GB2059782A

GB2059782A - A breathing half-mask for once only use

Info

Publication number: GB2059782A
Application number: GB8030438A
Authority: GB
Original assignee: Draegerwerk AG and Co KGaA
Current assignee: Draegerwerk AG and Co KGaA
Priority date: 1979-09-25
Filing date: 1980-09-19
Publication date: 1981-04-29
Also published as: FR2465491A1; DE2938720A1; FR2465491B1; GB2059782B; SE8004864L; DE2938720C2; SE439247B

Abstract

A breathing half-mask for once only use consists of a material which may exert filtering action in a form which ensures that it fits over the nose, the cheeks and the chin of the user with sufficiently free space around them, and of head bands which are secured to the edge. In a preferred construction, the mask consists of a mask body (1) formed of a pleated plastics non-woven fabric, and a sealing member (2) extending towards the interior of the mask having an inside edge (8) and consisting of the same material, which are connected together at their peripheries, thereby increasing the rigidity and forming a support (12) for the head bands (not shown). A reinforcing member (3) having an inside edge (11) and consisting of hard-elastic plastics is preferably disposed between the sealing member and the mask body and the three components are connected together by adhesion or welding. <IMAGE>

Description

SPECIFICATION Breathing half-mask for once only use This invention relates to a breathing half-mask for once only use.

Breathing half-masks for once only use have the advantage that they do not require servicing, for example cleaning and disinfecting, after use. However, once only use requires that the masks be capable of being produced economically yet still be capable of performing their protective function, which, in the case of industrial use, consists of preventing penetration of harmful substances into the respiratory organs of the wearer, and, in medical use, consists of preventing the passage to the patient of germs exhaled by the wearer. This necessitates a simple form of construction and possibility of machine production.

A known protecting breathing mask for medical and veterinary use and for use in working areas in which a dust hazard exists is described in German Gebrauchsmuster No. 7,631,132. This mask consists of a bellows of filter material folded in zig-zag form with five to eight double folds. Two endless elastic retaining bands of a width of 4 to 6 mm are secured by stapling or stitching to the bunched fold ends on the upper and lower outside surfaces of the bellows assembly. The uppermost double fold, which then lies over the nose, is made more rigid by an aluminium strip adhesively secured thereto. Before use, the bellows is fully extended and fitted over the respiratory organs.The bunching of the bellows assembly, with the retaining bands being close to the ears, is intended to prevent the stretched-out folds from bulging out and thus to guarantee an airtight fit The aluminium strip is intended to seal the mask against the root of the nose. A disadvantage of this mask is that it lacks a defined operational form. It is doubtful whether the upper edge, which is in any case uncomfortable, will adapt itself to various facial forms and provide an adequate seal. For medical use, the latter requirement must always be completely satisfied for protection of the patient.

Another known single-use breathing mask is described in German Offenlegungsschrift No.

2,717,968. This mask consisting of a multi-layered material which acts as a filter for dust and smoke.

The main body is so shaped that a comfortable close fit over the nose, the cheeks and the chin of the user is obtained, while a sufficiently free space is present around these parts in the interior of the main body.

The edges of the layers of the filter material form a border around the main body while combining to form a seal. Head bands are secured to the border, which has projections for this purpose. The cupshaped main body is produced from a flat sheet of material which filters dust and smoke and which is pressed into the form of a mask in a heated mould cavity by means of a die. The border is thereby simultaneously formed and the head bands are thereafter secured thereto. Above the uppermost nose portion of the main body, an angular nosepiece, preferably made of metal, is secured by means of a hot-melt bonding agent. After the mask has been put on, pressure is applied to the nosepiece so that it holds the mask above the nose. In this known breathing mask, the filtering surface is formed only by the external form of the main body.

Consequently, when a material having sufficient filtering ability is used, the resistance to breathing is too high. Conversely, the resistance is insufficiently effective when a coarse-pored material is used. The narrow edge, which is substantially perpendicular to the skin of the face, is very uncomfortable, while the sealing effect is insufficient.

According to the present invention, there is provided a mask for fitting overthe nose, cheeks and chin of the wearer, the mask comprising a mask body made of a pleated non-woven plastics material fabric and a sealing member made of a non-woven plastics material fabric, the mask body and sealing member being joined to one another along their peripheries to form an edge along which the mask is sealed against the face of the wearer in use of the mask. Preferably, a reinforcing member made of a resilient plastics material is disposed between the mask body and sealing member, the mask body being joined to one face of the reinforcing member and the sealing member being joined to the other face of the reinforcing member.

The present invention also provides a mask for fitting over the nose, cheeks and chin of the wearer, the mask comprising a mask body made of a pleated non-woven plastics material fabric and a reinforcing member made of a resilient plastics material, the mask body and reinforcing member being joined to one another along their peripheries to form an edge along which the mask is sealed against the face of the wearer in use of the mask.

The invention provides a breathing half-mask for once only use, which does not have the known disadvantages. It is intended to be light and comfortable to wear and nevertheless to guarantee, when used in industrial and medical fields, a good and reliable filtering action. A pre-requisite forthis purpose is that the configuration of the mask and its dimensional stability are always maintained under stress and when thoroughly moistened by exhaled air or by perspiration. This applies more particularly to that region of the mask which bears against the face of the wearer, in particular against the bridge and root of the nose. This is clear from the fact that many known masks consisting of filtering and therefore generally soft materials are provided with a metal clip at the nose portion. Single use necessitates the possibility of economical production.

According to the invention, the mask body is formed by pleating a filtering plastics non-woven fabric and is then deformed into a shape covering the nose, mouth and chin. An inwardly protruding sealing member or lip is secured, e.g. by welding or adhesive bonding, to the sealing line, i.e. to the sealing edge, which preferably consists of the same material. The sealing edge may be made somewhat broader in order to produce good dimensional stabil itywiththe non-woven material hardened atthis point. The dimensional stability obtained thereby and by means of the protruding sealing member is improved if a somewhat harder non-woven material is used for the sealing member.

Avert much higher dimensional stability is obtained if there is disposed in the edge between the two non-woven fabrics, i.e. between the edge of the mask body and the sealing member, a reinforcing member consisting of a resilient (or hard elastic or elastically stiff) plastics material, for example polyvinyl chloride, polymethacryl ester, polymethac rylate or cellulose acetate, which is simultaneously welded or bonded thereto. By means of this reinforcing member, which may be brought into a form corresponding to the sealing line on the face, for exam ple by deep drawing or extrusion, before the welding or adhesive bonding to the mask body, the seal at the bridge and the root of the nose is improved.

The three-layered sealing edge of the mask is used to hold head bands. The band holders may consist either of the three-layered edge or merely of a protecting portion of the reinforcing member In this way, the tensile force is transmitted better to the entire sealing edge without producing any deformations which might affect air-tightness, even if the mask body becomes moist. This material, which is consolidated by the welding operation orthe adhesive bonding, may equally well be formed with a number of apertures so that the bands are movable.

When the reinforcing member is used, the third layer, i.e. the inwardly positioned sealing member, may be omitted, but it acts as an additional sealing means and makes the mask more conformable and better fitting.

In one method of manufacturing a mask according to the invention, a non-woven plastics material fabric is pleated as a web and the pleats are laterally fixed by welds, the mask body is shaped by means of a tool consisting of a hollow mould and a die by ironing with deformation of the sealing edge, the blanks for the sealing member, the reinforcing member and the mask body are laid one above the other with the aid of centering means and are welded at the sealing edge, and the mask is then cut out. This method, together with the simple and cheap individual parts, ensures economical production. The same applies to the production of the mask in which component parts are joined by adhesive bonding.

By reason of the possibility of once only use, it is not only easy for the wearer to satisfy requirements as to hygiene, butthe wearer also avoids the need for tedious and unreliable disinfection and the subsequent sterile storage until further use.

For a better understanding of the invention, reference will now be made, by way of example, to the accompanying drawings in which: Figure 1 is a view from the front of a mask according to the invention (with the head bands thereof omitted); Figure 2 is a view from the side of the mask shown in Figure 1; Figure 3a shows one form of the band holders of the mask of Figure 1; Figure 3b is a sectional view taken along line X-Y of Figure 3a; Figure 3c is a sectional view, similar to that shown in Figure 3b, showing another form of the band hol ders of the mask of Figure 1; Figures 4 and 5 each show other forms of the band holders of the mask of Figure 1; and Figure 6a, band c illustrate a method of making the mask of Figure 1.

The mask shown in the Figures consists of a mask body 1, a sealing member 2 within the interior of the mask body 1, and a reinforcing member3 disposed between the mask body 1 and the sealing member 2.

The mask body 1, the sealing member2 and the reinforcing member3 are joined together.

The reinforcing member3 has a round aperture 11 and a nose aperture 9, and the sealing member 2 has a round aperture 8 and a slit 10. As is shown, the aperture 11 is largerthan the aperture 8.

The material of the mask body 1, which acts as a filter medium, is a non-woven plastics material fabric. As shown in Figure 6a, a blank 5 of the fabric, which is in the form of a web, is pleated to form longitudinal pleats 6 which are fixed by lateral welds 7. As shown in Figure 6a, the pleated blank 5 is shaped into the form of the mask body 1 in an apparatus consisting of a hollow mould and a die.

This is effected by means of an ironing operation in which the pleats 6 are displaced. The non-woven fabric is not thereby modified (i.e. it is not stretched, for example). At the top and bottom, small folds 19 are made in order to produce rounded shape. At the same time, a sealing edge 21 is pre-formed. As shown in Figure 6c, an aperture 11 is cut in a blank of the reinforcing member. Similarly, an aperture 8 and slit 10 are cut in a blank of the non-woven plastics material fabric. The three blanks are placed one upon another and welded together in a further apparatus, and the finished mask is then cut out.

The reinforcing member 3 consisting of a resilient plastics material such as those listed above, unites the mask body 1 with the sealing member 2.

The reinforcing member 3 has laterally projecting band holders 12 for securing the head bands 4. As shown in Figures 3a, band c, the band holders 12 may have longitudinal slots 15 parallel to one another for looping-in head bands 4. As shown in Figure 4, the band holders 12 may have apertures with a tab 16 for buttoning-on head bands 4 provided with holes 17. As shown in Figure 5, the band holders 12 may have lateral slots 18 for engagement of endless head bands 4 made of rubber, which may be for example, remnant strips. As shown in Figure 3b, the band holders 12 may instead be formed of three welded layers, i.e. of the edges of the mask body 1,the sealing member 2 and the reinforcing member 3.

The reinforcing member3 ensuresthatthe sealing member 2, and thus the mask as a whole, is pressed with sufficient force against the bridge of the nose and the chin of the wearer. The sealing member 2 bears on the face along the inner edge of the large aperture 11 and the nose aperture 9, so that sealing between the mask and the face is good. The elasticityofthe reinforcing member3 also ensuresthatthe seal is retained during movement of the face.

The mask shown in the Figures can be machine produced. To enable the blanks for the mask body 1, the sealing member2 and the reinforcing member3 to be reliably introduced into the machine, they may have like centering means 20, as shown in Figures 6a, bandc.

Claims

1. A mask for fitting over the nose, cheeks and chin of the wearer, the mask comprising a mask body made of a pleated non-woven plastics material fabric and a sealing member made of a non-woven plastics material fabric, the mask body and sealing member being joined to one another along their peripheries to form an edge along which the mask is sealed against the face of the wearer in use of the mask.

2. A mask as claimed in claim 1, wherein a reinforcing member made of a resilient plastics material is disposed between the mask body and sealing member, the mask body being joined to one face of the reinforcing member and the sealing member being joined to the other face of the reinforcing member.

3. A maskforfitting overthe nose, cheeks and chin of the wearer, the mask comprising a mask body made of a pleated non-woven plastics material fabric and a reinforcing member made of a resilient plastics material, the mask body and reinforcing member being joined to one another along their peripheries to form an edge along which the mask is sealed against the face of the wearer in use of the mask.

4. A mask as claimed in claim 2or3, wherein the reinforcing member extends outwardly beyond the periphery of the mask body and, if present, the periphery of the sealing member, the outwardly extending portion ofthe reinforcing member being provided with means for holding head bands.

5. A mask as claimed in claim 4, wherein the means for holding the head bands comprises, for each end of the or each head band, three parallel slots in which the end can be looped.

6. A mask as claimed in claim 4, wherein the means for holding the head bands comprises, for each end of the or each head band, an aperture provided with a tab onto which the end of a head band provided with holes can be buttoned.

7. A mask as claimed in claim 4, wherein the means for holding the head bands comprises, for each end of the or each head band, a pair of lateral slots for engagement of an endless elastic band.

8. A mask as claimed in any of claims 2 to 7, wherein the reinforcing member includes an aper tureforthe nose of the wearer.

9. A mask as claimed in any of claims 2 to 8, wherein the reinforcing member includes a deformed portion adapted to the nose of the wearer.

10. A mask as claimed in any of claims 1 to 9, wherein the mask body and sealing member, or the mask body and reinforcing member, or the mask body, sealing member and reinforcing member, as the case may be, are joined to each other by welding

11. A mask as claimed in any of claims 1 to 9, wherein the mask body and sealing member, or the mask body and reinforcing member, or the mask body, sealing member and reinforcing member, as the case may be, are joined to each other by adhesive bonding.

12. A mask as claimed in any of claims 1 to 11, the mask having been made by a method comprising pleating a non-woven plastics material fabric in the form of a web and laterally fixing the pleats by means of welds; shaping the pleated fabric to form the shape of the mask body by the use of a hollow mould and die; placing the resulting blankofthe mask body, and blanks of the sealing member andl or of the reinforcing member, one upon another and joining them together along the periphery of the mask body; and cutting out the mask from the welded blanks.

13. A mask as claimed in claim 1, substantially as hereinbefore described with reference to, and as shown in, Figures 1,2, 3a and 3b, or Figures 1,2, 3a and 3c, or Figures 1,2 and 4, or Figures 1, 2 and 5, of the accompanying drawings.

14. A mask as claimed in claim 12, the mask having been made by a method substantially as hereinbefore described with reference to Figures 6a, 6b and 6c of the accompanying drawings.