Composite aircraft propeller blade with an integrated spar

Patent metadata

Field	Value
Publication number	US-11155336-B2
Application number	US-201916245875-A
Country	US
Kind code	B2
Filing date	Jan 11, 2019
Priority date	Jan 12, 2018
Publication date	Oct 26, 2021
Grant date	Oct 26, 2021

Abstract

A reinforcing fiber structure for a propeller blade made of composite material is woven as a single piece to have an airfoil, a spar portion, and an enlarged portion. The fiber structure includes a zone of non-interlinking extending between the front and rear edges of the airfoil, and extending between an intermediate zone and the bottom edge of said airfoil. The spar portion extends inside the airfoil in the zone of non-interlinking, the spar portion extending outside the airfoil through the bottom edge of said airfoil. The enlarged portion extends from the spar portion outside the airfoil. The airfoil includes skins that are not interlinked with each other in the zone of non-interlinking and that surround the spar portion. The skins define two housings present inside the airfoil on respective sides of the spar portion and opening out through the bottom edge of the airfoil.

First claim

The invention claimed is:

1. A fiber-reinforcing structure for a propeller blade made of composite material, the fiber-reinforcing structure having an airfoil, a spar portion, and an enlarged portion, the fiber-reinforcing structure being continuously woven as a single piece by three-dimensionally weaving a fiber structure blank to entirely form the airfoil, the spar portion and the enlarged portion, the airfoil extending in a longitudinal direction between a bottom edge and a top edge and extending in a transverse direction between a front edge and a rear edge, the fiber-reinforcing structure including a zone of non-interlinking between the front and rear edges of the airfoil in the transverse direction, and extending between an intermediate zone and the bottom edge of said airfoil in the longitudinal direction, the spar portion extending inside the airfoil in the zone of non-interlinking, being set back from the front and rear edges of said airfoil in the transverse direction, the spar portion leading to the outside of the airfoil in the bottom edge of said airfoil, the enlarged portion extending from the spar portion outside the airfoil, the enlarged portion extending in the transverse direction over a length that is shorter than the length of the bottom edge of the airfoil, the airfoil having first and second skins in the zone of non-interlinking that are not interlinked with each other, the first and second skins extending between the front and rear edges of the airfoil in the transverse direction, and extending between the intermediate zone and the bottom edge of said airfoil in the longitudinal direction, the first and second skins surrounding the spar portion, the first and second skins defining first and second housings inside the airfoil, wherein the first and second housings are present on respective sides of the spar portion in the transverse direction, the first and second housings opening out through the bottom edge of the airfoil,
wherein an outline of the spar portion, of the bottom edge and of the enlarged portion is formed of yarns that are cut off in said three-dimensionally weaved fiber structure blank.

2. The fiber-reinforcing structure according to claim 1 , wherein the front edge and the rear edge present respective slots extending in the longitudinal direction between the intermediate zone and the bottom edge of the fiber-reinforcing structure.

3. A propeller blade comprising fiber reinforcement constituted by a fiber-reinforcing structure according to claim 1 and densified by a matrix, the propeller blade comprising said airfoil, said spar portion extending inside the airfoil, a tang extending outside the airfoil, a root extending outside the airfoil from the tang, a first shaper part present in the first housing provided inside the airfoil, and a second shaper part present in the second housing provided inside the airfoil.

4. The propeller blade according to claim 3 , wherein the tang connecting the root to the spar portion presents side edges that are straight and parallel to the longitudinal direction.

5. The propeller blade according to claim 3 , wherein the height of the zone of non-interlinking present in the fiber-reinforcing structure constituting the fiber reinforcement of the propeller blade lies in the range 10% to 50% of the total height of the airfoil in the longitudinal direction.

6. An aeroengine including a plurality of propeller blades according to claim 3 .

7. An aircraft including at least one aeroengine according to claim 6 .

8. The fiber-reinforcing structure according to claim 1 , wherein the intermediate zone defines an intermediate portion in the single piece from which both the spar and the first and second skins start extending, the intermediate portion being provided within the bottom half of the airfoil.

9. A method of fabricating a reinforcing-fiber structure for a propeller blade out of composite material, the method comprising:
three-dimensionally weaving a fiber structure blank as a single piece between a plurality of layers of weft yarns and a plurality of layers of warp yarns, the blank extending in a longitudinal direction between a bottom portion and a top portion and extending in a transverse direction between a front edge and a rear edge, the blank comprising an airfoil blank, a spar portion blank, and an enlarged portion blank, the method comprising, during weaving of the fiber structure blank, forming non-interlinking inside the airfoil blank, the non-interlinking extending between an intermediate zone and the bottom edge of the fiber structure blank in the longitudinal direction, and extending between the front and rear edges of the fiber structure blank in the transverse direction, the non-interlinking separating first and second portions present on either side of the spar portion blank so as to form first and second skin portion blanks that are not interlinked with each other, the first and second skin blanks extending between the front and rear edges of the fiber structure blank in the transverse direction, and extending between the intermediate zone and the bottom edge of the fiber structure blank in the longitudinal direction, the skin blanks surrounding the spar portion blank, the first and second skin blanks defining first and second housings inside the fiber structure blank, the housings being present on respective sides of the spar portion blank in the transverse direction, the first and second housings opening out through the bottom portion of the fiber structure blank, wherein the fiber-reinforcing structure is continuously woven as a single piece to entirely form the airfoil, the spar portion and the enlarged portion;
cutting off floated yarns present at the outside of the fiber structure blank so as to define the outline of the fiber-reinforcing structure; and
cutting off floated yarns present around the spar portion blank and around the enlarged portion blank and also floated yarns present at the bottom portion of the fiber structure blank so as to obtain a fiber-reinforcing structure comprising an airfoil having a bottom edge from which an enlarged portion extends from a spar portion outside the airfoil, the enlarged portion extending in the transverse direction over a length shorter than the length of the bottom edge of the airfoil.

10. A method of fabricating a propeller blade out of composite material, the method comprising:
making a fiber-reinforcing structure in accordance with the method of claim 9 ;
shaping the fiber-reinforcing structure by inserting first and second shaper parts respectively into the first and second housings present inside the airfoil of the fiber-reinforcing structure in order to obtain a propeller blade preform;
densifying the preform with a matrix; and
machining away excess lengths present on the densified preform in order to obtain a propeller blade having said airfoil, said spar portion extending inside the airfoil, a tang extending outside the airfoil, a root extending outside the airfoil from the tang, said first shaper part present in the first housing formed inside the airfoil, and said second shaper part present in the second housing formed inside the airfoil.

11. The method of fabricating a propeller blade out of composite material according to claim 10 , for fabricating a propeller blade out of composite material, wherein the tang connecting the root to the spar portion presents side edges that are straight and parallel to the longitudinal direction.

12. The method of fabricating a propeller blade out of composite material according to claim 10 , for fabricating a propeller blade, wherein the height of the zone of non-interlinking present in the fiber-reinforcing structur

Assignees

• Safran Aircraft Engines

Inventors

• Courtier Vivien Mickaël

Classifications

• B29L2031/08

  Blades for rotors, stators, fans, turbines or the like, e.g. screw propellers · CPC title

• F04D29/324

  Blades · CPC title

• B29D99/0025

  Producing blades or the like, e.g. blades for turbines, propellers, or wings · CPC title

• F01D5/16

  for counteracting blade vibration · CPC title

• B64C11/26 Primary

  Fabricated blades · CPC title