O2 concentrator with sieve bed bypass and control method thereof

Inventors

Westfall, Tom • Brambilla, Enrico

Assignees

Breathe Technologies Inc

Abstract

An oxygen concentrator includes one or more adsorbent sieve beds operable to remove nitrogen from air to produce concentrated oxygen gas at respective outlets thereof, a product tank fluidly coupled to the respective outlets of the sieve bed(s), a compressor operable to pressurize ambient air, one or more sieve bed flow paths from the compressor to respective inlets of the sieve bed(s), a bypass flow path from the compressor to the product tank that bypasses the sieve bed(s), and a valve unit operable to selectively allow flow of pressurized ambient air from the compressor along the one or more sieve bed flow paths and along the bypass flow path in response to a control signal. The valve unit may be controlled in response to a command issued by a ventilator based on a calculated or estimated total flow of gas and entrained air or % FiO2 of a patient.

Core Innovation

A ventilator determines total flow of ventilator gas delivered to a patient by combining measured nozzle flow with measured patient-interface airway pressure, including entrained ambient air. The ventilator uses nozzle-geometry constants and/or pre-stored characteristic curves, such as characteristic %FiO2 or total-flow versus pressure data, to estimate total flow and transmit signals for real-time adjustment.

A PSA oxygen concentrator is operated with one or more sieve beds and a bypass flow path in which pressurized ambient air bypasses the sieve beds and is mixed with nitrogen removal output. The bypass flow is selectively set using a valve unit that can include ON/OFF or proportional valve operation, optionally with a dedicated bypass compressor.

Modular oxygen concentrator system examples are described with detachable oxygen concentrator hardware and external or bypass compressors, and valve timing can be intentionally sub-optimal to adjust oxygen concentration and flow at the product tank. A controller generates a control signal for setting the oxygen concentration in a product tank based on the ventilator master controller signal.

Claims Coverage

The independent claims define ventilator-side determination of total flow of ventilator gas delivered to a patient, including entrained ambient air, using measured nozzle-expelled flow and measured pressure, and then controlling an oxygen concentrator based on that determined total flow. The independent claims cover five main inventive features: total-flow determination from nozzle flow and interface pressure, nozzle-geometry parameterization using stored constants, oxygen concentrator control via transmitted signal, a ventilator control program storage medium, and a ventilator with flow and pressure sensors.

Across the independent claims, the inventive coverage focuses on determining total ventilator gas flow including entrained ambient air by combining measured nozzle-expelled flow with measured patient-interface pressure, and on using that determined total flow to control an oxygen concentrator through transmitted signals, implemented via sensor-equipped ventilator circuitry or computer-executable program instructions.

Stated Advantages

Documented Applications