Device and method for preventing a tool from breaking during fine cutting and/or forming a work piece

摘要

An exchangeable plate is suspended on a top plate and held in a lower end position without force by a hydraulic clamping means. In an upper end position, it is connected with force fit to, and re-detached from, the top plate as a function of a stripping operation of a scrap web from a V-ring pressure plate. The exchangeable plate is transferred from the lower into the upper end position by movement of a ram, and transferred from the upper into the lower end position by gravity. A sensing distance, adapted to the brake path of the drive system, is provided between the top plate and the exchangeable plate. A sensing device in the V-ring pressure plate outputs a signal to the computer for stopping the drive system and deactivating the hydraulic system. A sensor detects premature movement of a pressure plate in the exchangeable plate.