Air service medical / War Department. Air Service. Division of Military Aeronautics.
- Date:
- 1919
Licence: Public Domain Mark
Credit: Air service medical / War Department. Air Service. Division of Military Aeronautics. Source: Wellcome Collection.
648/670 page 430
![Low-pressure L connections. Masks. ~ High-pressure tubing and its connections. Manifold connections. Tanks and valves. Permanent oxygen crates. All of this equipment is installed on the plane with exception of crates. There is considerable operating and maintenance equipment which is not used on the plane, such as pumps, refilling stations, large tanks, etc., which are necessary to maintain a constant supply of clean oxygen. The functioning of the oxygen equipment is to furnish the proper quantity of oxygen to fliers at all times and altitudes for the proper sustenance for maximum human efficiency. The oxygen is stored in the smal] tanks under a pressure of 2,250 pounds per square inch. This pressure is automatically reduced and the required amount auto- matically delivered by the apparatus. All equipment has been carefully designed for complete standardi- zation, continuity of operation, reliability, and maximum efficiency. The entire equipment is automatic. There are no exposed moving parts or elements. All the flier has to do is to turn on the oxygen at the tank and put on his oxygen mask. The apparatus automati- cally accomplishes the results. The apparatus now in production is known as the Dreyer type. It was adopted by our Air Service December 5, 1917. It is approxi- mately 6 by 5 by 2 inches high and weighs about 4 pounds. AIl work- ing parts are contained in a pressed steel case having the necessary openings for connections, gauges, etc. It consists of four elementary parts—the reducing valve, the control valve, aneroid valve, and flow indicator. Mounted on the reducing valve is a higher-pressure gauge, which shows the tank pressure and quantity of oxygen in the tanks. ‘The scale of this gauge is so arranged that when the oxygen is getting low the quantity will indicate so by appearing in a marked danger zone. The reducing valve is a delicate but simple device which automatically reduces the tank pressure from an aver- age of 50 pounds to 2,250 pounds to a final pressure of about 3 pounds gauge. This is accomplished automatically, and no adjustments are necessary. From the reducing valve the low-pressure oxygen is delivered t«, the control valve. This is a simple arrangement which controls the flow of oxygen for either one or two men. The handle of this valve extends through the case, is plainly marked, and easily handled. Before flying this valve is set so that the apparatus will deliver oxy- gen for the required number of persons.](https://iiif.wellcomecollection.org/image/b32171936_0648.jp2/full/800%2C/0/default.jpg)
