US 12,330,769 B2
Electrohydraulic pitch setting with reversible pump
Huguette De Wergifosse, Moissy-Cramayel (FR); and Caroline Marie Frantz, Moissy-Cramayel (FR)
Assigned to SAFRAN AIRCRAFT ENGINES, Paris (FR)
Appl. No. 18/564,504
Filed by Safran Aircraft Engines, Paris (FR)
PCT Filed May 23, 2022, PCT No. PCT/FR2022/050972
§ 371(c)(1), (2) Date Nov. 27, 2023,
PCT Pub. No. WO2022/248800, PCT Pub. Date Dec. 1, 2022.
Claims priority of application No. 2105564 (FR), filed on May 28, 2021.
Prior Publication US 2024/0253770 A1, Aug. 1, 2024
Int. Cl. B64C 11/38 (2006.01); B64C 11/44 (2006.01); F01D 7/00 (2006.01); F04B 1/128 (2020.01); F04B 1/16 (2006.01); F04B 1/188 (2020.01); F04B 1/28 (2006.01)
CPC B64C 11/38 (2013.01) [B64C 11/44 (2013.01); F01D 7/00 (2013.01); F04B 1/128 (2013.01); F04B 1/16 (2013.01); F04B 1/188 (2013.01); F04B 1/28 (2013.01); F05D 2260/406 (2013.01); F05D 2260/79 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A pitch change mechanism for a propeller of a turbomachine the pitch change mechanism comprising an electrohydraulic actuator comprising:
an electric machine fixedly configured to be mounted on a stator part of a turbomachine and comprising an actuating shaft rotationally movable about an axis of rotation;
a pumping assembly comprising two axial-piston hydraulic pumps suitable for pressurizing a hydraulic fluid, each hydraulic pump comprising:
a barrel housed in a cavity filled entirely or partly with hydraulic fluid, the barrel being fixedly connected to the stator part of the turbomachine to prevent its rotation about the actuating shaft;
a set of cylinders formed inside the barrel each cylinder housing a piston movable in translation in the cylinder and comprising an intake hole configured to receive hydraulic fluid coming from the cavity, and a discharge hole configured to send hydraulic fluid to an actuator of the propeller;
a plate inclined with respect to the axis of rotation and rotationally secured to the actuating shaft, each piston bearing on a surface of the plate;
wherein the plate of a first of the pumps comprises a curved intake opening extending circumferentially with respect to the axis of rotation and configured to allow the circulation of the hydraulic fluid from the cavity to the cylinders of the first of the pumps when the plate of said pump is driven in a first direction of rotation, and the plate of a second of the pumps comprises a curved intake opening extending circumferentially with respect to the axis of rotation and configured to allow the circulation of the hydraulic fluid from the cavity to the cylinders of the second of the pumps when the plate of said pump is driven in a second direction of rotation opposite to the first direction of rotation.