building up in the supply line 38 on the piston rod side the overpressure valve 82 opens so that hydraulic fluid flows into the supply line on the piston side and from there into the hydraulic tank 30 with the result that the speed of displacement of the hydraulic cylinder 24 is reduced because the volumetric flow rate of the hydraulic fluid present in the supply line 38 on the piston rod side is reduced this means that the quantity of hydraulic fluid which flows info the chamber of the hydraulic cylinder on the piston rod side is reduced and as a result the actuation of the hydraulic cylinder 24 in this case retracting the hydraulic cylinder 24 is slowed down of course the arrangement of the check valve 58 and the electro hydraulic overpressure valve 62 can be in the opposite sense so that hydraulic fluid can flow from the supply line 40 on the piston side into the supply line 38 on the piston rod side in this case extension of the hydraulic cylinder 24 would then be slowed down control of the overpressure valve 62 takes place through the electronic control unit 64 which for its part receives control signals from a bad case sensor 66 depending on the load condition the sensor 86 indicates a more or less critical load condition as the critical load condition is approached the control input transmitted by the electronic control unit 84 for adjusting the overpressure valve 82 is strengthened which then causes the valve to be opened further so that the discharge volumetric flow rate increases the adjustment or the increase of the control input in this case preferably takes place proportionally to the signal provided.