The production of complex sheet metal parts with a high degree of forming and in large quantities is often carried out on progressive presses in successive forming operations. To achieve the desired geometry, the workpiece undergoes operations such as cutting, deep drawing, stretching, and bending. To minimise downtime between forming processes, the workpieces are automatically transported from one forming stage to the next using multi-axis transfer systems. These systems grip the workpiece after the tool opens, move it to the next stage, and place it there. During this transfer process, secure handling of the workpieces must be ensured.
The dynamic vibration characteristics of the transfer system, the machine due to the forming processes, and the sheets themselves play a role as disturbances. In particular, the high strength of the sheet materials and the demands for high cycle rates represent major challenges. In summary, these vibrations can lead to positioning inaccuracies, distortion of the sheets being transported, or even result in the workpieces falling out of the grippers, leading to increased scrap production and, at worst, machine failures.
As part of a research project, the use of an active gripper system between the transfer beams and sheet metal workpieces for vibration damping is being investigated. The aim is to achieve a vibration-minimised transfer of sheet metal workpieces in progressive presses, which would increase the productivity and process reliability of these presses.
