Individual pitch control device for blades of rotors of rotor craft by means of rotating linear jacks

An individual pitch control device for the blades (7) of a rotor of a rotor craft, said rotor having a plurality of independently controlled blades, comprising, for each blade (7) of the rotor, a respective dual-action, electrohydraulic linear jack (29) with at least one body, for controlling the collective, monocyclic and, if appropriate, multicyclic pitch in a rotating reference system of said blade, said jack (29) being driven in rotation with the rotor about an axis (A) thereof and disposed substantially longitudinally with respect to a rotor mast (1), and outside said rotor mast, wherein each jack (29) is implanted, via one of two elements formed by a respective cylinder (30) and rod (31), on a rotating support (25) surrounding the rotor mast (1) and driven in rotation with the rotor about the axis (A) thereof, whilst the other of said two elements of the jack (29) is connected to a pitch control lever (24) of the corresponding blade, further comprising at least one hydraulic collector (27) which is annular and inserted between said rotating support (25) and a fixed support (4), said annular hydraulic collector being partially integrated in at least one of said rotating support and said fixed support.