Propeller and system of counter-rotating propellers comprising improved means for limiting pitch, and a turbine engine comprising them

摘要

A propeller for an aircraft turbine engine, comprising means for adjusting the pitch of the blades comprising a hydraulic actuator borne by the rotor and including a cavity and a piston displaceable in said cavity and dividing said cavity into two chambers, as well as means for limiting the stroke of the piston in order to prevent displacement of said blades in a predetermined direction beyond a predetermined limiting pitch angle, and comprising hydraulic connection means with which both chambers may be put into communication with each other as soon as the pitch angle of the blades becomes equal to said predetermined limiting pitch angle during the displacement of said blades in said predetermined direction, these hydraulic connection means being borne by said rotor of the propeller.

主权项

1. A propeller for an aircraft turbine engine, comprising:
a first rotor; first blades borne by the first rotor and having an adjustable pitch angle; a first double acting hydraulic actuator borne by the first rotor and including a first cavity and a first piston slidably movable in the first cavity, wherein the first piston divides the first cavity into a first chamber and a second chamber, and the first piston is mechanically connected to the first blades so that the first piston changes the pitch angle of the first blades into a first pitch change direction when the first piston moves in a first displacement direction oriented from the second chamber towards the first chamber and vice versa, the propeller further comprising: a first couple of pressurized fluid inlet channels respectively connected to the first and second chambers of the first cavity whatever the position of the first piston, for moving the first piston, at least one first hydraulic circuit borne by the first rotor and including:
a first portion which is connected to a first region of the first cavity which belongs to the first chamber whatever the pitch angle of the first blades,a second portion connected to a second region of the first cavity which is located so that, when the first piston moves in the first piston displacement direction from a position in which the second region is initially part of the first chamber of the first cavity, the second region becomes part of the second chamber of the first cavity as soon as the pitch angle of the first blades becomes equal to a first it pitch angle, anda first valve commutable between a first operational mode and a second operational mode, wherein, in the first operational mode, the first valve connects the first and second portions of the first hydraulic circuit to one another so as to form a closed circuit, and wherein, in the second operational mode, the first valve isolates the first and second portions of the first hydraulic circuit from one another.