US2112270A - Respirator - Google Patents

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US2112270A
US2112270A US722619A US72261934A US2112270A US 2112270 A US2112270 A US 2112270A US 722619 A US722619 A US 722619A US 72261934 A US72261934 A US 72261934A US 2112270 A US2112270 A US 2112270A
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respirator
bulbous
exhaust valve
valve
openings
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US722619A
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Harvey S Cover
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Priority to US744879A priority patent/US2106795A/en
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    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61MDEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
    • A61M16/00Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
    • A61M16/06Respiratory or anaesthetic masks
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61MDEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
    • A61M16/00Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
    • A61M16/10Preparation of respiratory gases or vapours
    • A61M16/105Filters
    • A61M16/106Filters in a path
    • A61M16/107Filters in a path in the inspiratory path

Definitions

  • My invention relates broadly to respirators and has for an objectV ⁇ the provision of such a device having a novel type exhaust valve and a novel construction of the respirator body for the pur- 5 pose of attaching and securing the exhaust valve thereto.
  • This invention is. broadly related to my copending applications, Serial Nos. 662,929, 684,503, and 684,968, filed respectively on March 2'?, 1933, August 10, 1933, and August 14. 1933.
  • Another object is the provision of a respirator and means for protecting the exhaust valve from damage and also protecting it to a high degree from the entrance of foreign ⁇ particles which might interfere with the proper working of the exhaust valve parts. It might be thought that the accomplishment of these objects would be ac-y My invention may be best understood by refer- 4 ence to the accompanying drawings, ln whichz.
  • Figi 1 is a top plan view of my device;
  • Fig. 2 is a side elevational view of the device;
  • FIG. 3 is a perspective view of the face contactv member which maybe employed in conjunction with my device
  • Fig. 4 is a sectional view taken substantially on the line l-I of Fig. 2;
  • Fig. 5 is a sectional view taken substantially on the line 5--5 of Fig. 2;
  • Fig. 6 is a sectional view taken substantially on the line-6 6 of Fig. 1;
  • Fig. 7 is a sectional view taken substantially on the line 1-1 of Fig. 2;
  • Fig. 8 is a detail view in section of a modied form of exhaust valve and respirator parts for attaching the valve to the respirator;
  • Fig. 9 is a sectional viewtaken substantially on the line 9-9 of,l Fig. 8.
  • the preferred form ⁇ of my device comprises a unitary wedge ⁇ shaped main body Ill having oppositely inclined andconverging side faces II and-
  • the entire body portion I0 including side faces II and I2 and upper and lower faces I3 is preferably moulded into one piece of exible and resilient rubber so that the side walls 5 may fold against each other when not in use in order to occupy a minimum amount of space and be'adapted to be carried in a pocket.
  • Upper and lower faces I3 are provided with identical cutouts I4.
  • the function of cut-outs I4 is to permit the entrance of and t tightly around the bridge of the users nose. Since the cut-outs are identical the device may be rotated throughv,
  • Face contact member I6 is generally frustoconical in shape and knitted into a continuous elongated band. Attaching loops I1 are provided at points one hundred eighty degrees apart, ad-
  • the member I6 may then be attached to the respirator by inserting the smaller end into the open or rear end of the respirator and turning the larger end outwardly and over the rear edges of side faces II and I2 and upper and lower faces I3. When this operation is completed so that the member I6 covers entirely said rear edges the attaching loops I1 may be' hooked onto the forwardly inclined securing lugs I5.
  • Supporting straps I8 land .I9 may be secured to opposite side faces II and l2 respectively at points adjacent but forwardly of the rear edges of said side faces. Attaching bolts 20 may be used for this purpose and because of the positioning of said bolts they do not interfere with the outward and forward folding of face contact member I6 to any detrimental extent.
  • a securing buckle 2l is carried by strap I8 and cooperates with the free end of strap I9. are of course of sufficient length to extend around the head of the user ⁇ so as to attach the respirator securely in place for ltering the inhaled air.
  • Oppositely inclined side faces II and I2 are provided with inhaling apertures 22 and 23.
  • these apertures are of large size and ar" ranged in a circular formation withone aperture serving as the imaginary axis of the circular formation.
  • Extending entireley around the groups of apertures 22 and 23 are outwardly extending Straps I8 and I9 annular flanges 24 and 25 respectively, and a plurality of transversely extending 'attaching bosses 26 and 21 protrude at spaced points from the outer faces of flanges 24 and 25 respectively.
  • the flanges 24 and 25 are formed ⁇ inte grally with the side faces II and I2 respectively and of the same character of material.
  • the flanges 24 and 25 may be made of greater thickness than the side faces so as to make them relatively more stiff and less subject to deformation.
  • Filtering material 28 is arranged over apertures 22 and 23 and within the flanges 24 and 25.
  • VScreens 29 may be placed over the outer ends of said flanges so as to hold filtering material 28 in place.
  • Caps 30 having enlarged annular openings 3I may be placed over screens 29 and flanges 24 and 25 and attached to said flanges by the entrance of attaching 'bosses or lugs 26 and 21 into the slots 32 which are carried in the cylindrical faces of caps 30.
  • Caps 30 are preferably attached by compressing anges 24 and 25 so that the attaching lugs 26 and 21 may be brought within the cylindrical walls of caps 30 and when the lugs 26 and 21 are in alignment with slots 32 the resilience of the flange material causes the attaching lugs to be projected outwardly and through the slots 32.
  • the caps may be removed l' pressing the lugs-inwardly and through slots
  • the faces I I and I2 and upper and lower faces I3 extend forwardly and into a Wall forming a bulbous extension 33.
  • the bulbous extension 33 is preferably longer from top to bottom than,
  • Annular openings 34 are provided at the top and bottom of bulbous extension 33 for the purpose of permitting the exit ,of exhaled air and so placed as to permit drainage of Water of condensation from the interior bulbous chamber.
  • the interior wall of the bulbous extension 33 is thickened so as to provide an abutting and retaining bead 35 whose function is to serve as van abutment against which the exhaust valve carrying frame 36 is adapted to be held.
  • Retaining lugs ⁇ 31 are spaced forwardly of bead 35 on the interior wall ofbulbous extension 33 and are preferably arranged on opposite walls of said extension.
  • the exhaust valve frame 36 heretofore mentioned comprises a somewhat ovally shaped base plate 39 and the forwardly extending flange 38 heretofore mentioned. Spaced exhaust openings 40 are placed adjacent opposite ends of plate'39 and because of the positioning of valve frame 36 are adjacent the upper and lower walls of bulbous extension 33.v
  • flap 4I is preferably made from a thin sheet of extremely flexible and resilient rubber material and is of sufcient size to cover, entirely, openings 40.
  • the pins 42 are preferably placed intermediate the openings 40 and act as a hinge upon which opposite ends of flap 4I virtually pivot when air is exhaled from the respirator. Because of the flexibility and resilience of the flap 4I the opposite ends thereof immediately return to lie flat upon the forward face of base plate 39 when pressure within the respirator is reduced to that existing outside the respirator. As soon as inhalation starts the flap 4I is drawn tightly against the plate 39 because Figs.
  • a respirator comprising a forwardly tapered main body portion formed of flexible material and a bulbous chamber formed integrally therewith at its forward end, there being a constricted passageway formed between the body portion and. said chamber, the flexible walls of the bulbous chamber adjacent said passage being formed to provide a valve frame seat, a valve fram'e and valve, and means for retaining said valve frame on'said seat, said valve frame and valve being removable by flexing the'walis of the chamber and passing the valve frame and valve through said constricted passageway, 'substantially as described.
  • a respirator comprisingl a pair of forwardly tapered flexible side walls connected at their longitudinal edges forming a larger open rear end for engaging over the breathing openings of the face and a smaller forward end, the forward end being expanded into a Vvertically elongated bulbous chamber arranged with its major axis vertical and having an exhaust opening at each end thereof, there being a constricted passageway between said chamber andthe remaining portion of the device, and a one-way valve de- 'edges and adapted to tachably mounted in said chamberand adapted to be removed through said constricted passageway, substantially as described.
  • a respirator comprising a main'body por-- tion formed of a pair of forwardly tapered nexiblelside walls connected at their longitudinal fold against each other, and said body portici: being expandedv forwardly at the ends of the side walls to form a vertically elongated bulbous chamber, said chamber being closed at the front and havingan' exhaust opening at both upper and lower ends. and a one-way valve mounted in said chamber, in which respirator the bulbous chamber is provided with an inwardly opening annular seat adjacent the constricted opening and a rigid exhaust valve frame removably held in said seat and a valve carried by said frame, substantially as described.
  • a respirator comprising a similar openings atthe upper and lower ends thereof, each constituting both an exhaust and a drain port, and an exhaust valve andrigid valve frame mounted in said bulbous chamber and removable through said body portion, substantially as described.

Description

H. S. COVER March 29, 1938.
I RESPIRATOR Filed April 27, 1934 2 Sheets-Sheet 1 H. S. COVER March 29, 1938.
RESPIRATOR Filed April 27, 1934 2 Sheets-Sheet 2 Patented Mar. Z9,l 1938 UNITED sTATEs PATENT oFFlcE BESPIRATOR Harvey S. Cover, South Bend, Ind. Application April 27, 1934, Serial No. 722,619
4 Claims.
My invention relates broadly to respirators and has for an objectV` the provision of such a device having a novel type exhaust valve and a novel construction of the respirator body for the pur- 5 pose of attaching and securing the exhaust valve thereto. This invention is. broadly related to my copending applications, Serial Nos. 662,929, 684,503, and 684,968, filed respectively on March 2'?, 1933, August 10, 1933, and August 14. 1933.
Another object is the provision of a respirator and means for protecting the exhaust valve from damage and also protecting it to a high degree from the entrance of foreign `particles which might interfere with the proper working of the exhaust valve parts. It might be thought that the accomplishment of these objects would be ac-y My invention may be best understood by refer- 4 ence to the accompanying drawings, ln whichz.
Figi 1 is a top plan view of my device; Fig. 2 is a side elevational view of the device;
f Fig. 3 is a perspective view of the face contactv member which maybe employed in conjunction with my device; 3
Fig. 4 is a sectional view taken substantially on the line l-I of Fig. 2;
Fig. 5 is a sectional view taken substantially on the line 5--5 of Fig. 2;
Fig. 6 is a sectional view taken substantially on the line-6 6 of Fig. 1;
Fig. 7 is a sectional view taken substantially on the line 1-1 of Fig. 2;
Fig. 8 is a detail view in section of a modied form of exhaust valve and respirator parts for attaching the valve to the respirator; and
Fig. 9 is a sectional viewtaken substantially on the line 9-9 of,l Fig. 8.
, Referring now'to Figs. 1 and 2, the preferred form`of my device comprises a unitary wedge` shaped main body Ill having oppositely inclined andconverging side faces II and- |.2 which are joined together by similarly formed upper and lower faces I3. The entire body portion I0 including side faces II and I2 and upper and lower faces I3 is preferably moulded into one piece of exible and resilient rubber so that the side walls 5 may fold against each other when not in use in order to occupy a minimum amount of space and be'adapted to be carried in a pocket. Upper and lower faces I3 are provided with identical cutouts I4. The function of cut-outs I4 is to permit the entrance of and t tightly around the bridge of the users nose. Since the cut-outs are identical the device may be rotated throughv,
substantially one hundred yeighty degrees and yet ft the wearers face efficiently in one position as well as the other. y
Forwardly inclined lugs I5are arranged on upper and lower faces I3 for the purpose of anchoring face contact member I6 which is shown in Fig. 3 before attachment to the respirator. Face contact member I6 is generally frustoconical in shape and knitted into a continuous elongated band. Attaching loops I1 are provided at points one hundred eighty degrees apart, ad-
jacent the larger end of member I6. The member I6 may then be attached to the respirator by inserting the smaller end into the open or rear end of the respirator and turning the larger end outwardly and over the rear edges of side faces II and I2 and upper and lower faces I3. When this operation is completed so that the member I6 covers entirely said rear edges the attaching loops I1 may be' hooked onto the forwardly inclined securing lugs I5.
Supporting straps I8 land .I9 may be secured to opposite side faces II and l2 respectively at points adjacent but forwardly of the rear edges of said side faces. Attaching bolts 20 may be used for this purpose and because of the positioning of said bolts they do not interfere with the outward and forward folding of face contact member I6 to any detrimental extent. A securing buckle 2l is carried by strap I8 and cooperates with the free end of strap I9. are of course of sufficient length to extend around the head of the user` so as to attach the respirator securely in place for ltering the inhaled air.
Oppositely inclined side faces II and I2 are provided with inhaling apertures 22 and 23. Preferably these apertures are of large size and ar" ranged in a circular formation withone aperture serving as the imaginary axis of the circular formation. Extending entireley around the groups of apertures 22 and 23 are outwardly extending Straps I8 and I9 annular flanges 24 and 25 respectively, and a plurality of transversely extending 'attaching bosses 26 and 21 protrude at spaced points from the outer faces of flanges 24 and 25 respectively. Preferably the flanges 24 and 25 are formed `inte grally with the side faces II and I2 respectively and of the same character of material. However, the flanges 24 and 25 may be made of greater thickness than the side faces so as to make them relatively more stiff and less subject to deformation. Filtering material 28 is arranged over apertures 22 and 23 and within the flanges 24 and 25. VScreens 29 may be placed over the outer ends of said flanges so as to hold filtering material 28 in place. Caps 30 having enlarged annular openings 3I may be placed over screens 29 and flanges 24 and 25 and attached to said flanges by the entrance of attaching 'bosses or lugs 26 and 21 into the slots 32 which are carried in the cylindrical faces of caps 30. Caps 30 are preferably attached by compressing anges 24 and 25 so that the attaching lugs 26 and 21 may be brought within the cylindrical walls of caps 30 and when the lugs 26 and 21 are in alignment with slots 32 the resilience of the flange material causes the attaching lugs to be projected outwardly and through the slots 32. The caps may be removed l' pressing the lugs-inwardly and through slots The faces I I and I2 and upper and lower faces I3 extend forwardly and into a Wall forming a bulbous extension 33. The bulbous extension 33 is preferably longer from top to bottom than,
from side to side so as to offer very slight obstruction to the vision of the user. Annular openings 34 are provided at the top and bottom of bulbous extension 33 for the purpose of permitting the exit ,of exhaled air and so placed as to permit drainage of Water of condensation from the interior bulbous chamber. Referring now to Figs. 6 and 7, the interior wall of the bulbous extension 33 is thickened so as to provide an abutting and retaining bead 35 whose function is to serve as van abutment against which the exhaust valve carrying frame 36 is adapted to be held. Retaining lugs `31 are spaced forwardly of bead 35 on the interior wall ofbulbous extension 33 and are preferably arranged on opposite walls of said extension. 'I'he bead 35 and lugs 31 thus in effect provide a retaining groove in which the exhaust valve frame 36 is constrictively held because the space between the forward edge of bead 35 and l the rearward edge of lugs 31 is somewhat less tlan the width of flange 38 of exhaust valve frame 3 Referring now to Figs. 4 and 5, the exhaust valve frame 36 heretofore mentioned comprises a somewhat ovally shaped base plate 39 and the forwardly extending flange 38 heretofore mentioned. Spaced exhaust openings 40 are placed adjacent opposite ends of plate'39 and because of the positioning of valve frame 36 are adjacent the upper and lower walls of bulbous extension 33.v
Consequently they are near annular openings 34 and moisture of condensation may find exit from the interior of the respirator through openings 49 and openings 34. identically the same manner regardless of whether the respirator is used in the position in which it is shown in Fig. 2 or whether it is rotated through one hundred eighty degrees. The outer perimeter of ange 381s somewhat greater than the inner perimeter of the wall of bulbous extension 33 which lies between lug 31 and bead 35. Consequently the flange is constrictivelyretained at These openings function in this point and an air-tight connection results. An exhaust valve disc or flap is secured to the forward face of base pins 42. 'Ihe disc or flap 4I is preferably made from a thin sheet of extremely flexible and resilient rubber material and is of sufcient size to cover, entirely, openings 40. The pins 42 are preferably placed intermediate the openings 40 and act as a hinge upon which opposite ends of flap 4I virtually pivot when air is exhaled from the respirator. Because of the flexibility and resilience of the flap 4I the opposite ends thereof immediately return to lie flat upon the forward face of base plate 39 when pressure within the respirator is reduced to that existing outside the respirator. As soon as inhalation starts the flap 4I is drawn tightly against the plate 39 because Figs. 8 and 9 and would be adaptable for use with a respirator having a bulbous extension which is circular in cross-section so that the bead 43 and spaced lugs 44 would provide an annular groove v for the retention of annular exhaust valve frame 45. The base plate 46 in such a construction would of course be circular as would the flange 41. Exhaust openings 48 might then be arranged around the attaching pin 49 as an axis and the flap or disc 56 could be held in place by pin 49 and rotate freely on said pin without danger of dragging upon the inner wall of flange 41. I prefer the form` illustrated in Figs. 1, et cetera, to the form shown in Figs. 8 and 9 because there is less obstruction to the vision when those forms of exhaust valves and bulbous extensions are used.
The removal of the exhaust valve frames from `the bulbous extensions is a relatively simple pushing it into the bulbous extension edgewise,
pressing one side of the frame into the retaining groove, and then deforming the wall of the bulbousy extension sufficiently to permit the other side of the valve frame to be forced into the retaining groove. l
From the foregoing description it can be seen that I have accomplished my objects in an extremely economical manner and provided a device which may be used for the intended purpose of filtering inhaled air without any great discomfort to the user. The latter feature is aided by the use'of two incoming filter chambers of large area. and the use of a quick acting and easily operated exhaust valve. The placing o'f the exhaust valve immediately forwardly of the nostrils and mouth of the user aids considerably in permitting the user to breathe lightly and freely and yetbe protected from the dangerous effects" of noxious gases and foreign particles.
While I have illustrated and described the preplate 39 by a pair of spaced ierred form of construction for carrying my invention into effect, this is capable of variation and modification without departing. from the spirit of the invention. I, therefore, do not wish to be limited to the precise details of construction set forth, but desire to avail myself of such variations and modifications as come within the scope of the appended claims.
Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:
1. A respirator comprising a forwardly tapered main body portion formed of flexible material and a bulbous chamber formed integrally therewith at its forward end, there being a constricted passageway formed between the body portion and. said chamber, the flexible walls of the bulbous chamber adjacent said passage being formed to provide a valve frame seat, a valve fram'e and valve, and means for retaining said valve frame on'said seat, said valve frame and valve being removable by flexing the'walis of the chamber and passing the valve frame and valve through said constricted passageway, 'substantially as described.
2. A respirator comprisingl a pair of forwardly tapered flexible side walls connected at their longitudinal edges forming a larger open rear end for engaging over the breathing openings of the face and a smaller forward end, the forward end being expanded into a Vvertically elongated bulbous chamber arranged with its major axis vertical and having an exhaust opening at each end thereof, there being a constricted passageway between said chamber andthe remaining portion of the device, and a one-way valve de- 'edges and adapted to tachably mounted in said chamberand adapted to be removed through said constricted passageway, substantially as described.
3. A respirator comprising a main'body por-- tion formed of a pair of forwardly tapered nexiblelside walls connected at their longitudinal fold against each other, and said body portici: being expandedv forwardly at the ends of the side walls to form a vertically elongated bulbous chamber, said chamber being closed at the front and havingan' exhaust opening at both upper and lower ends. and a one-way valve mounted in said chamber, in which respirator the bulbous chamber is provided with an inwardly opening annular seat adjacent the constricted opening and a rigid exhaust valve frame removably held in said seat and a valve carried by said frame, substantially as described.
4. A respirator comprising a similar openings atthe upper and lower ends thereof, each constituting both an exhaust and a drain port, and an exhaust valve andrigid valve frame mounted in said bulbous chamber and removable through said body portion, substantially as described. Y
- HARVEY S. COVER.
body portion con-l structed oi' a pair of forwardly tapered flexiblel
US722619A 1934-04-27 1934-04-27 Respirator Expired - Lifetime US2112270A (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4628927A (en) * 1983-11-22 1986-12-16 Ward Russell G Reversible face mask with replaceable air filter insert
US6701925B1 (en) 2002-04-11 2004-03-09 Todd A. Resnick Protective hood respirator
US7117868B1 (en) 1992-05-29 2006-10-10 3M Innovative Properties Company Fibrous filtration face mask having a new unidirectional fluid valve
US20070119459A1 (en) * 1992-05-29 2007-05-31 3M Innovative Properties Company Method Of Making A Filtering Face Mask Having New Exhalation Valve
USRE43289E1 (en) * 1995-08-04 2012-04-03 3M Innovative Properties Company Uni-directional fluid valve

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4628927A (en) * 1983-11-22 1986-12-16 Ward Russell G Reversible face mask with replaceable air filter insert
US7117868B1 (en) 1992-05-29 2006-10-10 3M Innovative Properties Company Fibrous filtration face mask having a new unidirectional fluid valve
US20070119459A1 (en) * 1992-05-29 2007-05-31 3M Innovative Properties Company Method Of Making A Filtering Face Mask Having New Exhalation Valve
US7428903B1 (en) 1992-05-29 2008-09-30 3M Innovative Properties Company Fibrous filtration face mask having a new unidirectional fluid valve
US7493900B1 (en) 1992-05-29 2009-02-24 3M Innovative Properties Company Fibrous filtration face mask having a new unidirectional fluid valve
USRE43289E1 (en) * 1995-08-04 2012-04-03 3M Innovative Properties Company Uni-directional fluid valve
US6701925B1 (en) 2002-04-11 2004-03-09 Todd A. Resnick Protective hood respirator

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