US2228218A - Respirator - Google Patents

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Publication number
US2228218A
US2228218A US112646A US11264636A US2228218A US 2228218 A US2228218 A US 2228218A US 112646 A US112646 A US 112646A US 11264636 A US11264636 A US 11264636A US 2228218 A US2228218 A US 2228218A
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Prior art keywords
wall
filter
material
face piece
respirator
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Expired - Lifetime
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US112646A
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Schwartz Nathan
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Hygeia Filtering Corp
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Priority to US112646A priority Critical patent/US2228218A/en
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    • AHUMAN NECESSITIES
    • A41WEARING APPAREL
    • A41DOUTERWEAR; PROTECTIVE GARMENTS; ACCESSORIES
    • A41D13/00Professional, industrial or sporting protective garments, e.g. surgeons' gowns or garments protecting against blows or punches
    • A41D13/05Professional, industrial or sporting protective garments, e.g. surgeons' gowns or garments protecting against blows or punches protecting only a particular body part
    • A41D13/11Protective face masks, e.g. for surgical use, or for use in foul atmospheres
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S55/00Gas separation
    • Y10S55/35Respirators and register filters

Description

Jan. 7, 1941.

N. SCHWARTZ RESPIRATOR Filed Nov. 25, 1956 i Z 2 2 Mm ilililiis i.:

Patented' Jan. 7, ,19,41

PATENT oFFlcE RESPIRATOR Nathan Schwartz, New York, N. Y., assigner to Hygeia Filtering Corporation, New York, N. Y.

Application November 25, 1936, Serial N o. 112,646

9 Claims.

This invention relates rto filter type respirators adapted to cover the nose and mouth of the wearer for the purpose of protection against dust fumes and injurious gases and is a modification of my application for Letters Patent No. 2,112,213, filing date December 3, 1935, and my copending application Serial No. 110,557, ling date Nov. 13, 1936, and my Letters Patents 2,035,097 and 2,055,853. ,e i

.The invention broadly aims to provide a respirator of minimum size and weight while anording a maximum area of filtration and also to minimize the reinhalation of exhaled air and also to facilil tate the replacement of filter material and also to provide a comfortable and air tight face piece.

More particularly the invention resides in a molded cup shaped semiflexible elastic rubber face piece or its ,equivalent which has a mar- 20 ginal ange forengaging the face of the wearer and a filter unit is provided which has a substantially rigid base and the said filter unit is connected with the face piece by means of registering foramina and eyelet Joints. The head band 5 is secured to the rear side of the substantially rigid wall of the filter unit and is fastened at the back of the neck and thereby compression occurs at the face engaging part which causes anairtight flt.

Another feature is to permit Athe use of several grades of nlter material. That'is, soft, stiff and semi-stiff lter fabrics are made practical for fitting at the marginal portion of the wall of the filter imit. Recent high standards of require- 35 ment in efiiciency of filtration demands suitable and convenient methods of emplacement 'of the improved filter fabrics which have been and are being introduced for respirator use. e Further explanations will be made later on in the specifi- 40 cation..

Another object is to reduce the weight of the respirator by providing spacing means for the lter material by attaching fabric pieces at the inner side of the filter fabric instead of attach- 5 ing rib elevations at the anterior side of the wall of the casing. This method is particularly adaptable and practical with the recently improved filter fabric material which is at present giving a high standard of efllciency. Namely the im- 50 proved lter fabric is stiilened in the processing of its texture for the purpose of obtaining an increased iiltering efficiency. Therefore due to the said stiil'ened texture of the filter fabric. small pieces of fabric material are attached to the' sa inner side of the said filter fabric. Another ad- .ing the positions of the molded elastic cup shaped (Cl. 12S-146) vantage that is obtained by this improved spacing method is cleanliness. It is apparent that the possible collections of dust or other extraneous undesirable matter about the spacing extrusions are definitely avoided.

With the above recited and other objects in view, reference is had to the following description and accompanying drawing in which there is exhibited an example or embodiment of the invention while the claims define the actual scope of the same.

In the drawing:

Figure 1 is a perspective view of the improved respirator in applied position.

Figure 2 is a top view of the respirator illustrating the relations of the face piece, lter unit and head band, and a broken side section shows the arrangement of cheek flange.

Figure 3 is a rear view of the respirator, showface piece and the fllter unit.

Figure 4 is a section of 4 4 of Figure 3.

Figure 5 is anenlarged detailed view of the marginal section of the lter unit, illustrating the collar fastener.

Figure 6 is a perspective view of the collar fastening device.

Figure 7 is a modified form of the lter unit and illustrates a stiffened filter fabric having no so bend at the marginal section and having teats at its inner side.

Figure 8 is a section at 8-8 of Figure 7 and illustrates the attachment of the spacing teat.

Figure 9 illustrates the stitches for attaching 35 the spacing teats to the filter fabric. V

Figure 10 is a section on line lil-I0 of Figure 4.

Referring to the drawing by characters of reference, A designates the face piece of the respio rator, B designates the filter unit, CI the valvel and D the head band.

The face piece A, of the respirator is constructed 'of molded elastic semi-flexible and resilient rubber or its equivalent and is substantially 5 cup shaped to fit at the nose, chin and cheeks of the wearer. The marginal engaging section of the said face piece has an inwardly directed flange I0 which flange I0 compressingly engages the face of the wearer. The said ange I0 is 5a thickened at the sides l I for engaging the cheeks and an extra amount of thickening is required at the side of the face piece 30. The reason for the altered requirement is that' the musculatures which are present at the cheek portion require a t,

Y The first form is illustrated in Figure 4. The casing I6 is substantially rigid and is connected with the rubber face piece preferably` laterally by means of registering holes I2 and eyelets I3. The casing I6 has corrugated strips of metal I'I disposed at its inner side for the purpose ofl providing an air space between the said casing wall I8 and the filter material I9. The marginal fiange `20 of the casing is directed outward and is inclined at an acute angle with reference to the wall I8. The collar fastener 2I is L sectioned and con- `forms to the shape of the marginal iiange 20 and when in applied position fits snugly and embraces the filter material I9. The said collar has an outer arm 23 for clamping the flange 20 and has an inturned arm 24 for impinging on the filter material I9. The arm 23 of the collar fastener is straight and therefore readily engages the "iiange 20 of the casing I6, but as the said arm 23 slips over the flange 20 a wedging process occurs and a vtight fit results. The arm 23 is' slightly longer than the flange 20 and therefore when it is required to remove the collar 2I for certain reasons, such as, when replacement of filter material is necessary, the said length aids in the disconnecting process. Namely, due to the said extra length of the arm 23 there is an extension 25 of the said collar. The said extension is rearward of the casing wall I8, and if disconnecting is required, the said extension 25 is tapped against a solid material and readilyvloosens, or a solid material is tapped against the said extension with the same easy disconnecting result.

In the first form of this invention the casing I6 of the filter unit is substantially rigid and is preferably made of aluminum or its equivalent and the said casing has attached at the inner side of the wall IB corrugated strips I1 for the purpose of providing an airspace 21 between the wall I8 and the filter material 22. Also in this form the filter material fabric is preferably of soft texture and its edge extends slightly beyond the marginal end oft-the flange 20 of the casing I6, and the said filter material reaches the outer arm 23 of the collar fastener 2I and as the said collar fastener 2| is slipped over the flange 20, the said edge of the filter material is flexed arid impinged over the flange 20, as shown in Figure 4. In Figure 5 the said filter material is shown prior to its complete iiexion.

In the second form of this invention the casing I6 is the same as in the first form. 'I'he difference is that it is adapted for stiff filter fabric material 22a and-therefore a Variation in its adaptation is provided. Namely the size of the filter material 22a, is to approximate the size of the flange 20 and therefore there is no flexion of its edge such as there is in 'the first form. Due to the thickness and also the stiffness of the filter material 22a it would be impractical to cause any flexion at the connecting margin In Figure 7 the said connectingmargin is illustrated. Other- "wise the collar arrangement for fastening and. securing the filter material 22a is the same as.

was in the first form. Also in the second form drawing the said stitches are designated by the l numeral 28.'

In Figures 3 and 4 the iiange arrangement at the face piece is clearly illustrated. It is to be` noted that at the chin and also at the nose sections the flanges are comparatively thin and that they are disposed atan acute angle with its base of attachment, namely the body of the face piece. It is also to be noticed that at the sides, namely at the cheek sections of the face piece and also at the side iianges II there is a thickening of the material and the flanges are disposed at right angles with relation to the face piece. When the side fianges II 'engage the face of the wearer, the said flanges are at right angles to the face.

It is to be noted that the head band is attached to the posterior side of the wall I8 of the casing I6 and the saidwall is also connected by means of registering holes I2 to the face piece A.

vTherefore when the head band is fastened to the back of theneck of the wearer and the face piece A is thereby drawn backward, the nose and chin flanges become actively engaged in tightening against the nose and chin and the ac ute angle formations of the flanges become more acute and the angle may become obliterated if the compression is great enough. Also note that the right angle formation of the ange II at the cheek portion is also pressed in a forward direction, because the face piece is drawn rearward and therefore an acute angle is formed at the side flanges both in relation to the face piece and the face of the wearer. 'I'liis arrangement is of special value because the cheek is muscular and must contact a substantial thick right angle flange, while the nose and chin parts are sensitive and should contact with a non-irritating material, which is arranged in a definite manner whereby there is a definite yield at the time of compression. The said yield therefore provides a comfortable and at the same time an effective nose and chin engagement with the said flanges I 0. As stated the cheek portion of the face is not as sensitive to pressure as the chin and nose parts and therefore the right angle fiange at the cheek part is thick for the reason that only little yield or none is necessary. However what is obtained is a slight yield and a slight inclination oi the flange I I to form an acute angle. It may be stated that the part 30 of the face piece A in the region of the cheek engaging part also needs to be substantially thick so that it does not yield readily to pressure.

As a further means of safeguard for preventing any dislocations at the flange-engaging sections of the face piece A an additional strip of material 26 is added in a spanning position transversely and preferably at the outer side of the face piece A. The said strip 26 is preferably integral with the face piece A, but may be adhesively attached thereto, that is a semi-exible strip of rubber may be placed insuch a transverse spanning position.

What is claimed is:

1. In a respirator, a body portion having an inlet port, a filter unit `having a wall with an anterior convexity and an eccentric aperture, and a filter pad having elevations, the said pad being mounted in confronting relation to the said wall over the said aperture and is spaced from the said wall by the said elevations, and the conguration of the said pad is similar to the said wall, and the said aperture and inlet port register with one another in a manner whereby the said unit is adjacent to the said body portion.

2. A respirator having a body portion with an inlet port, a filter unit having a wall with an eccentric aperture, filter Vmaterial and means for securing the said material at the marginal portion of the said wall comprising a forwardly dil rected flange located at the margin of the said wall and a substantially L-sectioned displaceable rim fastener overlapping the said ange and embracing upon the edges of the said material whereby the said material is secured thereat, and one of the arms of the said L extends rearward beyond the said wall whereby the rear end one wall with an anterior convexity and lter material of a similar conguration, and the said wall has an outwardly directed marginal flange and the lter material is removably secured at the said marginal flange by means of a displaceable collar fastener consisting of an L-sectioned rim which rim embraces the filter material at the outer portion of the said fiange, when the said rim is in applied position, the rear edgeof the said rim extending beyond the said wall which makes it possible to easily remove the said rim fastener by tapping upon the said rear edge.

4. In a respirator, a body portion having an inlet port, a filter unit having a wall with an eccentric aperture, filter material and means for securing the said material at the marginal portion of the said wall comprising a substantially L-sectioned marginal rim embracing upon the edges of the said material and thereby securing the said edges to the marginal portion of the said wall and the said wall has an anterior convexity and the said material is of a similar configuration, and the said material confronts the said wall and the said material has porous corrugations which corrugations provide means to space the material from the wall and also prvide a larger inner surface filter area whereby breathing is made easier, and the said aperture connects with the said inlet port, whereby communication is established between the said unit and the said body portion.

4. In a respirator, a face piece having an inlet (port, a filter unit havinga wall with an aperarea is provided for the pad. making easier breathing for the wearer, and the said port and aperture register with one another in a manner whereby the said unit is adjacent tothe said face piece. 6

6. In a respirator, a face piece having an inlet port, a nlter unit having a wall with an aperture, a filter pad having elevations, and means provided to removably secure the said pad at its edges to the marginal portion of the said l wall, in a manner -whereby the said corruga-` tions confront the said wall and provide a spacing for the pad, and the' said elevationsfare oi.'` filter material substance whereby a large filter surface area is provided and resistance to breathing is thereby diminished, and the said port and aperture register with one another in a manner whereby the said unit is adjacent the said face piece.

7. In a respirator, a face piece connected with a filter unit having a wall, filter pad with spacing teats, and the said teats are of porous material and attached to the said pad at its inner surface, and means provided whereby the saidpad is mounted in confronting relation to the 2Q said wall in a manner whereby the edges of the pad are removably secured to the marginal portion of the wall and the said tents cause the said pad to be spaced from the said wall, thereby creating a large internal surface lter area $0 whereby breathing is made comparatively easy.

8. A respirator having a body portion connected with a filter unit having filter material.A an independent L-sectioned marginal clamping means, and a wall with a marginal seat, the said material being removably secured at its edges at the said seat in a manner whereby the said clamping means embraces the edges of the said material with one arm of the L .while the other arm extends beyond the said wall whereby the said extending arm may be tapped upon for the purpose of disengaging the clamping means and removing the filter material.

I9. In a respirator a face piece having a set back portion below the nose line wherein is lo-4 cated an exhaust valve and having an inlet port, a filter holder having a wall with an aperture and a marginal seat, filter pad having elevations. and marginal clamping means, the said pad being mounted in parallel relation to the said wall by having.- its edges removably secured at the said marginal seat in a manner whereby the said clamping means embraces the said edges and thereby clamps the same against the said seat, and the said elevations are arranged to confront the said wall and thereby space the pad therefrom, and the said aperture registers with the said inlet port in a manner whereby the filter holder is located adjacent the said face'- piece. B0

NATHAN SCHWARTZ.

CERTIFICATE OF CORRECTION. Patent No. 2,228,2LS. January 7,' 1911.1.` Y NATHAN SCHWARTZ. l It is hereby certified that error appears in the printed specification of the 4above numbered patent requiring correction as follows; Page 5, seoond colmn, line IIL-l2, claim 6, for the word "corrugations" read eleva--A tionsand that the said Letters Patent should be read with -this correction therein that the same may conform to the record of the case in the Patent Office.

Signed andsealed this 29th day of April, A. D. 1914.1.

l Henry Van Ardale, (Seal) Acting Commissioner of Patents.

US112646A 1936-11-25 1936-11-25 Respirator Expired - Lifetime US2228218A (en)

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Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2433088A (en) * 1943-07-22 1947-12-23 Arthur H Bulbulian Mask structure
US5941244A (en) * 1997-07-29 1999-08-24 Mitsumasa Chino Dustproof mask
US20050199238A1 (en) * 2004-03-12 2005-09-15 Shuei-Wun Ciou Mask with grooved baffle
US20110277769A1 (en) * 2010-05-12 2011-11-17 Mei-Sheng Teng Three Dimensional Face Mask
US20120325221A1 (en) * 2011-06-24 2012-12-27 Thong Quoc Tran Lightweight Respirator
US9295799B2 (en) 2004-04-02 2016-03-29 Fisher & Paykel Healthcare Limited Breathing assistance apparatus
US9517317B2 (en) 2006-07-14 2016-12-13 Fisher & Paykel Healthcare Limited Breathing assistance apparatus
US9539405B2 (en) 2004-02-23 2017-01-10 Fisher & Paykel Healthcare Limited Breathing assistance apparatus
US9539404B2 (en) 2003-12-08 2017-01-10 Fisher & Paykel Healthcare Limited Breathing assistance apparatus
US9561338B2 (en) 2010-10-08 2017-02-07 Fisher & Paykel Healthcare Limited Breathing assistance apparatus
US9561339B2 (en) 2009-11-18 2017-02-07 Fisher & Paykel Healthcare Limited Nasal interface
US9884160B2 (en) 2004-04-02 2018-02-06 Fisher & Paykel Healthcare Limited Breathing assistance apparatus
US9901700B2 (en) 2008-10-10 2018-02-27 Fisher & Paykel Healthcare Limited Nasal pillows for a patient interface
US9907923B2 (en) 2012-09-04 2018-03-06 Fisher & Paykel Healthcare Limited Valsalva mask
USD823455S1 (en) 2017-02-23 2018-07-17 Fisher & Paykel Healthcare Limited Cushion assembly for breathing mask assembly
USD823454S1 (en) 2017-02-23 2018-07-17 Fisher & Paykel Healthcare Limited Cushion assembly for breathing mask assembly
USD824020S1 (en) 2017-02-23 2018-07-24 Fisher & Paykel Healthcare Limited Cushion assembly for breathing mask assembly
US10258757B2 (en) 2008-05-12 2019-04-16 Fisher & Paykel Healthcare Limited Patient interface and aspects thereof
US10265488B2 (en) 2000-02-25 2019-04-23 Resmed R&D Germany Gmbh Breathing mask and a sealing lip device for a breathing mask
US10328226B2 (en) 2008-05-12 2019-06-25 Fisher & Paykel Healthcare Limited Patient interface and aspects thereof
US10413693B2 (en) 2011-07-01 2019-09-17 Fisher & Paykel Healthcare Limited Nasal mask interface assembly
US10441738B2 (en) 2010-09-30 2019-10-15 ResMed Pty Ltd Mask system

Cited By (37)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2433088A (en) * 1943-07-22 1947-12-23 Arthur H Bulbulian Mask structure
US5941244A (en) * 1997-07-29 1999-08-24 Mitsumasa Chino Dustproof mask
US10265488B2 (en) 2000-02-25 2019-04-23 Resmed R&D Germany Gmbh Breathing mask and a sealing lip device for a breathing mask
US9539404B2 (en) 2003-12-08 2017-01-10 Fisher & Paykel Healthcare Limited Breathing assistance apparatus
US9539405B2 (en) 2004-02-23 2017-01-10 Fisher & Paykel Healthcare Limited Breathing assistance apparatus
US10252015B2 (en) 2004-02-23 2019-04-09 Fisher & Paykel Healthcare Limited Breathing assistance apparatus
US9974914B2 (en) 2004-02-23 2018-05-22 Fisher & Paykel Healthcare Limited Breathing assistance apparatus
US9550038B2 (en) 2004-02-23 2017-01-24 Fisher & Paykel Healthcare Limited Breathing assistance apparatus
US20050199238A1 (en) * 2004-03-12 2005-09-15 Shuei-Wun Ciou Mask with grooved baffle
US9884160B2 (en) 2004-04-02 2018-02-06 Fisher & Paykel Healthcare Limited Breathing assistance apparatus
US9295799B2 (en) 2004-04-02 2016-03-29 Fisher & Paykel Healthcare Limited Breathing assistance apparatus
US10463825B2 (en) 2004-04-02 2019-11-05 Fisher & Paykel Healthcare Limited Breathing assistance apparatus
US9517317B2 (en) 2006-07-14 2016-12-13 Fisher & Paykel Healthcare Limited Breathing assistance apparatus
US10413694B2 (en) 2008-05-12 2019-09-17 Fisher & Paykel Healthcare Limited Patient interface and aspects thereof
US10258757B2 (en) 2008-05-12 2019-04-16 Fisher & Paykel Healthcare Limited Patient interface and aspects thereof
US10363387B2 (en) 2008-05-12 2019-07-30 Fisher & Paykel Healthcare Limited Patient interface and aspects thereof
US10328226B2 (en) 2008-05-12 2019-06-25 Fisher & Paykel Healthcare Limited Patient interface and aspects thereof
US9901700B2 (en) 2008-10-10 2018-02-27 Fisher & Paykel Healthcare Limited Nasal pillows for a patient interface
US9907925B2 (en) 2008-10-10 2018-03-06 Fisher & Paykel Healthcare Limited Nasal pillows for a patient interface
US9561339B2 (en) 2009-11-18 2017-02-07 Fisher & Paykel Healthcare Limited Nasal interface
US10384029B2 (en) 2009-11-18 2019-08-20 Fisher & Paykel Healthcare Limited Nasal interface
US20110277769A1 (en) * 2010-05-12 2011-11-17 Mei-Sheng Teng Three Dimensional Face Mask
US8176918B2 (en) * 2010-05-12 2012-05-15 Mei-Sheng Teng Three dimensional face mask
US10456545B2 (en) 2010-09-30 2019-10-29 ResMed Pty Ltd Patient interface systems
US10449317B2 (en) 2010-09-30 2019-10-22 ResMed Pty Ltd Patient interface systems
US10441738B2 (en) 2010-09-30 2019-10-15 ResMed Pty Ltd Mask system
US9561338B2 (en) 2010-10-08 2017-02-07 Fisher & Paykel Healthcare Limited Breathing assistance apparatus
US10272218B2 (en) 2010-10-08 2019-04-30 Fisher & Paykel Healthcare Limited Breathing assistance apparatus
US20120325221A1 (en) * 2011-06-24 2012-12-27 Thong Quoc Tran Lightweight Respirator
US10413693B2 (en) 2011-07-01 2019-09-17 Fisher & Paykel Healthcare Limited Nasal mask interface assembly
US9950130B2 (en) 2012-09-04 2018-04-24 Fisher & Paykel Healthcare Limited Valsalva mask
US9907923B2 (en) 2012-09-04 2018-03-06 Fisher & Paykel Healthcare Limited Valsalva mask
US9907922B2 (en) 2012-09-04 2018-03-06 Fisher & Paykel Healthcare Limited Valsalva mask
USD823455S1 (en) 2017-02-23 2018-07-17 Fisher & Paykel Healthcare Limited Cushion assembly for breathing mask assembly
USD823454S1 (en) 2017-02-23 2018-07-17 Fisher & Paykel Healthcare Limited Cushion assembly for breathing mask assembly
USD824020S1 (en) 2017-02-23 2018-07-24 Fisher & Paykel Healthcare Limited Cushion assembly for breathing mask assembly
USD837973S1 (en) 2017-02-23 2019-01-08 Fisher & Paykel Healthcare Limited Cushion assembly for breathing mask assembly

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