Realizzazione di una pressa “intelligente” per il controllo del ritorno elastico nel processo di piegatura

The hydraulic press brake for sheet metal bending has been designed for laboratory research and not for production aims; in particular, to perform accurate measurements of force during the operation of bending and then to validate and possibly to optimize the semi-empirical procedure created to solve the problem of springback. To understand the reasons for the design and implementation of a press brake is necessary to recall the problems that occur during the bending process. In particular, the springback phenomenon is seen in a negative way and one should try to reduce it as much as possible. This explains the use of the term " intelligent press brake" because it is necessary to create a system capable of acquiring all the information on the material being processed at an early stage of the process. The relevant data are then used as input to a prediction algorithm on the displacement to be imposed to the punch. The method used is semi-empirical method. The information relating to the properties of the material being processed is collected. Through the information of the material and the FEM simulations pre-loaded in the software of the press, the algorithm provides the value of the stroke of the punch needed to obtain the desired bending angle (considering also the elastic recovery). In the algorithm, the both linear and second degree interpolations are used. In the model, only the properties of the material have been included while it was not considered the effect of geometrical parameters, as the thickness sheet and the geometry of the tool (punch radius and die). The output parameters are the angle of springback and the properties of the material. The objective is therefore to improve the evaluation of the stroke of the punch considering the properties of the material through the direct measurement of load an