| 摘要 |
783,180. Respiratory appliances. DRAGER, O. H. March 31, 1954 [April 4, 19531, No. 9503/54. Class 81 (2). Artificial respiration apparatus for use during anµsthesia, comprises a closed respiration air system including a respiration bag enclosed in a sealed chamber in which positive and negative pressures are alternately produced. The respiration bag 10 is connected in a closed respiration circuit by a connecting pipe 6 which branches into tubes 3 and 7, one 3 of which contains an exhalation non-return valve 4 and a carbon dioxide absorption cannister 5 and the other 7 being provided with an inhalation non-return valve 8 and connected with a pipe 9 through which anµsthetic is supplied to the apparatus. The tubes 3 and 7 are connected with a tube 2 which communicates with the patient by an intratracheal catheter. An additional respiration bag 31 is connected to the connecting pipe 6 by way of a valve 30 and is provided for the withdrawal of excess anµsthetic gas or the supply of additional anµsthetic gas as required. The respiration bag 10 is contained in a chamber 11 connected with a pump 15 which causes the air pressure within the chamber 11 to alternately rise and fall so that the resultant collapse and expansion of the respiration bag 10 brings about artificial respiration. Air is withdrawn from a pump chamber 20 connected with the chamber 11 by an injector 16 through a valve 18, 21 on the suction side of the injector 16, an adjustable excess pressure valve 27 on the pressure side of the injector 16 being open and an adjustable suction valve 29 on the suction side of the injector 16 being closed. When the pressure in the pump chamber 20 has reached a preset minimum, a diaphragm 26 in the wall of the pump chamber 20 moves inwardly to close the valve 18, 21 and open another valve 19, 22 which is on the pressure side of the injector 16 and connected to the first valve 18, 21 by a lever 23. Air passes into the chamber 20, the excess pressure valve 27 closes and the suction valve 29 opens. When the pressure in the pump chamber 20 has reached a preset maximum, the diaphragm 26 moves outwardly so that the valves are reversed and air is again withdrawn. The maximum volume of the respiration bag 10 is adjustable by arranging either a displaceable piston 12 or an inflatable bag (not shown) in the chamber 11 so that it limits the expansion of the respiration bag 10. Alternatively the respiration bag 10 may be exchanged with others of different volumes. The diaphragm 26, the suction valve 29 and the excess pressure valve 27 may be adjusted to respond at different pressures so that the maximum and minimum pressures in the chamber 11 and the time of rise and fall of pressure may be adjusted. Specifications 625,284 and 649,229 are referred to. |
