Propeller propulsion system for aircraft including means for adjusting the blade angle of the blades of the propeller and aircraft including such a propulsion system

1 . A propulsion system for an aircraft comprising:

a propeller mobile in rotation around a longitudinal axis, said propeller including a plurality of blades each having a blade axis globally perpendicular to the longitudinal axis, said blades of the plurality of blades being distributed angularly relative to said longitudinal axis; and

first means for adjustment of a blade angle of said blades of the plurality of blades, said first adjustment means configured to modify the blade angle of each blade of the plurality of blades as a function of an angular position of each said blade of the plurality of blades around said longitudinal axis,

wherein said first adjustment means include a globally tubular roller coaxial with said longitudinal axis, said globally tubular roller including on an external surface a housing configured to receive respective roots of said blades of the plurality of blades, said housing extending in a first plane having a non-zero angle (α) of which relative to a plane perpendicular to a reference plane containing said longitudinal axis is between −15° and +15°.

2 . The system as claimed in claim 1 , wherein said globally tubular roller is fixed in rotation around said longitudinal axis and said housing comprises a groove extending globally in said first plane, said roots of said blades of the plurality of blades are received in said groove so that said blades of the plurality of blades pivot around said roller and around said longitudinal axis, and the non-zero angle (α) of said first plane relative to said perpendicular plane is fixed, non-zero and between −15° and +15°.

3 . The system as claimed in claim 1 , wherein said globally tubular roller is fixed in rotation around said longitudinal axis and said housing comprises a groove extending globally in said first plane, said roots of said blades of the plurality of blades are received in said groove so that said blades of the plurality of blades pivot around said roller and around said longitudinal axis, and

wherein said first adjustment means are configured to modify the non-zero angle (α) of said first plane relative to said perpendicular plane between −15° and +15°.

4 . The system as claimed in claim 3 , wherein said first adjustment means include a transfer tube globally coaxial with said longitudinal axis, said globally tubular roller is mounted on and mobile in rotation on said transfer tube around a rotation axis perpendicular to said longitudinal axis,

wherein said transfer tube includes a first actuator including a first actuator chamber delimited by walls of said transfer tube and a first actuator piston received in said first actuator chamber and mobile in translation along said longitudinal axis in said first actuator chamber, and a free end of said first actuator piston connects, by a first link, to said globally tubular roller so as to cause said globally tubular roller to pivot relative to said transfer tube around said rotation axis and to modify the non-zero angle (α) of said first plane relative to said perpendicular plane.

5 . The system according to claim 1 , wherein said globally tubular roller is mobile in rotation around said longitudinal axis and said housing comprises a plurality of individual housings extending globally in said first plane,

wherein a root of each blade of the plurality of blades is received in one of said housings so that said blades of the plurality of blades pivot with said roller around said longitudinal axis, and

wherein said first adjustment means are configured to modify the non-zero angle (α) of said first plane relative to said perpendicular plane between −15° and +15°.

6 . The system as claimed in claim 5 , wherein said first adjustment means include a transfer tube mobile in rotation around said longitudinal axis, said globally tubular roller is mobile in rotation around said longitudinal axis and mobile in rotation on said transfer tube around a rotation axis perpendicular to said longitudinal axis,

wherein said first adjustment means further include an auxiliary transfer tube fixed in rotation relative to said longitudinal axis and extending coaxially with said transfer tube, said transfer tube mobile in rotation around said longitudinal axis inside said auxiliary transfer tube,

wherein said auxiliary transfer tube includes a second actuator including a second actuator chamber delimited by walls of said auxiliary transfer tube and a second actuator piston received in said second actuator chamber and mobile in translation in said second actuator chamber, and

wherein a free end of said second actuator piston connects, by a second link, to said globally tubular roller so as to cause said globally tubular roller to pivot relative to said transfer tube around said rotation axis and to modify the angle (α) of said first plane relative to said perpendicular plane.

7 . The system as claimed in claim 6 , wherein said globally tubular roller has a lateral face extending globally parallel to said first plane,

wherein said first adjustment means include a plate having a shape substantially corresponding to a shape of said lateral face, said plate mounted coaxially with said globally tubular roller,

wherein said plate is fixed in rotation about the longitudinal axis and relative to said globally tubular roller, and

wherein said plate includes a housing configured to receive an end of said second link opposite said second actuator piston.

8 . The system as claimed in claim 1 , further comprising:

second means for adjustment of the blade angle of said blades of the plurality of blades, said second adjustment means configured to move said globally tubular roller in translation along said longitudinal axis so as to modify, uniformly and simultaneously, the blade angle of all the blades of the plurality of blades of said propeller.

9 . The system as claimed in claim 8 , further comprising:

a casing,

wherein said second adjustment means include a third actuator including:

a third actuator chamber coaxial with said longitudinal axis and delimited by walls of said casing, and

a third actuator piston formed by a portion of said transfer tube, said third actuator piston received in said third actuator chamber and mobile in translation along the longitudinal axis in said third actuator chamber, said globally tubular roller configured to move along the longitudinal axis during a movement of said third actuator piston.

10 . An aircraft comprising:

at least one propulsion system as claimed in claim 1 .