Pressure sensor

• US 7,409,863 B2
• Filed: 10/05/2005
• Issued: 08/12/2008
• Est. Priority Date: 10/05/2004
• Status: Expired due to Fees

• Current Assignee: Sensata Technologies Incorporated (Sensata Technologies Holding Plc)
• Original Assignee: Sensata Technologies Maryland Incorporated (Sensata Technologies Holding Plc)
• Inventors: Bullock, Todd M., Bateman, David E., Engle, Robert Eugene
• Primary Examiner(s): NOORI, MAX H
• Application Number:
  US11/244,318
• Publication Number:
  US 20060072868A1
• Time in Patent Office: 1,042 Days
• Field of Search: 737/05
• US Class Current: 73/705
• CPC Class Codes: G01F 23/14 by measurement of pressure
• CPC Class Codes: G01L 9/0076 using photoelectric means
• CPC Class Codes: G01L 9/0077 for measuring reflected light

Abstract

A pressure sensor includes an optical transmitter transmitting a dispersive light toward two optical receivers, all carried in a housing. Pressure changes on the housing cause the light beam to be deflected with the amount of deflection measured by the difference in light received by each of the two receivers. A processor operable with the receivers provides a pressure measurement responsive to the light beam deflection.

Claims

1. A pressure sensor comprising:

a housing;

an optical transmitter carried by the housing, the optical transmitter operable for emitting light;

at least two optical receivers carried by the housing for receiving light emitted from the optical transmitter;

a light beam modifier carried by the housing and responsive to pressure changes thereon for modifying the light received by each of the at least two optical receivers, wherein the light beam modifier comprises a barrier positioned in an optical path of the light beam, the barrier having a light transmitting portion therein for allowing a portion of the light emitted from the optical transmitter to be received by each of the at least two optical receivers, wherein the barrier is movably responsive to the pressure changes on the housing for movement of the light transmission portion, and thus an amount of light received by each of the at least two optical receivers; and

a processor operable for receiving an output signal from each of the optical receivers and providing a pressure measurement responsive to the light modifying.

2. A pressure sensor according to claim 1, wherein the light beam modifier comprises:

a housing wall portion movably responsive to pressure changes thereon; and

a light reflective surface operable with an inside surface of the housing wall portion within the housing,

wherein the light beam emitted from the optical transmitter is directed toward the light reflective surface for an angular reflection therefrom as a reflected light beam directed toward the at least two optical receivers, and

wherein movement of the wall portion results in a change in the angular reflection of the light beam and the modifying of the light received by each of the at least two optical receivers.

3. A pressure sensor according to claim 2, wherein the wall portion movably responsive to the pressure change comprises a diaphragm.

4. A pressure sensor according to claim 2, further comprising a reflector carried on the inside surface, the reflector having the light reflective surface thereon.

5. A pressure sensor according to claim 2, further comprising a beam splitter positioned for receiving the reflected light beam and directing one portion to a first receiver of the at least two optical receivers and a second portion to a second receiver thereof.

6. A pressure sensor according to claim 1, wherein the light transmitting portion includes an aperture.

7. A pressure sensor according to claim 1, wherein the light transmitting portion comprises a transparent portion and at least one of a semitransparent portion and an opaque portion.

8. A pressure sensor according to claim 1, wherein the wall portion movably responsive to the pressure change comprises a diaphragm.

9. A pressure sensor according to claim 1, further comprising a beam splitter positioned for receiving the emitted light beam and directing one portion to a first receiver of the at least two optical receivers and a second portion to a second receiver thereof.

10. A pressure sensor comprising:

a housing;

an optical transmitter carried by the housing, the optical transmitter operable for emitting light;

at least two optical receivers carried by the housing for receiving light emitted from the optical transmitter;

a light beam modifier carried by the housing and responsive to pressure changes thereon for modifying the light received by each of the at least two optical receivers,

wherein the optical transmitter comprises a light emitting diode (LED), and wherein the light beam includes a diverging light beam definable in an intensity spectrum, and wherein a peak intensity of the divergent light beam is measured at a location between the at least two optical receivers, and wherein the pressure changes on the housing result in a movement of the peak intensity toward one of the at least two optical receivers with a negative pressure change on the housing and toward a second of the at least two optical receivers with a positive pressure change on the housing; and

a processor operable for receiving an output signal from each of the optical receivers and providing a pressure measurement responsive to the light modifying.

11. A pressure sensor according to claim 10, wherein the diverging light beam is defined in the intensity spectrum as having a range of divergence angles.

12. A pressure sensor comprising:

a housing;

an optical transmitter carried by the housing, the optical transmitter operable for emitting light;

at least two optical receivers carried by the housing for receiving light emitted from the optical transmitter;

a light beam modifier carried by the housing and responsive to pressure changes thereon for modifying the light received by each of the at least two optical receivers; and

a processor operable for receiving an output signal from each of the optical receivers and providing a pressure measurement responsive to the light modifying,

wherein the processor sums an output signal from each of the at least two receivers and compares a resulting summed signal to a reference signal, and

wherein the summed signal is compared to a control signal delivered to the optical transmitter for modifying an output from the optical transmitter for maintaining the summed signal at a constant value, thus providing a linear conversion of the summed signal from the optical receivers to a pressure value representative of the pressure change.

13. A pressure sensor comprising:

a housing;

an optical transmitter carried by the housing, the optical transmitter operable for emitting light;

at least two optical receivers carried by the housing for receiving light emitted from the optical transmitter; and

a light beam modifier carried by the housing and responsive to pressure changes thereon for modifying the light received by each of the at least two optical receivers, the light beam modifier including a light reflective surface operable with an inside surface of the housing, wherein the light beam emitted from the optical transmitter is directed toward the light reflective surface for an angular reflection therefrom as a reflected light beam directed toward the at least two optical receivers, and wherein movement of the wall portion results in a change in the angular reflection of the light beam and the modifying of the light received by each of the at least two optical receivers; and

a processor carried by the housing for providing a pressure measurement responsive to the light modifying, the processor summing an output signal from each of the at least two receivers and comparing a resulting summed signal to a reference signal, wherein the summed signal is compared to a control signal delivered to the optical transmitter for modifying an output from the optical transmitter for maintaining the summed signal at a constant value, thus providing a linear conversion of the summed signal from the optical receivers to a pressure value representative of the pressure change.

14. A pressure sensor according to claim 13, wherein the wall portion movably responsive to the pressure change comprises a diaphragm.

15. A pressure sensor according to claim 13, further comprising a reflector carried on the inside surface, the reflector having the light reflective surface thereon.

16. A pressure sensor according to claim 13, further comprising a beam splitter positioned for receiving the reflected light beam and directing one portion to a first receiver of the at least two optical receivers and a second portion to a second receiver thereof.

18. A pressure sensor according to claim 17, A pressure sensor according to claim 16, further comprising a processor carried by the housing for providing a pressure measurement responsive to the light modifying, the processor summing an output signal from each of the at least two receivers and comparing a resulting summed signal to a reference signal, wherein the summed signal is compared to a control signal delivered to the optical transmitter for modifying an output from the optical transmitter for maintaining the summed signal at a constant value, thus providing a linear conversion of the summed signal from the optical receivers to a pressure value representative of the pressure change.

17. A pressure sensor comprising:

a housing;

an optical transmitter carried by the housing, the optical transmitter operable for emitting light;

at least two optical receivers carried by the housing for receiving light emitted from the optical transmitter; and

a light beam modifier carried by the housing and responsive to pressure changes thereon for modifying the light received by each of the at least two optical receivers, wherein the light beam modifier includes a barrier positioned in an optical path of the light beam, the barrier having a light transmitting portion therein for allowing a portion of the light emitted from the optical transmitter to be received by each of the at least two optical receivers, wherein the barrier is movably responsive to the pressure changes on the housing for movement of the light transmission portion, and thus an amount of light received by each of the at least two optical receivers.

19. A pressure sensor according to claim 17, wherein the light transmitting portion includes an aperture.

20. A pressure sensor according to claim 17, wherein the light transmitting portion comprises a transparent portion and at least one of a semitransparent portion and an opaque portion.

21. A pressure sensor according to claim 17, wherein the wall portion movably responsive to the pressure change comprises a diaphragm.

22. A pressure sensor according to claim 17, further comprising a beam splitter positioned for receiving the emitted light beam and directing one portion to a first receiver of the at least two optical receivers and a second portion to a second receiver thereof.