Method for cutting out coating plates for use in digital printing units. A method for cutting out coating plates for use in digital printing units, where the cutting of coating plates is effected by means of a digital cutting machine, the cutting machine including a computer control and further including a mother roller, the method including at least the following steps: • a file including at least cutting data is transferred to the computer control of the digital cutting machine; • a sleeve with coating plate material is mounted on the mother roller of the cutting machine; • the coating plate mounted on the sleeve and the mother roller are cut out in the ratio 1: 1 whereby is achieved, among others, that a mounting machine is no longer necessary in order to apply coating material on a sleeve, whereby registering accuracy is increased and shrinking effect is avoided.
A composite doctor blade chamber (1) for a doctor blade chamber system for rotary printing units, the doctor blade chamber (1) including a front side with an open channel (8), wherein the doctor blade chamber is made of two composite profiles, an open profile (30) with a front side and a back side and a closed profile (33) with a front side and a back side, wherein the front side (31) of the open profile is joined with the back side of the closed profile (35), whereby is achieved low weight and high strength, high corrosion resistance, a cleaning-friendly surface, less waste of ink, nice appearance and an improved working environment. In addition it is an object of the invention to provide a doctor blade chamber system with the above mentioned advantages where replacement of doctor blades can be performed faster, more easily and without use of tools.
A doctor beam for use in a printing unit, e.g. a flexographic printing unit, wherein the doctor beam has a front side with a U-shaped channel, wherein the doctor beam is made of metal and includes a surface coating produced by Plasma Electrolytic Oxidation (PEO), the surface coating at least covering the U-shaped channel, and wherein the doctor beam further includes a non-stick ceramic coating, whereby is achieved the possibility of using metal for making doctor beams without risking their degrading, neither due to chemical impact of the applied inks/lacquers/primers nor due to the destruction of the surface coating by cleaning liquids. The invention also concerns a method for treating the surface of a doctor beam and use of a doctor beam.
The present invention concerns an apparatus for conveying a sheet-formed item from a digital printing unit, the apparatus including an inlet side and an outlet side, and including a set of conveying means, e.g. one, two or more longitudinal conveyor belts, for moving items in a conveying direction. The invention also relates to a method for regulating such an apparatus. The new feature of the invention is that the apparatus includes means for aligning an article from one position to another position in relation to one or more reference points, and further includes fixing means for fixing an item at a given position in relation to a stop. The method can include at least the following method steps: detecting an item; activating conveying means for receiving and conveying an item at a second speed; regulating a possible skew position of the item as the item is moved against a stop on the conveying means, where the item is acted on by one speed of the conveyor belt and moved into abutment on the conveying means at a second and lower speed; and where the item is fixed in the obtained and aligned position.
B65H 7/08 - Controlling article feeding, separating, pile-advancing, or associated apparatus, to take account of incorrect feeding, absence of articles, or presence of faulty articles by feelers or detectors responsive to presence of faulty articles or incorrect separation or feed responsive to incorrect front register
B65H 9/06 - Movable stops or gauges, e.g. rising and falling front stops
B65H 9/10 - Pusher or like movable registers; Pusher or gripper devices which move articles into registered position
The present invention concerns an apparatus for corona treatment, the apparatus including a corona treatment unit (1) with an inlet side (2) and an outlet side (3), wherein the unit (1) includes one or more sets of transverse electrodes ( 10, 11), at least one electrode (10) in each set being connected to a high voltage source and at least one second electrode (11) connected electrically to earth, wherein the second electrode connected to earth includes a rotatable roller. The new feature according to the invention is that the apparatus is a through-flow apparatus adapted for corona treatment of material in sheets (9), and including at least one conveying table (4) with a transverse direction and a longitudinal direction, where the at least one conveying table (4) includes mechanical conveyor means. By such a solution is achieved an apparatus through which sheets (9) of material can be conveyed and corona- treated without holding the material and pulling it through the apparatus.
The present invention concerns a printing roller for a printing machine, e.g. for a flexographic printing machine, wherein the printing roller includes a rotary and longitudinal axis and an external surface, the external surface being substantially cylindrical and adapted for mounting a plate. The new feature of a printing roller according to the invention is that the external cylindrical surface includes at least one longitudinal groove, where the at least one longitudinal groove includes a geometry with one or more surfaces, the surface or surfaces lying within a circumscribed cylindrical surface for the external surface of the printing roller. In other words, this means that the longitudinal groove or grooves are cutouts in the form of milled or ground grooves in the external cylindrical surface itself on a printing roller.
A printing unit (1) comprises a first roller (2) and a second roller (3) provided substantially parallel and facing with each other for transport of printing sheets between the first roller (2) and the second roller (3). The first roller (2) is rotationally mounted at only one end (10) of the first roller (2) and wherein this one end (10) is mounted to a deflector (9). The deflector (9) comprises a connection (11) to a support (12) for resiliently changing the angle of the first roller (2) relatively to the second roller (3) by bending the connection (11).
An arrangement comprises a stacker configured to stack planar workpieces into stacks, and a cutter configured to cut preforms out of planar workpieces. The cutter is located downstream of said stacker on a manufacturing line, and a conveyor exists between said stacker and cutter. The arrangement comprises a conveyor controller, which is configured to, after transferring a stack from said conveyor to a feeder section of said cutter, rewind the conveyor to place a foremost free location after existing stacks on the conveyor to a position where it is ready to receive a stack from said stacker.
B65G 47/28 - Devices influencing the relative position or the attitude of articles during transit by conveyors arranging the articles, e.g. varying spacing between individual articles during transit by a single conveyor
B65G 47/26 - Devices influencing the relative position or the attitude of articles during transit by conveyors arranging the articles, e.g. varying spacing between individual articles
9.
ON-DEMAND OPERATION OF A FLEXOGRAPHIC COATING UNIT
A coating unit is located after a sheet-fed digital printer on a manufacturing line. As a response to a workpiece entering the coating unit from the printer, coating substance is dosed (203) onto a plate cylinder (101), and said plate cylinder (101) is rotated to transfer said coating substance onto the workpiece, which is then transferred further on the manufacturing line. As a response to a first time limit expiring after transferring said workpiece further without a subsequent work- piece entering the coating unit, the rotation of the plate cylinder (101) is stopped.
The invention concerns a system and a method for regulating the flow of a viscosity- dependent liquid in a graphic process, including a pump (5) configured for pumping a viscosity-dependent liquid (3) from a first container (4) and to a graphic printing machine (1), and wherein the viscosity of the liquid (3) affects operation of the pump (5),a sensor (8) connected with the pump (5) and which is configured to measure at least one of the operational parameters of the pump (5), and a controller (9) connected with the sensor (8) and which is configured to analyse the data from the sensor (8). The controller (9) determines the viscosity of the liquid (3) from the measured operational parameters of the pump (5) and generates a control signal (17) from the measured viscosity, based on which the viscosity of the liquid (3) pumped through the pump (5) can be adjusted.
F04C 13/00 - Adaptations of machines or pumps for special use, e.g. for extremely high pressures
G01F 3/02 - Measuring the volume flow of fluids or fluent solid material wherein the fluid passes through the meter in successive and more or less isolated quantities, the meter being driven by the flow with measuring chambers which expand or contract during measurement
G05D 24/02 - Control of viscosity characterised by the use of electric means
G01N 11/00 - Investigating flow properties of materials, e.g. viscosity or plasticity; Analysing materials by determining flow properties
11.
CLEANING ARRANGEMENT AND METHOD FOR CLEANING A FLEXOGRAPHIC COATING UNIT
The invention concerns in general the technology of automatic maintenance operations in printing and package manufacturing machinery. Especially the invention concerns the task of maintaining smooth and reliable operation of a coater that on a manufacturing line comes after a sheet-fed printer. Th invention relates to a cleaning arrangement for a coater that comprises a plate cylinder (101), the cleaning arrangement comprising: a cleaning web (202), a tangential moving mechanism (203, 204) configured to controllably move said cleaning web (202) in at least one direction in a plane defined by said cleaning web (202), a radial moving mechanism (205, 302) configured to controllably move said cleaning web (202) in at least one direction out of said plane, and a controller (501) coupled to said tangential and radial moving mechanisms (203-205, 302), said controller (501) being configured to control the moving of said cleaning web (202) in conformity with input signals received by said controller (501).
The present invention concerns a printing unit with a doctor blade chamber and a rotatable roller, wherein a gasket is provided for sealing between the doctor blade chamber and the roller, where the gasket at one side includes at least one sealing surface towards the doctor blade chamber, the gasket having a thickness which is delimited by a first edge and a second edge at the sealing surface, wherein the gasket at its other side includes an elastomeric edge for sealing abutment against the roller. The new feature of the invention is that the gasket has an elastomeric edge which is offset in longitudinal direction of the roller relative to at least one of the edges mentioned in the introduction and which delimit the thickness of the sealing surface, wherein the surface is inclining corresponding to it being angled less than 90° in relation to the sealing surface, is concave and/or is convex.
For sealing between a doctor blade chamber (3) and a rotatable roller (16, 23) in a printing unit there is provided a gasket (4) having an elastomeric edge (17, 18) for sealing abutment against the roller. The gasket includes a rigid/supporting rail (7) which during operational conditions of the printing unit bears against the roller together with the elastomeric edge or which is spaced apart from the roller.
A printing unit with a rotary roller and an ink chamber with an elastic sealing doctor blade (2) which in a curve with decreasing curvature extends from a holder (6) to a tangential point of contact on the surface of the rotary roller. A packing follows the curvature in order to seal between the sealing doctor blade and the ink chamber.
The invention concerns a method for dismounting as well as mounting a replaceable sleeve on a rotatable and radially displaceable roller (1) for a printing unit in a printing machine. The invention furthermore concerns such a printing machine with at least one printing unit, wherein the roller at the ends is provided with bearings (4, 9) arranged in two radially displaceable slides (6, 12) on the printing machine, and where the roller can be released from the printing machine at one end of the roller. The new features of the method and the printing unit according to the invention are that the roller is provided with displacing means, and by these is displaced in its longitudinal direction prior to dismounting a sleeve, whereby the roller is drawn out of engagement with the one fixed and radially displaceable slide, after which the slide and the roller may be displaced radially in relation to eacht other, and whereafter the sleeve is released and dismounted by being drawn off the roller in its longitudinal direction.
The present invention concerns a method for mounting and dismounting a doctor blade chamber (1) in a support holder (2) on a printing unit as well as an apparatus in which the doctor blade chamber is placed in the support holder in a mounting position and subsequently is brought in contact with a roller (3), preferably an anilox roller, in a position of operation. The new feature of the method and the apparatus is that the doctor blade chamber is disposed with the opening upwards in the support holder, preferably in a horizontal position or in a position at such a small angle that ink does not run out of the doctor blade chamber, and is brought into a position under the roller, after which the doctor blade chamber is brought into contact with the roller and pivoted about an axis coinciding with the rotary axis of the roller, into the position of operation.