Preloading device for a roller screw mechanism guided in rotation

A linear actuator comprising

• a roller screw mechanism guided in rotation with respect to a structure by means of a first and a second angular contact ball bearing, the roller screw mechanism comprising rollers interposed between an endless screw and a first and a second tapped ring which are joined together in rotation and free in translation,
• wherein the first and second tapped rings are secured to a respective ring of the first and of the second angular contact ball bearings,
• the linear actuator further comprising a single preloading device capable of applying load between the two rings of the first and of the second angular contact ball bearings respectively, thereby simultaneously allowing a loading of the roller screw mechanism and a rotational guidance of the roller screw mechanism with respect to the structure,
• wherein first and second angular contact ball bearing form a super duplex bearing type with a hard preloading;
• and
• wherein the preloading device comprises a bearing surface and an elastic ring clamping the two rings in contact with one another and comprising a set of clamping screws which are configured to apply load to the elastic ring.