| 摘要 |
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). The difference in thickness between the real thickness of the sheet metal and the set value (e) for the sheet metal thickness is measured during bending; instantaneous bending angle alpha under the load of the piece is calculated as a function of the displacement, taking account of said difference in thickness and the geometric parameters of the punch and the die; 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 (alpha, f) is taken and compared to a reference curve (alpha, f)ref which is pre-recorded during a bending operation involving the same material, and the electronic control device calculates a bottom dead center correction taking account of the deviation between the (alpha, f) pairs and reference curve (alpha, f)ref, said difference in thickness and the deformations in the press.
|
