Patent ID: 7891354

Claim:
A breathing assistance system having active noise control, the system comprising: a gas delivery system operable to supply breathing gas; a patient interface configured to interface with a patient for delivering breathing gas to one or more breathing passages of the patient; a connection system configured to communicate breathing gas supplied by the gas delivery system to the patient interface for delivery to the patient; and a noise control system configured to control noise caused by a noise source associated with the breathing assistance system, the noise control system including: a processor configured to generate noise control signals for at least partially canceling noise caused by the noise source; controller configured to: generate noise source control signals for controlling the operation of the noise source; and communicate the noise source control signals to the processor; a speaker operable to output the noise control signals generated by the processor for at least partially canceling noise caused by the noise source; and a feedback sensor configured to detect noise caused by the noise source and noise control signals output by the speaker, and communicate to the processor feedback noise signals based on the detected noise; wherein the processor is configured to generate the noise control signals based at least on the noise source control signals from the controller and the feedback noise signals from the feedback sensor.