Ethyl alcohol sensor and method of use

• US 20040141171A1
• Filed: 01/21/2003
• Published: 07/22/2004
• Est. Priority Date: 01/21/2003
• Status: Active Grant

• Current Assignee: Aptiv Technologies AG (Aptiv PLC)
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Han, Taefyoung, Sultan, Michel F., Lambert, David K., Fisher, Galen Bruce, Myers, Mark E.
• Granted Patent: US 7,095,501 B2
• Time in Patent Office: Days
• US Class Current: 356/36
• CPC Class Codes: B60K 28/063 preventing starting of vehicles
• CPC Class Codes: G01N 1/2214 by sorption
• CPC Class Codes: G01N 1/40 Concentrating samples
• CPC Class Codes: G01N 1/405 by adsorption or absorption
• CPC Class Codes: G01N 33/4972 Determining alcohol content for vehicle safety devices B60K28/06

Abstract

An ethanol sensing unit and a method of using, wherein the unit is particularly suitable for use in a confined environment such as the passenger compartment of a passenger vehicle. The sensing unit comprises a device for collecting ethanol vapors while the device is at a first temperature, a device for heating the collecting device to a second temperature higher than the first temperature so as to release ethanol vapors from the collecting device, and a device for sensing the ethanol vapors released from the collecting device when heated by the heating device. The sensing unit is also adapted to delay the operation of the heating device until a period of time sufficient for the collecting device to adsorb ethanol vapors from air contained in the confined environment.

Claims

1. An ethanol sensing unit comprising:

means for collecting ethanol vapors from an air sample taken from a surrounding environment while the collecting means is at a first temperature;

means for heating the collecting means to a second temperature higher than the first temperature so as to release ethanol vapors from the collecting means;

means for delaying operation of the heating means until a period of time sufficient for the collecting means to collect ethanol vapors from the air sample; and

means for sensing the ethanol vapors released from the collecting means when heated by the heating means.

2. The ethanol sensing unit according to claim 1, wherein the sensing means measures the concentration of ethanol vapors released from the collecting means.

3. The ethanol sensing unit according to claim 1, wherein the collecting means comprises an adsorbent material chosen from the group consisting of carbon molecular sieves, activated carbon materials with a porous graphitic microstructure, porous polymers, and inorganic materials with high surface area.

4. The ethanol sensing unit according to claim 1, wherein the sensing means comprises a metal oxide film on a ceramic substrate.

5. The ethanol sensing unit according to claim 1, wherein the delaying means and the heating means are operative to permit collection of ethanol vapors by the collecting means over a longer period of time than the heating means heats the collecting means to release the ethanol vapors, so that the ethanol vapors released from the collecting means are at a higher concentration than the ethanol vapors within the air sample.

6. The ethanol sensing unit according to claim 1, wherein the collecting means selectively adsorbs ethanol.

7. The ethanol sensing unit according to claim 1, wherein the sensing means selectively senses ethanol.

8. The ethanol sensing unit according to claim 1, further comprising means for flowing the air sample from the surrounding environment over the collecting means.

9. The ethanol sensing unit according to claim 1, wherein the surrounding environment is a passenger compartment of a vehicle.

10. The ethanol sensing unit according to claim 9, wherein the collecting means is located in an exit vent of the passenger compartment.

11. The ethanol sensing unit according to claim 1, wherein the collecting means is configured to be alternatingly subjected to multiple air samples taken from different locations within the surrounding environment, and the sensing means is operable to compare the levels of the ethanol vapors collected from the multiple air samples.

12. A passive ethanol sensing unit located in a passenger compartment of a vehicle, the sensing unit comprising:

an adsorbent material capable of adsorbing ethanol vapors;

means for flowing air from the passenger compartment over the adsorbent material to cause adsorption by the adsorbent material of any ethanol vapors contained in the air while the adsorbent material is at a first temperature;

means for heating the adsorbent material to a second temperature higher than the first temperature so as to release ethanol vapors from the adsorbent material;

means for delaying operation of the heating means until a period of time sufficient for the adsorbent material to adsorb ethanol vapors from the air flowed over the adsorbent material by the flowing means; and

means for measuring the concentration of the ethanol vapors released from the adsorbent material when heated by the heating means.

13. The ethanol sensing unit according to claim 12, wherein the adsorbent material is chosen from the group consisting of carbon molecular sieves, activated carbon materials with a porous graphitic microstructure, porous polymers, and inorganic materials with high surface area.

14. The ethanol sensing unit according to claim 12, wherein the measuring means comprises a metal oxide film on a ceramic substrate.

15. The ethanol sensing unit according to claim 12, wherein the adsorbent material selectively adsorbs ethanol.

16. The ethanol sensing unit according to claim 12, wherein the measuring means selectively senses ethanol.

17. The ethanol sensing unit according to claim 12, wherein the adsorbent material is located in an exit vent of the passenger compartment.

18. A method of sensing ethanol vapors, the method comprising the steps of:

collecting ethanol vapors from an air sample taken from a surrounding environment with a collecting means at a first temperature;

after a period of time sufficient for the collecting means to collect ethanol vapors from the air sample, heating the collecting means to a second temperature higher than the first temperature so as to release ethanol vapors from the collecting means; and

then

sensing ethanol vapors released from the collecting means when heated.

19. The method according to claim 18, wherein the concentration of ethanol vapors released from the collecting means is measured during the sensing step.

20. The method according to claim 18, wherein the collecting means comprises an adsorbent material chosen from the group consisting of carbon molecular sieves, activated carbon materials with a porous graphitic microstructure, porous polymers, and inorganic materials with high surface area.

21. The method according to claim 18, wherein the sensing step is performed with a sensing means comprising a metal oxide film on a ceramic substrate.

22. The method according to claim 18, wherein collection of ethanol vapors by the collecting means occurs over a longer period of time than the heating of the collecting means to release the ethanol vapors, and the ethanol vapors released from the collecting means are at a higher concentration than the ethanol vapors within the air sample.

23. The method according to claim 18, wherein the collecting means selectively adsorbs ethanol.

24. The method according to claim 18, wherein ethanol is selectively sensed during the sensing step.

25. The method according to claim 18, further comprising the step of flowing the air sample from the surrounding environment over the collecting means.

26. The method according to claim 25, further comprising the step of discontinuing the flowing of the air sample from the surrounding environment over the collecting means during the heating and sensing steps.

27. The method according to claim 18, wherein the surrounding environment is a passenger compartment of a vehicle.

28. The method according to claim 27, wherein the collecting means is located in an exit vent of the passenger compartment.

29. The method according to claim 18, wherein the collecting step comprises alternatingly subjecting the collecting means to multiple air samples taken from different locations within the surrounding environment, and the sensing step comprises comparing the levels of the ethanol vapors collected from the multiple air samples.

30. A method of passively sensing ethanol vapors within a passenger compartment of a vehicle, the method comprising the steps of:

flowing air from the passenger compartment over an adsorbent material held at a first temperature so that any ethanol vapors in the air are adsorbed by the adsorbent material;

heating the adsorbent material to a second temperature higher than the first temperature so as to release ethanol vapors from the adsorbent material; and

then

measuring the concentration of the ethanol vapors released from the adsorbent material when heated.

31. The method according to claim 30, wherein the adsorbent material is chosen from the group consisting of carbon molecular sieves, activated carbon materials with a porous graphitic microstructure, porous polymers, and inorganic materials with high surface area.

32. The method according to claim 30, wherein the measuring step is performed with a measuring means comprising a metal oxide film on a ceramic substrate.

33. The method according to claim 30, wherein the adsorbent material selectively adsorbs ethanol.

34. The method according to claim 30, wherein ethanol is selectively sensed during the measuring step.

35. The method according to claim 30, further comprising the step of discontinuing the flowing of air from the passenger compartment over the adsorbent material during the heating and measuring steps.

36. The method according to claim 30, wherein the adsorbent material is located in an exit vent of the passenger compartment.