Roller screw mechanism with cage

A valve operator assembly for a valve comprising:

• a valve body, and a valve translating member axially moveable, the assembly further comprising:
• a housing adapted to be mounted on the valve,
• an operable input member rotatably mounted with respect to the housing;
• a roller screw mechanism having:
• a screw provided with an outer thread,
• a nut surrounding and coaxial with the screw, the nut being provided with an inner thread;
• a plurality of rollers radially disposed between the screw and the nut and each provided with an outer thread engaging the outer and inner threads and with two outer gear teeth, the mechanism further providing two synchronization gear teeth meshing with the gear teeth of the rollers;
• one retaining cage for the rollers having a plurality of pockets spaced apart one with another in the circumferential direction;
• at least the outer thread of each roller being located inside the associated pocket of the cage;
• and
• the screw, or the nut, of the mechanism being adapted to be connected to the valve translating member of the valve, and the nut, or the screw, of the mechanism being connected to the input member.