Abstract: There is provided a press brake that can improve forming accuracy in partial bending. A press brake includes: a conveying mechanism that intermittently conveys a workpiece; a die including a pair of shoulder portions and a groove portion located between the pair of shoulder portions, the pair of shoulder portions being arranged away from each other in a conveying direction of the workpiece and supporting a rear surface of the workpiece; a backup plate that extends on the pair of shoulder portions, covers the groove portion, and is interposed between the die and the workpiece; and a punch that moves relative to the die so as to approach the die each time the conveying mechanism stops conveying the workpiece and presses the workpiece so as to bend the workpiece within an elastic deformation region of the backup plate.

Abstract: There is provided a press brake that improves bending accuracy of a partial bending method. The press brake includes: a conveying mechanism that intermittently conveys a workpiece; a die; a punch; a crowning mechanism; a bending amount measuring device; and a control device. The control device presses an end portion of the workpiece in a conveying direction by the punch and conveys the workpiece by the conveying mechanism until the pressed portion enters into a measurement range of the bending amount measuring device. The control device drives the crowning mechanism so as to correct a crowning amount in accordance with a difference between a middle bending amount and an end bending amount measured by the bending amount measuring device.

Abstract: There is provided a press brake (1) that, if subjecting a workpiece (90) having non-uniform thickness to bending, can efficiently give uniform curvature to the workpiece (90). The press brake (1) includes: a die (2) supporting the workpiece (90); a punch supporting member (4) arranged so as to be opposed to the die (2); a moving mechanism (5) that moves the punch supporting member (4) relative to the die (2); a punch (3) that is supported by the punch supporting member (4), is opposed to the die (2) or the workpiece (90) in a relative movement direction of the punch supporting member (4), and includes punch elements (3a) lined up in a direction orthogonal to the relative movement direction; and punch element adjusting mechanisms that are disposed so as to correspond to the respective punch elements (3a) and adjusts positions of the punch elements (3a) relative to the punch supporting member (4) in the relative movement direction.