| 摘要 |
PROBLEM TO BE SOLVED: To efficiently fold a sheet bundle according to the number of sheets, the size and the sheet type without making fold wrinkles or bending, when folding the sheet bundle.SOLUTION: A sheet processing device includes: a pair of folding rollers 62, 63 arranged in pressure contact with each other to fold a sheet bundle ST passing a nip part 66 formed by the pressure contact; a thin plate-like folding knife 70 moving toward the nip part 66 of the pair of folding rollers 62, 63 while they are driven and rotated, and pushing the sheet bundle ST into the nip part 66; and a control part 100 controlling the rotation drive of the pair of folding rollers 62, 63 and the movement of the folding knife 70. The control part 100 reduces the moving speed of the folding knife 70 relative to a peripheral speed of the pair of folding rollers 62, 63 according to the number of sheet bundles ST, the sheet type, and the size (the length in a conveyance direction of the sheets, and the width which is the length in the direction perpendicular to the conveyance direction). |
