PROTECTOR MEANS FOR TOOL SETS IN HYDRAULIC PRESS

摘要

An arrangement for protecting tools in a hydraulic press against overloading if an object is present in a tool space of the hydraulic press. A displacement switch monitors at least a portion of a path of movement of a press ram with an additional switching device providing an output signal during a predetermined movement of the press ram. A control circuit evaluates a sequence of the output signals of the displacement switch and additional switching device in such a manner that a fault signal is formed when the additional switching device provides an output signal prior to an output signal from the displacement switch. The additional switching device may be constructed as a switch element which provides an output signal in dependence upon a pressure or a speed of flow of a pressure medium in a hydraulic circuit.