US 11,752,756 B2
Method of operating a flexographic printing press, and system
Werner Schwab, Bechtsrieth (DE)
Assigned to Heidelberger Druckmaschinen AG, Heidelberg (DE)
Filed by Heidelberger Druckmaschinen AG, Heidelberg (DE)
Filed on Oct. 22, 2021, as Appl. No. 17/507,888.
Claims priority of application No. 102020213324.7 (DE), filed on Oct. 22, 2020.
Prior Publication US 2022/0126561 A1, Apr. 28, 2022
Int. Cl. B41F 5/24 (2006.01); B41F 13/14 (2006.01); B41F 13/24 (2006.01); B41F 33/00 (2006.01)
CPC B41F 5/24 (2013.01) [B41F 13/14 (2013.01); B41F 13/24 (2013.01); B41F 33/0081 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A method of operating a flexographic printing press, the method comprising:
providing the flexographic printing press including a printing cylinder carrying a sleeve with at least one flexographic printing forme or a flexographic printing cylinder and an impression cylinder;
using a motor of the flexographic printing press for adjusting a contact pressure between the printing cylinder or the flexographic printing cylinder and the impression cylinder;
measuring a dot density of the flexographic printing forme in a contact-free manner in a measuring operation in a measuring device before a printing operation;
using a camera and a reference object in the measuring operation;
the reference object extending in a direction parallel to an axis of a cylinder of the measuring device carrying the sleeve during the measuring operation, the reference object creating a reference line for computationally calculating the dot density;
carrying out the adjustment in an automated manner as a function of the dot density of the flexographic printing forme, the dot density being a location-dependent density of printing elevations of the flexographic printing forme, or data computationally derived from the location-dependent density; and
carrying out the printing operation with the adjusted contact pressure.