| 摘要 |
650,214. Anaesthetic apparatus. SIEBE, GORMAN & CO., Ltd., DAVIS, Sir R. H., and DAVIS, R. W. G. Dec. 16, 1948, No. 32628. [Class 81(ii)] Analgesia apparatus employing evaporable liquid has a temperature control of the mixture strength either in the air supply to the liquid or in an air supply byepassing the liquid or both. As applied to apparatus of the general type described in Specification 604,558 and in which air passed into a liquid container 1 through orifices 27, outwards through orifices 25 in a cylinder 24 and upwards through holes 21 to a central tube 19, the air which has thus been in contact with the liquid is mixed with air entering directly through a casing 18 before passing through a non- return valve 8 to the tube 6 leading to the mouthpiece. The path of the diluting air is partially obstructed by a valve disc 13 set in a tapered orifice 14 and movable longitudinally by a temperature-sensitive bellows 9 filled with volatile liquid. As the temperature rises the bellows expands and opens the valve, so admitting a larger proportion of air. Alternatively the control may be in the path of air passing over the anaesthetic or both paths may be controlled simultaneously. In the device shown, the liquid container 1 is provided internally with a cylindrical wick 28 so that the area from which evaporation can take place remains substantially constant if the container is tilted. |
