Abstract: Method of correcting a bending operation performed by a press brake, the bottom beam of which contains deformation compensation cylinders, in which a calibration nomogram is pre-recorded using very short calibration pieces, this nomogram establishing a correspondence between the forces measured at the side frames and the pressures applicable to the compensation cylinders in order to keep the bottom beam substantially straight. During a subsequent bending operation, pressure values resulting from this nomogram are applied to the compensation cylinders according to the forces measured at the side frames. A bottom dead center is recalculated by taking account of the deformation of the top beam, the deformation of the side frames, the actual length and thickness of the piece, and the spring effect.

Abstract: Method of correcting a bending operation performed by a press brake, the bottom beam of which contains deformation compensation cylinders, in which a calibration nomogram is pre-recorded using very short calibration pieces, this nomogram establishing a correspondence between the forces measured at the side frames and the pressures applicable to the compensation cylinders in order to keep the bottom beam substantially straight. During a subsequent bending operation, pressure values resulting from this nomogram are applied to the compensation cylinders according to the forces measured at the side frames. A bottom dead centre is recalculated by taking account of the deformation of the top beam, the deformation of the side frames, the actual length and thickness of the piece, and the spring effect.

Abstract: A method for setting the travel of a press brake comprising at least one sensor, which measures a physical parameter (p) that varies with the force exerted by the punch on a piece of sheet metal placed on the die, and an electronic device that controls the displacement of the mobile apron. Instantaneous bending angle ? under load of the piece is calculated as a function of the displacement; the bearing force (f) of the punch on the piece is calculated using the value of the physical parameter (p); the sequence of values for the instantaneous bending angle/bearing force pair (?, f) is compared to a reference curve (?, f)ref which is pre-recorded during a bending operation involving the same material, and the electronic device calculates a bottom dead center correction taking account of the deviation between the (?, f) pairs and reference curve (?, f)ref.

Abstract: The invention relates to a method for setting the travel of a press brake comprising at least one sensor, which measures a physical parameter (p) that varies with the force exerted by the punch on a piece of sheet metal placed on the die, and an electronic device that controls the displacement of the mobile apron between a top dead center and a bottom dead center (BDC). Said electronic device is provided with computing means for correcting the bottom dead center value according to the measurement taken for said displacement and for the physical parameter (p).

Abstract: A method of adjusting the stroke of a press brake having a movable beam (1) supporting a punch (2), a fixed beam (3) supporting a die (4), means of displacing (5, 5′) the movable beam with respect to the fixed beam, said displacement means resting on side frames (6, 6′) immovably attached to the fixed beam, linear encoders (9, 9′) for measuring the displacement of the movable beam with respect to the side frames, at least one sensor (8, 8′) measuring a physical parameter (p) varying with the force exerted by said punch on a metal sheet placed on said die, and an electronic device for controlling (7) the bending movement controlling the speed of said displacement movement between top dead center and bottom dead center (BDC), provided with a calculation means for correcting the value of said bottom dead center depending on the measurement of said displacement and said physical parameter.

Abstract: A method of adjusting the stroke of a press brake having a movable beam (1) supporting a punch (2), a fixed beam (3) supporting a die (4), means of displacing (5, 5′) the movable beam with respect to the fixed beam, said displacement means resting on side frames (6, 6′) immovably attached to the fixed beam, linear encoders (9, 9′) for measuring the displacement of the movable beam with respect to the side frames, at least one sensor (8, 8′) measuring a physical parameter (p) varying with the force exerted by said punch on a metal sheet placed on said die, and an electronic device for controlling (7) the bending movement controlling the speed of said displacement movement between top dead center and bottom dead center (BDC), provided with a calculation means for correcting the value of said bottom dead center depending on the measurement of said displacement and said physical parameter.

Abstract: The present invention relates to a measuring device for the bend angle of a metal sheet or plate in a press brake of the type having a reciprocable punch with a sharp bending edge, and a die having two bending edges on either side of a substantially V-shaped groove or channel, the measuring device comprising a rotatory measuring element, the cross-section of which has a circular peripheral part centered around the axis of rotation of the measuring element, and a linear peripheral part which is shorter than the diameter of the circular peripheral part.