GB1503261A - Evaporater - Google Patents

Abstract

1503261 Anaesthetic evaporator for respirators DRAGERWERK AG 10 Feb 1976 [20 Feb 1975] 05208/76 Heading A5T An anaesthetic evaporator for a respirator consists of a gas inlet 11 which divides into an evaporator chamber duct 5 and a by-pass duct 4, the two flows of the gas meeting at a junction 27 before passing to an outlet; wherein the by-pass gas path includes a regulating gap 28 formed between the facing coaxial annular surfaces of a ring 31 and a sleeve 33, the sleeve being located in a hollow, coaxial annular member 18 of higher coefficient of thermal expansion and the ring being supported by screw bolts which freely pass through bores in a housing 2 of height coefficient of thermal expansion, the arrangement being such that temperature changes are compensated for, and the gap can be altered manually using the screw bolts. A seal 37 on the upper surface of the ring directs the gas flow through the gap 28 and the sleeve is fixed to a bottom wall of the member 18 by bolts 34. The gas reaches junction 27 via duct 29. The evaporator chamber gas passes both through and around a helically coiled wick 12 in contact with a cylindrical wick 15 which reaches into the anaesthetic 7, the mixture of gas and anaesthetic from the anaesthetic chamber 6 passing up through a path 19 to a frusto-conical regulating gap 23 varied by vertical movement of a cone 20 using a hand wheel 24. The cone is non-rotatable by virtue of a keying pin 25 and the mixture meets the by-pass gas at junction 27 in a duct leading from an annular duct at the top of the regulating gap.