SHEET FINISHER, IMAGE FORMING APPARATUS USING THE SAME, AND SHEET FINISHING METHOD

摘要

A sheet finisher of the invention includes a saddle stitch unit configured to stitch a center of a sheet bundle in which printed sheets are bundled, a fold unit configured to fold the center stitched by the saddle stitch unit and to form a fold line, and a fold reinforcing unit configured to reinforce the fold line formed by the fold unit, the fold reinforcing unit includes a roller unit that includes a reinforce roller with a structure for preventing an occurrence of a wrinkle, and moves along a direction of the fold line while applying pressure by the reinforce roller to the fold line of the sheet bundle transported from the fold unit, and a drive unit configured to move the roller unit along the direction of the fold line from a standby position located at a position separate from an end of the sheet bundle.