Note: Descriptions are shown in the official language in which they were submitted.
CA 02634651 2008-07-08
BREATHING APPARATUS AND PRESSURE
VESSELS THEREFOR
FIELD OF THE INVENTION
The present invention relates to self-contained breathing apparatus, and mqre
particularly to breathing apparatus in the nature of a vest worn by a user
having
pressurized cylinders orflasks of breathable airdistributed in thevest, self-
contained
underwater breathing apparatus and specifically, self-contained breathing
apparatus
that may be wom by the user. The apparatus is used for, among other things,
firefighting, emergency air supply for workers in hazardous environments or
underwater use.
BACKGROUND OF THE INVENTION
The disadvantages of previous air breathing apparatus include their weight,
bulk,
awkwardness, restrictions they create in closed confinement spaces, their risk
of
explosion and the marginal minutes of breathable air they provide in both
emergency
and continuous duty situations.
Previous designs have often put the air supply either high on the back of the
user or
to the side of the user, causing the user'S centre of grsvity to be shifted,
thus creating
strain on the user when wearing the apparatus and making continuous use of the
apparatus difficult.
Further, in in'dustry, emergency escape apparatus typically only provide 5
minutes to
15 mfnutes of breathable air. This gives the user a false sense of security
since
documented evidence shows that in many cases more tirne is required. For
miners,
accidents can require that the miner have one to two hours of breathable air
to allow
for safe evacuation. Construction workers building additions beside operating
gas
plants and refineries have found Insufficient evacuation routes in the past
and found
a 5-16 minute emergency air supply was not enough.
-1-
CA 02634651 2008-07-08
Other problems with self-contained breathing apparatus include the fact that
they do
not compensate for the size of the user, It is a well known fact that a large
person
consumers more air per minute than a srnaller person. Thus by providing the
same
emergency device to both individuals, tho large person will have less time to
safely
escape the hazardous situation.
One of the main drawbacks to increasing eir supply is the weight of tanks to
carry the
air. These tanks are generally large metal cylinders that are charged to
approximately 3000 psi.
Orie solution to the weight problem is to create composite vessels with a
metal liner
and a composite structural component. These vessels still however have to be
sufficiently strong to prevent failure, and thus the pressure in these vessels
is limited.
Another problem with current air vessels, especially filament-epoxy wound
containers, is that they have several deficiencies. These vessels do not have
a good
Impact resiatence capability, and are susceptible to rupturing If damaged.
Further,
rupturing of these vessels generally causes fragments to be propelled at high
speeds,
endangering those near the vessel.
Another problem with fibre-epoxy windings is that they do not withstand
adverse
environmental conditions very well. Exposure to caustic environments Is
possible,
for exarnple, in firefsghting applicatiorls or in breathing devices designed
for
evacuation from chemical or industrial plants. These devices therefore need
protection from the adverse environment.
SUMMARY OF THE INVENTION
The present air vest apparatus addresses all of the above problems- for
existing self-
contained breathing apparatus. This vest device is. engineered to provide a
self-
contained breathing apparatus option suited for closed confinement
applications in
all of the categories for fire fighting, industrial, marine and aircraft
environments.
-2-
CA 02634651 2008-07-08
The compactness of the vest, the longer duration of its air supply due to the
variety
of the numberof possible cylinderorflask,combinations, its diminished
explosive risk
and the unique compartmentalization of the vests allows an Increased amoUnt of
breathable minutes of air In the garments. The air vest incorporates the
function of
being able to calibrate the breathable minutes of air on an individual basis.
The advantages of the air vest garment can create new categories of field
applications as an emergency escape apparatus and as a working ("prolonged
use"
or "continuous duty") apparatus. It is enVisioned that some of these new
categories
will include Emergency Preparedness for diplomat personnel, government
employees, highrise off'ice workers, polioe tactical units, armed forces,
naval ship
personnel, passenger and cargo ship personnel, aircraft personnel, hotel and
motel
employees, rail workers, drivers transporiing hazardous goods, asthmatics
requiring
a portable oxygen supply, residents living In the proximity of possible
hazardous
incidents, lab technicians, and construction workers, particularly those
working in or
near potential hazards.
The air vest technology provides a unique, versatile compact design with
considerable fiexibility as to the numerous cylinder or flask combinations.
Specific
Job task assignments will dictate: (1) the number of cylinders or flasks; (2)
whether
the cylinders or flasks are composite or metallic compounds; (3) the size of
the
cylinders or flasks; and (4) the working pressure of each particular model.
Inasmuch as a preferred objective is to engineer an air vest with minimal
thickness,
dimensional ne.iuctions of the cylinders orflasks will provide reduced vest
thickness.
With a view towards allowable working pressures above the "industry-norm",
there
is provided a high strength flexible pver-wrap for use on pressure vessels.
Specifically, one aspect of the present invenfion provides for the use of a
carbon
composite filament saturated with a liquid rubber compound which is wound
around
an existing pressure vessel and cured. In a preferred embodiment the carbon
composite is KevlarT".
M3-
CA 02634651 2008-07-08
The carbon fibre over-wrap of the preserft invention is used to add strength,
impact
resistance, explosion containment, and exposure protection to any existing
pressure
vessel.
By alleviating the explosive risk of high pressure cylinders with the
incorporatian of
the containment overwrap, It may become possible to initiate applications to
increase
the standard working pressures of SCBA (self contained breathing apparatus)
and
SCUBAs (self contained underwater breathing apparatus).
The containment overwrap should also allow the exterior surface of the
composite
cylinders or flasks to maintain a pristine quality for an extended number of
years
relative to prior art in the field.
In order to allow higher air pressure to be used in cylinders, there may
additionally
be provided a metal braid containment overwrap. The braided
containmentoverwrap
creates a net around the cylinder or flask and confines propelled fragments
from a
ruptured cylinder or flask.
To provide for a user's safety, there are also provideNd deflector plates
whlch are
secured between the cylinders or flasks andthe user. These plates are
comprised
of a new carbon fiber core material.
The high pressure cylinders or flasks are attached within pockets of the
present vest
garment, device. The flasks or cylinders are Interconnected with low pressure
pneumatic hose between each other and the second stage regulator at chest
height
which supplies air on demand to the respirator-face piece. This design
therefore is
relatively compact, lightweight and easy to use. A combination high-pressure
shut-off
valve, first stage regulator and low pressure valve are contained in the
regulator-valve
body attached to each cylinder or flask. This device regulates the cylinder or
flask's
working pressure down to 30 psi - 60 psi. The reduced pressure is supplied
into a
-4-
CA 02634651 2008-07-08
low pressure pneumatic hose which interconnects all of the cylinders or flasks
to the
second stage regulator at chest height on the front of the vest garment.
A further pneumatic hose connects the second-stage regulator and the face-
piece.
Air pressure is reduced to atmospheric pressure by the second-stage regulator.
in some applications, the pneumatic hose will be replaced with a metal air
manifold.
The present invention therefore grovides a wearable garment apparatus capable
of
supplying air to a user comprising a plurrality of compartments disposed about
said
garment; a piurality of air storage means for fitting into respective ones of
said
compartments; regulator means; conduit for connecting said plurality of air
storage
means to said regulator means; and a breathing member eonnected in fluid
communication to said regulator means; wherein said breathing means allows a
user
to receive air from'said plurality of air storage means.
The present Invention further provides a composite carbon fibre core
comprising a
first carbon fibre fabric layer; a second carbon fibre fabric layer; and an
inner layer
of carbon fibre disposed between said='Brst and second layers; wherein said
inner
layer of carbon fibre has carbon fibres disposed substantially perpendicularly
to
carbon fibres within said first and secortd carbon fibre fabric iayers.
The present invention still further provides a method for making a composite
carbon
fibre core comprising the steps of placing a first carbon fibre fabric layer
substantiaiiy
horizontally; creating a se.cond layer through the steps of placing mixed
carbon fibre
and epoxy materials Into a mould; and cutting layers from said mixed
materials;
placing said second layer over said frr$t layer; placing a third layer of
carbon fibre
fabric over said second layer; and curing the combination.
The present invention yet further provides an air containment vessel
comprising an
inner bladder made of rubber; a structural core; an outer rubber cover; and an
air
outlet; whereby said inner bladder fits concentrically within said core and
said core
_5-
CA 02634651 2008-07-08
fits concentrically within said outer cover, and whereby said air outiet
provides fluid
communication for air leaving and enterinp said vessel.
The present invention still further provides a method of making a composite
carbon
fibre air containment vessel having an intemal bladder, comprising the steps
of
creating a wax module in the shape of the inside of the air containment
vessel;
inserting an air inlet tube into one end of said wax module; dipping said wax
module
into a liquid to form a layer of bladder material on sald wax module; allowing
said
layer to cure; filament winding a carbon fibre core over said bladder layer;
curing the
carbon fibre core by heating, thereby also melting the wax module; dipping
said
carbon fibre care into liquid rubber creating an outer rubber layer; and
allowing said
outer rubber layer to cure.
The present invention still further provides a containment means for a
pressurized
fluid vessel comprising a plurality of wires wrapped about said vessel; a
plurality of
fastening means for securfng the ends of respective ones of said wires
together, said
fastening means having energy absorbing means therein to allow controlled
expansion of soid wire in the event of vessel failure; and whereby each wire
can be
affixed at a second end to a lug using cones and stoppers within the lug.
The present invention yet further provides a protective over-wrap for a
pressure
vessel comprising a carbon composite thread; and a liquid rubber; wherein said
carbon composite thread is immersed in said liquid rubber and subsequently
wound
about said pressure vessel, and wherein said pressure vessel with said carbon
composite thread and liquid rubber winding are then cured.
The present invention further provides a method of creating a proteCtive over-
wrap
for pressure v ssels comprising the steps of saturating a carbon-composite
thread
In a liquld rubber compound; winding said saturated thread about said pressure
vessel; and curing said pressure vessel and saturated thread; whereby said
rubber
and carbon composite thread comprise said protective over-wrap.
~6-
CA 02634651 2008-07-08
BRIEF DESCREpTION OF THE DRAWINGS
Preferred embodiments of the present invention will now be described in
greater
detail and will be better understood when read in conjunction with the
following
drawings in which:
Figure 1 is a schematical view of the vest apparatus as seen from the rear;
Figure 2 is a schematical view of the vest apparatus as seen from the front;
Figure 3 is a cross sectional view of a preferred embodiment'of a high
pressure
vessel and fitting;
Figure 4 is a cross sectional view of a second plate and nut arrangement that
may
be attached to the fittings of Figure 2;
Figure 5 is a cross sectional view of a high pres$ure vessel,
Figure 6 is an enlarged cross sectional vi'ew of a portion of the vessel of
Figure 3;
Figure 7 is an end view of a wax module for creating the vessel of Figure 3;
Figure 8 is a side view of a wax module fpr creating the vessel of Figure 3;
Figure 9 is a perspective view of a modified shape of an air vessel including
aT"
ftting;
Figure 10 is a perspective view of another embodiment of a pressure vessei,
including a regulator;
Figure 11 is a schematical view of a containment bag for the vessel of Figure
3;
Figure 12 is a cross sectional view of a suppression device used in the
containment
bag of Figure 11;
-7-
CA 02634651 2008-07-08
Figure 13 is the prior art configuration of an "i-beam" balsa wood core
composite;
Figure 14 is a cross section showing a new pure carbon fibre composite
material;
Figure 15 is a view of a prior art regulator-valve body assembly; and
Figure 16 is a cross sectional view of a vessel with a protective ovenarrap.
DETAILED DESCRIPTION OF THE DRAWINGS
The present invention consists of a compact, lightweight, self contained air
breathing
apparatus in the form of muitiple, high pressure vessels or vessels that are
contairned
within a body vest and in a preferred embodiment are designed to provide a
user with
at least 30 minutes of breathable air.
Referring to Figures 'i and 2, the construction of the vest apparatus I in the
present
invention consists of a series of distinct components that are interconnected
in order
to provide the functionality of the apparatus. These components include a
series of
high pressure vessels 10 or vessels that are Interconnected, a containment bag
50
(Figure 11) or device to protect a user in the case of a rupture of one of the
high
pressure vessels, an explosion shield 65 placed within the vest and between a
user
and the high pressure vessels in order to further protect a user in the case
of an
explosion or rupture of one of the vessels, a breathing piece 49, and the vest
structure I comprised of a material suited to the envisioned use of that
particular vest
apparatus. Further features such as pressure monitoring sensors and alarms,
straps
7 for securing the vest apparatus more securely to a user, regulators, T
fittings, etc.,
may also be included in the vest. Each of these components and how they
interconnect will be described in more detail beiow, starting with preferred
air vessels
used, including containment means for these vessels to allow them to be
charged to
a higher pressure, and then deflector ineans placed within the vest between
the
vessel and the user, and then the regulators, hoses, and respirators used.
-8-
CA 02634651 2008-07-08
The vest I uses a series of interconnected high pressure vessels 10. These
vessels
are illustrated in Figures 3 to 6, and in a preferred embodiment are comprised
of an
entirely non-metal structure to reduce their weight. Vessels 10 are discussed
in
greater detail below. Other metal embodiments of the vessels could also be
used in
the present invention, and this disclosure is not intended to limit the type
of vessel
that may be used within the present vest apparatus. One such vessel that is
contemplated is illustrated in Figure and is made by Luxfer USA Limited.
Pressure vessels 10 are preferably chargeable to extremely high working
pressures,
generally within the range of 4500 - 7500 PSI. For safety, vessels 10 can be
tested
up to 15000 PSI. This is compared to the. prior art air vessels Which are more
typically charged in the 3000-4500 PSI range.
Vessels 10 are preferably made of a carbon fibre epoxy and eomprise body
portion
12 which has a rubber or nylon.coating 14 on Its inner surface and a rubber or
nylon
coating 16 on its outer surface. Carbon Pbre and epoxy were chosen due to
strength
and weight considerations. The shape of the vessel can be a traditional
cylinder, or
cari be more eliiptical (as shown in Figure 5) to more closely fit a user, and
can range
in sizes. Other possible cor,figurations are shown in. Figures 9 and 10.
The inner rubber coating or bladder 14 lis preferably used to provide strength
and to
avoid corrosion. Rubber removes the problem of corrosion associated with
aluminum
liners used currently in the art, and removes the need to tumble vessels in
order to
remove any corrosion. Lack of corrosion should also ensure that the strength
of the
vessel will not diminish from Its original design values.
The inner rubber bladder 14 Is created through the use of a wax module 20, as
can
be seen In Figures 7 and 8. Wax module 20 Includes inlet fittings 22, as
deseribed
below, and is dipped in liquid rubber and allowed to cure. An inner nylon
liner can
optionally be formed by rotomoulding. Aiternatively, an aluminium anodized
liner can
be used instead of a rubber liner.
-g_
CA 02634651 2008-07-08
Once cured, the wax module 20 and inner bladder 14 are mounted on a lathe and
the
carbon filament is wound onto bladder 14. The filament would vessel and wax
module are then heated in an oven at between 200 and 450 degrees Fahrenheit,
depending on the epoxy used to bond the carbon ttiaments. The heating melts
the
wax module 20. The wax is drained away, leaving behind the bladder lining the
interior of core 12.
The core 12 and bladder 14 are then pre#'erablyx-rayed for imperfections and
quality
assurance. Once this is done, the outer rubber layer 16 is created by dipping
the
assembly into liquid rubber. This outer rubber layer 16 provides strength and
prevents hazardous materials from contacting the carbon fibre core. This
protects
against chemicals compromising the Integrity of vessel 10.
In addition to, or instead of, outer rubber layer 16, a composite overwrap can
be
used. The overwrap is best seen in Figure 16. This figure shows pressure
vessel 10
comprised of liner 14 and core 12. L,iner 14 can be a metal or rubber liner,
as
described above. Core 12 can be a carbon fibre / epoxy mixture, as disclosed
above.
Core 12 allows vessel 10 to be filled to its preset pressure without
rupturing.
Liner 14 may not be necessary if core 12 is comprised of stainless steel or
aluminium. These rriateriais provide enough containment to be used without a
liner.
Over-wrap layer 60 is wound over core 12: Over-wrap layer 60 is comprised of a
carbon composite thread that is immersed in a liquid rubber. Preferably the
carbon
composite thread consists of Keviar37' .
The thread and rubberare then filamentwound around thevessei to a
predetermined
thickness. This winding may be done using a computerized lathe in order to
achieve
a uniform thickness about pressure vessei 10. -
4noe the winding Is compiete,'pressure vessel 10 with its over-wrap layer 60
are then
cured to solidify over-wrap layer 60.
-10-
CA 02634651 2008-07-08
The composite overwrap 60 of Figure 16 could also be used on prior art
pressure
vessels to strengthen and protect these Wesseis.
Over-wrap 60 helps mitigate some of the disadvantages that pressure vessels
currently have. In particular, due to the high strength of KeviarTM, present
over-wrap
layer 60 should provide complete containrnent in the case of a failure of the
pressure
vessel. This should therefore protect those around the pressure vessel who
might
previously have been harmed by high vel'ocity fragments created by the failure
of the
pressure vessel. With the overwrap, pressure vessel 10 may be able to be
pressurized cioserto its maximum capacity, allowing more gas to be stored
within the
pressure vessel.
Also, the rubber within the windings creates better impact resistance for
pressure
vessel 10, further protecting it. Rubbor will generally cushion an impact to
the
pressure vessel.
Still further, due to the rubber in the winding, the pressure vessel will be
better able
to withstand caustic environments, creating greater safety for those dependent
on the
pressure vessel.
The open end of each vessel 10 indudes an inlet fitting 22, as can be seen in
Figure
3 and in -grearter detail in Figures 4 and 6. lnlet portion 22 includes iwo
spaced apart
stainless steel plates 24, each with a circular hole 23 in the centre. A
cyiindricai
stainless steel air fitting 26 whose outer diameter fits concentrically within
holes 23
in the steel plates is positioned through holes and the steel plates and air
fitting 26
are then welded together at weldments 25. Steel plates 24 are arrang'ed
paraliel to
each otherwith the gap between them corresponding to the width of carbon fibre
core
12 of vessel 10. When the carbon fibre is formed within this gap, its strength
will
ensure that ftting 22 will not be blown out of vessel 10 due to=the pressures
involved.
This is further tested after the manufacture of the vessel by charging the
vessel to
considerably higher than the rated working pressure and ensuring that vessel
10
does not rupture and air ftting 22 remains in place.
_11
CA 02634651 2008-07-08
The steel plate 24 disposed towards the inner surface of vessel 10 further
includes
two flanges 28 welded to it orformed lntegtally therewith and protruding
substantially
perpendicularly to steel plate 24 and into-vessel 10 and into wax module 20.
This
reduces the likelihood of wax module 20 moving during the filament winding
process
about spindle 21 as most clearly illustrated (n Figure 8 which shows the
flanges
anchored in the wax.
The outer ernd of the steel air fitting 26 is threaded at 27 to allow a cap 30
Figure 8)
to be added to the fitting. Threads 27 canl also be used to secure a second
plate 32
with a nut 34 or a nutflock washer combination to outer steel plate 24 as
shown most
Clearly in figures 3 and 4.
Second plate 32 is shaped and adapted to accommodate regulator body housing 40
of a first stage regulator 44 (Figure 1) as illustrated in Figure 4. As can be
seen frnm
this figure, second plate 32 includes a skirt 33 with holes 37 for screws 36
that pass
through the holes to connect regulator body 40 to second plate 32 for
additional
safety backing up the connection of rege4ator body 40 to threads 27 on fitting
26.
In operation, the vessels are charged cind with reference to Figure 1, air
passes
through first stage regulators 44 attached to the steel air fitting 26 of each
vessel 10.
A series of low pressure lines 46 connect all of the vesseis together through
the use
of stainless "T or "Y' fittings 42, and a low pressure supply line 47 9s
connected to
a second stage regulator 48 on the front of the vest. Lines 46 and 47 are made
from
low pressure f[exble pneumatic hose designed to withstand the pressures under
which the vest is to be tested; or they may comprise metallic hose or a
metallic
manifold. Although pressure vessels 10 can be disposed on both the front and
back
of the vest, its contemplated that in most applications, the vessels will be
confined to
the vesfs back.
Second stage regulator 48 of the present vest apparatus is also selected of
course
to withstand the pressures under which the vessels are to be tested. In a
preferred
embodiment, the second stage regulator will be of a quick ooupling mechanism
type
12-
CA 02634651 2008-07-08
and will allow for the connection of multiple face masks or mouth pieces 49,
i.e., one
for a rescuer and one for the person being resqued. The regulator is placed on
the
vest in a location that allows easy and rapid connection of the face masks.
The
location should also allow a user to easily read a pressure gauge on the
regulator.
In a preferred embodiment the regulator will also have an alarm to signal to
the user
when the pressure falls below a certain level.
A respirator can be designed to easily attach to the second stage regulator.
Various
types of breathing apparatus are contemplated, including a mask to fit over a
users
nose and mouth, a simple mouth piece, a SCUBA respirator or a clear plastic
anti-
fogging hood, such as those currentiy used in -the art.
Due to the high charge pressures of vesseis 1p, the vest apparatus further
includes
several safety features. The first is a containment bag 50 that Is secured to
the
outside of vessel 10. A preferred containment bag 50 is shown in Figure 11.
Containment bag 50 consists of braided steiinless steel aircraft cable 52
woven
around vessel 10 to resemble a fish net, preferpbly on approximately 2.5 cm
squares.
The dimensions of containment bag 50 allow vilrtually no clearance between the
cable
and the exterior rubber bladder 16 or overwraO 60 of vessel 10. This confines
vessel
10, and in the case of an explosion or rupturk any propelled fragments are
limited
in size to the space between the braids. The rubber bladder 16 or overwrap 60
on
the outer surface of vessel 10 should als - act to 'further suppress any
flying
fragments.
Cable *52 of containment bag 50 is held -in place through the use of special
suppression lugs 54, a cross section of one of which is shown in Figure 12,
These
suppression lugs 54 are crimped at strategic; points on cable 52 to hold and
tighten
containment bag 50 in place. As can be seen in Figure 12, each suppr$ssion lug
54
preferably includes three lead cones 56 and a stainless cable end anchor plug
58 to
hold cable 52 within lug 54. The other end oti cable 52 is perrnanently
secured to lug
54, thus creating a closed loop. In the event of a repture of vessel 10, the
-13-
CA 02634651 2008-07-08
compression of cones 56 between plug 58 arld the end of lug 54 will dissipate
energy.
The strength of cable 52, along with rubber biadder 16 or overwrap 60, should
act to
prevent any fragments from escaping from vessel 10. If, however, a fragment
dobs
escape, the present vest apparatus may further be provlded with a novel
deflection
shield 65 disposed between the user and the vessel.
The defection shield is comprised of a materiai-that should withstand and
absorb the
impact of a high speed fragment hitting it. In order to ensure that the weight
and bulk
of the vest apparatus is minimized, it Is furthbr desirable to ensure this
deflection
shield is as thin and, light in weight as possible. This is accomplished
through the use
of a new composite material.
Prior art for carbon composite materials lnciudes the "I-beam" configuration
70 as
shown in Figure 13. This type of core is referred to as "End-Grain-Balsa",
wherein
the vertical portion 71 of the I-beam is balsa wood, and the horizontal
portions 72
i5 above and below the "I" are applied carbon.fibre fabric.
The present deflection shield 65 (shown in Figure 14) comprises carbon fibre
and
high quality epoxy, providing higher impact resistance than most core
materials. For
this Improvement, the balsa wood core of,previous compasites is replaced with
vertical carbon fibre strands 66. This core prtrferably measures between one-
eighth
of an inch to more than two inches in thickness depending upon the level of
protection required. The carbon fibres are cpntinuous-roving, pre-impregnated
tow,
meaning the fibres have been previousiy impregnated in an epoxy-bath with
epoxy
which will begin its cure process with the in#raduction of heat and light.
The core of the present composite is preferebiy created by placing fibres in a
trough
approximately 6-inches wide by .6 inches deep by three feet in length. The
trough
has a plastic liner allowing the fibres to eWly move in the trough. The
finished
material can be cut to a predetermined thickness using known techniques.
-14-
CA 02634651 2008-07-08
The cut slices are placed on a sheet of pre-impregnated carbon fibre fabric
72. A
second layer of the fabric 72 is placed on top of the slice, creating a pure
carbon fibre
core material. The material is then placed in refrigerated storage unfil ready
for
delivery. The present invention further oontemplates using this new core for
other
uses besides deflection plates.
All of the above components are placed within a vest as may be seen in Figure
1.
The vest is constructed in a compartmet-talized fashidn such that the
components
are of sufficient capacity to allow for the easy insertion and removal of the
vessels.
The number of vessels is dependant upon the size of the vessels and the
physical
size of a user's vest, where a child's veSt may only accommodate four vessels
for
example, and an extra large vest may include twelve vessels. Each compartment
further allows a deflector plate 65 to be installed behind the vessel,
protecting the
user in case the vessel explodes or ruptures.
The compartments of the vest are evenly distributed on the back of the vest
but they
can also be distributed on the front and the back if desired.
In one embodiment of the present invention, the vest is constructed to
incorporate a
"quick connect' strap 7 under the buttoCks of a user to prevent the vest from
rising
and interfering with the face mask. The vest may also include a drawstring at
its
bottom which can be used to tighten the bottom of the vest.
Figure 1 shows vest I which includes a Series of vessels 10 located at various
points
along a user's back. Vessels 10 are interconnected with a series of first
stage
regulators 44 and hoses 46 which connect to second stage-regulator 48 on the
vesYs
front.
As described above, second stage regulator 48 is placer! in a(ocation that is
easily
accessible to a user to allow for both the connection of a respirator and to
facilitate
the checlung of the amount of air left in the vessels. This location would
generally be
at chest height and on the front of the garment.
-~~a-
CA 02634651 2008-07-08
The vest can further include storage compartmer<ts into which the
respiratorfits, such
that the respirator can easily be accessed in the case of an emergency_ Other
embodiments envisioned include a storage compartment for a spare mask or hood
allowing the rescue of a victim during an emergency.
The material the vest is made from will depend on its intended application,*
If the vest
is to be used In a fire rescue situation, the material can be the same as that
presently
used in fire fighting clothing, and thus be fire resistant. Conversely, if the
vest is to
be used in mountaineering or marine environments, it can be constructed of a
insulating or waterproof fabric,
The air vest device thus provides a coMpact system with a considerably longer
air
supply than current self contained breathing apparatus on the market. It is
envisioned that the vest may be used ifor a number of applications inciuding:
fire
fighting, oil i9eld and gas plant operatiDns, mining operations, underwater
diving
environments, search and rescue units, irzdustrial chemical processing plants,
NASA,
passenger aircraft personnel, police tadticai units, and anned forces
world,wide_
The above-described embodiments df the present invention are meant to be
iilustrative of preferred embodiments of the present invention and are not
intended
to limit the scope of the present inventson. Various modifications, which
would be
readily apparent to one skilled in the art, are Intended to be within the
scope of the
present invention. The only limitations'bo the scope of the present invention
are set
out in the following appended claims.
-16-
