Finishing apparatus, sheet processing method, image forming method and image forming apparatus

摘要

The invention concerns an image-forming apparatus, which conduct folding processing that is suitable for a process to form an image on a sheet. The image forming apparatus includes: a first folding device and a second folding device, both of which conduct folding processing while conveying a sheet; a controller to control both of the first folding device and the second folding device; and a selector that makes it possible to select a two-folding mode or a three-folding mode; wherein the controller controls the first folding device so as to eject the sheet after folding the sheet double when the two-folding mode is selected by the selector, while the controller controls the first folding device so as to fold the sheet double, and then, further controls the second folding device so as to eject the sheet after further folding the sheet in three when the selector selects the three-folding mode.