Safety screw assembly and operating key thereof

A safety screw assembly (1) and operating key (9;

• 90) thereof, comprising:
• a screw (1) formed of a body (2) and a head (3), the head (3) being movable between a first position where it is rotationally integral with the body (2) and a second position where it is freely rotatable, the head (3) having, on one face (5), an opening (6) or a relief, the shape of which matches a relief (10;
• 100) or an imprint formed on part of said operating key (9;
• 90), wherein one end (4) of the body (2) of the screw (1) comprises a first part (4, 18, 20, 21, 22, 23) called the stator, and a second rotationally movable part (25), called the rotor, with the head (3) of the screw (1) defining a housing element for receiving the rotor (25), and in that the assembly comprises a translationally movable securing component (37), said component (37) being movable between a first securing position, called the loose position, in which the head (3) is freely rotatable and the rotor (25) and the stator (18, 20, 21, 22, 23) are rotationally integral, and a second position, called the locked position, in which at least the head (3) and the stator (4, 18, 20, 21, 22, 23) are rotationally integral, and in that the key (9;
• 90) has at least one component (11;
• 110) for setting the rotor (25) into rotation, wherein the stator (4, 18, 20, 21, 23) comprises two cylindrical parts with a circular base (22, 23), a smaller-diameter part (22) having a bottom (19) with at least two wells (18) forming housing elements receiving translationally movable pistons in a direction parallel to the longitudinal axis (A2) of the body (2).