Translation block with disengaging nut for screw-mounted lifting mechanism

A screw driven translation block with a disengageable nut, for supporting a load on a vehicle, comprising:

• a nut (15) having an external surface formed by longitudinal, axial grooves (42) separated by toothed elements (43);
• a mechanical body (4) housing said nut (15), said mechanical body being in slidable contact with a guide element (7);
• a screw (13), for rotationally driving said nut (15) and said mechanical body (4), in threaded communication with said nut (15) such that said screw traverses said mechanical body (4);
• and,
• an immobilizing and releasing device in communication with said nut (15) and said mechanical body (4) for at least one of immobilizing and releasing said nut (15) from rotation about said screw (13), said immobilizing and releasing device having:
• a rotating connector for joining a free, loaded end of said nut (15) to an adjacent transverse wall of said mechanical body (4);
• a flexible connection for joining said rotating connector to an upper portion of said adjacent transverse wall of said mechanical body (4);
• at least two pivoted flanges (20, 21), each of said pivoted flanges (20,21) having a free end pivoting about an axis parallel to the rotation axis of said nut (15), each pivoted flange (20,21) having an associated inflatable tube (48, 49), the free end of each articulated flange being biased by a spring into engagement with one of said axial grooves (42) of the nut (15) to prevent rotation of the nut (15) in at least one direction, and each of the associated inflatable tubes, when inflated, biases the free end of the associated pivoted flange out of engagement with the axial grooves (42) to facilitate rotation of said nut (15) in at least one direction.