Respiratory mask having a soft, compliant facepiece and a thin, rigid insert and method of making

• US 5,062,421 A
• Filed: 02/19/1991
• Issued: 11/05/1991
• Est. Priority Date: 11/16/1987
• Status: Expired due to Term

• Current Assignee: Minnesota Mining and Manufacturing Co (3M Company)
• Original Assignee: Minnesota Mining and Manufacturing Co (3M Company)
• Inventors: Burns, James A., Reischel, Joseph G.
• Primary Examiner(s): Burr, Edgar S.
• Assistant Examiner(s): Lewis, Aaron J.
• Application Number:
  US07/657,102
• Time in Patent Office: 259 Days
• Field of Search: 128/205.27, 128/206.12, 128/206.16, 128/206.17
• US Class Current: 128/205.27
• CPC Class Codes: A62B 18/025 Halfmasks A62B23/02 takes precedence; surgical face masks A41D13/11

Abstract

The novel respiratory mask has a soft, compliant facepiece to which is permanently sealed a relatively thin, rigid insert. The insert has swept back cheek portions, each formed with an aperture at which a filter cartridge is snapped into place through an opening in the facepiece. Adjacent said opening, the facepiece has a rigid which is bent over and stretched outwardly by the cartridge to create a hermetic seal. Each filter cartridge is asymmetric and swept back to shift the center of gravity inwardly toward the wearer'"'"'s head, thus making the mask seem to be lighter to a wearer than is a conventional respiratory mask of equal weight which has a center of gravity in front of the wearer'"'"'s head. Fitted over an annular flange around a central aperture of the insert is a harness attachment. Because the insert and harness attachment can be lightweight, the mask can be lighter in weight than are prior masks having filters of equal weight. The novel respiratory mask can be of low cost, thus making it economical to be discarded after each use.

Claims

1. A structural member for use in a facepiece of a respiratory mask, said structural member being thin and rigid relative to the facepiece and having a pair of substantially flat, swept back cheek portions, each formed with an aperture and structure around the aperture to mate with and hold a filter cartridge, and a central portion having a nose aperture for an exhalation valve, and provided with discontinuities permitting the facepiece material to flow through the discontinuities under molding conditions to form a mechanical seal to the structural member.

2. A structural member as defined in claim 1 wherein said discontinuities are provided by a series of closely spaced perforations extending through the structural member.

3. A respirator mask comprising a soft, compliant facepiece adapted to mate with the wearer'"'"'s face, a polymeric insert, and at least one filter holder;

wherein the insert is thin and rigid relative to the facepiece, functions as a supporting frame to the mask and has at least one aperture and structure around the aperture to mate with and hold said filter holder; and

wherein the facepiece is molded in sealing engagement around the insert, the facepiece material having contacted the insert while in a liquid state so as to have flowed into contact with the insert thereby forming a permanent seal to the insert upon solidifying.

4. A respiratory mask according to claim 3 wherein the insert is provided with discontinuities permitting the facepiece material, while in a liquid state, to flow through the discontinuities thereby forming a permanent seal to the insert upon solidifying.

5. A respiratory mask according to claim 4 wherein the discontinuities are provided by a series of closely spaced perforations extending through the insert.

6. A respirator mask according to claim 3 wherein the facepiece adjacent said aperture has a radially sloped ridge with a substantially feathered edge that is bent outwardly and stretched by an attached filter holder to ensure a hermetical seal.

7. A respirator mask according to claim 3 wherein the structure around each aperture is formed to permit a filter holder to be snapped into place.

8. A respirator mask according to claim 3 wherein the edge of each aperture is formed with at least one notch into which a locking tab projecting from a filter holder fits to prevent a filter holder from rotating.

9. A respirator mask according to claim 4 wherein the mask has to filter holders, and the insert has a central portion and two swept back cheek portions extending from the central portion, each swept back cheek portion having an aperture and structure around the aperture to mate with and hold a filter holder.

10. A respirator mask according to claim 9 wherein the central portion of the insert includes an area that extends upwardly from a line extending between the apertures in the swept back cheek portions so as to extend over the nose of the person wearing the mask.

11. A respirator mask according to claim 10 wherein the central portion of the insert has an aperture for receiving an exhalation valve.

12. A respirator mask comprising a soft compliant facepiece adapted to mate with a wearer'"'"'s face and including an insert for use in said facepiece of said respirator mask, said insert being thin and rigid relative to the facepiece and having a pair of substantially flat, swept back cheek portions, each formed with an aperture and structure around the aperture to mate with and hold a filter cartridge and a central portion having a nose aperture for an exhalation valve, and means for providing a mechanical interlock between the insert and the facepiece, said means including a plurality of discontinuities, said facepiece being made from a material which flows through said discontinuities under molding conditions, said facepiece being secured to said insert by material which has flowed though said discontinuities.

13. Respirator mask as defined in claim 12 wherein the discontinuities are provided by a series of closely spaced perforations extending through the insert.

14. A respirator mask of claim 12 wherein the edge of each aperture is formed with at least one notch into which a locking tab projecting from a filter cartridge fits to prevent a filter cartridge from rotating.

15. A respirator mask of claim 12 wherein the mask has two filter cartridges.

16. A respirator mask as defined in claim 15 wherein each filter cartridge comprises an asymmetric filter cartridge locked to the facepiece, each swept back laterally from a cheek aperture of the insert.

17. A respirator mask of claim 15 in which the central portion of the insert extends upwardly from a line extending between the apertures in the swept back cheek portions so as to extend over the nose of a person wearing the mask.

18. Respirator mask as defined in claim 17 wherein the insert is formed adjacent the nose aperture to receive a harness attachment.

19. Respirator mask as defined in claim 12 wherein each substantially flat swept back cheek portion is swept back at substantially the same angle of from 20°

to 70°

with the plane of symmetry of the mask.

20. A respirator mask of claim 12 wherein the facepiece adjacent each of said cheek apertures has a radially sloped ridge with a substantially feathered edge that is bent outwardly and stretched by an attached filter cartridge to ensure a hermetical seal.

21. A respirator mask of claim 12 wherein the structure around each cheek aperture is formed to permit a filter cartridge to be snapped into place.