US2206061A - Respirator - Google Patents

Respirator Download PDF

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Publication number
US2206061A
US2206061A US109526A US10952636A US2206061A US 2206061 A US2206061 A US 2206061A US 109526 A US109526 A US 109526A US 10952636 A US10952636 A US 10952636A US 2206061 A US2206061 A US 2206061A
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Prior art keywords
face
face piece
filter means
filter
filters
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US109526A
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Edward M Splaine
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American Optical Corp
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American Optical Corp
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    • AHUMAN NECESSITIES
    • A62LIFE-SAVING; FIRE-FIGHTING
    • A62BDEVICES, APPARATUS OR METHODS FOR LIFE-SAVING
    • A62B18/00Breathing masks or helmets, e.g. affording protection against chemical agents or for use at high altitudes or incorporating a pump or compressor for reducing the inhalation effort

Definitions

  • Mass setts a voluntary association of Massachu- Application November, 6, 1936, Serial No. 109,526
  • This invention relates to respirators and more particularly to' respirators fitting the face and comprising a filter for removing particles of dust or the like from the air supplied to the user.
  • An object of the present invention is to so dispose the parts of the respirator with relation to the head of the user that there is minimum interference with vision.
  • Fig. I is a perspective view of one of the various forms which the invention may assume, partly broken away to illustrate details
  • Fig. II is a sectional view on line II-II of Fig. I; I
  • Fig. III is a sectional view on the line IIIIII of Fig. I; and Fig. IV is a developed view in perspective of the assembling of the inner end of a filter with an inlet to the face piece, all but the inner end of the filter being broken away and only a fragment of the face piece proper being shown.
  • the type of respirator to which thepresent invention particularly appertains is intended to remove from the air being breathed such. particles as lodge in a porous felt material through which the air is passed.
  • a particularly troublesome problem with this type of respirator is the disposition of the filtering material so as not to interfere with the vision of the user. This problem arises out of the necessity for providing a filter or, filters having relativelyextensive super.- ficial area in order that the required volume of air may be passed and filtered Without making the user uncomfortable due to difficulty in drawing in the air through the respirator.
  • a relatively large area of filtering material is disposed in such a way as to offer but slight obstruction to the view of the-user.
  • the filtering material is made up into filtering means arranged to substantially encircle the head of the user, this filtering means being in communication with a face piece for supplying filtered air.
  • the filtering means may be arranged so as to ex tend in opposite directions along the device, such as a strip, which is placed about the head of the user to maintain the face piece of the respirator in place.
  • the face piece 5 is of such shape and contour as to fit over the nose and mouth of the user and provide air-tight contact with the face, without overlying the eye cavities. As shown,
  • the body portion of the face piece is of metal such as aluminum, and sealing engagement with the face is afforded by a rubber flange 5a mountedon the rim of the body portion.
  • exhalation valves 6 are provided on the to permit such discharge and will be reseated after such discharge so as to prevent air bein drawn in through the perforations 8.
  • the inlets I0 to the face piece may be formed.
  • each inlet I0 is so shaped as to fit theopen end of the filter l2 which suppliesl'filtered air thereto.
  • each inlet N3 is relatively narrow, tapering fromfa rounded end at the bottom towards the top so that theside walls substantially meet at .the
  • each valve l5 being. secured at its opposite ends, asindicated at IS.
  • the inhalation valves l5 function in similar manner to the exhalation valves 6, except that they admit air instead of permitting the discharge of used air.
  • a relatively dense felt is a suitable material for this purpose.
  • This felt may be formed into elongate filters l2 having substantially the cross section shown in Fig. III of the drawing.
  • a light coil spring I8 extending-along the bottom portion of each filter I 2, as'illu strated in Figs. I and III, helps to keep these filters in expanded condition, even while the user is illustrated in Fig. I, the ends of the filters l2 are connected to the strap by slides 23 which permit sufiicient relative movement between the strap and the filters to permit the strap to accommodate itself to the head in use.
  • each inlet carries a series of prongs 25, which are so directed as to hook into the material of the respec tive filters.
  • a clamp 26 is slidable along each filter so as to overlie the inlets I0, and more particularly, the prongs 25.
  • Each clamp 26 has a reversely bent edge 21, which is adapted to engage with the inturned edge 28 of a coupling 28.
  • the coupling 29 may he slid downwardly in interlocked engagement with the reversely bent edges 21, thus firmly positioning the inner ends of the two filters on the two inlets ID.
  • the coupling 29, when in position, overlies and shields the inhalation valve or valves 6.
  • a respirator embodying the present invention has the advantage of compactness without necessitating a reduction in the extent of superficial area of the filter material; the filters are quick ly detachable, so that it is not a cumbersome operation to replace them; and the arrangement of the filters in winged fashion disposes them in such a way as to interfere to a minimum extent with the vision of the user. Moreover, there is no looseness or flapping of the parts,
  • each wing of the filtering means affords the further advantage that the taper is from the bottom to the top, so that the outer side slopes away from the eye, thus giving greater freedom of vision.
  • a respirator comprising a face piece having a pair of opposed inlets, filters telescoping with said inlets, clamps slidable along said filters each to clamping position over the respective inlet, a coupling for connecting said clamps together in clamping position, and an exhalation valve shielded by said coupling.
  • horn-like filter means of filter material having filtering characteristics substantially throughout the entire area thereof, said horn-like filter means each having a relatively free closed end and an opening in the opposed end thereof with each of said ends having an opening therein being fitted about one of the respiratory openings of the face piece, means for holding said filter means on said face piece over said respiratory openings and supporting means for engaging the head and for holding the face piece on the face, said filter means each having a connection adjacent the closed end thereof with said supporting means whereby the filter means is held in relatively close relation with the face.
  • a cuplike face piece having an edge portion shaped to engage the face and having respiratory openings in the opposed side walls thereof, relatively long and slendor horn-like filter means of filter material having filtering characteristics substarntially throughout the entire area thereof, said horn-like filter means each having a relatively free closed end and an opening in the opposed end thereof with each of said ends having an opening therein being fitted about one of the respiratory openings of the face piece, means for holding said filter means on said face piece over said respiratory openings and supporting means for engaging the head and for holding the face piece on the face, said filter means each having a connection adjacent the closed end thereof with said supporting means whereby the filter means is held in relatively close relation with the face and flexible means extending lengthwise of the filter means for normally tending to retain them in extended relation with the face piece.
  • a face piece adapted to overlie the nose and mouth of the wearer and having an edge portion for engaging the face, said face piece having a respiratory opening therein, relatively long and narrow filter means having an open end overlying said respiratory opening and having its opposite end closed, said filter means being formed of relatively flexible filtering material having a filtering function substantially throughout the entire area thereof, connection means for holding said filter means on said face piece over said respiratory opening and band-like means encircling the head for holding said face piece on the face, said filter means having a connection with the band-like means adjacent the closed end thereof for holding the filter means in relatively close relation with the face.
  • a face piece adapted to overlie the nose and mouth of the wearer and having an edge portion for engaging the face, said face piece having a respiratory opening therein, relatively long and narrow filter means having an open end overlying said respiratory opening and having its opposite end closed, said filter means being formed of relatively flexible filtering material having a filtering function substantially throughout the entire area thereof, connection means for holding said filter means on said face piece over said respiratory opening and band-like means encircling the head for holding said face piece on the face, said filter means having a connection with the band-like means adjacent the closed end thereof for holding the filter means in relatively close relation with the face, and resilient supporting means secured to the face piece adjacent the respiratory opening and extending longitudinally of the filter means for normally holding it in extended relation with the face piece.
  • a face porting means encircling the head of the wearer piece adapted to overlie the nose and mouth of the wearer and having an edge portion for engaging the face, said face piece having a respiratory opening therein, relatively long and nar row horn-like filter means having an open end overlying the respiratory opening and having its opposite end closed, said filter means being formed of filtering material having a filtering function substantially throughout the entire area thereof, and supporting means for holding said filter means in relatively close relation with the face with the said filter means having a relatively flat surface for engaging the side .of the face and being extended substantially along the line of said supporting means with a connection adjacent the closed end thereof with said supporting means.
  • a face piece shaped to fit about the nose and mouth of the wearer and having an edge portion for engaging the face, said face piece having respiratory openings therein, horn-like filter means each having an open end portion fitting about one of said respiratory openings and each having its opposite end closed, said filter means having a filtering function substantially throughout the entire area thereof, common connection means for holding said filter means on said face piece over said respiratory openings and band-like supfor securing the facepiece to the face, said filter means extending substantially along the line of said band-like means and each having a con- .nection with said band-like means adjacent the closed ends thereof.
  • a face piece shaped to fit about the nose and mouth of the wearer and having an edge portion for engaging the face, said face piece having respiratory openings therein, horn-like filter means each having an open end portion fitting about one closed ends thereof and resilient means extending longitudinally of said filter means for normally holding said filter means in extended relation with said face piece.

Description

E. M. SPLAINE July 2, 1940.
RESPIRA'IOR Filed Nov. 6, 1936 d l 00Iw Jp/af0 f Patented July 2, 1940 7 2,206,061 RESPIRATOR Edward M. Splaine, Southbridge, Mass, assignor to American Optical Company, vSouthbridge,
Mass, setts a voluntary association of Massachu- Application November, 6, 1936, Serial No. 109,526
. 10 Claims.
This invention relates to respirators and more particularly to' respirators fitting the face and comprising a filter for removing particles of dust or the like from the air supplied to the user.
An object of the present invention is to so dispose the parts of the respirator with relation to the head of the user that there is minimum interference with vision.
In the accompanying drawing illustrating the invention, Fig. I is a perspective view of one of the various forms which the invention may assume, partly broken away to illustrate details;
Fig. II is a sectional view on line II-II of Fig. I; I
Fig. III is a sectional view on the line IIIIII of Fig. I; and Fig. IV is a developed view in perspective of the assembling of the inner end of a filter with an inlet to the face piece, all but the inner end of the filter being broken away and only a fragment of the face piece proper being shown.
The type of respirator to which thepresent invention particularly appertains is intended to remove from the air being breathed such. particles as lodge in a porous felt material through which the air is passed. A particularly troublesome problem with this type of respirator is the disposition of the filtering material so as not to interfere with the vision of the user. This problem arises out of the necessity for providing a filter or, filters having relativelyextensive super.- ficial area in order that the required volume of air may be passed and filtered Without making the user uncomfortable due to difficulty in drawing in the air through the respirator.
In accordance with the present invention a relatively large area of filtering material is disposed in such a way as to offer but slight obstruction to the view of the-user. The filtering material is made up into filtering means arranged to substantially encircle the head of the user, this filtering means being in communication with a face piece for supplying filtered air.
For the convenience and comfort of the user,
' the filtering means may be arranged so as to ex tend in opposite directions along the device, such as a strip, which is placed about the head of the user to maintain the face piece of the respirator in place.
Referring to the particular embodiment of the invention illustrated in the drawing, it will be noted that the face piece 5 is of such shape and contour as to fit over the nose and mouth of the user and provide air-tight contact with the face, without overlying the eye cavities. As shown,
the body portion of the face piece. is of metal such as aluminum, and sealing engagement with the face is afforded by a rubber flange 5a mountedon the rim of the body portion. One
or more exhalation valves 6 are provided on the to permit such discharge and will be reseated after such discharge so as to prevent air bein drawn in through the perforations 8.
The inlets I0 to the face piece may be formed.
integrally therewith, or may be separate elements secured in any suitable manner to the face piece 5. Each inlet I0 is so shaped as to fit theopen end of the filter l2 which suppliesl'filtered air thereto. In the illustrated embodiment each inlet N3 is relatively narrow, tapering fromfa rounded end at the bottom towards the top so that theside walls substantially meet at .the
top edge.
From the inlets l0 air is. admitted to the interior of the face piece .5 through perforations An inhalation valve l5 overlies the per-.
l4. forations M for each inlet, each valve l5 being. secured at its opposite ends, asindicated at IS. The inhalation valves l5 function in similar manner to the exhalation valves 6, except that they admit air instead of permitting the discharge of used air. r
While the .particular filtering material employed forms nopart of the present invention, I find that a relatively dense felt is a suitable material for this purpose. This felt may be formed into elongate filters l2 having substantially the cross section shown in Fig. III of the drawing. A light coil spring I8 extending-along the bottom portion of each filter I 2, as'illu strated in Figs. I and III, helps to keep these filters in expanded condition, even while the user is illustrated in Fig. I, the ends of the filters l2 are connected to the strap by slides 23 which permit sufiicient relative movement between the strap and the filters to permit the strap to accommodate itself to the head in use.
In case the filters l2 become fouled, or are otherwise rendered unfit for further service, they may be quickly replaced due to the arrangement for attaching them to the inlets l0. E ach inlet carries a series of prongs 25, which are so directed as to hook into the material of the respec tive filters. In addition, a clamp 26 is slidable along each filter so as to overlie the inlets I0, and more particularly, the prongs 25. Each clamp 26 has a reversely bent edge 21, which is adapted to engage with the inturned edge 28 of a coupling 28. When the two clamps 26 have been moved inwardly so as to hold the two filters l2 to the two inlets It], the coupling 29 may he slid downwardly in interlocked engagement with the reversely bent edges 21, thus firmly positioning the inner ends of the two filters on the two inlets ID. The coupling 29, when in position, overlies and shields the inhalation valve or valves 6.
A respirator embodying the present invention has the advantage of compactness without necessitating a reduction in the extent of superficial area of the filter material; the filters are quick ly detachable, so that it is not a cumbersome operation to replace them; and the arrangement of the filters in winged fashion disposes them in such a way as to interfere to a minimum extent with the vision of the user. Moreover, there is no looseness or flapping of the parts,
since the filters are supported in compact fashion from the strap or other device which maintains the face piece in place. The cross section of each wing of the filtering means affords the further advantage that the taper is from the bottom to the top, so that the outer side slopes away from the eye, thus giving greater freedom of vision.
While I have illustrated and described the erabodiment of my invention which I at present prefer, it will be understood that the invention ing a pair of opposed inlets, filters telescoping with said inlets, clamps slidable along said filters each to clamping position over the respective inlet, and a coupling for connecting said clamps together in clamping position.
2. A respirator comprising a face piece having a pair of opposed inlets, filters telescoping with said inlets, clamps slidable along said filters each to clamping position over the respective inlet, a coupling for connecting said clamps together in clamping position, and an exhalation valve shielded by said coupling.
. like face piece having an edge portion shaped to engage the face and having respiratory openings in the opposedside walls thereof, relatively long and slender horn-like filter means of filter material having filtering characteristics substantially throughout the entire area thereof, said horn-like filter means each having a relatively free closed end and an opening in the opposed end thereof with each of said ends having an opening therein being fitted about one of the respiratory openings of the face piece, means for holding said filter means on said face piece over said respiratory openings and supporting means for engaging the head and for holding the face piece on the face, said filter means each having a connection adjacent the closed end thereof with said supporting means whereby the filter means is held in relatively close relation with the face.
5. In a device of the character described a cuplike face piece having an edge portion shaped to engage the face and having respiratory openings in the opposed side walls thereof, relatively long and slendor horn-like filter means of filter material having filtering characteristics substarntially throughout the entire area thereof, said horn-like filter means each having a relatively free closed end and an opening in the opposed end thereof with each of said ends having an opening therein being fitted about one of the respiratory openings of the face piece, means for holding said filter means on said face piece over said respiratory openings and supporting means for engaging the head and for holding the face piece on the face, said filter means each having a connection adjacent the closed end thereof with said supporting means whereby the filter means is held in relatively close relation with the face and flexible means extending lengthwise of the filter means for normally tending to retain them in extended relation with the face piece.
6. In a device of the character described a face piece adapted to overlie the nose and mouth of the wearer and having an edge portion for engaging the face, said face piece having a respiratory opening therein, relatively long and narrow filter means having an open end overlying said respiratory opening and having its opposite end closed, said filter means being formed of relatively flexible filtering material having a filtering function substantially throughout the entire area thereof, connection means for holding said filter means on said face piece over said respiratory opening and band-like means encircling the head for holding said face piece on the face, said filter means having a connection with the band-like means adjacent the closed end thereof for holding the filter means in relatively close relation with the face.
'7. In a device of the character described a face piece adapted to overlie the nose and mouth of the wearer and having an edge portion for engaging the face, said face piece having a respiratory opening therein, relatively long and narrow filter means having an open end overlying said respiratory opening and having its opposite end closed, said filter means being formed of relatively flexible filtering material having a filtering function substantially throughout the entire area thereof, connection means for holding said filter means on said face piece over said respiratory opening and band-like means encircling the head for holding said face piece on the face, said filter means having a connection with the band-like means adjacent the closed end thereof for holding the filter means in relatively close relation with the face, and resilient supporting means secured to the face piece adjacent the respiratory opening and extending longitudinally of the filter means for normally holding it in extended relation with the face piece.
8. In a device of the character described, a face porting means encircling the head of the wearer piece adapted to overlie the nose and mouth of the wearer and having an edge portion for engaging the face, said face piece having a respiratory opening therein, relatively long and nar row horn-like filter means having an open end overlying the respiratory opening and having its opposite end closed, said filter means being formed of filtering material having a filtering function substantially throughout the entire area thereof, and supporting means for holding said filter means in relatively close relation with the face with the said filter means having a relatively flat surface for engaging the side .of the face and being extended substantially along the line of said supporting means with a connection adjacent the closed end thereof with said supporting means.
9. In a device of the character described, a face piece shaped to fit about the nose and mouth of the wearer and having an edge portion for engaging the face, said face piece having respiratory openings therein, horn-like filter means each having an open end portion fitting about one of said respiratory openings and each having its opposite end closed, said filter means having a filtering function substantially throughout the entire area thereof, common connection means for holding said filter means on said face piece over said respiratory openings and band-like supfor securing the facepiece to the face, said filter means extending substantially along the line of said band-like means and each having a con- .nection with said band-like means adjacent the closed ends thereof. I
10. In a device of the character described, a face piece shaped to fit about the nose and mouth of the wearer and having an edge portion for engaging the face, said face piece having respiratory openings therein, horn-like filter means each having an open end portion fitting about one closed ends thereof and resilient means extending longitudinally of said filter means for normally holding said filter means in extended relation with said face piece.
' EDWARD M. SPLAINE.
US109526A 1936-11-06 1936-11-06 Respirator Expired - Lifetime US2206061A (en)

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Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2811967A (en) * 1954-01-05 1957-11-05 Draegerwerk Ag Mask with dust filter
US4501272A (en) * 1981-10-30 1985-02-26 Shigematsu Works Co., Ltd. Mask
US4592350A (en) * 1982-11-08 1986-06-03 American Optical Corporation Respirator
US4603692A (en) * 1984-05-21 1986-08-05 Siebe North, Inc. Yoke for the harness of a respirator
US4850346A (en) * 1986-10-20 1989-07-25 Wgm Safety Corp. Respirator
US4886058A (en) * 1988-05-17 1989-12-12 Minnesota Mining And Manufacturing Company Filter element
US20020170563A1 (en) * 1992-05-29 2002-11-21 Japuntich Daniel A. Filtering face mask that has a new exhalation valve
US20070119459A1 (en) * 1992-05-29 2007-05-31 3M Innovative Properties Company Method Of Making A Filtering Face Mask Having New Exhalation Valve
US20070144123A1 (en) * 2005-12-22 2007-06-28 Angadjivand Seyed A Filter Element That Has Plenum Containing Bonded Continuous Filaments
USD779674S1 (en) 2015-02-27 2017-02-21 3M Innovative Properties Company Filter element having a connector
USD786443S1 (en) 2015-02-27 2017-05-09 3M Innovative Properties Company Filter element
USD792959S1 (en) 2015-02-27 2017-07-25 3M Innovative Properties Company Filter element having a pattern
US11311752B2 (en) 2015-02-27 2022-04-26 3M Innovative Properties Company Flexible filter element having an end outlet

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2811967A (en) * 1954-01-05 1957-11-05 Draegerwerk Ag Mask with dust filter
US4501272A (en) * 1981-10-30 1985-02-26 Shigematsu Works Co., Ltd. Mask
US4592350A (en) * 1982-11-08 1986-06-03 American Optical Corporation Respirator
US4603692A (en) * 1984-05-21 1986-08-05 Siebe North, Inc. Yoke for the harness of a respirator
US4850346A (en) * 1986-10-20 1989-07-25 Wgm Safety Corp. Respirator
USRE35062E (en) * 1988-05-17 1995-10-17 Minnesota Mining And Manufacturing Company Filter element
US4886058A (en) * 1988-05-17 1989-12-12 Minnesota Mining And Manufacturing Company Filter element
US7428903B1 (en) * 1992-05-29 2008-09-30 3M Innovative Properties Company Fibrous filtration face mask having a new unidirectional fluid valve
US20020170563A1 (en) * 1992-05-29 2002-11-21 Japuntich Daniel A. Filtering face mask that has a new exhalation valve
US6843248B2 (en) 1992-05-29 2005-01-18 3M Innovative Properties Company Filtering face mask that has a new exhalation valve
US20070119459A1 (en) * 1992-05-29 2007-05-31 3M Innovative Properties Company Method Of Making A Filtering Face Mask Having New Exhalation Valve
US7493900B1 (en) * 1992-05-29 2009-02-24 3M Innovative Properties Company Fibrous filtration face mask having a new unidirectional fluid valve
US7311104B2 (en) 1992-05-29 2007-12-25 3M Innovative Properties Company Method of making a filtering face mask that has an exhalation valve
US20070144123A1 (en) * 2005-12-22 2007-06-28 Angadjivand Seyed A Filter Element That Has Plenum Containing Bonded Continuous Filaments
WO2007075725A1 (en) 2005-12-22 2007-07-05 3M Innovative Properties Company Filter element that has plenum containing bonded continuous filaments
US9216306B2 (en) 2005-12-22 2015-12-22 3M Innovative Properties Company Filter element that has plenum containing bonded continuous filaments
USD779674S1 (en) 2015-02-27 2017-02-21 3M Innovative Properties Company Filter element having a connector
USD786443S1 (en) 2015-02-27 2017-05-09 3M Innovative Properties Company Filter element
USD792959S1 (en) 2015-02-27 2017-07-25 3M Innovative Properties Company Filter element having a pattern
USD886273S1 (en) 2015-02-27 2020-06-02 3M Innovative Properties Company Filter element having a pattern
US11311752B2 (en) 2015-02-27 2022-04-26 3M Innovative Properties Company Flexible filter element having an end outlet
US11738218B2 (en) 2015-02-27 2023-08-29 3M Innovative Properties Company Flexible filter element having an end outlet

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