Cushion Assembly

Abstract

A cushion assembly has first and second foam layers that are fixedly connected to each other so as to be contiguous. The cushion assembly also includes a fire-retardant covering and finds particular use as the seat base of a vehicle seat, especially an aircraft seat.

Claims

1. A cushion assembly for an aircraft seat comprising: a first foam layer; and a second foam layer; wherein the first foam layer is secured to the second foam layer to form a cushion element, the cushion assembly further including a fire-retardant material that extends around an outer surface of the cushion element.

2. A cushion assembly as claimed in claim 1, wherein the first foam layer is secured to the second foam layer by means of an adhesive.

3. A cushion assembly as claimed in claim 1, wherein the first foam layer has a higher compressive strength and/or a higher rigidity and/or is more lightweight than the second foam layer.

4. A cushion assembly as claimed in claim 1, wherein a molded density of the first foam layer is between 30 g/liter and 65 g/liter.

5. A cushion assembly as claimed in claim 1, wherein the first foam layer includes expanded polypropylene.

6. A cushion assembly as claimed in claim 1, wherein the second foam layer has a lower compressive strength and/or is less rigid and/or is less firm and/or is more shape adaptive than the first foam layer.

7. A cushion assembly as claimed in claim 1 wherein the second foam layer includes at least one of polyurethane, graphite filled polyurethane, or high resilience polyurethane.

8. A cushion assembly as claimed in claim 1, wherein the first foam layer underlies the second foam layer such that an upper surface of the first foam layer is secured to a lower surface of the second foam layer.

9. A cushion assembly as claimed in claim 1, wherein the first foam layer is substantially rigid.

10. A cushion assembly as claimed in claim 1, wherein a lower surface of the second foam layer is contiguous and/or conformal with an upper surface of the first foam layer.

11. A cushion assembly as claimed in claim 1, wherein the fire retardant material extends around an entire surface of the cushion element.

12. A cushion assembly as claimed in claim 1, further including a cover that extends around at least a part of an outer surface of the fire retardant material.

13. A cushion assembly as claimed in claim 1, wherein the first foam layer exhibits a greater firmness than the second foam layer.

14. A seat having a cushion assembly according to claim 1.

15. A vehicle, vessel, or aircraft having a seat as claimed in claim 14.

16. A cushion assembly for an aircraft seat comprising: a first foam layer; and a second foam layer; the first foam layer being secured to the second foam layer to form a cushion element, the cushion assembly further including a fire-retardant material that extends around the outer surface of the cushion element, wherein the first foam layer is substantially rigid and is secured to the second foam layer by means of an adhesive, and wherein a lower surface of the second foam layer is contiguous and/or conformal with an upper surface of the first foam layer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIG. 1 is a sectional elevational view showing a seat cushion assembly according to an exemplary embodiment of the present invention.

[0024] FIG. 2a is a perspective view showing a row of aircraft seats each including a cushion assembly according to another exemplary embodiment of the present invention.

[0025] FIG. 2b is a series of perspective views schematically showing the manner of assembly of one of the cushion assemblies shown in FIG. 2a.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0026] FIG. 1 shows a cushion assembly 10 according to an embodiment of the present invention. Although in this example the cushion assembly 10 forms a seat base, it will be appreciated that the cushion assembly 10 may form, e.g., the back of a seat.

[0027] The cushion assembly 10 shown in FIG. 1 includes a first foam layer 1 and a second foam layer 2. An upper surface of the first foam layer 1 is secured to a lower surface of the second foam layer 2 by means of an adhesive layer 3 to form a cushion element 4. The cushion element 4 is entirely covered in a fire-block fabric 5 that entirely wraps around the outer surface of the cushion element. A lightweight leather trim or cover 6 is also provided that extends around an upper surface of the cushion assembly 10 in normal use, as well as around side edges thereof, if desired.

[0028] The first foam layer is molded such the geometry of the first foam layer 1 and/or the resulting cushion assembly 10 varies. Specifically, it can be seen from FIG. 1, which shows a cross section through the cushion assembly 10, that the thickness of the cushion assembly 10 varies. Thus, the upper surface of the first foam layer 1 exhibits a sloping portion 7 such that the thickness of the first foam layer 1 varies from a first thickness t.sub.1 to a second thickness t.sub.2. The thicker section t.sub.2 of the cushion assembly 10 is intended to be located at or near the back of the seat in use, thereby providing a more ergonomic profile and greater degree of support to the lumber region of a user. Furthermore, the lower surface of the first foam layer 1 is also shaped so as to allow the cushion to be received on a pair of seat spars 8.

[0029] The first foam layer 1 is intended to provide support to a user in use and includes expanded polypropylene having inherent fire resistive properties, a molded density of around 55 g/liter, and a firmness of greater than 200 N. It will be appreciated that “support” refers to the ability of the foam to “push back” against weight and prevent the foam from changing shape. The second foam layer 2 includes combustion modified high resilience polyurethane having a molded density of 65 g/liter and a firmness of between 100 N and 400 N. It will be appreciated that “firmness” refers to a measurement of the surface feel of the foam and is a measure of the force expressed in Newtons required to compress a test piece to a specified percentage of its originally thickness. Both support and firmness affect the resulting comfort of the cushion, and it is advantageous for the properties of the two layers 1 and 2 to be selected to provide desired levels of both of these quantities.

[0030] FIG. 2a shows a row of aircraft seats 21 each including a cushion assembly 20 according to another example embodiment of the present invention. A schematic view of one of the cushion assemblies 20 is shown in FIG. 2b and includes a first foam layer 22 and a second foam layer 23. An upper surface of the first foam layer 22 is secured to a lower surface of the second foam layer 2 by means of an adhesive layer to form a cushion element. This cushion element is entirely covered in a fire-block fabric to form a fire-blocked cushion element 24. A lightweight leather trim or cover is also provided to the cushion assembly 25.

[0031] It should be noted that the above-mentioned embodiments illustrate, rather than limit, the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. The word “comprising” does not exclude the presence of elements or steps other than those listed in a claim, “a” or “an” does not exclude a plurality, and a single feature or other unit may fulfill the functions of several units recited in the claims. Any reference signs in the claims shall not be construed so as to limit their scope.

[0032] The principle and mode of operation of this invention have been explained and illustrated in its preferred embodiment. However, it must be understood that this invention may be practiced otherwise than as specifically explained and illustrated without departing from its spirit or scope.