GB843586A - Respiratory device - Google Patents

Abstract

843,586. Respiratory appliances. BENDIX AVIATION CORPORATION. Nov. 14, 1958 [Dec. 13, 1957], No. 36737/58. Class 81(2). A respiratory gas regulating apparatus comprises a container 18 to which respiratory gas is supplied at a rate variable with altitude, the gas stored in the container during user exhalation being conducted to the user, during inhalation, through a chamber 20 having a normally closed valve 37 which opens to admit atmospheric air when the pressure in the passage falls below a selected value relative to ambient atmospheric pressure. Oxygen is supplied continuously at a pressure dependent on altitude, to outlets 13 of a manifold 12, through a pressure control valve 11 comprising an evacuated aneroid 15 and a diaphragm 16 which act to open the valve upon decompression at the aircraft cabin. Each outlet 13 is connected by a hose 28 to an individual regulator and mask assembly. A tube 30 passing through each regulator supplies oxygen continuously to a collapsible bag 18 on inhalation gas is drawn from the bag 18 through the chamber 20 and oxygen inlet holes 47 which are controlled by a valve disc 50 and are disposed in a plate 45 at one end of the chamber, to a mask 32. When the bag collapses air is drawn into the chamber and the mask through air inlet holes 36 which are controlled by a valve disc 37 and are disposed in an air inlet plate 34 at the other end of the chamber on exhalation the oxygen and air inlet holes 47, 36 are closed and exhaled gas passes through exhalation holes 48 controlled by an annular valve 55 into a chamber, formed between the rear 59 of the mask and the chamber, and passes to atmosphere through holes formed between ribs 61 on the interior of the mask rear end and an annular extension 58 of the air inlet plate 34. The valve discs 37, 50 and valve 55 may be made of silicone rubber and other parts of the regulator are made of transparent rigid synthetic plastic. Specification 837,250 is referred to.