| 摘要 |
In the case of a method for automatically controlling an electrohydraulic pressing tool, in particular for producing pipe connections, to actuate the pressing tool a hydraulic piston is moved, in that fluid is pumped into a hydraulic cylinder by a hydraulic pump driven by an electric motor. When a limiting pressure in the hydraulic cylinder is reached, a pressure relief valve opens, and so the hydraulic fluid can flow into a reservoir. With the aid of a control device, a current drop at the motor is detected when the valve opens. The electric motor is switched off when the current falls by a predetermined value (DeltaI) and/or decreases over a predetermined time period (Deltat) after reaching a limiting current. |
