A folding arrangement intended for folding of a continuous flow of box blanks. The folding arrangement includes: a feeding arrangement adapted to generate the continuous flow of box blanks through the folding arrangement and a folding unit. Also is a folding machine including the arrangement. Also is a method for adjustable folding of box blanks passing through the folding arrangement.

An image processing device includes: a fold unit that folds a first adjustment sheet including an adjustment pattern, over the adjustment pattern based on a predetermined reference fold position; an image reader that reads an image of the adjustment pattern with the first adjustment sheet folded by the fold unit unfolded; a position identifying unit that, based on a fold line in the image of the adjustment pattern read by the image reader, identifies a position of the fold line; and a position adjusting unit that adjusts a fold position of the fold unit based on a difference between the position of the fold line identified by the position identifying unit and the reference fold position. The image reader includes a scanner that scans the first adjustment sheet relatively in a direction along fold of the first adjustment sheet, and reads the image of the adjustment pattern.

A folding arrangement intended for folding of a continuous flow of box blanks. The folding arrangement includes: a feeding arrangement adapted to generate the continuous flow of box blanks through the folding arrangement and a folding unit. Also is a folding machine including the arrangement. Also is a method for adjustable folding of box blanks passing through the folding arrangement.

An image processing device includes: a fold unit that folds a first adjustment sheet including an adjustment pattern, over the adjustment pattern based on a predetermined reference fold position; an image reader that reads an image of the adjustment pattern with the first adjustment sheet folded by the fold unit unfolded; a position identifying unit that, based on a fold line in the image of the adjustment pattern read by the image reader, identifies a position of the fold line; and a position adjusting unit that adjusts a fold position of the fold unit based on a difference between the position of the fold line identified by the position identifying unit and the reference fold position. The image reader includes a scanner that scans the first adjustment sheet relatively in a direction along fold of the first adjustment sheet, and reads the image of the adjustment pattern.

A folding processing unit in a sheet post-processing device comprises a first conveying path, upstream side conveying rollers, downstream side conveying rollers, folding rollers between the upstream side conveying rollers and the downstream side conveying rollers, and the second folding rollers. The folding rollers fold a sheet at the first nip portion between the two rollers. The second folding rollers are placed at a downstream side of the first nip portion. An edge face detection sensor for detecting the edge face of the sheet is placed on the first conveying path, at a downstream side of the first nip portion. The second folding rollers pinch the sheet folded by the first nip portion at the second nip portion, to further fold the sheet, based on the detection result of the edge face detection sensor. Herewith, degree of accuracy for folding behavior improves.