Respirating apparatus for patients

Claim 1

An anesthesia respirating apparatus for patients comprising a closed line system that is provided with a first pump by means of which respiratory gas may be circulated in said closed line system and with a second pump by means of which the respiratory gas in said closed line system may be alternately compressed and decompressed to make the patient respire in accordance with a certain respiratory pattern, the closed line system being provided with means for connecting said closed line system with the patient and with further connecting means for supplying the various components of the respiratory gas to said closed line system and with still further means for withdrawing carbon dioxide that has been exhaled by the patient into the closed line system, the second pump including a plurality of simultaneously operable pump chambers connected in parallel with one another, each pump chamber having a flexible membrane which extends completely across said chamber and which separates said chamber into a primary and a secondary portion, the secondary portion of each pump chamber being connected to the closed line system and the primary portion of each pump chamber being connected to a supply of compressed air whose pressure may be varied to effect a pumping action of the membrane, and a plurality of externally controllable valves located respectively between said compressed air supply and the primary portions of said pump chambers and between the secondary portions of said pump chambers and said closed line system for selectively varying the number of said parallel pump chambers that are simultaneously operative to effect a pumping action at any given time thereby to control the pressure of the respiratory gas being circulated in said closed line system.