Patent ID: 9061847
Filing Date: 2015-06-23
Classification: B65H

Abstract:
1. A sheet transport mechanism comprising: transport roller pairs constituted by drive roller rotated by drive power from a drive source, and driven roller pressed into contact against the drive roller and passively driven thereby; and roller pressing mechanism for pressing the driven roller into contact against the drive roller; the sheet transport mechanism being adapted to transport a recording medium pinched in a nip section of the transport roller pairs, wherein the driven roller includes a central driven roller disposed to a center side in the axial direction, with a first rotating shaft for supporting the central driven roller, at least one pair of outside driven rollers arranged symmetrically on either side of the central driven roller in an axial direction, and with second rotating shafts for supporting the outside driven rollers; the roller pressing mechanism includes a central pressing mechanism for pressing the central driven roller into contact against the drive roller, and an outside pressing mechanism for pressing the outside driven rollers into contact against the drive roller; the central pressing mechanism has a pair of central pressing members for pressing on both ends of the first rotating shaft towards the drive roller side, and a central urging member linked to the pair of central pressing members, and adapted for urging the central pressing members to impart pressing force; the outside pressing mechanism has a pair of outside pressing members for pressing the pair of second rotating shafts towards the drive roller side, and an outside urging member linked to the pair of outside pressing members, and adapted for urging the outside pressing members to impart pressing force; and the pressing force of the central pressing members exceeds the pressing force of outside pressing members.