Abstract: The bookbinding device of the present invention includes: a pair of holders capable of changing postures between a first posture of holding and restraining a lateral portion of a sheet bundle covered with a cover sheet, and a second posture of releasing the restraint; a tabular heating plate capable of generating heat for melting the hot-melt adhesive; a tabular cooling plate; a movable support plate which is arranged movably below the holders and supports the heating plate and the cooling plate; a first drive unit for changing the posture of the holders to the first posture or the second posture; a second drive unit for moving the movable support plate between a first position where the heating plate is positioned at a lower side of a holding space where the holders hold the sheet bundle, and a second position where the cooling plate is positioned at a lower side of the holding space; and a controller for controlling the operation of the first drive unit and the second drive unit.

Abstract: Provided is a bookbinding device having a thickness measuring unit including a movable piece that moves according to the thickness of a sheet bundle to be bound, a bookbinding processing unit for performing bookbinding processing in a state of being positioned at a prescribed processing position, and a synchronization mechanism for changing the processing position of the bookbinding processing unit in synchronization with the movement of the movable piece.