초록 ▼

A gas fractionalization apparatus and methods for providing oxygen rich air to patients are disclosed. The apparatus comprises a variable output compressor, a PSA unit, a control system, and one or more pressure sensing devices. Pressure of the oxygen rich gas is maintained within a selected window

A gas fractionalization apparatus and methods for providing oxygen rich air to patients are disclosed. The apparatus comprises a variable output compressor, a PSA unit, a control system, and one or more pressure sensing devices. Pressure of the oxygen rich gas is maintained within a selected window by adjusting the output of the compressor in response to changes in the pressure of the oxygen rich gas. Methods of feedback control are further provided for calibration of the compressor under factory and in-service conditions, as well as under high-altitude conditions. Methods for providing diagnostic estimates and alarms of time to service are further provided.

대표청구항 ▼

What is claimed is: 1. A method of producing an oxygen rich gas, comprising: providing ambient air to a compressor; pressuring said ambient air in the compressor; delivering the pressurized air from the compressor to a PSA unit; processing said pressurized air in the PSA unit in accordance with a P

What is claimed is: 1. A method of producing an oxygen rich gas, comprising: providing ambient air to a compressor; pressuring said ambient air in the compressor; delivering the pressurized air from the compressor to a PSA unit; processing said pressurized air in the PSA unit in accordance with a PSA cycle so as to produce an oxygen rich gas; measuring the pressure of the oxygen rich gas; maintaining the pressure of the oxygen rich gas at one or more pre-selected levels by adjusting an output pressure of the compressor; and wherein the output pressure of the compressor is adjusted based on the measured pressure of the oxygen rich gas inside a containing space, wherein measured pressure of the oxygen rich gas comprises an average of a plurality of sampled pressure values obtained during a selected time period. 2. The method of claim 1, wherein the pressure of the oxygen rich gas is generally in phase with the PSA cycle, and wherein the sampled pressure values correspond to peak values of the cyclic profile of oxygen rich gas pressure. 3. The method of claim 1, wherein the selected time period includes N sampled pressure values, such that averaging of the N values reduces the likelihood that the adjustment of the output pressure will be triggered by spurious fluctuations of individual sampled pressure values. 4. The method of claim 3, wherein the N sampled pressure values correspond to N breathing cycles. 5. The method of claim 3, wherein the selected time period begins anew when an error condition occurs during the current time period. 6. The method of claim 1, wherein the output pressure of the compressor is adjusted by adjusting a pumping speed of the compressor. 7. The method of claim 1, wherein the output of the compressor is adjusted by adjusting a displacement of the compressor. 8. The method of claim 1, wherein the output of the compressor is adjusted by a combination of adjustments to pumping speed and displacement of the compressor. 9. A method of producing an oxygen rich gas, comprising: providing ambient air to a compressor; pressuring said ambient air in the compressor; delivering the pressurized air from the compressor to a PSA unit; processing said pressurized air in the PSA unit in accordance with a PSA cycle so as to produce an oxygen rich gas; measuring the pressure of the oxygen rich gas; maintaining the pressure of the oxygen rich gas at one or more pre-selected levels by adjusting an output pressure of the compressor; and measuring an ambient pressure about the substantially enclosed space so as to facilitate adjustment of the output pressure of the compressor when the ambient pressure changes. 10. The method of claim 9, wherein the output pressure of the compressor is adjusted based on a value representative of a combination of the pressure of the oxygen rich gas and the ambient pressure. 11. The method of claim 10, wherein the value comprises a compression ratio that is expressed as K=(Pambient+Paccumulator)/Pambient, where Pambient represents the pressure of the oxygen rich gas and Paccumulator represents the ambient pressure. 12. The method of claim 11, further comprising determining a target value of the oxygen rich gas, P*, based on the value of the compression ratio, such that the output pressure of the compressor is adjusted to provide pressure of the oxygen rich gas at or near the target value. 13. A method of producing an oxygen rich gas, comprising: providing ambient air to a compressor; pressuring said ambient air in the compressor; delivering the pressurized air from the compressor to a PSA unit; processing said pressurized air in the PSA unit in accordance with a PSA cycle so as to produce an oxygen rich gas; measuring the pressure of the oxygen rich gas; maintaining the pressure of the oxygen rich gas at one or more pre-selected levels by adjusting an output pressure of the compressor; and wherein maintaining the pressure of the oxygen rich gas at the one or more pre-selected levels comprises maintaining the pressure within a range of pressure values having a nominal value, wherein the range of pressure values is determined by measuring and logging values of the pressure of the oxygen rich gas during a selected period, so that the range includes a full range of the logged values. 14. The method of claim 13, wherein the nominal value comprises an average of the full range of the logged values. 15. The method of claim 13, wherein the range further includes upper and lower threshold values, so that a pressure value outside of such threshold values triggers the adjustment of the output pressure of the compressor. 16. The method of claim 15, wherein the upper and lower threshold values are determined by deviations from the nominal value by a fraction of the full range. 17. The method of claim 16, wherein the fraction comprises approximately two percent. 18. The method of claim 13, wherein the selected period comprises an initial period of the operation of the compressor. 19. A method of producing an oxygen rich gas, comprising: providing ambient air to a compressor; pressuring said ambient air in the compressor; delivering the pressurized air from the compressor to a PSA unit; processing said pressurized air in the PSA unit in accordance with a PSA cycle so as to produce an oxygen rich gas; measuring the pressure of the oxygen rich gas; maintaining the pressure of the oxygen rich gas at one or more pre-selected levels by adjusting an output pressure of the compressor; monitoring an operating parameter of the compressor that is used for adjusting the output pressure of the compressor; determining whether the operating parameter can be adjusted by an amount greater than a capacity margin associated with the operating parameter of the compressor; and wherein a service indicator is triggered if the amount of adjustment exceeds the capacity margin. 20. The method of claim 19, wherein the further comprising determining whether the operating parameter can be adjusted by an amount greater than a capacity margin associated with the operating parameter of the compressor. 21. The method of claim 19, wherein the operating parameter comprises a speed of a pump used in the compressor. 22. A gas fractionalization apparatus, comprising: a compressor which compresses a gas to provide an output gas; a PSA unit which receives and processes the output gas from the compressor to produce a product gas; a sensing device which measures the pressure of the product gas; and a feedback mechanism which controls the pressure of the product gas by varying one or more parameters of the compressor in response to changes in the pressure of the purified gas; and a second sensing device which measures the pressure of ambient air. 23. The apparatus of claim 22, wherein the product gas comprises an oxygen rich gas. 24. The apparatus of claim 22, wherein the product gas pressure is measured by the sensing device within a storage device. 25. The apparatus of claim 22, wherein the feedback mechanism comprises a programmable controller and a pulse width modulation circuit in communication with the compressor. 26. The apparatus of claim 22, wherein the feedback mechanism adjusts the output pressure of the compressor to maintain a pre-determined compression ratio.