Patent attributes
A distortion generating sheet (22) intervenes between a first and a second flexible sheets (11) and (12), respectively, with one end (23) thereof fixed to the first sheet (11), and the other end (24) fixed to the second sheet (12). As a consequence, when a shear takes place across the first and second sheets (11) and (12), respectively, the shear is conveyed to the distortion generating sheet (22). A strain gauge (21) fixed to the distortion generating sheet (22) detects and measures the distortion generated by the shear in the distortion generating sheets (22). A third sheet (15) is further provided with its periphery bonded to the first sheet (11) to form a closed space. The force bearing the patient is measured by measuring the pressure in the space formed.
