U.S. patent number 3,805,778 [Application Number 05/274,151] was granted by the patent office on 1974-04-23 for a breathing block assembly.
Invention is credited to Richard Garrahan.
United States Patent |
3,805,778 |
Garrahan |
April 23, 1974 |
A BREATHING BLOCK ASSEMBLY
Abstract
A diving head gear includes a form fit mask assembly, a hood
assembly, and a breathing block assembly. Mounting a breathing
block assembly on an oral compartment of the mask assembly ensures
an effortless inhalation and exhalation of gas and, by its unique
configuration, the breathing block assembly blocks and purges any
leaked water from the breathing system. Thusly provided, the head
gear is ideally adaptable to semiclosed and closed underwater
breathing systems to prevent the introduction and transfer of
leaked water which would eventually reach the CO.sub.2 absorption
unit and inhibit its functioning. Because each head gear is
individually tailored to seat on the nonfleshy, bony portions of
the head and face, and only a slight force is required to seal the
mask assembly's interior and no facial pain is suffered. Thus the
head gear is ideally suitable for use during saturation diving or
military undersea operations where it must be worn for long periods
of time.
Inventors: |
Garrahan; Richard (San Diego,
CA) |
Family
ID: |
26796656 |
Appl.
No.: |
05/274,151 |
Filed: |
July 24, 1972 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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99945 |
Sep 21, 1970 |
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Current U.S.
Class: |
128/201.19;
128/201.27; 128/201.28 |
Current CPC
Class: |
B63C
11/14 (20130101) |
Current International
Class: |
B63C
11/02 (20060101); B63C 11/14 (20060101); A62b
009/02 () |
Field of
Search: |
;128/141,142,142.2,147,188,2.08 ;137/512 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
Lancet, Vol. 1 of 1958, pg. 415..
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Primary Examiner: Gaudet; Richard A.
Assistant Examiner: Dunne; G. F.
Attorney, Agent or Firm: Sciascia; Richard S. Johnston;
Ervin F. Keough; Thomas Glenn
Parent Case Text
CROSS-REFERENCE TO A RELATED APPLICATION
This application is a division of now abandoned U.S. Patent
application Ser. No. 99,945 filed Sept. 21, 1970.
Claims
What is claimed is:
1. An assembly for ensuring minimal gas flow resistance and for
expelling leaked water in closed, semiclosed, and open circuit
underwater breathing systems comprising:
a housing block including,
a gas inlet port connected to a source of gas,
an inhale chamber joined to said inlet port, an upper partition of
which downwardly slopes and longitudinally extends across said
housing block and is provided with a plurality of inhale
openings,
a gas inlet port,
an exhale chamber joined to said outlet port, a lower partition of
which downwardly slopes and longitudinally extends across said
housing block in a parallel relationship with said upper partition
and is provided with a plurality of exhale openings, and
a center chamber reaching across said housing block having said
upper partition and said lower partition defining two of its
boundaries and a front wall provided with an orifice and a rear
wall provided with an inhale-exhale opening defining two other
boundaries, said inhale-exhale opening is in fluid communication
with a diver's mouth, the cross-sectional area of said inhale
opening is greater than the cross-sectional area of said inlet port
reducing the velocity of vertically directed said inhaled gas
causing the settling of droplets of said leaked water in said
center chamber for purging therefrom and for further reducing the
inhalation resistance, the cross-sectional area of said exhale
opening is greater than the cross-sectional area of said outlet
port maintaining a reduced velocity of said exhaled gas causing the
settling out of droplets leaked water in said center chamber for
purging therefrom and further reducing the exhalation resistance,
and the downwardly sloping said upper partition defines a sump
portion into which said leaked water drains;
an inhale valve carried in each of said inhale openings to permit
only a vertical, one-way transfer of inhaled gas to said
inhale-exhale opening;
an exhale valve carried in each of said exhale openings to permit
only a vertical, one-way transfer of exhaled gas from said
inhale-exhale opening;
a purge valve unit connected to said sump portion linking said
center chamber and the exterior of said housing block for enabling
selective purging of said leaked water from water from said center
chamber; and
a demand regulator unit connected to a source of reserve gas
secured onto the front of said housing in communication with said
center chamber through said orifice to provide reserve gas upon
failure of said source of gas.
2. An assembly according to claim 1 in which the bottom of said
inhale chamber is provided with an aperture leading to said housing
exterior and said assembly further includes:
a communication unit having a cup-shaped shell containing a
microphone and a remotely extending communications lead, said
cup-shaped shell disposed with its mouth circumscribing said
aperture in a sealed relationship to permit telephonic
transmissions.
3. An assembly according to claim 2 in which the mounting surfaces
surrounding said aperture and said orifice are configured to
accommodate said communications unit and said demand regulator unit
interchangeably to provide a reduced lateral inertial drag and an
improved communications capability when the situation demands.
Description
STATEMENT OF GOVERNMENT INTEREST
The invention described herein may be manufactured and used by or
for the Government of the United States of America for governmental
purposes without the payment of any royalties thereon or
therefor.
BACKGROUND OF THE INVENTION
With the continuing interest in the development of an undersea
technology, the development of reliable, life sustaining systems is
of prime importance. When the performance of tasks and conducting
observations required a diver's being under water for prolonged
periods of time, or at great depths where surface-supplied air was
not practical, self-contained underwater breathing systems of the
semiclosed or closed types were produced. Generally speaking, these
systems operate to recirculate a diver's exhaled breath through a
CO.sub.2 absorption unit which purges the CO.sub.2 from the exhaled
breath, and, to indirectly feed the CO.sub.2 scrubbed gas back to
the diver. An inherent hazard of these systems is that the CO.sub.2
absorbing material becomes nonfunctional upon getting wet. Unless
the exhaled CO.sub.2 is scrubbed from the semi-closed or closed
systems, the diver is exposed to CO.sub.2 excess, leading to
unconsciousness and suffocation. In contemporary systems, water and
saliva from the diver's mouthpiece can and do leak into the
CO.sub.2 absorption cannister located to receive exhaled breath.
One-way valves provided at opposite sides of the mouthpiece allow
the inhalation of gas from a breathing bag and the exhalation of
gas to the CO.sub.2 absorption cannister, but do not block liquids
from the cannister. In addition, divers using the present closed
and semiclosed systems, usually wear a conventional face mask
having a resilient, opaque, tunnel-like sleeve. These masks become
uncomfortable when worn for prolonged periods of time since they
are supported, in part, on a fleshy portion of the face reaching
between the cheekbones and the frontal portion of the upper jaw. To
seal a mask which rests on these fleshy areas, require straps which
pull the tunnel-like sleeve into them. Sufficient tensioning
effects a force fitting of the mask with resulting discomfort,
especially when the mask is worn for long periods of time. Attempts
have been made to obviate this attendant discomfort and water
leakage by constructing a helmet-like arrangement that, in one
instance, encloses the diver's head entirely. With closed or
semiclosed systems, this approach is inherently defective since
dangerous CO.sub.2 buildup is likely. The popular "Jack Brown"-type
face mask, usually employed where a source of surface-supplied air
is available, has been modified for closed and semiclosed circuit
adaptations. But, here again, dangerous CO.sub.2 buildup is an ever
present possibility and facial discomfort, where the mask seats, is
felt. None of the available head gears permits the full realization
of the advantages of self-contained underwater breathing
apparatuses since they all are either inherently dangerous, highly
confining, or manifestly uncomfortable.
SUMMARY OF THE INVENTION
A breathing block assembly is carried on the portion of the shell
adjacent the mouth and directs life-supporting gas vertically as it
is inhaled and exhaled to trap liquids and to purge them from the
system.
A further object is to provide a diving head gear affording
protection to a diver while blocking any water transfer to the
breathing system.
Another object is to provide a breathing block assembly enclosing a
minimal space preventing dangerous CO.sub.2 buildup therein.
Still another object is to provide a diving head gear free of
protuberances.
Another object is to provide a breathing block assembly conforming
contour lying outside of the facial area ensuring a sealed
relationship.
Another object of the invention is to provide a breathing block
assembly ensuring comfort when worn for prolonged periods.
Still another object is to provide a breathing block assembly for
blocking and purging leaked water making it ideal for semiclosed
and closed breathing systems.
Still another object is to provide a breathing block assembly
channeling the inhaled and exhaled gas in a vertical flow for
settling-out moisture droplets entrained in the gas flow.
Still another object is to provide a breathing block assembly
incorporating a slanted chamber in communication with a purge valve
to ensure the drainage and expulsion of leaked water.
A further object is to provide a breathing block assembly ensuring
a reduced inhalation and exhalation resistance to breathing.
Still another object is to provide a breathing block assembly
having a backup-gas system capability.
Yet another object is to provide a breathing block assembly having
a diver communications capability.
These and other objects of the invention will become readily
apparent from the following description when taken with the
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric depiction of the head gear.
FIG. 2 is an exploded view of the breathing block assembly.
FIG. 3a is a sectional view of the breathing block assembly
generally taken along lines 3--3 in FIG. 1 showing gas flow during
the inhale portion of the breathing cycle.
FIG. 3b is a sectional view of the breathing block assembly
generally taken along lines 3--3 in FIG. 1 showing gas flow during
the exhale portion of the breathing cycle.
FIG. 3c is a sectional view of a modified breathing block assembly
generally taken along lines 3--3 in FIG. 1 showing inhaled gas
flow.
FIG. 3d is a sectional view of a modified breathing block assembly
generally taken along lines 3--3 in FIG. 1 showing exhaled gas
flow.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, FIG. 1 shows the head gear
consisting of three main assemblies, those being a face mask
assembly 20, a hood assembly 35, and a breathing block assembly 40.
Taking them in order, the face mask assembly is, in its preferred
form, a sheet of molded material, for example a material possessing
the characteristics of strength, transparency, and ductility, when
heated, as the material commercially available under the trademark,
"Lexan 500."
Breathing block 40 is a significant advance in the art of gas
exchange valve mechanisms and, when employed with the face mask
assembly, markedly increases diver safety and lessens diver
fatigue.
Looking to FIGS. 2, 3a, and 3b, showing a detailed arrangement of
the breathing block assembly, an integral housing block 41 is
machined, or molded, from a strong, lightweight material such as
teflon or aluminum; if the latter is chosen, the housing block and
all of its associated subcomponents are coated with a hard black
anodized finish for protection from the corrosive effects of a
marine environment.
Three longitudinally extending chambers, an inhale chamber 42, a
common inhale-exhale center chamber 43, and an exhale chamber 44
are formed within the block and occupy a substantial portion of its
interior. An inhale port 45, reaches from the inhale chamber to the
outside of the housing block, an exhale port 47 reaches from the
exhale chamber to the housing block's exterior, and an
inhale-exhale opening 46 is formed in an inner wall 41a of the
housing block to provide passageways for the inhalation and
exhalation of gas.
The dimensions and orientation of the inhale-exhale opening
coincide with a diagonally slanted, oral compartment aperture on a
face mask assembly and, when the breathing block assembly is
screwed onto the face mask assembly, via a mounting plate 41b, the
aperture and the opening are aligned. To ensure a sealed fitting
between the breathing block assembly and the face mask assembly,
the outwardly facing configuration of inner wall 41a is
complementary to the outer surface of a face mask assembly of the
oral compartment. Mounting screws 41b', peripherally disposed about
the inhale-exhale opening, are fitted through correspondingly
disposed holes reaching through face mask assembly's outer surface
to compress layered rubber liner 33, when the screws are tightened,
drawing the two assemblies together.
A source of gas and a CO.sub.2 absorption unit, not shown for the
sake of simplicity in the drawings, are joined to the breathing
block assembly by an adapter hose fitting 45a and 47a,
respectively. The fittings are provided with appropriate gaskets
and, optionally, are of several different sizes to interface with
available closed and semiclosed systems.
Looking to FIGS. 3a & 3b, further fashioning of the housing
block calls for shaping a plurality of laterally extending
passageways 48 in a partitioning wall 49 separating the inhale
chamber from the common inhale-exhale chamber. A spider-shaped
valve holder 48a is fitted into each of the passageways and
provides a support for a releasable mushroom check valve 48b
allowing a one-way passage of gas from the inhale chamber to the
common inhale-exhale chamber. Similarly disposed, a plurality of
laterally extending passageways 50 extends through a partitioning
wall 51 separating the common inhale-exhale chamber from the exhale
chamber. Again, spider-shaped valve holders 50a are fitted into
each passageway and releasably supported mushroom check valves 50b
ensure the one-way travel of gas from the common inhale-exhale
chamber to the exhale chamber. After the block's interior has been
shaped milled or molded according to the manufacturing technique
employed and the valve holders and valves are in place, the exhale
chamber is isolated from the surroundings by a top cover plate 52,
provided with an appropriately shaped gasket, screwed onto the
housing block.
A modofication appears in FIGS. 3c and 3c and substitutes a single
valve 48b' in a single passageway 48' in partitioning wall 49' and
a single valve 50b' carried in a single passageway 50' provided in
partitioning wall 51'.
A bottom cover plate 53 and a suitable gasket separate the lower
chamber from the surroundings, but the plate is additionally
configured with a mike opening 53a. The mike opening establishes an
audio communication path from the housing block's interior to an
intercom microphone 54, protected and sealed from the surroundings
by a cup-shaped intercom cover 55. A lead 54a extends from the
intercom microphone through a gland packing, disposed in the wall
of the cup-shaped intercom cover, to relay signals to remotely
located communication equipment. Thus disposed, a speech path, from
the diver, through the common inhale-exhale chamber, through check
valves 48b, the inhale chamber, and, finally, to the intercom mike,
is established. Although the check valves are closed while the
diver is speaking, they do not dampen or render unintelligible his
words.
The bottom cover plate is further provided with a purge valve
opening 53b axially aligned with a purge valve duct 41c. The
opening and duct reach in from the housing's exterior and create a
purging conduit from the lowest portion, a sump portion 43a, of the
common inhale-exhale chamber.
A conventional spring-biased purge valve unit 56 is selected which
consists of a check valve element 56a supported by a valve holder
56b and biased to block the passage of fluid by a biasing spring
element 56c. This valve unit is fitted in the purge valve duct and
by upwardly displacing the check valve element by a manually
actuated plunger lever 56d the selective purging conduit serves as
a passageway between the inhale-exhale chamber and the surrounding
medium.
Particularly shaping the common inhale-exhale chamber to lie with,
approximately, a 10 percent diagonal slant, ensures the drainage
and collection any leaked water and saliva to sump portion 43a and
minimizes the possibility of the water's reaching the exhale
chamber and the following CO.sub.2 absorption unit. As soon as it
collects water is evacuated from the breathing block assembly by
first pushing in on plunger lever 56d, to raise the check valve 56a
from it seat, and then exhaling gas into the common inhale-exhale
chamber. If excessive amounts of leaked water accumulate in the
common inhale-exhale chamber and it starts to become filled
presenting a danger of passing the water to the CO.sub.2 absorption
unit, the hose, joining adapter hose fitting 47a to the CO.sub.2
absorption unit, is pinched closed. Continued forceful exhaling of
gas purges leaked water with little risk of spraying it into the
exhale chamber and onto the CO.sub.2 absorption unit.
Most leaked water enters semiclosed and closed breathing systems
through the interface connecting the systems to a diver's mouth,
usually a mouthpiece, or a conventional type mask assembly. It
naturally follows that leaked water should be blocked, or
accumulated and expelled at this interface. Actuating the purge
valve unit, in a manner above described, dead-ends leaked water
before it gains access to the closed or semiclosed systems. Since
CO.sub.2 absorption units directly receive the exhaled breath in
most systems, and the absorption material deteriorates as moisture
permeates it, the presently configured housing block, having a
longitudinally extending, diagonally slanted common inhale-exhale
chamber ensuring the collection of leaked fluids, substantially
contributes to system reliability and effectiveness.
A further contributing factor to system effectiveness depends from
the relative size and disposition of longitudinally extending
partitioning walls 49 and 51. The walls, by containing a plurality
of laterally extending passageways, greatly increase the areas
through which the inhaled gases and exhaled gases flow with respect
to the areas of the inhale port and exhale port. Since the volume
of gas passing through the breathing block assembly is constant,
upon a given demand by a diver, the velocity of transferred gas is
significantly reduced as the gas reaches the common inhale-exhale
chamber. While this reduced velocity diminishes the inhalation and
exhalation resistance and, therefore, tends to lessen diver
fatigue, the reduction of the gas flow velocity causes gas
entrained droplets of moisture to settle out within the common
inhale-exhale chamber. These settled droplets run down the slanted
chamber and drain into sump portion 43a(assuming that such droplets
find their way into the system "upwind" of the breathing block).
Therefore, by reducing the flow velocity through the breathing
block assembly, moisture coming into the breathing block assembly
via the inhale port is blocked from progressing to the exhale port
and is collected and purged from the system.
Furthermore, on the inhale portion of the breathing cycle, the
inhaled gas is directed vertically, upwardly through laterally
extending passageways 48 and, combined with the reduced velocity,
any gas-carried leaked droplets, being heavier than the gas, tend
more readily to settle out and drain to the sump portion. Exhaled
gas entering the center inhale-exhale chamber, similarly, is
vertically directed and saliva and leaked water coming from the
interior of the face mask assembly fall from the gas flow into the
sump portion, noting the gas flow arrows in FIGS. 3a and 3c showing
the inhale portion of the breathing cycle, and FIGS. 3b and 3d
showing the exhale portion of the breathing cycle.
An additional modification of the breathing block assembly greatly
increases diver safety by allowing an immediate, automatic drawing
of gas from a backup system should the primary breathing system
fail. An emergency port 60, laterally aligned with inhale-exhale
opening 46, is formed in forward wall 41d of the housing block and
the forward facing surface of the forward wall is appropriately
shaped to provide a mounting surface 41e for receiving a demand
regulator unit 61.
The regulator unit incorporates the known features of a
conventional second-stage portion of a widely adopted two-stage
demand regulator. Its principal parts are: a regulator body housing
61a, a diaphragm member 61b, a tilt lever element 61c, and a
fitting 61d joined to a hose 61e extending to a source of backup
gas. If the primary source of gas fails, the diver squeezes shut
the hose carried on fitting 45a and inhales. The inhalation pulls
in diaphragm member 61b unseating the tilt valve to pass gas to the
diver. Optionally, the diaphragm is manually depressed when greatly
increased amounts of gas are required or if rapid purging of the
common inhale-exhale chamber is needed.
Reversing the locations of the demand regulator unit and the
intercom microphone, from that shown in FIG. 6, further improves
the functional nature of the breathing block assembly. Of course,
suitable adapters are provided to fit the demand regulator unit on
the bottom of the housing block through mike opening and to mount
the intercom microphone on the emergency port. With this
arrangement, speech intelligibility rises since the mike is in
direct communication with the diver's mouth and the blind spot
blocking lower, forward vision is reduced since the forward
protrusion of the cup-shaped intercom cover is less than that
presented by the demand regulator unit.
The preferred embodiment of the breathing block assembly is a
rectangularly-shaped, curved block designed to closely fit on the
face mask assembly with a minimum of protuberances, which could
become entangled in cables or marine plant life. Where no
communications capability is required, the microphone is omitted
and the mike opening is sealed shut. When a backup gas supply is
not practical, the demand regulator unit is dispensed. Without the
mike and regulator unit, the essential features of the breathing
assembly are retained and its outline is considerably
streamlined.
All the gaskets, screws, fittings, valves, etc. are standard items
and are subject to routine modification to interface with existing
breathing systems. Because all the elements are subjected to a
harsh, corrosive marine environment, they are selected from
materials either impervious to or resistant to its effects. The
precise manner of connecting the component elements of the
breathing block assembly has not been elaborated on to avoid
belaboring the obvious.
By the unique configuration of the face mask assembly, the
breathing block assembly, and the hood assembly, diver safety and
comfort have risen to a new standard and the limitations imposed by
conventional head gear are overcome.
Obviously, many modifications and variations of the present
invention are possible in the light of the above teachings, and, it
is therefore understood that within the scope of the disclosed
inventive concept, the invention may be practiced otherwise than as
specifically described.
* * * * *