| 摘要 |
A pulmonary ventilator system has a bellows assembly and a source of driving gas connected by a series branch including an electrically-controlled switching valve and a motor-controlled flow-rate-controlling valve. A controller including a microprocessor senses the position of the flow-rate-controlling valve via a mechanical to electrical transducer and has outputs connected to and controlling the switching valve and the motor. It has programmed in its memory the maximum flow rate capacity of the flow-rate-controlling valve and the maximum capacity of the bellows. The microprocessor is capable of receiving from an operator his target values for minute volume, breathing rate and expiration time to inspiration time ratio. When the combination of these target values predict a flow rate or a tidal volume greater than the capacity of the flow-controlling valve and or greater than the bellows can handle, it reinstructs the ventilator system to employ a new and realizable value of breathing rate and/or expiration time to inspiration time ratio. The actual operating parameters realized by the controller are displayed. |
