CA1185500A - Disposable respirator - Google Patents

Disposable respirator

Info

Publication number
CA1185500A
CA1185500A CA 406442 CA406442A CA1185500A CA 1185500 A CA1185500 A CA 1185500A CA 406442 CA406442 CA 406442 CA 406442 A CA406442 A CA 406442A CA 1185500 A CA1185500 A CA 1185500A
Authority
CA
Grant status
Grant
Patent type
Prior art keywords
respirator
webs
face
joining
materials
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
CA 406442
Other languages
French (fr)
Inventor
Joseph Z. Zdrok
Joseph A. Maisano
James J. Krusas
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
American Optical Corp
Original Assignee
American Optical Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Grant date

Links

Classifications

    • AHUMAN NECESSITIES
    • A41WEARING APPAREL
    • A41DOUTERWEAR; PROTECTIVE GARMENTS; ACCESSORIES
    • A41D13/00Professional, industrial, or sporting protective garments, e.g. garments affording protection against blows or punches, surgeon's gowns
    • A41D13/05Professional, industrial, or sporting protective garments, e.g. garments affording protection against blows or punches, surgeon's gowns protecting only a particular body part
    • A41D13/11Protective face masks, e.g. for surgical use, or for use in foul atmospheres
    • A41D13/1107Protective face masks, e.g. for surgical use, or for use in foul atmospheres characterised by their shape
    • A41D13/1123Protective face masks, e.g. for surgical use, or for use in foul atmospheres characterised by their shape with a duckbill configuration

Abstract

DISPOSABLE RESPIRATOR

ABSTRACT OF THE DISCLOSURE
A foldable respirator fabricated from a continuous multilayered web of its composite materials and offering optimum edge-to-face seal with avoidance of inhalation collapse during use.

Description

--1~

D I S POSABI.E RES PI RATOR

BACKGROUND OF THE INVENTION
Field of the Invention This invention relates to disposable respirators more particularly of the foldable type which offer protection against pneumoconiosis and fibrosis producing contaminants.
Description of the Prior Art:
It is important to seek the protection of one's respiratory system with a respirator when subjected to unpleasant or noxious environments. However, respirator wearing comfort, convenience of carrying and freedom from maintenance are paramount to overcoming the commonly encountered resistance to use.
In addition to a further-desire for co~pactness, lightness of weight and comfort of face fit, a wearer's ready acceptance of a particular respirator design requires minimal resistance to breathing through the face piece and avoidance of heretofore encountered "hot and clammy" breathing atmosphere within the face piece. This, in turn, requires adequate spacing of the face piece around nose and mouth and avoidance of collapse during inhalation.
Heretofore, the abo~e has been best attended to with rigidly cupped and/or frame supported respira~or structu7res of types exemplified ~y U.S. Patents Des. 248,497 and 3,521,630. These, however, suffer the disadvantages of costly manu~acture, ungainliness in storage and carrying by workers as well as a vulnerability to . damage by crushing, particularly in the case o~ the type of structure illustrated in U.S. Des. 2~8,497.
Frame supported structures, on the other hand, require periodic cleaning of the support structure, tedious .

~ 5~
filter replacement a~d provision for clean storage of the devices between times of use~
In view of the above, the more easily carried foldable and disposable pocket respirator is attractive 5 to workers and suppliers alike. However, such devices of which those of U.S. Patents Nos. Des~ 249,072 and 4,248F220 are exemplary, lack the effectiveness of the c1lp-formed or frame-supported devices. In particular, they lack the ease of application to .. -~ .
- 10 the face, comfort of final fit, resistance to collapse ~ and air filtering capability of multiple layer filtering - systems. Additionally, complicated plea~ing, stitching~
riviting and other assembly procedures needed to produce prior art folded respirators render them relatively difficult and costly to produce.
In view of the foregoing, an objective of ~~ the present invention is to provide improvements in folded respirators and method of making same.
Another object is to provide for simple and economical mass production of the respirators, more particularly by use of a continuous multiply layered web of disposable materials~
Still another object is to provide an end product offering exceptional face-fitting and breathing comfort with optimum air filtering efficiency.
Other objects and advantages of the invention will become apparent from the following description when taken in conjunction with the accompanying drawings.

IN THE DRAWINGS
~ig. 1 is an illustration, in pèrspective~
of a preferred embodiment of the invention;
Fig. 2 ;s an enlarged cross-section taken along line 2-2 of Fig. 1;

. ,~

. _ .

Fig. 3 is a fron~ elevational view o~ ~he respirator of Fig~ 1 shown in a position of use;
Fig. 4 is a side vlew of the respirator of Figs. 1 and 2 also shown in a position of use;
. . ~ .
Figs. 5 and 6 are diagrammatic illustrations of a cross-section of a materials assembly used in practice of the invention;
Fig. 7 is a plan view of the Figs. 5 and 6 assembly following a first heat sealing operation of the invention;
Fig. 8 is a cross-sectional view taken along line ~-8 of Fig. 7 wherewith results of the heat sealing operation are-illustrated in diagrammatic fash;on, Fig. 9 is another plan view of the Figs~ 5 and 6 assembly illustrating an additional heat sealing operation of the illustrated process; and ~ig~ 10 is a cross-sectional view taken along line 10-10 of Fig. 9O
.. , ~0 DESCRIPTION OF T~E PREFERRED EMBODIMENTS
.
Referring to the drawings, respirator 10 ~Fig~ 1~
is shown flat, i.e. folded, for convenience of packaging, shipping and/or carrying in a worker's pocket as a spare or when not needed on the ~ace. In Fi~s. 2 and 3, respirator 10 is opened and illustrated in a position of use.
Body 12 oE the respirator comprises superimposed top and bottom webs 14 and 16, of layered air-filtering material. Each web preerably includes an outer shell 18, an intermediate lofty filter medium 20 a~d inner scrim 22. The layers are edge or rim seaied together leaving the intermediate matPrial generally uncompressed and highly efficient in its intended -.
.~
~ . .

s~r)~
air-filtering function. Ribs 24 and 2~ formed by material heat sealing may be provided for body 12 shape retention and assurance reinforcement against collapse during inhalation.
Essential to the accomplishment of secure edge sealing of webs 14 and 16 is a selection of materials which have heat-sealing compatibility.
The following are exemplary:
Outer shell structure 18 requires a material capable of wi~hstanding direct handling abuses but having a porosity permitting easy passage of inhaled - and exhaled air. A mesh of polyester fibers with a heat-sealable binder of polyvinyl chloride may be used. Suitable commercially available products are Stearns and Fos~er Type 4144X or W3499 polyes~er non-woven media supplied by The Stearns and Foster Company of Cincinnati, Ohio, USA and Union Wadding 7 oz.
polyester non-woven media supplied by Union Wadaing Company of Pawtucket, Rhode Island, USA.
Inner filter medium 20, pre~erably maintained in a somewhat lofty sta~e between lines of hea~ seallng may comprise a random gathering of polyester fibers with a thermoplastic medium. Vinyon and/or viscose fibers may be used. A suitable commercially available - 25 product is Riegel Stype S-03059-1 polyester 100 gram/sq.
meter supplied by Riegel Products Corporation of Mil~ord, New Jersey, USA.
Scrim ~ which engayes the ~ace when worn may oomprise a soft highly porous web or mesh of polypropylene. A suitable commercially available product is Snowpro Style #440-0827 polypropylene filter media .8 oz/s~. yd. supplied by Snow Filtration Company o~ Cincinnati, Ohio, USA.
It should be understood that in the combination .

. . .

~ S5~3 : - of materials selected for webs 14 and 16, those happening to be less responsive than others to sealing together may, nevertheless, be readily ~oined to the others having greater response to dielectric or other forrns of heatirlg.
While edge and other heat sealing ope~ations of the present invention are preferably performed .. dielectrically with conventional apparatus well known -;- to the artisan and not re~uiring discussion herein, it should be understood that electrically or otherwise heated dies and the like, with applied pressure and/or ultrasonics.may also be used Furthermore, edge and/or rib sealing of the present respirator structure .
- may employ adhesives if necessary or desired. Sti~ching~
., 15 which is presently ccnsidered least desirable, may .
. nevertheless be employed throughout or in partial assembly of:the respirator~ -. It should be understood that wh;le the abo~e .. ; mentioned materials and sources of supply will provide ., 20 for successful practice of the invention, this information is not to be taken as limitive or in any sense restrictive to the invention. Those skilled in the art will readily appreciate that various other commercially available or specially prepared synthetic and/or ~ 25 natural fiber mediums, webs, meshes, shells or scrims may be obtained or produced and used.
Referring more particularly to the respirator 10 shape, it can be seen from Figs. 1, 2 and 3 that special curvilinear edge contours 28 and 30 have - 30 been selected to provide a comfortable substantially -. airtight seal about the nose, mouth and chin when respirator 10 is positioned ~or wearing and held by elastic headbands 32, 34. Remaining edges may be rectilinear and angularly related as illustrated, ~ . , ~ ..3.~55'~
right angularly related or comprise onl~ two acutely angled sides or a sin~le semicircular side connecting opposite ends of edges ~8 and 30.
An attached malleable chevron 36 ~acilitates fitting and maintainin~ fit of the respira~or over th~ nose. The chevron may be formed of a strip of aluminum or its equivalent and cemented in place.
By pressing the chevron toward ~he nose after application of the respirator ~he a~oresaid nasal sealing may be readily accomplished. While the nose area is-usually considered the most difficult to fit and seal it can be readily attended to in this manner.
As illustrated in Figs~ lt 2 and 3, respirator 10 may be quickly and-efficiently converted from its folded, pocket carrying con~iyuration r~ig~ 1) to a relatively rigid cupped con~iguration for wearing by opening edges 28 and 30, placing the opening over ~he nose, mouth and chin~ slipping headbands 32, 34 ~0 over the head and shaping chevron 36 against ~he _ nose.
- Ri~s 24 and 26 lend rigidity to the opened structurer assist in the prevention of collapse of respirator body 12 during inhalation and retain ample ~~ 25 space between nose, mouth and respirator inner walls to avoid undue overheating and/or "clamminess" of the internal breathing atmosphere.
A pre~erred manner of constructing respirator 10 is illustrated diagrammatically in Figs~ 5-10. Therein a mass production technique, using a continuous supply (strip 42) of ma~erials, is demons~rated. I~ should be clear, however, that this technique can be geared to large or small production or, in fact, a one respirator at a time operation.

~;
_ .

~7 ~ 5 S~)~
In Fig. 5, a schematic of layered materials illustrates, in cross-section, the initial orien~ation of materials used to produce webs 14 and 16 of respirators according to the invention.
S In the illustrated orientation of materials 18, 20 and 22 used to produce each of webs 14 and 16, the webs are separated at scrim sides with a dielectric buf~er 38 (Fig. 6) and all three pieces are brought together for subsequent heat-sealing operations, e.g. by dielectric heating in conventional fashion ~ and not requiring detailed discussion herein. Those - interested in such details, however, may refer to literature on the subject of which Electronics for Industry by ~.I. Be~dz is exemplaryD John Wiley ~ Sons, Inc is the Publisher~
- If sealing with heated dies or the like is selected, buffer 38 would accordingly comprise a : suitable heat insulating material.
A preferred next operation is to heat seal portions of top and bottom webs 14 and 16 along lines 4U
each having the configuration of one of edges 2~
and 30 of a respirator 10 to be producedO ~ig. 7 illustrates three such lines 40 from which three respirator bodies 12 will ultimately be completed.
It should be understood, however, that similar heat-sealed lines 40a will be produced on web 16 which is not visible in Fig. 7. In Fig. 8, hea~
seals 40 and 40a are illustrated diagramma~ically as single lines each.
Buffer 38 is next removed or the strip 42 of web materials is advanced therebeyond as at Fig.
whereb~ heat sealing along lines 44, i.e. completely through both webs 14 and 16 completes the respirator ou~line in each case leaving heat seals 40 and 40a .~
~ . .

- se~arable. Fig. 10 ill~strates the seal alon~ lines 44.
Respirator bodies 12 are finally cut from supply strip 42 by trimming through webs 14 and 16 alongr but outwardly of seals 40, 40a and 4~
Headbands 32, 34 (Figs. 1, 3 and 4) are then attached, e.g. with cement, rivits, staples or by heat sealing.
Ribs 24, ~6 may be formed by heat sealing in a proper position on supply strip 42 at the time of forming seals 40, 40a (Figs. 7 and 8), e.g~ as shown with single lines 24a, or subsequent to cutting and removal of respirator bodies 12. In ~he latter case, a suitable buf~er may be slipped in~o each respirator body 12 to prevent the ribbing from connecting the two webs 14 and 16 together.
l'; Lastly, i~ not at an earlier s~age of the : process, chevron 36 (Fig. 1, 3 an~ 4) in flat form is cemented in placeO
t---- , Alternative fabricative procedures may include reversing the order of effecting seals 4n 7 40a and 44, - 20 precutting webs 14 and 16, i.e. before sealing the edges; using heated dies and pressure to form seals 40, 40a and 44 and/or seaLing ultrasonically.
Those skilled in the art will readily appreciate that there are various other modifications and adaptations - 25 of the precise forms of the invention here shown which may sui~ particular requirements. Accordingly, the foregoing illustrations are no~ to be interpreted as restrictive of the invention beyond that necessitated by the following claims.
.

Claims (16)

1. A folded respirator comprising:
a pair of superimposed multiply layered webs of air-permeable materials, at least one of which is characterized by an adaptability to filtering undesirable airborne contaminants with a passage of air therethrough;
said webs each having one edge of special curvilinear outline for face-fitting purposes when said respirator is brought to use;
the materials of said webs being all edge joined together about all but said one curvilinear edge of each and similarly separately joined together along said curvilinear edges whereby selective separation of said separatedly joined curvilinear edges opens said respirator for wearing; and means for holding said opened respirator against against a wearer's face.
2. A respirator according to claim 1 wherein said one layer of each of said webs comprises a lofty fiber media.
3. A respirator according to claim 1 wherein said one layer of each of said webs is interposed between scrim and shell layers.
4. A respirator according to claim 3 wherein each shell layer is disposed outwardly of said respirator for protection of said one air-filtering layer and each scrim layer is disposed inwardly of said respirator.
5. A respirator according to claim 1 wherein said edges of said materials of said webs are heat sealed together.
6. A respirator according to claim 5 wherein additional lines of heat sealing of said materials of said webs are included for reinforcement of said webs, said lines extending approximately perpendicularly to the general direction of each of said curvilinear edges of said webs.
7. A respirator according to claim 1 wherein said respirator further comprises at least one headband having its opposite ends attached to at least one of said webs.
8. A respirator according to claim 1 including malleable means affixed to a side of one of said webs for use in fitting said respirator to a face.
9. A respirator according to claim 8 wherein said malleable means is in the configuration of a chevron.
10. The method of making a folded respirator comprising the steps of:
superimposing first and second webs of multilayered respirator facepiece material;
performing one of the following steps in an order preceding the other;
(a) separately joining layers of each web together along a line configured to provide a face-engaging edge of said respirator;
(b) joining all layers of said first and second webs together along at least one line extending away from an intended position of one of corresponding ends of said lines of face engaging edges of said respirator to the opposite of corresponding ends of said face-engaging edges;
trimming said webs around and outwardly of all of said lines of joining of said materials; and attaching head supporting means to at least one of said trimmed webs.
11. The method according to claim 10 wherein said joining of said of layers of materials is effected by heat sealing operation.
12. The method according to claim 11 wherein said webs are trimmed to desired shape prior to said joining of said layers of materials.
13. The method according to claim 11 wherein said separate joining of said web layers along lines configured for face engaging purposes is performed with a single heat sealing operation utilizing a heat sealing buffer between said webs to prevent joining of said face-engaging edges.
14. The method according to claim 13 wherein said joining of all layers of said first and second webs is accomplished with a single heat sealing operation without employment of said buffer.
15. The method according to claim 10 including the steps of attaching at least one headband to said trimmed webs.
16. The method according to claim 15 further including attachment of a malleable chevron approximately centrally upon one side of one of said trimmed webs adjacent to said face engaging edge thereof.
CA 406442 1981-08-12 1982-06-30 Disposable respirator Expired CA1185500A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US29231281 true 1981-08-12 1981-08-12
US292,312 1981-08-12

Publications (1)

Publication Number Publication Date
CA1185500A true CA1185500A (en) 1985-04-16

Family

ID=23124127

Family Applications (1)

Application Number Title Priority Date Filing Date
CA 406442 Expired CA1185500A (en) 1981-08-12 1982-06-30 Disposable respirator

Country Status (5)

Country Link
JP (1) JPS5827567A (en)
CA (1) CA1185500A (en)
DE (1) DE3230071A1 (en)
FR (1) FR2511253B1 (en)
GB (1) GB2103491B (en)

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US6383514B1 (en) 1996-11-28 2002-05-07 Henkel Kommanditgesellschaft Auf Aktien Use of mixtures of active substances for the production of hypocholesterolemic agents
US6623746B1 (en) 1998-07-16 2003-09-23 Cognis Deutschland Gmbh & Co. Kg PIT emulsions, methods of softening paper using the same, and paper substrates treated therewith

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USD776257S1 (en) 2005-06-27 2017-01-10 3M Innovative Properties Company Personal respiratory protection device
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US9770058B2 (en) 2006-07-17 2017-09-26 3M Innovative Properties Company Flat-fold respirator with monocomponent filtration/stiffening monolayer
US8029723B2 (en) 2006-07-31 2011-10-04 3M Innovative Properties Company Method for making shaped filtration articles
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US20080099022A1 (en) 2006-10-26 2008-05-01 3M Innovative Properties Company Respirator That Uses A Predefined Nose Foam Shape
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KR20100098502A (en) 2007-10-09 2010-09-07 쓰리엠 이노베이티브 프로퍼티즈 컴파니 Filtering face-piece respirator having nose clip molded into the mask body
US8430100B2 (en) 2008-02-25 2013-04-30 Prestige Ameritech Ltd. Universal fit face mask
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6383514B1 (en) 1996-11-28 2002-05-07 Henkel Kommanditgesellschaft Auf Aktien Use of mixtures of active substances for the production of hypocholesterolemic agents
US6623746B1 (en) 1998-07-16 2003-09-23 Cognis Deutschland Gmbh & Co. Kg PIT emulsions, methods of softening paper using the same, and paper substrates treated therewith

Also Published As

Publication number Publication date Type
FR2511253A1 (en) 1983-02-18 application
DE3230071A1 (en) 1983-03-03 application
FR2511253B1 (en) 1985-11-22 grant
CA1185500A1 (en) grant
JPS5827567A (en) 1983-02-18 application
GB2103491B (en) 1985-01-30 grant
GB2103491A (en) 1983-02-23 application

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