VARIABLE-PITCH MECHANISM FOR THE BLADES OF A SYSTEM OF CONTRAROTARY FANS AND SYSTEM OF CONTRAROTARY FANS COMPRISING AT LEAST ONE SUCH MECHANISM

摘要

Variable pitch mechanism for the blades of a fan (16) of a system of contrarotary fans for a turbomachine, each blade (16a) being able to move about a radial axis (Y), said mechanism comprising a linear actuator, means (56) for converting the movement delivered by the linear actuator into a rotation of each of said blades (16a) in a way that is synchronized about their radial axis (Y), said means comprising a fitting (48) of longitudinal axis (X) formed of a central annulus (50), of an outer annulus (52), and of a plurality of radial arms (54) rigidly connected to the central annulus (50) and to the outer annulus (52), said central annulus (50) being intended to receive the actuation of the linear actuator, said central annulus (50) and said outer annulus (52) being arranged in two distinct planes both orthogonal to the longitudinal axis (X) such that the fitting (48) has the shape of a cone frustum.