GB1158865A - Respiratory Gas Regulator Assembly particularly for Oxygen Distribution Apparatus for supplying Masks worn by Aircraft Crew Members - Google Patents

Abstract

1,158,865. Respiratory apparatus. SOC. D'lNSTRUMENTS DE MESURE. 9 Sept., 1966 [9 Sept., 1965], No. 40449/66. Heading A5T. Respiratory apparatus for controlling the supply of gas from a source connected to an inlet 8 to a mask communicating with first and second outlets 5, 40, includes a main demand valve 26 operated by a respirationresponsive diaphragm 31 in normal use of the apparatus, an emergency demand valve 26a operated by a second respiration-responsive diaphragm 31a and arranged in parallel with the main demand valve 26, a push-buttonoperated changeover valve device for rendering one of the demand valves operative for supplying gas to the first outlet 5 and the other inoperative and an automatic changeover valve 34 arranged to supply the second outlet 40 from the control chamber of the operative demand. The diaphragms 31, 31a are exposed to pressures in the respiratory circuit through a duct 2 communicating with the outlet 1 and gas flowing through either of the demand valves 26, 26a flows to the outlet via a nozzle 5. In normal use of the device, the position of changeover valves 19, 21, as determined by the push-button 24 is such that gas from the source flows to a chamber 54 so that a diaphragm 15 opens a valve 10 upstream of the main demand valve 26 and closes a valve 11 upstream of the emergency demand valve 26a. Gas is then supplied through the main demand valve 26 and to the control chamber 30 of its controlling diaphragm 31. In emergency, the valves 19, 21 are changed over by the push-button 24 to vent the chamber 54 to atmosphere so that the diaphragm 15 closes the valve 10 and opens the valve 11. Gas is then supplied through the emergency demand valve 26a and to the control chamber 30a of its controlling diaphragm 31a Gas flowing to either of the control chambers 30, 30a is returned to the respiratory circuit via conduits 39, 40 and a valve 34 which is appropriately changed over, when the changeover valves 19, 21 are operated, by changes in pressure in a conduit 35 connected with the emergency gas supply conduits. Valves 42, 44, 45, 50 and 50a are provided to control the admission of external air in accordance with altitude and permit the entry of external air if respiratory gas does not reach the outlet 1.