Composite rotor blade having weighted material for mass balancing
A rotor blade for an aircraft includes a composite portion having fiber-reinforced resin material, the composite portion having an outside surface that forms at least a partial airfoil shape. The weighted portion includes a plurality of weighted material layers and a plurality of fiber-reinforced resin material layers. Weighted material is configured to be compatible with and integrated into composite manufacturing processes used to fabricate the rotor blade. The weighted portion has a higher density than the composite portion and positioned to produce desired mass balance characteristics of the rotor blade.
1. A rotor blade for an aircraft, the rotor blade comprising:
a composite portion having fiber-reinforced resin material, the composite portion having an outside surface that forms at least a partial airfoil shape;
a weighted portion comprising:
a plurality of weighted material layers;
a plurality of fiber-reinforced resin material layers;
wherein the each weighted material layer is adjacent with at least one fiber-reinforced resin material layer;
wherein the each weighted material layer is cross-linked with the adjacent fiber-reinforced resin material layer thereby retaining the each weighted material layer;
wherein a thickness of each of the plurality of composite layers is equal to a thickness of each of the plurality of weighted layers; and
wherein the weighted portion has a higher density than the composite portion.
2. The rotor blade according to claim 1 , wherein the weighted portion is located near a leading edge portion of the rotor blade.
3. The rotor blade according to claim 1 , wherein each layer of weighted material is a thin strip of metal.
4. The rotor blade according to claim 3 , wherein the metal is lead.
5. The rotor blade according to claim 3 , wherein the metal is tungsten.
6. The rotor blade according to claim 1 , wherein each weighted material layer comprises:
a plurality of strips of dense metal woven together with a plurality of strips of fiber composite material.
7. The rotor blade according to claim 6 , wherein the plurality of strips of dense metal woven together are wider than the plurality of strips of fiber composite material.
8. The rotor blade according to claim 1 , wherein each weighted material layer comprises:
a plurality of strands of dense metal.
9. The rotor blade according to claim 1 , the weighted portion further comprising:
an adhesive layer located between each weighted material layer and each fiber-reinforced resin material layer.
10. The rotor blade according to claim 1 , wherein the composite portion and the weighted portion are at least partially dovetailed together at an area of abutment.
11. A composite member comprising:
a composite portion having fiber-reinforced resin material;
a weighted portion located within the composite portion, the weighted portion having a higher density than the composite portion so that a center of gravity of the composite member is skewed toward the location of the weighted portion, the weighted portion comprising:
a plurality of composite layers; and
a plurality of weighted layers, wherein each weighted layer and composite layer are located in alternating form;
wherein the each weighted layer is cross-linked with the adjacent composite layer; and
wherein a thickness of each of the plurality of composite layers is equal to a thickness of each of the plurality of weighted layers.
12. The composite member according to claim 11 , each weighted layer comprising:
a weighted weave including a fiber composite material woven together with a plurality of strips of a dense metal.
13. The composite member according to claim 11 , each weighted layer comprising:
a weighted weave including a fiber composite material woven together with a plurality of strands of dense metal; and
wherein the strands of dense metal are captured by being woven together with the fiber composite material.
14. The composite member according to claim 11 , the weighted portion further comprising:
a dense metal powder integrated with the composite layers.
15. A method of making a weighted portion of a rotor blade, comprising:
laying up alternating layers of weighted material and layers of fiber/resin composite material;
cross-linking each layer of weighted material with the adjacent layer of composite material;
trapping the weighted material between the layers of composite material; and
applying heat so as to cure the weighted portion;
wherein a thickness of each of the layers of weighted material is equal to a thickness of each of the layers of fiber/resin composite material.
16. The method according to claim 15 , wherein the laying up alternating layers of weighted material and layers of fiber/resin composite material is accomplished, at least in part, by an automated fiber placement process.
17. The method according to claim 15 , wherein the laying up alternating layers of weighted material and layers of fiber/resin composite material is accomplished, at least in part, by a manual fiber placement process.
18. The method according to claim 15 , wherein the laying up of weighted material is accomplished by a manual fiber placement process, while the laying up of layers of fiber/resin composite material is accomplished by an automated fiber placement process.
19. The method according to claim 15 , wherein the weighted material includes thin strips of a dense metal.