Exhalation and inhalation valves that have a multi-layered flexible flap

• US 7,013,895 B2
• Filed: 01/21/2005
• Issued: 03/21/2006
• Est. Priority Date: 11/21/2001
• Status: Expired due to Term

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Martin, Philip G., Xue, Jianxian
• Primary Examiner(s): MITCHELL, TEENA KAY
• Application Number:
  US11/041,044
• Publication Number:
  US 20050155607A1
• Time in Patent Office: 424 Days
• Field of Search: 128/203.11, 128/201.28, 128/205.24, 128/206.15, 128/205.25, 128/206.21, 128/206.28, 128/207.12, 128/207.16, 137/855, 137/856, 137/857, 137/858
• US Class Current: 128/205.24
• CPC Class Codes: A62B 18/10 Valves

Abstract

Exhalation and inhalation valves that are sized and adapted to fit on a mask body of a personal respiratory protection device. The exhalation and inhalation valves comprise a valve seat that has a seal surface and an orifice through which an exhale flow stream may pass to leave the interior gas space. A flexible flap is mounted to the valve seat such that the flap makes contact with the seal surface when the valve is in its closed position and such that the flap can flex away from the seal surface during an exhalation to allow exhaled air to pass through the orifice to ultimately enter an exterior gas space. The flexible flap has at least first and second juxtaposed layers where at least one of the layers is stiffer or has a different elastic modulus than the other layer. These valves provide extraordinarily lower pressure drop in use, and they operate more efficiently and require less actuation power to operate. The end user therefore derives greater comfort when wearing a respiratory mask that uses the inventive valve.

Claims

1. An exhalation valve that comprises:

(i) valve seat that is sized and adapted for securement to a personal respiratory mask and that comprises a seal surface and an orifice through which a fluid may pass; and

(ii) a flexible flap that is mounted to the valve seat such that the flap makes contact with the seal surface when the valve is in its closed position and such that the flap can flex away from the seal surface when an exhale flow stream is passing through the valve, the flexible flap comprising at least first and second juxtaposed layers, wherein at least one of the layers is stiffer or has a greater modulus of elasticity than the other.

2. The exhalation valve of claim 1, wherein the first layer is disposed closer to the seal surface than the second layer when the valve is closed, and wherein the second layer has a greater modulus of elasticity than the first layer.

3. The exhalation valve of claim 2, wherein the first layer contacts the seal surface when the flap is positioned against the seal surface.

4. The exhalation valve of claim 2, wherein the flexible flap has a thickness of about 10 to 2,000 μ

m.

5. The exhalation valve of claim 2, wherein the flexible flap has a thickness of about 20 to 700 μ

m.

6. The exhalation valve of claim 2, wherein the flexible flap has a thickness of about 25 to 600 μ

m.

7. The exhalation valve of claim 2, wherein the first layer has a thickness of about 5 to 700 μ

m, and wherein the second layer has a thickness of about 5 to 100 μ

m.

8. The exhalation valve of claim 2, wherein the first layer has a thickness of about 10 to 600 μ

m, and wherein the second layer has a thickness of about 10 to 85 μ

m.

9. The exhalation valve of claim 2, wherein the first layer has a thickness of about 12 to 500 μ

m, and wherein the second layer has a thickness of about 15 to 75 μ

m.

10. The exhalation valve of claim 2, wherein a pressure drop across the valve at a flow rate of 85 liters per minute is less than about 50 Pascals.

11. The exhalation valve of claim 2, wherein a pressure drop across the valve at a flow rate of 85 liters per minute is less than about 40 Pascals.

12. The exhalation valve of claim 2, wherein a pressure drop across the valve at a flow rate of 85 liters per minute is less than about 30 Pascals.

13. The exhalation valve of claim 2, wherein a pressure drop across the valve at a flow rate of 10 liters per minute is less than 30 Pascals.

14. The exhalation valve of claim 2, wherein a pressure drop across the valve at a flow rate of 10 liters per minute is less than 30 Pascals.

15. The exhalation valve of claim 2, wherein a pressure drop across the valve at a flow rate of 10 liters per minute is less than 25 Pascals.

16. The exhalation valve of claim 2, wherein a pressure drop across the valve at a flow rate of 10 liters per minute is less than 20 Pascals.

17. The exhalation valve of claim 2, wherein a pressure drop across the valve is about 5 to 50 Pascals between flow rates of 10 liters per minute and 85 liters per minute.

18. The exhalation valve of claim 2, wherein a pressure drop across the valve is about 5 to 25 Pascals between flow rates of 10 liters per minute and 85 liters per minute.

19. The exhalation valve of claim 2 wherein the pressure drop is less than 5 Pascals at flow rates of 10 liters per minute.

20. The exhalation valve of claim 2, wherein the first layer contains a rubber, and wherein the second layer contains polyethylene terephthalate or polycarbonate.

21. The exhalation valve of claim 20, wherein rubber is a styrene-butadiene-styrene block copolymer.

22. The exhalation valve of claim 1, being a button-style valve.

23. The exhalation valve of claim 1, wherein the exhalation valve is a flapper-style exhalation valve.

24. The exhalation valve of claim 23, wherein the flapper-style exhalation valve has a planar seal surface.

25. The exhalation valve of claim 24, wherein the flexible flap is not pressed against the seal surface under neutral conditions.

26. The exhalation valve of claim 1, wherein the flexible flap includes a third layer that has substantially the same stiffness as the first layer.

27. The exhalation valve of claim 26, wherein the flexible flap exhibits symmetry with respect to the second layer, and wherein the second layer is stiffer than the first and third layers.

28. The exhalation valve of claim 1, wherein the second layer has a modulus of elasticity that is greater than the first layer, and wherein the first layer contacts the seal surface when the flap is positioned against the seal surface.

29. The exhalation valve of claim 28, wherein the modulus of elasticity of the first layer is about 0.15 to 10 megaPascals, and wherein the modulus of elasticity of the second layer is about 2 to 1.1×

10⁶ megaPascals.

30. The exhalation valve of claim 28, wherein the modulus of elasticity of the first layer is preferably about 1 to 7 megaPascals, and wherein the modulus of elasticity of the second layer is about 200 to 11,000 megaPascals.

31. The exhalation valve of claim 30, wherein the second layer has a modulus of elasticity of 300 to 5000 megaPascals.

32. The exhalation valve of claim 1, wherein the second layer is stiffer than the first layer, and wherein the moduli ratio between the first layer and the second layer is less than 1.

33. The exhalation valve of claim 1, wherein the second layer is stiffer than the first layer, and wherein the moduli ratio between the first layer and the second layer is less than 0.01.

34. The exhalation valve of claim 1, wherein the second layer is stiffer than the first layer, and wherein the moduli ratio between the first layer and the second layer is less than 0.001.

35. The exhalation valve of claim 1, wherein the exhalation valve includes a third layer such that the flap has an ABA construction, wherein the B layer is stiffer than the A layers.

36. The exhalation valve of claim 1, wherein the exhalation valve includes a third layer such that the flap has an ABA′

construction, wherein the B layer is stiffer than the A and A′

layers, and wherein the A layer is located closer to the seal surface than the B layer.

37. The exhalation valve of claim 1, wherein the exhalation valve includes a third layer such that the flap has an ABC construction, wherein the B layer is stiffer than the A layers, and wherein the A layer is located closer to the seal surface than the B layer.

38. The exhalation valve of claim 1, wherein the exhalation valve includes a third layer such that the flap has an ABC construction, wherein the C layer is stiffer than the A and B layers, and is located closer to the seal surface than the A and B layers.

39. The exhalation valve of claim 1, wherein the first and second layers both contain polymer materials.

40. The exhalation valve of claim 1, wherein the exhalation valve exhibits a valve efficiency of about 2 to 20 mW·

g cm³/min.

41. The exhalation valve of claim 1, wherein the exhalation valve exhibits a valve efficiency of about 2 to 10 mW·

g cm³/min.

42. An inhalation valve that comprises:

(i) valve seat that is sized and adapted for sceurement to a personal respiratory mask and that comprises a seal surface and an orifice through which a fluid may pass; and

(ii) a flexible flap that is mounted to the valve seat such that the flap makes contact with the seal surface when the valve is in its closed position and such that the flap can flex away from the seal surface when an inhale flow stream is passing through the valve, the flexible flap comprising at least first and second juxtaposed layers, wherein at least one of the layers is stiffer or has a greater modulus of elasticity than the other.

43. The inhalation valve of claim 42, wherein the first layer is disposed closer to the seal surface than the second layer when the valve is closed, and wherein the second layer is stiffer than the first layer.

44. The inhalation valve of claim 42, being in the form of a button-style valve.