Oxygen supply system

摘要

981,549. Valves. PURITAN COMPRESSED GAS CORPORATION. Aug. 26, 1963 [Sept. 24, 1962], No. 33644/63. Heading F2V. [Also in Division F4] A valve 16 for controlling supply of liquid oxygen to a container 10 and withdrawal of vapour therefrom and from an ambient airheated vaporizing coil 12 has a chamber 46 provided with an inlet port 22 connected through a line 20 to the gas space of the container 10, an inlet port 24 controlled by a valve member 52 and connected to the upper end of coil 12, an outlet port 26 controlled by a valve member 40 and connected to a supply line 30 and a vent port 28 controlled by a valve member 58; valve member 52 being open only when pressure in chamber 46 is below a first predetermined value, e.g. 75 p.s.i., valve 40 being open only when pressure in chamber 46 is above a second lower predetermined value, e.g. 60 p.s.i., and valve 58 being open when pressure in chamber 46 is above a third and higher predetermined value, e.g. 100 p.s.i. Valve 52 is connected by a stem 60 to valve 58 and is urged against its seat 50 by a spring-loaded rod and piston assembly 70 projecting through an aperture 54 in valve 40 which forms an annular seat 56 for valve 58 and is itself urged to its seat 48 by a spring 36 within the valve housing 23. Valve 40 is supported by a bellows 44 clamped between upper and lower portions of the valve housing 23 and is held by toggle means 64 in the open position shown in Fig. 1 during filling of container 10 through a valve 14. In releasing the toggle to the position shown in Fig. 2 valve 58 closes, valve 52 opens and valve 40 closes sequentially and after build-up of pressure in chamber 46 valve 40 opens against spring 36 and valve 52 remains open thus allowing discharge from both the gas space of the container 10 and from the coil 12. Fall in demand resulting in a pressure rise in chamber 46 to above 75 p.s.i. contracts bellows 44 sufficiently to close valve 50 and a pressure rise to above 100 p.s.i. further contracts bellows 44 to unseat valve 58 and connect chamber 46 to vent port 28.