To effectively execute the relaxation of an impact energy at the time of changing the rotating direction of a reversible rotating mill and at the time of biting into rolls and to facilitate the maintenance and the checking by arranging a receiving pressure buffering mechanism composed of a cover body and a spring for supporting the cover body to a pressure receiving plate of a coupling at a roll side.

The receiving pressure buffering mechanism 10 is arranged to the pressure receiving plate 4 of the coupling at the roll side. The receiving pressure buffering mechanism 10 is composed of the cover plate 11 and the spring 12 supporting the cover plate 11 and arranged on the both surfaces of the pressure receiving plate 4. Concretely, a recessed part 13 is widely arranged at almost the center part of the pressure receiving furnace, and the cover plate 11 is fitted into the recessed part 13. A spring holding part 17 is arranged to the recessed part 13 and the cover plate 11, and the spring 12 is hold therein. At the time of transmitting the rotating torque from the spindle side to the roll side, the spring 12 is compressed through the pressure receiving plate 4, and a gap C between the bottom surface of the recessed part 13 in the pressure receiving plate 4 and the rear surface of the cover plate 11 is eliminated, and the shock are absorbed and relaxed by the spring 12 in the interval till closely contacting the back plate 11 with the pressure receiving plate 4.