| 摘要 |
A nasal mask has a shell portion that is a hollow enclosure with a rearwardly facing opening that is defined by edge portions of the shell portion. A resiliently deformable endless interface member engages and extends around the edge portion of the opening and forms a seal between the shell portion and the user's face. The shell portion and the interface member are generally symmetrical about a median place. The shell portion has two gas inlet orifices, one on each side of the median place. The shell portion has a tubular exhalation outlet extending from the face of the mask. The mask is further provided with a balloon exhalation valve connected to the exhalation outlet for alternately venting and sealing the interior of the mask during exhalation and inhalation, respectively. |
