The coupling includes first gripping members which are connected, facing on one and the same level on corresponding mounting bodies, to respective structures, and second gripping members mounted so as to slide vertically on the first gripping members in order to secure pneumatic covers in two diametrically opposed regions thereof with the collaboration of threaded rods. The gripping members and provide retention walls that extend towards the mounting bodies by means of horizontal retention flanges. The second gripping members have walls with holes for the passage of screws during fitting thereof to the mounting bodies.
