Fault diagnosis in CPAP and NIPPV devices
AssigneeResMed Limited
InventorsGregory A. Colla, Barton John Kenyon
Life of this patent
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Abstract
A ventilation device for non-invasive positive pressure ventilation (NIPPV) or continuous positive airway pressure (CPAP) treatment of a patient has a gas flow generator, a gas delivery circuit optionally including a humidifier, a controller and sensors monitoring values of operational parameters of the device. The device further includes one or more relationships stored in data storage of the controller relating combinations of parameter values as being indicative of fault conditions of the device operation, the sensors and/or the fault detection process.
Claims46
A method of detecting a fault in an apparatus for supplying breathable gas to a patient at a positive pressure, the apparatus including a gas flow generator comprising a servo controlled motor and impeller, a motor speed transducer configured to produce a motor speed transducer signal, a motor drive parameter transducer configured to produce a motor drive parameter transducer signal, a pressure transducer configured to produce a pressure signal indicative of the pressure generated by the apparatus, and a flow transducer configured to produce a gas flow signal, the method comprising:
- monitoring the motor speed in connection with the motor speed transducer signal produced by the motor speed transducer;
- monitoring the motor drive in connection with the motor drive parameter transducer signal produced by the motor drive parameter transducer;
- monitoring the pressure in connection with the pressure signal produced by the pressure transducer;
- monitoring the gas flow in connection with the gas flow signal produced by the flow transducer;
- following a predetermined duration, comparing:
- the motor speed to a first threshold to derive a first compared value,
- the motor drive to a second threshold to derive a second compared value,
- the pressure to a third threshold to derive a third compared value, and
- the gas flow to a fourth threshold to derive a fourth compared value;
- and
- determining a speed transducer fault condition in accordance with the first, second, third, and fourth compared values.
A method of operating an apparatus for supplying breathable gas to a patient at a positive pressure, the apparatus including a gas flow generator comprising a servo controlled motor and impeller, a motor speed transducer configured to produce a motor speed transducer signal, a motor drive parameter transducer configured to produce a motor drive parameter transducer signal, a pressure transducer configured to produce a pressure signal indicative of the pressure generated by the apparatus, a flow transducer configured to produce a gas flow signal, and a display, the method comprising:
- determining a speed transducer fault;
- providing a warning notice on the display;
- and
- generating a pressure and attempting to increase the pressure to a predetermined level in a predetermined time period.
An apparatus for supplying breathable gas to a patient at a positive pressure, comprising:
- a gas flow generator comprising a servo controlled motor and impeller;
- a motor speed transducer configured to produce a motor speed transducer signal;
- a motor drive parameter transducer configured to produce a motor drive parameter transducer signal;
- a pressure transducer configured to produce a pressure signal indicative of the pressure generated by the apparatus;
- a flow transducer configured to produce a gas flow signal;
- and
- a controller configured to at least:
- monitor the motor speed in connection with the motor speed transducer signal produced by the motor speed transducer,
- monitor the motor drive in connection with the motor drive parameter transducer signal produced by the motor drive parameter transducer,
- monitor the pressure in connection with the pressure signal produced by the pressure transducer,
- monitor the gas flow in connection with the gas flow signal produced by the flow transducer,
- compare, following a predetermined duration:
- the motor speed to a first threshold to derive a first compared value,
- the motor drive to a second threshold to derive a second compared value,
- the pressure to a third threshold to derive a third compared value, and
- the gas flow to a fourth threshold to derive a fourth compared value, and
- determine a speed transducer fault condition in accordance with the first, second, third, and fourth compared values.
An apparatus for supplying breathable gas to a patient at a positive pressure, comprising:
- a gas flow generator comprising a servo controlled motor and impeller;
- a motor speed transducer configured to produce a motor speed transducer signal;
- a motor drive parameter transducer configured to produce a motor drive parameter transducer signal;
- a pressure transducer configured to produce a pressure signal indicative of the pressure generated by the apparatus;
- a flow transducer configured to produce a gas flow signal;
- a display;
- and
- a controller configured to at least:
- determine a speed transducer fault;
- provide a warning notice on the display;
- and
- generate a pressure and attempt to increase the pressure to a predetermined level in a predetermined time period.
Dependencies are inferred from the claim text.