Energy absorbing brackets for passenger seats

1. A seat assembly, comprising:

a frame;

a set of spreader brackets attached to the frame, each spreader bracket comprising:

a first component formed from a composite material;

a structural fill material; and

a second component formed from the composite material, the second component configured to couple with the first component to form a coupled structure, the structural fill material extending within a cavity of the coupled structure; and

a set of seat brackets attached to the set of spreader brackets, each seat bracket comprising:

a frangible structure formed from a plurality of layers of the composite material, wherein, in a particular layer orientation, the plurality of layers is arranged such that:

first layers of the plurality of layers are discontinuous throughout a shear area of the frangible structure; and

second layers of the plurality of layers are continuous throughout the shear area of the frangible structure, the frangible structure configured to break at or near the shear area in response to a load applied to a seatback.

2. The seat assembly of claim 1 , further comprising:

a seat pan disposed between lower portions of the set of spreader brackets; and

the seatback disposed between upper portions of the set of spreader brackets and attached to the set of spreader brackets.

3. The seat assembly of claim 2 , wherein each seat bracket further comprising:

a lower portion attached to the seat pan;

an upper portion attached to the seatback at a first location and at least one spreader bracket; and

a middle portion corresponding to the frangible structure that is attached to the seatback at a second location.

4. The seat assembly of claim 1 , wherein each of the first component and the second component comprises:

a first flange;

a second flange; and

a web extending between the first flange and the second flange.

5. An assembly, comprising: a spreader bracket comprising:

a first hollow component formed from a composite material; a fill material; and

a second hollow component formed from the composite material, the second hollow component being configured to couple with the first hollow component to form a coupled structure, the fill material extending within a cavity of the coupled structure, the coupled structure comprising:

a first leg extending in a first direction and including one or more upper mounting locations; and

a second leg extending in a second direction and including one or more lower mounting locations disposed along a bottom portion of the second leg.

6. The assembly of claim 5 , wherein the one or more upper mounting locations comprise a seatbelt anchor extending within the cavity of the coupled structure from a first exterior surface on a first web of the first hollow component to a second exterior surface on a second web of the second hollow component.

7. The assembly of claim 6 , wherein the coupled structure further comprises:

a first reinforcing zone comprising first one or more layers of the composite material disposed on the first web and extending between the seatbelt anchor and a first front flange of the first hollow component; and

a second reinforcing zone comprising second one or more layers of the composite material disposed on the second web and extending between the seatbelt anchor and a second front flange of the second hollow component.

8. The assembly of claim 7 , wherein the first one or more layers of the first reinforcing zone and the second one or more layers of the second reinforcing zone are selected such that, in a crash event, the seatbelt anchor moves toward the first front flange and the second front flange by crushing a portion of the fill material, a portion of the first reinforcing zone, and a portion of the second reinforcing zone.

9. The assembly of claim 5 , wherein the one or more mounting locations comprise one or more tubular rings extending through the cavity of the coupled structure from a first exterior surface on a first web of the first hollow component to a second exterior surface on a second web of the second hollow component.

10. The assembly of claim 5 , wherein the fill material comprises an energy absorbing foam material having a density of about 10 pounds per cubic foot.

11. The assembly of claim 5 , wherein the composite material comprises a thermoplastic structural composite or a thermoset structural composite.

12. The assembly of claim 5 , wherein each hollow component of the first hollow component and the second hollow component comprises:

a first flange;

a second flange; and

a web extending between the first flange and the second flange, at least one of the first flange or the second flange having a flange thickness that is greater than a web thickness of the web.

13. The assembly of claim 5 , wherein, in the coupled structure, an interior surface of the first hollow component contacts an exterior surface of the second hollow component.

14. The assembly of claim 5 , wherein, in the coupled structure the first hollow component comprises one or more darts disposed between the first leg and the second leg.

15. The assembly of claim 5 , further comprising: a seat bracket comprising:

an attachment location at which the seat bracket is attached to the spreader bracket; and

a frangible portion disposed below the attachment location and formed from a plurality of layers of the composite material, wherein, in a particular layer orientation, the plurality of layers are arranged such that:

first layers of the plurality of layers are discontinuous throughout a shear area of the frangible portion; and

second layers of the plurality of layers are continuous throughout the shear area of the frangible portion, the frangible portion configured to break at or about the shear area in response to a load applied to a seatback.

16. The assembly of claim 15 , wherein the shear area is a first shear area, and wherein the plurality of layers are further arranged such that:

the first layers of the plurality of layers are discontinuous throughout a second shear area of the frangible portion; and

the second layers of the plurality of layers are continuous throughout the second shear area of the frangible portion, the frangible portion configured to break at or about the first shear area and the second shear area in response to the force applied to the seatback.

17. An assembly, comprising:

a seat bracket comprising:

an upper portion comprising a first attachment location;

a lower portion comprising a second attachment location; and

a frangible portion disposed between the upper portion and the lower portion and formed from a plurality of layers of composite material, wherein, in a particular layer orientation, the plurality of layers are arranged such that:

first layers of the plurality of layers are discontinuous throughout a shear area of the frangible portion; and

second layers of the plurality of layers are continuous throughout the shear area of the frangible portion, the frangible portion being configured to break at the shear area when a predefined load is applied to the assembly.

18. The assembly of claim 17 , wherein the shear area is a first shear area, and wherein the plurality of layers are further arranged such that:

the first layers of the plurality of layers are discontinuous throughout a second shear area of the frangible portion; and

the second layers of the plurality of layers are continuous throughout the second shear area of the frangible portion, the frangible portion configured to break at or about the first shear area and the second shear area in response to the predefined load applied to the assembly.

19. The assembly of claim 18 , wherein the plurality of layers are further arranged such that third layers of the plurality of layers are continuous throughout the first shear area and the second shear area.

20. The assembly of claim 17 , wherein the particular layer orientation is a dominant layer orientation, the plurality of layers of composite material comprising other layers arranged in at least one other orientation comprising an orthogonal layer orientation that is orthogonal to the dominant layer orientation or a transverse orientation that is transverse to the dominant layer orientation.

21. The assembly of claim 17 , further comprising a spreader bracket attached to the seat bracket at the first attachment location, the spreader bracket comprising:

a first component formed from the composite material; a fill material; and

a second component formed from the composite material, the second component configured to couple with the first component to form a coupled structure, the fill material extending within a cavity of the coupled structure.

22. The assembly of claim 21 , wherein the frangible portion comprises a third attachment location, the assembly further comprising:

a seat pan attached to the seat bracket at the second attachment location; and

a seatback attached to the seat bracket at the third attachment location and the first attachment location.

23. The assembly of claim 22 , wherein the coupled structure further comprises:

a first leg extending in a first direction, the first leg comprising a seatbelt anchor extending within the cavity of the coupled structure from a first exterior surface of a first web of the first component to a second exterior surface of a second web of the second component; and

a second leg extending in a second direction, the second direction separated from the first direction by a first angle.

24. The assembly of claim 23 , wherein, during a crash event:

the frangible portion is configured such that application of the predefined load to an aft surface of the seatback causes the frangible portion to break at the shear area and an upper portion of the seatback to pivot about the first attachment location in a forward direction; and

the seatbelt anchor is configured such that the seatbelt anchor moves through the cavity of the coupled structure towards a first flange of the first component and a second flange of the second component located on a forward side of the coupled structure; and

the coupled structure is configured such that the first leg rotates relative to the second leg to form a second angle that is less than the first angle.