Patent ID: 7950641

Claim:
A sheet creaser comprising: a conveyer unit that receives a sheet set including at least one sheet and conveys the sheet set; a folding unit that receives the sheet set from the conveyer unit and folds the sheet set along a folding line thereby obtaining a folded sheet set having a folded side; a pressing unit that presses the folded side of the folded sheet set by sliding back and forth in a direction substantially perpendicular to a conveying direction of the sheet set; a switching unit that switches the conveyer unit between a first position to convey the sheet set and a second position unable to convey the sheet set; a driving unit that commonly drives the switching unit and the pressing unit, wherein the conveyer unit includes a first conveyer roller that rotates and a second conveyer roller that is moved close to or apart from the first conveyer roller by the switching unit, whereby the conveyer unit conveys the sheet set in such a manner the sheet set being nipped by the first conveyer roller and the second conveyer roller; and the driving unit moves the second conveyer roller close to or apart from the first conveyer roller depending on a position of the pressing unit; and a sliding mechanism that causes, by operation of a belt, the pressing unit to slide in a direction substantially parallel to a longitudinal direction of the folding unit; and a link mechanism that causes the second conveyer roller to move in a direction substantially perpendicular to the longitudinal direction of the folding unit, wherein the driving unit includes a motor as a common driving source for both the switching unit and the pressing unit: and a transmission mechanism that transmits rotation of the motor to both a slidable roller via the sliding mechanism and the second conveyer roller via the link mechanism.