Printer having automatic paper positioning means

A device for printing a sheet-like record carrier comprising a cylindrical drum which is rotatable about its longitudinal axis and to which clamping means are secured which are rotatable about an axis extending parallel to the drum axis and which upon rotation of the drum in the printing direction of rotation hold the carrier and release the carrier upon rotation of said drum in the opposite direction, for which purpose the clamping means are in engagement with control elements and with guiding means for guiding the sheet-like record carrier on said drum, said drum having a slot dimensioned for receiving the carrier which extends into the circumference of said drum, said device including clamping means having first and second ends, said slot being dimensioned and configured for engagement with said first end of said clamping means, said device including a disk, said second end of said clamping means engaging the circumference of said disc, said disc being rotatable about the axis of said drum and with respect to said drum and which carries on its outer side a first stopper element which follows its rotation and which resiliently cooperates with a second fixed stopper element secured to a housing of the device in such a manner that upon rotation of the drum in the printing direction of rotation one of said stopper elements slips over the other, and upon rotation of said drum in the opposite direction said stopper elements preventing rotation of said disc, said device including a tensile spring which is arranged between said disk and said drum, said tensile spring being stretched when said drum is rotated in the opposite direction.