The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 29, 2001
Filed:
Mar. 31, 1998
John William Ernest Brydon, Waverton, AU;
ResMed Limited, New South Wales, AU;
Abstract
Apparatus and methods for the estimation of flow and the detection of breathing (respiration) in continuous positive airway pressure (CPAP) treatment are disclosed. CPAP apparatus typically includes a flow generator for supplying air to a mask via a gas delivery tube. With changing air flow, the flow generator's speed and/or driving electrical current will alter in a manner defined by the controlling circuitry. Signals can be derived from measurements of motor speed and current, and these signals vary cyclically with patient respiration. By filtering to reject non-respiratory components, the resultant signal can be utilized to determine the instants in time at which the patient starts to inhale and exhale. The filtered signal also can be linearized using a predetermined knowledge of the pressure/flow/speed characteristics of the flow generator, and thus to derive a volumetric measure of airflow.