Richard J Ewalt

US Patent:

54229588, Jun 6, 1995

Filed:

Dec 30, 1993

Appl. No.:

8/176040

Inventors:

Gerald Wouch - Lisle IL
Gary Procknow - Chicago IL
Gerald J. Bender - Park Forest IL
Richard R. Ewalt - Chicago IL

Assignee:

R. R. Donnelley & Sons Company - Chicago IL

International Classification:

B41C 100

US Classification:

382141

Abstract:

A system for calibrating engraving heads used for engraving gravure printing cylinders determines a mean cell volume for cells forme din a test cut in a printing cylinder. The system of the present invention includes a procedure of cutting two or more test cuts in each printing cylinder. One of the test cuts is at the light end of the cylinder and the second is at he dark end. The morphological characteristics of a plurality of cells in each of the test cuts is measured, and morphological parameter values of the cell sin the test cut are computed. These morphological parameter values are compared with predetermined morphological parameter values, and each engraving head is adjusted in accordance with this comparison to cut the desired values within an acceptable tolerance band. The desired average values can be adjusted to take into account new inks, papers, batch variation in inks and papers, and diamond wear in the engraving head.