05540223 is referenced by 197 patents and cites 12 patents.

A flexible, resilient respiratory mask facial seal adapted for confronting engagement with the face of a user to form an annular sealed interface encompassing a predetermined portion of the user's face. The facial seal includes a peripheral wall and an inturned flap seal. The flap seal projects radially inwardly of the peripheral wall and defines a contoured sealing surface adapted for confronting and sealing engagement with the user's face. The flap seal includes a recessed area corresponding substantially in the shape to a human nose for continuously and matingly conforming to the front and side contours of the user's nose when the facial seal is brought into confronting engagement with the user's face. The facial seal may be adapted for attachment to a respiratory mask body or may be removably placeable over the facial seal of an existing respiratory mask.

Title
Respiratory mask facial seal
Application Number
197960
Publication Number
5540223
Application Date
December 9, 1994
Publication Date
July 30, 1996
Inventor
Mary T Walthour
Pitcairn
PA, US
John R Starr
Leechburg
PA, US
Eric W Starr
Pittsburgh
PA, US
Agent
Reed Smith Shaw & McClay
Assignee
Respironics
PA, US
IPC
A62B 18/02
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