A scanner includes a reading unit that reads an image of a paper, a medium feeding portion that is capable of selecting a first feeding mode in which a separation feeding for separately feeding a paper bundle in which a plurality of sheets of paper is overlapped with each other is performed and a second feeding mode in which a non-separation feeding for collectively feeding the paper bundle without separating is performed, and a pair of first transporting rollers and a pair of second transporting rollers that transport the paper fed by the medium feeding portion, in a case in which the medium feeding portion feeds the paper in the second feeding mode, a first driven roller and a second driven roller respectively constituting the pair of first transporting rollers and the pair of second transporting rollers are driven in a rotation direction where the paper is transported.

A scanner includes a reading unit that reads an image of a paper, a medium feeding portion that is capable of selecting a first feeding mode in which a separation feeding for separately feeding a paper bundle in which a plurality of sheets of paper is overlapped with each other is performed and a second feeding mode in which a non-separation feeding for collectively feeding the paper bundle without separating is performed, and a pair of first transporting rollers and a pair of second transporting rollers that transport the paper fed by the medium feeding portion, in a case in which the medium feeding portion feeds the paper in the second feeding mode, a first driven roller and a second driven roller respectively constituting the pair of first transporting rollers and the pair of second transporting rollers are driven in a rotation direction where the paper is transported.

A sheet processing device includes a rotator, a first nipper, a conveyor, a second nipper, a detector, a memory, and circuitry. The rotator winds a two-ply sheet around the rotator to generate a winding circumferential difference between two sheets of the two-ply sheet to separate the two sheets. The detector detects an abnormal condition, in which a gap greater than a given interval is not formed between the two sheets around the rotator. The memory stores a detection result as the abnormal condition. The circuitry is to increase a nipping force of the second nipper with the rotator, and increase the nipping force in a present sheet processing to be greater than a previous nipping force of the second nipper in a previous sheet processing, when the memory stores the detection of the abnormal condition in the previous sheet processing, to wind the two sheets around the rotator.

A sheet processing device includes a rotator, a first nipper, a conveyor, a second nipper, a detector, a memory, and circuitry. The rotator winds a two-ply sheet around the rotator to generate a winding circumferential difference between two sheets of the two-ply sheet to separate the two sheets. The detector detects an abnormal condition, in which a gap greater than a given interval is not formed between the two sheets around the rotator. The memory stores a detection result as the abnormal condition. The circuitry is to increase a nipping force of the second nipper with the rotator, and increase the nipping force in a present sheet processing to be greater than a previous nipping force of the second nipper in a previous sheet processing, when the memory stores the detection of the abnormal condition in the previous sheet processing, to wind the two sheets around the rotator.

A scanner includes a reading unit that reads an image of a paper, a medium feeding portion that is capable of selecting a first feeding mode in which a separation feeding for separately feeding a paper bundle in which a plurality of sheets of paper is overlapped with each other is performed and a second feeding mode in which a non-separation feeding for collectively feeding the paper bundle without separating is performed, and a pair of first transporting rollers and a pair of second transporting rollers that transport the paper fed by the medium feeding portion, in a case in which the medium feeding portion feeds the paper in the second feeding mode, a first driven roller and a second driven roller respectively constituting the pair of first transporting rollers and the pair of second transporting rollers are driven in a rotation direction where the paper is transported.