US3045672A - Face masks for use in the administration of oxygen or other gases - Google Patents

Description

July 24, 1962 F. G. CROASDAILE FACE MASKS FOR USE IN THE ADMINISTRATION OF OXYGEN OR OTHER GASES 5 Sheets-Sheet 1 Filed Nov. 27, 1959 I ATTORUEY Jilly 243, 11962; F. G- CRJQASDAILE' 3,045,672

FACE; MASKS FOR USE IN THE ADMINISTRATION OF OXYGEN OR OTHER GASES 3 Sheets-Sheet 2 P31146612 Now 2171;. 1 959 y MMF/W ATTmeNevs July 24, 1962 F. e. CROASDAILE FACE MASKS FOR USE IN THE ADMINISTRATION OF OXYGEN OR OTHER GASES 5 Sheets-Sheet 3 Filed Nov. 27, 1959 JNVENTOR Fwroelmlr GEQEGE Cm 01:50AM:

ATTORNEYS United States Patent 1 3,045,672 FACE MASKS FOR USE IN THE ADMINISTRATION OF OXYGEN OR OTHER GASES Frederick George Croasdaile, London, England, assignor to Oxygenaire (London) Limited, London, England Filed Nov. 27, 1959, Ser. No. 855,878 Claims priority, application Great Britain July 6, 1959 I 2 Claims. (Cl. 128205) This invention relates to face masks for use in the administration of oxygen and other gases, comprising a bag of flexible substantially gas proof material having an open edge into which the nose and chin of a person may be inserted.

One object of the invention is to provide a simple form of face mask capable of being produced at a cost low enough to justify its being discarded after being used only once, thus avoiding the need for sterilisation after use.

Another object of the invention is to provide a face mask having at least one aperture connecting the interior thereof with the atmosphere, which aperture is closed by means dependent on the supply of gas to the mask, so that the aperture is opened by a failure of the gas supply to ensure free entry of atmospheric air into the mask and thereby avoid discomfort to the user owing to difficulty in breathing. i

The invention consists in the provision of a capsule in the bag of the mask, which capsule is inflated by the gas supplied to the mask and, when inflated, closes a communication between the interior of the mask and the atmosphere.

In the accompanying drawings:

FIGURE 1 is a side view of one form of face mask according to the invention;

FIGURE 2 is a section on the line 11-11 of FIG- URE 1;

FIGURE 3 is a partial elevation of the side of the mask opposite to that shown in FIGURE 1;

FIGURE 4 is an end view looking on the open end of the mask;

FIGURE 5 is a perspectiveview showing the mask of FIGURE 1 in position on a users face;

FIGURE 6 is an explanatory detail view corresponding to part of FIGURE 2;

FIGURE 7 is a partial side View, similar to FIGURE 1, showing a modification;

FIGURE 8 is a side view similar to FIGURE 1, of another form of face mask according to the invention;

FIGURE 9 is a section on the line IXIX of FIG- URE 8;

FIGURE 10 is a partial side view of the mask shown in FIGURE 8, as viewed from the opposite side;

FIGURE 11 is an explanatory detail View similar to part of FIGURE 9; and

FIGURE 12 is a perspective view showing the mask of FIGURE 8 in position on a u-sers face.

Referring to FIGURES l to 7 of the drawings, the mask comprises a bag 10 of thin plastic material such as polyvinyl chloride, open at one edge 11 and closed at its other edges. The material may be transparent, and the drawing illustrates a mask made of transparent material.

The bag 10 is conveniently made from plastic material extruded in tubular form and cut into suitable lengths, one end of each length being shaped to form rounded corners and central projecting tabs 13, and the edges of the material at this end being heat-sealed together to close the end of the bag, the tabs 13 forming a pocket 14 opening into the main part of the bag. At the other end' of the bag the edge of the material is turned inwardly and 'does not form a wall of the capsule 17, and holes 26 3,045,672 Patented July 24, 1962 ice heat-sealed at 15 to the internal, surface of the bag, thus strengthening that edge of the bag, which remains open.

A piece of sheet material 16, similar to that of which the bag is formed, is placed between the tabs 13 and extends some distance into the main part of the bag, the extended portion being heat-sealed to one side of the bag whilst the part which lies between the tabs 13 is sealed to the edges of the latter. This piece acts as a membrane. The piece 16, with one tab and a part of the bag wall, thus forms a capsule -17 inside the bag and pocket. A tubular inlet fitting 18 is heat-sealed to the part of the bag wall which also forms a wall of the capsule, the said fitting being adapted to receive a flexible tube for connecting the mask to a gas container or other source of gas under pressure. In the extended portion of the piece 16 there is formed an aperture '19 connecting the capsule to the interior of the bag 10, the said aperture, as shown, being substantially smaller than the smallest part 21 of the bore of the inlet fitting 18.

A number of apertures 22 are formed in the side of the bag opposite to that to which the inlet fitting 18 is attached.

A strip 23 of spongy material such as expanded plastic is secured to the inner face of one side of the bag at the open end, the strip being shaped substantially as shown in FIGURE 4, so that, when that side of the bag is placed over the nose of the user, the strip fills the hollows between the nose and cheeks. Alternatively, as shown in FIGURE 7, a strip 24 of ductile metal such as soft aluminum may be placed in the fold along the open edge of the bag at one side of the latter, the strip being mould-able to the shape of the u-sers face to keep the edge of the mask in contact therewith. g A stiffening disc25 is heat-sealed to the tab 13 which forming two segments of a circle, are cut in the discs 25 and the tab to which it is secured, the holes connecting the pocket 14 to the surrounding atmosphere.

Two straps 27 are heat-sealed to the bag 10 so as to project from its open edge on the side in which the apertures 22 are formed, and an elastic cord 28 extends between the two straps 27. v

The mask is fitted to the users face by inserting the nose and chin into the open edge of the bag, the side of the latter to which the inlet fitting 18 is attached passing under theusers chin, and the elastic cord 28 is passed round the back of the users head to hold the mask in position. The strip 23 is sumciently deformable to shape itself to fit in the hollows between the nose and checks of the user and, the remainder of the edge of the bag is held against the face by the tension of the elastic cord, so that the edge of the mask fits snugly to the face and makes a substantially gas-tight joint therewith.

If the modified arrangement shown in FIGURE 7 is used, the strip 24 of ductile metal is moulded over the users nose to shape the edge of the mask to the required contour.

Oxygen or other gas to be administered is fed into the mask through the inlet fitting =18, and, since the restriction at the aperture 19 is greater than the restriction at the inlet fitting 18 the gas passing through the capsule 17 into the bag inflates the capsule so as to press the piece 16 against the opposite wall of the pocket 14 and closing the holes 26. Flow of air or gas through the holes 26 is thus prevented, and the user inhales gas introduced through the inlet fitting mixed with a part of the gases exhaled by him into the bag, a proportion of the exhaled gases escaping to the atmosphere through the apertures 22. If the gas supply fails, the capsule 17 is de-inflated, and the holes 26 are uncovered, so that the interior of the mask is able freely to receive atmospheric air through the said holes, and the user is able to breathe without discomfort.

The face mask shown in FIGURES 8 to 12 of the drawings comprises a bag 29 made of thin sheet plastic material such as polyvinyl chloride, the material being first cut to a suitable shape and then folded and joined where necessary by heat-sealing. The bag 29 is open at tively narrow rounded end 3 1. A portion 32 of the sheet material is folded inwardly around the open edge of the bag, and an extension of the folded in portion is provided, comprising a relatively narrow strip like portion 33 and a substantially circular portion 34. The foldedin portion 32 is heat-sealed to the inner surface of the bag at 35 to form a tubular enclosure 36 around the open edge of the bag, and the extension is also heat-sealed to one wall of the bag around its edge to provide, between itself and that wall of the bag, a capsule 37 connected to the tubular enclosure 36 by a passage 38. The tubular enclosure 36 does not extend completely round the edge 30 of the bag, but is interrupted at 39 where the said edge, when the mask is in use, lies over the bridge of the users nose.

A tubular inlet fitting 40, similar to that described with reference to FIGURES l to 3, is heat-sealed to the wall of the bag 29 so as to open into the capsule 37, and an aperture 41, substantially smaller in area than the smallest part of the bore of the inlet fitting at 42, leads from the passage 38 into the interior of the bag. A stiflening .disc 43 is heat-sealed to the wall of the bag opposite to that to which the extension 33, 34 is secured, so as to lie within the area of the capsule 37, and a pair of segmental holes 44 are cut through the disc 43 and the part of the wall of the bag which it covers.

Apertures 45, corresponding to the apertures 22 shown in FIGURE *1, are formed in the same Wall of the bag as the holes 44, and the mask is fitted with straps 46 and an elastic cord 47 for holding it in position on the users face, as already described.

In the face mask shown in FIGURES 8 to 12 the incoming gas not only inflates the capsule 37, but also infiates the tubular enclosure 36 and the passage 38. The inflation of the tubular enclosure 36 provides an adequate seal-between the edge 30 of the mask and the users face,

.one edge 30 and tapers inwardly from that edge to a relaand avoids the need for the spongy material 23 or the ductile metal strip 24 described above. The capsule 37, when inflated closes the holes 44 as shown in FIGURE Thus the edge of the bag is held in substantial sealing relation with the users face, and the holes 44 are closed, so long as the gas is being supplied. Failure of the gas supply, however, causes the capsule 3'7 and the enclosure 36 to collapse. The bag will usually fall away from the face when the enclosure 36 collapses, but, even if it does not, the opening of the holes 44 by the collapse of the capsule 37 allows air to enter and leave the bag freely through those holes, so that the user is not distressed by restriction of air for breathing.

I claim:

1. A face mask comprising a bag of thin flexible, substantially gas-proof sheet material, top and bottom walls, a sealed end, and an open end into which the nose and chin of the wearer may be inserted so that the open end engages the wearers face, means for holding the bag in position on the wearers face, at least one relatively large aperture in one wall of said bag connecting the interior of said bag to the atmosphere, a gas inlet in the other wall of the bag, means for closing said aperture when gas is flowing into said inlet, said closing means comprising, a thin, flexible, gas-proof membrane in said bag, said membrane being attached to said other wall and forming therewith a capsule, said gas inlet communicating with the inside of said capsule, an outlet opening in said capsule leading to the interior of the bag, said opening being of a smaller size than said gas inlet, whereby when gas is applied to said inlet, the flow at the outlet opening will be restricted more than at the inlet so that the capsule will be inflated by the incoming gas closing the aperture in said bag to the atmosphere.

2. A face mask according to claim 1, wherein a disc of flexible sheet material is secured to the said one wall of the bag, said aperture being formed in the part of the said one wall within the area of the disc, a corresponding opening being formed in the disc.

References Cited in the file of this patent FOREIGN PATENTS 220,550 Australia Mar. 2, 1959

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