The invention relates to devices for aligning sheets (1), which are
overlapped with an offset and supplied to the device by a stream feeder
and which can be transferred to a device (63) that is located downstream,
after alignment of the front edge and one lateral edge of the sheets. At
least pant of a sheet can be brought to rest on the periphery of an
alignment cylinder (62), which is used to align the front edge of the
sheet by means of front lay marks located on the periphery of said
cylinder. At least one recess is provided on the periphery of the
alignment cylinder, which, by the application of a negative pressure to
said recess allows at least part of the sheet to be fixed by friction on
the periphery of the alignment cylinder, in such a way that in the
contact zone, drive forces from said cylinder can be transferred by
friction to the sheet. A measuring device (64) determines the offset of a
lateral edge of the sheet in relation to a predetermined set alignment. A
transversal displacement device is used to align a lateral edge of the
sheet in accordance with the measurement result of the measuring device.
The acceleration and/or speed and/or angle of rotation of the drive motor
for driving the rotation of the alignment cylinder can be controlled or
adjusted according to predetermined laws of motion, in particular in
accordance with the angle of rotation of the alignment cylinder.