US2505173A - Respirator - Google Patents

Description

T. A. CONLEY April 25, 1950 RESPIRATOR 2 Sheets-Sheet 1 Filed Dec. 24, 1948 Fig 4 INVEN TOR. THOMAS A. CONLEY ATTORN Y April 25, 1950 T. A. CONLEY RESPIRATOR 2 Sheelta-Sheec Filed Dec. 24, 1948 INVENTOR. THOMAS A. CONLEY Patented Apr. 25, 195

American Optical Claims.

This invention relates to respirators and has particular reference to improved respirators of a'type for attachment overthe nose and mouth of an individual for filtering particulate or gaseous contaminants from air to purify it for breathing. j

An object of'this invention is to provide a respirator embodying'a face piece molded of rubber or similar flexible material having the contour edgeportions 'thereof'which contact the face of the wearer turned inwardly so as to provide a comfortable snug fit against the face preventing leakage at contacting surfaces, the edge portions engagingthe'bridge of the nose and the chin being formed substantially fiat to parallel the facial features, thus providing better contact and giving more comfort to the wearer, the face piece also embodying a flexible bracket attached to the inner surface thereof, which bracket provides for easier adjustment of the face piece to the face of the wearer and retains the face piece in desired adjusted shape, such a face piece being easily and efficiently adapted to faces of varying lengths.

Another principal object of the invention is to provide improved inhalation and exhalation valve constructions, said valves being recessed to avoid interference caused by contacting the wearers face or clothing during'the process of breathing, the face piece of the'respirator embodying portions of thickened'area around the inhalation and exhalation parts permitting the valves to be recessed without the necessity of providing separate guards to protect the valves.

Another object is to provide a respirator of the above character with an improved inhalation valve construction to minimize the resistance due to'the sticking of a flexible valve member to a fiat member contacted thereby, and embodying a valve seat having a circular knife-edge rim Company, Southbridge, Mass, av voluntary association of Massachusetts Application December 24, 1948, Serial No. 67,180

adapted to be engaged by the flexible valve member'which is suspended upon a pin member supported by the valve seat, the pin member also having a portion extending toward the filter to fiat disc type,' such as impregnated'paper, felt,

or the like, or of the filled cartridge type containing such filtering media as charcoal, silica ge1,"or-the like, the means embodying a clamp vring'disp'osed overthe peripheral edgeof the filter and engaging the peripheral edge portion of the onto the holding device therefor without necessitating rotation of the cover with possible consequent damage to or unseating of the filter result ing in leakage of unfiltered air.

Another object is to provide a respirator'of the above character having; a flexible metal brace for providing easy adjustment of the face piece to the face of the wearer and retention of the face. piece in adjusted position, with the headband supporting the device on the 'Wearers face being; so connected that the pull thereof is directed to the metal brace rather than to the pliable ma terial of the face piece.

Another object of the invention, is to provide a compact and light weight respirator of the above character in which the filter elements are easily removed and replaced and in whichthe construction of parts is such that they provide unusually low resistance to breathing,

Other objects and advantages of the invention will become apparent from the following description taken in connection with the accompanying drawings, in which:

Fig. 1 is a front elevational view of a respirator embodying. the invention;

Fig. 2 is a sectional view. taken on line 2-2 of Fig. 1 and showing particularly the improved method of shaping the edge portions of' the face piece for engagementwith the face of the wearer;

Fig. 3 is a rear elevational view of the device illustrated in Fig. 1;

Fig. 4 is a fragmentarysectional view taken on line 44 of Fig. 1; and I Fig. 5 is a fragmentary front elevational view of a portion of the face piece adjacent the filter means showing the construction ofthe face piece in this area.

In the manufacture and use of respirators of the type embodying the present invention, comfort and efficiency are the most important features to be considered. Therefore, the present device is particularly constructed so that it will be com fortably supported upon the face of the wearer with the contour edges of'the face piece being shaped for increased surface engagement .with the face and with flexible reinforcin'g meansbein provided on the inner surface-of the facepiece for adjusting the face piece to-fit more com fortably on the wearersface and retaining it in adjusted position.

Respirators should also be provided with efficient inhalationand exhalation'valves constructed so. as to provide-greater ease of breathing with less possibility of inefficiency caused by clogging,

aEsT AVAILABLE COPY sticking or otherwise poorly Working parts, which condition adds to the resistance to breathing. The present invention overcomes many of these objections by providing inhalation and exhalation valves having an improved construction and which are recessed so that the operative parts of the valves will not engage surfaces or objects which may cause consequent interference with the operation thereof.

Referring more particularly to the drawings wherein like characters of reference designate like parts throughout the several views, the respirator embodying the invention comprises a face piece 6 adapted to cover the lower portions of the face of a wearer and cushioned under the wearer's chin, the face piecetbeing formed of flexible material such as soft rubber or the like which can readily adaptitself to the contour of the facial features of the wearer so as to prevent passage of air between the edges of the face piece and the wearer's face. The face piece 6 is provided with an inturned lip 1 throughout its entire contour edge, which lip 1 may be substantially decreased in thickness from the major portion of the face piece to provide greater flexibility thereof and to insure an emcient seal between the face piece and the wearer's face with maximum comfort to the wearer, and in the present construction is formed as a rounded lip about a major portion of the contour edge of the face piece, and as a fiat lip adjacent the chin and nose bridge portions thus being formed substantially parallel to these features.

In accordance with the invention, air, as it passes into the face piece '6 upon inhalation by the wearer, is filtered by a suitable filter 8 (Fig. "4) which filter may be of either the flat disc or the filled cartridge type possessing the desired filtering and air resistance characteristics. The

illustrated embodiment of the invention shows l a pair of filter elements disposed symmetrically one on each side of the face piece and in spaced opposed relationship on theouter surface thereof out of the line of vision of the wearer. In addition to being out of the useful field of vision of the wearer, this construction provides equal weight or balance to each side of the respirator, thereby decreasing strain on the face piece, which sometimes exists when the filtering element is disposed centrally of the face piece, and adding to the comfort of the wearer.

A feature of the invention resides in the provision of particularly advantageous means for supporting a filter such as a felt filter 8 while positively sealing it against leakage of air around its edge. Each of the filter units includes a cylindricalcasing comprising a circular ring-like base 9, a cover i0, and a retaining or clamping ring I I, all of which are adapted to be positioned as a unitover and externally of an opening l2 communicating with the interior of the face piece, the face piece being formed substantially thick adjacent the openings l2. The opening l2 (Fig. .5) is provided with a fiat circular edge portion l3 therearound, which portion has a pair of diametrically opposed recesses l4 formed in the edge thereof in which are adapted to reside a pair of flange extensions l5 (Fig. 4) formed on the inner edge of the base 9 and in diametrical opposition to each other. The base 9 is held firmly over the opening I2 by a grommet Hi, the outer edge portion of the grommet I6 extending over the inner edge portion it of the base ,9 holding the base firmly against the portion i3, with the exwe or) tensions i5 within the recesses l4 serving to pre vent the base from rotating.

The base 9 is formed with a forwardly extending portion 19 having a portion 20 extending outvcardly therefrom (Fig. 4) against which is adapted to reside a washer or gasket 2| of rubber, fibre or other resilient material, the portion 20 in turn having a forwardly extending portion 22 extending therefrom, the portion 22 being provided with threads on its outer surface. The disc-like filter 8 is positioned with its peripheral rear edge portion engaging the gasket 21, and the cover I0 is placed over the filter to retain it in place. The cover In is provided with a perforated front surface 23 and a side surface 24, the side surface 24 being provided with a plurality of knobs or raised areas 25 adjacent the front surface 23 and with an outwardly extending flanged portion 26 adjacent its rear edge, the flanged portion 26 engaging the filter 8. The retaining ring H is provided to retain the cover I0 and base 9 in assembled relation and is formed substantially U-shape in section (Fig. 4) with its inner portion 21 being of a size to normally reside between the knobs 25 and flange 26 of the cover it. The opposed outer portion 28 of the ring II adapted to extend rearwardly over the portion 22 of the base 9 and is provided with threads on its inner surface for engaging the threads on the portion 22. When the ring II is threaded onto the base 9, which rotary movement can be accomplished easily due to the raised areas 29 formed thereon, the edge of the ring portion 21 is brought to bear upon the flange 26 of the cover ill, pressing the flange against the filter 8. Thus, the complete unit is sealed against leakage and unfiltered air permitted to enter the assembly only through the openings 30 provided therefor in the perforated front surface 23 of the cover It].

This means enables the cover to be readily removed for easily changing filters when desired, the flange 26 provides a bearing surface for the edge of the ring portion 21 during the rotation thereof and enables the assembling of the filter unit without cutting, fraying or otherwise damaging the filter or unseating the edge of the filter from its position against the gasket which might occur as by turning a sharp or narrow edge surface in direct engagement with the fibrous surface of a filter.

To prevent collapse of the face piece 6 and to permit adjustment of the face piece to fit the facial contours of the wearer there is provided a flexible metal reinforcing member 3| (Fig. 3) positioned inside the face pieces 6, the member 3| having circular ring-like end portions 32 connected by a strap-portion 33, the end portions 32 being positioned over the inhalation openings l2 and held in place by the inner ends of the grommets IS. The face piece 5 and reinforcing member 3|, both being flexible, are easily bent and shaped so that the face piece can be adjusted to fit the wearers face and will, through the inherent characteristic of the member 3|, retain their adjusted positions.

A circular valve seat is adapted to be carried by each grommet it, each valve seat being press fit into the inner chamber of the grommet and shaped as a circular ring-like member having a perforated disc-shaped inner surface 34 directed toward the wearer's face and having an outwardly extending peripheral flange 35 formed on its rear edge in engagement with the rear end of the grommet for limiting the forward movement BEST AVAILABLE COPY of the;-seat;36.-. during assembly and thus posi-. tionin'g' the seattfi so that-the surface of a mow able valve member 31' associated therewith 1 will be positionedbelow the level of the inner surface or the=face piece '6 (Fig- 4). The valve. member 31: .is' supported by a centrally disposed pin 38' whichis carriedby the valve seat 35, the pin beingiof sufficient length toextend towardthe filter -.sufficiently to prevent the filter from sagging toward "the valve seat 36. and possibly. plugging ;the' opening I2. The valve member 3! :is- -made'=-ofthin flexible material such as gum rubbersor the like-andoperates in the convene tio nal mann'er to permit ingress of filtered air into. the=-intei ior of the face pi-e'ce through the: perforations-inane"surface .39 of the seat 3 6a'nd. to iirevenhegr'ess of exhaled airgill-toL/the filter .eleme ti "To properly sealthe unit against the pas sagetof hexhaled air, the valve member 31is adapted toseat upon a continuous substantially kni I-edge rirnfdfl formed onth'e innersurface 3fof he. valve seat iifi encircling the perforated are ,thuslpreventing sticking of the valve to the seatswhich' sometimesv occurs when moisture exists in a construction embodying a flat surface adapted-to :be'engagedby the valve. Since the face-piece is formed substantially thick adjacent the-openings! 2 the valves can be recessed suffif'ciently'jto permit efi'icient functioning thereof Without providing separate guards to protect sthej valv es fromxinterference such as be encountered-when the valve iscontacted by. the wearers face.

'; Adjacent its. lower end the face piece 6 isproyide'd;with ran'exhalation port AI-(in which is socured aebracket zhaving spaced openings 43 Jthereim A -movable exhalation valvemember 4'4 ,is'E'secu'redto the outersurface' ofthe bracket 42 bygmeans such as rivets 45 or the like andoper ates-e0- cover the openings 43 during inhalation, preventingunfiltered air from entering the face piece, and ;opens the openings to the passage of airito be exhausted therethrough. The face piece iszcon'structed so as to be of substantial thickness .adjacentthe port t! sothat the valve member 44 will;:wh'enaassernbled therein, be positionedsubstantially below the-level-of the outer. surface of .tha facepieca-thus preventingthe valve member I fromicontactin'g thewearers clothing-or other .obieets-..wit1'i possible consequent interference withfthe operation of the vaive member. v

L'TheE respiratorfis:provided with the usual head 'straps flfi for holdingit on the face of the wearer. A's-ishown in Fig. 3, the straps :46 are inserted throngh loops 4'1; The loops 4'! are adapted .to be connected'to one of a plurality of pin members :4 located ontherear of the filter base 9. Thus, ibyfoonnecting loops 47 to the desired-pin'mem- -bers-48--the straps 46 can be adjusted to provide additional comfort of the-respirator on-the face :ofithe wearer; By attaching the straps 46 to the filter-basesx9 the pull exerted by the head band 7 'will be transmitted to the metal reinforcing mem- *ben 31' rather than to the pliable material from 'wh-ichithe-face piece ismade.

- Itis tobe understood that-if desired a filter of the cartridge or canister typecan be attached to .thebase-Q in a mannersimilar to the cover 8,-as shown by dotand dashlines'in Fig. 4. The actual -,filterz-media :usedwith the present respirator, howeven'can be'greatly varied to adaptthe respirator-for use to filterieither solid or gaseous panticlesz: v

' i l inorntthe foregoing .it will 1 be seen that the invention; embodies; a,..respirator. having 6 improved means for easily and efficiently attachinga filter or filters to the face piece,.improved inhalation andexhalation valve constructions, andimproved'means for shaping the respirator face piece to the face of the wearenall of Which improved features result in .a respirator made to be'worn more. comfortably on-the',face of the wearer. 1 -Whi1e certain novel features of the invention have been shown and described and, are pointed out-in theannexed claims, it will. be apparent that various omissions, substitutions and changes in the formationand details of the device villus trated and in its. use may be by those skilled in- 'theart.without departin from the spirit of theinventionr- I Ifclaim: 1. A respiratoncomprising a flexible facepiec e shapedv substantially to fitthe face of a wearer andhaving substantially thin fiat inturned portions throughout itscontour edge for engagement with-thegvrearers face, a pair of filter carrying basesdisposed in spaced relation one on either side of the outer surface ofthe face piece each being located overa port communicating iwith the. interior of the face piece, grommets mounted withinsaidports and securing said bases to the face piece, anv exhalation-valve disposeol in the lower frontal. region of. the.face piece, and reinforcing means for the face piece comprising a flexible memberhaving end portions disposed over theinner ends of said. ports .and secured thereover by said grommets and aconnecting portion between said. end port ons. said .memloer being characterized .byjits ability to be adjusted with the face piece in" adjusting .theface piece tothe face of the wearer and to retain the face piece in adjustedposition,

2. Arespirator comprising a flexible face piece shaped substantially to fit theface of a wearer and having substantially thin fiat inturneii poiitions throughout its contour edgefor engagement with the \veai elrsface. pair oflfiltercarrying bases. disposedin spaced relation one on either side of theouter surface of the' face piece each beingiocated over aport communicating with the interior of th'e'faoe piece, grommets mounted within said ports and securing said leases to the face piece, an exhaiation valve disposed in the lower frontal regionof the face'piece, and reinforcin means for the face piece comp. a fie'xibleinember having ringrlikeend portions disposed 'over" the inner ends of said ports and secure'dthereover by said. grommets and germstantially thin narrow strap connecting said end portions, saidniember. being characterized "by its ability to be adjusted'with the face piece'in adjusting theface pi co to the face of the wearer and to retain the face 'piece'in adjusted position. A"respiratorcomprising afle ole face piece shaped substantially to fit the ace of a wearer and having substantially thin flaf. inturned portions'throughout its contour edge for engagement withthe'wearers-face'a pair of filter units disposed inspa'ce'd relation one 'oneitherside of the outer surface of the face piece, each filter unit being located over a'portcommunicating with the interior of the face piece'and comprising; a ring-like basepositioned in engagement with the outer'surfaceof the face piece-adisc likefilter positioned within said base, a foraininous cover disposed OVGI'fthB outer surface of the fiiter and having a "circular edge portion contacting the outerfperipheral edge portion of. the fi ter and a retaining rin mounted over the peripheries of saidibaseand'cover and adapted to urge said r 7 cover'toward said base to hold the filter securely in position, grommets mounted within said ports and securing said bases to the face piece, and an exhalation valve disposed in the lower frontal region of the face piece.

4. A respirator comprising a flexible face piece shaped substantially to fit the face of a wearer and having substantially thin flat inturned portions throughout its contour edge for engagement with the wearers face, a pair of filter units disposed in spaced relation one on either side of the outer surface of the face piece, each filter unit being located over a port communicating with the interior of the face piece and comprising a ring-like base positioned in engagement with the outer surface of the face piece and having at least one projection formed thereon extending towards the face piece and adapted to reside within at least one recess provided therefor in the surfaceof the face piece for preventing rotation of the base, a disc-like filter positioned within said base, a foraminous cover disposed over the outer surface of the filter and having a circular edge portion contacting the outer peripheral edge portion of the filter, and a retaining ring mounted over the peripheries of said base and cover and adapted to urge said cover toward said base to hold'the filter securely in position, grommets mounted within said ports and securing said bases to the face piece, and an exhalation valve disposed in the lower frontal region of the face piece.

5. A respirator comprising a flexible face piece shaped substantiall to fit the face of a wearer and having substantiall thin fiat inturned portions throughout its contour edge for engagement with the wearers face, a pair of filter units disposed in spaced relation one on either side of the outer surface of the face piece, each filter unit being located over a port communicating with the interior of the face piece and comprising a ring-like base positioned in engagement with the outer surface of the face piece and having a threaded portion extending in a direction away from the face piece, a, disc-like filter positioned within said base and having its inner peripheral edge portion engaging said base, a foraminous cover disposed over the outer surface of the filter and having a circular edge portion contacting the outer peripheral edge portion of the filter, and a retaining ring threadedly mounted on the threaded portion of said base and adapted to urge said cover toward said base to hold the filter securely in position, grommets mounted within said ports and securing said bases to the face piece, and an exhalation valve disposed in the lower frontal region of the face piece.

6. A respirator comprising a flexible face piece shaped substantially to fit the face of a, wearer and having substantially thin flat inturned portions throughout its contour edge for engagement with the wearers face, a pair of filter units disposed in spaced relation one on either side of the outer surface of the face piece, each filter unit being located over a port communicating with the interior of the face piece and comprising a ringlilze base positioned in engagement with the outer surface of the face piece and having a threaded portion extending in a direction away from the face piece, a ring-lil e gasket mounted within said base and in abutment therewith throughout its entire inner peripheral edge, a disc-like filter positioned within said base and having its inner peripheral edge portion engaging said gasket, a foraminous cover disposed over the outer surface .of the filter and having a circular edge portion 8 contacting the outer peripheral edge portion of the filter, and a retaining ring threadedly mount ed on the threaded portion of said base and adapted to urge said cover toward said base to hold the filter securely in position, grommets mounted within said ports and securing said bases to the face piece, and an exhalation valve disposed in the lower frontal region of the face piece.

"I. A respirator comprising a flexible face piece shaped substantially to fit the face of a wearer and having substantially thin fiat inturned portions throughout it s contour edge for engagement with the wearer's face, a pair of filter carrying bases disposed in spaced relation one on either side of the outer surface of the face piece, each being located over a port communicating with the interior of the face piece, grommets mounted within said ports and securing said bases to the face piece, a flutter valve unit disposed within each of said grommets and comprising a valve seat having a foraminous central portion and a knife-edge inwardly directed rim encircling said foraminous central portion and a flutter valve disposed over the inner surface of the valv seat in engagement with said knife-edge rim, the flutter valves being positioned. within said grommets at a sufficient depth whereby they will be unable to engage the wearers face, and an exhalation valve disposed in the lower frontal region of the face piece.

8. A respirator comprising a flexible face piece shaped substantially to fit the face of a wearer and having substantially thin fiat inturned portions throughout its contour edge for engagement with the wearers face, a pair of filter carrying bases disposed in spaced relation one on either side of the outer surface of the face piece, each being located over a port communicating with the interior of the face piece, grommets mounted within said ports and securing said bases to the face piece, a flutter valve unit disposed within each of said grommets and comprising a, valve seat having a foraminous central portion and a knife-edge inwardly directed rim encircling said foraminous central portion, a pin member centrally located in said foraminous central portion and having one end extending toward said filter and adapted to be engaged thereby to prevent the filter, when sagging, from plugging th port. and a fiutter valve disposed over the inner surface of the valve seat in engagement with said knife-edge rim, and an exhalation valve disposed in the lower frontal region of the face piece.

9. A respirator comprising a flexible face piece shaped substantially to fit the face of a wearer and having substantially thin flat inturned portions throughout its contour edge for engagement with the wearers face, a pair of filter carrying bases disposed in spaced relation one on either side of the outer surface of the face piece, each being located over a port communicating with the interior of'the face piece, grommets mounted within said ports and securing said bases to the face piece, a flutter valve unit disposed within each of said grommets and comprising a valve seat having a foraminous central portion and a knife-edge inwardly directed rim encircling said foraminous central portion, a, pin member centrally located in said foraminous central portion and having one end extending toward said filter andadapted to be engaged thereby to prevent the filter, when sagging, from plugging the port, and a flutter valve supported by the inner end of said pin member disposed over the inner surface of the valve seat in engagement with said knife-edze 9, riin, the flutter valves -being positicned within said grommets at asuflicientdept whereby. they willbe unable-to engage the wearers'iace, and an-exhalationyaivedisposed in the lower frontal region of the face piece. t I a v 10. A respirator comprising a flexible face piece shaped substantially to fit the-face of awearer and having-substantially-thin flat inturned portions throughout its contour edge for engagement with the wearers face a pair of filter" carrying bases disposed 'inspaced relation one on either side of the outer surface ofthe face piece, each being located over a port "communicating with the interior of the face piece, grommets mounted within said ports and securing said bases to the face piece, an exhalation valve unit disposed in the lower frontal region of the face piece and comprising a perforated bracket secured within an opening in the face piece and a flutter valve operatively secured to the outer surface of the bracket and covering the perforations therein, the exhalation valve unit being positioned within opening at a sufiicient depth whereby the flutter valve will be unable to engage objects positioned outside the opening, and reinforcing means for the face piece comprising a flexible member having end portions disposed over the inner ends of said ports and secured thereover by said grommets and a connecting portion between said end portions, said member being characterized by its ability to be adjusted with the face piece in ad justing the face piece to the face of the wearer and to retain the face piece in adjusted position.

11. A respirator comprising a flexible face piece shaped substantially to fit the face of a wearer and having substantially thin flat inturned portions throughout its contour edge for engagement with the wearers face, a pair of filter units disposed in spaced relation one on either side of the outer surface of the face piece, each filter unit being located over a port communicating with the interior of the face piece and comprising a ring-like base positioned in engagement with the outer surface of the face piece and having at least one projection formed thereon extending extended in a direction away from the face piece,

a ring-like gasket mounted within said base and in abutment therewith throughout its entire inner peripheral edge, a disc-like filter positioned with in said base and having its inner peripheral edge portion engaging said gasket, a foraminous cover disposed over the outer surface of the filter and having a circular edge portion contacting the outer peripheral edge portion of the filter and a retaining ring located over the peripheries of said base and cover and threadedly mounted on the threaded portion of said base and adapted to urge said cover toward said base to hold the filter securely in position, grommets mounted within said ports and securing said bases to the face piece, a flutter valve unit disposed within each of said grommets and comprising a valve seat having a foraminous central portion, an inwardly directed knife-edge rim encircling said foraminous central portion, a pin member centrally located in said foraminous central portion and hav" ing one end extending toward said filter and adapted to be engaged thereby to prevent the fiiter, when sagging, from plugging the port, and a flutter valve supported by the inner end of said pin member-and disposed over the inner surface of the valve seat in engagement withsaidwknifeedge rim, the flutter valve units being positioned within said grommets at a sufficient depth wheree by the flutter valvesiwill be unable to engagethe wearers face, an exhalation valve unit disposed in the lower frontal region of the face piece and comprising a perforated bracket secured within 'an opening in the face piece and a fluttervalve operatively secured to the outer surface of the bracket and'coverin'g' the perforations therein, the exhalation valve unit being positioned within's'aid opening at a sufficient depth whereby the flutter valve will-be unable to engage'objects positioned outside the opening, and reinforcing means for the face piece comprising a flexible member having ring-like end portions disposed over the inner ends of said ports and securely held thereover by the inner ends of said grommets and a substantially thin narrow strap connecting said end portions, said member being characterized by its ability to be adjusted with the face piece in adjusting the face piece to the face of the wearer and to retain the face piece in adjusted position.

12. A respirator comprising a face piece shaped to overlie the nose and to fit the face of the wearer, said face piece having an opening therein, a connection member secured to the face piece and having an opening therein in alignment with the opening in said face piece and an intermediate shoulder portion and an attachment portion, a filter member having its contour edges overlying the shou der portion and lying within the attachment portion, a cap-like member having a eripheral flange overlying said filter with the flan e engaging that portion of the contour of the filter overlying the shoulder portion and a connection ring member having an inwardly turned portion engaging the flange of the caplike member and having an attachment portion in connected relation with the attachment portion of the main connection means.

13. A res ator comprising a face piece shaped to overl e the nose and to fit the face of the wearer, said face piece having an opening therein, a connection. member secured to the face piece and having opening therein in alignment with the open n in said face piece and an intermediate shoulder portion and an attachment portion, a filter me her its contour edges overlying er portion lying within the attachment portion, a cap-like member having a peripheral. flange overlying said filter with the flange engaging that portion of the contour of the filter g the shoulder portion and a connection member having an inwardly turned portion engaging the flange of the cap-like member and having an attachment portion in connected relation with the attachment portion of the main I connection means, said cap-lik member having a plural ty of openings therein.

14. A respirator comprising a face piece shaped ie the nose and to engage the face of the face piece having opening there- 1 in, a connection member attached to said face BEST AVAILABLE copy 11 portion engagement with the peripheral flange of the cap and having an attachment portion in connected relation with the attachment portion of the main connection means.

' 15. A respirator comprising a face piece shaped to overlie the nose and to engage the face of the wearer, said face piece having an opening therein, a connection member attached to said face piece and having an opening in alignment with the opening in the face piece and further having an engagement portion extending in a sidewise direction and an attachment portion extending forwardly of said engagement portion, a filter member having its contour portion overlying the 10 ing ring therebetween.

THOMAS A. CONLEY.

No references cited.

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