US2888012A - Respirator valve assembly - Google Patents

Respirator valve assembly Download PDF

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US2888012A
US2888012A US618950A US61895056A US2888012A US 2888012 A US2888012 A US 2888012A US 618950 A US618950 A US 618950A US 61895056 A US61895056 A US 61895056A US 2888012 A US2888012 A US 2888012A
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valve member
seat
rivet
web means
valve
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Glen M Larson
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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
    • A62B18/08Component parts for gas-masks or gas-helmets, e.g. windows, straps, speech transmitters, signal-devices
    • A62B18/10Valves

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  • RESFIRATOR VALVE ASSEMBLY Filed Oct. 29, 1956 /N VNTOR. GLEN M. LARSON I BY H15 HTTORNEY. Heme/s, KIECH, FOSTER a HHPR/S United States Patent RESPIRATOR VALVE ASSEMBLY Glen M. Larson, Los Angeles County, Calif.
  • This invention relates to a respirator facepiece assembly, and, more particularly, to such assembly having a novel exhalation valve means therein.
  • a further object of the invention is to provide such a valve mechanism which is positive in its sealing action yet will open readily.
  • To accomplish this I provide a thin flexible valve member, and annular seats against which the valve member is adapted to seal.
  • Another object is to provide such a valve mechanism in which the valve member may be readily replaced as desired.
  • Still another object of the invention is to provide such a valve mechanism which is simple and economical to make, assemble, and operate.
  • Fig. 1 is a front elevational view of a facepiece embodying the invention
  • Fig. 2 is a vertical sectional view taken on the line 22 of Fig. 1;
  • Fig. 3 is a plan view taken on the line 3-3 of Fig. 2;
  • Fig. 4 is an enlarged sectional view of one of the valve mechanisms of the invention taken on the line 4-4 of Fig. 3;
  • Fig. 5 is an inside elevational view taken on the line 55 of Fig. 2.
  • a facepiece 10 preferably stamped or otherwise formed of thin metal, includes a flat front wall 11 having an intake port 12 therein adapted to contain a suitable filter or purifying canister or other air supply.
  • the facepiece also has side walls 13 and 14, a curved top wall 15, and a flat bottom wall 16.
  • the bottom wall 16 has two circular openings 18 in each of which is a web means 20 consisting of webs 21 spanning the opening and connected together at their inner ends to form a central portion 22 having a hole 23 therein concentric with the opening.
  • a web means 20 consisting of webs 21 spanning the opening and connected together at their inner ends to form a central portion 22 having a hole 23 therein concentric with the opening.
  • an annular seat 25 Surrounding each of the openings 18 is an annular seat 25 which is recessed inwardly below the plane of the bottom wall 16.
  • each of the webs 21 is offset inwardly below the plane of the seat 25.
  • Formed in the [central portion 22 of the web means 20 and encircling the hole 23 is an annular bead 26.
  • a rivet 27 having an enlarged head 28 on its outer end and an outturned flange 29 on its inner end. Surrounding the rivet 27 and located between the flange 29 and the central portion 22 compression to bias the rivet inwardly.
  • a circular valve member 32 Disposed between the head 28 of the rivet 27 and the web means 20 is a circular valve member 32, which is formed of a thin, flexible, resilient normally flat material, such as rubber, and which is preferably about twenty thousandths of an inch thick, or less.
  • the valve member 32 has a central orifice 33 which may be about the same diameter as the hole 23 but is smaller than the diameter of the head 28 and the annular head 26.
  • the valve member 32 has an outer annular portion 34 adapted to engage and seat on the annular seat 25.
  • the valve member 32 may be installed by moving the rivet 27 outwardly against the action of the spring 30 and then expanding the orifice 33 over the rivet head 28 to allow the valve member to be snapped into its assembled position shown in Fig. 4.
  • the valve member 32 may be readily removed, to permit a new valve member to be substituted or otherwise, merely by reversing this procedure.
  • the rivet head 28 In the assembled position shown in Fig. 4, the rivet head 28, under the biasing action of the spring 30, clamps an inner annular portion of the valve member between [the rivet head and the annular bead 26 to form a fluid seal around the hole 23 and orifice 33, which is a feature of the invention.
  • the rivet 27 normally distorts the valve member 32 into the slightly conical form shown in Fig. 4 to draw the outer annular portion 34 thereof against the valve seat 25 to effect a fluid seal therebetween.
  • annular space 35 which separates the valve member from the webs 21. This insures that any internal fluid pressure on the valve member 32 will be uniformly applied to substantially all of the area thereof, and further prevents possibly damaging contact between the valve member and the webs 21, which are additional objects of the invention.
  • annular valve seat 25 is recessed below the plane of the bottom wall 16 a distance greater than the thickness of the valve member 32, and this is another feature of the invention as it protects the valve member against possible damage due to scuffing of the facepiece against foreign objects.
  • the facepiece 10 is designed to be fitted over the nose and mouth of a wearer. It is to be noted that in use the circular openings 18 in the lower wall 16 are generally aligned with the nostrils of the wearer so that if the wearers breath is exhaled through his nose the air will impinge directly on the inner surfaces of the valve members 32, which facilitates opening thereof.
  • a respirator facepiece assembly the combination of: a hollow facepiece adapted to fit over the nose and mouth of a wearer, and having a lower wall adapted to be disposed beneath the nostrils and mouth of a wearer, said lower wall having a circular opening and an annular seat recessed inwardly from the outside of said wall and between said opening and the major portion of said wall; web means secured to said seat and spanning said opening, said web means having a central portion provided with a hole concentric with said seat, said web means sloping inwardly away from said seat; a thin circular resilient valve member the outer annular portion of which is adapted to engage said seat to form a seal therebetween but distortable outwardly to allow fluid to pass between said valve member and said seat, said valve member having a central orifice axially aligned with said hole; a rivet extending through said orifice and said hole, having a head on its outer end adapted to engage the outer surface of said valve member, and extending inwardly into said facepiece a
  • a respirator facepiece assembly the combination of: a hollow facepiece adapted to fit over the nose and mouth of a wearer, and having a lower wall adapted to be disposed beneath the nostrils and mouth of a wearer, said lower wall having a circular opening and an annular seat recessed inwardly from the outside of said wall and between said opening and the major portion of said wall; web means secured to said seat and spanning said opening, said web means having a central portion provided with a hole concentric with said seat, said web means sloping inwardly away from said seat; a thin circular resilient valve member the outer annular portion of which is adapted to engage said seat to form a seal therebetween but distortable outwardly to allow fluid to pass between said valve member and said seat, said valve member having a central orifice axially aligned with said hole; a rivet extending through said orifice and said hole, having a head on its outer end adapted to engage the outer surface of said valve member, and extending inwardly into said facepiece a
  • a respirator facepiece assembly the combination of: a hollow facepiece adapted to fit over the nose and mouth of a wearer, and having a lower wall adapted to be disposed beneath the nostrils and mouth of a wearer, said lower wall having a pair of circular openings side by side, and having a pair of annular seats recessed inwardly from the outside of said wall, each of said seats being between one of said openings and the major portion of said wall; web means secured to each of said seats and spanning its associated opening, each of said web means having a central portion provided with a hole concentric its opening, each said web means sloping inwardly away from its associated seat; a pair of thin circular resilient valve members the outer annular portion of each of which is adapted to engage one of said seats to form a seal therebetween but distortable outwardly to allow air to pass between that valve member and its said seat, each said valve member having a central orifice axially aligned with the hole in the associated web means; a pair of rivets each of
  • an annular valve seat providing an opening therein; web means secured to said seat and spanning said opening, said web means having a central portion provided with a hole concentric with said seat; a thin circular resilient valve member the outer annular portion of which is adapted to engage said seat to form a seal therebetween but distortable outwardly to allow fluid to pass between said valve member and said seat, said valve member having a central orifice axially aligned with said hole; a rivet extending through said orifice and said hole, having a head on its outer end adapted to engage the outer surface of said valve member, and extending inwardly a substantial distance beyond said web means; and spring means disposed between said rivet and said web means and adapted to bias said rivet inwardly so that its head normally maintains the outer annular portion of said valve member in sealing engagement with said seat and the central portion of said valve member in engagement with said web means, said rivet being outwardly movable against the action of said spring means.
  • an annular valve seat providing an opening therein and recessed inwardly from adjoining body portions of the valve; web means secured to said seat and sloping inwardly from said seat, said web means having a central portion provided with a hole concentric with said seat; a thin circular resilient valve member the outer annular portion of which is adapted to engage said seat to form a seal therebetween but distortable outwardly .to allow fluid to pass between said valve member and said seat, said valve member having a central orifice axially aligned with said hole; a rivet extending through said orifice and said hole, having a head on its outer end adapted to engage the outer surface of said valve member, and extending inwardly a substantial distance beyond said web means; and spring means disposed between said rivet and said web means and adapted to bias said rivet inwardly so that its head normally maintains the outer annular portion of said valve member in sealing engagement with said seat and the central portion of said valve member in sealing engagement with said web means, said rivet being

Description

May 26, 1959 G. M. LARSON 2,888,012
RESFIRATOR VALVE ASSEMBLY Filed Oct. 29, 1956 /N VNTOR. GLEN M. LARSON I BY H15 HTTORNEY. Heme/s, KIECH, FOSTER a HHPR/S United States Patent RESPIRATOR VALVE ASSEMBLY Glen M. Larson, Los Angeles County, Calif.
Application October 29, 1956, Serial No. 618,950
Claims. (Cl. 128-146) This invention relates to a respirator facepiece assembly, and, more particularly, to such assembly having a novel exhalation valve means therein.
It is conventional practice to provide protective masks for human wear with an exhalation valve mechanism through which the breath of the wearer may be exhaled. It is to be understood, however that my specific valve mechanism has other and different uses and its utility is not limited to the preferred embodiment disclosed herein.
It is a primary object of this invention to provide such a facepiece having an exhalation valve mechanism which will open readily with the imposition of extremely low fluid pressures, to insure a minimum of discomfort to and efiort by the wearer.
A further object of the invention is to provide such a valve mechanism which is positive in its sealing action yet will open readily. To accomplish this I provide a thin flexible valve member, and annular seats against which the valve member is adapted to seal. Another object is to provide such a valve mechanism in which the valve member may be readily replaced as desired.
Still another object of the invention is to provide such a valve mechanism which is simple and economical to make, assemble, and operate.
Other objects and advantages will appear from the drawing and the following specification, which are for the purpose of illustration only, and in which:
Fig. 1 is a front elevational view of a facepiece embodying the invention;
Fig. 2 is a vertical sectional view taken on the line 22 of Fig. 1;
Fig. 3 is a plan view taken on the line 3-3 of Fig. 2;
Fig. 4 is an enlarged sectional view of one of the valve mechanisms of the invention taken on the line 4-4 of Fig. 3; and
Fig. 5 is an inside elevational view taken on the line 55 of Fig. 2.
Referring to the drawing, a facepiece 10, preferably stamped or otherwise formed of thin metal, includes a flat front wall 11 having an intake port 12 therein adapted to contain a suitable filter or purifying canister or other air supply. The facepiece also has side walls 13 and 14, a curved top wall 15, and a flat bottom wall 16.
The bottom wall 16 has two circular openings 18 in each of which is a web means 20 consisting of webs 21 spanning the opening and connected together at their inner ends to form a central portion 22 having a hole 23 therein concentric with the opening. Surrounding each of the openings 18 is an annular seat 25 which is recessed inwardly below the plane of the bottom wall 16. As best shown in Fig. 4, each of the webs 21 is offset inwardly below the plane of the seat 25. Formed in the [central portion 22 of the web means 20 and encircling the hole 23 is an annular bead 26.
Extending through the hole 23 is a rivet 27 having an enlarged head 28 on its outer end and an outturned flange 29 on its inner end. Surrounding the rivet 27 and located between the flange 29 and the central portion 22 compression to bias the rivet inwardly.
Disposed between the head 28 of the rivet 27 and the web means 20 is a circular valve member 32, which is formed of a thin, flexible, resilient normally flat material, such as rubber, and which is preferably about twenty thousandths of an inch thick, or less. The valve member 32 has a central orifice 33 which may be about the same diameter as the hole 23 but is smaller than the diameter of the head 28 and the annular head 26. The valve member 32 has an outer annular portion 34 adapted to engage and seat on the annular seat 25. The valve member 32 may be installed by moving the rivet 27 outwardly against the action of the spring 30 and then expanding the orifice 33 over the rivet head 28 to allow the valve member to be snapped into its assembled position shown in Fig. 4. The valve member 32 may be readily removed, to permit a new valve member to be substituted or otherwise, merely by reversing this procedure.
In the assembled position shown in Fig. 4, the rivet head 28, under the biasing action of the spring 30, clamps an inner annular portion of the valve member between [the rivet head and the annular bead 26 to form a fluid seal around the hole 23 and orifice 33, which is a feature of the invention. Also, the rivet 27 normally distorts the valve member 32 into the slightly conical form shown in Fig. 4 to draw the outer annular portion 34 thereof against the valve seat 25 to effect a fluid seal therebetween. Due to the thin, flexible character of the valve member 32, slight internal fluid pressure thereon, as from the human breath, readily distorts the valve member outwardly away from the annular seat 25 to permit the passage of fluid therebetween and from the facepiece 10. When such fluid pressure is removed the valve member snaps back into its sealing position as shown in Fig. 4.
Between the valve member 32 and the major portion of the web means 20 there is an annular space 35 which separates the valve member from the webs 21. This insures that any internal fluid pressure on the valve member 32 will be uniformly applied to substantially all of the area thereof, and further prevents possibly damaging contact between the valve member and the webs 21, which are additional objects of the invention. It is also to be noted that the annular valve seat 25 is recessed below the plane of the bottom wall 16 a distance greater than the thickness of the valve member 32, and this is another feature of the invention as it protects the valve member against possible damage due to scuffing of the facepiece against foreign objects.
As diagrammatically illustrated in Fig. 2, the facepiece 10 is designed to be fitted over the nose and mouth of a wearer. It is to be noted that in use the circular openings 18 in the lower wall 16 are generally aligned with the nostrils of the wearer so that if the wearers breath is exhaled through his nose the air will impinge directly on the inner surfaces of the valve members 32, which facilitates opening thereof.
While I have shown and described a preferred embodiment of the invention, I do not intend to be limited thereto but desire to be afforded the full scope of the following claims:
I claim as my invention:
1. In a respirator facepiece assembly, the combination of: a hollow facepiece adapted to fit over the nose and mouth of a wearer, and having a lower wall adapted to be disposed beneath the nostrils and mouth of a wearer, said lower wall having a circular opening and an annular seat recessed inwardly from the outside of said wall and between said opening and the major portion of said wall; web means secured to said seat and spanning said opening, said web means having a central portion provided with a hole concentric with said seat, said web means sloping inwardly away from said seat; a thin circular resilient valve member the outer annular portion of which is adapted to engage said seat to form a seal therebetween but distortable outwardly to allow fluid to pass between said valve member and said seat, said valve member having a central orifice axially aligned with said hole; a rivet extending through said orifice and said hole, having a head on its outer end adapted to engage the outer surface of said valve member, and extending inwardly into said facepiece a substantial distance beyond said web means; and spring means disposed between said inner end of said rivet and said web means and adapted to bias said rivet inwardly so that its said head normally maintains the outer annular portion of said valve member in sealing engagement with said seat and the central portion of said valve member in engagement with said web means, said rivet being outwardly movable against the action of said spring means to permit said valve member to be removed therefrom by expanding said orifice over said head.
2. In a respirator facepiece assembly, the combination of: a hollow facepiece adapted to fit over the nose and mouth of a wearer, and having a lower wall adapted to be disposed beneath the nostrils and mouth of a wearer, said lower wall having a circular opening and an annular seat recessed inwardly from the outside of said wall and between said opening and the major portion of said wall; web means secured to said seat and spanning said opening, said web means having a central portion provided with a hole concentric with said seat, said web means sloping inwardly away from said seat; a thin circular resilient valve member the outer annular portion of which is adapted to engage said seat to form a seal therebetween but distortable outwardly to allow fluid to pass between said valve member and said seat, said valve member having a central orifice axially aligned with said hole; a rivet extending through said orifice and said hole, having a head on its outer end adapted to engage the outer surface of said valve member, and extending inwardly into said facepiece a substantial distance beyond said web means; and a coil spring around said rivet and disposed between said inner end of said rivet and said web means and adapted to bias said rivet inwardly so that its said head normally maintains the outer annular portion ofsaid valve member in sealing engagement with said seat and the central portion of said valve member in engagement with said web means, said rivet being outwardly movable against the action of said spring means to permit said valve member to be removed therefrom by expanding said orifice over said head.
3. In a respirator facepiece assembly, the combination of: a hollow facepiece adapted to fit over the nose and mouth of a wearer, and having a lower wall adapted to be disposed beneath the nostrils and mouth of a wearer, said lower wall having a pair of circular openings side by side, and having a pair of annular seats recessed inwardly from the outside of said wall, each of said seats being between one of said openings and the major portion of said wall; web means secured to each of said seats and spanning its associated opening, each of said web means having a central portion provided with a hole concentric its opening, each said web means sloping inwardly away from its associated seat; a pair of thin circular resilient valve members the outer annular portion of each of which is adapted to engage one of said seats to form a seal therebetween but distortable outwardly to allow air to pass between that valve member and its said seat, each said valve member having a central orifice axially aligned with the hole in the associated web means; a pair of rivets each of which extends through one of said orifices and its aligned hole, each of said rivets having a head on its outer end adapted to engage the outer surface of the associated valve member, and extending inwardly into said facepiece a substantial distance beyond the associated web means; and spring means disposed between the inner end of each of said rivets and its associated web means and adapted to bias each of said rivets inwardly so that its said head normally maintains the outer annular portion of its valve member in sealing engagement with its seat and its central portion in engagement with its associated web means, each of said rivets being outwardly movable against the action of said spring means to permit its associated valve member to be removed therefrom by expanding its said orifice over the head on its associated rivet.
4. In a valve construction, the combination of: an annular valve seat providing an opening therein; web means secured to said seat and spanning said opening, said web means having a central portion provided with a hole concentric with said seat; a thin circular resilient valve member the outer annular portion of which is adapted to engage said seat to form a seal therebetween but distortable outwardly to allow fluid to pass between said valve member and said seat, said valve member having a central orifice axially aligned with said hole; a rivet extending through said orifice and said hole, having a head on its outer end adapted to engage the outer surface of said valve member, and extending inwardly a substantial distance beyond said web means; and spring means disposed between said rivet and said web means and adapted to bias said rivet inwardly so that its head normally maintains the outer annular portion of said valve member in sealing engagement with said seat and the central portion of said valve member in engagement with said web means, said rivet being outwardly movable against the action of said spring means.
5. In a valve construction, the combination of: an annular valve seat providing an opening therein and recessed inwardly from adjoining body portions of the valve; web means secured to said seat and sloping inwardly from said seat, said web means having a central portion provided with a hole concentric with said seat; a thin circular resilient valve member the outer annular portion of which is adapted to engage said seat to form a seal therebetween but distortable outwardly .to allow fluid to pass between said valve member and said seat, said valve member having a central orifice axially aligned with said hole; a rivet extending through said orifice and said hole, having a head on its outer end adapted to engage the outer surface of said valve member, and extending inwardly a substantial distance beyond said web means; and spring means disposed between said rivet and said web means and adapted to bias said rivet inwardly so that its head normally maintains the outer annular portion of said valve member in sealing engagement with said seat and the central portion of said valve member in sealing engagement with said web means, said rivet being outwardly movable against the action of said spring means to permit its associated valve member to be removed therefrom by expanding its said orifice over the head on its associated rivet.
References Cited in the file of this patent UNITED STATES PATENTS 2,225,395 Young Dec. 17, 1940 2,505,173 Conley Apr. 25, 1950 FOREIGN PATENTS 875,747 Germany Mar. 26, 1953
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Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3014479A (en) * 1959-05-20 1961-12-26 Welsh Mfg Co Respirator
US3316904A (en) * 1961-07-31 1967-05-02 Minnesota Mining & Mfg Filtering web for face masks and face masks made therefrom
US4981134A (en) * 1990-01-16 1991-01-01 Courtney Darryl W Filtering face mask with inhalation/exhalation check valves
US5018519A (en) * 1990-08-03 1991-05-28 Brown Glenn E Mask for adminstering an anesthetic gas to a patient
US20020170557A1 (en) * 2001-05-08 2002-11-21 Schmidt James N. Mask with inhalation valve
US7004162B1 (en) 1992-11-09 2006-02-28 Canadian Monaghan, Ltd. Exhalation valve
US20060254592A1 (en) * 2005-01-28 2006-11-16 Bruce Anders Respiratory mask
USD874064S1 (en) 2018-05-18 2020-01-28 Trudell Medical International Mask
USD893806S1 (en) 2018-11-09 2020-08-18 Trudell Medical Internationl Mask and shroud
USD903097S1 (en) 2018-05-18 2020-11-24 Trudell Medical International Mask
US11439869B2 (en) 2017-05-19 2022-09-13 Trudell Medical International Positive expiratory pressure device

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2225395A (en) * 1940-06-26 1940-12-17 Acushnett Process Company Exhalation valve for gas masks
US2505173A (en) * 1948-12-24 1950-04-25 American Optical Corp Respirator
DE875747C (en) * 1951-08-07 1953-05-07 Andreas Loewe Automatic valve, especially pressure and suction valve for pumps

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2225395A (en) * 1940-06-26 1940-12-17 Acushnett Process Company Exhalation valve for gas masks
US2505173A (en) * 1948-12-24 1950-04-25 American Optical Corp Respirator
DE875747C (en) * 1951-08-07 1953-05-07 Andreas Loewe Automatic valve, especially pressure and suction valve for pumps

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3014479A (en) * 1959-05-20 1961-12-26 Welsh Mfg Co Respirator
US3316904A (en) * 1961-07-31 1967-05-02 Minnesota Mining & Mfg Filtering web for face masks and face masks made therefrom
US4981134A (en) * 1990-01-16 1991-01-01 Courtney Darryl W Filtering face mask with inhalation/exhalation check valves
US5018519A (en) * 1990-08-03 1991-05-28 Brown Glenn E Mask for adminstering an anesthetic gas to a patient
US7004162B1 (en) 1992-11-09 2006-02-28 Canadian Monaghan, Ltd. Exhalation valve
US7013896B2 (en) * 2001-05-08 2006-03-21 Trudell Medical International Mask with inhalation valve
US20020170557A1 (en) * 2001-05-08 2002-11-21 Schmidt James N. Mask with inhalation valve
US20060254592A1 (en) * 2005-01-28 2006-11-16 Bruce Anders Respiratory mask
US11439869B2 (en) 2017-05-19 2022-09-13 Trudell Medical International Positive expiratory pressure device
USD874064S1 (en) 2018-05-18 2020-01-28 Trudell Medical International Mask
USD890437S1 (en) 2018-05-18 2020-07-14 Trudell Medical International Mask
USD903097S1 (en) 2018-05-18 2020-11-24 Trudell Medical International Mask
USD893806S1 (en) 2018-11-09 2020-08-18 Trudell Medical Internationl Mask and shroud

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