| 摘要 |
A sealable, composite cushion is disclosed having a plurality of resilient support member horizontally disposed to one another and surrounded by a fluid impervious membrane. Each resilient support member has a known Indentation Force Deflection (IFD) value and is located in the cushion based upon medical criteria to provide zones of varying support. In an embodiment, the resilient members are bonded to the membrane and act as tension members to maintain the cushion's form while under a load. As a result, the cushion resists further deflection not only by the resilient members' resistance to compression, but also by an increased internal pressure. Accordingly, the cushion of the present invention is a composite of fluid flotation and compression resistance. A valve may be incorporated into the cushion to regulate the fluid floatation characteristics of the cushion or to assist in its transportation. In another embodiment, the resilient support members are not bonded to an upper membrane portion, thereby decreasing shear forces acting upon the resilient members when the cushion is under load. Further, excess membrane may be located at the cushion periphery. When subject to a load, this excess membrane material can migrate to the upper portion of the cushion, thereby decreasing undesirable peripheral distortion of the cushion.
|
