GB551608A - Improvements in masks for respiratory use and appliances - Google Patents

Abstract

551,608. Respiratory masks. BOOTHBY, W. M., BULBULIAN, A. H., and LOVELACE, W. R. Dec. 8, 1939, No. 31816. Convention date, July 28. [Class 81 (ii)] An oronasal mask for supplying oxygen &c. to the mouth comprises a body of semi-rigid material forming an open-sided chamber 12 which receives the mouth and nose of the wearer, a supply tube 35 extending from the exterior of the lower part of the chamber and connected to and supporting a rebreathing bag 38, and an oxygen supply tube 39 extending into the bag; the body of the mask has bevelled outwardly-extending margins 14 .. 17 which contact the upper part of the nose, the cheeks and the front of the chin and the tube 35 extends downwards and outwards relatively to the front wall of the mask so that, when the mask is worn, the bag 38 tends to bend the tube inwards and so press the lower part of the mask into firm engagement with the chin of the wearer. A stiffening rib 31 may be provided extending transversely of the chamber 12 below the nose-receiving portion and above the mouth receiving portion thereof with a U-shaped rib 33 extending. downwards from the rib 31 and around the lower part of the mask. The fastening straps 24, 25 are connected to a plate 19 secured to the front of the mask and having spring fingers 21, 22 which extend toward the margins of the mask to urge them yieldingly against the soft parts of the face of the wearer. Specification 551,609 is referred to. The Proceedings of the Staff Meetings of the Mayo Clinic 13 (U.S.A.) dated October 12, 1938, and the Journal of Aviation Medicine (U.S.A.) dated December, 1938, are referred to.