| 摘要 |
An improved patient support structure comprises an articulatable frame, a plurality of elongated inflatable sacks, and an air blower connected to the sacks which rests atop a neoprene membrane. A variable autotransformer powers the air blower and is controlled by an electronic circuit which balances the autotransformer voltage against a voltage output from a preset variable resistor. A multi-outlet, variable flow, gas valve comprises a housing defining an inlet, an outlet, and a passageway. The valve housing further defines at least two cylinder chambers communicating with the passageway. A piston is non-rotatably disposed inside each cylinder chamber and has a threaded opening through the centre which receives a threaded portion of a rotatable shaft. One end of the shaft is rotated by a motor, and the other end is connected to a potentiometer. A valve control circuit chooses between preset variable resistors based upon a signal from camactuatable switches connected to one of the articulatable sections of the frame. The sacks can be rapidly deflated via solenoid valves, and the pipes from the blower can be directed alternatively to different sacks by manually operated valves. Pressure sensitive switches indicate when a substantially deflated condition exists in one or more of the sacks. Fabric panels are attached via snap members to the ends of the sacks and the frame. |
