Clamp force control for load-handling device

A control for a load-handling device including a hydraulic gripper adapted on the one hand to firmly grip an object by means of pressure in a clamping pressure line leading to one or more hydraulic cylinders that actuate gripping arms on the gripper, and on the other hand to lift said object by actuation from a hydraulic lifting device comprising:

• sensor means for detecting the lifting force exerted by the lifting device;
• control means for controlling a pressure reduction valve to a pressure in the clamping pressure line during a clamping and lifting sequence such that said object is not deformed;
• said sensor means is a pressure sensor sensing the prevailing pressure in the lifting device;
• and
• said control means, during said sequence until said object is leaving a supporting surface, being adapted to control the pressure reduction valve to a pressure in the clamping pressure line by an adjustable preset proportion of said detected lifting force, such that the clamping force of the gripper is continuously adapted to the lifting force and that said object is not allowed to slip downwards between the gripping arms.