Task Robots are frequently used – in particular in the automotive industry – with exchangeable tools. Since the tool change procedure may not delay or even interrupt the production process, the interface between robot arm and tool has to be constructed in such a way that this change can be accom-plished easily and quickly. So-called multi-couplings for sup-ply voltages, control signals, pneumatics and hydraulics help to facilitate this process. The mechanical connection between robot arm and tool is usually done by gripping a bolt, which is attached to the tool. The grip mechanism is activated and the pin is seized by triggering a pneumatic cylinder. The reversing of the pneu-matic cylinder again causes the tool to be put back in place. The compressed air supply, which is necessary for the grip mechanism, has to be available only during the coupling and uncoupling procedure. For safety reasons it has to be switched-off during the use of the tool, so that an inadvertent throwing-off is prevented. For this, a pneumatic valve is connected before the grip mechanism, which is activated only during the coupling and uncoupling procedure. This means that the pneumatic valve is activated only within a limited range.