Method of fabricating a spar for a blade, and a method of fabricating a blade

Patent metadata

Field	Value
Publication number	US-9950478-B2
Application number	US-201514800965-A
Country	US
Kind code	B2
Filing date	Jul 16, 2015
Priority date	Jul 18, 2014
Publication date	Apr 24, 2018
Grant date	Apr 24, 2018

Abstract

A method of fabricating a spar for a blade, which spar includes transversely at least one arrangement. A male former is defined for each arrangement that is to be fabricated and each arrangement is subdivided into a pressure-side subassembly and a suction-side subassembly, each comprising a plurality of hanks, each hank comprising a plurality of U-shaped tape segments stacked on one another. Each subassembly of an arrangement is fabricated outside a mold for fabricating the blade on a single former adapted to that particular arrangement, fabrication being by stacking tape segments on the former using a fiber placement method implemented by a placement head.

First claim

What is claimed is:

1. A method of fabricating a spar of a blade from tapes made of composite materials, the spar including transversely at least one arrangement, each arrangement being for winding around a root axis of the spar, the method comprising the following steps:
during a preparation step, defining one male former per arrangement to be fabricated, each former having a pressure-side running surface, and a suction-side running surface of U-shape, each running surface comprising:
a root zone provided with a C-shaped root wall forming an end wall of the U-shape suction-side running surface;
a connection zone presenting two twisted connection walls that are connected respectively to two ends of the end wall; and
a running zone presenting two running walls connected respectively to the two connection walls;

during a fabrication step, subdividing each arrangement into a pressure-side subassembly and a suction-side subassembly, each comprising at least one hank, each hank comprising a plurality of U-shaped tape segments stacked on one another;
during the fabrication step, fabricating the pressure-side subassembly and the suction-side subassembly of an arrangement on a single former adapted to the arrangement and outside a mold for fabricating the blade, the pressure-side subassembly and the suction-side subassembly of an arrangement being fabricated by stacking tape segments on the former by a fiber placement method using a placement head, the placement head winding each tape segment of the pressure-side subassembly around a root axis by laying the segment over the pressure-side running surface, the placement head winding each tape segment of the suction-side subassembly around a root axis by laying the segment on the suction-side running surface; and
during a heating step, heating each arrangement on its former.

2. The method according to claim 1 , wherein at least one former is a removable former formed using tooling representing an inside volume of a spar, the former being removed after the heating step.

3. The method according to claim 1 , wherein at least one former is a non-removable former formed by a fastener bushing, a root wedge surrounding the fastener bushing, and a filler material of a blade.

4. The method according to claim 1 , wherein the former is arranged on tooling that is secured to a rocker, the rocker rocking the former during the fabrication step.

5. The method according to claim 1 , wherein during the fabrication step, the hanks are formed one after another by laying all of the segments of one of the hanks on a former before laying the segments of another hank.

6. The method according to claim 1 , wherein at least one tape segment of a subassembly covers, in the running zone, another segment of the subassembly over a chord width that decreases.

7. The method according to claim 1 , wherein at least one tape segment of a subassembly extends spanwise from the root axis over a length referred to as a “first” length, and at least one other segment extends spanwise from the root axis over a length referred to as a “second” length that is different from the first length so as to impart decreasing thickness to the subassembly.

8. The method according to claim 1 , wherein the spar includes an arrangement referred to as a “trailing-edge” arrangement, and a “trailing-edge” former is defined that is provided with a pressure-side running surface and with a suction-side running surface that are vertically spaced apart from each other.

9. The method according to claim 1 , wherein the spar has a “leading-edge” arrangement and a “leading-edge” former is defined having a pressure-side running surface and a suction-side running surface that join together to form a tip.

10. The method according to claim 9 , wherein the leading-edge former presents:
a suction-side running surface provided transversely with an outer suction-side zone and an inner suction-side zone that are spaced apart vertically by a suction-side step; and
a pressure-side running surface that is provided transversely with an outer pressure-side zone and with an inner pressure-side zone that are spaced apart vertically by a pressure-side step, the inner pressure-side zone and the inner suction-side zone joining together to form the tip.

11. The method according to claim 10 , wherein the laying of segments of a hank of the pressure-side subassembly is alternated with the laying of segments of a hank of the suction-side subassembly with a strand of one hank being placed adjacent against a strand of the previously-laid hank in the region of the tip in order to form a herring-bone configuration at the leading-edge.

12. The method according to claim 10 , wherein during the fabrication step the following steps are performed:
forming a first hank of the suction-side subassembly by organizing a plurality of segments on the former using the placement head, each segment of the first hank comprising in succession a first strand with a central strand and a second strand, the first strand being laid on the outer suction-side zone and a suction-side connection zone, the central strand being laid on a suction-side root zone, and the second strand being laid on the suction-side connection zone and the inner suction-side zone, a suction-side portion of the outer suction-side zone leading to the suction-side step not being covered by the first strand, the second strand projecting transversely from the inner suction-side zone;
forming a second hank of the pressure-side subassembly by organizing a plurality of segments on the former using the placement head, each segment of the second hank comprising in succession a third strand with a central strand and a fourth strand, the third strand being laid on the outer pressure-side zone and on a pressure-side connection zone, the central strand being laid on a pressure-side root zone, the fourth strand being laid on the pressure-side connection zone and on the inner pressure-side zone, a pressure-side portion of the outer pressure-side zone leading to a pressure-side step not being covered by the first strand, the fourth strand projecting transversely from the inner pressure-side in order to press against an edge of the first strand;
forming a third hank of the suction-side subassembly by organizing a plurality of segments on the former using the placement head, each segment of the third hank comprising in succession a fifth strand with a central strand and a sixth strand, the fifth strand being laid jointly on the suction-side portion and partially on the second strand in the running portion and then covering the suction-side connection zone in the running portion, the central strand being laid on the suction-side root zone, and the sixth strand being laid on the suction-side connection zone and then in the running zone on the second strand and on an edge of the fourth strand, the sixth strand projecting transversely from the fourth strand; and
forming a fourth hank of the pressure-side subassembly by organizing a plurality of segments on the former using the placement head, each segment of the fourth hank comprising in succession a seventh strand with a central strand and an eighth strand, the seventh strand being laid jointly on the pressure-side portion and in part on the fourth strand in the running portion and then covering the pressure-side connection zone in the running portion, the central strand being laid on the pressure-side root zone, and the eighth strand being laid on the pressure-side connection zone and then in the running zone on the fourth strand and against an edge of the sixth strand.

13. The method according to claim 12 , wherein the portion of

Assignees

• Airbus Helicopters

Inventors

• Gaffiero Jacques
• Rinaldi Benedicte
• Amari Andre

Classifications

• B33Y80/00

  Products made by additive manufacturing · CPC title

• F01D5/147

  Construction, i.e. structural features, e.g. of weight-saving hollow blades (F01D5/148, F01D5/16 and F01D5/20 take precedence; blade shape F01D5/141; blades with cooling or heating channels or cavities F01D5/18; heating, heat-insulating or cooling means on blades F01D5/18) · CPC title

• B29D99/0025

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

• B29C70/382

  Automated fiber placement [AFP] · CPC title

• B29K2105/0872

  Prepregs · CPC title