verwendet werden, die beispielsweise direkt aus der Umgebung des VorhangAuftragswerks entnommen wird. Es können aber auch Einrichtungen zum Konditionieren der Luft, speziell zum Anpassen von Temperatur und Luftfeuchte vorgesehen sein.As an alternative to the central compressed air supply, fans or compressors, for example, can also be used as air pressure generators for the air shield and/or the flushing devices. Unconditioned air can be used, which is taken directly from the vicinity of the curtain applicator, for example. However, devices for conditioning the air, specifically for adjusting the temperature and humidity, can also be provided.
In weiteren vorteilhaften Anwendungen kann vorgesehen sein, dass die Spüleinrichtung bzw. Spüleinrichtungen mit Luft eines höheren Luftdrucks betrieben werden, als der bzw. die Luftschilde. Insbesondere können Spüleinrichtungen mittels der zentralen Druckluftversorgung betrieben werden, während der Luftschild durch einen Ventilator oder Kompressor erzeugt wirdIn further advantageous applications it can be provided that the flushing device or flushing devices are operated with air at a higher air pressure than the air shield or shields. In particular, flushing devices can be operated using the central compressed air supply, while the air shield is generated by a fan or compressor
Ventilatoren sind zum Erzeugen des Luftschilds insbesondere vorteilhaft, da sie effizient und kostengünstig sind. Die Düsen, die mit Kompressoren eingesetzt werden haben üblicherweise Breitschlitz-Spaltweiten von weniger als 0,8 mm. Die Luftdüsen, die mit Ventilatoren zum Erzeugen von Luftschilden betrieben werden, haben üblicherweise Breitschlitz-Spaltweiten von weniger als 3 mm. Luftdüsen mit Kompressoren arbeiten mit höhen statischen Drucken (< 10 bar). Luftdüsen mit Ventilatoren arbeiten üblicherweise mit niedrigem statischen Drucken (< 1 bar).Fans are particularly advantageous for creating the air shield because they are efficient and inexpensive. The nozzles that are used with compressors usually have slot widths of less than 0.8 mm. The air nozzles, which are operated with fans to generate air shields, usually have slot widths of less than 3 mm. air jets with Compressors work with high static pressures (< 10 bar). Air nozzles with fans usually work with low static pressures (< 1 bar).
Dies kann neben ökonomischen Vorteilen durch einen geringeren Luftverbrauch auch ergonomisch vorteilhaft sein, da es z.B. zu einer geringeren Lärmerzeugung durch den Luftschild führt.In addition to economic advantages due to lower air consumption, this can also be ergonomically advantageous, since it leads to less noise being generated by the air shield, for example.
Auch wenn die Spüleinrichtungen und die Luftschilde mit unterschiedlichen Drucklufterzeugern betrieben werden, kann es vorteilhaft sein, dass sie mit demselben Drucklufterzeuger verbindbar sind. So kann es beispielsweise vorteilhaft sein, wenn der Luftschild im Falle eines Ausfalls des Ventilators oder Kompressors auch mit der zentralen Druckluftversorgung verbindbar ist, welche auch die Spüleinrichtungen versorgt, und somit unkompliziert weiter betrieben werden kann. Die Verbindbarkeit kann beispielsweise über einen Absperrhahn oder Ähnliches realisiert sein. Es kann aber auch vorgesehen sein, dass z.B. eine Schlauchverbindung umgesteckt werden muss. Wesentlich ist, dass die Verbindung ohne größere bauliche Maßnahmen schnell hergestellt werden kann.Even if the flushing devices and the air shields are operated with different compressed air generators, it can be advantageous that they can be connected to the same compressed air generator. For example, it can be advantageous if, in the event of a fan or compressor failure, the air shield can also be connected to the central compressed air supply, which also supplies the flushing devices, and can therefore continue to be operated in an uncomplicated manner. The connectivity can be implemented, for example, via a shut-off valve or the like. However, it can also be provided that a hose connection, for example, has to be repositioned. It is essential that the connection can be made quickly without major structural measures.
Vorzugsweise hat das Vorhangauftragswerk Mittel, um die Temperatur des Spülmediums und/oder des Auftragsmediums einzustellen. Dabei ist es vorteilhaft, dass die Temperatur des Spülmediums zwischen der Temperatur der Umgebung und der Temperatur des Auftragsmediums oder auch unterhalb der Temperatur des Auftragsmediums bzw. Unterhalb der Temperatur der Umgebungsluft liegt.The curtain applicator preferably has means for adjusting the temperature of the flushing medium and/or the application medium. It is advantageous that the temperature of the flushing medium is between the temperature of the environment and the temperature of the application medium or below the temperature of the application medium or below the temperature of the ambient air.
Die Mittel sind insbesondere so ausgelegt, um die Temperatur des Spülmediums im Bereich des 0,4-fachen bis 1,5-fachen, bevorzugt des 0,6-fachen bis 1,5-fachen der Temperatur der Umgebung und/oder des Auftragsmediums einzustellen. Die Angaben zu Vielfachen sollen sich hier auf den Temperaturwert in °C beziehen. Eine typische Temperatur des Auftragsmediums kann bei 30°C liegen. Vorteilhaft ist es somit, wenn die Mittel dazu ausgelegt sind, die Temperatur des Spülmediums, insbesondere der Spülluft, im Bereich von 0.4 *30°C= 12°C und 1,5*30°C= 45°C einzustellen.The means are designed in particular to set the temperature of the flushing medium in the range from 0.4 to 1.5 times, preferably from 0.6 to 1.5 times, the temperature of the environment and/or the application medium . The information on multiples should refer to the temperature value in °C. A typical temperature of the application medium can be around 30°C. It is therefore advantageous if the means are designed to set the temperature of the scavenging medium, in particular the scavenging air, in the range of 0.4*30°C=12°C and 1.5*30°C=45°C.
Die Mittel zum Einstellen bzw. aufeinander abstimmen der Temperatur des Spülmediums und/oder der Temperatur des Auftragsmediums können insbesondere Heiz- und/oder Kühleinrichtungen und Temperaturmesseinrichtungen umfassen, mittels der die Temperatur des Spülmediums und des Auftragsmediums gemessen und jeweils auf einen Sollwert eingestellt werden können. Vorzugsweise umfassen die Mittel ferner eine Steuerungs- und/oder Regelungseinrichtung mit welcher automatisch auf Basis der gemessenen Temperaturen des Spülmediums und des Auftragsmediums sowie der Solltemperaturen für das Spülmedium und das Auftragsmedium die Heiz- und/oder Kühleinrichtungen geregelt und/oder gesteuert werden.The means for adjusting or coordinating the temperature of the flushing medium and/or the temperature of the application medium can in particular Include heating and / or cooling devices and temperature measuring devices, by means of which the temperature of the rinsing medium and the application medium can be measured and each set to a desired value. The means preferably also include a control and/or regulation device with which the heating and/or cooling devices are automatically regulated and/or controlled on the basis of the measured temperatures of the rinsing medium and the application medium and the target temperatures for the rinsing medium and the application medium.
Vorzugsweise umfasst das Vorhangauftragswerk Mittel zum Entfeuchten des Spülmediums bzw. um den Feuchtgehalt des Spülmediums zu reduzieren. Hierbei können verschiedene direkte oder indirekte Mittel vorgesehen sein.The curtain applicator preferably includes means for dehumidifying the flushing medium or for reducing the moisture content of the flushing medium. Various direct or indirect means can be provided for this.
So kann beispielsweise eine Entfeuchtungseinrichtung vorgesehen sein, die direkt dem Vorhangauftragswerk, insbesondere der Spüleinrichtung zugeordnet ist.For example, a dehumidifying device can be provided which is assigned directly to the curtain applicator, in particular to the rinsing device.
Es kann jedoch in anderen Ausführungen auch vorgesehen sein, dass es sich bei dem Spülmedium um Luft handelt, die aus dem Druckluftsystem der Fabrik bzw. Werkshalle entnommen wird. Diese Luft wird üblicherweise bereits auf eine gewisse Feuchte und Temperatur hin konditioniert. Je nach Anwendung kann diese für das Druckluftsystem der Fabrik bereits durchgeführte Entfeuchtung der Luft bereits ausreichend sein. In diesem Fall können die Mittel zur Entfeuchtung der Druckluft als indirekte Mittel zur Entfeuchtung dem Vorhangauftragswerk zugerechnet werden.However, in other embodiments it can also be provided that the flushing medium is air which is taken from the compressed air system of the factory or workshop. This air is usually already conditioned to a certain humidity and temperature. Depending on the application, this dehumidification of the air, which has already been carried out for the compressed air system of the factory, can already be sufficient. In this case, the means for dehumidifying the compressed air can be attributed to the curtain applicator as indirect means for dehumidifying.
Weiterhin kann vorteilhafterweise vorgesehen sein, dass das Vorhangauftragswerk Mittel, insbesondere Sensoren zur Bestimmung der Temperatur des Auftragsmediums und/oder der Temperatur des Spülmediums und/oder der relativen Feuchte des Spülmediums umfasst.Furthermore, it can advantageously be provided that the curtain applicator includes means, in particular sensors, for determining the temperature of the application medium and/or the temperature of the rinsing medium and/or the relative humidity of the rinsing medium.
Durch die Erfindung ist es insbesondere möglich, dass das Vorhangauftragswerk keine Einhausung hat. In diesem Fall sind eine besonders kompakte Bauform und eine sehr hohe Flexibilität bei der Führung der Materialbahn möglich.The invention makes it possible in particular for the curtain applicator to have no housing. In this case, a particularly compact design and a very high level of flexibility in guiding the material web are possible.
Alternativ ist denkbar, dass das Vorhangauftragswerk eine Einhausung hat, wobei die Einhausung nicht klimatisiert ist.Alternatively, it is conceivable that the curtain applicator has a housing, with the housing not being air-conditioned.
Durch den Verzicht auf eine Klimatisierung lassen sich sowohl bei der Installation als auch beim Betrieb signifikante Kosten einsparen.By doing without air conditioning, significant costs can be saved both during installation and operation.
In einigen vorliegenden Fällen ist die Einhausung insbesondere so ausgeführt, dass diese zumindest den Auftragskopf und den Bereich umgibt, an dem der Vorhang aus Auftragsmedium auf die Faserstoffbahn trifft.In some of the present cases, the housing is designed in such a way that it surrounds at least the application head and the area where the curtain of application medium meets the fibrous web.
Es kann dabei vorgesehen sein, dass eine solche Einhausung nicht vollständig geschlossen ist, und z.B. nur nach oben oder nach einer Seite offen ist. Da die Einhausung nicht klimatisiert ist, ist die einfach möglich.It can be provided that such a housing is not completely closed and, for example, is only open at the top or on one side. Since the enclosure is not air-conditioned, this is easily possible.
Weiterhin kann vorteilhafterweise vorgesehen sein, dass der Abstand der Öffnung von der Materialbahn zumindest 100mm beträgt. In vielen bevorzugten Anwendungen kann der Abstand zwischen 120 mm und 180 mm betragen. Es können aber auch Abstände von mehr als 200 mm, oder mehr als 300mm vorkommen. Bei einer derartigen Ausführung ist die Fallhöhe des Vorhangs beim Vorhang-Auftrag vergleichsweise sehr groß. Der Vorhang ist hier auch sehr anfällig für Störungen, insbesondere für Luftbewegungen der Umgebungsluft. Die Erfindung kann bei einer solchen Ausführung vorteilhaft eingesetzt werden..Furthermore, it can advantageously be provided that the distance between the opening and the material web is at least 100 mm. In many preferred applications the distance may be between 120mm and 180mm. However, distances of more than 200 mm or more than 300 mm can also occur. With such an embodiment, the drop height of the curtain when the curtain is applied is comparatively very large. The curtain here is also very susceptible to disturbances, especially air movements of the surrounding air. The invention can be used to advantage in such an embodiment.
In einer zu den vorigen Ausführungen alternativen oder zusätzlichen Variante kann beispielsweise vorgesehen sein, dass die zumindest eine Sperrvorrichtung eine Platte umfasst, welche an oder in unmittelbarer Nähe der Auftragskopfbefestigt ist, und sich im Wesentlichen parallel zum Vorhang erstreckt. Eine solche Platte kann in Laufrichtung der Materialbahn betrachtet, vor oder nach dem Vorhang angebracht sein. In einer weiteren, besonders bevorzugten Ausführung kann auch noch eine weitere Platte vorgesehen sein, welche an oder in unmittelbarer Nähe der der Auftragskopfbefestigt ist. In dem Fall wird häufig die eine Platte vor, und die weitere Platte nach dem Vorhang vorgesehen sein.In an alternative or additional variant to the previous versions, it can be provided, for example, that the at least one blocking device comprises a plate which is attached to or in the immediate vicinity of the application head and extends essentially parallel to the curtain. Such a plate can be installed before or after the curtain, viewed in the running direction of the material web. In a further, particularly preferred embodiment, a further plate can also be provided, which is attached to or in the immediate vicinity of the application head. In this case, one plate is often provided in front of the curtain and the other plate is provided after it.
Insbesondere kann vorgesehen sein, dass eine oder beide dieser Platten in einem Abstand zum Vorhang von weniger als 100mm, bevorzugt weniger als 50 mm vorgesehen sind.In particular, it can be provided that one or both of these plates are provided at a distance from the curtain of less than 100 mm, preferably less than 50 mm.
In dieser Ausführung der Erfindung ist eine extrem kompakte Bauweise des Vorhangauftragswerks möglich.In this embodiment of the invention, an extremely compact design of the curtain applicator is possible.
Weiterhin kann das Vorhang-Auftragswerk noch eine Abstreifvorrichtung umfassen, die geeignet ist, mit der Materialbahn mitgeführte Schleppluft vom Vorhang fern zu halten. Eine solche Abstreifvorrichtung kann üblicherweise in Laufrichtung der Materialbahn betrachtet vor dem Auftragskopf angeordnet sein. Als geeignete Abstreifvorrichtungen sind beispielsweise sogenannte Luftmesser (Air-cut) in der Industrie bekannt. Als Alternative dazu - oder gegebenenfalls auch zusätzlichHäufig reicht die Abstreifvorrichtung bis kurz vor den Auftreffpunkt des Vorhangs. Im Gegensatz zu der Sperrvorrichtung wirkt diese Abstreifvorrichtung nur gegen die Luftgrenzschicht in direkter Nähe der bewegten Materialbahn und ist nicht geeignet Luftbewegungen der Umgebungsluft, welche beispielsweise durch die Bewegung des Bedienpersonals oder rotierende Maschinenteile erzeugt werden vom Vorhang fernzuhalten.Furthermore, the curtain applicator unit can also include a scraper device which is suitable for keeping air entrained with the web of material away from the curtain. Such a stripping device can usually be arranged in front of the applicator head, viewed in the running direction of the material web. So-called air knives (air-cut), for example, are known in the industry as suitable stripping devices. As an alternative to this - or possibly also in addition - the scraping device often extends to just before the point of impact of the curtain. In contrast to the locking device, this wiping device only acts against the air boundary layer in the immediate vicinity of the moving material web and is not suitable for keeping air movements in the ambient air, which are caused, for example, by the movement of operating personnel or rotating machine parts, away from the curtain.
Vorzugsweise ist die Außenverkleidung zumindest im Bereich Abrisskante derart angeordnet und ausgebildet ist, dass durch diese der freie Fall des Vorhangs nicht beeinträchtigt wird.The outer lining is preferably arranged and designed in such a way, at least in the area of the tear-off edge, that it does not impair the free fall of the curtain.
Nach einer weiteren konkreten Ausgestaltung der Erfindung umfasst der Gehäuseblock ein erstes und ein zweites Gehäuseblockteil und die Querverteilkammer und der Düsenspalt sind durch einen zwischen den beiden Gehäuseblockteilen gebildeten Hohlraum gebildet. In diesem Zusammenhang sind insbesondere die beiden Gehäuseblockteile durch Verbindungsmittel, insbesondere Schrauben, miteinander verbunden.According to a further specific embodiment of the invention, the housing block comprises a first and a second housing block part and the transverse distribution chamber and the nozzle gap are formed by a cavity formed between the two housing block parts. In this context, in particular the two housing block parts are connected to one another by connecting means, in particular screws.
Ferner ist es insbesondere sinnvoll, wenn der erste Gehäuseblockteil eine erste, die erste Abrisskante bereitstellende Düsenlippe und der zweite Gehäuseblockteil eine zweite, die zweite Abrisskante bereitstellende Düsenlippe umfasst, die relativ zueinander derart verstellbar sind, dass die Weite des Düsenspalts im Bereich der Austrittsöffnung in Querrichtung des Auftragskopfs, und somit in Querrichtung der Faserstoffbahn, individuell einstellbar ist. Durch diese Ausgestaltung lässt sich der erfindungsgemäße Auftragskopf konstruktiv besonders einfach mit verstellbarem Düsenspalt aufbauen.Furthermore, it is particularly useful if the first housing block part comprises a first nozzle lip providing the first tear-off edge and the second housing block part comprises a second nozzle lip providing the second tear-off edge, which can be adjusted relative to one another in such a way that the width of the die gap in the region of the outlet opening is in the transverse direction of the application head, and thus in the transverse direction of the fibrous web, is individually adjustable. This configuration allows the application head according to the invention structurally particularly simple to build with an adjustable nozzle gap.
Nach einer weiteren bevorzugten konkreten Ausgestaltung der Erfindung hat der Auftragskopf eine Oberseite und eine Unterseite und die Austrittsöffnung ist an der Unterseite angeordnet. In diesem Fall ist es insbesondere sinnvoll, wenn das zumindest teilweise das Isolationsmedium bereitstellende Spülmedium in einer von der Oberseite zur Unterseite gerichteten Strömungsrichtung, insbesondere von der Oberseite zur Unterseite, zum Bereich der Abrisskante strömt.According to a further preferred specific embodiment of the invention, the applicator head has an upper side and an underside and the outlet opening is arranged on the underside. In this case, it is particularly useful if the flushing medium that at least partially provides the insulating medium flows in a flow direction directed from the top to the bottom, in particular from the top to the bottom, to the area of the tear-off edge.
Das konditionierte Spülmedium (z.B. Luft) sollte eine geeignete Feuchte und eine geeignete Temperatur aufweisen, so dass die Bildung von Kondenswasser z.B. auf die Lippen des Auftragskopfes oder dessen Abriss Kante sicher vermieden bzw. eliminiert werden kann.The conditioned rinsing medium (e.g. air) should have a suitable humidity and a suitable temperature so that the formation of condensation, e.g. on the lips of the application head or its tear-off edge, can be reliably avoided or eliminated.
Hinsichtlich des Verfahrens wird die Aufgabe gelöst durch ein Verfahren gemäß Anspruch 9.With regard to the method, the object is achieved by a method according to claim 9.
Vorteilhafte Ausgestaltungen des Verfahrens sind in den Unteransprüchen beschrieben.Advantageous refinements of the method are described in the dependent claims.
Prinzipiell können alle vorgehend beschriebenen Sperrvorrichtungen für die Verwendung in Verfahren gemäß einem Aspekt der Erfindung geeignet.In principle, all locking devices described above are suitable for use in methods according to one aspect of the invention.
Es ist vorgesehen, dass das Vorhang-Auftragswerk eine Sperrvorrichtung umfasst, welche wiederum Mittel zur Erzeugung eines Luftschildes umfasst. Die können insbesondere eine oder mehrere Luftdüsen sein. Die Geschwindigkeit der Luft des Luftschildes kann in besonders vorteilhaften Ausführungen zwischen 10 m/s und 60 m/s , insbesondere zwischen 20 m/s und 50 m/s betragen.It is provided that the curtain applicator includes a blocking device, which in turn includes means for generating an air shield. In particular, they can be one or more air nozzles. In particularly advantageous embodiments, the speed of the air of the air shield can be between 10 m/s and 60 m/s, in particular between 20 m/s and 50 m/s.
Vorteilhafte Luftmengen können dabei im Bereich zwischen 0,2 m3/min/m und 1,2 m3/min/m liegen. Insbesonere können die Luftmengen zwischen 0,5 m3/min/m und 0,9 m3/min/m liegen.Advantageous amounts of air can be in the range between 0.2 m 3 /min/m and 1.2 m 3 /min/m. In particular, the amounts of air can be between 0.5 m 3 /min/m and 0.9 m 3 /min/m.
Auch größere Luftmengen können jedoch vorteilhaft sein. So haben beispielsweise Versuche der Anmelderin gezeigt, dass Luftmengen über 1,2 m3/min/m, insbesondere zwischen 2,4 und 12 m3/min/m sehr vorteilhafte Resultate und stabile Luftschilde liefern.However, larger amounts of air can also be advantageous. For example, tests by the applicant have shown that air quantities of more than 1.2 m 3 /min/m, in particular between 2.4 and 12 m 3 /min/m, provide very advantageous results and stable air shields.
Vorteilhafterweise kann der Luftschild mittels einer Schlitzdüse erzeugt werden, die eine Schlitzbreite zwischen 1mm und 5mm, insbesondere zwischen 2mm und 4mm aufweist.The air shield can advantageously be produced by means of a slit nozzle which has a slit width of between 1 mm and 5 mm, in particular between 2 mm and 4 mm.
Beispielhaft sind in der folgende Tabelle einige vorteilhafte Luftmengen und Geschwindigkeiten aufgeführt, die mittels eine Schlitzdüse erzeugt werden können.(Alle Werte bezogen auf eine Breite von 1 m).
Die Werte der obigen Tabelle sollen die Erfindung lediglich illustrieren, stellen aber in keiner Weise eine Beschränkung dar.The values of the above table are only intended to illustrate the invention, but do not represent a limitation in any way.
Je nach Anwendung kann dabei auch vorgesehen sein, dass die für den Luftschild verwendete Luft aufbereitet wird. Die Aufbereitung kann beispielsweise ein Filtern und/oder Entfeuchten und/oder Erwärmen bzw. Abkühlen umfassen.Depending on the application, it can also be provided that the air used for the air shield is processed. The processing can include, for example, filtering and/or dehumidifying and/or heating or cooling.
Eine vorteilhafte Ausführung des Verfahrens ist dadurch gekennzeichnet, dass durch den Auftragskopf das Auftragsmedium mit einer Durchflussrate von weniger als 10 l/min*m, insbesondere von weniger als 6 l/min*m, besonders bevorzugt zwischen 2 l/min*m und 5 l/min*m aufgetragen wird. Hierdurch wird ein vergleichsweise dünner Vorhang erzeugt, welcher besonders leicht durch Luftbewegungen der Umgebungsluft beeinflusst werden kann. Hier ist die Verwendung einer erfindungsgemäßen Vorhang-Auftragsvorrichtung mit einer Sperrvorrichtung besonders vorteilhaft. Insbesondere auch dann, wenn die Fallhöhe des Vorhangs mehr als 100mm, mehr als 200 mm, oder auch 300mm und mehr beträgt.An advantageous embodiment of the method is characterized in that the application medium is fed through the application head at a flow rate of less than 10 l/min*m, in particular less than 6 l/min*m, particularly preferably between 2 l/min*m and 5 l/min*m is applied. This creates a comparatively thin curtain, which can be particularly easily influenced by air movements in the ambient air. The use of a curtain application device according to the invention with a blocking device is particularly advantageous here. Especially when the drop height of the curtain is more than 100mm, more than 200mm, or 300mm and more.
Es kann aber auch vorteilhaft sein, das Auftragsmedium mit einer größeren Durchflussrate aufzutragen, beispielsweise 20 l/min*m, 25 l/min*m oder mehr. Auf diese Weise lassen sich auch Auftragsmengen von 20 g/m2 oder gar 30 g/m2 realisierenHowever, it can also be advantageous to apply the application medium at a higher flow rate, for example 20 l/min*m, 25 l/min*m or more. In this way it is also possible to apply quantities of 20 g/m 2 or even 30 g/m 2
In einer weiteren vorteilhaften Ausführung des Verfahrens kann vorgesehen sein, dass die Materialbahn mit einer Geschwindigkeit von zwischen 100 m/min und 1200 m/min, insbesondere zwischen 200 m/min und 800 m/min bewegt wird. Um bei diesen Geschwindigkeiten auch geringe Auftragsmengen pro Flächeneinheit realisieren zu können, müssen die Zusammensetzung und/oder die Dicke des Vorhangs entsprechend angepasst werden, was den Vorhang auch wiederum anfälliger für Umgebungsluft macht. Hier ist die Verwendung einer erfindungsgemäßen Vorhang-Auftragsvorrichtung mit einer Sperrvorrichtung wieder besonders vorteilhaft. Das Verfahren kann jedoch auch vorteilhaft bei Geschwindigkeiten über 800 m/min, z.B. bei 1000 m/min, 1200 m/min, 1500 m/min oder mehr eingesetzt werdenIn a further advantageous embodiment of the method it can be provided that the material web is moved at a speed of between 100 m/min and 1200 m/min, in particular between 200 m/min and 800 m/min. In order to be able to apply small application quantities per unit area at these speeds, the composition and/or the thickness of the curtain must be adjusted accordingly, which in turn also makes the curtain more susceptible to ambient air. Here the use of a curtain application device according to the invention with a blocking device is again particularly advantageous. However, the method can also be used advantageously at speeds above 800 m/min, for example at 1000 m/min, 1200 m/min, 1500 m/min or more
Zur Bedeutung der Durchflussmenge sei auf die folgende Tabelle 1 verwiesen. Beispielhaft sind hie für eine Streichfarbe als Auftragsmedium mit einem typischen Feststoffgehalt von 63% die notwendigen Durchflussmengen in Anhängigkeit von der Produktionsgeschwindigkeit und dem gewünschten Strichgewicht angegeben.
In Tabelle 1 ist deutlich erkennbar, dass es für einen breiten Bereich von Anwendungen sehr wichtig ist, einen Auftrag von niedrigen Durchflussmengen stabil realisieren zu können. Unter anderem für die in Tabelle 1 gezeigten Ausführungen ist die Erfindung sehr vorteilhaft, insbesondere, aber nicht ausschließlich in Kombination mit einer Höhe des Vorhangs von 100mm oder mehr.Table 1 clearly shows that it is very important for a wide range of applications to be able to stably implement application of low flow rates. Among other things, the invention is very advantageous for the embodiments shown in Table 1, particularly but not exclusively in combination with a curtain height of 100mm or more.
Die hier gezeigten Strichgewichte zwischen 8 g/m2 und 14 g/m2 sind durchaus üblich. Jedoch können mit dem erfindungsgemäßen Verfahren bzw. der erfindungsgemäßen Vorrichtung auch Strichgewichte von bis zu 20 g/m2 oder mehr realisiert werden.The coat weights shown here between 8 g/m 2 and 14 g/m 2 are quite common. However, coat weights of up to 20 g/m 2 or more can also be realized with the method according to the invention and the device according to the invention.
Bei dem gasförmigen Spülmedium kann es sich insbesondere um Luft handeln. Wird in der weiteren Beschreibung dieses Verfahrens von einem Spülmedium gesprochen, so ist damit immer das gasförmige Spülmedium gemeint, solange nicht explizit etwas anderes erwähnt wird.The gaseous flushing medium can in particular be air. If a flushing medium is mentioned in the further description of this method, this always means the gaseous flushing medium, unless something else is explicitly mentioned.
Das Spülmedium (z.B. Luft) sollte eine geeignete Feuchte und eine geeignete Temperatur aufweisen, so dass die Bildung von Kondenswasser z.B. auf die Lippen des Auftragskopfes oder dessen Abriss Kante sicher vermieden bzw. eliminiert werden kann.The rinsing medium (e.g. air) should have a suitable humidity and a suitable temperature so that the formation of condensation, e.g. on the lips of the application head or its tear-off edge, can be reliably avoided or eliminated.
Generell kann die Temperatur des Spülmediums kleiner, größer oder gleich der Temperatur des Auftragsmediums sein.In general, the temperature of the flushing medium can be lower, higher or equal to the temperature of the application medium.
Eine bevorzugte Ausgestaltung des Verfahrens sieht vor, dass die Temperatur des Spülmediums zwischen der Temperatur der Umgebung und der Temperatur des Auftragsmediums gehalten wird.A preferred embodiment of the method provides that the temperature of the flushing medium is kept between the temperature of the environment and the temperature of the application medium.
Eine alternative, vorteilhafte Ausgestaltung des Verfahrens sieht vor, dass die Temperatur des Spülmediums leicht, beispielsweise weniger als 10°K, speziell 7°K oder 5°K, unterhalb der Temperatur des Auftragsmediums und/oder Unterhalb der Temperatur der Umgebungsluft liegt.An alternative advantageous embodiment of the method provides that the temperature of the flushing medium is slightly, for example less than 10°K, specifically 7°K or 5°K, below the temperature of the application medium and/or below the temperature of the ambient air.
Denkbar ist in diesem Zusammenhang insbesondere, dass die Temperatur des Spülmediums im Bereich von 8°C bis 55°C, bevorzugt von 18°C bis 40°C, die des Auftragsmediums im Bereich von 18°C bis 40°C, bevorzugt 25°C bis 35°C und die Temperatur der Umgebung kleiner 65°C ist.In this context, it is particularly conceivable that the temperature of the rinsing medium is in the range from 8°C to 55°C, preferably from 18°C to 40°C, and that of the application medium in the range from 18°C to 40°C, preferably 25° C to 35°C and the ambient temperature is less than 65°C.
Bevorzugt weicht die Temperatur des Spülmediums um bis zu 7°K, besonders bevorzugt um maximal 5°K, nach unten oder nach oben von der Temperatur des Auftragsmediums ab.The temperature of the flushing medium preferably deviates by up to 7°K, particularly preferably by a maximum of 5°K, down or up from the temperature of the application medium.
In besonders bevorzugten Ausführungen des Verfahrens kann vorgesehen sein, dass die Temperatur des Spülmediums größer ist, als die Temperatur des Auftragsmediums. Insbesondere kann die Temperatur des Spülmediums zwischen 4° K und 25°K, speziell zwischen 7°K und 15°K größer sein, als die Temperatur des Auftragsmediums.In particularly preferred versions of the method, it can be provided that the temperature of the flushing medium is greater than the temperature of the application medium. In particular, the temperature of the flushing medium can be between 4°K and 25°K, specifically between 7°K and 15°K higher than the temperature of the application medium.
Um beispielsweise unerwünschte Kondensation, speziell an der Abrisskante zu vermeiden kann vorteilhafterweise vorgesehen sein, dass die relative Feuchte des Spülmediums kleiner als 100 RH% ist. Besonders vorteilhafterweise kann vorgesehen sein, dass die relative Feuchte des Spülmediums kleiner als 80 %RH oder kleiner als 70 %RH ist.In order to avoid unwanted condensation, for example, especially at the tear-off edge, it can advantageously be provided that the relative humidity of the flushing medium is less than 100 RH%. Particularly advantageously, it can be provided that the relative humidity of the flushing medium is less than 80% RH or less than 70% RH.
Ganz besonders vorteilhaft ist es auch zur Verhinderung von Kondensation, wenn die Temperatur und der Feuchtegehalt des Spülmediums sowie die Temperatur des Auftragsmediums aufeinander abgestimmt sind.It is also very particularly advantageous to prevent condensation if the temperature and the moisture content of the rinsing medium and the temperature of the application medium are matched to one another.
In vielen Fällen wird die Temperatur des Gehäuseblocks im Wesentlichen der Temperatur des Auftragsmediums entsprechen. (Evtl. mit 1° K , 2°K oder maximal 5°K Unterschied). Die Abrisskante wird dann dieselbe Temperatur annehmen.In many cases the temperature of the housing block will essentially correspond to the temperature of the application medium. (Possibly with a difference of 1°K, 2°K or a maximum of 5°K). The tear-off edge will then assume the same temperature.
In Anwendungen, in denen die Temperatur des Spülmediums, z.B. der Spülluft, höher ist, als die des Auftragsmediums, wird das Spülmedium beim Anströmen der Abrisskante bzw. der übrigen Teile des Gehäuseblocks in Richtung der Temperatur des Auftragsmediums herunter gekühlt. Dadurch erhöht sich die relative Feuchte des Spülmediums. Sinkt die Temperatur des Spülmediums unter den Taupunkt, so kann es zu unerwünschter Kondensation kommen.In applications in which the temperature of the rinsing medium, for example the rinsing air, is higher than that of the application medium, the rinsing medium is inflowing with the Tear-off edge or the other parts of the housing block cooled down in the direction of the temperature of the application medium. This increases the relative humidity of the flushing medium. If the temperature of the flushing medium falls below the dew point, unwanted condensation can occur.
Diesem Umstand kann in vorteilhaften Ausführungen Rechnung getragen werden, indem die Feuchtebeladung des Spülmediums derart gering gehalten wird -ggf. durch eine vorgeschaltete Entfeuchtung- dass diese Kondensation an den Düsenlippen und/oder den Abrisskanten vermieden werden.This circumstance can be taken into account in advantageous embodiments in that the moisture content of the flushing medium is kept so low - if necessary. through an upstream dehumidification that this condensation on the nozzle lips and/or the tear-off edges is avoided.
Insbesondere kann vorgesehen sein, dass die Temperatur des Spülmediums größer ist, als die Temperatur des Auftragsmediums, und der Feuchtegehalt des Spülmediums so eingestellt ist, dass der Taupunkt des Spülmediums über der Temperatur des Auftragsmediums, insbesondere mehr als 2° K über der Temperatur des Auftragsmediums liegt.In particular, it can be provided that the temperature of the rinsing medium is greater than the temperature of the application medium, and the moisture content of the rinsing medium is adjusted in such a way that the dew point of the rinsing medium is above the temperature of the application medium, in particular more than 2° K above the temperature of the application medium lies.
Die relative Feuchte des Spülmediums bleibt dann auch nach Abkühlen an der Abrisskante soweit unter 100% RH, beispielsweise bei 80%RH, 70%RH oder weniger, so dass keine Kondensation an der Düsenlippen oder an der Abrisskannte entsteht.The relative humidity of the flushing medium then remains well below 100% RH, for example at 80% RH, 70% RH or less, even after cooling at the tear-off edge, so that no condensation occurs on the nozzle lips or on the tear-off edge.
Um eine effektive Spülung der Abrisskante zu erhalten sowie gleichzeitig auch einen stabilen Vorhang zu gewährleisten, kann vorteilhafterweise vorgesehen sein dass die Ausströmgeschwindigkeit des Spülmediums zwischen 6 m/min und 40 m/min, insbesondere zwischen 12 m/min und 20 m/min beträgt
Zusätzlich oder alternativ kann auch vorgesehen sein, dass die Austrittsgeschwindigkeit des Auftragsmediums aus dem Auftragskopf zwischen 10 m/min und 200 m/min, insbesondere zwischen 16 m/min und 66 m/min beträgt. Ähnlich wie bei Temperatur und Feuchtigkeit bringt es wieder große Vorteile, wenn die Ausströmgeschwindigkeit des Spülmediums und die Austrittsgeschwindigkeit des Auftragsmediums aufeinander abtgestimmt sind.In order to obtain effective flushing of the tear-off edge and at the same time to ensure a stable curtain, it can advantageously be provided that the outflow speed of the flushing medium is between 6 m/min and 40 m/min, in particular between 12 m/min and 20 m/min
In addition or as an alternative, it can also be provided that the exit speed of the application medium from the application head is between 10 m/min and 200 m/min, in particular between 16 m/min and 66 m/min. Similar to temperature and humidity, there are great advantages when the outflow speed of the flushing medium and the exit speed of the application medium are coordinated.
Insbesondere kann vorgesehen sein, dass die Ausströmgeschwindigkeit des Spülmediums zwischen 40% und 140%, insbesondere zwischen 50% und 100% der Austrittsgeschwindigkeit des Auftragsmediums beträgt.In particular, it can be provided that the outflow speed of the flushing medium is between 40% and 140%, in particular between 50% and 100% of the exit speed of the application medium.
Üblicherweise wird es für die Stabilität des Vorhangs eher vorteilhaft sein, wenn die Ausströmgeschwindigkeit des Spülmediums kleiner oder maximal gleich groß ist, wie die Austrittsgeschwindigkeit des Auftragsmediums.It will usually be more advantageous for the stability of the curtain if the outflow speed of the flushing medium is less than or at most the same as the exit speed of the application medium.
Die folgende Tabelle gibt noch einmal einen Überblick über die vorteilhaften Bereiche einiger Verfahrensparameter sowie einige exemplarische Beispiele für mögliche Realisierungen solcher Verfahren. Die Parameterwerte wurden speziell für eine Ausführung mittels eines Vorhang-Auftragswerks ermittelt, das eine Sperrvorrichtung umfasst, die Mittel zur Erzeugung eines Luftschildes aufweist.
Es sei angemerkt, dass die Erfindung nicht auf die in der Tabelle angegebenen, vorteilhaften Parameterbereiche beschränkt ist.It should be noted that the invention is not limited to the advantageous parameter ranges given in the table.
Im Folgenden wird die Erfindung anhand schematischer, nicht maßstäblicher Figuren näher erläutert.The invention is explained in more detail below using schematic figures that are not to scale.
Die
Dabei benötigt die Einhausung 30 einen relativen großen Bauraum. Zudem ist die notwendige Klimatisierung in Anschaffung und Betrieb mit erheblichen Kosten verbunden.The
Die Materialbahn 4 bewegt sich dabei in Maschinenrichtung MD von links nach rechts. Der Auftrag erfolgt hier zwischen zwei Umlenkwalzen 3, über die die Materialbahn geführt wird. Dies ist für die Erfindung jedoch nicht notwendig. Der Auftrag kann beispielsweise auch an einer Walze erfolgen. In Laufrichtung der Materialbahn 4 gesehen vor dem Vorhang 2 ist eine Abstreifvorrichtung 5 vorgesehen. Sie kann beispielsweise als sogenannter Air-cut ausgeführt sein. Alternativ kann aber beispielsweise auch vorgesehen sein, dass die Abstreifvorrichtung 5 eine Bürste, Folie oder Lippe umfasst, bzw. daraus besteht, die an die Materialbahn 4 angelegt werden kann. Beide Ausführungen können die wichtige Funktion der Abstreifvorrichtung 5 erfüllen, nämlich die von der Materialbahn 4 mitgeführte Luftgrenzschicht zu reduzieren bzw. zu entfernen.The
Das Vorhang-Auftragswerk in
Auf eine Einhausung des Vorhang-Auftragswerks kann hier ebenso verzichtet werden, wie auf eine Klimatisierung der Umgebung des Auftragskopfes. Dadurch können die Anschaffungskosten ebenso wie die Betriebskosten reduziert werden. Ebenso kann man in
Das in
In
In
Bei der in
Die
Der Auftragskopf 1 hat eine Querverteilkammer 23 sowie einen mit dieser verbunden Düsenspalt 24 mit Austrittsöffnung 25 derart, dass das von der Querverteilkammer 23 über den Düsenspalt 24 zur Austrittsöffnung 25 kommende Auftragsmedium den Auftragskopf 1 an der Austrittsöffnung 25 verlässt.The application head 1 has a
Vorliegend stellt die Austrittsöffnung 25 eine in Bahnlaufrichtung MD betrachtete vordere Abrisskante 26 sowie eine in Bahnlaufrichtung MD betrachtete hintere Abrisskante 27 bereit.In the present case, the
Wie aus der Darstellung der
Der Auftragskopf 1 umfasst einen Gehäuseblock aus einem metallischen Werkstoff, vorteilhafterweise einem Stahl, in dem die Querverteilkammer 23 und der Düsenspalt 24 angeordnet sind. Der Gehäuseblock umfasst ein erstes Gehäuseblockteil 10 (in der vorliegenden Ausführungsform vorderes Gehäuseblockteil 10) und ein zweites Gehäuseblockteil 11 (in der vorliegenden Ausführungsform hinteres Gehäuseblockteil 11), wobei durch einen zwischen den beiden Gehäuseblockteilen 10, 11 gebildeten Hohlraum die Querverteilkammer 23 und der Düsenspalt 24 gebildet sind. Wie aus der Darstellung der
Im vorliegenden Ausführungsbeispiel ist der Gehäuseblock abschnittweise von einer Außenverkleidung 12.1, 12.2 umgeben, welche mit der Umgebung in Kontakt kommt. Die Außenverkleidung 12.1, 12.2 weist hierbei einen in Bahnlaufrichtung MD vorderen Teil der Außenverkleidung 12.1 in Form eines gebogenen Blechs sowie einen in Bahnlaufrichtung MD hinteren Teil der Außenverkleidung 12.2 in Form eines gebogenen Blechs auf. Wie ferner zu erkennen ist, ist die Außenverkleidung 12.1, 12.2 im Bereich Abrisskanten 26, 27 derart angeordnet und ausgebildet, dass durch diese der freie Fall des Vorhangs 2 nicht beeinträchtigt wird.In the present exemplary embodiment, the housing block is partially surrounded by an outer covering 12.1, 12.2, which comes into contact with the environment. The outer cladding 12.1, 12.2 has a part of the outer cladding 12.1 in the form of a bent sheet metal at the front in the web running direction MD and a part of the outer cladding 12.2 in the form of a bent sheet metal at the rear in the web running direction MD. As can also be seen, the outer covering 12.1, 12.2 is arranged and designed in the area of the tear-off
Die Außenverkleidung 12 ist zumindest abschnittweise durch eine thermisch isolierende Schicht vom Gehäuseblock 10, 11 thermisch entkoppelt.The outer covering 12 is thermally decoupled from the
Vorliegend ist die thermisch isolierende Schicht zwischen dem vorderen Teil der Außenverkleidung 12.1 und dem vorderen Gehäuseblockteil 10 durch ein gasförmiges Isolationsmedium gebildet, welches in einem Spalt zwischen dem vorderen Gehäuseblockteil 10 und dem vorderen Teil der Außenverkleidung 12.1 geführt ist und durch das strömende gasförmige Spülmedium 13 aus der ersten Spüleinrichtung 28 bereitgestellt ist. Ferner ist vorliegend der in der
In beiden Fällen, d.h. in Bezug zur ersten Spüleinrichtung 28 und zur zweiten Spüleinrichtung 29, strömt das Spülmedium in einer von der Oberseite zur Unterseite gerichteten Strömungsrichtung zu den beiden Abrisskanten 26, 27.In both cases, i.e. in relation to the
Für die folgende Diskussion der
Die
Die
Der Auftragskopf der
Als weiterer Unterschied zur
Die
Der Auftragskopf 1 der
Die
Der Auftragskopf 1 der
Die
Der Auftragskopf 1 der
An der Abrisskante 16 sind zwei Spüleinrichtungen 28, 29 vorgesehen, mittels denen mittels die Abrisskante 16 mit dem strömenden gasförmigen Spülmedium 13, 14 beaufschlagbar ist.Two
Die
Der Auftragskopf 1 der
Claims (13)
- Curtain applicator for applying a liquid or pasty application medium to at least one application medium onto at least one surface of a moving material web (4), in particular a fibrous web (4), the curtain applicator comprising comprises an applicator head (1) with at least one application unit extending substantially over the width of the applicator head (1). The width of the applicator head (1), at which the application medium the application medium leaves the application head (1) in the form of a freely falling curtain (2). Curtain (2), at least one rinsing device (28, 29) being provided, by means of which at least one of the is provided, by means of which at least one of the at least one tear-off edge (16, 26, 27) with a flowing gaseous flushing medium (13, 14), and in that furthermore at least one blocking device (9) is provided (9) is provided, which is suitable for preventing air movements of the air away from the curtain (2), characterized in that in that the at least one blocking device (9) is arranged in the running direction of the material web (4) is arranged upstream and/or downstream of the application head (1) and the at least one blocking device (9) comprises means for generating an air shield (9), in particular one or more air nozzles (6).
- Curtain applicator according to claim 1, characterized in that the application head (1) comprises a housing block (10, 10', 11, 11'), in particular of a metallic of a metallic material, in which a transverse distribution chamber (23, 23.1, 23.2) and a nozzle gap (24, 24.1, 24.2) are arranged, and the housing block (10, 10', 11. 11') is covered at least in sections by an (12.1, 12.2) and/or a thermally insulating layer, which is in contact with the environment. which comes into contact with the environment.
- Curtain applicator according to claim 2, characterized in that the outer cladding (12.1, 12.2) is at least partially separated from the housing block (10.1, 12.2) by the thermally insulating layer. Thermally decoupled from the housing block (10, 10', 11, 11') by the thermally is thermally decoupled.
- Curtain applicator according to one of the previous claims, characterized in that the flow direction of the air of the air shield (9) has a component pointing away from the applicator head (1) and/or has a component pointing away from the material web (4).
- 5th curtain applicator according to one of the previous claims, characterized in that the distance of at least one barrier device (9, 9a, 9b), in particular of all barrier devices (9, 9a, 9b) from the applicator head (1) is less than 100 cm, in particular less than 50 cm, particularly preferably between 20 cm and 50 cm.
- Curtain applicator according to one of the previous claims, characterized in that the flushing device (28, 29) and the at least one blocking device (9) are connected or connectable to a common air supply.
- Curtain applicator according to one of the previous claims, characterized in that means are provided for adjusting the temperature of the gaseous rinsing medium (13, 14) and/or of the application medium, the means being set up in particular to adjust the temperature of the rinsing medium (13, 14) in the range of 0.4 to 1.5 times the temperature of the environment and/or of the application medium.
- Curtain applicator according to one of the preceding claims, characterized in that means are provided to reduce the moisture content of the rinsing medium (13, 14).
- Method for coating a running material web (4) with at least one liquid and/or pasty application medium by means of a curtain applicator, in particular a curtain applicator according to one of the previous claims, wherein the application medium leaves the application head (1) in the form of a freely falling, single-layer or multilayer curtain (2) which subsequently steps onto the material web (4), wherein the region of at least one of the at least one tear-off edges (26, 27) is acted upon by a flowing gaseous flushing medium (13, 14), characterized in that the curtain applicator comprises a barrier device (9) which comprises means for generating an air shield (9) and the velocity of the air of the air shield (9) is between 15 m/s and 60 m/s..
- Method according to claim 9, characterized in that the application medium is applied at a flow rate of less than 10 l/min*m, in particular of less than 6 l/min*m, more preferably between 2 l/min*m and 5 l/min*m.
- Process according to any one of claims 9 to 10, characterized in that the relative humidity of the rinsing medium is less than 100 RH%.
- Process according to one of claims 9 to 11, characterized in that the outflow speed of the (13, 14) rinsing medium is between 6 m/min and 40 m/min, in particular between 12 m/min and 20 m/min, and/or in that the exit speed of the application medium from the application head (1) is between 10 m/min and 100 m/min, in particular between 16 m/min and 66 m/min.
- Process according to any one of claims 9 to 12, characterized in that air quantities between 2.4 m3/min/m and 12 m3/min/m are used to generate the air shield (9).
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE102017124280.5A DE102017124280A1 (en) | 2017-10-18 | 2017-10-18 | Curtain coater and method for applying a coating medium |
PCT/EP2018/076779 WO2019076627A1 (en) | 2017-10-18 | 2018-10-02 | Curtain application unit and method for applying an application medium |
Publications (2)
Publication Number | Publication Date |
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EP3697543A1 EP3697543A1 (en) | 2020-08-26 |
EP3697543B1 true EP3697543B1 (en) | 2023-03-29 |
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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EP18782395.0A Active EP3697543B1 (en) | 2017-10-18 | 2018-10-02 | Curtain application unit and method for applying an application medium |
Country Status (7)
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US (1) | US11434607B2 (en) |
EP (1) | EP3697543B1 (en) |
CN (1) | CN111246944B (en) |
DE (1) | DE102017124280A1 (en) |
FI (1) | FI3697543T3 (en) |
PL (1) | PL3697543T3 (en) |
WO (1) | WO2019076627A1 (en) |
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Publication number | Priority date | Publication date | Assignee | Title |
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DE102017101373B4 (en) * | 2017-01-25 | 2022-02-03 | Voith Patent Gmbh | Curtain applicator and method for applying an application medium |
DE102021113804A1 (en) | 2021-05-28 | 2022-05-05 | Voith Patent Gmbh | coater nozzle |
DE102022105518B4 (en) * | 2022-03-09 | 2024-03-21 | Voith Patent Gmbh | Application nozzle, application mechanism and process |
DE102022105510B4 (en) * | 2022-03-09 | 2024-01-04 | Voith Patent Gmbh | Application nozzle, application mechanism and process |
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US3365325A (en) * | 1964-02-13 | 1968-01-23 | Continental Can Co | Apparatus for creation of a falling curtain of liquid |
DE3316992C2 (en) * | 1983-05-10 | 1985-05-02 | Mannesmann AG, 4000 Düsseldorf | Device for stabilizing the water curtain in cooling devices for sheet metal and strips |
ES2115700T3 (en) * | 1992-07-08 | 1998-07-01 | Nordson Corp | APPARATUS AND PROCEDURES FOR THE APPLICATION OF DISCRETE COVERAGE. |
JPH06190308A (en) * | 1992-12-25 | 1994-07-12 | Shiyuto Kosoku Doro Gijutsu Center | Spraying and painting apparatus |
EP0704752B1 (en) * | 1994-09-27 | 2001-05-30 | ILFORD Imaging Switzerland GmbH | Process and apparatus for curtain-coating a moving substrate. |
DE19513531A1 (en) * | 1995-04-10 | 1996-10-17 | Du Pont Deutschland | Method and apparatus for reducing curtain casting interference |
JP3549075B2 (en) * | 1995-06-02 | 2004-08-04 | 三菱製紙株式会社 | Curtain coating apparatus and coating method |
US5690740A (en) * | 1996-01-19 | 1997-11-25 | Smith; William C. | High volume low pressure air entrapment of overspray |
JP3621204B2 (en) * | 1996-08-20 | 2005-02-16 | 三菱製紙株式会社 | Curtain coating apparatus and coating method |
JP3676182B2 (en) | 2000-04-03 | 2005-07-27 | 三菱重工業株式会社 | Coating apparatus and coating method |
CA2469482C (en) * | 2001-12-21 | 2012-01-17 | Kimberly-Clark Worldwide, Inc. | Method for the application of a viscous composition to the surface of a paper web and their products |
US6805965B2 (en) * | 2001-12-21 | 2004-10-19 | Kimberly-Clark Worldwide, Inc. | Method for the application of hydrophobic chemicals to tissue webs |
GB0205572D0 (en) | 2002-03-09 | 2002-04-24 | Chawla Brinda P S | Medicament delivery and packaging |
FI20021677A (en) * | 2002-09-20 | 2004-03-21 | Metso Paper Inc | Arrangement in a paper / cardboard web coating device |
DE60209434T2 (en) * | 2002-12-12 | 2006-10-19 | Metso Paper, Inc. | Method and apparatus for curtain coating |
JP2005161152A (en) | 2003-12-01 | 2005-06-23 | Voith Paper Patent Gmbh | Coater |
DE102005039169A1 (en) * | 2005-08-17 | 2007-03-01 | Voith Patent Gmbh | Coating moving sheet surface, e.g. to apply aqueous pigment suspension to paper sheet, involves applying heated or predried falling curtain of coating medium from nozzle above the sheet |
DE102008040419A1 (en) | 2008-07-15 | 2010-01-21 | Voith Patent Gmbh | Curtain-coating unit for coating paper, cardboard or other fiber web with fluid to pasty coating medium in the form of single or multilayered curtain, comprises a discharge nozzle, a drip pan and/or an air barrier removing unit |
DE102008040405A1 (en) | 2008-07-15 | 2010-01-21 | Voith Patent Gmbh | Curtain-coating unit for coating a moving paper, cardboard or other fiber web with fluid to pasty coating medium, comprises a curtain coating head arranged above the fiber material web for obtaining single or multi-layered curtain |
DE102016209336B4 (en) * | 2016-05-30 | 2021-08-05 | Voith Patent Gmbh | Curtain applicator |
DE102017101373B4 (en) * | 2017-01-25 | 2022-02-03 | Voith Patent Gmbh | Curtain applicator and method for applying an application medium |
-
2017
- 2017-10-18 DE DE102017124280.5A patent/DE102017124280A1/en not_active Withdrawn
-
2018
- 2018-10-02 US US16/651,593 patent/US11434607B2/en active Active
- 2018-10-02 PL PL18782395.0T patent/PL3697543T3/en unknown
- 2018-10-02 WO PCT/EP2018/076779 patent/WO2019076627A1/en unknown
- 2018-10-02 FI FIEP18782395.0T patent/FI3697543T3/en active
- 2018-10-02 CN CN201880067840.6A patent/CN111246944B/en active Active
- 2018-10-02 EP EP18782395.0A patent/EP3697543B1/en active Active
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WO2019076627A1 (en) | 2019-04-25 |
CN111246944B (en) | 2022-06-10 |
EP3697543A1 (en) | 2020-08-26 |
US20200256017A1 (en) | 2020-08-13 |
US11434607B2 (en) | 2022-09-06 |
CN111246944A (en) | 2020-06-05 |
DE102017124280A1 (en) | 2019-04-18 |
FI3697543T3 (en) | 2023-06-21 |
PL3697543T3 (en) | 2023-07-24 |
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