VALVE SYSTEM FOR VENTING ANESTHESIA OR ANALGESIA APPARATUS AND THE LIKE AND VALVES THEREFOR

SYSTEME DE SOUPAPES POUR ELIMINER LES GAZ D'ANESTHESIE OU D'ANALGESIE ET SOUPAPES DU MEME GENRE

English Abstract

ABSTRACT OF THE DISCLOSURE
A valve system is provided for venting an anesthesia
apparatus in a room space, such as an operating theatre, to the
atmosphere outside the room, so as to prevent unwanted build-up
of escaping anesthesia gas in the room, together with a venting
valve for that purpose. The venting valve has two inlets, each
with a respective one-way valve, and a single outlet meeting at
an interior junction. Pipe means connect the anesthesia
apparatus to one inlet, and the one-way valves ensure that gas
flows only to the atmosphere. Other pipe means connect the room
interior to the other inlet and again the one-way valves ensure
only flow of gas from the room interior to the atmosphere.
Further pipe means connect the outlet to the exterior
atmosphere. Preferably the one-way valves are flexible
diaphragm valves that are moved by gas movement and pressure
into and out of engagement with rigid diaphragm supports to
respectively close and open the valve.

Claims

The embodiments of the invention in which an exclusive property
or privilege is claimed are defined as follows:
1. A valve system for the venting to the atmosphere
outside a room space of anesthesia apparatus within the room
space comprising:-
vent valve means comprising a valve body having a first
inlet, a second inlet and an outlet all meeting at a junction
within the body;
pipe means for connecting to the first inlet an outlet
of the anesthesia apparatus through which anesthesia gas can
escape into the ambient space;
a first one-way valve at the first inlet permitting
flow of gas from the first inlet to the junction and preventing
reverse flow;
pipe means for connecting the ambient room space to the
second inlet;
a second one-way valve at the second inlet permitting
flow of gas from the second inlet to the junction and preventing
reverse flow; and
pipe means for connecting the outlet to the ambient
atmosphere outside the ambient room space.
2. A valve system as claimed in claim 1, wherein each
one-way valve comprises a flexible diaphragm which is urged into
and out of contact with a rigid diaphragm support for
respectively closing and opening of the valve by pressure and
flow of gas in the respective direction.

3. Vent valve means for the venting to the atmosphere
outside a room space of anesthesia apparatus within the room
space comprising:
a valve body having a first inlet for connection
thereto of pipe means from the anesthesia apparatus, a second
inlet for the connection therein of pipe means from the said
room space, and an outlet for the connection thereto of pipe
means to the said atmosphere, all meeting at a junction within
the body;
a first one-way valve at the first inlet permitting
flow of gas from the first inlet to the junction and preventing
reverse flow; and
a second one-way valve at the second inlet permitting
flow of gas from the second inlet to the junction and preventing
reverse flow.
4. Vent valve means as claimed in claim 3, wherein each
one-way valve means comprises a rigid diaphragm support and a
flexible diaphragm which is urged into and out of contact with
the support for respectively closing and opening of the valve by
pressure and flow of gas in the respective direction.

Description

Valve System for Ventin~ Anesthesia or anal~esia Ap~aratus
and the llke and Valves Therefor
. . . _ _ . =
Field of the Invention
~ --m
The present invention is concerned with a new valve
system for venting anesthesia or analgesia apparatus and the
like, and with a valve for such a system.
Review of the Prior Art
The use of anesthesia or analgesia apparatus or the
likè (hereinafter referred to for brevity as anesthesia
apparatus) is in practice almost exclusively confined to
~ enclosed spaces, such as operating rooms in hospitals and
surgexies. Even if the apparatus is of the rebreathing type it
must include a pressure relief valve, through which at least
some of the anesthetizing gas escapes into the surrounding area
where it can accumulate to an uncomfortable, if not unsafe,
concentration. The possibility of such an accumulation is of
course substantially greater with apparatus of the direct flow
type. To avoid the possibility of such a condition the room
could be vented to atmosphere, but this again can be
complicated, for example, in the case of an operating room
requiring close control of ambient temperature and the
maintenance at all times of maximum sterility, even when the
outside temperature varies through the normal range of about
-30 to 35C.

~2~ 4
Definition of the Invention
It is therefore an object of the invention to provide a
new valve system for venting anesthesia apparatus permitting
venting of the apparatus to the exterior of the room in which it
is accommodated.
It is also an object to provide a new venting valve for
use in such a valve system.
In accordance with the present invention there is
provided a valve system for the venting to the atmosphere
outside a room space of anesthesia apparatus within the room
space comprising:
vent valve means comprising a valve body having a first
inlet, a second inlet and an outlet all meeting at a junction
within the body;
pipe means for connecting to the first inlet an outlet
of the anesthesia apparatus through which anesthesia gas can
escape into the ambient space;
a first one-way valve at the first inlet permitting
flow of gas from the first inlet to the junction and preventing
reverse flow;
pipe means for connecting the ambient room space to the
second inlet;
a second one--way valve at the second inlet permitting
flow of gas from the second inlet to the junction and preventing
reverse flow; and
pip2 means for connecting the outlet to the ambient
atmosphere outside the ambient room space.

3~
Also in accordance with the invention there is provided
a vent valve means for the venting to the atmosphere outside a
room space of ane~thesia apparatus within the room space
comprising:
a valve body having a first inlet for connection
ther~to of pipe means from the anesthesia apparatus, a second
inlet for the connection therein of pipe means from the said
room space, and an outlet for the connection thereto of pipe
means to the said atmosphere, all meeting at a junction within
the body;
- a first one-way valve at the first inlet permitting
flow of gas from the first inlet to the junction and preventing
reverse flow; and
a second one-way valve at the second inlet permitting
flow of gas from the second inLet to the junction and preventing
reverse flow.
escri~tion of the Drawings
A valve system for venting anesthesia apparatus and a
venting valve therefor which are particular preferred
embodiments of the invention will now be described, by way of
example, with reference to the accompanying diagrammatic
drawing, wherein:-
FIGVRE 1 is a general perspective view of an anesthes;a
apparatus illustrating the manner of use therewith of a valve
system of the invention;
FIGURE 2 is a similar view to a larger scale of the
valve used in the system illustrated by Figure 1, parts being
shown broken away as necessary for the interior to be seen; and

~z9 ~3~4
FIGURES 3 and 4 are respectively plane cross sections
~aken on the lines 3-3 and 4-4 of Figure 2.
Description of the Preferred Embodiments
_
The anesthesia apparatus with which the valve system of
the invention is used can be of any type, either rebreathing or
direct, although a rebreathing type apparatus is illustrated and
is indicated by the general reference 10. The apparatus
includes as an integral component thereof a relief valve 12
which, in the absence of the valve system invention would vent
directly into the surrounding room space. However, a direct
- vent to the outside atmosphere would cause difficulty because of
the variation encountered in outside tempPratures and pressures
with weather changes, resulting in the possibility of lack of
adequate venting and inflow of outside air to a space which is
required to be kept sterile and at a stable temperature.
In accordance with the invention therefore the
apparatus 10 is vented to pipe means 14 from the valve 12 (or
from its equivalent from which anesthetic gas may escape into
the room), which pipe means connects the valve 12 to a first
apparatus inlet 16 of a relief control valve 18 of the
invention. Another pipe means 20 leads from one or more
convenient locations in the room to a second room inlet 22 of
the valve, the downstream side of which is connected at a
junction 24 to the downstream side of the first inlet 16. The
junction 24 is connected via pipe means 26 to any convenient
point of the outside atmosphere.
-- 4--

~2~3~
The inlet-16 is provided inside the valve body with a
respective one-way valve 28 that will open automatically upon
appliction of pressure and flow from the relief valve 12 (arrow
30), but will close and prevent reverse flow upon application of
S pressure and flow from the junction, and thus from the second
inlet 22 and the outlet to the pipe 26 (arrow 32). Such a valve
consists of a rigid flow through diaphragm brace or support 34
(see also Figure 3), mounted in the inlet 16 and.supporting when
the valve is fully closed a flexible valve diaphragm 36 (see
also Figure 4) that is moved toward and away from the support by
pressure and flow of gas in the respective direction. The inlet
22 is provided with a respective similar one-way valve 38, which
will close with pressure and flow from the junction, and thus
from the atmosphere or inlet 16 (arrow 40), but will open with
pressure and flow from the room interior (arrow 42).
Anesthesia gas escaping from the apparatus can
therefore pass to the outside atmosphere without the possibility
of entering the room, or of the room air and outside air
reaching the apparatus interior. Similarly, if the room air
pressure becomes substantially higher than that of the outside
atmosphere relief is obtained by automatic opening of the valve
38 without the possibility of that air returning to the
apparatus~ Increase in.the outside pressure will no~ permit any
outside air to enter ~ither the room or the apparatus.
It wiLl be seen therefore that I have provided a simple
but effective valve system for venting anesthetic apparatus from
the room in which it is located which, because of the mechanical
simplicity of the valve which it employs, is also highly
reliable.