Abstract: A curtain application unit for applying a liquid or pasty application medium to at least one surface of a moving material web, in particular a fibrous web, includes an application head having at least one separation edge extending substantially over the width of the application head. The application medium exits the application head in the form of a free-falling curtain at the separation edge. At least one rinsing device is used to apply a flowing gaseous rinsing medium to the at least one separation edge, and at least one blocking device is suitable for keeping air movements of the ambient air away from the curtain. A method for coating a moving material web is also provided.

Abstract: A curtain application unit for applying a liquid or pasty application medium to at least one surface of a moving material web, in particular a fibrous web, includes an application head having at least one separation edge extending substantially over the width of the application head. The application medium exits the application head in the form of a free-falling curtain at the separation edge. At least one rinsing device is used to apply a flowing gaseous rinsing medium to the at least one separation edge, and at least one blocking device is suitable for keeping air movements of the ambient air away from the curtain. A method for coating a moving material web is also provided.

Abstract: The present invention provides a doctor device for metering and/or equalizing a liquid-to-pasty medium applied to a running surface, wherein in the case of direct application the surface is a running paper web, paperboard web or other fibrous web and in the case of indirect application a transfer element which transfers the application medium to the fibrous web. The doctor device has a holder arranged on a support beam for accommodating a doctor element used for the metering and/or equalizing. The holder has a first fixed support face bar and a second moving support face bar, wherein to open and close the holder the second support face bar is displaceable respectively away from the first support face bar or toward it such that in the closed state of the holder the doctor element is fixed from the outside and in the open state of the holder it is released.

Abstract: A method for operating a machine for single or double sided application of a liquid or viscous coating medium by way of at least one applicator unit onto the surface of a mating material web, especially a paper or cardboard web is provided. The coating medium collecting unit is cleaned prior to, during or after an application process of the machine, by way of supplying cleaning liquid via the supply line. The valve arrangement can be switched to the second valve condition for clean-up and to the third valve condition for the collection of coating medium in the medium collecting device. The medium collecting unit can be cleaned after start of the application process, during coating, through elements of supplying cleaning liquid via the supply line.

Abstract: A machine for single or double sided application of a liquid or viscous coating medium by way of at least one applicator unit onto the surface of a mating material web, especially a paper or cardboard web. A medium collecting device that is allocated to the applicator unit or to a dispensing component of the applicator unit which includes the dispensing openings, is equipped with a receiving and release component which is allocated to the medium collecting device and which is or can be mounted detachably on same. During the start of the application process the component releases the curtain or veil due to a common adjustment with the medium collecting device or of a section component of same relative to the curtain or veil from a rim extending across the moving background or from an edge extending across the moving background.

Abstract: A method for operating a machine for single or double sided application of a liquid or viscous coating medium by way of at least one applicator unit onto the surface of a mating material web, especially a paper or cardboard web is provided. The coating medium collecting unit is cleaned prior to, during or after an application process of the machine, by way of supplying cleaning liquid via the supply line. The valve arrangement can be switched to the second valve condition for clean-up and to the third valve condition for the collection of coating medium in the medium collecting device. The medium collecting unit can be cleaned after start of the application process, during coating, through elements of supplying cleaning liquid via the supply line.

Abstract: A device for direct or indirect application of liquid or viscous coating medium by way of an application system onto a material web, especially a paper or cardboard web, including a weakening device for weakening the boundary layer of air that is carried along by the application surface. The weakening device is located prior to the applicator device viewed in direction of travel of the application surface. The weakening device includes a blowing device and a suction device. The blowing device is located prior to the applicator device when viewed in direction of travel of the application surface and produces an air flow in opposite direction to the direction of travel. The suction device is located prior to the blowing device when viewed in direction of travel of the application surface and sucks off at least a portion of the air flow that is produced by the blowing device, as well as at least a portion of the boundary layer of air that is carried along by the application surface.

Abstract: The invention relates to a method for applying a multiple layer directly to a paper, board or other moving web of fibrous material during the production and/or finishing thereof, the individual layers of the multiple layer being formed of a plurality of liquid to pasty application media or liquid streams (Q1-Qn), in particular aqueous pigment suspensions. The individual application media or liquid streams (Q1-Qn) are discharged onto the fibrous web without respective previous drying, without excess quantities, without mixing with one another, and without contact.

Abstract: The present invention provides a doctor device for metering and/or equalizing a liquid-to-pasty medium applied to a running surface, wherein in the case of direct application the surface is a running paper web, paperboard web or other fibrous web and in the case of indirect application a transfer element which transfers the application medium to the fibrous web. The doctor device has a holder arranged on a support beam for accommodating a doctor element used for the metering and/or equalizing. The holder has a first fixed support face bar and a second moving support face bar, wherein to open and close the holder the second support face bar is displaceable respectively away from the first support face bar or toward it such that in the closed state of the holder the doctor element is fixed from the outside and in the open state of the holder it is released.

Abstract: A device for direct or indirect application of liquid or viscous coating medium by way of an application system onto a material web, especially a paper or cardboard web, including a weakening device for weakening the boundary layer of air that is carried along by the application surface. The weakening device is located prior to the applicator device viewed in direction of travel of the application surface. The weakening device includes a blowing device and a suction device. The blowing device is located prior to the applicator device when viewed in direction of travel of the application surface and produces an air flow in opposite direction to the direction of travel. The suction device is located prior to the blowing device when viewed in direction of travel of the application surface and sucks off at least a portion of the air flow that is produced by the blowing device, as well as at least a portion of the boundary layer of air that is carried along by the application surface.

Abstract: A device for direct or indirect application of liquid or viscous coating medium by way of an application system onto a material web, especially a paper or cardboard web, including a weakening device for weakening the boundary layer of air that is carried along by the application surface. The weakening device is located prior to the applicator device viewed in direction of travel of the application surface. The weakening device includes a blowing device and a suction device. The blowing device is located prior to the applicator device when viewed in direction of travel of the application surface and produces an air flow in opposite direction to the direction of travel. The suction device is located prior to the blowing device when viewed in direction of travel of the application surface and sucks off at least a portion of the air flow that is produced by the blowing device, as well as at least a portion of the boundary layer of air that is carried along by the application surface.

Abstract: A machine for single or double sided application of a liquid or viscous coating medium by way of at least one applicator unit onto the surface of a mating material web, especially a paper or cardboard web. A medium collecting device that is allocated to the applicator unit or to a dispensing component of the applicator unit which includes the dispensing openings, is equipped with a receiving and release component which is allocated to the medium collecting device and which is or can be mounted detachably on same. During the start of the application process the component releases the curtain or veil due to a common adjustment with the medium collecting device or of a section component of same relative to the curtain or veil from a rim extending across the moving background or from an edge extending across the moving background.

Abstract: An apparatus for applying liquid or pasty application medium, in particular aqueous pigment suspension, to one or both sides of a moving material web, especially to a paper or board web, during its production and/or finishing. The invention provides for the vacuum generating device to be assigned to that side of the material web which faces away from the application medium curtain, at least to the region of incidence of the application medium on the material web.

Abstract: An apparatus is configured for applying at least one first layer of a first application medium and at least one second layer of a second application medium to a material web, either directly or indirectly. The at least one first layer and the at least one second layer each are first applied onto a moving base (either the web surface in the case of direct application or a transfer element in the case of indirect application). The apparatus includes a first curtain applicator unit having a first discharge nozzle and configured for discharging the first application medium through the first discharge nozzle in a form of a first curtain onto the moving base. The apparatus also incorporates a second curtain applicator unit which includes a second discharge nozzle and which is configured for discharging the second application medium through the second discharge nozzle in a form of a second curtain onto the moving base.

Abstract: A device for direct or indirect application of liquid or viscous coating medium by way of an application system onto a material web, especially a paper or cardboard web, including a weakening device for weakening the boundary layer of air that is carried along by the application surface. The weakening device is located prior to the applicator device viewed in direction of travel of the application surface. The weakening device includes a blowing device and a suction device. The blowing device is located prior to the applicator device when viewed in direction of travel of the application surface and produces an air flow in opposite direction to the direction of travel. The suction device is located prior to the blowing device when viewed in direction of travel of the application surface and sucks off at least a portion of the air flow that is produced by the blowing device, as well as at least a portion of the boundary layer of air that is carried along by the application surface.

Abstract: A device (510) for the direct or indirect application of liquid or pasty application medium (516) by means of an applicator unit (512) to a material web (520), in particular of paper or board, comprises a device (570) upstream of the applicator unit (512) in the running direction (L) of the substrate (U) in order to attenuate the air boundary layer (G) carried along by the substrate (U). The attenuation device can in this case comprise a sealing element (570) which is pressed in a sealing manner against the substrate (U) and rolls on the latter substantially without slippage, and/or can comprise an electrode arrangement and/or can comprise an ultrasound source and/or can comprise a resilient diaphragm element acting without contact.

Abstract: An apparatus for applying liquid or pasty application medium, in particular aqueous pigment suspension, to one or both sides of a moving material web, especially to a paper or board web, during its production and/or finishing. The invention provides for the vacuum generating device to be assigned to that side of the material web which faces away from the application medium curtain, at least to the region of incidence of the application medium on the material web.

Abstract: A device (10) for the direct or indirect application of liquid or pasty application medium (16) to one or both sides of a material web (20), in particular of paper or board, comprises an applicator unit (12) which discharges the application medium (16) onto the material web (20) in the form of a free application medium jet (18). In this case, in the region of the applicator unit (12) there is provided a device (30) for producing an electric field, which exerts on the application medium jet (18) moving from the applicator unit (12) to the material web (20) a force which assists its movement. Additionally or alternatively, edge guiding elements can be provided, which guide the lateral edges of the application medium curtain (18) at least on part of its movement under the force of gravity.

Abstract: A coating machine serves to directly or indirectly apply a liquid or viscous coating medium onto a moving surface. A coater imbedded in a coater bed, defines in part the metering slot. A limiting surface at the moving surface inlet of the coater bed forms, together with the moving surface, an accumulator chamber, with the opening facing in the opposite direction with respect to the feed direction. The accumulator chamber gradually reduces its volume, and the coating medium, delivered to the accumulator chamber by the moving surface, accumulates in the area ahead of the metering slot. It further includes pneumatic pressure device to alter the relative position of the limiting surface with respect to the moving surface and thus alter the geometry of the accumulator chamber.

Abstract: An application apparatus is for applying a liquid or pasty medium to a moving base. The moving base is a surface of a material web in a case of direct application and a surface of a transfer element for transferring the medium to the material web in a case of indirect application, the material web being one of paper and cardboard. The application apparatus has an inlet side and an outlet side with respect to a direction of movement of the moving base. The application apparatus includes a carrying beam; an essentially rigid supporting unit provided on the carrying beam; a sealing doctor device positioned at the inlet side of the application apparatus, the sealing doctor device being fixedly attached to the supporting unit; and a metering doctor device positioned at the outlet side of the application apparatus, the metering doctor device being fixedly attached to the supporting unit. The sealing doctor device and the metering doctor device define an application chamber therebetween.