Device for feeding fluid to a hydraulic actuator for controlling the pitch of the fan blades of a two-propeller turboprop

1. A device for feeding fluid to a hydraulic actuator for controlling a pitch of fan blades of a two-propeller turboprop, the device comprising:

a fluid manifold constrained to rotate with a rotor of the turboprop and including a cylindrical portion provided on an outside surface including at least two annular fluid-circulation grooves that are longitudinally spaced apart, each fluid-circulation groove presenting at least one outlet orifice opening out radially to an inside of the cylindrical portion of the fluid manifold;

a fluid-admission support secured to a stationary portion of the turboprop and including a cylindrical portion arranged around the cylindrical portion of the fluid manifold, being coaxial therewith and including at least two distinct fluid passages opening out to respective fluid-admission tubes and each leading radially to an inside of the cylindrical portion of the support in a respective one of the fluid-circulation grooves of the manifold; and

a tub constrained to rotate with the fluid manifold and including a central portion arranged inside the cylindrical portion of the manifold, being coaxial therewith, and provided on an outside surface and including at least two longitudinal fluid-flow channels each fed with fluid via a respective one of the outlet orifices of the fluid manifold, each fluid-flow channel having a longitudinal end leading to a chamber of a control actuator.

2. A device according to claim 1 , further comprising a fluid distributor including a cylindrical portion interposed radially between the respective cylindrical portions of the fluid manifold and of the fluid-admission support, being coaxial therewith.

3. A device according to claim 2 , wherein the cylindrical portion of the fluid distributor includes, for each fluid-circulation groove of the manifold, a plurality of orifices that are regularly distributed on an outside surface.

4. A device according to claim 1 , wherein the cylindrical portion of the fluid manifold is extended at one of its longitudinal ends by a radial portion including at least two ducts for passing fluid, each fluid-passing duct opening into a fluid-flow channel of the tub and leading to a control actuator chamber.

5. A device according to claim 1 , wherein the cylindrical portion of the fluid-admission support is extended at one of its longitudinal ends by a radial portion for fastening to a stationary portion of the turboprop.

6. A device according to claim 1 , further comprising ball bearings arranged between the fluid manifold and the fluid-admission support.

7. A device according to claim 1 , wherein the fluid passages of the fluid-admission support are regularly spaced apart from one another.

8. A device according to claim 1 , wherein the fluid-circulation grooves of the fluid manifold are defined longitudinally relative to one another by at least three annular gaskets arranged on the outside surface of the cylindrical portion of the manifold and projecting radially outwards therefrom.

9. A two-propeller turboprop comprising:

first and second sets of adjustable-pitch fan blades driven in rotation by a rotor of a power turbine;

two hydraulic actuators for controlling the pitch of the fan blades and centered on a longitudinal axis of the turboprop; and

a device according to claim 1 for feeding fluid to the actuators.

10. A turboprop according to claim 9 , wherein the rotor of the power turbine drives rotation of the sets of fan blades via a step-down epicyclic gear train.