Apparatus and method of providing concentrated product gas

• US 7,455,717 B2
• Filed: 10/25/2005
• Issued: 11/25/2008
• Est. Priority Date: 10/25/2004
• Status: Active Grant

• Current Assignee: Ventec Life Systems, Inc.
• Original Assignee: Invacare Corporation
• Inventors: Sprinkle, Thomas B.
• Primary Examiner(s): LAWRENCE JR, FRANK M
• Application Number:
  US11/258,480
• Publication Number:
  US 20060086251A1
• Time in Patent Office: 1,127 Days
• Field of Search: 95/22, 95 95-106, 951/30, 961/08, 961/21, 961/15, 961/16, 128/204.21, 128/204.23, 128/204.26, 128/205.24
• US Class Current: 95/22
• CPC Class Codes: B01D 2253/108 Zeolites
• CPC Class Codes: B01D 2253/308 Pore size
• CPC Class Codes: B01D 2256/12 Oxygen
• CPC Class Codes: B01D 2257/102 Nitrogen
• CPC Class Codes: B01D 2259/40009 using sensors or gas analysers
• CPC Class Codes: B01D 2259/402 using two beds
• CPC Class Codes: B01D 2259/4533 for medical purposes
• CPC Class Codes: B01D 53/047 Pressure swing adsorption
• CPC Class Codes: B01D 53/0476 Vacuum pressure swing adsorption

Abstract

In one aspect, a product gas concentrator is provided. In one embodiment, the apparatus may include: a first process separating adsorbable components from a source gaseous mixture, a second process providing concentrated product gas in a continuous output mode, a third process providing concentrated product gas in a pulsed output mode, and a fourth process selectively switching between the continuous and pulsed output modes. In another embodiment, the apparatus may include: a first process pressurizing a source gaseous mixture, a second process separating adsorbable components from the pressurized gaseous mixture, a product tank accumulating concentrated product gas for dispensing, an output path, a third process selecting a volume to be dispensed during a predetermined time, a pressure sensor monitoring pressure of the concentrated product gas, and a fourth process controlling flow of the concentrated product gas in response to the selected volume and the monitored pressure.

Claims

1. An apparatus for providing a concentrated product gas, including:

a gaseous component separation subsystem separating one or more adsorbable components from a source gaseous mixture to form a concentrated product gas;

a continuous gas output adapted to provide the concentrated product gas in a continuous output mode;

a pulsed gas output adapted to provide the concentrated product gas in a pulsed output mode; and

a mode selection logic selectively switching between the continuous output mode and the pulsed output mode, the mode selection logic including;

inspiration detection logic detecting inspiration by a user receiving the concentrated product gas in the pulsed output mode; and

means for halting operation of the apparatus after no inspiration has been detected for a predetermined time.

2. The apparatus of claim 1, the mode selection logic including:

an AC power source detection logic detecting that the apparatus is connected to an AC power source;

a default output mode selection logic selecting the continuous output mode as a default output mode after connection to the AC power source is detected; and

means for providing the concentrated product gas in the default output mode after initializing or resetting the apparatus.

3. The apparatus of claim 1, the mode selection logic including:

one or more input devices adapted for selection of the continuous output mode or the pulsed output mode by a user; and

means for selectively switching from the continuous output mode to the pulsed output mode and vice versa in response to a corresponding activation of the one or more input devices.

4. A method of providing a concentrated product gas, including:

a) separating one or more adsorbable components from a source gaseous mixture to form a concentrated product gas;

b) providing the concentrated product gas in a continuous output mode or in a pulsed output mode;

c) in response to a predetermined condition, selectively switching between the continuous output mode and the pulsed output mode;

d) detecting inspiration by a user receiving the concentrated product gas in the pulsed output mode; and

e) halting operation after no inspiration has been detected for a predetermined time.

5. The method of claim 4, further including:

f) detecting connection to an AC power source;

g) selecting the continuous output mode as a default output mode after connection to the AC power source is detected; and

h) providing the concentrated product gas in the default output mode after initializing or resetting.

6. The method of claim 4, further including:

f) providing one or more input devices adapted for selection of the continuous output mode or the pulsed output mode by a user; and

g) selectively switching from the continuous output mode to the pulsed output mode and vice versa in response to a corresponding activation of the one or more input devices.

7. An apparatus for providing a concentrated product gas, including:

a pressurizing device pressurizing a source gaseous mixture to form a pressurized gaseous mixture;

a gaseous component separation subsystem separating one or more adsorbable components from the pressurized gaseous mixture to form a concentrated product gas;

a product tank in communication with the gaseous component separation subsystem, the product tank accumulating a volume of the concentrated product gas for dispensing;

an output path in communication with the product tank and adapted to selectively dispense the concentrated product gas;

a volume selection logic selecting a volume of concentrated product gas to be dispensed via the output path during a predetermined time;

a pressure sensor monitoring a pressure of the concentrated product gas in the output path; and

means for controlling a flow of the concentrated product gas though the output path in response to the selected volume and the monitored pressure.

8. The apparatus of claim 7 wherein the concentrated product gas is provided in a continuous output mode or a pulsed output mode;

the pressurizing device including;

a compressor adapted to pressurize the source gaseous mixture to form the pressurized gaseous mixture; and

a variable speed drive motor in operative communication with the compressor and adapted to drive the compressor at a corresponding speed; and

the means for controlling including;

means for operating the variable speed drive motor at a speed corresponding to the selected volume; and

means for adjusting the speed of the variable speed drive motor in response to at least one of the monitored pressure and the selected volume.

9. The apparatus of claim 7 wherein the concentrated product gas is provided in a continuous output mode;

the output path including;

a proportional flow control valve adapted to proportionately move between a closed position and an open position in relation to a variable control signal; and

the means for controlling including;

means for setting the variable control signal to a level corresponding to the selected volume; and

means for adjusting the level of the variable control signal in response to at least one of the monitored pressure and the selected volume.

10. The apparatus of claim 9 wherein:

the gaseous component separation subsystem further including;

first and second sieve beds, each adapted to selectively receive the pressurized gaseous mixture, separate the one or more adsorbable components from the pressurized gaseous mixture, and provide the concentrated product gas to the product tank; and

a cross-over switching valve adapted to selectively switch between a first position connecting the pressurized gaseous mixture to the first sieve bed and a second position connecting the pressurized gaseous mixture to the second sieve bed;

the means for controlling further including;

means for periodically changing the cross-over switching valve between the first and second positions to define a separating cycle with a first portion in which the first sieve bed receives the pressurized gaseous mixture and a second portion in which the second sieve bed receives the pressurized gaseous mixture;

wherein the first portion includes a first segment in which the first sieve bed separates the one or more adsorbable components from the pressurized gaseous mixture and a second segment in which the first sieve bed continues separating the one or more adsorbable components from the pressurized gaseous mixture and provides the concentrated product gas to the product tank;

wherein the second portion includes a third segment in which the second sieve bed separates the one or more adsorbable components from the pressurized gaseous mixture and a fourth segment in which the second sieve bed continues separating the one or more adsorbable components from the pressurized gaseous mixture and provides the concentrated product gas to the product tank; and

the means for adjusting further including;

means for comparing a first monitored pressure associated with a transition from the first portion of the separating cycle to the second portion to a second monitored pressure during the third segment of the separating cycle to identify a first pressure decay;

means for determining a first volume of continuous concentrated product gas dispensed from the output path in relation to the first pressure decay;

means for comparing the first volume to the selected volume in relation to a known time between the first and second monitored pressures to determine a first coarse adjustment associated with a current level of the variable control signal; and

means for changing the current level of the variable control signal in relation to the first coarse adjustment.

11. The apparatus of claim 9, the means for adjusting further including:

means for periodically using a predetermined factor of a current monitored pressure to identify a current fine adjustment associated with a current level of the variable control signal; and

means for changing the current level of the variable control signal in relation to the current fine adjustment.

12. The apparatus of claim 7 wherein the concentrated product gas is provided in a pulsed output mode;

the output path including;

an output port adapted to provide the concentrated product gas to a user;

an inspiration path including a vent port adapted to receive atmospheric air and a flow sensor adapted to sense flow though the inspiration path, the inspiration path having an outlet end opposite the vent port; and

a two-position flow control valve adapted to selectively switch between a first position connecting the outlet end of the inspiration path to the outlet port and a second position connecting the output path from the product tank to the output port; and

the means for controlling including;

first means for switching the two-position flow control valve to the second position in response to detecting flow through the inspiration path above a predetermined threshold when the two-position flow control valve is in the first position; and

second means for switching the two-position flow control valve from the second position to the first position in response to at least one of the selected volume and the monitored pressure.

13. The apparatus of claim 12, the means for controlling further including:

means for determining a breath rate associated with the user based on a sequence of detections of flow through the inspiration path above the predetermined threshold between switching cycles of the two-position flow control valve;

wherein the second means for switching the two-position flow control valve from the second position to the first position is also based at least in part on the determined breath rate.

14. The apparatus of claim 13, the second means for switching including:

means for determining a time required to dispense the selected volume of concentrated product gas in relation to the monitored pressure and the determined breath rate; and

means for allocating the determined time to pulse durations associated with individual pulses of concentrated product gas over the determined time;

wherein the second means for switching the two position flow control valve from the second position to the first position is based on a corresponding pulse duration for a current individual pulse of concentrated product gas.

15. A method of providing a concentrated product gas, including:

a) pressurizing a source gaseous mixture to form a pressurized gaseous mixture;

b) separating one or more adsorbable components from the pressurized gaseous mixture to form a concentrated product gas;

c) accumulating a volume of the concentrated product gas in a product tank for dispensing via an output path;

d) selecting a volume of concentrated product gas to be dispensed via the output path during a predetermined time;

e) monitoring a pressure of the concentrated product gas in the output path; and

f) controlling a flow of the concentrated product gas through the output path in response to the selected volume and the monitored pressure.

16. The method of claim 15 wherein the concentrated product gas is provided in a continuous output mode or a pulsed output mode, the method further including:

g) providing a compressor adapted to pressurize the source gaseous mixture to form the pressurized gaseous mixture;

h) providing a variable speed drive motor in operative communication with the compressor and adapted to drive the compressor at a corresponding speed;

i) operating the variable speed drive motor at a speed corresponding to the selected volume; and

j) adjusting the speed of the variable speed drive motor in response to at least one of the monitored pressure and the selected volume.

17. The method of claim 15 wherein the concentrated product gas is provided in a continuous output mode, the method further including:

g) providing a proportional flow control valve adapted to proportionately move between a closed position and an open position in relation to a variable control signal;

h) setting the variable control signal to a level corresponding to the selected volume; and

i) adjusting the level of the variable control signal in response to at least one of the monitored pressure and the selected volume.

18. The method of claim 17, further including:

j) providing first and second sieve beds, each adapted to selectively receive the pressurized gaseous mixture, separate the one or more adsorbable components from the pressurized gaseous mixture, and provide the concentrated product gas to the product tank;

k) providing a cross-over switching valve adapted to selectively switch between a first position connecting the pressurized gaseous mixture to the first sieve bed and a second position connecting the pressurized gaseous mixture to the second sieve bed;

l) periodically changing the cross-over switching valve between the first and second positions to define a separating cycle with a first portion in which the first sieve bed receives the pressurized gaseous mixture and a second portion in which the second sieve bed receives the pressurized gaseous mixture, wherein the first portion includes a first segment in which the first sieve bed separates the one or more adsorbable components from the pressurized gaseous mixture and a second segment in which the first sieve bed continues separating the one or more adsorbable components from the pressurized gaseous mixture and provides the concentrated product gas to the product tank, wherein the second portion includes a third segment in which the second sieve bed separates the one or more adsorbable components from the pressurized gaseous mixture and a fourth segment in which the second sieve bed continues separating the one or more adsorbable components from the pressurized gaseous mixture and provides the concentrated product gas to the product tank; and

m) comparing a first monitored pressure associated with a transition from the first portion of the separating cycle to the second portion to a second monitored pressure during the third segment of the separating cycle to identify a first pressure decay;

n) determining a first volume of concentrated product gas dispensed from the product tank in relation to the first pressure decay;

o) comparing the first volume to the selected volume in relation to a known time between the first and second monitored pressures to determine a first coarse adjustment associated with a current level of the variable control signal; and

p) changing the current level of the variable control signal in relation to the first coarse adjustment.

19. The method of claim 17, further including:

j) periodically using a predetermined factor of a current monitored pressure to identify a current fine adjustment associated with a current level of the variable control signal; and

k) changing the current level of the variable control signal in relation to the current fine adjustment.

20. The method of claim 15 wherein the concentrated product gas is provided in a pulsed output mode, the method further including:

g) providing an output port adapted to provide the concentrated product gas to a user;

h) providing an inspiration path including a vent port adapted to receive atmospheric air and a flow sensor adapted to sense flow through the inspiration path, the inspiration path having an outlet end opposite the vent port;

i) providing a two-position flow control valve adapted to selectively switch between a first position connecting the outlet end of the inspiration path to the outlet port and a second position connecting the output path from the product tank to the output port;

j) switching the two-position flow control valve to the second position in response to detecting flow through the inspiration path above a predetermined threshold when the two-position flow control valve is in the first position; and

k) switching the two-position flow control valve from the second position to the first position in response to at least one of the selected volume and the monitored pressure.

21. The method of claim 20, further including:

l) determining a breath rate associated with the user based on a sequence of detections of flow through the inspiration path above the predetermined threshold between switching cycles of the two-position flow control valve, wherein the switching in k) is also based at least in part on the determined breath rate.

22. The method of claim 21, further including:

m) determining a time required to dispense the selected volume of concentrated product gas in relation to the monitored pressure and the determined breath rate; and

n) allocating the determined time to pulse durations associated with individual pulses of concentrated product gas over the determined time, wherein the switching in k) is based on a corresponding pulse duration for a current individual pulse of concentrated product gas.

23. An apparatus for providing a concentrated product gas, including:

a gaseous component separation subsystem separating one or more adsorbable components from a source gaseous mixture to form a concentrated product gas;

a continuous gas output adapted to provide the concentrated product gas in a continuous output mode;

a pulsed gas output adapted to provide the concentrated product gas in a pulsed output mode; and

a mode selection logic selectively switching between the continuous output mode and the pulsed output mode, the mode selection logic including;

an AC power source detection logic detecting that the apparatus is connected to an AC power source;

a default output mode selection logic selecting the continuous output mode as a default output mode after connection to the AC power source is detected; and

means for providing the concentrated product gas in the default output mode after initializing or resetting the apparatus.

24. The apparatus of claim 23, the mode selection logic including:

an inspiration detection logic detecting inspiration by a user receiving the concentrated product gas in the pulsed output mode; and

means for switching to the continuous output mode after no inspiration has been detected for a predetermined time.

25. The apparatus of claim 23, the mode selection logic including:

one or more input devices adapted for selection of the continuous output mode or the pulsed output mode by a user; and

means for selectively switching from the continuous output mode to the pulsed output mode and vice versa in response to a corresponding activation of the one or more input devices.

26. A method of providing a concentrated product gas, including:

a) separating one or more adsorbable components from a source gaseous mixture to form a concentrated product gas;

b) providing the concentrated product gas in a continuous output mode or in a pulsed output mode;

c) in response to a predetermined condition, selectively switching between the continuous output mode and the pulsed output mode;

d) detecting connection to an AC power source;

e) selecting the continuous output mode as a default output mode after connection to the AC power source is detected; and

f) providing the concentrated product gas in the default output mode after initializing or resetting.

27. The method of claim 26, further including:

g) detecting inspiration by a user receiving the concentrated product gas in the pulsed output mode; and

h) switching to the continuous output mode after no inspiration has been detected for a predetermined time.

28. The method of claim 26, further including:

g) providing one or more input devices adapted for selection of the continuous output mode or the pulsed output mode by a user; and

h) selectively switching from the continuous output mode to the pulsed output mode and vice versa in response to a corresponding activation of the one or more input devices.