Chemical vapor sensor system and method thereof

• US 8,049,174 B2
• Filed: 10/06/2008
• Issued: 11/01/2011
• Est. Priority Date: 05/05/2008
• Status: Active Grant

• Current Assignee: Aptiv Technologies AG
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Lambert, David K.
• Primary Examiner(s): Kim; Kiho
• Application Number:
  US12/287,103
• Publication Number:
  US 20090272174A1
• Time in Patent Office: 1,121 Days
• Field of Search: 250330-335, 2503361-3362, 2503381-3385, 25033901-33915, 250/340, 2503411-3418, 250342-353, 600/529, 600/532, 600/543, 73/233
• US Class Current: 250/343
• CPC Class Codes: G01N 33/4972 Determining alcohol content for vehicle safety devices B60K28/06

Abstract

A chemical vapor sensor system and method are provided, wherein the system includes an air input device, a light source, a detector, a sample chamber, and a processor. The air input device includes at least a sample input port, a reference input port, and an output port. The light source emits light, and the detector receives at least a portion of the emitted light. The sample chamber is in fluid communication with the output port, wherein the air alternatively enters the air input device from the sample input port and the reference input port and enters the sample chamber. The processor receives an output signal from the detector based upon a detection of at least carbon dioxide and ethanol in the air in the sample chamber, wherein the processor determines a blood alcohol content of a person whose breath was received in the sample input port.

Claims

1. A chemical vapor sensor system comprising:

an air input device that comprises a plurality of ports comprising;

a sample input port;

a reference input port; and

an output port;

a light source that emits light;

a detector in optical communication with said light source that receives at least a portion of said light emitted from said light source;

a sample chamber in optical communication between said light source and said detector, and in fluid communication with said output port, wherein a actuator coupled to said sample input port and said reference input port operates such that said air alternatively enters said air input device from said sample input port and said reference input port, and enters said sample chamber, whereby alternating samples from the sample input port and the reference input port are present between the light source and the detector; and

a processor that receives an output signal from said detector based upon a detection of at least carbon dioxide and ethanol in said air in said sample chamber, wherein said processor determines a blood alcohol content (BAC) of a person whose breath was received in said sample input port based on detecting oscillations of the output signal arising from the alternating samples from the sample input port and the reference input port indicating a portion of air from the sample input port that is exhaled breath.

2. The system of claim 1, wherein said detector is a dual element infrared (IR) detector.

3. The system of claim 2, wherein said dual element IR detector comprises:

a first IR filter adapted to transmit a band of IR absorbed by carbon dioxide; and

a second IR filter adapted to transmit a band of IR absorbed by ethanol vapor.

4. The system of claim 1, wherein a chemical vapor sensor is used with a motor vehicle.

5. The system of claim 1, wherein said BAC is determined by determining a ratio of measured ethanol vapors and carbon dioxide in said person'"'"'s breath.

6. The system of claim 1, wherein said output signal communicated from said detector varies as a substantially linear function of an intensity of said light emitted from said light source.

7. The system of claim 1, wherein said BAC of said person'"'"'s breath is determined without said person physically contacting said sample input port.

8. A chemical vapor sensor system comprising:

an air input device that comprises a plurality of ports comprising;

a sample input port;

a reference input port; and

an output port;

an infrared (IR) light source that emits IR light;

a dual element IR detector in optical communication with said IR light source that receives at least a portion of said IR light emitted from said IR light source;

a sample chamber in optical communication between said IR light source and said detector, and in fluid communication with said output port, wherein a actuator coupled to said sample input port and said reference input port operates such that said air alternatively enters said air input device from said sample input port and said reference input port, and enters said sample chamber, whereby alternating samples from the sample input port and the reference input port are present between the light source and the detector; and

a processor that receives an output signal from said dual element IR detector based upon a detection of carbon dioxide and ethanol in said air in said sample chamber, wherein said processor determines a blood alcohol content (BAC) of a person whose breath was received in said sample input port based on detecting oscillations of the output signal arising from the alternating samples from the sample input port and the reference input port indicating a portion of air from the sample input port that is exhaled breath.

9. The system of claim 8, wherein said dual element IR detector comprises:

a first IR filter adapted to transmit a band of IR absorbed by carbon dioxide; and

a second IR filter adapted to transmit a band of IR absorbed by ethanol vapor.

10. The system of claim 8, wherein said BAC is determined by determining a ratio of measured ethanol vapors and carbon dioxide in said person'"'"'s breath.

11. The system of claim 8, wherein said output signal communicated from said detector varies as a substantially linear function of an intensity of said light emitted from said light source.

12. The system of claim 8, wherein said BAC of said person'"'"'s breath is determined without said person physically contacting said sample input port.

13. The system of claim 8 further comprising at least one heater to heat an operating temperature of a chemical vapor sensor above a dew point temperature.

14. A method of detecting chemical vapors, said method comprising the steps of:

alternating air samples between a sample chamber and a reference input that are inputted into a sample chamber;

illuminating a light source;

detecting at least a portion of said light emitted from said light source with a detector, wherein said sample chamber is in optical communication between said light source and said detector;

communicating an output from said detector based upon detection of carbon dioxide and ethanol in said air sample; and

determining a blood alcohol content (BAC) of a person whose breath was received in said sample chamber, wherein said BAC is based based on detecting oscillations of the output signal arising from the alternating samples from the sample input port and the reference input port indicating a portion of air from the sample input port that is exhaled breath.

15. The method of claim 14, wherein said step of determining said BAC further comprises determining a ratio of measured ethanol vapors and carbon dioxide in said person'"'"'s breath.

16. The method of claim 14, wherein said step of determining said BAC further comprises receiving said person'"'"'s breath without said person physically contacting a sample input port.

17. The method of claim 14, wherein said step of detecting said emitted light further comprises transmitting a band of IR absorbed by carbon dioxide and transmitting a band of IR absorbed by ethanol vapor.