FIELD OF THE INVENTION
[0001] This invention pertains to lifesaving floatation devices inflated with respirable
gas and having mouthpieces to breathe the gas therein. More particularly, it pertains
to a floatation device having two inflatable compartments interconnected together
through a valve arrangement that is sequentially positioned to inhale from one compartment
and exhale into the other, and to re-breathe the previously-exhaled gas from the other
compartment in order to extend the breathing period thereof.
BACKGROUND OF THE INVENTION
[0002] A lack of breathing air and a need for floatation are often combined in a same catastrophic
event. For example, people trapped inside a submerged vehicle need breathing air to
get out of the vehicle and added buoyancy to swim to the shore. Similarly, smoke inhalation
and drowning are often combined risks in an air plane crash or in the case of a burning
ship. Home owners living near flood plains could also be exposed to smoke inhalation
from a house fire due to electrical short circuits caused by rising water, and drowning
when evacuating their house during an inundation. Therefore it is believed that a
need exists for a lifesaving device offering both floatation and oxygen supply for
at least a short period of time.
[0003] Conventional lifesaving devices for use in homes, vehicles, cottages and small crafts
are generally limited to containers of breathable gas, gas filters, floatation vests
and inflatable rafts. Both a breathing aid and floatation equipment are purchased,
stored and maintained separately and therefore, people often neglect to obtain one
or the other or both.
[0004] Examples of emergency oxygen or air supply devices of the prior art are described
in the following documents. These documents are divided in two groups. The documents
in the first group pertain to devices used to filter ambient air delivered to a mouthpiece,
and the documents in the second group pertain to devices incorporating a limited supply
of breathable gas contained under pressure in a small cylinder. Examples of the devices
of the prior art having a filter incorporated therein are as follows:
US Patent 4,515,156 issued to N. M. Khudosovtsev et al. on May 7, 1985;
US Patent 6,032,668 issued to C. Y. Chung on March 7, 2000;
CA Patent 2,084,765 issued to L. J. Swann on November 12, 1996.
[0005] Examples of breathing devices having a supply of respirable gas included therein
are as follows:
US Patent 2,831,607 issued to A. J. Berndt on April 22, 1958;
US Patent 4,440,163 issued to G. Spergel on April 3, 1984;
US Patent 5,979,442 issued to R. J. Orr on November 9, 1999;
US Patent 6,412,482 issued to C. D. Rowe on July 2, 2002;
[0006] Both the filter and the pressurized cylinder types of breathing devices are advantageous
to prevent inhalation of smoke or toxic gases for example for a period of time which
is sufficiently long to allow a person to get away from a danger area. In the case
of the
CA Patent 2084,765 for example, a supply of breathable air for a period of 10 minutes is suggested.
In another example, the
US Patent 4,440,163 suggests a supply of respirable air for a period of about 5 minutes.
[0007] In regard to prior art in the field of inflatable lifesaving devices, the following
documents represent good examples of floatation equipment that are inflatable by mouth
of the user:
US Patent 2,742,654 issued to V. H. Hurt on April 24, 1956;
US Patent 5,516,233 issued to W. L. Courtney on May 14, 1996;
US Patent 4,813,899 issued to H. Fujimoto on March 21, 1989.
[0008] Although the above inflatable devices have a mouthpiece connected to one or more
inflatable bags, each mouthpiece is equipped with a check valve that prevents re-breathing
from the bags. These devices are therefore not appropriate for preserving someone's
life in a hazardous situation requiring both floatation and respirable air.
[0009] More relevant prior art devices preceding the present invention consist of floatation
vests, each being made of two compartments from which at least one contains respirable
air and is equipped with a hose and a mouthpiece for inhaling the air from the bag.
These floatation vests are described in the following documents:
US Patent 3,866,253 issued to A. J. Sinks et al. on February 18, 1975;
US Patent 3,877,425 issued to W. J. O'Neill on April 15,1975;
US Patent 4,324,234 issued to S. G. Maness on April 13, 1982.
[0010] In the case of
US Patent 3,866,253, a diver wearing the vest can inflate one of the compartments by mouth, and where
necessary, re-breathe the air from this compartment. The other compartment is inflated
by a cartridge of compressed CO
2gas. The
US Patent 4,324,234 suggests a dual-chamber vest wherein one of the chambers is filled with compressed
air or breathable gas and the other is filled with CO
2 gas. The document suggests an amount of air sufficient to re-breathe from the bag
for a period of 3 to 5 minutes to escape from a danger situation.
[0011] One of the problems associated with a pressurized gas container used in a breathing
device is that the discharge of the container into the bag of the device increases
the pressure of the breathable gas inside the bag or vest and makes in difficult,
at least initially, to control the flow of gas through a mouthpiece. The pressure
surge of the discharging cylinder is susceptible of causing a wearer to inadvertently
over-breathe or otherwise let escape a substantial amount of gas through the mouthpiece,
and to waste a portion of the lifesaving feature of the device. Therefore conventional
breathing apparatus using pressurized cylinders have pressure regulators incorporated
therein or calibrated orifices to limit the flow of gas to the mouthpiece.
[0012] However, a pressure regulator mounted in a lifesaving breathing device increases
the manufacturing cost of the device and is believed to be a determining factor limiting
the accessibility of the device to a large number of people. Similarly, the use of
an orifice in a breathing device limits the amount of air available to the user at
any given time. As the pressure drops in the supply cylinder, the flow of gas also
drops across the orifice and to the mouthpiece. This reduction of flow to the mouthpiece
could induce a sense of panic to the user.
[0013] On the other hand, when the respirable gas is expanded in a bag at atmospheric pressure,
it is estimated that a volume of gas of about 660 cubic inches is required for each
minute of breathing time. A bag containing 3 to 5 minutes worth of breathable gas
can be seen as a serious encumbrance to get out of a cramped space in a danger situation.
[0014] As such, it may be appreciated that there continues to be a need for a new and improved
lifesaving floatation and breathing device having a reasonable volume of breathable
air therein and which operates without a pressure regulator or an orifice.
SUMMARY OF THE INVENTION
[0015] The floatation and breathing device according to the present invention is inflated
from a pressurized cylinder containing breathable gas. The breathable gas is discharged
into a bag having an appropriate volume to accept the full content of the cylinder
at atmospheric pressure, thereby obviating the need for a pressure regulator or flow
control orifice.
[0016] In a broad aspect of the present invention, there is provided a lifesaving floatation
and breathing device comprising first and second inflatable bags having similar bag
volumes, and a mouthpiece communicating with both bags. A pressurized gas cylinder,
or other container, filled with breathable gas is mounted to one of the bags. This
pressurized cylinder has a nominal gas volume and a nominal gas pressure therein The
device also has an inflator mechanism for transferring the breathable gas from the
pressurized gas cylinder into one of the bags. In this device, the volume of each
bag corresponds to a mathematical product of the nominal gas volume inside the cylinder
and a ratio of the nominal gas pressure inside the cylinder over atmospheric pressure.
[0017] Therefore when the gas from the pressurized cylinder is transferred into the bag,
this gas is easily breathable at atmospheric pressure. Also, the exhaled gas which
still contains a substantial amount of oxygen is stored in the second bag for eventually
re-breathing it. The buoyancy of the device is thereby maintained and the breathing
period of the original breathable gas cylinder is substantially increased.
[0018] In another aspect of the present invention, there is provided a selector valve in
communication with the mouthpiece, and hoses or conduits between the selector valve
and each of the bags. The selector valve has a pair of check valves mounted therein
communicating with the hoses or conduits and the mouthpiece to control a gas flow
in the mouthpiece to and from the bags. The check valves are mounted inside a circular
dial, in opposite air-flow orientations relative to each other. The dial is movable
relative to the base of the selector valve from a first position to a second position.
In the first position, the check valves allow inhaling oxygen gas from the first bag
and exhaling into the second bag. In the second position, the check valves allow the
re-breathing of the previously exhaled gas, and exhaling in the first bag. Although
the oxygen content in the first exhaled gas is somewhat reduced, it is believed to
be appropriate for re-breathing again in a life threatening situation.
[0019] It will be appreciated that when the first-inhaled gas is rich in oxygen, the position
of the selector valve can be inverted several times, to allow re-breathing gas from
the inflated bag and to exhale and inflate the other bag, until the exhaled gas reaches
a minimum breathable oxygen content.
[0020] In another aspect of the present invention, each bag has the shape of a horseshoe
having a first end and a second end. The pressurized cylinder has means to introduce
the breathable gas in the first end of the first bag and the selector valve is in
communication with the other end of that same bag. Because of these opposite mountings,
a pressure surge inside the bag when the gas from the cylinder is introduced into
the bag all at once has negligible effect on the gas pressure at the mouthpiece.
[0021] In yet another aspect of the present invention, there is provided a floatation and
breathing device comprising a front bag and a rear bag each having an upper end and
a lower end, and a mouthpiece mounted to the upper ends. The bags share a common membrane
and jointly define the shape of a pillow. In this embodiment, the pressurized cylinder
has means to introduce the breathable gas in the lower end of the front bag. Again,
the pressure surge from discharging the pressurized cylinder inside one of the bags
has little effect on the gas pressure at the mouthpiece. Furthermore, the pressure
surge caused by the discharging of the gas cylinder into one of the bags when the
bags are in a folded form, helps to expand the bags from their folded form.
[0022] This brief summary has been provided so that the nature of the invention may be understood
quickly. A more complete understanding of the invention can be obtained by reference
to the following detailed description of the preferred embodiments thereof in connection
with the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Two embodiments of the present invention are illustrated in the accompanying drawings,
in which like numerals denote like parts throughout the several views, and in which:
FIG. 1 is a perspective front and side view of the floatation and breathing device according
to the first preferred embodiment of the present invention, worn by a user;
FIG. 2 is a front view of the first preferred floatation and breathing device;
FIG. 3 is a side view of the first preferred floatation and breathing device, showing the
front bag in a deflated mode and the rear bag in an inflated mode;
FIG. 4 is a front view of the rear bag of the first preferred floatation and breathing device
as seen when separated from the front bag;
FIG. 5 is a front view of the mouthpiece, the extensible hose and selector valve mountable
to the first preferred embodiment of the preferred invention;
FIG. 6 is a front view of the selector valve shown in FIG. 5 without the extensible hose and mouthpiece;
FIG. 7 is a side view of the selector valve shown in FIG. 6;
FIG. 8 is an enlarged diametrical cross-section of the selector valve illustrated in FIGS. 5-7, as seen along line 8-8 in FIG. 6;
FIG. 9 is an enlarged diametrical cross-section view of a check valve used in the selector
valve of the first and second preferred embodiments of the present invention;
FIG. 10 is a front view of the floatation and breathing device according to the second preferred
embodiment of the present invention;
FIG. 11 is a cross-section view of the selector valve used in the second preferred embodiment;
FIG. 12 illustrates the floatation and breathing device according to the second preferred
embodiment in a folded mode.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0024] While this invention is susceptible of embodiment in many different forms, there
are shown in the drawings and will be described in details herein two specific embodiments,
with the understanding that the present disclosure is to be considered as an example
of the principles of the invention and is not intended to limit the invention to the
embodiments illustrated and described.
[0025] The floatation and breathing device according to the first preferred embodiment is
illustrated in
FIGS. 1 to
9. This first preferred floatation and breathing device
20 has the form of a life vest and can be worn by a user. This first preferred embodiment
is also referred to herein as the life vest
20.
[0026] The life vest
20 is made of a front bag
22 and a rear bag
24. The front bag
22 is separate from the rear bag
24. The front bag
22 is inflatable with exhaled air by the user, by mean a mouthpiece
26 and a flexible and extensible tube
28. The rear bag
24 is inflatable with oxygen by means of a high pressure gas cylinder
30 and a manual inflator
32. Each bag has the shape of a horseshoe with a central hole and two lower ends on
opposite sides thereof. The gas cylinder
30 preferably contains a breathable gas mixture having a high oxygen content, such as
90% oxygen for example.
[0027] Referring particularly to
FIGS. 1 to 4, the front bag
22 and the rear bag
24 are retained to each other by central tendons
32 extending around the central hole or the neck of the life vest, and by a pair of
side tendons
34 extending from the sides of the life vest. A belt
36 is also provided and is fastened to the lower front end of the life vest
20. In use, the life vest
20 is worn as a bib and is attached to the waist of the user as illustrated in
FIG. 1.
[0028] The life vest
20 also comprises a selector valve
40 communicating with both bags
22, 24 by way of two hoses. The hose mounted to the front bag
22 is referred to as the exhaled air hose and is labelled
42. The hose mounted to the rear bag
24 is referred to as the oxygen hose and is labelled
44. The oxygen hose
44 is mounted at one end of the horseshoe shape on the rear bag
24, and the pressurized gas cylinder
30 and the manual inflator
32 are mounted at the opposite end of that same bag.
[0029] Each of the hoses
42, 44 is mounted to a respective bag using a manifold stem valve
46 such as a stem valve, part no. 830 AOE manufactured by Halkey-Roberts™, in which
the valve spring and mechanism have been removed, and a corresponding eye-ring fitting
48 at the end of each hose, enclosing the stem valve
46. The manual inflator
32 is also mounted to a manifold valve
46 as specified above without modification. The manual inflator
32 is also available from a selection of different inflators manufactured by Halkey-Roberts™,
or other manufacturers. The preferred inflator
32 is operable by pulling on a handle
50 which is tied to the inflator's mechanism by a string
52. The preferred inflator
32 is labelled as part 840 AM. Halkey-Roberts™ is located in St-Petersburg, Florida,
USA.
[0030] The high-pressure cylinder
30 has a preferred volume of about 4.85 cubic inches and contains oxygen-rich breathable
gas at a pressure of about 2000 psi. Both bags
22, 24 have a respective volume of about 660 cubic inches.
[0031] When the breathable gas from the cylinder is released in the rear bag
24, this bag is inflated to a pressure that is substantially the same as the atmospheric
pressure. Therefore, there is no need for a pressure regulator or a flow control orifice
to control the flow of gas to the mouthpiece
26. This breathable gas is readily available for breathing, through the oxygen hose
44 and the selector valve
40. A volume of 660 cubic inches is believed sufficient to provide breathable gas to
a person for a period of about one minute.
[0032] Because the oxygen hose
44 is connected to the rear bag
24 on the opposite side of the manual inflator
32, the pressure surge created by the sudden release of breathable gas from the high
pressure cylinder
30 is partly absorbed in the inflation of the rear bag
24, and therefore does not cause a significant increase in pressure in the oxygen hose
44 and in the selector valve
40.
[0033] In use, the life vest
20 may be put on by a user, and the handle
50 is pulled down quickly and firmly to puncture a diaphragm (not shown) in the neck
of the high pressure cylinder
30. The breathable gas is released into the rear bag
24 thereby inflating the rear bag
24. Using the mouthpiece
26 with the selector valve
40 in an initial position, the user inhales breathable gas from the rear bag
24 and exhales a mixture of oxygen and CO
2 into the front bag
22. The buoyancy of the life vest
20 is thereby maintained.
[0034] Both bags
22, 24 are made of a flexible, weather-resistant and gas-tight material. A pair of handles
52 are provided on the front bag
22 to allow a user to hold on to the life vest
20 by hand as if it was a pillow for example. The handles
52 are also advantageous to assist a user in squeezing the air out of one of the bags.
[0035] It is known that ambient air contains about 21% oxygen. It is also known that a recommended
minimum oxygen content in breathable air is about 15%, because a lower amount could
cause hallucinations. It is further known that a person breathing normally consumes
about 5% of the oxygen present in ambient air, while a person hyperventilating in
a panic situation absorbs only about 3%. Therefore, it is believed that in many circumstances,
the air exhaled into the front bag
22 of the life vest
20 still contains oxygen and can be re-breathed again.
[0036] When the breathable gas in the high pressure cylinder
30 is a mixture of gas rich in oxygen, such as 90% oxygen for example, this gas can
be re-breathed several times before it reaches the 15% lower limit. Therefore, the
selector valve
40 in the life vest
20 according to the first preferred embodiment is rotated nan a turn to allow the re-breathing
the once-exhaled air and to allow exhaling in the rear bag
24. The selector valve
40 can be rotated once more to re-breathe the twice-exhaled gas from one bag and exhaled
in the other. In other words, the selector valve
40 is rotated as required to breathe from the inflated bag and to exhale and inflate
the other bag.
[0037] Referring now to
FIGS. 5 to
9, the operation of the selector valve
40 will be explained in details. The selector valve
40 constitutes a base from which extends the flexible tube
28 leading to the mouthpiece
26. The selector valve
40 has a cylindrical shape, a base portion
60 and a circular dial
62 to which is mounted the flexible tube
28 and the mouthpiece
26. The base portion
60 has flat tabs
64 extending therefrom. These tabs
64 are sewn, glued or bonded to the life vest
20 to retain the selector valve
40 to the life vest
20. A pair of hose nipples
66 extend radially from the base portion
60. The exhaled air hose
42 and the oxygen hose
44 are mounted to these hose nipples
66.
[0038] Referring particularly to
FIGS. 8 and
9, the base portion
60 of the selector valve
40 has a pair of conduits
70, 72 therein extending parallel to the axis of the valve
40. Each conduit
70, 72 communicates with one of the hose nipples
66. These conduits
70, 72 are open at their top ends and closed at their bottom ends by a pair of pipe plugs
74.
[0039] The dial
62 is mounted atop the base portion
60 and is held to the base portion
60 by a snap ring
76 and a stem
78 extending upward from the centre of the base portion
60. The snap ring
76 is engaged into a groove on the end of the stem
78. A spring disc
80 is also provided under the snap ring
76 to retain the dial
62 to the base portion
60 with a light pressure.
[0040] The dial
62 has a pair of cavities
84, 86 therein in which are respectively mounted an inhale check valve
88 and an exhale check valve
90. Each of the cavities
84, 86 communicates with a respective conduit
92 or
94 extending into the lower end of the flexible tube
28, and joining the flexible tube
28 to both check valves
88, 90. The dial
62 has a shoulder
96 on its
bottom surface and an O-ring
98 circling that shoulder. The shoulder
96 and the O-ring
98 have dimensions to mount into a circular groove
100 in the upper surface of the base portion
60 so to seal the dial
62 to the base portion
60.
[0041] Each of the check valves
88, 90 has a valve seat
110 which is force-fitted into a respective cavity
84 or
86. A valve stem
112 extends from the valve seat. A valve disc
114 is mounted to the valve stem
112 and is urged against the valve seat
110 by a compression spring
116 fastened to the valve stem
112. The compression spring
116 is calibrated so that the valve disc
114 opens under a pressure of about between 1-5 psi. The locations of the breathable
gas cylinder
30 and of the oxygen hose
44 on opposite sides of the oxygen bag
24, and the size of the oxygen bag make it unnecessary to use stronger check valves.
Consequently, the content of the life vest
20 is breathable without effort.
[0042] In use, the content of the oxygen bag
24 is inhaled first. The dial
62 is rotated half a turn to interchange to positions of the check valves
88 and
90. Then, the content of the front bag
22 can be re-breathed, while exhaling into the oxygen bag
24. In extreme situations, as explained before, the dial
62 can be rotated back to its initial position to re-breathe the exhaled gas a second
time, and still find in it a quantity of oxygen gas.
[0043] Referring now to
FIGS. 10-12, the floatation and breathing device according to the second preferred embodiment
will be described. The second preferred floatation and breathing device
120 has the shape of a pillow, and is referred to herein as the pillow
120. This pillow also has a front compartment
122 and a rear compartment
124 separated from each other by a gas-tight membrane
126. Each of the compartments, also referred to herein as bags for corresponding to the
bags in the first preferred embodiment, has a volume sufficiently large to receive
660 cubic inches of gas at atmospheric pressure. Both compartments or bags
122, 124 are made of a flexible, weather-resistant and gas-tight material.
[0044] A mouthpiece
26 and a flexible tube
28 are mounted to a selector valve
126 which is bonded to the upper end of the pillow
120. A high pressure breathable gas cylinder
30, a manual inflator
32, and a manifold valve
46 as previously described, are mounted to the bottom end of the pillow
120. The breathable gas cylinder
30 in this embodiment also contains about 4.85 cubic inches of oxygen-rich breathable
gas at a pressure of about 2000 psi. A pair of handles
52 are provided to allow a user to retain the pillow against himself/herself by hand.
[0045] The selector valve
126 is similar in structure to the previously described selector valve
40 except that the base portion
128 thereof has two segments
130, 132 extending astride the top end of the pillow, with a conduit
134, 136 extending in each segment joining respectively the valve cavities
84, 86 to the compartments
122, 124. The base portion
128 of the valve is made of a material which can be vulcanized or otherwise bonded to
the material of the pillow
120.
[0046] The pillow
120 is foldable in half and then in three segments as suggested by the fold lines
140 illustrated in
FIG.10 to obtain a compact arrangement as illustrated in
FIG. 12. In the folded mode, the pillow
120 is easily packaged in a pouch (not shown) for example and stowed away. In the folded
mode, the mouthpiece
26 and the handle
50 of the manual inflator
32 are clearly visible at one end of the package, and therefore, its use and purpose
are self-explanatory.
[0047] Because of the location of the manual inflator
32 on the bottom end of the front face of the pillow
120, the operation of the manual inflator
32 causes the pillow
120 to unfold and to expand on its own from a folded form. An inscription on the dial
62 reads " ½ TURN TO REBREATHE". This inscription is clearly visible when the pillow
120 is pulled out of its storing pouch, such that a user can understand at a glance the
procedure to re-breathe the air from the exhaled air compartment
124 when the oxygen compartment becomes empty.
[0048] As to other manner of usage and operation of the present invention, the same should
be apparent from the above description and accompanying drawings, and accordingly
further discussion relative to the manner of usage and operation of the invention
would be considered repetitious and is not provided.
[0049] While two embodiments of the present invention have been illustrated and described
herein above, it will be appreciated by those skilled in the art that various modifications,
alternate constructions and equivalents may be employed without departing from the
true spirit and scope of the invention. For example, the check valve described and
illustrated herein is only one type of check valves available for mounting in the
lifesaving devices according to the present invention. Also, it will be understood
that although the operation of the lifesaving devices as described herein consists
of breathing from one bag and exhaling in the other, the selector valve can be used
to inflate both bags, to increase the buoyancy of the device in circumstances where
floatation is more important than oxygen supply. Therefore, the above description
and the illustrations should not be construed as limiting the scope of the invention
which is defined by the appended claims.
1. A lifesaving floatation and breathing device comprising;
first and second inflatable bags attached to each other and each having a bag volume;
a mouthpiece having conduit means communicating with said bags;
a pressurized gas container filled with breathable gas affixed to said first bag,
said pressurized gas container having a gas volume and a gas pressure therein, and
means mounted to said pressurized gas container for transferring said breathable gas
from said pressurized gas container into said first bag;
wherein said bag volume in each of said inflatable bags is a mathematical product
of said gas volume inside said pressurized gas container and a ratio of said gas pressure
inside said pressurized gas container over atmospheric pressure.
2. The lifesaving floatation and breathing device as claimed in claim 1, wherein said conduit means comprises a selector valve.
3. The lifesaving floatation and breathing device as claimed in claim 2, wherein said conduit means also comprises a first conduit communicating with said
first bag and a second conduit communicating with said second bag, and first and second
check valves respectively mounted in said first and second conduits; said check valves
being mounted in opposite air-flow orientations relative to each other for controlling
a gas flow in said mouthpiece to and from said bags.
4. The lifesaving floatation and breathing device as claimed in claim 3, wherein each of said check valves has an opening pressure setting of between about
1 psi and 5 psi.
5. The lifesaving floatation and breathing device as claimed in claim 3, wherein said selector valve has means to invert a position of said check valves relative
to said first and second conduits to allow a re-breathing of previously exhaled gas
in one of said bags.
6. The lifesaving floatation and breathing device as claimed in claim 5, wherein said means to invert a position of said check valves comprises a rotatable
circular dial.
7. The lifesaving floatation and breathing device as claimed in claim 6 further comprising a flexible and extensible hose mounted between said mouthpiece
and said dial.
8. The lifesaving floatation and breathing device as claimed in claim 7, further comprising means to retain said selector valve to at least one of said bags.
9. The lifesaving floatation and breathing device as claimed in claim 1, further comprising a handle attached to a surface of one of said bags.
10. A lifesaving floatation and breathing device comprising,
first and second inflatable bags attached to each other and each having a bag volume
and a shape of a life vest;
a mouthpiece mounted to one of said bags and comprising conduit means communicating
with both said bags;
a pressurized gas container filled with breathable gas affixed to one of said bags,
and having a gas volume and a gas pressure therein, and
means mounted to said pressurized gas container for transferring said breathable gas
from said pressurized gas container into said first bag;
wherein said bag volume in each of said bags is a mathematical product of said gas
volume inside said pressurized gas container and a ratio of said gas pressure inside
said pressurized gas container over atmospheric pressure.
11. The lifesaving floatation and breathing device as claimed in claim 10 wherein said bags comprise a front bag and a rear bag relative to each other, each
having a horseshoe shape and first and second lower ends on opposite sides thereof.
12. The lifesaving floatation and breathing device as claimed in claim 11 wherein said pressurized gas container has means to introduce said breathable gas
in said first end of said horseshoe shape in said rear bag.
13. The lifesaving floatation and breathing device as claimed in claim 12, wherein said conduit means comprises a selector valve, and first and second hoses
respectively mounted between said selector valve and each of said front and rear bags,
and said hose between said selector valve and said rear bag being affixed to said
second end of said horseshoe shape.
14. The lifesaving floatation and breathing devices as claimed in claim 13, wherein said conduit means also comprises a first conduit communicating with said
first hose and a second conduit communicating with said second hose, and first and
second check valves respectively mounted in said first and second conduits; said check
valves being mounted in opposite air-flow orientations relative to each other for
controlling a gas flow in said mouthpiece to and from said bags, and said selector
valve has means to invert a position of said check valves relative to said first and
second conduits to allow re-breathing of previously exhaled gas.
15. A lifesaving floatation and breathing device comprising,
first and second inflatable bags each having a bag volume; said first and second inflatable
bags being superimposed over each other and jointly defining a shape of a pillow;
a mouthpiece affixed to said first and second bags and comprising conduit means communicating
with said bags;
a pressurized gas container filled with breathable gas affixed to one of said bags,
and having a gas volume and a gas pressure therein, and
means attached to said pressurized gas container for transferring said breathable
gas from said pressurized gas container into one of said bags,
wherein said bag volume is a mathematical product of said gas volume inside said pressurized
container and a ratio of said gas pressure inside said pressurized container over
atmospheric pressure.
16. The lifesaving floatation and breathing device as claimed in claim 15 where said inflatable bags comprise a front bag and a rear bag each having an upper
end and a lower end, and said mouthpiece being bonded to said upper ends.
17. The lifesaving floatation and breathing device as claimed in claim 16 wherein said pressurized gas container has means to introduce said breathable gas
in said lower end of said front bag.
18. The lifesaving floatation and breathing device as claimed in claim 12, wherein said conduit means further comprises a selector valve.
19. The lifesaving floatation and breathing devices as claimed in claim 18, wherein said conduit means also comprises a first conduit communicating with said
first bag and a second conduit communicating with said second bag, and first and second
check valves respectively mounted in said first and second conduits; said check valves
being mounted in opposite air-flow orientations relative to each other for controlling
a gas flow in said mouthpiece to and from said bags, and said selector valve has means
to invert a position of said check valves relative to said first and second conduits
to allow re-breathing of previously exhaled gas.
20. The lifesaving floatation and breathing device as claimed in claim 15, wherein said first and second inflatable bags have a common membrane therein.