Patent ID: 7871065
Filing Date: 2011-01-18
Classification: B65H,G03G

Abstract:
1. A sheet folding device comprising: a guide device for holding a sheet bunch at a predetermined fold position; a folding roll device having a first folding roll and a second folding roll arranged at the fold position in pressure contact with each other; a folding blade inserting the sheet bunch supported on the guide device to a nip position between the first and second folding rolls; a roll driving device for rotationally driving the first and second folding rolls; a blade driving device for moving the folding blade from a standby position to the nip position on the folding rolls; a clutch device for releasably coupling the first and second folding rolls and the roll driving device; and a driving control device for controlling the roll driving device and the blade driving device, the driving control device controlling the clutch device so that when the folding blade inserts the sheet bunch to the nip position on the first and second folding rolls, the first and second folding rolls rotate following the inserted sheets, wherein at least one of the first and second folding rolls has a shift device for reducing or releasing a pressure contact force of the folding rolls, the shift device is configured to adjust the pressure contact force of the first and second folding rolls in conjunction with the folding blade moving from the standby position to the nip position, and the shift device and the folding blade are interconnected so that when the folding blade inserts the sheets between nips of the first and second folding rolls, the sheets are brought into pressure contact with the folding rolls by a predetermined pressure contact force to form a fold line, and when carrying out the sheets with the fold line formed thereon from the paired folding rolls, the pressure contact force is reduced to carry out the sheets downstream.