摘要 |
The sleep unit includes a base upon which is mounted a single set of springs. These springs are overlaid with cushion material. The springs are leaf-type springs having a curved configuration. The spring action is such that the resistance to deflection increases with increased load. Thus, the sleep unit has an initial softness followed by increased firmness depending upon the weight of the user. Means are provided to permit pre-compression of the springs to vary the initial firmness of the sleep unit.
|