Patent GB-432344-A (GB)
Title: Improvements in closed-circuit respiratory apparatus
IPC: A62B9/02
Filed: 1933-10-16
Abstract: 432,344. Valves. HERMAN, S., Mikolow, Poland. Oct. 16, 1933, No. 28606. [A Specification was laid open to inspection under Sect. 91 of the Acts, April 16, 1934]. [Class 135] [See also Group VI] In a closed - circuit respiratory appliance the lung-operated oxygen supply valve comprises an elongated frustoconical piston and the valve and its actuating mechanism is located wholly within or wholly outside the breathing bag. The valve 3 comprises a frusto-conical piston 32 Fig. 2 moving in a cylindrical chamber 37 and having an ebonite or other pad 38 arranged to occlude the oxygen inlet 33. Oxygen passes constantly through a passage 31 and nozzle 31<a>, and also through inlet 33 when open, into a space 34 closed by a diaphragm 35 secured to the piston and the valve casing, and thence through a passage 36. An operating lever 60 passing through a slot in the piston 32 and held between a spring 61 and an adjusting screw 62, is connected to the breathing-bag and lifts the piston on collapse of the bag during inhalation. In the modification shown in Fig. 5 the piston and its cylindrical chamber are carried respectively by a tube 46 and a tube 45 slidable within it, the piston having a spindle passing through a cross-head 46<a> and being pressed by a spring 55. Sheet metal brackets 51, 50 are secured to the walls of the breathing bag 4, each bracket having a pair of side plates formed with slots extending in opposite directions, the slots 52 being straight and the slots 53 having right angle bends as shown. The tubes 45, 46, have cross-pins 49, 48, which are engaged in the slots 53, 52, to secure the valve unit within the breathing bag. Oxygen is supplied by a flexible tube to a nozzle at the upper end of the tube 45 and passes through a sieve and a constricted orifice to the piston chamber. The end of the piston has no pad. In both constructions the piston may comprise a figure of revolution varying slightly from true frusto-conical shape. The Specification as open to inspection under Sect. 91 also comprises the following subjectmatter. A reducing valve 2, Fig. 2 (Cancelled), has a strainer 12 and a pair of concentric tubes 13 constituting a cooler for the gas, leading to a chamber 20 containing a plug 24, the plug having a packing 25 with a conical seating engaging over a conical nozzle 23 in the gas passage. The plug 24 is connected by a spindle 26 with a plug carrying a diaphragm 25<a> the diaphragm having a spring loading adjustable by a screw 29. A passage 16 leads to a manometer and a byepass valve, and a passage 27 to the lung-operated valve. The inhaling and exhaling valves 60, Fig. 12 (Cancelled), each comprise a square or rectangular metal plate hinged at one side by a folded metal plate 61 gripping the plate 60 and enclosing a spindle 62. The plate 60 is pressed upon a frame-seating 59 by a coil spring 65 held by a stirrup 66, and the spindle 62 is journalled in lugs 64 with play at right angles to the plane of the seating to permit complete closure of the valve. This subjectmatter does not appear in the Specification as accepted.