Sheet conveyance device, image reader, and image forming apparatus capable of feeding sheets effectively

An image reader, comprising:

• a sheet conveyance device, comprising:
• a plurality of driving rollers including a hard material;
• a driving shaft to support the plurality of driving rollers at centers of axes of the plurality of driving rollers;
• a plurality of driven rollers to oppose the plurality of driving rollers to form nip portions between the plurality of driven rollers and the plurality of driving rollers;
• and
• a driven shaft provided above the driving shaft to support the plurality of driven rollers at centers of axes of the plurality of driven rollers,
• the plurality of driving rollers and the plurality of driven rollers rotating and nipping a sheet at the nip portions to feed the sheet,
• the driving shaft rotatably supported in such a manner that a center portion of the driving shaft in an axial direction of the driving shaft is bent downstream in a sheet conveyance direction,
• the plurality of driving rollers being shifted downstream in the sheet conveyance direction and tilted with respect to the sheet conveyance direction in a V-like shape about a center line in a width direction of the sheet,
• the plurality of driven rollers, comprising:
• at least one center driven roller provided on a center portion of the driven shaft in an axial direction of the driven shaft, and including a soft material;
• and
• at least one side driven roller provided on each side portion of the driven shaft in the axial direction of the driven shaft, and including a hard material,
• the plurality of driven rollers being shifted downstream in the sheet conveyance direction by an amount determined by an amount by which the plurality of driving rollers is shifted downstream in the sheet conveyance direction.

An image forming apparatus, comprising:

• a sheet conveyance device, comprising:
• a plurality of driving rollers including a hard material;
• a driving shaft to support the plurality of driving rollers at centers of axes of the plurality of driving rollers;
• a plurality of driven rollers to oppose the plurality of driving rollers to form nip portions between the plurality of driven rollers and the plurality of driving rollers;
• and
• a driven shaft provided above the driving shaft to support the plurality of driven rollers at centers of axes of the plurality of driven rollers,
• the plurality of driving rollers and the plurality of driven rollers rotating and nipping a sheet at the nip portions to feed the sheet,
• the driving shaft rotatably supported in such a manner that a center portion of the driving shaft in an axial direction of the driving shaft is bent downstream in a sheet conveyance direction,
• the plurality of driving rollers being shifted downstream in the sheet conveyance direction and tilted with respect to the sheet conveyance direction in a V-like shape about a center line in a width direction of the sheet,
• the plurality of driven rollers comprising:
• at least one center driven roller provided on a center portion of the driven shaft in an axial direction of the driven shaft, and including a soft material;
• and
• at least one side driven roller provided on each side portion of the driven shaft in the axial direction of the driven shaft, and including a hard material,
• the plurality of driven rollers being shifted downstream in the sheet conveyance direction by an amount determined by an amount by which the plurality of driving rollers is shifted downstream in the sheet conveyance direction.