Clean gas purge for breathing gas regulator

• US 20040000311A1
• Filed: 12/18/2002
• Published: 01/01/2004
• Est. Priority Date: 06/24/2002
• Status: Active Grant

• Current Assignee: Honeywell Safety Products USA, Inc. (Honeywell International Inc.)
• Original Assignee: Surviair Respirators, Inc.
• Inventors: Lowry, Philip L.
• Granted Patent: US 6,966,316 B2
• Time in Patent Office: Days
• US Class Current: 128/204.26
• CPC Class Codes: A62B 9/027 pilot operated, i.e. controlled by valve means sensitive to a reduced downstream pressure
• CPC Class Codes: A62B 9/04 Couplings; Supporting frames
• CPC Class Codes: Y10S 137/908 Respirator control

Abstract

A self contained breathing apparatus (SCBA) served by a source of breathing gas with a mask and a demand regulator connected to the mask. The regulator has a flexible diaphragmatic member having a side exposed to ambient that moves in response to pressure differentials to cause a valve mechanism to introduce breathing gas to the mask. A passage provides breathing gas over said diaphragm exposed to ambient which can be a passage from one side of the diaphragm to the other. A protective cover can overlie the passage which can be displaced upon gas flow through the passage. The method purges ambient contaminants from the diaphragm by providing breathing gas over the diaphragm through an opening of the diaphragm.

Claims

1. A self contained breathing apparatus (SCBA) having a demand regulator comprising:

a source of breathing gas;

a mask with a lens;

a demand regulator connected to said mask and said source of breathing gas;

a flexible member in said demand regulator that moves in response to pressure differentials;

a valve for introducing breathing gas through said regulator to said mask connected for movement in response to movement of said flexible member; and

,

a passage for providing breathing gas over the outside of said flexible member;

2. The SCBA as claimed in claim 1 further comprising:

said flexible member is at least in part formed of an elastomer.

3. The SCBA as claimed in claim 2 further comprising:

said passage is formed as an opening from the inside of said flexible member to the opposite side.

4. The SCBA as claimed in claim 3 further comprising:

a cover overlying said passage which can be displaced upon breathing gas flowing through said passage.

5. The SCBA as claimed in claim 4 further comprising:

said cover is an elastomeric member; and

,

said flexible member is a diaphragm.

6. The SCBA as claimed in claim 3 further comprising:

said flexible member is at least in part a diaphragm; and

,

said regulator when in use maintains a pressure above ambient in said mask and on the inside of said diaphragm.

7. The SCBA as claimed in claim 6 further comprising:

said passage provides flow over the outside of said diaphragm when said regulator is in use; and

,

an outlet is connected to the outside of said diaphragm for allowing flow from said passage to the ambient.

8. The SCBA as claimed in claim 7 further comprising:

a flexible disk like member over said passage that allows flow thereunder when breathing gas flow is provided through said passage.

9. A demand breathing gas regulator comprising:

a regulator body for fluid connection to a user'"'"'s mask and a source of breathing gas;

a flexible member operably connected to a breathing gas demand valve supported by said regulator body said flexible member having one side exposed to ambient through an opening in said regulator body; and

,

a passage for delivery of breathing gas over the face of said flexible member exposed to ambient.

10. The demand breathing gas regulator as claimed in claim 9 further comprising:

said flexible member is at least in part formed of a diaphragm; and

,

said passage is formed through said flexible member.

11. The demand breathing gas regulator as claimed in claim 10 further comprising:

a cover overlying said passage which moves in response to breathing gas flowing through said passage.

12. The demand breathing gas regulator as claimed in claim 9 further comprising:

a pilot valve of said regulator that moves in response to pressure differentials on said flexible member; and

,

a second valve which valves breathing gas through said regulator in response to said pilot valve.

13. The demand breathing gas regulator as claimed in claim 12 further comprising:

a cover overlying said passage formed of an elastomer which is displaced upon flow of breathing gas through said passage.

14. A contaminant purge system for a breathing gas demand regulator comprising:

a demand breathing gas regulator adapted for connection to a source of breathing gas and a user'"'"'s mask;

a flexible member fluidically connected on one side to said source of breathing gas and on the other side to ambient; and

,

a passage connected to said source of breathing gas for delivery of breathing gas to the outside of said flexible member exposed to ambient.

15. The contaminant purge system for a breathing gas demand regulator as claimed in claim 14 wherein:

said passage is formed through said flexible member.

16. The contaminant purge system for a breathing gas demand regulator as claimed in claim 15 wherein:

said flexible member is at least in part a diaphragm.

17. The contaminant purge system for a breathing gas demand regulator as claimed in claim 16 wherein:

said diaphragm is supported at least in part by a member overlying said diaphragm that is stiffer than said diaphragm.

18. The contaminant purge system for a breathing gas demand regulator as claimed in claim 16 further comprising:

said system is connected with a self contained breathing apparatus (SCBA).

19. A self contained breathing apparatus (SCBA) comprising:

a tank for containment of breathing gas;

a first stage regulator fluidically connected to said tank;

a second stage regulator fluidically connected to said first stage regulator;

a mask fluidically connected to said second stage regulator;

a diaphragm in said second stage regulator having an outside portion exposed to ambient with the opposite inside portion of said diaphragm in fluid communication with a user;

a valve operably connected to the diaphragm on the inside of said regulator for providing breathing gas at a pressure above ambient; and

,

a passage through said diaphragm from the inside portion thereof to provide breathing gas on the side of said diaphragm exposed to ambient.

20. The SCBA as claimed in claim 19 further comprising:

said valve operably connected to said diaphragm is a pilot valve fluidically connected to a second valve for causing flow of breathing gas.

21. The SCBA as claimed in claim 19 further comprising:

a cover overlying said passage which allows flow from said passage when breathing gas flows therethrough.

22. The SCBA as claimed in claim 19 wherein:

said diaphragm and said cover are comprised at least in part of an elastomeric material.

23. A method for providing regulated breathing gas through a demand regulator comprising:

providing a source of breathing gas;

regulating said breathing gas to an intermediate pressure by a first stage regulator;

conducting said intermediate pressure gas to a demand regulator;

regulating said intermediate pressure by a demand regulator having a flexible member exposed on one side to ambient and on the other side to breathing gas;

passing said breathing gas over said flexible member exposed to ambient; and

,

allowing said breathing gas to flow from the side of said flexible member exposed to ambient.

24. The method as claimed in claim 23 further comprising:

said flexible member is formed at least in part from an elastomer.

25. The method as claimed in claim 23 further comprising:

said intermediate pressure is regulated by a valve mechanism connected to said flexible member.

26. The method as claimed in claim 25 further comprising:

covering said flexible member at least in part when breathing gas is not passing to the side exposed to ambient.

27. A method of purging ambient contaminants from a demand breathing gas regulator comprising:

providing a demand regulator served by a source of breathing gas, said demand regulator having a flexible member exposed on one side to ambient conditions, and on the other side to the breathing gas; and

,

passing breathing gas to the side of said flexible member exposed to ambient and purging at least in part any contaminants from said flexible member by the flow of said gas.

28. The method as claimed in claim 27 wherein:

said flexible member is at least in part an elastomeric diaphragm.

29. The method as claimed in claim 28 wherein:

said breathing gas is passed through an opening of said diaphragm.

30. The method as claimed in claim 29 further comprising:

covering said opening when breathing gas is not passing therethrough.

31. The method as claimed in claim 30 wherein:

said diaphragm is covered by a disc.