Patent ID: 9615962
Date: 2017-04-11
CPC Classifications: A61F,A61M

Claim:
1. A nasal cannula comprising: a cannula body having a passageway extending therethrough from a first end to a second end; and an airflow restrictor coupled to said cannula body and positioned to selectively restrict air flow through said passageway during inhalation and exhalation, wherein said airflow restrictor provides a greater airflow restriction during said exhalation than during said inhalation, wherein said airflow restrictor is substantially flat when in an at-rest configuration, wherein said airflow restrictor is deformable in a first direction from said at-rest configuration to an inhalation configuration during said inhalation, wherein said airflow restrictor is deformable in a second direction opposite said first direction from said at-rest configuration to an exhalation configuration during said exhalation, and wherein said airflow restrictor exerts a substantially constant backpressure during said exhalation for a predetermined range of expiration flow rate; and a frame extending across said passageway and coupled to said cannula body; wherein said airflow restrictor is coupled to said frame; wherein said frame comprises a plurality of spokes extending substantially diametrically across said passageway; wherein said airflow restrictor rests on said frame when in said at-rest configuration, wherein said airflow restrictor is deformable away from said frame when in said inhalation configuration, and wherein portions of said airflow restrictor are deformable between said spokes when said airflow restrictor is in said exhalation configuration; wherein said portions of said airflow restrictor deformable between said spokes create a peripheral passageway through which air may be expelled in said exhalation configuration.