摘要 |
The multi-state support provides the use of pressurized fluid to cause expansion of an expandable volume positioned above a roller assembly which, in turn, places the support in either a rolling or non-rolling state. In a first embodiment, the roller assembly is fixed relative to a support surface. Expansion of the volume results in contact between a wall of the expandable volume and the rollers of the roller assembly. This contact prevents rotation of the rollers and defines the non-rolling state. In a second embodiment, the roller assembly is moveable relative to the support surface. Expansion of the volume results in the contact between a wall of the expandable volume and the roller support without interfering with the ability of the rollers to rotate relative to the roller support. Expansion of the volume causes the extension of the rollers of the roller assembly from within the sole. The extension of the rollers from the sole defines the rolling state.
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