Characterization, determination of a characteristic number and selection of suitable dressings on cylinders of a printing press
OwnerKarl Schaschek, Ralf Christel +3inventors
InventorsKarl Schaschek, Ralf Christel, Oliver Hahn, Bernd Masuch, Kurt Weschenfelder
Life of this patent
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Abstract
In connection with a method for characterization of a layer, a method and a device for determining a characteristic number, as well as a method for selecting a suitable dressing on rollers, or suitable geomtries of rollers of a printing press, a characterizing number for characterizing a layer is formed, or employed, which characterizes the roll-off behavior independently of a measuring device or an application in a particular printing group.
Claims72
A print unit comprising:
- at least first and second cooperating rollers;
- an elastic layer on a surface of one of said first and second rollers;
- an undeformable surface on the other one of said first and second rollers;
- a characterizing a number between 0.980 and 1.000 which describes elastic properties of an area of relative compression of said elastic layer, said characterizing number being formed by an algebraic specification
- α
- =
- I
- real
- -
- I
- inkomp
- I
- komp
- -
- I
- inkomp
- wherein Ikomp, Iinkomp represent numbers of revolutions ratios for extreme cases of a purely compressible and of a purely incompressible elastic layer Ireal and represents a desired number of revolutions ratio.
A print unit comprising:
- at least first and second cooperating rollers;
- at least one of said first and second cooperating rollers having an elastic layer on its surface, the other of said at least first and second rollers having an undeformable surface, said layer and geometries of said first and second rollers being alternatingly matched to each other wherein in case of a variation in at least a section of a relative compression of said elastic layer, a number of revolutions ratio Ireal deviates from 1.000/n in a range of no greater than 0.002 wherein n represents a ratio between a number of printed pages in a circumferential direction of said roller with said layer to a number of printed pages on said roller with said undeformable surface.
A print unit comprising:
- at least first and second cooperating rollers;
- an elastic layer on a surface of one of said first and second rollers;
- and
- a largely undeformable surface on the other of said first and second rollers, wherein geometries of said first and second rollers are alternatingly matched to each other such that in at least an area of contact with a relative compression of said elastic layer a differential quotient (dIreal/dS) between a number of revolutions ratio (Ireal) and said relative compression deviates at no more than 0.01 from zero.
A device for determining a roll-off behavior of an elastic layer comprising:
- a first roller supporting the elastic layer;
- a second roller having a substantially undeformable surface;
- a frame supporting said first and second rollers;
- an eccentric bushing in said frame, said eccentric bushing supporting at least one of said first and second rollers wherein an axial distance between said first and second rollers can be changed;
- and
- means for determining a number of revolutions ratio (Ireal) between said first and second rollers.
A device for determining a roll-off behavior of an elastic layer comprising:
- a first roller supporting the elastic layer;
- a second roller having a substantially undeformable surface;
- means supporting said first and second rollers for changing an axial spacing distance between said first and second rollers;
- a lever supported by one of said first and second rollers, said lever transmitting said change in said axial spacing distance;
- a path-measuring device in contact with said lever and detecting said change in said axial spacing distance;
- and
- means for determining a number of revolutions ratio (Ireal) between said first and second rollers.
A method for dimensioning a roller of a print unit including:
- providing a roll-off behavior measuring device;
- using said roll-off behavior measuring device and determining a roll-off behavior of an elastic layer usable in the print unit;
- providing a first roller in the print unit having a first predetermined diameter;
- and
- determining a suitable diameter of a second roller using said roll-off behavior of said elastic layer.
Dependencies are inferred from the claim text.