Control device for an eddy current coupling

摘要

A control device for an eddy current coupling (10) whose pole element (12) is driven by an electric motor (11) at a constant speed of rotation and whose rotor (13) generates a torque for a lift drive for holding a load (1) in a central position and for lifting and lowering this load starting from the central position and the exciter current of the exciter winding of the pole element (12) is controlled for this purpose by a speed of rotation control circuit in such a way that when the rotor (13) is stationary a torque is produced of such magnitude that the load (1) remains in the position it has taken up and this torque is increased in order to lift the load and reduced in order to lower the load, is constructed in such a way that the speed of rotation controller (24) has subordinated to it a torque controller (26) which forms from the sum of the initial value of the speed of rotation controller (24) and the constant stopping torque reference value with an approximated torque actual value a comparison value which influences the exciter current in such a way that the required reference torque is obtained. <IMAGE>