Patent GB-553880-A (GB)
Title: Improvements in or relating to oxygen regulators
IPC: A62B9/02
Filed: 1941-12-05
Abstract: 553,880. Valves. BENDIX AVIATON CORPORATION. Dec. 5, 1941, No. 15739. Convention date, Dec. 26, 1940. [Class 135] A valve device for controlling the flow of oxygen to a mouthpiece or face mask comprises a first chamber B for automatically receiving and maintaining gas at a predetermined pressure and a second chamber A which is automatically replenished with gas from the first chamber when the pressure of the gas present in the second chamber falls below a predetermined amount. In the form shown in the Figures the two chambers are formed in a member 24 housed in an outer casing 10 formed with a mounting flange 11. This casing has a window 13 through which a pressure gauge 15 connected to the oxygen supply can be seen and fitted with a plate containing instructions for use. An inlet fitting 31 is secured to the chamber B of the member 24 by flanges 30, 32 and bolts 33. This fitting houses a filter 36a held in place by screwed ferrules 36 and a steel valve seat 40 secured in position by a screwed sleeve 41. A valve member 45 of thermo plastic material is pivotally connected to a plunger 42 having guide projections 46 engaging the sleeve and an adjustable abutment 47. The actuating member comprises an aneroid capsule 52 secured to a boss 49 on the member 24 by a screwed shank 51, nut 51a and packing 53. The capsule has a spindle 61 formed with a groove 62 engaging a pin connecting a pair of bifurcated toggle links 58, 66. The link 58 is mounted on a pin 57 supported by upstanding plates 54, 55 secured by pins 56 to the inlet fitting. The link 66 has a recessed part 66a engaging the adjustable abutment 47 and a pin 67 passing through slots 68 in the plates 54, 55. Reduced pressure from the chamber B through a passage 77, annular groove 76, to a chamber 107 below a valve 82 and when the valve is open to the chamber A and thence through a passage 113 to a mouthpiece or facemask. The valve 82 which co-operates with a seat 79 screwed in a fitting 71 secured in the side of the chamber comprises a washer 83 of neoprene supported by a disc 82 secured to a spindle 81. The spindle slides in a guide 80 on the seat member and is provided with an adiustable abutment 85. The chamber A is closed by a diaphragm 29 secured to a spindle 96 provided with two pins 99, 100. The pin 99 forms the centre pivot of a pair of bifurcated toggle links 95, 102 and is journalled in a yoke member 90, A pin 89 passes through the free ends of the link 95 and yoke 90 and slidably engages slots 87a in the ends of supports 81, 88 secured to the fitting 71. A pin 104 passes through the outer end of the link 100 and slots 105 in the lower part of the yoke and is journalled in the supports 87, 88. The mass of the diaphragm is counterbalanced by a weight arm 111 pivoted on a rod 111a and engaging the spindle 96. Suction in the chamber A turns the link 102 about the pivot 104 turning and depressing the link 95 to depress the yoke 90 to depress the valve spindle and open the valve 82 against the action of a spring 86 and the pressure in the chamber 107. The pin 100 engages the link 95 when the valve is closed to prevent the toggle-links passing to the other side of the dead centre and re-opening the valve. A byepass between the chamber B and the passage 113 is controlled by a manually actuated valve 120 co-operating with a removable seat 119. The valve 120 is resiliently pressed to its seat by a spring 122 housed in a hollow screwed spindle 117 having an actuating handle 115 clamped to the end of the spindle by a transverse bolt 116.