GB501138A - Improvements in or relating to gas-dispensing apparatus, especially for aircraft - Google Patents

Abstract

501,138. Respiratory appliances; valves. BRONZAVIA SOC. ANON. Aug. 23,1937, No. 23107. Convention date, Nov. 6,.1936. [Class 135] [Also in Group VI] Apparatus, especially adapted for dispensing oxygen to aviators in amounts depending on the pressure of the ambient medium, comprises a valve actuated by a barometric device. Means are provided for regulating the change of shape of the barometric device in such a manner that the valve is not opened until the pressure of the ambient medium has fallen to a predetermined figure and thereafter the valve is first rapidly opened with decreasing ambient pressure until a second predetermined pressure is reached, after which the valve is further opened but at a slower rate. In the form shown in Fig. 1, the gas valve 6 is actuated by a diaphragm 8 subject. to the pressure in the outlet chamber 1 and a comparatively stiff barometric capsule 4. Opening of the valve is delayed by a spring 9 acting on the valve spindle 5 through a lever 10. When the valve commences to open, the outlet pressure is communicated through a pipe 14 to a chamber 13 where it acts on a bellows 12 coupled to the lever to counteract the force of the spring and ultimately put it out of action. In the form shown in Fig. 2, a flexible capsule 4' and a stiff capsule 4<2> are coupled in series with the free face of the capsule 4<2> spaced apart from the end of the spindle 5 at ground level. As the ambient pressure falls the lost motion is first taken up and then both capsules act to open the valve until at a certain pressure the movable end of the more flexible bellows engages a fixed stop 15, after which the stiffer bellows alone is operative. In another modification an elastic bellows is adapted to engage an opposing spring after expanding a predetermined amount. In order that the volume of oxygen delivered at varying altitudes may more nearly follow a straight line, an additional loading spring may be fitted adapted first to oppose the opening of the valve and afterwards assist the opening of the valve. To compensate for temperature the spindle 5 may be divided and the parts coupled together by a thermo-responsive member. The Specification, as open to inspection under Sect. 91 describes an oxygen-supply installation for several members of the crew of an aircraft comprising a closed pipe circuit with safety cut-off valves, consisting of ball valves held in the neutral position by springs, at each tapping point. In other distributing systems alternative supplies are made available to suit the varying exertions of the various members of the crew. In one form the outlet chamber 1 is connected to a pair of chambers from each of which pipes with calibrated orifices of differing size lead to each supply point. In the system shown in Fig. 9 (Cancelled), each supply point 28 is coupled to three distributing chambers 27 supplied through three regulators 1<1>, 1<2>, 1<3>. The regulators 1<2>, 1<3> are supervised by the regulator 1<1>. This subject-matter does not appear in the Specification as accepted.