摘要 |
PROBLEM TO BE SOLVED: To convey a sheet bundle stably while corresponding to a wide range of conditions such as presence or absence of saddle stitch bookbinding, paper types, the number of sheets, temperature, humidity and the like, when the sheet bundle is subjected to center folding processing.SOLUTION: A sheet processing device includes: a folding roller pair for pressing and folding a sheet bundle constituted of a plurality of sheets, by means of nip; and a folding plate for pushing the sheet bundle into a side of a nip. When the sheet bundle is pushed into a side of the nip by the folding plate, an insertion amount is determined based on predetermined conditions such as the number of sheets to be folded, a type of paper, and environmental information including a temperature and a humidity, wherein, a sheet bundle that has been subjected to saddle stitching in such a manner that the sheet bundle is stitched at the center part thereof in a conveying direction, is processed with a larger insertion amount than that in performing center folding without stitching. |