| 摘要 |
An anaesthetic vaporiser 1 includes an inlet 2 for carrier gas, an outlet 4 for carrier gas and anaesthetic agent, a first passage 6 interconnecting the inlet to the outlet and a first fixed flow restrictor 8 located in the passage 6. A second passage 56 extends between a vaporising chamber and the outlet 4 and located therein is a second fixed flow restrictor 54 and also a solenoid valve 58. A first pressure transducer 50 generates an electrical signal corresponding to the pressure differential P1 across the restrictor 8; and a second pressure transducer 52 generates an electrical signal corresponding to the pressure differential P2 between the passages 6, 56. A controller responsive to said electrical signals from the pressure transducers 50, 52 transmits an electrical signal to the valve 58 for controlling the flow of gaseous anaesthetic agent through the passage 56 such that P2 = P1 x constant. |
