| 摘要 |
864,044. Respiratory appliances. AIRSHIELDS Inc. Aug. 14, 1959 [Aug. 21, 1958], No. 27842/59. Class 81 (2). Respiratory apparatus has means for measuring the volume of air inhaled and exhaled at each respiration. The mask 5 is supplied from cylinders 10a, 10b through a pipe 9 and this is connected with the interior of a bellows 13, so that the latter expands and contracts with the patient's respiration. The bellows is enclosed in a chamber 12 having transparent walls and the intervening space is connected through a pipe 20 to a flexible bag 19. Movement of the bellows can thus be observed through the wall of the chamber 12 and measured against a scale 30, while displaced air causes distension or collapse of the bag 19. Provision of the bag 19 enables the operator to control inhalation by manual pressure on it. If the system receives an excessive volume of gas from the supply cylinders the increased extension of the bellows ultimately lifts a valve 22 by means of a cord 26 to vent the system to atmosphere. |
