The hysteresis cable reel generates output torque through the relative rotation of the magnetic field between the induction disk and the permanent disk through the hysteresis coupler, and the torque can be adjusted through the air gap. When the main engine is powered off and stopped, due to inertia, there is still a period of magnetic field torque in the magnetic coupling, which can not only reduce the damage to the cable due to the asynchronous between the main engine and the cable, but also ensure that the cable will not break down by cooperating with the phase bearing. It is widely used in port gantry cranes, container bridge cranes and other mobile lifting equipment.