SHEET FINISHER, IMAGE FORMING APPARATUS AND SHEET FINISHING METHOD

摘要

A sheet finisher according to an embodiment includes: a fold roller which folds a central area of a sheet bundle to form a fold line on the sheet bundle; a fold reinforcing roller which moves along a direction of the fold line while pressing the fold line of the sheet bundle to reinforce the fold line; and a drive unit which includes a motor and transmits a drive torque of the motor to the fold reinforcing roller, so that the drive torque can be changed, to move the fold reinforcing roller along the fold line.