Backup breathing gas supply for an oxygen concentrator system

• US 4,870,960 A
• Filed: 06/12/1987
• Issued: 10/03/1989
• Est. Priority Date: 10/07/1985
• Status: Expired due to Term

• Current Assignee: Carleton Life Support Systems, Inc. (Cobham PLC)
• Original Assignee: Litton Systems Incorporated
• Inventors: Hradek, Richard W.
• Primary Examiner(s): Hindenburg, Max
• Assistant Examiner(s): Lackyk, J. P.
• Application Number:
  US07/062,131
• Time in Patent Office: 844 Days
• Field of Search: 128/202.26, 128/204.18, 128/205.12, 128/205.14, 128/202.22, 55/21, 55/25
• US Class Current: 128/202.22
• CPC Class Codes: B01D 2253/108 Zeolites
• CPC Class Codes: B01D 2253/116 Molecular sieves other than zeolites
• CPC Class Codes: B01D 2256/12 Oxygen
• CPC Class Codes: B01D 2257/102 Nitrogen
• CPC Class Codes: B01D 2259/40005 using rotary valves
• CPC Class Codes: B01D 2259/40009 using sensors or gas analysers
• CPC Class Codes: B01D 2259/402 using two beds
• CPC Class Codes: B01D 2259/4575 in aeroplanes or space ships
• CPC Class Codes: B01D 53/0446 Means for feeding or distributing gases
• CPC Class Codes: B01D 53/047 Pressure swing adsorption
• CPC Class Codes: B01D 53/053 with storage or buffer vessel

Abstract

A backup breathing gas supply is used with an oxygen concentrator system in which breathing gas is derived as an oxygen enriched product gas from the oxygen concentrator system and delivered to a breathing regulator. The backup breathing gas supply includes a plenum chamber for storing a quantity of breathing gas, a plenum line coupling the output of the oxygen concentrator to the plenum chamber, and a bypass line coupled to the output of the oxygen concentrator. During normal operation, breathing gas is delivered by means of the bypass line. In the event of loss of air supply to the concentrator, loss of electrical power, or concentrator breakdown, breathing gas is delivered from the plenum chamber. A three-way control valve is used to selectively couple either the plenum chamber or the bypass line to the system outlet. A quantity of molecular sieve material is contained in the plenum chamber to increase the capacity of the chamber to contain breathing gas beyond its capacity without molecular sieve material.

Claims

1. A backup breathing gas supply for use with an oxygen concentrator in which a source gas is coupled by a rotary valve to a plurality of beds of molecular sieve material in the concentrator to produce an enriched product gas at the concentrator outlet for delivery as a breathing gas to a breathing regulator, wherein the rotary valve periodically alternates the flow of the source gas to the plurality of beds of molecular sieve material in order to produce breathing gas, the backup breathing gas supply comprising:

a plenum chamber for storing a quantity of breathing gas,

a quantity of molecular sieve material contained in the plenum chamber, whereby the capacity of plenum chamber to contain breathing gas is increased by the addition of molecular sieve material,

a plenum line coupling the outlet of the oxygen concentrator to the plenum chamber,

a bypass line coupled to the outlet of the oxygen concentrator in parallel with the plenum line,

control means for selectively coupling either the plenum chamber or the bypass line to the breathing regulator, said control means comprising a three-way valve coupled to the outlet of the plenum chamber and the bypass line,

a check valve in the plenum line upstream of the plenum chamber whereby breathing gas fills said plenum chamber whenever the concentrator outlet pressure exceeds the plenum pressure, and whereby loss of stored gas from the plenum input through the bypass line to the breathing regulator when the concentrator outlet pressure is less than the plenum pressure is prevented,

a rotation sensor means for detecting the failure of the rotary valve, said sensor means causing said control means to deliver breathing gas from the plenum chamber to the breathing regulator upon said failure, and

restrictor means in the plenum line upstream of the plenum chamber for limiting the fill rate of the plenum chamber during periods when the concentrator output pressure exceeds the plenum pressure.

2. The backup breathing gas supply of claim 1 further comprising:

sensor means for detecting a loss of pressure in the bypass line, said sensor means causing said control means to deliver breathing gas from the plenum chamber to the breathing regulator.