US 3227159 A
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Jan. 4, 1966 A. BORGIA ETAL 3, 7, 9
MASK FOR THE PROTECTION AGAINST POISON GASES Filed Nov. 5, 1961 4 Sheets-Sheet 1 INVENTORS mum/um b fic m Vuv can! 20 BRAnODvRo rronmsy Jan. 4, 1966 A. BORGIA ETAL MASK FOR THE PROTECTION AGAINST POISON GASES Filed NOV. 5, 1961 4 Sheets-Sheet 2 INVENTORS. ALCIBIADE BORGIA VINCENZO BRAZZODURO BY 166W M W AGENTS Jan. 4, 1966 A. BORGIA ETAL 3,227,159
MASK FOR THE PROTECTION AGAINST PCISON GASES Filed Nov. 5, 1961 4 Sheets-Sheet 3 INVENTOR. ALCIBmnE 1501mm Vnvc N bnuzonuno By #01156 5 M Jan. 4, 1966 A. BORGIA ETAL 3,227,159
MASK FOR THE PROTECTION AGAINST POISON GASES Filed Nov. 5, 1961 4 Sheets-Sheet 4 IN VEN T 0R8.
ALCIBIADE BORGIA VINCENZO BRAZZODURO Y Wm M 3a AGENTS United States Patent 3,227,159 MASK FOR THE PROTECTION AGAINST POISON GASES Alcibiade Borgia and Vincenzo Brazzoduro, both of Rome, Italy, assignors to Ministero Della Difesa-Esercito, Direzione Generale Artiglieria, Rome, Italy, andPirelli S.p.A. Centro Pirelli, Milan, Italy,
Filed Nov. 3, 1961, Ser. No. 149,939 Claims priority, application Italy, Nov. 8, 1960, 19,059/60 Claims. (Cl. 128-141) The present invention relates to a mask for the protection against poison gases and it particularly relates to masks consisting of a rubber facepiece and an interior muzzle, which is also made of rubber and has an approximately frusto-conical shape, this muzzle being attached to the interior of the facepiece and intended to merely cover the wearers nose and mouth.
The masks provided with an inner muzzle keep the circuit of inhaled air separate from that of exhaled air to be discharged into the open and to prevent consequently the mixture of appreciable volumes of the two fluid flows which would obviously damage the breathing function.
Owing to this arrangement the filtered air to be inhaled, i.e. the air coming from the filter, after having entered the mask within the space defined by the facepiece, muzzle and that part of the wearers face which is directly covered by the facepiece, penetrates into the muzzle through an inlet aperture, to be breathed in by the wearer. A check valve is applied either on the inlet aperture of the muzzle or in series with the filter.
During the exhalation the exhaled air is directly discharged into the open through an appropriate valve located more or less in the front portion of the mask, where the facepiece overlies the muzzle. I
To prevent water vapor--whose presence in the mask is also due to the sweat transpiring from the skin of the wearers face-from fogging the eyepiece glasses, the inhalation air passing from the facepiece interior into the muzzle is utilized by making it skim the eyepiece glasses before it enters the muzzle.
In view of this object the muzzle is provided with an aperture for the passage of the air in correspondence with the muzzle top and in the vicinity of the eyepieces so that during inhalation the inhaled air which has already entered into the facepiece through the filter is forced to skim the eyepieces prior to entering the muzzle. Owing to the relatively ample space of the facepiece it is diflicult to produce an efficient flow to skim the eyepieces, in other words a flow of such a rate as to prevent the formation of fogging or at least to eliminate it quickly.
The present invention has for its object a mask for the protection against poison gases in which inhalation passages for directing a rapid stream of fresh air against the eyepieces are formed by cooperating integral portions of the facepiece and muzzle respectively.
In a preferred embodiment of the invention, the facepiece and muzzle have complementary concave portions jointly forming two symmetrical lateral inhalation conduits leading from the filter socket towards the eyepieces, where their outlets are provided with projections integral with the muzzle and constituting bafiles for directing the air flow against the glass of the eyepieces.
The filter socket is located in the chinarea, where the muzzle does not touch the facepiece, and its axis lies in the vertical plane of symmetry of the facepiece.
The necessary complementary shapes of the facepiece and muzzle can be easily obtained during the separate forming operations for the two parts and do not require complex dies. i
Furthermore, in the mask forming the object of the present invention the lateral conduits are easily accessible for inspection and cleaning.
The above described lateral inhalation conduits are also applicable to masks equipped with a sound device, which is necessarily located near the wearers mouth. In this location the muzzle top is in contact with the inner facepiece surface and thus the sound device separates the muzzle chamber from the exterior. The discharge valve is placed laterally to the sound device and is contained in a short tubular connection of the muzzle intended to be inserted into the corresponding circular through socket of the facepiece.
The present invention will be better understood from the following detailed description taken in connection with the attached drawings in which:
FIGURE 1 shows a perspective lateral view of a partially assembled gas mask without sound device and consisting of facepiece and internal muzzle, whose covered parts are shown by a dotted line;
FIGURE 2 shows a lateral perspective view of the muzzle;
FIGURE 3 is a sectional View of the mask assembly taken along its vertical plane of symmetry and including a filter;
FIGURE 4 shows a sectional view of the mask taken along line AB of FIGURE 3;
FIGURE 5 is a lateral perspective view of a gas mask equipped with a sound device;
FIGURE 6 is a lateral perspective view of the muzzle forming part of the mask shown in FIGURE 5;
FIGURE 7 is a sectional View of the mask of FIGURE 5, taken along its vertical plane of symmetry;
FIGURE 8 is a sectional view of this mask taken along line C-D of FIGURE 7.
As shown in the figures, the mask assembly 1 consists of the rubber facepiece 2, and the muzzle 3, which is also of rubber and has approximately the shape of a truncated cone or of a cup, and is arranged in the rearwardly open cavity of the facepiece so that the space within the muzzle is rearwardly open. The muzzle is intended to cover merely the wearers mouth and nose. In its bottom or chin portion, the facepiece 2 has a short tubular projection 4 whose axis is in the plane of symmetry of the facepiece. The tubular projection 4 serves as a socket for the cylindrical filter 41 shown in FIG. 3, but omitted from the other figures of the drawing for the sake of clarity.
At mouth level, the facepiece has a circular opening 5, adapted to contain the discharge valve (not shown in the drawings), and aligned with a similar opening of the muzzle in the vertical plane of symmetry of the mask as will be described in more detail hereinbelow.
The facepiece has two integral eyepiece frames 6 which normally receive lenses (not shown) as is conventional. The facepiece has a rim 7 which is folded back on itself to provide a gas-tight fit with the wearers face; and carries attachments 8 for a harness (not shown).
The facepiece rim 7 has two eyelets which receive respective buttons 9.
The facepiece has two internally convex wall portions 10 which extend from the flaring inner end 4 of the tubular projection 4 to the lower part of the eyepiece frames 6.
As shown in FIG. 2, the lower portion of the muzzle 3 carries an integral nipple 12 which serves as a fitting for the discharge valve (not shown in the drawing). The nipple 12 is normally inserted in the corresponding opening 5 of the facepiece. In its top, the muzzle has a circular passage 13 receiving a check valve 42 (only shown in FIG. 1).
The rim of the muzzle has a portion 11 which is approximately horizontal and conforms to the face con- 3 tours of the wearer, While the remaining rim portion 14 has a downwardly curved shape conforming to the inner surface of the facepiece 1 which it engages.
The valve opens the passage 13, when the pressure in the muzzle space is lower than in the remainder of the facepiece cavity, as during inhaling, and blocks the passage 13 under the opposite pressure conditions prevailing during exhalation.
The muzzle 3 has an elongated, outwardly concave wall portion 15 which defines with the wall portion 10 a conduit parallel to the rim portion 14 and longitudinally coextensive therewith. The conduit communicates with the flaring end 4 of the projection 4. The conduit thus has two lateral branches 18 and 13 connected with each other and the projection 4 at 19.
The muzzle has two projections 16 and 16 which form baffles between the orifices of the branch conduits 18 and 18 and the passage 13 to direct the inhaled air against the two eyepieces before it enters the breathing space in the muzzle 3 through the check valve 42 in the passage 13.
Two eyelets 17 are disposed on the muzzle 3 in symmetrical positions at the junctures of the rim portions 11 and 14. They normally hold the buttons 9 which connect the two lateral rear portions of the muzzle and of the facepiece. This connection between facepiece and muzzle can be quickly released when it is desired to clean the conduits 18, 18'. The facepiece and muzzle are fixedly connected at the discharge valve where the nipple 12 of the muzzle is inserted in the opening of the facepiece. The facepiece and the nipple are sealed against a circular rim of the non-illustrated discharge valve by means of an external ring 5 circling the opening 5.
The air inhaled through the filter 41 enters the connection 19 from the projection 4 of the facepiece 2. It passes through the two lateral branch conduits 18 and 18, and is deflected from below toward the eyepieces 6 by the baflles 16 and 16'. The air then enters the space within the muzzle 3 through the passage 13 and the check valve 42 for breathing by the wearer of the mask.
The exhaled air is discharged from the muzzle directly into the open through the discharge valve in the nipple 12.
The inhalation ducts are easily accessible for inspection and cleaning. When the rim portion 14 of the muzzle is lifted from the rim 7 of the facepiece, and the facepiece is unbuttoned from the muzzle, the latter remains attached to the facepiece only at the discharge valve by means of the external ring 5'. It is then possible to lift the muzzle from the facepiece for cleaning of the inhalation ducts without altering the relative position of In this embodiment, mask 20 consists of the rubber facepiece 21 and the interior muzzle 22, which has an approximately frusto conical shape and protects the wearers nose and mouth. In its lower part, facepiece 21 carries a short tubular body 23 serving as a socket for the cylindrical filter attachment '(not shown in the drawings).
The longitudinal axis of such tubular body lies in the vertical plane of symmetry of the facepiece. At mouths level there is formed a circular through socket 24 adapted to contain the sound device (not shown in the drawings) inserted within a socket in the muzzle, as described in the following. The longitudinal axis of this device also lies in the vertical plane of symmetry of the facepiece. Laterally to socket 24 another circular through socket 25 is formed, for the purpose 'of containing the discharge valve (not shown in the drawings), which is in turn inserted within a similar socket of the muzzle, as it will be described thereafter.
The facepiece has two eyepiece holes 26 for the attachment of the eyepiece glasses (not shown), a peripheral doubled-back rim 27, folded back towards the interior, and the attachments 28 for the harness (not shown in the drawings). It carries in symmetrical position two eyelets (not shown) for the application of the female elements of buttons 29, upon which the corresponding male elements, attached on the muzzle within special eyelets, are applied.
The facepiece presents on its two sides the respective convexities 30 open to the interior, which from the flared internal end 23' of the tubular body 23 extend to the respective eyepieces 26.
The internal muzzle shown in FIGURE 6 also presents in its front part a circular through socket 31 to contain the sound device (not shown in the drawings) and to be contained in turn within the socket 24 of the facepiece. In its upper portion the muzzle presents the circular through hole 32.
Within this hole can be placed the non-return type inhalation valve (not shown in the drawings). However, if found convenient, this valve can also be placed correspondingly to the air inlet in the mask, instead of into said hole.
Laterally to socket 31 a short tubular connection 33 is provided to contain the discharge valve and to be contained in turn within socket of the facepiece.
The peripheral rim of the muzzle has a contour identical to that described in connection with the first embodiment of FIGS. 1-4; in fact it has an upper horizontal portion 35 of varying conformation to fit the wearers nose and cheekbones and a rounded portion 36 to be inserted within the doubled rim 27 of the facepiece.
The muzzle presents externally a semi-circular concavity 34 matching the rounded 36 approximately following the latters extension and conformation. This concavity is complementary to the two lateral convexities of the facepiece which lie opposite to it, and to the flared portion 23 of the inner end 23 of said facepiece socket 23. With the assembly of the two components two lateral ducts 37 and 37 are thus created, being interconnected by the lower space 38.
Correspondingly to the base of the eyepiece glasses the muzzle carries two baflles 39 and 39 to deflect the flow of inbreathed air towards said glasses, after which the air flows into the muzzle via the inlet hole 32 which carries the check valve or not.
The two muzzle eyelets 40, which are symmetrically located in the area where rim meets rim 36, are intended to contain the male elements of buttons 39 conmeeting the facepiece to the muzzle.
The air inhaled through the filter during the phase of inhalation reaches lower space 38 through the lower tubular body 23 of facepiece 21. After flowing through the two lateral ducts 37 and 37' said air reaches the base of eyepiece glasses 26 against which it is directed by baffles 39 and 39', after which it enters the muzzle 22 via the inlet aperture 32, to be inhaled.
During the phase of exhalation the air to be discharged issues from the muzzle directly into the open through the discharge valve housed in the coaxial sockets 33 of the muzzle and 25 of the facepiece.
The sound device is constructed in a manner per se known.
However, it additionally carries a bayonet connection for the possible application of a microphone. A rubber or plastic guard applied to said device permits the use of said mask also in the case of an accidental breaking of the vibrating diaphragm.
Obviously, many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.
What is claimed is:
1. In a gas mask assembly, in combination:
(a) a face piece defining a cavity therein;
(b) an approximately cup-shaped muzzle member in said cavity,
(1) said face piece and said muzzle member each having a front portion, a rear portion, and two opposite side portions connecting the front and rear portions,
(2) said muzzle member defining a rearwardly open space therein and separating a front part of said cavity adjacent said front portion of the face piece from a rearwardly open remainder of said cavity, 1
(3) the front portion of said face piece being formed with an aperture communicating with said front part;
(c) fastening means sealingly fastening said front por-,
tions to each other in abutting engagement;
(d) attaching means releasably attaching said rear portions to each other in abutting engagement;
(e) eyepiece means on a portion of said face piece in contact with said remainder of said cavity;
(f) each side portion of said muzzle member defining an elongated conduit with a corresponding side portion of said face piece, said conduit being laterally closed by said abuttingly engaged front and rear portions, r
(1) said conduits having respective first longitudinal end portions communicating with said front part of, said cavity,;and laterally spaced respective second end portions having respective orifices in said remainder of said cavity facing in a predetermined direction eyepiece means,
(2) said muzzle member being formed with a passage therethrough laterally spaced from said orifices in opposite directions, said passage extending from said remainder of said cavity to said space in a direction substantially opposite to said predetermined direction;
(g) one-way valve means in said passage, said valve means being selectively responsive to a pressure in said cavity higher than the pressure in said space to open said passage; and
(h) exhaust means for exhausting exhaled air said space.
2. In a gas mask assembly as set forth in claim 1, harness means for attaching said face piece to the face of a wearer.
3. In a gas mask assembly as set forth in claim 1, said front portions of said face piece and of said muzzle member being formed with respective aligned openings therefrom through, said fastening means sealingly connecting said front portions at said openingsjand said eXhaust means.
including a discharge valve fitting for mounting a discharge ,valve in sealing relationship with the alignedopenlngs. 1
4. In a gas mask assembly as set forth in claim 1, said side portions of said, face piece and said muzzle member having respective opposite elongated inner wall portions in said conduits, said wall portions extending from said first end portions to said orifices, at least one of said wall portionsin, each conduit being of concavely arcuate section in a plane transverse of the direction of elongation of the conduit.
5. In a gas mask assembly as set forth in claim 4,
said one wall portion being a portion of said muzzle member.
toward said 6. In a gas mask assembly as set forth in claim 1,
baflle means on said muzzle member intermediate said passage and each of said orifices for deflecting a stream of inhaled air from said orifices in a direction away from said passage and toward said eyepiece means.
7. In a gas mask assembly as set forth in claim 1,
said eyepiece means including two eye pieces respectively adjacent said orifices.
8. In a gas mask assembly asset forth in claim 7,
RICHARD A. GAUDET, Primary Examiner.
saidfront portions of said face piece and of said muzzle member being formed with respective aligned openings therethrough, said fastening means being annular and sealingly connecting said front portions at said openings, said exhaust means including a discharge valve fitting for mounting a discharge valve in sealing relationship with the aligned openings; the side portions of said muzzle member having respective wall portions in said conduits, said wall portions being of concavely arcuate cross section in a plane transverse of the direction of elongation of the respective conduits; and baffle means on said muzzle member in said cavity intermediate said one-way valve means and each of said orifices for deflecting a stream of inhaled air from said orifices in a direction away from said passage and toward said eyepieces'.
9. In a gas mask assembly as set forth in claim 1, sound transmitting means for outwardly transmitting sound from said space in said muzzle member.
10. In a gas mask assembly, in combination:
(a) -a face piece defining a cavity therein;
(b) an approximately cup-shaped muzzle member secured in said cavity,
(1) said face piece and said muzzle member each 1 having a front portion, a rear portion, and two opposite side portions connecting the front and rear portions,
(2) said muzzle member defining a rearwardly open space therein and separating a front part of said cavity adjacent said front portion of the face piece from a rearwardly open remainder of said cavity,
(3) the front portion of said face piece being formed with an aperture communicating with said front part,
(4) the front and rear portions of said face piece abuttingly engaging the front and rear portions respectively of said muzzle;
(c) eyepiece means on a portion of said face piece in contact with said remainder of said cavity;
(d) each side portion of said muzzle member defining a conduit with a corresponding side portion of said face piece, said conduit being laterally closed by said abuttingly engaged front and rear portions,
(1) said conduits having respective first end portions communicating with said front part of said cavity, and laterally spaced respective second end portions having respective orifices in said remainder of said cavity facing in a predetermined direction toward said eyepiece means,
(2) said muzzle member being formed with a passage therethrough laterally spaced from said orifices in opposite directions, said passage extending from said remainder of said cavity to said space in a direction of substantially opposite to said predetermined directions;
(c) one-way valve means interposed between said aperture and said space for selectively blocking outward flow of air from said space through said aperture; and
(f) exhaust means for exhausting exhaled air from said cavity.
References Cited by the Examiner UNITED STATES PATENTS 2,300,912 11/1942 Dodge et a1. 128-441 2,381,568 8/1945 Booharin 128-141 2,910,979 11/1959 Shanty et a1. 128-141 3,118,445 1/1964 Norman 128-141 FOREIGN PATENTS 1,028,887 4/ 1958 Germany.