GB488632A - Improved apparatus for protection against gases - Google Patents

Abstract

488,632. Respiratory apparatus; pipe joints. BOURGEOIS, A. Oct. 2, 1936, No. 26806. Void. Convention date, Oct. 2, 1935. [Class 81 (ii)] [Also in Group XXVIII] In closed-circuit breathing - apparatus, in which air is exhaled from a pipe 20, Fig. 2, through an exhaling valve 19a and a carbon dioxide absorbent canister 13 into a breathing bag 12 and is inhaled from the bag directly through a pipe 16 and inhaling valve 18a, replacement of the canister 13 without opening the apparatus to atmosphere is permitted by the provision of a byepass pipe 17 and three-way cocks 14, 15. The apparatus is enclosed in a casing 1 having shoulder straps and a belt 3, and a hinged lid covering the canister and adjacent parts. The bag 12 has connections 7 for two oxygen cylinders 4 secured to casing 1 by rings 5 and to the connections 7 by fly-nuts 6. Spring-pressed valves 27 in the connections close the apparatus during replacement of the cylinders. The cylinder fittings may include regulatable pressurereducing valves and manometers. The canister 13 is connected by quick-release means comprising collars 22, Figs. 2 and 5, rotatable on flanged ends of the connecting pipes 14c, 15c, by levers 23, and each carrying two oppositelydisposed part-circular flanges 24. With the levers. 23 positioned as in Fig. 5, segmental undercut guides 21 on the canister may be slid laterally on to the connecting-pipes 14c, 15c, guided by bevelled plates 31 and positioned against depending stop-pieces 31a ; rotation of levers 23 to the left (as shown) then engages flanges 24 in the undercut grooves 21a of parts 21. The interengaging parts are formed with cam faces, as 24a, producing a tight joint. The cocks 14, 15, Fig. 2, are simultaneously operated by links connected to their levers 14f, 15f and extending through one side of the casing, the links being connected by a crosspiece normally secured to the casing 1 by a latching device. The levers 14f, 15f lie in front, and prevent movement of the levers 23 until after the cocks 14, 15, have been turned to cut out the canister and insert the pipe 17 in the breathing circuit. For subaqueous use the hinged lid of the casing 1 and the canisterreplacement features are dispensed with.