Patent ID: 8331847

Claim:
A bookbinding system including an image forming apparatus to form an image on a sheet and a bookbinding device to bind together a batch of sheets transported from the image forming apparatus, the bookbinding system comprising: a punch unit to form a predetermined number of ring holes in a predetermined portion along a side of the sheets one by one or in a batch; a ring-binding unit disposed downstream from the punch unit in a direction in which the sheet is transported to insert rings of a ring member into the ring holes formed on the batch of sheets by the punch unit, the ring member having a ring pitch equal to an interval between the rings, and the sheets having a hole pitch equal to an interval between the ring holes; a ring detector disposed at a portion where the ring member is set to detect a type of the ring member set in the bookbinding device; and a determination unit to determine whether or not a ring-binding operation is executable based on the type of the ring member and a size of the sheets to be bound together, wherein the size of the sheets is a length of the side of the sheets to be bound by the ring-binding unit, wherein the determination unit determines that the ring-binding operation is not executable, only if a length of the ring member is greater than the length of the side of the sheets to be bound, or the ring pitch equals the hole pitch and a number of the rings is greater than the number of ring holes.