Non-contact level detector for fluids in a container

• US 20040093939A1
• Filed: 11/14/2002
• Published: 05/20/2004
• Est. Priority Date: 11/14/2002
• Status: Abandoned Application

• Current Assignee: Trinity Industries Incorporated
• Original Assignee: Trinity Industries Incorporated
• Inventors: Arias, Herman Diaz
• Application Number:
  US10/294,972
• Publication Number:
  US 20040093939A1
• Time in Patent Office: Days
• US Class Current: 73/290.00R
• CPC Class Codes: G01F 23/22 by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water involving the use of floats G01F23/30
• CPC Class Codes: G01F 23/292 Light , e.g. infrared or ultraviolet

Abstract

The present invention includes a level detector having a collimator being operable to block first electromagnetic radiation having a first range of orientations with respect to the level detector from passing through. The collimator is further operable to allow second electromagnetic radiation having a second range of orientations with respect to the level detector to pass through. The level detector includes a sensor that is positioned, with respect to the collimator, such that the sensor is operable to detect magnitudes of the second electromagnetic radiation. The sensor may be further operable to convert incident photon flux associated with the second electromagnetic radiation to electrical signals. In accordance with a particular embodiment of the present invention, the level detector includes an electronic unit that is operable to detect a radiation step in the second electromagnetic radiation, based upon changes in the magnitudes of the second electromagnetic radiation.

Claims

1. A level detector, comprising:

a collimator being operable to block first electromagnetic radiation having a first range of orientations with respect to the level detector from passing through, and being further operable to allow second electromagnetic radiation having a second range of orientations with respect to the level detector to pass through;

a sensor being positioned, with respect to the collimator, such that the sensor is operable to detect magnitudes of the second electromagnetic radiation; and

the sensor being operable to convert incident photon flux associated with the second electromagnetic radiation to electrical signals.

2. The level detector of claim 1, wherein the sensor comprises a thermal sensor.

3. The level detector of claim 1, wherein the sensor comprises a quantum sensor.

4. The level detector of claim 1, further comprising an electronic unit being operable to process the electrical signals.

5. The level detector of claim 4, wherein the electronic unit is further operable to detect a radiation step in the second electromagnetic radiation, based upon changes in the magnitudes of the second electromagnetic radiation.

6. The level detector of claim 5, further comprising a signal, wherein the signal is operable to actuate in response to detection of the radiation step.

7. The level detector of claim 6, wherein the signal comprises an audible signal.

8. The level detector of claim 6, wherein the signal comprises a visual signal.

9. The level detector of claim 8, wherein the signal comprises a light emitting diode being operable to project a light beam upon a surface of a container from which at least a portion of the second electromagnetic radiation is emanating, at approximately a location of the radiation step.

10. The level detector of claim 1, further comprising an amplifier being operable to amplify the electrical signals.

11. The level detector of claim 1, further comprising a voltage comparator being operable to compare voltages associated with the electrical signals.

12. The level detector of claim 4, further comprising a switch and a resistor, the switch and resistor providing an operator with the ability to adjust a sensitivity of the level detector.

13. The level detector of claim 4, wherein the electronic unit comprises a compensating circuit being operable to correct for warm-up noise generated by components of the level detector during a warm up period.

14. The level detector of claim 4, wherein the electronic unit comprises an analog to digital converter being operable to convert the electrical signals to corresponding digital signals.

15. The level detector of claim 14, further comprising a micro-controller being operable to receive the digital signals, and calculate a rate of change of the magnitudes of the second electromagnetic radiation.

16. The level detector of claim 1, wherein a window of the collimator is tapered along a horizontal cross section to at least partially correct for inadvertent horizontal movement by an operator of the level detector.

17. A method for detecting a level of fluid in a container, comprising:

scanning a surface of a container with a remote sensor, the container having a gas and a liquid within the container;

measuring radiation intensities along the surface of the container;

identifying a variation in radiation intensities adjacent an interface between the gas and the liquid.

18. The method of claim 17, wherein the sensor comprises a thermal sensor, and further comprising:

absorbing, at the thermal sensor, incident radiation flux from the container, the incident radiation flux being operable to increase a temperature of the sensor thereby changing a measurable physical property of the sensor.

19. The method of claim 18, wherein the measurable physical property comprises a voltage of the sensor.

20. The method of claim 18, wherein the measurable physical property comprises a resistance of the sensor.

21. The method of claim 17, wherein the sensor comprises a quantum sensor, and further comprising:

absorbing incident photons from the container;

exposing the photons to a semiconductor crystal;

the photons being operable to interact with a crystal lattice of the semiconductor crystal and generate free electrons or carriers; and

producing a signal voltage in the sensor.

22. The method of claim 17, further comprising compensating for a scanning speed of the sensor using high amplification and low noise electronics.

23. The method of claim 17, further comprising separating first signals originating outside the detector from second signals generated inside the sensor to compensate for warm-up of the sensor.

24. The method of claim 17, further comprising activating a sonic or visual signal when the interface is detected.

25. The method of claim 24, wherein the signal comprises a light emitting diode, and further comprising:

projecting a light spot on the surface of the container at approximately the location of the interface.

26. A method for detecting a level of fluid in a container, comprising:

receiving, at a collimator, first and second electromagnetic radiation, the first electromagnetic radiation having a first range of orientations with respect to the collimator, and the second electromagnetic radiation having a second range of orientations with respect to the collimator;

blocking the first electromagnetic radiation and allowing the second electromagnetic radiation to pass through the collimator;

detecting, at a sensor, magnitudes of the second electromagnetic radiation; and

converting incident photon flux associated with the second electromagnetic radiation to electrical signals.

27. The method of claim 26, further comprising correcting for warm-up noise generated by components of the level detector, using a compensated circuit.

28. The method of claim 27, further comprising amplifying the electrical signals.

29. The method of claim 28, further comprising converting the electrical signals to digital signals.

30. The method of claim 29, further comprising sampling the digital signals and calculating a rate of change.

31. The method of claim 30, further comprising identifying a step in the digital signals of a predetermined magnitude.