Propeller provided with interchangeable blades and a method of mounting interchangeable blades on a propeller

Patent metadata

Field	Value
Publication number	US-12179906-B2
Application number	US-202318302139-A
Country	US
Kind code	B2
Filing date	Apr 18, 2023
Priority date	Jun 27, 2019
Publication date	Dec 31, 2024
Grant date	Dec 31, 2024

Abstract

A propeller provided with interchangeable blades, and to a method of mounting such interchangeable blades on the propeller. The propeller comprises a hub, fastening fittings, rotation guide devices for guiding the fastening fittings in rotation relative to the hub, locking parts, and blades. The fastening fittings are configured to be assembled into the hub from the inside of the hub, and the locking parts lock respective ones of the fastening fittings onto the hub. The blades are fastened to respective ones of the fastening fittings outside the hub and can thus easily be replaced with other blades without removing the propeller.

First claim

What is claimed is:

1. A propeller of an aircraft, which propeller is provided with interchangeable blades and comprises:
a hub;
at least two blades;
one fastening fitting per blade;
one rotation guide device per blade, each of the rotation guide devices being arranged between the hub and a respective fastening fitting; and
first fastening devices for fastening the at least two blades, and interconnecting each of the at least two blades and a respective one of the fastening fittings so as to secure each blade to a fastening fitting and so as to couple each blade to the hub via a respective fastening fitting;
wherein the first fastening devices are arranged outside the hub;
wherein each fastening fitting includes a pitch control finger and the propeller includes a pitch control device arranged inside the hub and co-operating with the pitch control finger of each of the fastening fittings in order to change the pitch of each blade.

2. The propeller according to claim 1 ,
wherein each rotation guide device comprises an inner ring, an outer ring, and rolling elements, the inner ring being secured to or integral with a respective one of the fastening fittings and the outer ring being secured to or integral with the hub.

3. The propeller according to claim 2 ,
wherein the inner ring is made in one piece.

4. The propeller according to claim 1 ,
wherein each fastening fitting includes at least one rod configured to receive at least one balancing weight designed to balance an assembly made up of a fastening fitting and of a blade firstly about the pitch axis of the blade and secondly about the axis of rotation of the hub.

5. The propeller according to claim 1 ,
wherein the propeller further comprises one locking part per blade, each locking part being arranged outside the hub and providing an axial abutment along the pitch axis of the respective blade and going towards the inside of the hub so as to lock a respective fastening fitting radially onto the hub in the direction going towards the inside of the hub.

6. The propeller according to claim 1 ,
wherein the propeller further comprises second fastening devices, each of the second fastening devices interconnecting the locking part and the fastening fitting in order to secure the locking part to the fastening fitting.

7. The propeller according to claim 1 ,
wherein each locking part includes at least one rod configured to receive at least one balancing weight designed to balance an assembly made up of a fastening fitting, of a locking part, and of a blade about the axis of rotation of the hub.

8. A method of assembling the propeller of an aircraft, which propeller is provided with interchangeable blades and comprises:
a hub;
at least two blades;
one fastening fitting per blade; and
one rotation guide device per blade;
wherein the method comprises the following steps:
inserting each fastening fitting into the hub from the inside of the hub;
mounting the at least two blades into respective ones of the fastening fittings outside the hub; and
securing the blades to the respective ones of the fastening fittings;
wherein the method further comprises an additional step of fastening at least one balancing weight to at least one of the fastening fittings and/or, when the propeller has locking parts, to at least one of the locking parts.

9. The method according to claim 8 ,
wherein method further comprises a step of positioning a respective guide device between each of the fastening fittings and the hub.

10. The method according to claim 9 ,
wherein, with each of the guide devices comprising an inner ring, an outer ring and rolling elements, the step of positioning a guide device comprises the following three sub-steps:
assembling the outer ring of each of the guide devices into the hub;
assembling the inner ring of each of the guide devices onto a respective one of the fastening fittings; and
assembling the rolling elements of each guide device onto the inner ring or indeed into the outer ring of the guide device.

11. The method according to claim 8 ,
wherein the method further comprises a step of mounting each of the locking parts onto the respective ones of the fastening fittings outside the hub so as to lock the fastening fittings radially onto the hub in the direction going towards the inside of the hub and providing an axial abutment along the pitch axis of the respective blade and going towards the inside of the hub.

12. The method according to claim 11 ,
wherein the method further comprises an additional step of securing each of the locking parts onto the respective ones of the fastening fittings.

13. A propeller for an aircraft, the propeller having interchangeable blades and comprising:
a hub;
at least two blades, each of the at least two blades having a longitudinal axis;
one fastening fitting per blade, each fastening fitting includes a pitch control finger and the propeller includes a pitch control device arranged inside the hub and co-operating with the pitch control finger of each of the fastening fittings in order to change the pitch of each blade;
one rotation guide device per blade, each of the rotation guide devices being disposed between the hub and a respective one of the fastening fittings; and
first fastening devices for fastening the at least two blades, and interconnecting each of the at least two blades and a respective one of the fastening fittings to secure each blade to a respective one of the fastening fittings to couple each blade to the hub via a respective one of the fastening fittings;
wherein the first fastening devices are disposed outside the hub and extend from a first end to a second end in a direction different than the direction of a chord of the blade.

14. The propeller according to claim 13 ,
wherein each of the fastening fittings have opposed and space apart first and second plates extending radially in a direction away from the hub, with each of the plates having a hole that a respective one of the first fastening devices extend through such that the first end of the respective first fastening device is adjacent the first plate and the second end of the respective first fastening device is adjacent the second plate.

15. The propeller according to claim 13 , wherein each of the fastener fittings have spaced apart holes, with a respective one of the first fastening devices extending through the holes in the respective one of the fastener fittings in a direction substantially perpendicular to a respective one of the longitudinal axes of the direction of a chord of a respective one of the at least two blades.

16. The propeller according to claim 13 , wherein each rotation guide device comprises an inner ring, an outer ring, and rolling elements, the inner ring being secured to or integral with a respective one of the fastening fittings and the outer ring being secured to or integral with the hub, and wherein the first fastening devices extend in direction substantially perpendicular to a respective one of the longitudinal axes of a respective one of the at least two blades.

Assignees

• Airbus Helicopters

Inventors

• Grant Scott
• Fournier Mathias
• Berthalon Sylvain

Classifications

• B64C11/32

  mechanical · CPC title

• B64C11/008

  characterised by vibration absorbing or balancing means · CPC title

• B64C27/48

  Root attachment to rotor head · CPC title

• B64C11/06 Primary

  for variable-pitch blades · CPC title