Abstract: A device 100 for the feeding of sheets 14 from a ream 18, with a main rotating, feeding roller 27; a tray 13 containing the ream 18; and an auxiliary roller 130 arranged adjacent to the feeding roller 27, wherein the tray 13 is suitable for moving cyclically to bring the ream 18 into contact with the feeding roller 27, so that the latter picks one at a time the sheets 14 from the ream 18 and feeds them along a path 131; and wherein the auxiliary roller 130 is adapted for rotating in contact with the sheets 14 picked by the feeding roller 27, but without pulling them and in the direction opposite their feeding direction, the object being that of opposing the picking of double sheets from the ream 18.

Abstract: The printer (10) has an ink jet printhead (12) suitable for printing single sheets (14) and a control device (40) adapted to delay expulsion of the same to a collection tray (16), with the purpose of extending the drying time of the ink ejected by the printhead (12) on each sheet, before a following sheet is stacked thereon. The device (40) is suitable for controlling means (17, 25) for feeding of the sheets (14) through the printer (10) so as to temporarily stop the feeding of a first sheet (14a) after it has been printed on, then to feed a second sheet (14b) until it comes to a predetermined minimum distance (D) from the first sheet (14a), and finally to simultaneously feed the first sheet (14a) and the second sheet (14b), so as to expel the first sheet (14a) to the collection tray (16) and to further feed the second sheet (14b) so that it can be printed on.