Printing drum of rotary stencil printer having a predetermined allowance for bulging out

摘要

A printing drum for a rotary stencil printer having a sidewall in the form of a flexible perforated sheet. In order to allow for a bulging out deformation of the sidewall by an internal press roller to be easier and more uniform over the entire width of the printing, the flexible cylindrical body of the printing drum has its opposite side edge portions seated around the outer circumferential surfaces of a pair of annular portions (10a, 10b). The drum is constructed to have an inner circumferential length greater than the circumferential length of the outer circumferential surface of the annular portions by a predetermined amount which allows for a predetermined bulging out deformation of the flexible cylindrical body.