Devices and methods for sensing condensation conditions and for preventing and removing condensation from surfaces

• US 6,886,351 B2
• Filed: 08/18/2003
• Issued: 05/03/2005
• Est. Priority Date: 09/18/2001
• Status: Active Grant

• Current Assignee: Integrity Engineering Incorporated
• Original Assignee: Don A. Skomsky, Valerie Palfy
• Inventors: Skomsky, Don A., Palfy, Valerie
• Primary Examiner(s): Jiang, Chen Wen
• Application Number:
  US10/642,267
• Publication Number:
  US 20040050076A1
• Time in Patent Office: 624 Days
• Field of Search: 62/34, 621/40, 621/50, 622/39, 622/72, 150/250.05, 126/271.1, 236/91.C, 219/507, 219/508, 219/509, 219/203, 219/479, 219/494, 165/202, 165/222, 165/223
• US Class Current: 62/140
• CPC Class Codes: A42B 3/245 using means for heating, e.g. electric heating of the visor
• CPC Class Codes: B60H 1/00785 by the detection of humidity or frost
• CPC Class Codes: F24F 11/30 for purposes related to the operation of the system, e.g. for safety or monitoring
• CPC Class Codes: F24F 2013/221 to avoid the formation of condensate, e.g. dew
• CPC Class Codes: F24F 2110/10 Temperature
• CPC Class Codes: F24F 2110/20 Humidity
• CPC Class Codes: F25B 21/02 using Peltier effect; using Nernst-Ettinghausen effect
• CPC Class Codes: F25B 47/006 for preventing frost
• CPC Class Codes: F25D 21/02 Detecting the presence of frost or condensate
• CPC Class Codes: F25D 21/04 Preventing the formation of frost or condensate
• CPC Class Codes: G01N 25/56 by investigating moisture content
• CPC Class Codes: G01N 25/68 by varying the temperature of a condensing surface
• CPC Class Codes: G05D 22/02 characterised by the use of electric means
• CPC Class Codes: G05D 27/02 characterised by the use of electric means
• CPC Class Codes: H05B 1/0236 for vehicles
• CPC Class Codes: H05B 2203/035 Electrical circuits used in resistive heating apparatus
• CPC Class Codes: H05B 3/84 Heating arrangements specially adapted for transparent or reflecting areas, e.g. for demisting or de-icing windows, mirrors or vehicle windshields

Abstract

A device and method is provided for sensing or predicting when condensation having a given physical state is present or imminent and for suppressing such condensation from a surface, such as a vehicle windscreen, eyewear, goggles, helmet visor, computer monitor screen, window, electronic equipment, etc, by preventing or removing it. A first thermal sensor is in thermally conductive contact with the surface. A second thermal sensor is in an environment separated from the surface. A humidity sensor is in the environment of the second thermal sensor. A circuit causes a condensation suppression mechanism to be activated for preventing or removing condensation having the given physical state from the surface when a temperature sensed by the first thermal sensor, a temperature sensed by the second thermal sensor, and a humidity sensed by the humidity sensor indicate that a condensation condition is either present or imminent and requires prevention or removal at the surface.

Claims

1. A device that determines condensation conditions and suppresses condensation having a given physical state from a surface, comprising:

a first thermal sensor in thermally conductive contact with the surface;

a second thermal sensor in an environment separated from the surface;

a humidity sensor in the environment of the second thermal sensor;

a condensation suppression mechanism configured to suppress condensation having the given physical state from the surface; and

a circuit configured to cause the condensation suppression mechanism to be activated when a temperature sensed by the first thermal sensor, a temperature sensed by the second thermal sensor, and a humidity sensed by the humidity sensor indicate that a condensation condition requires suppression at the surface;

wherein the second thermal sensor is positioned at a sufficient distance from the surface such that a space between the surface and the second thermal sensor precludes thermal transfer between the surface and the second thermal sensor.

2. The device of claim 1 wherein the condensation condition is a presence of condensation on the surface, and the condensation suppression mechanism is a condensation removal mechanism configured to remove condensation having the given physical state from the surface the device.

3. The device of claim 1 wherein the given physical state is a liquid state.

4. The device of claim 1 wherein the surface is a windscreen.

5. The device of claim 4 wherein the surface is a windscreen of a vehicle.

6. The device of claim 1 wherein the surface is a helmet visor.

7. The device of claim 1 wherein the surface is a computer monitor screen.

8. The device of claim 1 wherein the surface is a window.

9. The device of claim 1 wherein the surface is an enclosure for electronic equipment.

10. The device of claim 1 wherein the first and second thermal sensors are thermocouples.

11. The device of claim 1 wherein the first thermal sensor is in actual physical contact with the surface.

12. The device of claim 1 wherein the first thermal sensor is affixed to the surface.

13. The device of claim 1 wherein the first thermal sensor is embedded within the surface.

14. The device of claim 1 wherein the humidity sensor is a capacitive sensor.

15. The device of claim 1 wherein the condensation suppression mechanism comprises a fan.

16. The device of claim 1 wherein the condensation suppression mechanism comprises a heating mechanism.

17. The device of claim 1 wherein the condensation suppression mechanism comprises a mechanism configured to divert an airstream through a duct having a heating mechanism contained therein.

18. The device of claim 1 wherein the condensation suppression mechanism comprises an infrared source.

19. The device of claim 1 wherein the circuit configured to cause the condensation suppression mechanism to be activated is configured to directly activate the condensation suppression mechanism.

20. The device of claim 1 wherein the circuit determines that the condensation condition requires suppression at the surface by determining, from the temperature sensed by the second thermal sensor and the humidity sensed by the humidity sensor, the pressure of steam in the environment of the second thermal sensor.

21. The device of claim 20 wherein the circuit determines that the condensation condition requires suppression at the surface by determining a ratio of the pressure of steam in the environment of the second thermal sensor to the saturated steam pressure at the temperature sensed by the first thermal sensor.

22. The device of claim 20 wherein the circuit determines that the condensation condition requires suppression at the surface by determining a difference between a temperature sensed by the first thermal sensor and a dew point temperature associated with the pressure of steam in the environment of the second thermal sensor.

23. The device of claim 1 wherein the condensation condition is a near presence of condensation on the surface, and the condensation suppression mechanism is a condensation preclusion mechanism configured to preclude condensation having the given physical state from the surface the device.

24. The device of claim 1 wherein the surface is an eyewear surface.

25. The device of claim 24 wherein the eyewear surface comprises goggles.

26. The device of claim 25 wherein the goggles are underwater goggles.

27. The device of claim 1 wherein the surface is a respirator mask surface.

28. The device of claim 1 wherein the surface is an optical equipment surface.

29. The device of claim 1 wherein the surface is an electronic circuitry surface.

30. The device of claim 1 wherein at least one of the first and second thermal sensors is a negative temperature coefficient thermistor.

31. The device of claim 1 wherein the condensation suppression mechanism comprises a thermoelectric cooler having a cold side that causes moisture in an airstream to be condensed into liquid water and a hot side that subsequently re-heats the airstream.

32. A method of determining condensation conditions and suppressing condensation having a given physical state from a surface having a first thermal sensor in thermally conductive contact therewith, comprising:

sensing a temperature using the first thermal sensor;

sensing a temperature using a second thermal sensor in an environment separated from the surface;

sensing humidity using a humidity sensor in the environment of the second thermal sensor;

causing a condensation suppression mechanism to be activated in order to suppress condensation having the given physical state from the surface when the temperature sensed by the first thermal sensor, the temperature sensed by the second thermal sensor, and the humidity sensed by the humidity sensor indicate that a condensation condition requires suppression at the surface;

wherein the second thernmal sensor is positioned at a sufficient distance from the surface such that a space between the surface and the second thermal sensor precludes thermal transfer between the surface and the second thermal sensor.

33. The method of claim 32 wherein the step of causing the condensation suppression mechanism to be activated comprises determining that the condensation condition requires suppression at the surface by determining, from the temperature sensed by the second thermal sensor and the humidity sensed by the humidity sensor, the pressure of steam in the environment of the second thermal sensor.

34. The method of claim 33 wherein the step of determining that the condensation condition requires suppression at the surface comprises determining a ratio of the pressure of steam in the environment of the second thermal sensor to the saturated steam pressure at the temperature sensed by the first thermal sensor.

35. The method of claim 33 wherein the step of determining that the condensation condition requires suppression at the stirace comprises determining a difference between a temperature sensed by the first thermal sensor and a dew point temperature associated with the pressure of steam in the environment of the second thermal sensor.

36. The method of claim 32 wherein the condensation condition is a presence of condensation on the surface, and the condensation suppression mechanism is a condensation removal mechanism configured to remove condensation having the given physical state from the surface the device.

37. The method of claim 32 wherein the condensation condition is a near presence of condensation on the surface, and the condensation suppression mechanism is a condensation preclusion mechanism configured to preclude condensation having the given physical state from the surface the device.

38. The method of claim 32 wherein the given physical state is a liquid state.

39. The method of claim 32 wherein the surface is a windscreen.

40. The method of claim 32 wherein the surface is an eyewear surface.

41. The method of claim 40 wherein the eyewear surface comprises goggles.

42. The method of claim 41 wherein the goggles are underwater goggles.

43. The method of claim 41 wherein a protective enclosure encloses at least the humidity sensor, the protective enclosure protecting the humidity sensor from exposure to liquid water.

44. The method of claim 43 wherein the protective enclosure further encloses the second thermal sensor and protects the second thermal sensor from exposure to liquid water.

45. The method of claim 32 wherein the humidity sensor is a capacitive sensor.

46. A device that determines condensation conditions and suppresses condensation having a given physical state from a surface, comprising:

a thermal sensor in thermally conductive contact with the surface;

a humidity sensor;

a condensation suppression mechanism configured to suppress condensation having the given physical state from the surface;

a circuit configured to cause the condensation suppression mechanism to be activated when a temperature sensed by the thermal sensor and a humidity sensed by the humidity sensor indicate that a condensation condition requires suppression at the surface; and

a protective enclosure enclosing at least the humidity sensor in close proximity to the humidity sensor, the protective enclosure protecting the humidity sensor from exposure to liquid water.

47. The device of claim 46 wherein the humidity sensor is separated from and distinct from the thermal sensor.

48. The device of claim 46 wherein the humidity sensor is separated from the surface.

49. The device of claim 46 further comprising a second thermal sensor in an environment separated from the surface.

50. The device of claim 49 wherein the humidity sensor is in the environment of the second thermal sensor.

51. The device of claim 49 wherein the protective enclosure further encloses the second thermal sensor and protects the second thermal sensor from exposure to liquid water.

52. The device of claim 46 wherein the protective enclosure is a hydrophobic cover that protects the humidity sensor from exposure to liquid water while permitting transference of gas across its boundary.

53. A method of determining condensation conditions and suppressing condensation having a given physical state from a surface having a thermal sensor in thermally conductive contact therewith, comprising:

sensing a temperature using the thermal sensor;

sensing humidity using a humidity sensor enclosed by a protective enclosure in close proximity to the humidity sensor, the protective enclosure protecting the humidity sensor from exposure to liquid water; and

causing a condensation suppression mechanism to be activated in order to suppress condensation having the given physical state from the surface when the temperature sensed by the thermal sensor and the humidity sensed by the humidity sensor indicate that a condensation condition requires suppression at the surface.

54. A device that determines condensation conditions and suppresses condensation having a given physical state from a surface, comprising:

a first thermal sensor in thermally conductive contact with the surface;

a second thermal sensor in an environment separated from the surface;

a humidity sensor in the environment of the second thermal sensor;

a condensation suppression mechanism configured to suppress condensation having the given physical state from the surface; and

a circuit configured to cause the condensation suppression mechanism to be activated when a temperature sensed by the first thermal sensor, a temperature sensed by the second thermal sensor, and a humidity sensed by the humidity sensor indicate that a condensation condition requires suppression at the surface;

wherein the second thermal sensor is in thermally conductive contact with a temperature-changing device, and further comprising a circuit configured to activate the temperature-changing device in order to maintain the second thermal sensor at a temperature that is different from a temperature of the first thermal sensor, wherein the humidity sensor is in thermally conductive contact with the temperature-changing device.

55. The device of claim 54 wherein the circuit is configured to cause the condensation suppression mechanism to be activated when the humidity sensor indicates a high humidity condition at the temperature that is different from the temperature of the first thermal sensor.

56. A method of determining condensation conditions and suppressing condensation having a given physical state from a surface having a first thermal sensor in thermally conductive contact therewith, comprising:

sensing a temperature using the first thermal sensor;

sensing a temperature using a second thermal sensor in an environment separated from the surface;

sensing humidity using a humidity sensor in the environment of the second thermal sensor;

causing a condensation suppression mechanism to be activated in order to suppress condensation having the given physical state from the surface when the temperature sensed by the first thermal sensor, the temperature sensed by the second thermal sensor, and the humidity sensed by the humidity sensor indicate that a condensation condition requires suppression at the surface;

wherein the second thermal sensor is in thermally conductive contact with a temperature-changing device, the method further comprising activating the temperature-changing device in order to maintain the second thermal sensor at a temperature that is different from a temperature of the first thermal sensor, wherein the humidity sensor is in thermally conductive contact with the temperature-changing device.

57. The method of claim 56 wherein the wherein the step of causing the condensation suppression mechanism to be activated comprises causing the condensation suppression mechanism to be activated when the humidity sensor indicates a high humidity condition at the temperature that is different from the temperature of the first thermal sensor.