Patent ID: 7979930

Claim:
A yieldable support structure for a furniture item, comprising: a movable mattress mounted on the furniture item for movement between a storage position and a body-supporting use position, the mattress including a spring assembly having an upper wire grid, a lower wire grid, and a system of springs pivotably connected to the grids for movement from a compact position in which the grids are adjacent one another when the mattress is in the storage position, to an upright position in which the grids are resiliently held and spaced apart by the springs when the mattress is in the use position; a stationary support; a stationary lower support element mounted on the stationary support and immovable in both the storage and use positions of the mattress, the lower support element extending along a transverse direction and pivotably connected to the lower wire grid; a movable upper support element located above, and spaced away from, the lower support element along an upright direction perpendicular to the transverse direction, the upper support element extending in mutual parallelism with the lower support element along the transverse direction and pivotably connected to the upper wire grid; and yieldable elements between the support elements and operative for constantly urging the upper support element away from the lower support element along the upright direction, and for supporting the upper support element for yielding movement along the upright direction while maintaining said mutual parallelism with the lower support element when the upper support element is subjected to a compressive load in the use position.