Patent GB-841778-A (GB)
Title: Control apparatus for the air and oxygen supply to the suits of aircraft personnel
Inventor: MEJEAN JACQUES G
IPC: A62B9/02
Filed: 1957-09-13
Abstract: 841,778. Flying suit pressure regulators. AEROTEC CORPORATION. Sept. 13, 1957, No. 28938/57. Class 68(2). A control apparatus for regulating the flow of air and oxygen to a flying suit and helmet carries an emergency oxygen supply which supplies both the helmet and the suit in the event of failure of the supply from the aircraft. A system of valves is provided which relate the pressure of the suit - inflating air and the helmet oxygen to the ambient pressure up to 25,000 ft. and thereafter the pressures remain constant. The apparatus comprises a connector having a lower part 12 (Fig. 2) attached to the aircraft and an upper part 20 attached to the airman's seat. Air under pressure is supplied through a conduit 10 to a chamber 11 and passes two valves 16 and 28 to enter a conduit 19. Oxygen enters through a conduit 13 and passes a valve 33 to enter a conduit 30. A passage connecting the air and oxygen inlets is closed by a valve 22 which is held shut by the diaphragm 24, against the pressure of the spring 27, as long as the air chamber pressure exceeds the ambient pressure. Air in the conduit 19 passes to a pressure regulator 21 through a valve 39 and hence by a conduit 48 to the suit. The pressure in the chamber 40 acts on a diaphragm 41 and tends to shut the valve, but is resisted by a spring 43 and the ambient pressure, which is admitted through a port 45. This results in the suit pressure always being slightly above the ambient pressure. At a height of 25,000 ft. the capsule 47 expands and closes the port 45 to prevent a drop in the suit supply pressure at higher altitudes. The suit vent valve 52 is spring loaded to keep the suit at a pressure slightly above ambient and at a height of 25,000 ft. the pressure is augmented by the expansion of a partially evacuated capsule. Oxygen passes from the conduit 30 through a valve 55 and hence through a conduit 61 to the helmet. The pressure in the chamber 56 acts on a diaphragm 58 and tends to close the valve 55, but is resisted by the spring 60 and the air pressure in the chamber 40 so that the oxygen pressure is always slightly higher than the suit pressure. Oxygen enters the helmet through a check valve 64 and is exhaled through a valve 65 against the action of a spring 66 and the oxygen pressure in the branch conduit 67. In the event of failure of the aircraft pressure air supply the valve 16 shuts and the valve 22 opens and both conduits 19 and 30 are supplied from the aircraft oxygen supply. When the two ports 12 and 20 of the connector are separated the supports 34 and 29 are removed and allow the valves 33 and 28 to close and the valve 36 opens and connects the conduits 19 and 30, which are both supplied from the emergency oxygen supply 32. In a modification, Fig. 4, the oxygen pressure regulator valve 55 is controlled by ambient pressure acting on the diaphragm 58 through a port 78 which is closed at a height of 25,000 ft. by the expansion of a capsule 82, and the suit pressure regulator valve 68 is controlled by a diaphragm 69 which is mechanically connected to a diaphragm 73. The diaphragm 69, which tends to close the valve is acted on by a spring 75 and also by the pressure in the suit which is communicated by a duct 74 leaving the suit near the vent valve, while the diaphragm 73 which tends to open the valve is acted on by the pressure of oxygen in the chamber 56 so that the suit is controlled at a pressure slightly above the ambient pressure.