| 摘要 |
<p>846,651. Respiratory appliances. FABIAN, L.W., and NEWTON, G.W. Nov. 27, 1958 [Dec. 16, 1957], No. 38310/58. Class 81 (2). A valve assembly for mounting on top of a liquid anaesthetic container is arranged to pass an adjustable proportion of inhaled air or gas through the container. The slide of the assembly is a rectangular bar 10, Fig. 5, with a central aperture 13 and having a rack 15 in its upper surface so that it can be adjusted by a pinion on a control spindle. The slide is mounted in a guideway 11, Fig. 4, in a body 4 in such a way as to separate the compartments a, b, c, d. With the slide in the position shown the port 13 allows communication between chambers a and c. Inhaled air enters the conduit 6 in the direction of the arrow and passes into chamber a, whence it passes through to chamber b and out to the face mask through conduit 7. If the slide is pushed to the further end of the guide, the aperture 13 provides communication between chambers a and b but a is sealed off from c. However c communicates with d around the end of the slide. Under these conditions air entering chamber a from inlet 6 passes to chamber b and thence through duct 8 into the anaesthetic container. It returns from the container through duct 9 to chamber d and so passes through chamber c to the outlet 7. Intermediate positions of the slide cause corresponding proportions of the air to be passed through the container. A modified form of valve, using a T- shaped slide, is described with reference to Figs. 7 and 8 (not shown).</p> |
