Oxygen-rich gas breathing systems for passenger carrying aircraft

• US 5,199,423 A
• Filed: 02/06/1991
• Issued: 04/06/1993
• Est. Priority Date: 02/10/1990
• Status: Expired due to Fees

• Current Assignee: Honeywell Normalair-Garrett Ltd. (Honeywell International Inc.)
• Original Assignee: Honeywell Normalair-Garrett Ltd. (Honeywell International Inc.)
• Inventors: Searle, Robin H. J., Harral, Michael W.
• Primary Examiner(s): Millin, V.
• Assistant Examiner(s): Passaniti, Sebastiano
• Application Number:
  US07/651,192
• Time in Patent Office: 790 Days
• Field of Search: 128/204.15, 128/204.16, 128/204.18, 128/204.24, 128/204.25, 128/205.18, 128/205.24, 128/204.21, 128/204.22, 128/204.29, 128/202.2 6
• US Class Current: 128/202.26
• CPC Class Codes: A62B 7/14 for high-altitude aircraft
• CPC Class Codes: B64D 10/00 Flight suits helmets in general A42B3/00; breathing helmets A62B18/00
• CPC Class Codes: B64D 13/00 Arrangements or adaptations of air-treatment apparatus for aircraft crew or passengers, or freight space , or structural parts of the aircraft treatment rooms with artificial climate for medical purposes A61G10/02; respiratory apparatus in general A62B; for vehicles in general B60H
• CPC Class Codes: B64D 2013/0677 comprising on board oxygen generator systems

Abstract

A system and apparatus are disclosed for providing oxygen-rich gas for breathing by aircrew and passengers of commercial passenger aircraft. Oxygen-rich gas output by molecular sieve concentrator apparatus 11 is delivered by way of a compressor 17 and a priority valve 24 to a flight crew gas storage cylinder 22 and passenger gas storage cylinders 23. An electronic control unit (ECU) 38 controls cycling of the concentrator apparatus 11 in obtainment of gas enriched with oxygen to at least 90%. The ECU is connected for receiving signals from a monitor 35 which senses the content of oxygen in gas delivered by the concentrator apparatus. The ECU receives signals from pressure sensors 42 and 43 in the cylinders 22 and 23 to initiate start up of the system when the content of these cylinders is sensed to have fallen below a predetermined value. The ECU is connected to switch the priority valve for preferential charging of the crew cylinder when both sets of cylinders require charging. The ECU is further connected for opening a vent valve 46 whereby on start-up of the system, gas delivered by the concentrator apparatus is vented to ambient until the oxygen concentration is sensed to be 90% or more. The system reduces the requirement for ground servicing and weight of oxygen gas storage cylinders carried by present day passenger carrying aircraft. Also, it enables the number of cylinders to be kept at a minimum in meeting the requirements for emergency oxygen on new air routes which are now being developed.

Claims

1. Apparatus for supplying oxygen-rich gas for breathing by crew and passengers of a passenger carrying aircraft, comprising first gas storage means adapted for pre-charging with oxygen-rich gas and connected by first supply line means for delivering said oxygen-rich gas to an aircraft flight crew cabin for continuous breathing by a flight crew member flying the aircraft above a predetermined altitude and for breathing by all flight crew in the event of cabin decompression;

second gas storage means adapted for pre-charging with oxygen-rich gas and connected by second supply line means for delivering said oxygen-rich gas for breathing by occupants of an aircraft passenger cabin in the event of cabin decompression;

means for monitoring the content of oxygen-rich gas in the first and second gas storage means;

molecular sieve oxygen concentrator means having a supply air inlet end and an oxygen-rich gas outlet end;

supply air delivery means adapted for connection between a source of supply air and the inlet end of the concentrator means;

oxygen-rich gas delivery means adapted for connection between the outlet end of the concentrator means and the first and second gas storage means;

means for sensing the content of oxygen-rich gas in the first and second gas storage means;

means for initiating operation of the concentrator means when the content of oxygen-rich gas in one or both of the first and second gas storage means is sensed to have fallen below a required content value;

means for monitoring the content of oxygen in oxygen-rich gas delivered by the concentrator means;

spill valve means connected in the oxygen-rich gas delivery means;

means connecting the spill valve means with the oxygen-rich gas sensing means whereby the spill valve means is signalled by the sensing means to open and vent to ambient oxygen-rich gas delivered by the concentrator means when the oxygen content of said gas is sensed as being below a required value;

compressor means connected in the oxygen-rich gas delivery means;

means connecting the compressor means with the oxygen-rich gas sensing means whereby the spill valve means is signalled to close and the compressor means is signalled to commence operating to increase the pressure of oxygen rich gas delivered by the concentrator means when the content of said gas is sensed to be above the required value for delivery to the first and second gas storage means.

2. A method of supplying oxygen-rich gas for breathing by crew and passengers of a passenger carrying aircraft comprising the steps of:

delivering oxygen-rich gas from first gas storage means pre-charged with oxygen-rich gas to an aircraft flight crew cabin for continuous breathing by a flight crew member flying the aircraft during flight above a predetermined altitude and for breathing by all flight crew members in the event of cabin decompression;

delivering oxygen-rich gas from second gas storage means pre-charged with oxygen-rich gas to an aircraft passenger cabin for breathing by occupants of the passenger cabin in the event of cabin decompression;

monitoring the content of oxygen-rich gas in the first and second gas storage means;

initiating operation of molecular sieve oxygen concentrator means located on-board of the aircraft to produce oxygen-rich gas when the content of oxygen-rich gas in one or both of the first and second gas storage means is sensed to have fallen below a required content value;

sensing the content of oxygen in oxygen-rich gas delivered by the concentrator means;

venting to ambient oxygen-rich gas delivered by the concentrator means when the oxygen content of said gas is sensed as being below a required value;

increasing the pressure of oxygen-rich gas delivered by the concentrator means when the oxygen content of said gas is sensed as being above the required value;

delivering the oxygen-rich gas at increasing pressure for charging the first and second storage means.

3. A method according to claim 2, including the step of priority charging the first gas storage means and thereafter charging the second gas storage means when the content of both the first and second gas storage means is sensed to have fallen below their required content value.

4. A method according to claim 2, including the step of pre-charging the first and second gas storage means with 100% gaseous oxygen from a ground station.

5. Apparatus for generating oxygen-rich gas for a system supplying oxygen-rich gas for breathing by crew and passengers of a passenger carrying aircraft, comprising a plurality of multi-bed molecular sieve oxygen concentrators each having a supply air inlet end and an oxygen-rich gas outlet end, supply air inlet means adapted for connection to a source of supply air and including pressure regulating means and manifold means connected for distributing supply air to the inlet ends of the concentrators, means for monitoring the content of oxygen in oxygen-rich gas delivered by the concentrators, control means responsive to signals from the oxygen content monitor for controlling cycling of the concentrator beds between on-stream/charge and off-stream/purge phase whereby gas enriched with oxygen to substantially maximum concentration is delivered at the outlet ends of the concentrators, manifold means connected to the outlet ends of the concentrators for receiving oxygen-rich gas delivered by the concentrators, compressor means including inlet means connected to the oxygen-rich gas manifold means for receiving said gas and operable to increase the pressure of said gas for delivery from compressor outlet means, the compressor means comprising a common compressor connected for receiving oxygen-rich gas from each of the concentrators, the compressor further comprising oxygen-rich gas pressurizing piston and cylinder assemblies adapted to be driven by supply air, wherein supply air for driving the piston and cylinder assemblies is delivered to the compressor from the supply air delivery means by way of a duct having the multi-bed concentrators arranged therearound.

6. Apparatus for generating oxygen-rich gas for a system supplying oxygen-rich gas for breathing by crew and passengers of a passenger carrying aircraft, comprising a plurality of multi-bed molecular sieve oxygen concentrators each having a supply air inlet end and an oxygen-rich gas outlet end, supply air inlet means adapted for connection to a source of supply air and including pressure regulating means and manifold means connected for distributing supply air to the inlet ends of the concentrators, means for monitoring the content of oxygen in oxygen-rich gas delivered by the concentrators, control means responsive to signals from the oxygen content monitor means for controlling cycling of the concentrator beds between on-stream/charge and off-steam/purge phase whereby gas enriched with oxygen to substantially maximum concentration is delivered at the outlet ends of the concentrators, manifold means connected to the outlet ends of the concentrators for receiving oxygen-rich gas delivered by the concentrators, compressor means including inlet means connected to the oxygen-rich gas manifold means for receiving said gas and operable to increase the pressure of said gas for delivery from compressor outlet means, and oxygen content monitor means associated with each concentrator so that the oxygen content of oxygen-rich gas delivered by each concentrator is separately monitored and means are provided for shutting down and isolating an individual concentrator in the event of malfunction.