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Publication numberUS3044464 A
Publication typeGrant
Publication dateJul 17, 1962
Filing dateJun 29, 1959
Priority dateJun 29, 1959
Publication numberUS 3044464 A, US 3044464A, US-A-3044464, US3044464 A, US3044464A
InventorsGray Reuben F
Original AssigneeGray Reuben F
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Lower face, high pressure mask
US 3044464 A
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Description  (OCR text may contain errors)

July 17, 1962 R. F. GRAY 3,0

LOWER FACE, HIGH PRESSURE MASK Filed June 29, 1959 2 Sheets-Sheet 1 T0 SEAL PRESSURE DIFFERENTIAL REGULATOR AIR SOURCE VALVE TO MASK 51 '56 I 53 54 CYCLING SPEED 5 VALVE CAM MOTOR CONTROL 4 R. F. GRAY July 17, 1962 LOWER FACE, HIGH PRESSURE MASK 2 Sheets-Sheet 2 Filed June 29. 1959 INVENTOR. REUBEN F. GRAY AGENT The invention described herein may be manufactured by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

The present inventon relates to a lower face, high pressure mask and more particularly to a lower face, high pressure mask for supplying a respiratory pressure to a pilotwhile subjected to accelerative forces of substantial magnitude.

While various'types of masks existing in the art may be said to be generally satisfactory in carrying out the respective vfunctions for which they are specifically designed, none are conveniently adaptable for operation in an environment such as that entertained in the instant invention. The lower face, high pressure mask of the instant invention is normally intended to be operated with apparatus such as that described in patent application, Serial No. 816,650, of Reuben F. Gray for Apparatus for Controlling the Volume of Air and the Distributionof Blood in the Body filed May 28, 1959. In the referenced patent application, there is described apparatus forincreasing human tolerance to effects of accelerative forces by immersing the pilot or subject in a closed constant volume chamber filled with fluid medium approximating the density of blood, such as that of Water. Accordingly, the lowerface, high pressure mask of the instant invention is designed for operation in a water environment, and comprises a substantially rigid member forming the outer portion of the mask proper, which is dimensioned and contoured so as to form a substantially snug closure, embracing the portion of the head extending from above the nose, ears, beneath the eyes, .back of the head, to the neck-shoulder junction. A pneumatically inflatable seal is providecltat each of the upper and lower peripheries of the mask, the pressure within the inflatable seals being such that it exceeds by a constant differential at all times the internal oscillatory pressure of the mask, so that airtight integrity ofrthe closure is assured. Hence, in the manner summarily set forth, the lower face, highpressure mask of the instant invention positively insures for [its airtight integrity while supplying a respiratory pressure dfid ifihd V Patented July l?, 1962 membrane, or eardrum in the auditory canal of the subject. r

An additional object of the invention is the provision of supplying a cyclic respiratory pressure to the interior of the mask concomitantly with the inflation of the pneumatic seals.

The exact nature of this invention as well as other objects and advantages thereof will be readily apparent from consideration of the following specification relating to the annexed drawing in which: I

FIG. 1 is a front elevation partially cut away'view of a preferred embodiment of the lower face, high pressure mask.

FIG 2 illustrates a side view in partial cross section of the lower face, high pressure mask illustrated in FIG. 1,

and

FIG. 3 is a schematic illustration ofa mechanism for cyclically varying the air pressure within both the pneumatic seals of the mask and the mask interior proper, including the periodic concurrent exhausting of carbon dioxide from the interior of the mask.

Referring now to the drawings, wherein like reference characters designate like or corresponding parts throughout the several views, there is shown in FIG. 1, a substantially rigid outer member 11 dimensioned and contoured to accommodate the lower face, neck, and part of the shoulders, as portrayed, from a material such as aluminum, or the like. The outer member 11 of the mask is made in two sections, a lower face frontal section 12 and a back section 13, as more clearly dilineated in the view of FIG. 2, each of the sections being provided on both sides of the mask with flanges 14- andlS. A resilient gasket 16 is interposed between the flanges, although its use is not mandatory to the operation of the mask, as hereinafter will be more readily apparent. The flanges are brought together and maintained in juxtaposition by conventional threaded winged fasteners 17. Each of the fasteners is pivoted at one end thereof by means of a fixedly mounted to the subject in accordance with inventive principles for increasing human tolerance to effects of high level aoceleration. I

An object of the present invention is the provision of a lower face, high pressure mask which positively insures for its airtight integrity while supplying a cyclic respiratory pressure to a subject undergoing acceleration.

Another object is to provide a lower face, high pressure mask in which the infiatable'seals thereof are maintained at a minimum pressure necessary to insure airtight integn'ty of the mask.

A further object of the invention is the provision of a lower face, high pressure mask in which the differential pressure effective to render sealing between the inflatable seal and the interior of the mask is maintained automatically at a constant preselected value,

Still another object is to provide a lower face, high pressure mask in which the carbon dioxide within the mask is held to a minimum.

A still further object of the present invention is the provision of fluid filled ear devices in a lower face, high recluding distortion of the tympanic pressure mask for cuirass employedin the instant invention is arigid, nondeformable membermade from a material such as aluslotted projection 18 and retaining pin 19, as illustrated, and the fastener is thereupon operably accommodated into slots in the flanges. It should be noted that both the front and back section of the mask have no pressure of their own bearing on the subject at the upper: arid lower peripheries thereof when the flanges 14 and 15 are in mated position. The respiratory tube 44 and the exhaust tube 45 are secured to the front section of the mask by threaded couplers 2t and 30, respectively. Flexible washers 46 and 47 coact with couplers 3t} and 20, respectively, to maintain each of the hoses in fixedly secured position. Restraining head straps 21 and 22 are provided to secure the mask in position and operably maintain it in 1a fixed relationshiprelative to the subject with the aid of cuirass 26. Resilient pads 23 and 24 made froma materialsuch as sponge rubber insure for acomfortable head pressure. 7

At the lower extremity of both the front and back sections of the mask'and integral therewith, ridges 25 and 29 are provided, which ridges respectively interlock into a mating groovein cuirass 26, as illustrated in FIG. 2. The

. minum, or the like, as in the exterior construction of the mask} It should be" noted that the use of a cuirass at low accelerative levels is not necessary, but is highly desirable at higherlevels ofacceleration for minimizing body deformation, as discussed in the referenced patent application. Conventional fastening means 27 are supplied. In

" the absence of cuirass 26, 'itshould be understood that the maskis appropriately secured at the armpits and shoulders I by suitable appendage members, or a body harness worn by the, subject. I

Referring next to the internal construction of the lower face, high'pressure mask illustrated in the view of FIG.

integral' assembly with liner 3'4.

2, there is shown an elastic neckpiece 33, made from an elastic material such as rubber so that it readily passes over the head. The flexible inner liner 34 is made from a material such as rubber, rubber sheeting, or the like, and is also designed to be pulled over the head along with the neckpiece 33. At the top periphery of the mask is a pneumatically inflatable seal 31 also made of an elastic substance such as rubber and is encased in a sleeve 32 made from nylon, or other composition having limited yield characteristics. Accordingly, it is the purpose of sleeve 32 to prevent over inflation of seal 31, the latters expansion being thus limited to the stretch characteristics of the sleeve 32. Sleeve 32 is attached to the liner 34 by thermal bonding, or conventional adhesives, thereby holding it in fixed assembly with the liner 34. Pneumatic tube possesses tensile characteristics which are greater than that of seal 31 so that only the seal is capable of expanding. Tube 35- is' constructed integrally with seal selecting a desirable range of pressure differentials. In this manner, a pressure dilierential is obtained which is compatible with the minimum pressure required to maintain efiective sealing. For the exemplary pressures mentioned and assuming the mask interior to be closed to the ambient atmosphere, the pressure'within the mask is 10 p.s.i. while that in the pneumatic seals is 12 p.s.i. above 7 atmospheric pressure.

31 and is detachable from coupler 36 so that it may be conveniently threaded through a hole,,not illustrated, in 9 the top portion of the back section 13 of the mask. At

the lower periphery of themask, the pneumatically infiatable seal is similarly encased in asleeve 3 7. The concentric structure consisting of the sealand sleeve is interposed between the neckpiece 33 and the liner 34, the various elements being all bonded together to form an integral assembly by means of thermal bonding, or high The cyclic variation of pressurized air to the subject is accomplished by electric motor 53 rotating at a speed which corresponds with the respiratory period of the subject. A suitable speed control 54 of a type adapted to control the field excitation'of motor 53 isprovided such that cam 56, which is mechanically coupled to the motor as indicated by the dotted line notation, is driven at a speed comparable to the respiratoryrate of the subject. Cycling valve 57 of a conventional type having suitable aperturesor ports is mechanicallylinked with cam 56 such that actuation of valve S7 causes it to periodically open and close. Exhaust outlet 58 is in communication with the exhaust hose when the cyclic valve is in the open position, and in the closed position of the cycling strength adhesives. Hose 38, comparable in construction 7 to tube 35, is threadable through a hole, as illustrated, in

the back section13 and inserts in coupler 36 for facile attachment. The ends of both the respiratory hose 44 and the exhaust hose 4S entering the mask are bonded to the liner 34. Thus, it is apparent that a closure is provided such that under the influence of pressurized air entering through hose 44, the liner assumes the position illustrated in FIGS. 1 and 2, operably coacting in substantial contiguous relation with therigid non-deformable front section 13 and back section 1 4, which serve as reaction members. V I V Referring'further to the showings in FIG. 1 and FIG. 2, there is portrayed an earpiece 39 of the general type described in patent application, serial No. 789,755 of ,Reuben F. Gray for FuidFilled Ear Muffs filed January 28, 1959, now Patent No. 2,933,086. Filler plug 41-and therfiller tube 42 are provided, asshown, the tube 42 being sealed at the point .where it protrudes through liner 34. In order to insure that proper tension :bears on each of the earpieces 39, a coil compression spring 43 having the flow of air therethrough.

valve, the exhaust exit 58 is blocked to the hose 45. Valve 57 includes manual adjustment provisions for controlling During operation of the respiratory apparatus, the pressure within the mask varies in an oscillatory manner by virtue of the fact that exhaust outlet 58 periodically opens or exposes the interior of the mask to the atmosphere. The partial cyclic eii'luxingof air from the mask through exhaust'outlet 58 causes a lowering of mask pressure. The extent which this pressure decreases is controlled by the manual adjustment provisions of cyclic valve 57, previously mentioned. The lower limit mask pressure is again a function of the contemplated acceleration, and maybe for purposes of illustration, 5 p.s.i. above atmospheric pressure. The decrease mask pressure is reflected at hose 28 supplying pressure to the pneumatic seals through the pressure differential valve 52. Since the latter operably maintains a constant preselected pressure dit- 7 ferential toexist between hoses 28 and 44, the pressure suitable tension'characteristics is interposed between the earpiece 39 and liner 34. The respective ends of the coil spring are fixedly attached in conventional'manner to liner 34 and the earpiece 39,-forming thereby a unitary assembly with the liner. If desired, the entire mechannism may be molded ina rubber compositionto form an Referring next to FIG. 3, there is a schematic illus tration of respiratory apparatusfor supplying a cyclic flow of pressurizedair to both 'the interior of the mask proper, and the pneumatic seals. Source 48 is a compressed air or oxygen bottle. Manually operable valve 49 controls the how of air to regulator 51,'which establishes the permissible upper pressure limit of the air being supplied to pressure differential valve 52 and the intake sealing tube 28. An illustrative upper limit pressure for the air'at the f-junction of pressure differential valve 52 and the sealing tube 28, for example, is 12 psi. above atmospheric pressure; The value of this pressure should be understood as being'a function of the contemplated acceleration, in'

accordance with concepts set forth in the previously men- 1 tioned patent application describing apparatus 'for con trolling the volume of air and distribution of blood in the body. The pressure differential valve 52 is'a' reducer operable to provide a constant preselected pressure diiferential, for example, 2 p.s.i., between the respiratory hose 44 and the intake hose 28, and includes manual provisions for supplied to the pneumatic seals is always greater than the internal pressure of the mask. Hence, in this manner, eifective sealing is provided consonant with considerations of comfort for the subject. Furthermore, it is apparent that the periodic effluxing of air from the mask results in a minimum of carbon dioxide to be accumulated in the mask;

With respect to operational details of the lower face,

"high pressure mask, the upper and lower pneumatic seals thereof are inflated concomitantly with the oscillatory pressure supplied to the interior of the mask. For the exemplary limits of mask pressures set forth, the pressure 7 within the pneumatic seals varies between the upper and pneumatic seals to the limit'permitted by the sleeves 37 and 32 develops the requisite body pressure for rendermg sealing between the inside and outside of the mask. The rigid non-deformable front and back sections of the V mask supply the-necessary restraint or reaction force. 7

Thus, in the manner set forth, the lower face, high pressure mask provides for the airtight integrity of the mask in an'environment in which the-subject while undergoing acceleration is immersed in a closed constant volume chamber filled with a liquid medium. In addition to the maintenance of a sealing pressure consonant with considerations of comfort and that required to render effective sealing, the lower face, high pressure mask cyclically exhausts the interior of the mask so that the accumulation of carbon dioxide is held to a minimum. Moreover, the lower face, high pressure mask of the instant invention embodies fluid filled ear devices as described in the referenced patent application pertinent thereto for precluding distortion of the tympanic membrane in the auditory canal of the subject.

It should be note that while an embodiment has been set forth which is basic in form, other features which do not detract from the spirit of the invention may he supplied. For example, there is disclosed in one of the referenced patent applications appropriate structure for enabling the respiratory apparatus depicted in FIG. 3 to operate automatically at the resiratory rate of the subject. In addition, a bellows including a rotating joint may be incorporated at the neck-shoulder junction in the invention if a greater degree of freedom of movement on the part of the subject is desired. Moreover, while fluid filled ear devices are essential within the concept presently entertained for increasing human tolerance to effects of high level accelerative forces, the use of these devices may be obviated if mixtures of low density gases, such as helium and oxygen in proper proportion, are employed in the respiratory tract.

It should be understood, of course, that the foregoing disclosure relates to only a preferred embodiment of the invention and that numerous modifications or alterations may be made therein without departing from the spirit and the scope of the invention as set forth in the appended claims.

What is claimed is:

1. In combinatioma mask having an upper and a lower periphery dimensioned and contoured to fit over the nose, ears, and encircling the back of the head of the wearer at the upper periphery expo-sing the eyes and top of the head of the wearer and extending to the neck-shoulder junction at the lower periphery, inflatable sealing means secured to the upper periphery of said mask, a pair of fluid filled ear devices, each device being fixedly attached to the mask adjacent and contiguous with the ears of the wearer, inflatable sealing means secured to the lower eriphery of said mask, and respiratory means coupled to said mask.

2. In combination, a mask having an upper and a lower periphery dimensioned and con-toured to fit over the nose, ears, beneath the eyes, and encircling the back of the head of the wearer at the upper periphery exposing the eyes and the top of the head of the wearer and extending to the neck-shoulder junction at the lower periphery, pneumatically inflatable annular sealing means secured 'to the upper periphery of said mask, a pair of fluid filled ear devices, each device being fixedly attached to the mask adjacent and contiguous with the ears of the wearer, pneumatically inflatable annular sealing means secured to the lower periphery of said mask, and respiratory means coupled to said mask.

3. A lower face high pressure mask, comprising in combination, a relatively rigid outer member having an upper and a lower periphery dimensioned and contoured to-fit over the nose, ears, and encircling the back of the head of the wearer at the upper periphery and extending to the neck-shoulder junction at the lower periphery, a continuous relatively flexible inner liner member operably disposed in substantially contiguous relation with said outer member, inflatable sealing means connected to said liner member and said outer member at the upper periphery and the lower periphery of said mask, and means coupled with the inner liner member of said mask for supplyirlrxg a pressurized respiratory fluid to the interior of the mas 4. A lower face high pressure mask, comprising in combination, a relatively rigid outer member having an upper and a lower periphery dimensioned and contoured to fit over the nose, ears, beneath the eyes, and encircling the back of the head of the wearer at the upper periphery and extending to the neck-shoulder junction at the lower periphery, a continuous relatively flexible inner liner member operably disposed in substantially contiguous relation with said outer member, pneumatically inflatable annular sealing means connected to said liner member and said outer member at the upper periphery of said mask, means adapted to be worn about the neck extending therefrom and terminating at the lower periphery of the mask, pneumatically inflatable annular sealing means connected to said liner member and said outer member at the lower periphery of said mask, and means coupled with the inner liner member of said mask for supplying a pressurized respiratory fluid to the interior of the mask.

5. A lower face high pressure mask, comprising in combination, a relatively rigid outer member having an upper and a lower periphery dimensioned and contoured to fit over the nose, ears, and encircling the hack of the head of the wearer at the upper periphery and extending to the neckshoulder junction at the lower periphery, a continuous relatively flexible inner liner member operably disposed in substantially contiguous relation with said outer member, inflatable means attached to the liner member at the upper periphery between the outer'member .and the head to provide for sealing, a pair of fluid filled ear devices, each device being fixedly attached to the inner liner member adjacent and contiguous with the ears of the wearer, inflatable means attached to the liner member at the lower periphery between the outer member and the neck-shoulder junction to provide for sealing, and means coupled with the inner liner member of said mask for supplying a pressurized respiratory fluid to the interior of the mask. a g V 6. A lower face high pressure mask, comprising incombination, a relatively rigid outer member having an upper and a lower periphery diniensionedand contoured to fit over the nose,

back of the head of the wearer at the upper periphery and extending to the neck-shoulder junction at the lower pe-' rip'hery, a continuous relatively flexible inner liner member operably disposed in substantially contiguous relation with said outer member, pneumatically inflatable annular means attached to the liner member at the upper periphery between the outer member and the head to provide for sealing, a pair of fluid filled ear devices, each device being fixedly attached to the inner liner member ad jacent and contiguous with the ears of p the wearer, pneumatically inflatable annular means attached to the liner member at the lower periphery between the outer member and the neck-shoulder junction to provide for sealing, said mask for supplying a pressurized respiratory fluid to the interior of the mask, means coupled with the inner liner member for exhausting the interior of the mask, and means respectively attached to the outer member at the upper and lower peripheries thereof for securing the mask to the wearer.

' -7. A lower face high pressure mask, comp-rising in combination, a relatively rigid outer member constructed into at least two, sections including fastening means therefor, each of said sections being adapted to be brought in mating position with each other and secured by said fastening means in fixed assembly, said relatively rigid outer member in said fixed assembly having an upper and, a lower periphery dimensioned and contoured to fit over the nose, ears, beneath. the eyes, and encircling the *back of the head of the wearer at the upper'periphery and extending to the neck-shoulder junction at the lowerperiphery, a continuous relatively flexible inner liner member operably disposed in substantially contiguous relation with said outer member, pneumatically inflatable annularmeans attached to the liner member at the. upper periphery beears, beneaththe eyes, and encircling the means coupled with the inner liner member of I attached to the inner liner member and said last named and the neck-shoulder junction to provide for sealing,

,a pair of fluid filled ear devices, each device being fixedly attachedto the inner liner member adjacent and contigmask adapted to be worn over the lower face of the wearer and provided with pneumatically inflatable seals for securing airtight integrity of the mask, the combination of said mask, apparatus for cyclically supplying a pneumatic pressure to the interior of said mask at a respiratory rate including a sealing pressure to the pneumatically inflatable seals comprising, a pressurized source of pneumatic fluid, a regulator including a valve connected to the pressurized source of pneumatic fluid, operable to limit the pressure at the output of the regulator at a preselected level, means coupled between the output of the regulator and the mask for reducing by a constantpreselected amount the fluid pressure entering the interior of .the mask, conduit means connecting said pneumatically 'inflatable seals and the output of the regulator, motor 'means including selective speed control means for adjustingthe speed of the motor means for cyclic correspondence with the respiratory period of the wearer of cally linked'with 'said mfotor means and coupled to said mask for periodically exhausting the pneumatic fluid from the interior of said mask, whereby said periodic exhausting is instrumental in operably maintaining cyolic means at the'lower periphery between the outer member 7 said mask, and means including a cycling valve mechanivariation of the pressure within the mask including the pneumatically inflatable seals at the respiratory rate of the wearer.

9. In combination, a mask having an upper and a lower periphery dimensioned and contoured to fit over the nose, ears, and encircling the back of the head of the wearer at the upper periphery exposing the eyes and the top of the head of the wearer and extending to the neck-shoulder junction at the lower periphery, inflatable means secured to the entire upper and lower peripheries of said mask, and respiratory means coupled to said mask.

10. In combination, a mask having an upper and a lower periphery dimensioned and contoured to fit over the nose, ears, and encircling the back of the head of a wearer a t the upper periphery exposing the eyes and the top of the head of the wearer and extending to the neckshoulder junction at the lower periphery, first inflatable means secured to the entire upper periphery of said mask, second inflatable means secured to the entire lower periphery of said mask, and respiratory means coupled to said mask.

References Cited in the file of this patent

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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3200816 *Jun 12, 1962Aug 17, 1965Jr Roscoe G BartlettOxygen supply system
US4971051 *Mar 2, 1989Nov 20, 1990Toffolon Norman RPneumatic cushion and seal
US4989596 *Feb 14, 1989Feb 5, 1991Macris Allen GFace chamber
US5050240 *May 14, 1990Sep 24, 1991Kaiser Aerospace And Electronics CorporationAir cushion helmet support and ventilation system with air pressure regulator
US5117819 *Sep 10, 1990Jun 2, 1992Healthdyne, Inc.Nasal positive pressure device
US6581602Feb 8, 2002Jun 24, 2003Resmed LimitedNasal mask and mask cushion therefor
US6634358May 8, 2000Oct 21, 2003Resmed LimitedNasal mask cushion assembly
US6701927Jun 11, 2002Mar 9, 2004Resmed LimitedFull-face mask and mask cushion therefor
US6871649Dec 6, 2001Mar 29, 2005Resmed LimitedNasal mask cushion assembly
US7069933Nov 12, 2003Jul 4, 2006Resmed LimitedBreathing mask and mask cushion therefor
US7198079Sep 9, 2003Apr 3, 2007Tvi CorporationLiquid delivery system of gas mask
US7243651Sep 7, 2004Jul 17, 2007Resmed LimitedCushion and mask therefor
US7273052 *Dec 11, 2003Sep 25, 2007Tvi CorporationPneumatic sealing system for protection masks
US7458390Dec 21, 2005Dec 2, 2008Tvi CorporationBreath controlled air inlet for blower
US7469699Sep 3, 2004Dec 30, 2008Tvi CorporationThin profile air purifying blower unit and filter cartridges, and method of use
US7690379Jun 1, 2004Apr 6, 2010Branch, Banking and Trust CompanyPressure indicator for positive pressure protection masks
US7950392Jul 13, 2007May 31, 2011Resmed LimitedCushion and mask therefor
US8056561May 12, 2006Nov 15, 2011Resmed LimitedFull-face mask and mask cushion therefor
US8522783May 16, 2011Sep 3, 2013Resmed LimitedCushion and mask therefor
US8584676Nov 19, 2003Nov 19, 2013Immediate Response TechnologiesBreath responsive filter blower respirator system
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Classifications
U.S. Classification128/205.25, 128/206.26
International ClassificationA62B18/00
Cooperative ClassificationA62B18/00
European ClassificationA62B18/00