| 摘要 |
958,513. Respiratory appliances. ELECTRONIQUE MEDICALE S.E.R.D.A.L. Nov. 25, 1960 [Dec. 2, 1959], No. 40627/60. Heading A5T. A respiratory apparatus comprises two separate bellows 1, 2 mounted between a fixed bar 3 and a common movable plate 4, both bellows being connected, with suitable valve means, to the face mask S. One bellows 1 is connected to the mask by a flexible pipe 9 and has valves 5, 11 set in a direction to pass air into the mask, while bellows 2 is connected by a similar tube 10 and has valves 12, 6 permitting flow of air out from the mask to atmosphere. As the bellows are compressed, valve 5 is closed and air previously drawn into the bellows 1 is forced through valve 11 into the patient's lungs, while, at the same time, the air in bellows 2 is expelled to atmosphere through valve 6. On the subsequent expansion stroke of the bellows, valve 11 closes as fresh air is drawn into bellows 1 while, with valve 6 closed, bellows 2 draws air out from the patient's lungs through valve 12. Valves 11, 12 are set to open under extremely low pressure such as below 2 cm. W.G., but valves 5 and 6, respectively, are set to open at pressures of 7 cm. and 17 cm. W.G. With this arrangement it is impossible for the patient's lungs to be subject to a pressure greater than 17 cm. or to a vacuum greater than 7 cm. |
