System for vehicle emission sampling and measurement

• US 6,516,656 B1
• Filed: 12/28/1999
• Issued: 02/11/2003
• Est. Priority Date: 12/28/1999
• Status: Expired due to Fees

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Inventors: Yamazaki, Kazumi, Jetter, Jeffrey Jay, Maeshiro, Shinji
• Primary Examiner(s): OEN, WILLIAM L
• Application Number:
  US09/473,312
• Time in Patent Office: 1,141 Days
• Field of Search: 73/23.31,23.32,31.05,31.06,116,117.2,117.3,118.1
• US Class Current: 73/114.71
• CPC Class Codes: G01M 15/102 by monitoring exhaust gases

Abstract

An improved emission sampling and measurement system is provided for continuously sampling and analyzing the chemical content of a vehicle emissions and the ambient air for data evaluation and comparison. The emission sampling and measurement system comprises a vehicle having an emissions source, devices for intaking vehicle emissions and ambient air, and analysis devices for determining the chemical content of the emissions and ambient air. The gas streams may be dried in a series of selectively permeable drying tubes prior to measurement in the analysis devices, in order to effectuate a more precise sample of the constituent elements of the gases. Following analysis, the data collected is processed, stored, and compared, and the results displayed on a screen in the vehicle driver'"'"'s compartment in a real-time manner. In this fashion, real-time comparative data analysis is presented in a format not presently available.

Claims

1. An emissions measurement system for a vehicle having an emissions source, comprising:

a first intake coupled to said emission source to collect vehicle emission gases therefrom;

a second intake coupled to a portion of said vehicle spaced from said emission source to collect ambient air;

a first analyzer disposed in said vehicle and coupled to said first intake, said first analyzer providing a first electrical signal corresponding to chemical content of said vehicle emission gases;

a second analyzer disposed in said vehicle and coupled to said second intake, said second analyzer providing a second electrical signal corresponding to chemical content of said ambient air; and

a processor coupled to said first and second analyzers, said processor being adapted to process said first and second electrical signals and provide data corresponding to a comparison of said vehicle emission gases to said ambient air.

2. The emissions measurement system defined in claim 1, further comprising a dryer for removing moisture from the gas streams.

3. The emissions measurement system defined in claim 2, wherein said dryer further comprises;

a plurality of drying tubes coupled together in series, each one of said plurality of drying tubes further having a first flow path for sample gas and a second flow path for purge gas, said sample gas stream passing through said first flow path of each one of said plurality of drying tubes in series;

a cooling chamber having an interior volume maintained at a reduced temperature relative to an ambient temperature of said sample gas stream, at least one of said plurality of drying tubes being disposed in said cooling chamber; and

a purge air source providing a supply of dried air, said purge air source being coupled to said plurality of drying tubes such that dried air passes through said second flow path of each one of said plurality of drying tubes in series;

wherein, said cooling chamber reduces temperature of said sample gas stream below its dew point to increase drying efficiency of said plurality of drying tubes.

4. The emissions measurement system defined in claim 3, wherein each of said plurality of drying tubes comprises an ion exchange polymer material exhibiting a selectively high permeability to transfer of water compared to other gaseous compositions.

5. The emissions measurement system defined in claim 3, wherein said plurality of drying tubes each comprise an outer shell having a sample gas inlet and a sample gas outlet, a plurality of internal tubes comprised of said ion exchange polymer material are disposed within said outer shell extending between said sample gas inlet and said sample gas outlet.

6. The emissions measurement system defined in claim 3, wherein said plurality of drying tubes each comprise a purge gas inlet and a purge gas outlet, whereby water contained in said sample gas flow passes through sides of said internal tubes and is removed through said purge gas outlet.

7. The emissions measurement system defined in claim 3, wherein the cooling chamber further comprises an ice bath.

8. The emissions measurement system defined in claim 3, further comprising a heater coupled to at least one of said plurality of drying tubes prior to said cooling chamber, said heater being adapted to increase temperature of said sample gas stream above said ambient temperature to maintain water contained in said sample gas stream in a vapor state.

9. The emissions measurement system defined in claim 3, wherein said purge air source further comprises at least one tube containing a desiccant material.

10. The emissions measurement system defined in claim 3, further comprising a vacuum pump coupled to said plurality of drying tubes and adapted to draw said sample gas flow therethrough.

11. The emissions measurement system defined in claim 3, further comprising a fan coupled to the cooling chamber to provide a source of cooled air.

12. The emissions measurement system defined in claim 3, wherein said plurality of drying tubes further comprises three drying tubes.

13. The emissions measurement system defined in claim 3, further comprising a plurality of secondary drying tubes coupled together in series, each one of said plurality of secondary drying tubes further having a first flow path for a secondary sample gas stream and a second flow path for a secondary purge gas, said secondary sample gas stream passing through said first flow path of each one of said plurality of secondary drying tubes in series.

14. The emissions measurement system defined in claim 13, wherein at least one of said plurality of secondary drying tubes are disposed in said cooling chamber.

15. The emissions measurement system defined in claim 1, further comprising a device for removing water from said sample gas stream, said apparatus comprising:

first means for drying said sample gas stream at a temperature above an ambient temperature; and

second means for drying said sample gas stream at a temperature below said ambient temperature.

16. The emissions measurement system defined in claim 15, wherein said first drying means further comprises at least one drying tube having a first flow path for sample gas and a second flow path for purge gas, and a heater coupled to said at least one drying tube, said heater being adapted to increase temperature of said sample gas stream above said ambient temperature to maintain water contained in said sample gas stream in a vapor state.

17. The emissions measurement system defined in claim 15, wherein said second drying means further comprises a cooling chamber having an interior volume maintained at a reduced temperature relative to said ambient temperature of said sample gas stream, at least one drying tube being disposed in said cooling chamber, said cooling chamber reducing temperature of said sample gas stream below its corresponding dew point to thereby increase drying efficiency of said at least one drying tube contained therein.

18. The emissions measurement system defined in claim 17, wherein said at least one drying tube of each of said first and second drying means each comprises an ion exchange polymer material exhibiting a selectively high permeability to transfer of water compared to other gaseous compositions.

19. The emissions measurement system defined in claim 17 wherein said at least one drying tube of each of said first and second drying means each comprises an outer shell having a sample gas inlet and a sample gas outlet, a plurality of internal tubes comprised of said ion exchange polymer material are disposed within said outer shell extending between said sample gas inlet and said sample gas outlet.

20. The emissions measurement system defined in claim 19, wherein said at least one drying tube of each of said first and second drying means each comprises a purge gas inlet and a purge gas outlet, whereby water contained in said sample gas flow passes through sides of said internal tubes and is removed through said purge gas outlet.

21. The emissions measurement system defined in claim 17, wherein the cooling chamber further comprises an ice bath.

22. The emissions measurement system defined in claim 15, further comprising a purge air source providing a supply of dried air to said first and second drying means.

23. The emissions measurement system defined in claim 22, wherein said purge air source further comprises at least one tube containing a desiccant material.

24. The emissions measurement system defined in claim 15, wherein said second drying means further comprising means for drying a secondary sample gas stream.

25. The emissions measurement system defined in claim 1, wherein said first analyzer and said second analyzer comprise a first and a second Fourier transformer infrared gas analysis spectrometer, respectively.

26. The emissions measurement system defined in claim 25, wherein each of said first and said second Fourier transformer infrared gas analysis spectrometers further comprise:

an infrared radiation source;

a resonant cavity adapted to contain a gas sample, said infrared radiation source being conducted into said resonant cavity.

27. The emissions measurement system defined in claim 1, further comprising a display device wherein the data corresponding to said vehicle emissions and said ambient air may be displayed, said display device connected to said processor.

28. The emissions measurement system defined in claim 27 wherein said display device further comprises an interactive screen wherein said interactive screen produces electrical signals when touched and sends said electrical signals to said processor.

29. The emissions measurement system defined in claim 1, where a vacuum pump is utilized to draw the exhaust gas through the pollution measuring apparatus.

30. A method of measuring constituent components in vehicle exhaust gases, comprising the steps of:

collecting a sample of vehicle exhaust gases from an emission system of a vehicle;

collecting a sample of ambient air;

analyzing said vehicle exhaust gas sample and determining said constituent components of said vehicle exhaust gas sample

analyzing said ambient air sample and determining constituent components of said ambient air sample; and

comparing said determined chemical content of said vehicle emission gases and said ambient air.

31. The method of claim 30, further comprising the step of removing moisture from said vehicle exhaust gas and said ambient air sample.

32. The method of claim 31, wherein said step of removing moisture further comprises a method of cooling said gases to an approximate dew point.

33. The method of claim 30, wherein each of said analyzing steps further comprises conducting Fourier transformer infrared gas analysis.

34. The method of claim 30, further comprising the step of displaying said constituent components of said vehicle exhaust gas and said constituent components of said ambient air.

35. The method of claim 30, further comprising the step of specifying at least one of said constituent components of said vehicle exhaust gas sample and said ambient air sample to be displayed, scale and range of axes of said display, a degree of data smoothing, and an error detection threshold.

36. The method of claim 30, further comprising the step of selecting one of a strip-chart and an oscilloscope mode.

37. The method of claim 30, further comprising the step of specifying one of a real-time and a playback mode.

38. The method of claim 30, further comprising the step of retrieving data corresponding to said constituent components of said vehicle emissions gases and said ambient air.

39. The method of claim 30, further comprising the step of displaying a chart of said constituent components versus time.

40. The method of claim 30, further comprising the step of comparing a level of said constituent components of said vehicle emissions gases to a level of said constituent components of said ambient air.

41. The method of claim 30, further comprising the step of lighting display indicators showing when said constituent components of said vehicle emissions gases reach a level that is less than a corresponding level of constituent components of said ambient air.

42. The method of claim 30, further comprising the step of calculating a percentage of time that said constituent component levels of said ambient air are greater than said constituent component levels of said vehicle emission gases.