| 摘要 |
<p>A ventilator to replace or supplement a patient's breathing includes a control valve in the form of a proportional obstacle valve (POV) (20) to provide improved air flow control and ventilator operation reliability. The POV includes an inlet, an outlet and a bypass. A stopcock controlled by a stepper motor directs the flow of air through the bypass and outlet permitting the turbine (18) to operate a constant RPM yet allowing control of the airflow to a patient. The ventilator also includes inhalation and exhalation valve assemblies (26, 30) which improve air flow control and are easy to manufacture. The inhalation valve includes an orifice disk to allow pressure sensors to move accurately measure air flow. The exhalation valve assembly includes wings to reduce turbulence and enhance sensor accuracy. The exhalation valve assembly is arranged to have warm air from cooling the turbine blow over the assembly to reduce the possibility of condensation forming therein. The ventilator also includes an improved power supply with redundant sources of power.</p> |
