Patent attributes
The invention relates to a method for controlling swaying and swinging of a spreader in a crane and the load attached thereto, the crane comprising: a trolley, hoist gears, hoisting ropes, on which the spreader is suspended from the trolley, auxiliary gears provided with motors and motor control equipment and auxiliary ropes, and in which method the forces of the auxiliary ropes exerted on the spreader are controlled by moving the auxiliary ropes using the auxiliary gears by means of torque instructions (Tcontrol) obtained on the basis of the rope forces (Frope) of the auxiliary ropes and the rotating speed data of the auxiliary gears, and whereby the rotating speed data of each auxiliary gear is formed gear-specifically as the difference between the measured rotating speed (nact) of the auxiliary gear and the calculated rotating speed (ncalc) of the auxiliary gear.