U.S. patent number 3,794,072 [Application Number 05/266,226] was granted by the patent office on 1974-02-26 for oxygen diluter device.
This patent grant is currently assigned to Hudson Oxygen Therapy Sales Company. Invention is credited to Donald F. Diedrich, John H. Price.
United States Patent |
3,794,072 |
Diedrich , et al. |
February 26, 1974 |
OXYGEN DILUTER DEVICE
Abstract
An improved device for controlling oxygen concentration
delivered to an oxygen mask comprises a nozzle portion disposed at
one end for attaching an oxygen delivery tube, a hollow gas
delivery portion at the opposite end for directing gas to an oxygen
mask and a tunnel portion disposed between the nozzle and gas
delivery portion having support bars extending between the nozzle
and delivery portions and a plurality of spaced arcuate ribs
secured along the bars between which ribs are defined a plurality
of air entrainment ports through which atmospheric air is drawn for
diluting a stream of oxygen passing along the tunnel. Air
restriction closure members are secured between the ribs
selectively closing one or more of the ports for metering air
entrainment and oxygen concentration delivered to the mask.
Inventors: |
Diedrich; Donald F. (Temecula,
CA), Price; John H. (La Jolla, CA) |
Assignee: |
Hudson Oxygen Therapy Sales
Company (Temecula, CA)
|
Family
ID: |
23013699 |
Appl.
No.: |
05/266,226 |
Filed: |
June 26, 1972 |
Current U.S.
Class: |
137/893;
128/205.11 |
Current CPC
Class: |
A61M
16/06 (20130101); A61M 16/127 (20140204); A61M
16/12 (20130101); A61M 16/0683 (20130101); Y10T
137/87627 (20150401) |
Current International
Class: |
A61M
16/06 (20060101); A61M 16/10 (20060101); A61M
16/12 (20060101); F16k 015/00 () |
Field of
Search: |
;128/209,210,197,205,185,194,145R,145.5-145.8 ;137/604
;239/427.3,428.5,419.5 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Gaudet; Richard A.
Assistant Examiner: Cohen; Lee S.
Attorney, Agent or Firm: Seiler; Jerry R.
Claims
I claim:
1. A device for diluting an oxygen stream delivered to a patient
comprising:
a. a nozzle portion disposed at one end for attaching an oxygen
supply tube;
b. a hollow gas delivery portion at the opposite end for directing
gas to the patient;
c. a hollow tunnel portion extending between the nozzle and gas
delivery portions including a pair of oppositely disposed rods
extending between said nozzle and gas delivery portions and a
plurality of arcuate and parallel ribs secured around both sides of
said rods and spaced therealong whereby a tunnel is defined
interiorly of said ribs and rods and a plurality of ports are
defined between said ribs; and
d. a closure member for each port for being selectively secured on
said device to close at least a portion of a respective port
whereby an oxygen stream flowing through the tunnel portion is
mixed and diluted with entrained air entering through one or more
open ports.
2. The device of claim 1 wherein said closure members comprise air
restriction discs each of which is shaped to substantially occlude
one of said ports.
3. The device of claim 1 wherein said nozzle portion includes a
restricted passageway for creating a high velocity oxygen stream
directed into said tunnel portion.
4. The device of claim 3 wherein said device has three of said
ports and closure members and wherein with all three of said
closure members secured an oxygen concentration of about 40 percent
is delivered at a flow rate of 8 liters per minute, with two of
said closure members secured an oxygen concentration of about 35
percent is delivered at 8 liters per minute flow, with one of said
closure members secured an oxygen concentration of about 28 percent
is delivered at 4 liters per minute flow, and with no closure
members secured and all ports open an oxygen concentration of about
24 percent is delivered at 4 liters per minute flow.
Description
BACKGROUND OF THE INVENTION
A number of devices for diluting the concentration of oxygen
supplied to patients receiving inhalation therapy have been
proposed. Such prior art devices usually include a nozzle for
securing an oxygen supply tube and an enlarged apertured venturi
tunnel portion into which the oxygen is directed from the nozzle.
Normally, large bore tubing is attached between the apertured
venturi portion and an oxygen mask secured on a patient for
delivery of the oxygen enriched gas.
As the high flow of oxygen passes from the nozzle into the enlarged
tunnel, a partial vacuum in the vicinity of the oxygen stream is
created which stream becomes entrained and diluted with room air
drawn through the orifices. The problem with such prior art diluter
devices is that the orifices communicating between the venturi
chamber and room atmosphere supply only a single oxygen dilution
ratio at a specified oxygen flow rate. However, for different
patients, different dilutions may be desired to provide different
oxygen concentrations, for example, 24, 28, 35 and 40 percent with
each of these concentrations requiring separate units having
different sized orifices in order to achieve different dilutions.
In other words, since one unit will provide only a single oxygen
concentration, to have a range of diluters on hand, four separate
units must be purchased, obviously increasing costs and storage and
handling requirements. Moreover, even though the diluters are
intended as disposable units to avoid contamination from patient to
patient, where a single patient requires differing oxygen
concentrations, it will be necessary to provide different
individual diluters.
SUMMARY OF THE INVENTION
It is to the elimination of the above noted disadvantages that the
present invention is directed. The device incorporates an improved
dilution chamber which can be altered to give the full range of
usual oxygen concentrations required for most patients. The device,
intended to be used in combination with an oxygen mask includes a
nozzle portion for securing an oxygen delivery tube. Extending from
one end of the nozzle, opposite the end for attaching the oxygen
delivery tube, is a gas metering tunnel portion comprising a
plurality of spaced arcuate ribs between which ribs are defined a
plurality of dilution ports. The ribs are attached to and suspended
between a pair of oppositely disposed bars or rods which bars are
attached between the nozzle portion and a hollow gas delivery
portion the latter which directs the diluted oxygen to an oxygen
mask. The device also includes a plurality of closure members for
selectively closing one or more of the air entrainment ports as
desired for varying the amount of entrained atmospheric air
entering the mixing chamber and concomitantly the oxygen
concentration delivered to the patient. The closure members may be
inserted or removed as desired so that the varying oxygen
concentrations may be achieved with a single device without the
requirement of utilizing separate diluter devices to achieve
differing oxygen concentrations as has been necessitated by prior
art devices known heretofore.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an enlarged perspective view of the device of the
invention;
FIG. 2 is a top plan view of the device shown in FIG. 1;
FIG. 3 is a front elevational view of the device of FIG. 1;
FIG. 4 is a front elevational view of closure members;
FIG. 5 is a side sectional view of the device;
FIG. 6 is a side elevational view of the device showing a first
closure member inserted;
FIG. 7 is a side elevational view of the device showing first and
second closure members inserted;
FIG. 8 is a side elevational view of the device showing all three
closure members inserted;
FIG. 9 is a front elevational view with all closure members
inserted; and
FIG. 10 is a perspective view illustrating the device as normally
used in combination with an oxygen mask and tubing.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, there is shown an oxygen dilution device 10 of
the invention having a forward end nozzle portion 12 and a
rearwardly disposed gas delivery portion 22. Intermediate between
these two portions is a gas metering tunnel portion 26 through
which an oxygen stream flows from the nozzle portion to the gas
delivery portion.
Referring also to FIGS. 2 and 5, gas metering tunnel portion 26 is
defined between rods 19 and 20, which are disposed on each side of
the tunnel portion, and between arcuate ribs 14, 16 and 18. Each of
the arcuate ribs extend circumferentially around tunnel portion 26
and are secured to both rods 19 and 20. It will be noted that the
ribs are substantially parallel and lie substantially normal to the
central axis of tunnel portion 26 and along which axis gas flowing
between nozzle portion 12 and gas delivery portion 22 travels.
Between adjacent ribs and rib 18 and the gas delivery portion are
defined a plurality of ports 13, 15 and 17 through which ports
atmospheric air is directed for entrainment with and dilution of
oxygen flowing through tunnel portion 26.
Hollow nozzle portion 12 provides a conduit through which oxygen is
directed. The size or diameter of the hollow interior of the nozzle
portion is not particularly critical. However, as shown in FIG. 5,
preferably before communicating with tunnel portion 26, the nozzle
portion interior includes a restricted or relatively narrow
passageway 24. Accordingly, gas flowing through the passageway 24
and entering tunnel portion 26 will be in the form of a high
velocity stream the effect of which stream, entering the
significantly larger diameter tunnel portion 26, causes a partial
vacuum. According to the venturi principle, atmospheric gas in the
immediate vicinity of the tunnel portion will be entrained through
open ports 13, 15 and 17 to combine with the oxygen stream and
thereby dilute its concentration. Thereafter, the diluted oxygen
stream travels through hollow gas delivery portion 22 and exits
through open end 28. With two or more ports open, the air
entrainment effect may actually be described as a cascading venturi
principle since dilution of the oxygen stream passing along the
tunnel portion is carried out in successive stages from one port to
the next.
Exteriorly disposed on the forward end of nozzle portion 12 are a
plurality of frustoconical segments 21 for securing an oxygen
supply tube. Preferably, the first end segment has a smaller
maximum diameter than the adjacent segment so that the segments
have maximum diameters increasing from forward to rear and provide
an adaptor for attaching oxygen tubing of varying sizes. However,
such features are not critical and are merely for convenience.
Hollow gas delivery portion 22 is preferably annular so that the
circumferential exterior thereof may be easily fitted into a
circular receiving orifice of an oxygen mask or large bore tubing
end for delivery of oxygen. A flange 25 is preferably located
around the outer gas delivery portion surface to act as as a stop
for limiting the extent to which the device extends within tubing
or mask opening or orifice. Other equivalent means may be used for
that purpose. However, it should also be appreciated that the
exterior shape as well as the hollow interior of gas delivery
portion 22 is not particularly critical so long as it can be
received and secured with an oxygen mask or tubing to form a
substantially gas tight seal at the receiving orifice as will be
appreciated by those skilled in the art.
Observing also FIG. 4, a plurality of air restricting closure
members 32, 34 and 36 are used for closing gas entrainment ports
13, 15 and 17 (FIG. 2) in order to achieve varying oxygen
concentrations as required. The closure members are preferably in
the shape of a disc corresponding to the arcuately shaped ribs 14,
16 and 18 but which discs have a larger or greater outside diameter
so that they may be relatively easily grasped by an operator for
removal or insertion along tunnel portion 26. The center area of
each of the discs is also hollow and preferably does not interfere
or project into the interior of tunnel portion 26 to avoid
deflection of the air stream passing therealong. The disc centers
are also preferably axially aligned along the central axis
extending through tunnel portion 26. The air restriction discs also
are each provided with a slot 38a, 38b and 38c through which one of
the rods 19 or 20 is guided and the other rod received in securing
the discs. Notches 41a, 41b and 41c are also present in which one
of the rods is received in further stabilizing secured discs.
In securing a disc, it is simply placed on the device so that a
disc will fill or stopper one of the ports. A disc is secured by
passing rod 19 through a slot (38a) and pressing the disc in place
until rod 20 is received in slot 38a and rod 19 is received in
notch 41a.
Observing also FIGS. 6, 7 and 8, it will be noted that disc 32 not
only has a larger hollow center than discs 34 or 36 but that the
latter discs are respectively thinner. Thus, the thickness of each
disc corresponds to the width of the ports in which the respective
disc fits and preferably all are different so that each disc will
fit only one port. For this purpose not only may the port sizes
(distance between adjacent ribs) be different, but the width of
rods 19 and 20 between adjacent ribs as well as corresponding disc
slot and notch sizes may vary. Such a feature will prevent an
inexperienced operator from inadvertently placing the wrong disc on
the wrong port. This feature is further noted in observing FIG. 3
in which rod portions 44, 46 and 48 between adjacent ribs are
progressively smaller in both length and width. Correspondingly,
observing FIG. 5, the distance across slots 38a, 38b and 38c and
notches 41a, 41b and 41c are progressively smaller.
It should be appreciated that the device may have a different shape
as may the closure members. For example, rather than the ribs and
rods forming a generally frustoconical outline, ribs may be formed
with similar modification of the closure member shape in
rectangular, square, or other forms. Moreover, the discs may be
color coded to further distinguish them. Such modifications will be
evident to those skilled in the art without departing from the
purview of the invention.
In operation, the device is utilized and functions as follows:
Observing FIG. 10, oxygen supply tubing 44 is secured to nozzle
portion 12 and gas delivery portion 22 is inserted and received in
the end of oxygen delivery tube 46. The delivery tubing is
connected to oxygen mask 45 which is secured to a patient as shown.
Alternatively, the device may be secured directly to an oxygen mask
thereby eliminating delivery tubing if desired. The operator or
therapist then selects the desired oxygen concentration to be
delivered to the patient, for example, 24 percent, 28 percent, 35
percent or 40 percent. Where 24 percent oxygen is to be delivered
to the patient, none of the discs are inserted on the device so
that all three of gas entraining ports 13, 15 and 17 are open as
shown in FIGS. 1, 2 and 5. Accordingly, at an oxygen flow rate of
for example, 4 liters per minute the air entrained through the
ports provide an oxygen-atmospheric air mixture of about 24 percent
oxygen concentration delivered to the patient. For a 28 percent
oxygen concentration, disc 32 is inserted as shown in FIG. 6
closing appropriate oxygen entraining port. At the same flow of 4
liters per minute through the oxygen supply tubing an oxygen
concentration of 28 percent delivered to the patient will be
achieved. For 35 percent oxygen concentration, two of the
restriction discs are secured as shown in FIG. 7 and in order to
increase total flow to the patient, oxygen flow is increased, for
example, to eight liters per minute. With a third disc inserted to
close all of the air entraining ports as shown in FIG. 8, 40
percent oxygen concentration will be delivered to a patient.
Observing also FIG. 9, it will be noted that disc 36 has an oblong
hollow center so that there is a vent opening 35 adjacent nozzle
portion 12. Thus, even all closure members secured some air will be
entrained through the vent in order to avoid delivery of unduly
high oxygen concentrations. The size of such a vent opening of
course, may be varied to achieve any maximum oxygen concentration
desired.
Again, the shape of the ribs of the device of the invention is not
particularly critical and rather than being arcuate, they may be
rectangular, square or some other shape, so long as the air
entraining tunnel portion is not adversely affected. Further, the
port sizes and shapes may be varied as well as the number of ports
incorporated in such a device to achieve a series of different
oxygen concentrations as will be appreciated by those skilled in
the art. Although the closure members are shown as slotted and
notched so that they may be easily fitted over and secured on the
rods which extend between the forward-most rib and the forward end
of gas delivery portion 22, other design characteristics which
achieve the same purpose are intended to be within the purview of
the invention.
It will be appreciated that the device of the invention provides
varying oxygen concentrations on a single unit without the
requirement of having different devices for each different oxygen
concentration desired as have the corresponding prior art devices.
Accordingly, a single device of the invention can be used on a
single patient whereby varying oxygen concentrations may be
selected by simply inserting or removing one or more of the closure
members when the unit is to be used as previusly described. These
as well as other advantages will be evident to those skilled in the
art.
* * * * *