Method and apparatus for filling portable high pressure cylinders with respiratory oxygen

1. An apparatus for providing oxygen-enriched gas for use by a patient in the form of a portable tank of the oxygen-enriched gas, said apparatus comprising:

an oxygen concentrator for providing oxygen-enriched gas, said concentrator having a first output and a second output;

a compressor connected in fluid communication with said first output of said concentrator for compressing oxygen-enriched gas provided by said concentrator, said compressor having an output;

a coupling connected in fluid communication with said output of said compressor, said coupling adapted to be connected with a portable tank to enable filling of the portable tank with compressed oxygen-enriched gas from the compressor; and

a reservoir connected in fluid communication with said output of said compressor for receiving compressed oxygen-enriched gas from said compressor;

said reservoir being connected in fluid communication with said coupling to enable flow of compressed oxygen-enriched gas from said reservoir to said coupling to enable filling of the portable tank with compressed oxygen-enriched gas from said reservoir.

2. An apparatus as set forth in claim 1 wherein said reservoir has a capacity in of at least about 1,000 standard liters.

3. An apparatus as set forth in claim 1 further comprising a patient device for providing oxygen-enriched gas to a patient, said patient device being connected with said second output of said concentrator.

4. An apparatus as set forth in claim 1 further comprising a portable tank for ambulatory use by a patient, and wherein said reservoir has a capacity in the range of from three times the capacity of said portable tank to fifty times the capacity of said portable tank.

5. An apparatus as set forth in claim 4 wherein said portable tank has a capacity in the range from about 144 to about 248 standard liters, and wherein said reservoir has a capacity of in the range of from about 1,000 standard liters to about 5,000 standard liters.

6. An apparatus as set forth in claim 1 wherein said reservoir has a capacity sufficient to fill about one to four portable tanks with gas under pressure of at least about 1,700 psi.

7. An apparatus as set forth in claim 1 wherein said reservoir has a capacity in the range of from about 1,000 standard liters to about 5,000 standard liters.

8. An apparatus as set forth in claim 7 wherein said reservoir has a capacity of 3,452 standard liters.

9. An apparatus as set forth in claim 1 wherein said reservoir has a capacity sufficient to fill in one minute or less, to a pressure of at least about 1,800 psi, a portable tank having a capacity in the range of from about 100 standard liters to about 300 standard liters.

10. An apparatus as set forth in claim 1 further including a flow restrictor between said reservoir and said coupling for controlling the rate of flow of oxygen-enriched gas from said reservoir to said coupling.

11. An apparatus as set forth in claim 1 further comprising a pressure switch connected in fluid communication with said reservoir for helping to control operation of said compressor.

12. An apparatus as set forth in claim 11 wherein said pressure switch is operative to sense the pressure in said reservoir and to turn on said compressor when the pressure in said reservoir drops below a predetermined minimum pressure and to turn off said compressor when the pressure in said reservoir reaches a predetermined maximum pressure.

13. An apparatus as set forth in claim 1 further comprising a check valve for blocking fluid flow from said reservoir to said compressor while allowing fluid flow from said compressor to said reservoir.

14. An apparatus as set forth in claim 1 including a first fluid flow conduit connected with said first output of said compressor, a second fluid flow conduit connected with said coupling, a tee connection between said first and second fluid flow conduits, and a third conduit connected between said reservoir and said tee connection.

15. An apparatus as set forth in claim 14 further comprising a pressure switch for sensing pressure in said reservoir and for helping to control operation of said compressor.

16. An apparatus as set forth in claim 15 further comprising a check valve for blocking fluid flow from said reservoir to said compressor while allowing fluid flow from said compressor to said reservoir, said check valve being disposed between said pressure switch and said compressor.

17. A method of filling a portable tank with compressed oxygen-enriched gas, said method comprising the steps of:

providing a coupling such that when a portable tank is connected with the coupling oxygen-enriched gas can flow through the coupling into the portable tank;

directing oxygen-enriched gas from an oxygen concentrator to a compressor;

compressing the oxygen-enriched gas in the compressor;

directing compressed oxygen-enriched gas from the compressor to a reservoir;

storing the compressed oxygen-enriched gas in the reservoir; and thereafter

directing stored oxygen-enriched gas from the reservoir to the coupling to enable filling of a portable tank with compressed oxygen-enriched gas from the reservoir.

18. A method as set forth in claim 17 wherein said storing step comprises storing the compressed oxygen-enriched gas in a reservoir having a capacity of at least about 1,000 standard liters.

19. A method as set forth in claim 17 further comprising the step of directing compressed oxygen-enriched gas from the compressor to the reservoir to refill the reservoir, after performing said step of directing stored oxygen-enriched gas from the reservoir to the coupling.

20. A method comprising the steps of:

providing oxygen-enriched gas from an oxygen concentrator;

directing a first portion of the oxygen-enriched gas from the concentrator to a patient device;

simultaneously directing a second portion of the oxygen-enriched gas from the concentrator to a compressor;

compressing the second portion of the oxygen-enriched gas in the compressor;

directing the compressed oxygen-enriched gas from the compressor to a reservoir; and

storing the compressed oxygen-enriched gas in the reservoir.

21. A method as set forth in claim 20 further comprising the steps of:

providing a coupling such that when a portable tank is connected with the coupling oxygen-enriched gas can flow through the coupling into the portable tank; and

directing stored compressed oxygen-enriched gas from the reservoir to the coupling to enable filling of a portable tank with compressed oxygen-enriched gas from the reservoir.

22. A method comprising the steps of:

providing a coupling such that when a portable tank is connected with the coupling oxygen-enriched gas can flow through the coupling into the portable tank;

directing stored oxygen-enriched gas from a reservoir having a capacity of at least about 1,000 standard liters to the coupling to enable filling of a portable tank with stored oxygen-enriched gas from the reservoir;

sensing the pressure in the reservoir;

directing oxygen-enriched gas from an oxygen concentrator to a compressor;

actuating the compressor when the sensed pressure in the reservoir is less than a predetermined minimum pressure; and

filling the reservoir with compressed oxygen enriched gas from the compressor.

23. A method as set forth in claim 22 further comprising the step of directing compressed oxygen-enriched gas from the compressor to the coupling, performed simultaneously with said step of directing stored oxygen-enriched gas from the reservoir to the coupling.