Abstract: A multi-chamber canister for a pressure swing absorption system within a general housing assembly. The chambers include a first molecular sieve chamber for receiving a first molecular sieve for separating air from the ambient environment into a concentrated gas and at least a second molecular sieve chamber disposed within the housing assembly for receiving a second molecular sieve for separating air from the ambient environment into a concentrated gas component. Furthermore, a supply chamber is disposed within the housing for receiving air from the ambient environment and for communicating air to either first or second molecular sieve chambers.

Abstract: A pressure support ventilatory assist device is disclosed. Pressure is provided by a blower which is operated at the minimum speed necessary to achieve the desired inspiration pressure. Pressure regulation is achieved by means of a novel pressure regulator valve, rather than by modulating blower speed, thereby reducing perceptible noise. The flow sensor is removed from its conventional location between the regulator valve and the patient mask to a location upstream of the regulator valve to minimize resistance to patient expiration and to isolate the valve from possible fluids in the tubing. Since the flow sensor in this location cannot sense expiration flows, the device includes circuitry for generating a model of the expiratory waveform based upon the inspiratory waveform. Actual pressure is then modulated to conform to the model waveform.

Abstract: A pressure support ventilatory assist device is disclosed. Pressure is provided by a blower which is operated at the minimum speed necessary to achieve the desired inspiration pressure. Pressure regulation is achieved by means of a novel pressure regulator valve, rather than by modulating blower speed, thereby reducing perceptible noise. The flow sensor is removed from its conventional location between the regulator valve and the patient mask to a location upstream of the regulator valve to minimize resistance to patient expiration and to isolate the valve from possible fluids in the tubing. Since the flow sensor in this location cannot sense expiration flows, the device includes circuitry for generating a model of the expiratory waveform based upon the inspiratory waveform. Actual pressure is then modulated to conform to the model waveform.

Abstract: A bead thermistor air flow sensor assembly comprising bead thermistor and circuit conductor completely encapsulated between upper and lower layers of thin plastic film. The thermistors are mounted adjacent the outer ends of arms adapted to be aligned with the nostrils and mouth of the patient when the sensor assembly is positioned on the face of the patient by double faced mounting tape. The electrical circuit and bead thermistors being fully encapsulated and sealed, the assembly can be immersed in fluid for sterilization between uses. The assembly is thin and very flexible, permitting either face thereof to be applied to the patient to facilitate connection to monitoring equipment which may include an alarm to signal when normal breathing is interrupted.