| 摘要 |
A patient demand valve is automatically cycled open to provide selected volumes of oxygen at selected intervals. A pneumatic controller connected to an oxygen supply provides a control pressure to operate the demand valve, with the cycling provided by pneumatic timers. The oxygen supply to the patient is also through the controller to the demand valve. A tidal volume flow control valve provides an adjustable flow rate when open. In one embodiment, the patient demand valve is in an assembly which includes a safety subassembly, which incorporates a signaling device that indicates an over-pressure condition in the assembly as a result of a blockage of gas flow to the patient, and also includes an anti-suffocation valve. |
