Flow path fault detection method for a respiratory assistance apparatus
AssigneeFisher & Paykel Healthcare Limited
InventorsKevin Peter O'Donnell, John Han, Jack Che-Wei Hsu, Samuel Robertson Frame, Grant Martin Dover
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Abstract
A respiratory assistance apparatus is configured to provide a heated and humidified glow of gases and has a control system that is configured to detect a fault in the flow path. A flow path is provided for a gases stream through the apparatus from a gas inlet through a blower unit and humidification unit to a gases outlet. A flow rate sensor is provided in the flow path and is configured to sense the flow rate and generate an flow rate signal and/or a motor speed sensor is provided that is configured to sense the motor speed of the blower unit and generate an indicative motor speed signal.
Claims6
A method for detecting a fault in a flow path of a respiratory assistance apparatus, the flow path comprising a motor-driven blower unit that is configured to generate a flow of gases and which is connected to a humidification unit that is configured to heat and humidify the flow of gases, comprising:
- determining the motor speed of the blower unit required to generate a first set flow rate in the flow path;
- detecting that a motor speed falls below a stored first threshold at the first set flow rate;
- increasing the flow rate to a higher second set flow rate when the motor speed falls below the first threshold;
- determining the motor speed of the blower unit required to generate the second set flow rate in the flow path;
- and
- detecting that the motor speed falls below a stored second threshold at the second set flow rate and generating a fault detection signal when the motor speed at the second set flow rate falls below the stored second threshold.
Dependencies are inferred from the claim text.