GB761263A - Improvements in respiratory masks - Google Patents

Abstract

761,263. Respiratory apparatus. MARTINDALE ELECTRIC CO., Ltd. Jan. 31, 1955 [Feb. 22, 1954], No. 5093/54. Class 81(2) A respiratory mask which fits over the nose and mouth of the wearer is formed of flexible plastic material having a deformable non- resilient metal element moulded into the plastic material around the whole of its peripheral edge to enable the edge of the mask to be bent to conform to the contours of the wearer's face and retained in the form into which it is bent. The mask is in the form of an isosceles triangle in vertical cross-section, is made of polythene and its edge 7 is provided with a bead 6 in which a helical wire 8 of deformable resilient metal is embedded. Disc-type non-return expiratory valves 10 are provided. A filter container 12 in the form of an equilateral triangle with the apex uppermost is made integral with the mask and is provided with a perforated lid 13. Ribs 15, 17, formed inside and integral with the rear wall of the filter container 12 and the lid 13 respectively, form, between them and the faces of a filter pad (not shown), passages by which air can pass readily to the filter pad and thence to an inspiratory opening 11 controlled by a non-return valve 11a. In a modification, the filter container is detachable from the mask, a complementary socket and recess being provided in the filter container and the mask respectively. Alternatively the mask may be connected to a separate filter unit by a flexible tube. The mask may be used without a filter unit for the administration of anµsthetics. According to the Provisional Specification, the ends of the wire may project slightly from the edge of the mask to hold a detachable fabric covering against the mouth of the mask.