Combined sheet-fed rotary printing machine for securities, especially banknotes

A combined sheet-fed rotary printing machine having an indirect printing unit (A) which includes a first cylinder (5) comprising a first blanket cylinder, a plurality of plate cylinders (7, 10), a second cylinder (3) of substantially the same size as the first cylinder, a sheet transport device (B) for use in association with the printing unit (A), said sheet transport device comprising a plurality of transport drums, drying means (21) positioned along the sheet transport device, and an intaglio printing unit (C) for use in association with the sheet transport device, wherein said second cylinder (3) interacts with a carry-over drum (2) for feeding sheets, a transfer drum (18) for receiving sheets comprising a first transport drum of the sheet transport device, said second cylinder having a circumferential region located between the carry over drum and the transfer drum and against which a sheet rests, facing the first blanket cylinder (5), a multicolor image originating from the plate cylinders (7, 10) is transferred onto a side of a sheet facing said first blanket cylinder, said second cylinder (3) comprising a second blanket said circumferential region is at most equal to half the said second blanket cylinder's circumference, and along another circumferential region of said second blanket cylinder (3) which is not covered by a sheet are a plurality of second plate cylinders (12, 15) adjacent said second blanket cylinder such that a multicolor image originating from said second plate cylinders (12, 15) is transferred onto an opposite side of the sheet and said transfer drum (18), carry-over drum (2) and said first and second plate cylinders (7, 10, 12, 15) are of substantially the same size.