Propeller for an aircraft turbo engine, including safety means for controlling blade angle of attack

Patent metadata

Field	Value
Publication number	US-10640198-B2
Application number	US-201715495444-A
Country	US
Kind code	B2
Filing date	Apr 24, 2017
Priority date	Apr 28, 2016
Publication date	May 5, 2020
Grant date	May 5, 2020

Abstract

In order to simplify the design of an aircraft turbo engine propeller while enhancing the safety function thereof related to control of the blade angle of attack, a propeller is provided comprising a secondary rotational coupling to couple in rotation, along the radial axis of the blade, the inner radial end of the blade root with a mechanical joining member of a blade angle of attack control device, the secondary coupling being designed and configured to be active in the event of failure of the main pin.

First claim

The invention claimed is:

1. A propeller for an aircraft turbo engine comprising:
a hub centered on an axis of rotation of the propeller;
a plurality of propeller blades, each having a blade root with an inner radial end, and, associated with at least one of said blades:
each of the blades configured to vary a blade angle of attack by pivoting about a radial axis of said blade, the blade being joined at the inner radial end of the blade root to a mechanical joining member;
a main pin for retention of the blade in a radial direction thereof, said main retention pin coupling, in translation and in rotation, along the radial axis of the blade, the blade root to the mechanical joining member; and
a secondary pin for retention of the blade in the radial direction thereof, said secondary pin being designed and configured to be active in the event of failure of the main pin, and
a secondary rotational coupling to couple in rotation, along the radial axis of the blade, the inner radial end with the mechanical joining member said secondary rotational coupling being configured to be active in the event of failure of the main pin;

Wherein the blade is configured to vary the blade angle of attack via torque acting on the main pin or, in the event of failure of the main pin, the second rotational coupling.

2. The propeller according to claim 1 , wherein the inner radial end and the mechanical joining member define a male/female assembly constituting all or part of the secondary rotational coupling, by virtue of an interface of non-circular cross section.

3. The propeller according to claim 2 , wherein the cross section includes at least one straight portion.

4. The propeller according to claim 2 , wherein the cross section has an overall shape which is one of elliptical or polygonal.

5. The propeller according to claim 1 , wherein the secondary rotational coupling comprises:
a coupling member extending in the radial direction of the blade and being rigidly secured in rotation to one of the elements, either the inner radial end or the mechanical joining member; and
a groove extending in the radial direction of the blade and made on the other of the elements, either the inner radial end or the mechanical joining member, said coupling member being housed in the groove.

6. The propeller according to claim 5 , wherein the coupling member is one of a key or a rib made as a single piece with said one of the elements, either the inner radial end or the mechanical joining member.

7. The propeller according to claim 1 , further comprising:
a hollow member forming an integral part of the hub and defining a receiving cavity through which the blade root passes; and
a rotation guide device for the blade root, the rotation guide device being housed in said receiving cavity, between a side wall of the hollow member and the blade root,
wherein, in an assembled configuration of the propeller, said receiving cavity has said secondary retention pin, said secondary retention pin passing through a receiving orifice of the blade root, and being arranged, in the radial direction, at a distance from a radial abutment element formed by the hollow member, and
wherein the side wall of the hollow member has an orifice for insertion of the secondary retention pin into the receiving cavity, the insertion orifice being configured in such a way that the secondary retention pin passes through the latter when the propeller is, during assembly, in a configuration for mounting the secondary retention in in which the insertion orifice is aligned with the receiving orifice of the blade root, and
wherein the propeller is configured so as to have, in the assembled configuration, an offset in the radial direction between the insertion orifice and the receiving orifice of the blade root.

8. The propeller according to claim 1 , further comprising:
a hollow member forming an integral part of the hub and defining a receiving cavity through which the blade root passes; and
a rotation guide device for the blade root, the rotation guide device being housed in said receiving cavity, between a side wall of the hollow member and the blade root, and
wherein, in an assembled configuration of the propeller, said receiving cavity has said secondary blade retention pin passing through a receiving orifice of the blade root, and being arranged, in the radial direction, at a distance from a radial abutment element forming an end wall of the hollow member, the blade root passing through the radial abutment element, which is mounted removably on the side wall of the hollow member.

9. The propeller according to claim 7 , wherein the rotation guide device for the blade root is mounted by screwing in the receiving cavity.

10. The propeller according to claim 1 , further comprising a rotation drive shaft centered on the axis of rotation, around which is arranged the blade angle of attack control device.

11. An aircraft turbo engine comprising a propeller according to claim 1 , wherein said turbo engine comprises a receiver with two contra-rotating open propellers.

12. An aircraft comprising:
A fuselage; and
at least one turbo engine according to claim 11 .

Assignees

• Airbus Operations Sas

Inventors

• Colmagro Jerome

Classifications

• B64C11/32 Primary

  mechanical · CPC title

• B64C11/48

  Units of two or more coaxial propellers · CPC title

• B64C11/06 Primary

  for variable-pitch blades · CPC title

• B64D27/14

  within, or attached to, fuselages · CPC title

• B64C11/30 Primary

  Blade pitch-changing mechanisms · CPC title