| 摘要 |
A water mattress bag (l) made of a suitable water-tight resilient and tensile material intended for use together with a main mattress member (3) of a resilient, flexible foamed plastic or another similar material, which is provided with a recess (4) in its upper face which extends over a substantial portion of the length (L) and width (B) of said mattress surface. The bottom (la) of said water mattress bag (l) is shaped with a bulge (la') for cooperation with recess (4), and the top (ld) of water mattress bag (l) has a length and width approximately equal to the length (L) and width (B) of main mattress member (3). Water mattress (l0) comprises the above mentioned components, a flexible weight-distributing sheet shaped complementary with the opening of recess (4) on top of water mattress bag (l) and a mattress cover (l6). Water mattress bag (l) is partly filled and extends outwards to the lateral edges (3a) of main mattress member (3) and, thus, covers the flat edges (3b) around recess (4). Having a thickness (a), the top of weight distributing sheet (15), in a preferred embodiment, is caused to project higher than siad flat edges (3b) in an unloaded state. Mattress cover (l6) is stretched around main mattress member (3) with said components (l,l5) to keep them in place, providing a bias/increase of pressure of the water in water mattress bag (l) in an un-loaded state of said water mattress (l0). |
